LightLink: Enhancing Smartwatch Sensing and Actuation Through Visible Light Communication

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.