Experience

Publications

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Comparison of User Performance in Mixed 2D-3D Multi-Display Environments

  Interact 2013 (Springer IFIP )

  Stereoscopic displays and volumetric 3D displays capable of delivering 3D views have in use for many years. These standalone displays have been investigated in detail for their impact on users’ viewing experiences. Effects like aesthenopia and nausea are well-known for flat-screen based stereoscopic displays. However, these devices have not been tested in the context of multi-display environments (MDEs). The performance cost of repetitive switching between a 3D (stereo or volumetric) display and a standard 2D display are not known. In this paper, we perform a thorough user study where we investigate the effects of using such 3D displays within the context of a MDE. We report on our findings and discuss the implications of the same on designs involving such hybrid setups. Our experiments show that in the condition involving two 2D displays which allow for motion parallax and perspective correction, the participants performed the task the fastest.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Comparison of User Performance in Mixed 2D-3D Multi-Display Environments

  Interact 2013 (Springer IFIP )

  Stereoscopic displays and volumetric 3D displays capable of delivering 3D views have in use for many years. These standalone displays have been investigated in detail for their impact on users’ viewing experiences. Effects like aesthenopia and nausea are well-known for flat-screen based stereoscopic displays. However, these devices have not been tested in the context of multi-display environments (MDEs). The performance cost of repetitive switching between a 3D (stereo or volumetric) display and a standard 2D display are not known. In this paper, we perform a thorough user study where we investigate the effects of using such 3D displays within the context of a MDE. We report on our findings and discuss the implications of the same on designs involving such hybrid setups. Our experiments show that in the condition involving two 2D displays which allow for motion parallax and perspective correction, the participants performed the task the fastest.

• Portallax: Bringing 3D Displays Capabilities to Handhelds

  MobileHCI 2014 ACM

  We present Portallax, a clip-on technology to retrofit mobile devices with 3D display capabilities. Available technologies (e.g. Nintendo 3DS or LG Optimus) and clip-on solutions (e.g. 3DeeSlide and Grilli3D) force users to have a fixed head and device positions. This is contradictory to the nature of a mobile scenario, and limits the usage of interaction techniques such as tilting the device to control a game. Portallax uses an actuated parallax barrier and face tracking to realign the barrier's position to the user's position. This allows us to provide stereo, motion parallax and perspective correction cues in 60 degrees in front of the device. Our optimized design of the barrier minimizes colour distortion, maximizes resolution and produces bigger view-zones, which support ~81% of adults' interpupillary distances and allow eye tracking implemented with the front camera. We present a reference implementation, evaluate its key features and provide example applications illustrating the potential of Portallax.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Comparison of User Performance in Mixed 2D-3D Multi-Display Environments

  Interact 2013 (Springer IFIP )

  Stereoscopic displays and volumetric 3D displays capable of delivering 3D views have in use for many years. These standalone displays have been investigated in detail for their impact on users’ viewing experiences. Effects like aesthenopia and nausea are well-known for flat-screen based stereoscopic displays. However, these devices have not been tested in the context of multi-display environments (MDEs). The performance cost of repetitive switching between a 3D (stereo or volumetric) display and a standard 2D display are not known. In this paper, we perform a thorough user study where we investigate the effects of using such 3D displays within the context of a MDE. We report on our findings and discuss the implications of the same on designs involving such hybrid setups. Our experiments show that in the condition involving two 2D displays which allow for motion parallax and perspective correction, the participants performed the task the fastest.

• Portallax: Bringing 3D Displays Capabilities to Handhelds

  MobileHCI 2014 ACM

  We present Portallax, a clip-on technology to retrofit mobile devices with 3D display capabilities. Available technologies (e.g. Nintendo 3DS or LG Optimus) and clip-on solutions (e.g. 3DeeSlide and Grilli3D) force users to have a fixed head and device positions. This is contradictory to the nature of a mobile scenario, and limits the usage of interaction techniques such as tilting the device to control a game. Portallax uses an actuated parallax barrier and face tracking to realign the barrier's position to the user's position. This allows us to provide stereo, motion parallax and perspective correction cues in 60 degrees in front of the device. Our optimized design of the barrier minimizes colour distortion, maximizes resolution and produces bigger view-zones, which support ~81% of adults' interpupillary distances and allow eye tracking implemented with the front camera. We present a reference implementation, evaluate its key features and provide example applications illustrating the potential of Portallax.

• Spending Time with Money: from shared values to social connectivity

  ACM

  There is a rapidly growing momentum driving the development of mobile payment systems for co-present interactions, using near-field communication on smartphones and contactless payment systems. The design (and marketing) imperative for this is to enable faster, simpler, effortless and secure transactions, yet our evidence shows that this focus on reducing transactional friction may ignore other important features around making payments. We draw from empirical data to consider user interactions around financial exchanges made on mobile phones. Our findings examine how the practices around making payments support people in making connections, to other people, to their communities, to the places they move through, to their environment, and to what they consume. While these social and community bonds shape the kinds of interactions that become possible, they also shape how users feel about, and act on, the values that they hold with their co-users. We draw implications for future payment systems that make use of community connections, build trust, leverage transactional latency, and generate opportunities for rich social interactions.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Comparison of User Performance in Mixed 2D-3D Multi-Display Environments

  Interact 2013 (Springer IFIP )

  Stereoscopic displays and volumetric 3D displays capable of delivering 3D views have in use for many years. These standalone displays have been investigated in detail for their impact on users’ viewing experiences. Effects like aesthenopia and nausea are well-known for flat-screen based stereoscopic displays. However, these devices have not been tested in the context of multi-display environments (MDEs). The performance cost of repetitive switching between a 3D (stereo or volumetric) display and a standard 2D display are not known. In this paper, we perform a thorough user study where we investigate the effects of using such 3D displays within the context of a MDE. We report on our findings and discuss the implications of the same on designs involving such hybrid setups. Our experiments show that in the condition involving two 2D displays which allow for motion parallax and perspective correction, the participants performed the task the fastest.

• Portallax: Bringing 3D Displays Capabilities to Handhelds

  MobileHCI 2014 ACM

  We present Portallax, a clip-on technology to retrofit mobile devices with 3D display capabilities. Available technologies (e.g. Nintendo 3DS or LG Optimus) and clip-on solutions (e.g. 3DeeSlide and Grilli3D) force users to have a fixed head and device positions. This is contradictory to the nature of a mobile scenario, and limits the usage of interaction techniques such as tilting the device to control a game. Portallax uses an actuated parallax barrier and face tracking to realign the barrier's position to the user's position. This allows us to provide stereo, motion parallax and perspective correction cues in 60 degrees in front of the device. Our optimized design of the barrier minimizes colour distortion, maximizes resolution and produces bigger view-zones, which support ~81% of adults' interpupillary distances and allow eye tracking implemented with the front camera. We present a reference implementation, evaluate its key features and provide example applications illustrating the potential of Portallax.

• Spending Time with Money: from shared values to social connectivity

  ACM

  There is a rapidly growing momentum driving the development of mobile payment systems for co-present interactions, using near-field communication on smartphones and contactless payment systems. The design (and marketing) imperative for this is to enable faster, simpler, effortless and secure transactions, yet our evidence shows that this focus on reducing transactional friction may ignore other important features around making payments. We draw from empirical data to consider user interactions around financial exchanges made on mobile phones. Our findings examine how the practices around making payments support people in making connections, to other people, to their communities, to the places they move through, to their environment, and to what they consume. While these social and community bonds shape the kinds of interactions that become possible, they also shape how users feel about, and act on, the values that they hold with their co-users. We draw implications for future payment systems that make use of community connections, build trust, leverage transactional latency, and generate opportunities for rich social interactions.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Comparison of User Performance in Mixed 2D-3D Multi-Display Environments

  Interact 2013 (Springer IFIP )

  Stereoscopic displays and volumetric 3D displays capable of delivering 3D views have in use for many years. These standalone displays have been investigated in detail for their impact on users’ viewing experiences. Effects like aesthenopia and nausea are well-known for flat-screen based stereoscopic displays. However, these devices have not been tested in the context of multi-display environments (MDEs). The performance cost of repetitive switching between a 3D (stereo or volumetric) display and a standard 2D display are not known. In this paper, we perform a thorough user study where we investigate the effects of using such 3D displays within the context of a MDE. We report on our findings and discuss the implications of the same on designs involving such hybrid setups. Our experiments show that in the condition involving two 2D displays which allow for motion parallax and perspective correction, the participants performed the task the fastest.

• Portallax: Bringing 3D Displays Capabilities to Handhelds

  MobileHCI 2014 ACM

  We present Portallax, a clip-on technology to retrofit mobile devices with 3D display capabilities. Available technologies (e.g. Nintendo 3DS or LG Optimus) and clip-on solutions (e.g. 3DeeSlide and Grilli3D) force users to have a fixed head and device positions. This is contradictory to the nature of a mobile scenario, and limits the usage of interaction techniques such as tilting the device to control a game. Portallax uses an actuated parallax barrier and face tracking to realign the barrier's position to the user's position. This allows us to provide stereo, motion parallax and perspective correction cues in 60 degrees in front of the device. Our optimized design of the barrier minimizes colour distortion, maximizes resolution and produces bigger view-zones, which support ~81% of adults' interpupillary distances and allow eye tracking implemented with the front camera. We present a reference implementation, evaluate its key features and provide example applications illustrating the potential of Portallax.

• Spending Time with Money: from shared values to social connectivity

  ACM

  There is a rapidly growing momentum driving the development of mobile payment systems for co-present interactions, using near-field communication on smartphones and contactless payment systems. The design (and marketing) imperative for this is to enable faster, simpler, effortless and secure transactions, yet our evidence shows that this focus on reducing transactional friction may ignore other important features around making payments. We draw from empirical data to consider user interactions around financial exchanges made on mobile phones. Our findings examine how the practices around making payments support people in making connections, to other people, to their communities, to the places they move through, to their environment, and to what they consume. While these social and community bonds shape the kinds of interactions that become possible, they also shape how users feel about, and act on, the values that they hold with their co-users. We draw implications for future payment systems that make use of community connections, build trust, leverage transactional latency, and generate opportunities for rich social interactions.

