Power-on-Touch: Powering Actuators, Sensors, and Devices during Interaction

We introduce Power-on-Touch, a novel method for powering devices during interaction. Power-on-Touch comprises two main components: (1) a wearable-transmitter attached to the user's body (e.g., fingernail, back of the hand, feet) with wireless power-coils and a battery; and (2) receiver-tags embedded in interactive devices, making them battery-free. Many devices only require power during interaction (e.g., TV remotes, digital calipers). We leverage this interactive opportunity by inductively transferring energy from the user's coil to the device's coil when in close proximity. To achieve this, we engineered receiver-tags and coils, including thin pancake-coils best-suited for wearables and spherical-coils that receive power omnidirectionally. To understand which coils best support a wide range of interactions (e.g., grasping, touching, hovering), we performed technical characterizations, including impedance and 3D efficiency analysis. We believe our technical approach can inspire ubiquitous computing with new ways to scale up the number and diversity of battery-free devices, not just sensors (µWatts) but also actuators (Watts).