Figure 1: LightLink enables adding different sensor and actuator add-ons to a smartwatch: (a) shows a person blowing into a bezel mounted alcohol sensor for on-demand breath alcohol level measurement; (b) four button user interface attached to the watch strap for eyes-free interaction; (c) Tilt switch sensor band attached to the forearm to track reps count in exercises; (d) Vibration band attached to the forearm to deliver haptic patterns; (e) LED display add-on attached to the watch strap for quicker and easier viewing of notifications/navigation instructions.

We explore and evaluate single-handed folding interactions suitable for “modified clamshell flip phones” with a full screen touch display that folds in half along the short dimension. Three categories of interactions are identified: only-fold, touch-enhanced fold, and fold-enhanced touch; in which gestures are created using fold direction, fold magnitude, and touch position. A prototype evaluation device is built to resemble clamshell flip phones, but with a modified hinge and spring system to enable folding in both directions. A study investigates performance and preference for 30 fold gestures to discover which are most promising. To demonstrate how folding interactions could be incorporated into flip phone interfaces, applications such as map browsing, text editing, and menu shortcuts are described.

People often have to remove their phone from an inaccessible location like a pocket to view things like notifications and directions. We explore the idea of viewing such information through the fabric of a pocket using low resolution bright LED matrix displays. A survey confirms viewing information on inaccessible phones is desirable, and establishes types of pockets in garments worn by respondents and what objects are typically put in pockets. A technical evaluation validates that LED light can shine through many common garment fabrics. Based on these results, functional hardware prototypes are constructed to demonstrate different form factors of through-fabric display devices, such as a phone, wallet, a key fob, a pen, and earbud headphone case. A simple interaction vocabulary for viewing key information on these devices is described, and the social and technical aspects of the approach are discussed.

We investigate the performance of one-handed touch input on the side of a mobile phone. A first experiment examines grip change and subjective preference when reaching for side targets using different fingers. Results show all locations can be reached with at least one finger, but the thumb and index are most preferred and require less grip change for positions along the sides. Two following experiments examine taps and flicks using the thumb and index finger in a new two-dimensional input space. A side-touch sensor is simulated with a combination of capacitive sensing and motion tracking to distinguish touches on the lower, middle, or upper edges. When tapping, index and thumb speeds are similar with thumb more accurate and comfortable, and the lower edge is most reliable with the middle edge most comfortable. When flicking with the thumb, the upper edge is fast and rated highly.

Squeezing sensations are one of the most common and intimate forms of human contact. In this paper, we investigate HapticClench, a device that generates squeezing sensations using shape memory alloys. We define squeezing feedback in terms of it perceptual properties and conduct a psychophysical evaluation of HapticClench. HapticClench is capable of generating up to four levels of distinguishable load and works well in distracted scenarios. HapticClench has a high spatial acuity and can generate spatial patterns on the wrist that the user can accurately recognize. We also demonstrate the use of HapticClench for communicating gradual progress of an activity, and for generating squeezing sensations using rings and loose bracelets.

Haptic learning of gesture shortcuts has never been explored. In this paper, we investigate haptic learning of a freehand semaphoric finger tap gesture shortcut set using haptic rings. We conduct a two-day study of 30 participants where we couple haptic stimuli with visual and audio stimuli, and compare their learning performance with wholly visual learning. The results indicate that with <30 minutes of learning, haptic learning of finger tap semaphoric gestures is comparable to visual learning and maintains its recall on the second day.