• PiVOT : Personalized View-Overlays for Tabletops

  25th Annual ACM Symposium on User Interface Software and Technology

  PiVOT is a tabletop system aimed at supporting mixed-focus collaborative tasks. Through two view-zones, PiVOT provides personalized views to individual users while presenting an unaffected and unobstructed shared view to all users. The system supports multiple personalized views which can be present at the same spatial location and yet be only visible to the users it belongs to. PiVOT also allows the creation of personal views that can be either 2D or (auto-stereoscopic) 3D images. [to appear in UIST 2012 http://www.acm.org/uist/uist2012/] PiVOT is a result of exploration of different designs meant to address the seemingly opposing challenges of shared and personalized views.A sample prototype has been implemented and evaluated to validate our design ideas and can run a set of sample applications that demonstrate the utility of the system.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Comparison of User Performance in Mixed 2D-3D Multi-Display Environments

  Interact 2013 (Springer IFIP )

  Stereoscopic displays and volumetric 3D displays capable of delivering 3D views have in use for many years. These standalone displays have been investigated in detail for their impact on users’ viewing experiences. Effects like aesthenopia and nausea are well-known for flat-screen based stereoscopic displays. However, these devices have not been tested in the context of multi-display environments (MDEs). The performance cost of repetitive switching between a 3D (stereo or volumetric) display and a standard 2D display are not known. In this paper, we perform a thorough user study where we investigate the effects of using such 3D displays within the context of a MDE. We report on our findings and discuss the implications of the same on designs involving such hybrid setups. Our experiments show that in the condition involving two 2D displays which allow for motion parallax and perspective correction, the participants performed the task the fastest.

• Portallax: Bringing 3D Displays Capabilities to Handhelds

  MobileHCI 2014 ACM

  We present Portallax, a clip-on technology to retrofit mobile devices with 3D display capabilities. Available technologies (e.g. Nintendo 3DS or LG Optimus) and clip-on solutions (e.g. 3DeeSlide and Grilli3D) force users to have a fixed head and device positions. This is contradictory to the nature of a mobile scenario, and limits the usage of interaction techniques such as tilting the device to control a game. Portallax uses an actuated parallax barrier and face tracking to realign the barrier's position to the user's position. This allows us to provide stereo, motion parallax and perspective correction cues in 60 degrees in front of the device. Our optimized design of the barrier minimizes colour distortion, maximizes resolution and produces bigger view-zones, which support ~81% of adults' interpupillary distances and allow eye tracking implemented with the front camera. We present a reference implementation, evaluate its key features and provide example applications illustrating the potential of Portallax.

• Spending Time with Money: from shared values to social connectivity

  ACM

  There is a rapidly growing momentum driving the development of mobile payment systems for co-present interactions, using near-field communication on smartphones and contactless payment systems. The design (and marketing) imperative for this is to enable faster, simpler, effortless and secure transactions, yet our evidence shows that this focus on reducing transactional friction may ignore other important features around making payments. We draw from empirical data to consider user interactions around financial exchanges made on mobile phones. Our findings examine how the practices around making payments support people in making connections, to other people, to their communities, to the places they move through, to their environment, and to what they consume. While these social and community bonds shape the kinds of interactions that become possible, they also shape how users feel about, and act on, the values that they hold with their co-users. We draw implications for future payment systems that make use of community connections, build trust, leverage transactional latency, and generate opportunities for rich social interactions.

• PiVOT : Personalized View-Overlays for Tabletops

  25th Annual ACM Symposium on User Interface Software and Technology

  PiVOT is a tabletop system aimed at supporting mixed-focus collaborative tasks. Through two view-zones, PiVOT provides personalized views to individual users while presenting an unaffected and unobstructed shared view to all users. The system supports multiple personalized views which can be present at the same spatial location and yet be only visible to the users it belongs to. PiVOT also allows the creation of personal views that can be either 2D or (auto-stereoscopic) 3D images. [to appear in UIST 2012 http://www.acm.org/uist/uist2012/] PiVOT is a result of exploration of different designs meant to address the seemingly opposing challenges of shared and personalized views.A sample prototype has been implemented and evaluated to validate our design ideas and can run a set of sample applications that demonstrate the utility of the system.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Comparison of User Performance in Mixed 2D-3D Multi-Display Environments

  Interact 2013 (Springer IFIP )

  Stereoscopic displays and volumetric 3D displays capable of delivering 3D views have in use for many years. These standalone displays have been investigated in detail for their impact on users’ viewing experiences. Effects like aesthenopia and nausea are well-known for flat-screen based stereoscopic displays. However, these devices have not been tested in the context of multi-display environments (MDEs). The performance cost of repetitive switching between a 3D (stereo or volumetric) display and a standard 2D display are not known. In this paper, we perform a thorough user study where we investigate the effects of using such 3D displays within the context of a MDE. We report on our findings and discuss the implications of the same on designs involving such hybrid setups. Our experiments show that in the condition involving two 2D displays which allow for motion parallax and perspective correction, the participants performed the task the fastest.

• Portallax: Bringing 3D Displays Capabilities to Handhelds

  MobileHCI 2014 ACM

  We present Portallax, a clip-on technology to retrofit mobile devices with 3D display capabilities. Available technologies (e.g. Nintendo 3DS or LG Optimus) and clip-on solutions (e.g. 3DeeSlide and Grilli3D) force users to have a fixed head and device positions. This is contradictory to the nature of a mobile scenario, and limits the usage of interaction techniques such as tilting the device to control a game. Portallax uses an actuated parallax barrier and face tracking to realign the barrier's position to the user's position. This allows us to provide stereo, motion parallax and perspective correction cues in 60 degrees in front of the device. Our optimized design of the barrier minimizes colour distortion, maximizes resolution and produces bigger view-zones, which support ~81% of adults' interpupillary distances and allow eye tracking implemented with the front camera. We present a reference implementation, evaluate its key features and provide example applications illustrating the potential of Portallax.

• Spending Time with Money: from shared values to social connectivity

  ACM

  There is a rapidly growing momentum driving the development of mobile payment systems for co-present interactions, using near-field communication on smartphones and contactless payment systems. The design (and marketing) imperative for this is to enable faster, simpler, effortless and secure transactions, yet our evidence shows that this focus on reducing transactional friction may ignore other important features around making payments. We draw from empirical data to consider user interactions around financial exchanges made on mobile phones. Our findings examine how the practices around making payments support people in making connections, to other people, to their communities, to the places they move through, to their environment, and to what they consume. While these social and community bonds shape the kinds of interactions that become possible, they also shape how users feel about, and act on, the values that they hold with their co-users. We draw implications for future payment systems that make use of community connections, build trust, leverage transactional latency, and generate opportunities for rich social interactions.

• PiVOT : Personalized View-Overlays for Tabletops

  25th Annual ACM Symposium on User Interface Software and Technology

  PiVOT is a tabletop system aimed at supporting mixed-focus collaborative tasks. Through two view-zones, PiVOT provides personalized views to individual users while presenting an unaffected and unobstructed shared view to all users. The system supports multiple personalized views which can be present at the same spatial location and yet be only visible to the users it belongs to. PiVOT also allows the creation of personal views that can be either 2D or (auto-stereoscopic) 3D images. [to appear in UIST 2012 http://www.acm.org/uist/uist2012/] PiVOT is a result of exploration of different designs meant to address the seemingly opposing challenges of shared and personalized views.A sample prototype has been implemented and evaluated to validate our design ideas and can run a set of sample applications that demonstrate the utility of the system.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Temporal, Affective, and Embodied Characteristics of Taste Experiences: A Framework for Design

  CHI '14 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Comparison of User Performance in Mixed 2D-3D Multi-Display Environments

  Interact 2013 (Springer IFIP )

  Stereoscopic displays and volumetric 3D displays capable of delivering 3D views have in use for many years. These standalone displays have been investigated in detail for their impact on users’ viewing experiences. Effects like aesthenopia and nausea are well-known for flat-screen based stereoscopic displays. However, these devices have not been tested in the context of multi-display environments (MDEs). The performance cost of repetitive switching between a 3D (stereo or volumetric) display and a standard 2D display are not known. In this paper, we perform a thorough user study where we investigate the effects of using such 3D displays within the context of a MDE. We report on our findings and discuss the implications of the same on designs involving such hybrid setups. Our experiments show that in the condition involving two 2D displays which allow for motion parallax and perspective correction, the participants performed the task the fastest.

• Portallax: Bringing 3D Displays Capabilities to Handhelds

  MobileHCI 2014 ACM

  We present Portallax, a clip-on technology to retrofit mobile devices with 3D display capabilities. Available technologies (e.g. Nintendo 3DS or LG Optimus) and clip-on solutions (e.g. 3DeeSlide and Grilli3D) force users to have a fixed head and device positions. This is contradictory to the nature of a mobile scenario, and limits the usage of interaction techniques such as tilting the device to control a game. Portallax uses an actuated parallax barrier and face tracking to realign the barrier's position to the user's position. This allows us to provide stereo, motion parallax and perspective correction cues in 60 degrees in front of the device. Our optimized design of the barrier minimizes colour distortion, maximizes resolution and produces bigger view-zones, which support ~81% of adults' interpupillary distances and allow eye tracking implemented with the front camera. We present a reference implementation, evaluate its key features and provide example applications illustrating the potential of Portallax.

• Spending Time with Money: from shared values to social connectivity

  ACM

  There is a rapidly growing momentum driving the development of mobile payment systems for co-present interactions, using near-field communication on smartphones and contactless payment systems. The design (and marketing) imperative for this is to enable faster, simpler, effortless and secure transactions, yet our evidence shows that this focus on reducing transactional friction may ignore other important features around making payments. We draw from empirical data to consider user interactions around financial exchanges made on mobile phones. Our findings examine how the practices around making payments support people in making connections, to other people, to their communities, to the places they move through, to their environment, and to what they consume. While these social and community bonds shape the kinds of interactions that become possible, they also shape how users feel about, and act on, the values that they hold with their co-users. We draw implications for future payment systems that make use of community connections, build trust, leverage transactional latency, and generate opportunities for rich social interactions.

