Kai-Yin Cheng

FingerPad: private and subtle interaction using fingertips

We present FingerPad, a nail-mounted device that turns the tip of the index finger into a touchpad, allowing private and subtle interaction while on the move. FingerPad enables touch input using magnetic tracking, by adding a Hall sensor grid on the index fingernail, and a magnet on the thumbnail. Since it permits input through the pinch gesture, FingerPad is suitable for private use because the movements of the fingers in a pinch are subtle and are naturally hidden by the hand. Functionally, FingerPad resembles a touchpad, and also allows for eyes-free use. Additionally, since the necessary devices are attached to the nails, FingerPad preserves natural haptic feedback without affecting the native function of the fingertips. Through user study, we analyze the three design factors, namely posture, commitment method and target size, to assess the design of the FingerPad. Though the results show some trade-off among the factors, generally participants achieve 93% accuracy for very small targets (1.2mm-width) in the seated condition, and 92% accuracy for 2.5mm-width targets in the walking condition.

GaussSense: attachable stylus sensing using magnetic sensor grid

This work presents GaussSense, which is a back-of-device sensing technique for enabling input on an arbitrary surface using stylus by exploiting magnetism. A 2mm-thick Hall sensor grid is developed to sense magnets that are embedded in the stylus. Our system can sense the magnetic field that is emitted from the stylus when it is within 2cm of any non-ferromagnetic surface. Attaching the sensor behind an arbitrary thin surface enables the stylus input to be recognized by analyzing the distribution of the applied magnetic field. Attaching the sensor grid to the back of a touchscreen device and incorporating magnets into the corresponding stylus enable the system 1) to distinguish touch events that are caused by a finger from those caused by the stylus, 2) to sense the tilt angle of the stylus and the pressure with which it is applied, and 3) to detect where the stylus hovers over the screen. A pilot study reveals that people were satisfied with the novel sketching experiences based on this system.

iCon: utilizing everyday objects as additional, auxiliary and instant tabletop controllers

This work describes a novel approach to utilizing everyday objects of users as additional, auxiliary, and instant tabletop controllers. Based on this approach, a prototype platform, called iCon, is developed to explore the possible design. Field studies and user studies reveal that utilizing everyday objects such as auxiliary input devices might be appropriate under a multi-task scenario. User studies further demonstrate that daily objects can generally be applied in low precision circumstances, low engagement with selected objects, and medium-to-high frequency of use. The proposed approach allows users to interact with computers while not altering their original work environments.

GaussBits: magnetic tangible bits for portable and occlusion-free near-surface interactions

We present GaussBits, which is a system of the passive magnetic tangible designs that enables 3D tangible interactions in the near-surface space of portable displays. When a thin magnetic sensor grid is attached to the back of the display, the 3D position and partial 3D orientation of the GaussBits can be resolved by the proposed bi-polar magnetic field tracking technique. This portable platform can therefore enrich tangible interactions by extending the design space to the near-surface space. Since non-ferrous materials, such as the users hand, do not occlude the magnetic field, interaction designers can freely incorporate a magnetic unit into an appropriately shaped non-ferrous object to exploit the metaphors of the real-world tasks, and users can freely manipulate the GaussBits by hands or using other non-ferrous tools without causing interference. The presented example applications and the collected feedback from an explorative workshop revealed that this new approach is widely applicable.

SonarWatch: appropriating the forearm as a slider bar

Human bodies become an emerging type of human-computer interfaces recently. Not only because our skin is a surface that is always available and highly accessible, but also the sense of how our body is configured in space allows us to accurately interact with our bodies in an eye-free manner. Hence, this input method is suitable to be applied on extending the interaction space of mobile devices [Harrison et al. 2010] or providing more degrees-of-freedom for enhancing gaming experiences such as Kinect1. Nevertheless, since the additional gesture detector may be obtrusive or not so portable for users, this approach can hardly be applied in everyday life.

GaussBrush: Drawing with Magnetic Stylus

GaussBrush is a magnetic stylus based on GaussSense technology, which utilizes a thin magnetic sensor grid that can be directly attached to the back of the touchscreen device to enhance its stylus input capability. Utilize the enabled features such as discriminating the stylus events from the finger touch events, determining stylus tilt angle and stylus tip s pressure, and locating the position above where the stylus hovers, more natural sketching experiences are provided. In the demonstrated drawing application, a user can use a GaussBrush to draw a stylized stroke by tilting it or stressing the its tip with different levels, use another side of the stylus to erase unwanted strokes, or hover the stylus at a boundary of the display to access an off-screen color swatch from which a new color can be selected. While drawing, the user still can use finger gestures to pan and zoom the canvas. The combination of GaussBrush and GaussSense extends the design space of Pen+Touch interaction.

Grab-carry-release: manipulating physical objects in a real scene through a smart phone

Individuals often discuss how to configure their real world space, such as switching the location of an object, designing furniture layouts or room decorations, shopping for suitable house appliances, or even commanding a robot to perform certain tasks. However, verbal communication is often insufficient to convey the imagined results for such spatial arrangements. Users must occasionally spend considerable efforts in either moving the real objects physically or using photos or videos to composite the mockup to simulate the layout. Nevertheless, those methods are too tedious for real-time communication.

Sewing photos: smooth transition between photos

In this paper, a new smooth slideshow transition effect, Sewing Photos, is proposed while considering both of smooth content transition and smooth camera motion. Comparing to the traditional photo browsing and displaying work, which all focused on presenting splendid visual effects, Sewing Photos emphasizes on the smooth transition process between photos while taking the photo contents into account. Unlike splendid visual effects, the smooth transition tends to provide more comfortable watching experience and are good for a long-term photo displaying. To smooth the content transition, the system finds the similar parts between the photos first, and then decides what kind of camera operations should be applied according to the corresponding regions. After that, a virtual camera path will be generated according to the extracted Region of Interests (ROIs). To make the camera motion smoother, the camera path is generated as a cubic interpolation spline.

MemoIcon: using everyday objects as physical icons

MemoIcon increases productivity with a new interaction method based on pattern recognition and multi-touch techniques. It easily binds virtual information to everyday real objects and transforms them into physical icons that embody virtual tasks as tangible items. Virtual information becomes tangible and physically present.

Tracking magnetics above portable displays

We present a system of the passive magnetic tangible designs that enables 3D tangible interactions above the portable displays. When a thin magnetic sensor grid is attached to the back of the display, the 3D position and partial 3D orientation of the magnetic tangibles, GaussBits, can be resolved by the proposed bi-polar magnetic field tracking technique. The occlusion-free properties of this tracking method also enrich the design of tangible interactions.