• PiVOT : Personalized View-Overlays for Tabletops

  25th Annual ACM Symposium on User Interface Software and Technology

  PiVOT is a tabletop system aimed at supporting mixed-focus collaborative tasks. Through two view-zones, PiVOT provides personalized views to individual users while presenting an unaffected and unobstructed shared view to all users. The system supports multiple personalized views which can be present at the same spatial location and yet be only visible to the users it belongs to. PiVOT also allows the creation of personal views that can be either 2D or (auto-stereoscopic) 3D images. [to appear in UIST 2012 http://www.acm.org/uist/uist2012/] PiVOT is a result of exploration of different designs meant to address the seemingly opposing challenges of shared and personalized views.A sample prototype has been implemented and evaluated to validate our design ideas and can run a set of sample applications that demonstrate the utility of the system.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Temporal, Affective, and Embodied Characteristics of Taste Experiences: A Framework for Design

  CHI '14 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

• D-FLIP: Dynamic & Flexible Interactive PhotoShow

  In proceedings of Advances in Computer Entertainment (ACE 2013)

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Comparison of User Performance in Mixed 2D-3D Multi-Display Environments

  Interact 2013 (Springer IFIP )

  Stereoscopic displays and volumetric 3D displays capable of delivering 3D views have in use for many years. These standalone displays have been investigated in detail for their impact on users’ viewing experiences. Effects like aesthenopia and nausea are well-known for flat-screen based stereoscopic displays. However, these devices have not been tested in the context of multi-display environments (MDEs). The performance cost of repetitive switching between a 3D (stereo or volumetric) display and a standard 2D display are not known. In this paper, we perform a thorough user study where we investigate the effects of using such 3D displays within the context of a MDE. We report on our findings and discuss the implications of the same on designs involving such hybrid setups. Our experiments show that in the condition involving two 2D displays which allow for motion parallax and perspective correction, the participants performed the task the fastest.

• Portallax: Bringing 3D Displays Capabilities to Handhelds

  MobileHCI 2014 ACM

  We present Portallax, a clip-on technology to retrofit mobile devices with 3D display capabilities. Available technologies (e.g. Nintendo 3DS or LG Optimus) and clip-on solutions (e.g. 3DeeSlide and Grilli3D) force users to have a fixed head and device positions. This is contradictory to the nature of a mobile scenario, and limits the usage of interaction techniques such as tilting the device to control a game. Portallax uses an actuated parallax barrier and face tracking to realign the barrier's position to the user's position. This allows us to provide stereo, motion parallax and perspective correction cues in 60 degrees in front of the device. Our optimized design of the barrier minimizes colour distortion, maximizes resolution and produces bigger view-zones, which support ~81% of adults' interpupillary distances and allow eye tracking implemented with the front camera. We present a reference implementation, evaluate its key features and provide example applications illustrating the potential of Portallax.

• Spending Time with Money: from shared values to social connectivity

  ACM

  There is a rapidly growing momentum driving the development of mobile payment systems for co-present interactions, using near-field communication on smartphones and contactless payment systems. The design (and marketing) imperative for this is to enable faster, simpler, effortless and secure transactions, yet our evidence shows that this focus on reducing transactional friction may ignore other important features around making payments. We draw from empirical data to consider user interactions around financial exchanges made on mobile phones. Our findings examine how the practices around making payments support people in making connections, to other people, to their communities, to the places they move through, to their environment, and to what they consume. While these social and community bonds shape the kinds of interactions that become possible, they also shape how users feel about, and act on, the values that they hold with their co-users. We draw implications for future payment systems that make use of community connections, build trust, leverage transactional latency, and generate opportunities for rich social interactions.

• PiVOT : Personalized View-Overlays for Tabletops

  25th Annual ACM Symposium on User Interface Software and Technology

  PiVOT is a tabletop system aimed at supporting mixed-focus collaborative tasks. Through two view-zones, PiVOT provides personalized views to individual users while presenting an unaffected and unobstructed shared view to all users. The system supports multiple personalized views which can be present at the same spatial location and yet be only visible to the users it belongs to. PiVOT also allows the creation of personal views that can be either 2D or (auto-stereoscopic) 3D images. [to appear in UIST 2012 http://www.acm.org/uist/uist2012/] PiVOT is a result of exploration of different designs meant to address the seemingly opposing challenges of shared and personalized views.A sample prototype has been implemented and evaluated to validate our design ideas and can run a set of sample applications that demonstrate the utility of the system.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Temporal, Affective, and Embodied Characteristics of Taste Experiences: A Framework for Design

  CHI '14 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

• D-FLIP: Dynamic & Flexible Interactive PhotoShow

  In proceedings of Advances in Computer Entertainment (ACE 2013)

• Online Single Trial Ern Detection As An Interaction Aid In HCI Applications

  CHI 2011 Workshop on Brain and Body Interfaces: Designing for Meaningful Interaction

  Error-related negativity (ERN) is a form of an Event Related Potential signal which can be triggered in the brain when a user either makes a mistake or the application behaves differently from the expectation of the user. The first step to harness the benefits of ERN in HCI applications is to detect the patterns in real-time on a single trial basis. In this paper we present our initial results in detecting ERN. Using a logistic regression technique, we have achieved a 70% recognition rate of erroneous and correct single trials. We then explored several designs, e.g. using ERN to help a user in the moment of bad decision in a map navigation task. Through multiple designs and careful user testing, we aim to identify guidelines and design principles that can help HCI researchers to include ERN as an interaction aid in their applications.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Comparison of User Performance in Mixed 2D-3D Multi-Display Environments

  Interact 2013 (Springer IFIP )

  Stereoscopic displays and volumetric 3D displays capable of delivering 3D views have in use for many years. These standalone displays have been investigated in detail for their impact on users’ viewing experiences. Effects like aesthenopia and nausea are well-known for flat-screen based stereoscopic displays. However, these devices have not been tested in the context of multi-display environments (MDEs). The performance cost of repetitive switching between a 3D (stereo or volumetric) display and a standard 2D display are not known. In this paper, we perform a thorough user study where we investigate the effects of using such 3D displays within the context of a MDE. We report on our findings and discuss the implications of the same on designs involving such hybrid setups. Our experiments show that in the condition involving two 2D displays which allow for motion parallax and perspective correction, the participants performed the task the fastest.

• Portallax: Bringing 3D Displays Capabilities to Handhelds

  MobileHCI 2014 ACM

  We present Portallax, a clip-on technology to retrofit mobile devices with 3D display capabilities. Available technologies (e.g. Nintendo 3DS or LG Optimus) and clip-on solutions (e.g. 3DeeSlide and Grilli3D) force users to have a fixed head and device positions. This is contradictory to the nature of a mobile scenario, and limits the usage of interaction techniques such as tilting the device to control a game. Portallax uses an actuated parallax barrier and face tracking to realign the barrier's position to the user's position. This allows us to provide stereo, motion parallax and perspective correction cues in 60 degrees in front of the device. Our optimized design of the barrier minimizes colour distortion, maximizes resolution and produces bigger view-zones, which support ~81% of adults' interpupillary distances and allow eye tracking implemented with the front camera. We present a reference implementation, evaluate its key features and provide example applications illustrating the potential of Portallax.

• Spending Time with Money: from shared values to social connectivity

  ACM

  There is a rapidly growing momentum driving the development of mobile payment systems for co-present interactions, using near-field communication on smartphones and contactless payment systems. The design (and marketing) imperative for this is to enable faster, simpler, effortless and secure transactions, yet our evidence shows that this focus on reducing transactional friction may ignore other important features around making payments. We draw from empirical data to consider user interactions around financial exchanges made on mobile phones. Our findings examine how the practices around making payments support people in making connections, to other people, to their communities, to the places they move through, to their environment, and to what they consume. While these social and community bonds shape the kinds of interactions that become possible, they also shape how users feel about, and act on, the values that they hold with their co-users. We draw implications for future payment systems that make use of community connections, build trust, leverage transactional latency, and generate opportunities for rich social interactions.

• PiVOT : Personalized View-Overlays for Tabletops

  25th Annual ACM Symposium on User Interface Software and Technology

  PiVOT is a tabletop system aimed at supporting mixed-focus collaborative tasks. Through two view-zones, PiVOT provides personalized views to individual users while presenting an unaffected and unobstructed shared view to all users. The system supports multiple personalized views which can be present at the same spatial location and yet be only visible to the users it belongs to. PiVOT also allows the creation of personal views that can be either 2D or (auto-stereoscopic) 3D images. [to appear in UIST 2012 http://www.acm.org/uist/uist2012/] PiVOT is a result of exploration of different designs meant to address the seemingly opposing challenges of shared and personalized views.A sample prototype has been implemented and evaluated to validate our design ideas and can run a set of sample applications that demonstrate the utility of the system.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Temporal, Affective, and Embodied Characteristics of Taste Experiences: A Framework for Design

  CHI '14 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

• D-FLIP: Dynamic & Flexible Interactive PhotoShow

  In proceedings of Advances in Computer Entertainment (ACE 2013)

• Online Single Trial Ern Detection As An Interaction Aid In HCI Applications

  CHI 2011 Workshop on Brain and Body Interfaces: Designing for Meaningful Interaction

  Error-related negativity (ERN) is a form of an Event Related Potential signal which can be triggered in the brain when a user either makes a mistake or the application behaves differently from the expectation of the user. The first step to harness the benefits of ERN in HCI applications is to detect the patterns in real-time on a single trial basis. In this paper we present our initial results in detecting ERN. Using a logistic regression technique, we have achieved a 70% recognition rate of erroneous and correct single trials. We then explored several designs, e.g. using ERN to help a user in the moment of bad decision in a map navigation task. Through multiple designs and careful user testing, we aim to identify guidelines and design principles that can help HCI researchers to include ERN as an interaction aid in their applications.

• Modeling steering within above-the-surface interaction layers

  CHI '07 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

  A Mathematical Model for Steering above Tabletops.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Comparison of User Performance in Mixed 2D-3D Multi-Display Environments

  Interact 2013 (Springer IFIP )

  Stereoscopic displays and volumetric 3D displays capable of delivering 3D views have in use for many years. These standalone displays have been investigated in detail for their impact on users’ viewing experiences. Effects like aesthenopia and nausea are well-known for flat-screen based stereoscopic displays. However, these devices have not been tested in the context of multi-display environments (MDEs). The performance cost of repetitive switching between a 3D (stereo or volumetric) display and a standard 2D display are not known. In this paper, we perform a thorough user study where we investigate the effects of using such 3D displays within the context of a MDE. We report on our findings and discuss the implications of the same on designs involving such hybrid setups. Our experiments show that in the condition involving two 2D displays which allow for motion parallax and perspective correction, the participants performed the task the fastest.

• Portallax: Bringing 3D Displays Capabilities to Handhelds

  MobileHCI 2014 ACM

  We present Portallax, a clip-on technology to retrofit mobile devices with 3D display capabilities. Available technologies (e.g. Nintendo 3DS or LG Optimus) and clip-on solutions (e.g. 3DeeSlide and Grilli3D) force users to have a fixed head and device positions. This is contradictory to the nature of a mobile scenario, and limits the usage of interaction techniques such as tilting the device to control a game. Portallax uses an actuated parallax barrier and face tracking to realign the barrier's position to the user's position. This allows us to provide stereo, motion parallax and perspective correction cues in 60 degrees in front of the device. Our optimized design of the barrier minimizes colour distortion, maximizes resolution and produces bigger view-zones, which support ~81% of adults' interpupillary distances and allow eye tracking implemented with the front camera. We present a reference implementation, evaluate its key features and provide example applications illustrating the potential of Portallax.

• Spending Time with Money: from shared values to social connectivity

  ACM

  There is a rapidly growing momentum driving the development of mobile payment systems for co-present interactions, using near-field communication on smartphones and contactless payment systems. The design (and marketing) imperative for this is to enable faster, simpler, effortless and secure transactions, yet our evidence shows that this focus on reducing transactional friction may ignore other important features around making payments. We draw from empirical data to consider user interactions around financial exchanges made on mobile phones. Our findings examine how the practices around making payments support people in making connections, to other people, to their communities, to the places they move through, to their environment, and to what they consume. While these social and community bonds shape the kinds of interactions that become possible, they also shape how users feel about, and act on, the values that they hold with their co-users. We draw implications for future payment systems that make use of community connections, build trust, leverage transactional latency, and generate opportunities for rich social interactions.

• PiVOT : Personalized View-Overlays for Tabletops

  25th Annual ACM Symposium on User Interface Software and Technology

  PiVOT is a tabletop system aimed at supporting mixed-focus collaborative tasks. Through two view-zones, PiVOT provides personalized views to individual users while presenting an unaffected and unobstructed shared view to all users. The system supports multiple personalized views which can be present at the same spatial location and yet be only visible to the users it belongs to. PiVOT also allows the creation of personal views that can be either 2D or (auto-stereoscopic) 3D images. [to appear in UIST 2012 http://www.acm.org/uist/uist2012/] PiVOT is a result of exploration of different designs meant to address the seemingly opposing challenges of shared and personalized views.A sample prototype has been implemented and evaluated to validate our design ideas and can run a set of sample applications that demonstrate the utility of the system.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Temporal, Affective, and Embodied Characteristics of Taste Experiences: A Framework for Design

  CHI '14 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

• D-FLIP: Dynamic & Flexible Interactive PhotoShow

  In proceedings of Advances in Computer Entertainment (ACE 2013)

• Online Single Trial Ern Detection As An Interaction Aid In HCI Applications

  CHI 2011 Workshop on Brain and Body Interfaces: Designing for Meaningful Interaction

  Error-related negativity (ERN) is a form of an Event Related Potential signal which can be triggered in the brain when a user either makes a mistake or the application behaves differently from the expectation of the user. The first step to harness the benefits of ERN in HCI applications is to detect the patterns in real-time on a single trial basis. In this paper we present our initial results in detecting ERN. Using a logistic regression technique, we have achieved a 70% recognition rate of erroneous and correct single trials. We then explored several designs, e.g. using ERN to help a user in the moment of bad decision in a map navigation task. Through multiple designs and careful user testing, we aim to identify guidelines and design principles that can help HCI researchers to include ERN as an interaction aid in their applications.

• Modeling steering within above-the-surface interaction layers

  CHI '07 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

  A Mathematical Model for Steering above Tabletops.

• Ultrahaptics: multi-point mid-air haptic feedback for touch surfaces

  Proceedings of the 26th annual ACM symposium on User Interface Software and Technology

  We introduce UltraHaptics, a system designed to provide multi-point haptic feedback above an interactive surface. UltraHaptics employs focused ultrasound to project discrete points of haptic feedback through the display and directly on to users' unadorned hands. We investigate the desirable properties of an acoustically transparent display and demonstrate that the system is capable of creating multiple localised points of feedback in mid-air. Through psychophysical experiments we show that feedback points with different tactile properties can be identified at smaller separations. We also show that users are able to distinguish between different vibration frequencies of non-contact points with training. Finally, we explore a number of exciting new interaction possibilities that UltraHaptics provides.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Comparison of User Performance in Mixed 2D-3D Multi-Display Environments

  Interact 2013 (Springer IFIP )

  Stereoscopic displays and volumetric 3D displays capable of delivering 3D views have in use for many years. These standalone displays have been investigated in detail for their impact on users’ viewing experiences. Effects like aesthenopia and nausea are well-known for flat-screen based stereoscopic displays. However, these devices have not been tested in the context of multi-display environments (MDEs). The performance cost of repetitive switching between a 3D (stereo or volumetric) display and a standard 2D display are not known. In this paper, we perform a thorough user study where we investigate the effects of using such 3D displays within the context of a MDE. We report on our findings and discuss the implications of the same on designs involving such hybrid setups. Our experiments show that in the condition involving two 2D displays which allow for motion parallax and perspective correction, the participants performed the task the fastest.

• Portallax: Bringing 3D Displays Capabilities to Handhelds

  MobileHCI 2014 ACM

  We present Portallax, a clip-on technology to retrofit mobile devices with 3D display capabilities. Available technologies (e.g. Nintendo 3DS or LG Optimus) and clip-on solutions (e.g. 3DeeSlide and Grilli3D) force users to have a fixed head and device positions. This is contradictory to the nature of a mobile scenario, and limits the usage of interaction techniques such as tilting the device to control a game. Portallax uses an actuated parallax barrier and face tracking to realign the barrier's position to the user's position. This allows us to provide stereo, motion parallax and perspective correction cues in 60 degrees in front of the device. Our optimized design of the barrier minimizes colour distortion, maximizes resolution and produces bigger view-zones, which support ~81% of adults' interpupillary distances and allow eye tracking implemented with the front camera. We present a reference implementation, evaluate its key features and provide example applications illustrating the potential of Portallax.

• Spending Time with Money: from shared values to social connectivity

  ACM

  There is a rapidly growing momentum driving the development of mobile payment systems for co-present interactions, using near-field communication on smartphones and contactless payment systems. The design (and marketing) imperative for this is to enable faster, simpler, effortless and secure transactions, yet our evidence shows that this focus on reducing transactional friction may ignore other important features around making payments. We draw from empirical data to consider user interactions around financial exchanges made on mobile phones. Our findings examine how the practices around making payments support people in making connections, to other people, to their communities, to the places they move through, to their environment, and to what they consume. While these social and community bonds shape the kinds of interactions that become possible, they also shape how users feel about, and act on, the values that they hold with their co-users. We draw implications for future payment systems that make use of community connections, build trust, leverage transactional latency, and generate opportunities for rich social interactions.

• PiVOT : Personalized View-Overlays for Tabletops

  25th Annual ACM Symposium on User Interface Software and Technology

  PiVOT is a tabletop system aimed at supporting mixed-focus collaborative tasks. Through two view-zones, PiVOT provides personalized views to individual users while presenting an unaffected and unobstructed shared view to all users. The system supports multiple personalized views which can be present at the same spatial location and yet be only visible to the users it belongs to. PiVOT also allows the creation of personal views that can be either 2D or (auto-stereoscopic) 3D images. [to appear in UIST 2012 http://www.acm.org/uist/uist2012/] PiVOT is a result of exploration of different designs meant to address the seemingly opposing challenges of shared and personalized views.A sample prototype has been implemented and evaluated to validate our design ideas and can run a set of sample applications that demonstrate the utility of the system.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Temporal, Affective, and Embodied Characteristics of Taste Experiences: A Framework for Design

  CHI '14 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

• D-FLIP: Dynamic & Flexible Interactive PhotoShow

  In proceedings of Advances in Computer Entertainment (ACE 2013)

• Online Single Trial Ern Detection As An Interaction Aid In HCI Applications

  CHI 2011 Workshop on Brain and Body Interfaces: Designing for Meaningful Interaction

  Error-related negativity (ERN) is a form of an Event Related Potential signal which can be triggered in the brain when a user either makes a mistake or the application behaves differently from the expectation of the user. The first step to harness the benefits of ERN in HCI applications is to detect the patterns in real-time on a single trial basis. In this paper we present our initial results in detecting ERN. Using a logistic regression technique, we have achieved a 70% recognition rate of erroneous and correct single trials. We then explored several designs, e.g. using ERN to help a user in the moment of bad decision in a map navigation task. Through multiple designs and careful user testing, we aim to identify guidelines and design principles that can help HCI researchers to include ERN as an interaction aid in their applications.

• Modeling steering within above-the-surface interaction layers

  CHI '07 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

  A Mathematical Model for Steering above Tabletops.

• Ultrahaptics: multi-point mid-air haptic feedback for touch surfaces

  Proceedings of the 26th annual ACM symposium on User Interface Software and Technology

  We introduce UltraHaptics, a system designed to provide multi-point haptic feedback above an interactive surface. UltraHaptics employs focused ultrasound to project discrete points of haptic feedback through the display and directly on to users' unadorned hands. We investigate the desirable properties of an acoustically transparent display and demonstrate that the system is capable of creating multiple localised points of feedback in mid-air. Through psychophysical experiments we show that feedback points with different tactile properties can be identified at smaller separations. We also show that users are able to distinguish between different vibration frequencies of non-contact points with training. Finally, we explore a number of exciting new interaction possibilities that UltraHaptics provides.

• Group Interaction on Interactive Multi-touch Tables by Children in India

  Proceedings of the 11th International Conference on Interaction Design and Children

  Interactive tables provide multi-touch capabilities that can enable children to collaborate face-to-face simultaneously. In this paper we extend existing understanding of children's use of interactive tabletops by examining their use by school children in a school in Delhi, India. In the study, we explore how the school children exhibit particular types of collaboration strategies and touch input techniques when dealing with digital objects. In particular, we highlight a number of behaviours of interest, such as how the children would move the same digital object on the table together. We also discuss how the children work in close proximity to each other and dynamically organize their spatial positions in order to work together, as well as establish territory and control. We go on to examine some of the finger-based interaction and manipulation strategies that arise in these contexts. Finally, the paper considers the implications of such behaviours for the deployment of tabletop applications in these particular educational contexts.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Comparison of User Performance in Mixed 2D-3D Multi-Display Environments

  Interact 2013 (Springer IFIP )

  Stereoscopic displays and volumetric 3D displays capable of delivering 3D views have in use for many years. These standalone displays have been investigated in detail for their impact on users’ viewing experiences. Effects like aesthenopia and nausea are well-known for flat-screen based stereoscopic displays. However, these devices have not been tested in the context of multi-display environments (MDEs). The performance cost of repetitive switching between a 3D (stereo or volumetric) display and a standard 2D display are not known. In this paper, we perform a thorough user study where we investigate the effects of using such 3D displays within the context of a MDE. We report on our findings and discuss the implications of the same on designs involving such hybrid setups. Our experiments show that in the condition involving two 2D displays which allow for motion parallax and perspective correction, the participants performed the task the fastest.

• Portallax: Bringing 3D Displays Capabilities to Handhelds

  MobileHCI 2014 ACM

  We present Portallax, a clip-on technology to retrofit mobile devices with 3D display capabilities. Available technologies (e.g. Nintendo 3DS or LG Optimus) and clip-on solutions (e.g. 3DeeSlide and Grilli3D) force users to have a fixed head and device positions. This is contradictory to the nature of a mobile scenario, and limits the usage of interaction techniques such as tilting the device to control a game. Portallax uses an actuated parallax barrier and face tracking to realign the barrier's position to the user's position. This allows us to provide stereo, motion parallax and perspective correction cues in 60 degrees in front of the device. Our optimized design of the barrier minimizes colour distortion, maximizes resolution and produces bigger view-zones, which support ~81% of adults' interpupillary distances and allow eye tracking implemented with the front camera. We present a reference implementation, evaluate its key features and provide example applications illustrating the potential of Portallax.

• Spending Time with Money: from shared values to social connectivity

  ACM

  There is a rapidly growing momentum driving the development of mobile payment systems for co-present interactions, using near-field communication on smartphones and contactless payment systems. The design (and marketing) imperative for this is to enable faster, simpler, effortless and secure transactions, yet our evidence shows that this focus on reducing transactional friction may ignore other important features around making payments. We draw from empirical data to consider user interactions around financial exchanges made on mobile phones. Our findings examine how the practices around making payments support people in making connections, to other people, to their communities, to the places they move through, to their environment, and to what they consume. While these social and community bonds shape the kinds of interactions that become possible, they also shape how users feel about, and act on, the values that they hold with their co-users. We draw implications for future payment systems that make use of community connections, build trust, leverage transactional latency, and generate opportunities for rich social interactions.

• PiVOT : Personalized View-Overlays for Tabletops

  25th Annual ACM Symposium on User Interface Software and Technology

  PiVOT is a tabletop system aimed at supporting mixed-focus collaborative tasks. Through two view-zones, PiVOT provides personalized views to individual users while presenting an unaffected and unobstructed shared view to all users. The system supports multiple personalized views which can be present at the same spatial location and yet be only visible to the users it belongs to. PiVOT also allows the creation of personal views that can be either 2D or (auto-stereoscopic) 3D images. [to appear in UIST 2012 http://www.acm.org/uist/uist2012/] PiVOT is a result of exploration of different designs meant to address the seemingly opposing challenges of shared and personalized views.A sample prototype has been implemented and evaluated to validate our design ideas and can run a set of sample applications that demonstrate the utility of the system.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Temporal, Affective, and Embodied Characteristics of Taste Experiences: A Framework for Design

  CHI '14 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

• D-FLIP: Dynamic & Flexible Interactive PhotoShow

  In proceedings of Advances in Computer Entertainment (ACE 2013)

• Online Single Trial Ern Detection As An Interaction Aid In HCI Applications

  CHI 2011 Workshop on Brain and Body Interfaces: Designing for Meaningful Interaction

  Error-related negativity (ERN) is a form of an Event Related Potential signal which can be triggered in the brain when a user either makes a mistake or the application behaves differently from the expectation of the user. The first step to harness the benefits of ERN in HCI applications is to detect the patterns in real-time on a single trial basis. In this paper we present our initial results in detecting ERN. Using a logistic regression technique, we have achieved a 70% recognition rate of erroneous and correct single trials. We then explored several designs, e.g. using ERN to help a user in the moment of bad decision in a map navigation task. Through multiple designs and careful user testing, we aim to identify guidelines and design principles that can help HCI researchers to include ERN as an interaction aid in their applications.

• Modeling steering within above-the-surface interaction layers

  CHI '07 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

  A Mathematical Model for Steering above Tabletops.

• Ultrahaptics: multi-point mid-air haptic feedback for touch surfaces

  Proceedings of the 26th annual ACM symposium on User Interface Software and Technology

  We introduce UltraHaptics, a system designed to provide multi-point haptic feedback above an interactive surface. UltraHaptics employs focused ultrasound to project discrete points of haptic feedback through the display and directly on to users' unadorned hands. We investigate the desirable properties of an acoustically transparent display and demonstrate that the system is capable of creating multiple localised points of feedback in mid-air. Through psychophysical experiments we show that feedback points with different tactile properties can be identified at smaller separations. We also show that users are able to distinguish between different vibration frequencies of non-contact points with training. Finally, we explore a number of exciting new interaction possibilities that UltraHaptics provides.

• Group Interaction on Interactive Multi-touch Tables by Children in India

  Proceedings of the 11th International Conference on Interaction Design and Children

  Interactive tables provide multi-touch capabilities that can enable children to collaborate face-to-face simultaneously. In this paper we extend existing understanding of children's use of interactive tabletops by examining their use by school children in a school in Delhi, India. In the study, we explore how the school children exhibit particular types of collaboration strategies and touch input techniques when dealing with digital objects. In particular, we highlight a number of behaviours of interest, such as how the children would move the same digital object on the table together. We also discuss how the children work in close proximity to each other and dynamically organize their spatial positions in order to work together, as well as establish territory and control. We go on to examine some of the finger-based interaction and manipulation strategies that arise in these contexts. Finally, the paper considers the implications of such behaviours for the deployment of tabletop applications in these particular educational contexts.

• Talking about tactile experiences

  CHI '13 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

  A common problem with designing applications with tactile interfaces is the lack of a vocabulary that allows one to communicate about haptics. We present a human-experiential vocabulary for tactile experiences.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Comparison of User Performance in Mixed 2D-3D Multi-Display Environments

  Interact 2013 (Springer IFIP )

  Stereoscopic displays and volumetric 3D displays capable of delivering 3D views have in use for many years. These standalone displays have been investigated in detail for their impact on users’ viewing experiences. Effects like aesthenopia and nausea are well-known for flat-screen based stereoscopic displays. However, these devices have not been tested in the context of multi-display environments (MDEs). The performance cost of repetitive switching between a 3D (stereo or volumetric) display and a standard 2D display are not known. In this paper, we perform a thorough user study where we investigate the effects of using such 3D displays within the context of a MDE. We report on our findings and discuss the implications of the same on designs involving such hybrid setups. Our experiments show that in the condition involving two 2D displays which allow for motion parallax and perspective correction, the participants performed the task the fastest.

• Portallax: Bringing 3D Displays Capabilities to Handhelds

  MobileHCI 2014 ACM

  We present Portallax, a clip-on technology to retrofit mobile devices with 3D display capabilities. Available technologies (e.g. Nintendo 3DS or LG Optimus) and clip-on solutions (e.g. 3DeeSlide and Grilli3D) force users to have a fixed head and device positions. This is contradictory to the nature of a mobile scenario, and limits the usage of interaction techniques such as tilting the device to control a game. Portallax uses an actuated parallax barrier and face tracking to realign the barrier's position to the user's position. This allows us to provide stereo, motion parallax and perspective correction cues in 60 degrees in front of the device. Our optimized design of the barrier minimizes colour distortion, maximizes resolution and produces bigger view-zones, which support ~81% of adults' interpupillary distances and allow eye tracking implemented with the front camera. We present a reference implementation, evaluate its key features and provide example applications illustrating the potential of Portallax.

• Spending Time with Money: from shared values to social connectivity

  ACM

  There is a rapidly growing momentum driving the development of mobile payment systems for co-present interactions, using near-field communication on smartphones and contactless payment systems. The design (and marketing) imperative for this is to enable faster, simpler, effortless and secure transactions, yet our evidence shows that this focus on reducing transactional friction may ignore other important features around making payments. We draw from empirical data to consider user interactions around financial exchanges made on mobile phones. Our findings examine how the practices around making payments support people in making connections, to other people, to their communities, to the places they move through, to their environment, and to what they consume. While these social and community bonds shape the kinds of interactions that become possible, they also shape how users feel about, and act on, the values that they hold with their co-users. We draw implications for future payment systems that make use of community connections, build trust, leverage transactional latency, and generate opportunities for rich social interactions.

• PiVOT : Personalized View-Overlays for Tabletops

  25th Annual ACM Symposium on User Interface Software and Technology

  PiVOT is a tabletop system aimed at supporting mixed-focus collaborative tasks. Through two view-zones, PiVOT provides personalized views to individual users while presenting an unaffected and unobstructed shared view to all users. The system supports multiple personalized views which can be present at the same spatial location and yet be only visible to the users it belongs to. PiVOT also allows the creation of personal views that can be either 2D or (auto-stereoscopic) 3D images. [to appear in UIST 2012 http://www.acm.org/uist/uist2012/] PiVOT is a result of exploration of different designs meant to address the seemingly opposing challenges of shared and personalized views.A sample prototype has been implemented and evaluated to validate our design ideas and can run a set of sample applications that demonstrate the utility of the system.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Temporal, Affective, and Embodied Characteristics of Taste Experiences: A Framework for Design

  CHI '14 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

• D-FLIP: Dynamic & Flexible Interactive PhotoShow

  In proceedings of Advances in Computer Entertainment (ACE 2013)

• Online Single Trial Ern Detection As An Interaction Aid In HCI Applications

  CHI 2011 Workshop on Brain and Body Interfaces: Designing for Meaningful Interaction

  Error-related negativity (ERN) is a form of an Event Related Potential signal which can be triggered in the brain when a user either makes a mistake or the application behaves differently from the expectation of the user. The first step to harness the benefits of ERN in HCI applications is to detect the patterns in real-time on a single trial basis. In this paper we present our initial results in detecting ERN. Using a logistic regression technique, we have achieved a 70% recognition rate of erroneous and correct single trials. We then explored several designs, e.g. using ERN to help a user in the moment of bad decision in a map navigation task. Through multiple designs and careful user testing, we aim to identify guidelines and design principles that can help HCI researchers to include ERN as an interaction aid in their applications.

• Modeling steering within above-the-surface interaction layers

  CHI '07 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

  A Mathematical Model for Steering above Tabletops.

• Ultrahaptics: multi-point mid-air haptic feedback for touch surfaces

  Proceedings of the 26th annual ACM symposium on User Interface Software and Technology

  We introduce UltraHaptics, a system designed to provide multi-point haptic feedback above an interactive surface. UltraHaptics employs focused ultrasound to project discrete points of haptic feedback through the display and directly on to users' unadorned hands. We investigate the desirable properties of an acoustically transparent display and demonstrate that the system is capable of creating multiple localised points of feedback in mid-air. Through psychophysical experiments we show that feedback points with different tactile properties can be identified at smaller separations. We also show that users are able to distinguish between different vibration frequencies of non-contact points with training. Finally, we explore a number of exciting new interaction possibilities that UltraHaptics provides.

• Group Interaction on Interactive Multi-touch Tables by Children in India

  Proceedings of the 11th International Conference on Interaction Design and Children

  Interactive tables provide multi-touch capabilities that can enable children to collaborate face-to-face simultaneously. In this paper we extend existing understanding of children's use of interactive tabletops by examining their use by school children in a school in Delhi, India. In the study, we explore how the school children exhibit particular types of collaboration strategies and touch input techniques when dealing with digital objects. In particular, we highlight a number of behaviours of interest, such as how the children would move the same digital object on the table together. We also discuss how the children work in close proximity to each other and dynamically organize their spatial positions in order to work together, as well as establish territory and control. We go on to examine some of the finger-based interaction and manipulation strategies that arise in these contexts. Finally, the paper considers the implications of such behaviours for the deployment of tabletop applications in these particular educational contexts.

• Talking about tactile experiences

  CHI '13 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

  A common problem with designing applications with tactile interfaces is the lack of a vocabulary that allows one to communicate about haptics. We present a human-experiential vocabulary for tactile experiences.

• Opportunities and Challenges for Data Physicalization

  CHI 2015 ACM

  Physical representations of data have existed for thousands of years. Yet it is now that advances in digital fabrication, actuated tangible interfaces, and shape-changing displays are spurring an emerging area of research that we call Data Physicalization. It aims to help people explore, understand, and communicate data using computer-supported physical data representations. We call these representations physicalizations, analogously to visualizations – their purely visual counterpart. In this article, we go beyond the focused research questions addressed so far by delineating the research area, synthesizing its open challenges, and laying out a research agenda.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Comparison of User Performance in Mixed 2D-3D Multi-Display Environments

  Interact 2013 (Springer IFIP )

  Stereoscopic displays and volumetric 3D displays capable of delivering 3D views have in use for many years. These standalone displays have been investigated in detail for their impact on users’ viewing experiences. Effects like aesthenopia and nausea are well-known for flat-screen based stereoscopic displays. However, these devices have not been tested in the context of multi-display environments (MDEs). The performance cost of repetitive switching between a 3D (stereo or volumetric) display and a standard 2D display are not known. In this paper, we perform a thorough user study where we investigate the effects of using such 3D displays within the context of a MDE. We report on our findings and discuss the implications of the same on designs involving such hybrid setups. Our experiments show that in the condition involving two 2D displays which allow for motion parallax and perspective correction, the participants performed the task the fastest.

• Portallax: Bringing 3D Displays Capabilities to Handhelds

  MobileHCI 2014 ACM

  We present Portallax, a clip-on technology to retrofit mobile devices with 3D display capabilities. Available technologies (e.g. Nintendo 3DS or LG Optimus) and clip-on solutions (e.g. 3DeeSlide and Grilli3D) force users to have a fixed head and device positions. This is contradictory to the nature of a mobile scenario, and limits the usage of interaction techniques such as tilting the device to control a game. Portallax uses an actuated parallax barrier and face tracking to realign the barrier's position to the user's position. This allows us to provide stereo, motion parallax and perspective correction cues in 60 degrees in front of the device. Our optimized design of the barrier minimizes colour distortion, maximizes resolution and produces bigger view-zones, which support ~81% of adults' interpupillary distances and allow eye tracking implemented with the front camera. We present a reference implementation, evaluate its key features and provide example applications illustrating the potential of Portallax.

• Spending Time with Money: from shared values to social connectivity

  ACM

  There is a rapidly growing momentum driving the development of mobile payment systems for co-present interactions, using near-field communication on smartphones and contactless payment systems. The design (and marketing) imperative for this is to enable faster, simpler, effortless and secure transactions, yet our evidence shows that this focus on reducing transactional friction may ignore other important features around making payments. We draw from empirical data to consider user interactions around financial exchanges made on mobile phones. Our findings examine how the practices around making payments support people in making connections, to other people, to their communities, to the places they move through, to their environment, and to what they consume. While these social and community bonds shape the kinds of interactions that become possible, they also shape how users feel about, and act on, the values that they hold with their co-users. We draw implications for future payment systems that make use of community connections, build trust, leverage transactional latency, and generate opportunities for rich social interactions.

• PiVOT : Personalized View-Overlays for Tabletops

  25th Annual ACM Symposium on User Interface Software and Technology

  PiVOT is a tabletop system aimed at supporting mixed-focus collaborative tasks. Through two view-zones, PiVOT provides personalized views to individual users while presenting an unaffected and unobstructed shared view to all users. The system supports multiple personalized views which can be present at the same spatial location and yet be only visible to the users it belongs to. PiVOT also allows the creation of personal views that can be either 2D or (auto-stereoscopic) 3D images. [to appear in UIST 2012 http://www.acm.org/uist/uist2012/] PiVOT is a result of exploration of different designs meant to address the seemingly opposing challenges of shared and personalized views.A sample prototype has been implemented and evaluated to validate our design ideas and can run a set of sample applications that demonstrate the utility of the system.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Temporal, Affective, and Embodied Characteristics of Taste Experiences: A Framework for Design

  CHI '14 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

• D-FLIP: Dynamic & Flexible Interactive PhotoShow

  In proceedings of Advances in Computer Entertainment (ACE 2013)

• Online Single Trial Ern Detection As An Interaction Aid In HCI Applications

  CHI 2011 Workshop on Brain and Body Interfaces: Designing for Meaningful Interaction

  Error-related negativity (ERN) is a form of an Event Related Potential signal which can be triggered in the brain when a user either makes a mistake or the application behaves differently from the expectation of the user. The first step to harness the benefits of ERN in HCI applications is to detect the patterns in real-time on a single trial basis. In this paper we present our initial results in detecting ERN. Using a logistic regression technique, we have achieved a 70% recognition rate of erroneous and correct single trials. We then explored several designs, e.g. using ERN to help a user in the moment of bad decision in a map navigation task. Through multiple designs and careful user testing, we aim to identify guidelines and design principles that can help HCI researchers to include ERN as an interaction aid in their applications.

• Modeling steering within above-the-surface interaction layers

  CHI '07 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

  A Mathematical Model for Steering above Tabletops.

• Ultrahaptics: multi-point mid-air haptic feedback for touch surfaces

  Proceedings of the 26th annual ACM symposium on User Interface Software and Technology

  We introduce UltraHaptics, a system designed to provide multi-point haptic feedback above an interactive surface. UltraHaptics employs focused ultrasound to project discrete points of haptic feedback through the display and directly on to users' unadorned hands. We investigate the desirable properties of an acoustically transparent display and demonstrate that the system is capable of creating multiple localised points of feedback in mid-air. Through psychophysical experiments we show that feedback points with different tactile properties can be identified at smaller separations. We also show that users are able to distinguish between different vibration frequencies of non-contact points with training. Finally, we explore a number of exciting new interaction possibilities that UltraHaptics provides.

• Group Interaction on Interactive Multi-touch Tables by Children in India

  Proceedings of the 11th International Conference on Interaction Design and Children

  Interactive tables provide multi-touch capabilities that can enable children to collaborate face-to-face simultaneously. In this paper we extend existing understanding of children's use of interactive tabletops by examining their use by school children in a school in Delhi, India. In the study, we explore how the school children exhibit particular types of collaboration strategies and touch input techniques when dealing with digital objects. In particular, we highlight a number of behaviours of interest, such as how the children would move the same digital object on the table together. We also discuss how the children work in close proximity to each other and dynamically organize their spatial positions in order to work together, as well as establish territory and control. We go on to examine some of the finger-based interaction and manipulation strategies that arise in these contexts. Finally, the paper considers the implications of such behaviours for the deployment of tabletop applications in these particular educational contexts.

• Talking about tactile experiences

  CHI '13 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

  A common problem with designing applications with tactile interfaces is the lack of a vocabulary that allows one to communicate about haptics. We present a human-experiential vocabulary for tactile experiences.

• Opportunities and Challenges for Data Physicalization

  CHI 2015 ACM

  Physical representations of data have existed for thousands of years. Yet it is now that advances in digital fabrication, actuated tangible interfaces, and shape-changing displays are spurring an emerging area of research that we call Data Physicalization. It aims to help people explore, understand, and communicate data using computer-supported physical data representations. We call these representations physicalizations, analogously to visualizations – their purely visual counterpart. In this article, we go beyond the focused research questions addressed so far by delineating the research area, synthesizing its open challenges, and laying out a research agenda.

• Error Related Negativity in Observing Interactive Tasks

  CHI '14 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

  Error Related Negativity is triggered when a user either makes a mistake or the application behaves differently from their expectation. It can also appear while observing another user making a mistake. This paper investigates ERN in collaborative settings where observing another user (the executer) perform a task is typical and then explores its applicability to HCI. We first show that ERN can be detected on signals captured by commodity EEG headsets like an Emotiv headset when observing another person perform a typical multiple-choice reaction time task. We then investigate the anticipation effects by detecting ERN in the time interval when an executer is reaching towards an answer. We show that we can detect this signal with both a clinical EEG device and with an Emotiv headset. Our results show that online single trial detection is possible using both headsets during tasks that are typical of collaborative interactive applications. However there is a trade-off between the detection speed and the quality/prices of the headsets. Based on the results, we discuss and present several HCI scenarios for use of ERN in observing tasks and collaborative settings.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Comparison of User Performance in Mixed 2D-3D Multi-Display Environments

  Interact 2013 (Springer IFIP )

  Stereoscopic displays and volumetric 3D displays capable of delivering 3D views have in use for many years. These standalone displays have been investigated in detail for their impact on users’ viewing experiences. Effects like aesthenopia and nausea are well-known for flat-screen based stereoscopic displays. However, these devices have not been tested in the context of multi-display environments (MDEs). The performance cost of repetitive switching between a 3D (stereo or volumetric) display and a standard 2D display are not known. In this paper, we perform a thorough user study where we investigate the effects of using such 3D displays within the context of a MDE. We report on our findings and discuss the implications of the same on designs involving such hybrid setups. Our experiments show that in the condition involving two 2D displays which allow for motion parallax and perspective correction, the participants performed the task the fastest.

• Portallax: Bringing 3D Displays Capabilities to Handhelds

  MobileHCI 2014 ACM

  We present Portallax, a clip-on technology to retrofit mobile devices with 3D display capabilities. Available technologies (e.g. Nintendo 3DS or LG Optimus) and clip-on solutions (e.g. 3DeeSlide and Grilli3D) force users to have a fixed head and device positions. This is contradictory to the nature of a mobile scenario, and limits the usage of interaction techniques such as tilting the device to control a game. Portallax uses an actuated parallax barrier and face tracking to realign the barrier's position to the user's position. This allows us to provide stereo, motion parallax and perspective correction cues in 60 degrees in front of the device. Our optimized design of the barrier minimizes colour distortion, maximizes resolution and produces bigger view-zones, which support ~81% of adults' interpupillary distances and allow eye tracking implemented with the front camera. We present a reference implementation, evaluate its key features and provide example applications illustrating the potential of Portallax.

• Spending Time with Money: from shared values to social connectivity

  ACM

  There is a rapidly growing momentum driving the development of mobile payment systems for co-present interactions, using near-field communication on smartphones and contactless payment systems. The design (and marketing) imperative for this is to enable faster, simpler, effortless and secure transactions, yet our evidence shows that this focus on reducing transactional friction may ignore other important features around making payments. We draw from empirical data to consider user interactions around financial exchanges made on mobile phones. Our findings examine how the practices around making payments support people in making connections, to other people, to their communities, to the places they move through, to their environment, and to what they consume. While these social and community bonds shape the kinds of interactions that become possible, they also shape how users feel about, and act on, the values that they hold with their co-users. We draw implications for future payment systems that make use of community connections, build trust, leverage transactional latency, and generate opportunities for rich social interactions.

• PiVOT : Personalized View-Overlays for Tabletops

  25th Annual ACM Symposium on User Interface Software and Technology

  PiVOT is a tabletop system aimed at supporting mixed-focus collaborative tasks. Through two view-zones, PiVOT provides personalized views to individual users while presenting an unaffected and unobstructed shared view to all users. The system supports multiple personalized views which can be present at the same spatial location and yet be only visible to the users it belongs to. PiVOT also allows the creation of personal views that can be either 2D or (auto-stereoscopic) 3D images. [to appear in UIST 2012 http://www.acm.org/uist/uist2012/] PiVOT is a result of exploration of different designs meant to address the seemingly opposing challenges of shared and personalized views.A sample prototype has been implemented and evaluated to validate our design ideas and can run a set of sample applications that demonstrate the utility of the system.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Temporal, Affective, and Embodied Characteristics of Taste Experiences: A Framework for Design

  CHI '14 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

• D-FLIP: Dynamic & Flexible Interactive PhotoShow

  In proceedings of Advances in Computer Entertainment (ACE 2013)

• Online Single Trial Ern Detection As An Interaction Aid In HCI Applications

  CHI 2011 Workshop on Brain and Body Interfaces: Designing for Meaningful Interaction

  Error-related negativity (ERN) is a form of an Event Related Potential signal which can be triggered in the brain when a user either makes a mistake or the application behaves differently from the expectation of the user. The first step to harness the benefits of ERN in HCI applications is to detect the patterns in real-time on a single trial basis. In this paper we present our initial results in detecting ERN. Using a logistic regression technique, we have achieved a 70% recognition rate of erroneous and correct single trials. We then explored several designs, e.g. using ERN to help a user in the moment of bad decision in a map navigation task. Through multiple designs and careful user testing, we aim to identify guidelines and design principles that can help HCI researchers to include ERN as an interaction aid in their applications.

• Modeling steering within above-the-surface interaction layers

  CHI '07 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

  A Mathematical Model for Steering above Tabletops.

• Ultrahaptics: multi-point mid-air haptic feedback for touch surfaces

  Proceedings of the 26th annual ACM symposium on User Interface Software and Technology

  We introduce UltraHaptics, a system designed to provide multi-point haptic feedback above an interactive surface. UltraHaptics employs focused ultrasound to project discrete points of haptic feedback through the display and directly on to users' unadorned hands. We investigate the desirable properties of an acoustically transparent display and demonstrate that the system is capable of creating multiple localised points of feedback in mid-air. Through psychophysical experiments we show that feedback points with different tactile properties can be identified at smaller separations. We also show that users are able to distinguish between different vibration frequencies of non-contact points with training. Finally, we explore a number of exciting new interaction possibilities that UltraHaptics provides.

• Group Interaction on Interactive Multi-touch Tables by Children in India

  Proceedings of the 11th International Conference on Interaction Design and Children

  Interactive tables provide multi-touch capabilities that can enable children to collaborate face-to-face simultaneously. In this paper we extend existing understanding of children's use of interactive tabletops by examining their use by school children in a school in Delhi, India. In the study, we explore how the school children exhibit particular types of collaboration strategies and touch input techniques when dealing with digital objects. In particular, we highlight a number of behaviours of interest, such as how the children would move the same digital object on the table together. We also discuss how the children work in close proximity to each other and dynamically organize their spatial positions in order to work together, as well as establish territory and control. We go on to examine some of the finger-based interaction and manipulation strategies that arise in these contexts. Finally, the paper considers the implications of such behaviours for the deployment of tabletop applications in these particular educational contexts.

• Talking about tactile experiences

  CHI '13 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

  A common problem with designing applications with tactile interfaces is the lack of a vocabulary that allows one to communicate about haptics. We present a human-experiential vocabulary for tactile experiences.

• Opportunities and Challenges for Data Physicalization

  CHI 2015 ACM

  Physical representations of data have existed for thousands of years. Yet it is now that advances in digital fabrication, actuated tangible interfaces, and shape-changing displays are spurring an emerging area of research that we call Data Physicalization. It aims to help people explore, understand, and communicate data using computer-supported physical data representations. We call these representations physicalizations, analogously to visualizations – their purely visual counterpart. In this article, we go beyond the focused research questions addressed so far by delineating the research area, synthesizing its open challenges, and laying out a research agenda.

• Error Related Negativity in Observing Interactive Tasks

  CHI '14 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

  Error Related Negativity is triggered when a user either makes a mistake or the application behaves differently from their expectation. It can also appear while observing another user making a mistake. This paper investigates ERN in collaborative settings where observing another user (the executer) perform a task is typical and then explores its applicability to HCI. We first show that ERN can be detected on signals captured by commodity EEG headsets like an Emotiv headset when observing another person perform a typical multiple-choice reaction time task. We then investigate the anticipation effects by detecting ERN in the time interval when an executer is reaching towards an answer. We show that we can detect this signal with both a clinical EEG device and with an Emotiv headset. Our results show that online single trial detection is possible using both headsets during tasks that are typical of collaborative interactive applications. However there is a trade-off between the detection speed and the quality/prices of the headsets. Based on the results, we discuss and present several HCI scenarios for use of ERN in observing tasks and collaborative settings.

• Dynamic Spatial Positioning: Physical Collaboration around Interactive Table by Children in India

  Interact 2013 (Springer IFIP )

  We present a study of how children demonstrate physicality during collaboration around interactive tables at school. Our results show that children tend to dynamically position themselves around the tabletop area to effect particular social outcomes. These movements around the tabletop allow them to enact coordination strategies in their social interactions with each other to manage their learning and task-based activities. Our analysis indicates the importance of understanding physical strategies and behaviours when designing and deploying interactive tables in classrooms. We discuss how the design of tabletops in school can embrace the extensibility of this technology, providing access for children to shape their own collaboration strategies during learning.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Organic Experiences: (Re)Shaping Interactions with Deformable Displays

  ACM Press - CHI 2013

  Display technology developments mean the next generation of visual output devices will extend beyond the rigid, flat surfaces with which we are familiar to those that the user or the machine can deform. These will allow users to physically push, pull, bend, fold or flex the display and facilitate a range of self-deformation to better represent on-screen content or support new modes of interaction. This workshop will provide a forum to examine, discuss and shape the three primary themes of research in this area: prototyping and implementation, interaction and experience design, and evaluation. It will bring together an interdisciplinary group of academic and industrial researchers to define the current and future challenges of crafting organic user experiences with deformable displays.

• Comparison of User Performance in Mixed 2D-3D Multi-Display Environments

  Interact 2013 (Springer IFIP )

  Stereoscopic displays and volumetric 3D displays capable of delivering 3D views have in use for many years. These standalone displays have been investigated in detail for their impact on users’ viewing experiences. Effects like aesthenopia and nausea are well-known for flat-screen based stereoscopic displays. However, these devices have not been tested in the context of multi-display environments (MDEs). The performance cost of repetitive switching between a 3D (stereo or volumetric) display and a standard 2D display are not known. In this paper, we perform a thorough user study where we investigate the effects of using such 3D displays within the context of a MDE. We report on our findings and discuss the implications of the same on designs involving such hybrid setups. Our experiments show that in the condition involving two 2D displays which allow for motion parallax and perspective correction, the participants performed the task the fastest.

• Portallax: Bringing 3D Displays Capabilities to Handhelds

  MobileHCI 2014 ACM

  We present Portallax, a clip-on technology to retrofit mobile devices with 3D display capabilities. Available technologies (e.g. Nintendo 3DS or LG Optimus) and clip-on solutions (e.g. 3DeeSlide and Grilli3D) force users to have a fixed head and device positions. This is contradictory to the nature of a mobile scenario, and limits the usage of interaction techniques such as tilting the device to control a game. Portallax uses an actuated parallax barrier and face tracking to realign the barrier's position to the user's position. This allows us to provide stereo, motion parallax and perspective correction cues in 60 degrees in front of the device. Our optimized design of the barrier minimizes colour distortion, maximizes resolution and produces bigger view-zones, which support ~81% of adults' interpupillary distances and allow eye tracking implemented with the front camera. We present a reference implementation, evaluate its key features and provide example applications illustrating the potential of Portallax.

• Spending Time with Money: from shared values to social connectivity

  ACM

  There is a rapidly growing momentum driving the development of mobile payment systems for co-present interactions, using near-field communication on smartphones and contactless payment systems. The design (and marketing) imperative for this is to enable faster, simpler, effortless and secure transactions, yet our evidence shows that this focus on reducing transactional friction may ignore other important features around making payments. We draw from empirical data to consider user interactions around financial exchanges made on mobile phones. Our findings examine how the practices around making payments support people in making connections, to other people, to their communities, to the places they move through, to their environment, and to what they consume. While these social and community bonds shape the kinds of interactions that become possible, they also shape how users feel about, and act on, the values that they hold with their co-users. We draw implications for future payment systems that make use of community connections, build trust, leverage transactional latency, and generate opportunities for rich social interactions.

• PiVOT : Personalized View-Overlays for Tabletops

  25th Annual ACM Symposium on User Interface Software and Technology

  PiVOT is a tabletop system aimed at supporting mixed-focus collaborative tasks. Through two view-zones, PiVOT provides personalized views to individual users while presenting an unaffected and unobstructed shared view to all users. The system supports multiple personalized views which can be present at the same spatial location and yet be only visible to the users it belongs to. PiVOT also allows the creation of personal views that can be either 2D or (auto-stereoscopic) 3D images. [to appear in UIST 2012 http://www.acm.org/uist/uist2012/] PiVOT is a result of exploration of different designs meant to address the seemingly opposing challenges of shared and personalized views.A sample prototype has been implemented and evaluated to validate our design ideas and can run a set of sample applications that demonstrate the utility of the system.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Changibles: Analyzing and Designing Shape Changing Constructive Assembly

  CHI 2014

  Advances in shape changing assemblies have been made in reconfiguration algorithms, hardware designs and interaction techniques. However no tools exist for guiding designers in building those modular devices and especially for choosing the shape of the units. The task becomes even more complex when the units themselves can change their shapes to animate the entire assembly. In this paper, we contribute with the first analysis tool which helps the designer to both choose the right subset of forms for the units and to create an assembly with maximum accuracy from the set of given objects. We introduce the concept of Changibles that are interactive wireless units that can reshape themselves and be attached together to create an animated assembly. We present a use case to demonstrate the use of our tool, with an instantiation of six Changibles that are used to construct a pulsing heart assembly.

• Temporal, Affective, and Embodied Characteristics of Taste Experiences: A Framework for Design

  CHI '14 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

• D-FLIP: Dynamic & Flexible Interactive PhotoShow

  In proceedings of Advances in Computer Entertainment (ACE 2013)

• Online Single Trial Ern Detection As An Interaction Aid In HCI Applications

  CHI 2011 Workshop on Brain and Body Interfaces: Designing for Meaningful Interaction

  Error-related negativity (ERN) is a form of an Event Related Potential signal which can be triggered in the brain when a user either makes a mistake or the application behaves differently from the expectation of the user. The first step to harness the benefits of ERN in HCI applications is to detect the patterns in real-time on a single trial basis. In this paper we present our initial results in detecting ERN. Using a logistic regression technique, we have achieved a 70% recognition rate of erroneous and correct single trials. We then explored several designs, e.g. using ERN to help a user in the moment of bad decision in a map navigation task. Through multiple designs and careful user testing, we aim to identify guidelines and design principles that can help HCI researchers to include ERN as an interaction aid in their applications.

• Modeling steering within above-the-surface interaction layers

  CHI '07 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

  A Mathematical Model for Steering above Tabletops.

• Ultrahaptics: multi-point mid-air haptic feedback for touch surfaces

  Proceedings of the 26th annual ACM symposium on User Interface Software and Technology

  We introduce UltraHaptics, a system designed to provide multi-point haptic feedback above an interactive surface. UltraHaptics employs focused ultrasound to project discrete points of haptic feedback through the display and directly on to users' unadorned hands. We investigate the desirable properties of an acoustically transparent display and demonstrate that the system is capable of creating multiple localised points of feedback in mid-air. Through psychophysical experiments we show that feedback points with different tactile properties can be identified at smaller separations. We also show that users are able to distinguish between different vibration frequencies of non-contact points with training. Finally, we explore a number of exciting new interaction possibilities that UltraHaptics provides.

• Group Interaction on Interactive Multi-touch Tables by Children in India

  Proceedings of the 11th International Conference on Interaction Design and Children

  Interactive tables provide multi-touch capabilities that can enable children to collaborate face-to-face simultaneously. In this paper we extend existing understanding of children's use of interactive tabletops by examining their use by school children in a school in Delhi, India. In the study, we explore how the school children exhibit particular types of collaboration strategies and touch input techniques when dealing with digital objects. In particular, we highlight a number of behaviours of interest, such as how the children would move the same digital object on the table together. We also discuss how the children work in close proximity to each other and dynamically organize their spatial positions in order to work together, as well as establish territory and control. We go on to examine some of the finger-based interaction and manipulation strategies that arise in these contexts. Finally, the paper considers the implications of such behaviours for the deployment of tabletop applications in these particular educational contexts.

• Talking about tactile experiences

  CHI '13 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

  A common problem with designing applications with tactile interfaces is the lack of a vocabulary that allows one to communicate about haptics. We present a human-experiential vocabulary for tactile experiences.

• Opportunities and Challenges for Data Physicalization

  CHI 2015 ACM

  Physical representations of data have existed for thousands of years. Yet it is now that advances in digital fabrication, actuated tangible interfaces, and shape-changing displays are spurring an emerging area of research that we call Data Physicalization. It aims to help people explore, understand, and communicate data using computer-supported physical data representations. We call these representations physicalizations, analogously to visualizations – their purely visual counterpart. In this article, we go beyond the focused research questions addressed so far by delineating the research area, synthesizing its open challenges, and laying out a research agenda.

• Error Related Negativity in Observing Interactive Tasks

  CHI '14 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

  Error Related Negativity is triggered when a user either makes a mistake or the application behaves differently from their expectation. It can also appear while observing another user making a mistake. This paper investigates ERN in collaborative settings where observing another user (the executer) perform a task is typical and then explores its applicability to HCI. We first show that ERN can be detected on signals captured by commodity EEG headsets like an Emotiv headset when observing another person perform a typical multiple-choice reaction time task. We then investigate the anticipation effects by detecting ERN in the time interval when an executer is reaching towards an answer. We show that we can detect this signal with both a clinical EEG device and with an Emotiv headset. Our results show that online single trial detection is possible using both headsets during tasks that are typical of collaborative interactive applications. However there is a trade-off between the detection speed and the quality/prices of the headsets. Based on the results, we discuss and present several HCI scenarios for use of ERN in observing tasks and collaborative settings.

• Dynamic Spatial Positioning: Physical Collaboration around Interactive Table by Children in India

  Interact 2013 (Springer IFIP )

  We present a study of how children demonstrate physicality during collaboration around interactive tables at school. Our results show that children tend to dynamically position themselves around the tabletop area to effect particular social outcomes. These movements around the tabletop allow them to enact coordination strategies in their social interactions with each other to manage their learning and task-based activities. Our analysis indicates the importance of understanding physical strategies and behaviours when designing and deploying interactive tables in classrooms. We discuss how the design of tabletops in school can embrace the extensibility of this technology, providing access for children to shape their own collaboration strategies during learning.

• Detecting Error-Related Negativity for Interaction Design

  CHI '12 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

  This paper examines the ability to detect a characteristic brain potential called the Error-Related Negativity (ERN) using off-the-shelf headsets and explores its applicability to HCI. ERN is triggered when a user either makes a mistake or the application behaves differently from their expectation. We first show that ERN can be seen on signals captured by EEG headsets like Emotiv™ when doing a typical multiple choice reaction time (RT) task -- Flanker task. We then present a single-trial online ERN algorithm that works by pre-computing the coefficient matrix of a logistic regression classifier using some data from a multiple choice reaction time task and uses it to classify incoming signals of that task on a single trial of data. We apply it to an interactive selection task that involved users selecting an object under time pressure. Furthermore the study was conducted in a typical office environment with ambient noise. Our results show that online single trial ERN detection is possible using off-the-shelf headsets during tasks that are typical of interactive applications. We then design a Superflick experiment with an integrated module mimicking an ERN detector to evaluate the accuracy of detecting ERN in the context of assisting users in interactive tasks. Based on these results we discuss and present several HCI scenarios for use of ERN.