Set Phasers to Stun: Beaming Power and Control to Mobile Robots with Laser Light

Abstract-- We present Phaser, a flexible system that directs narrow-beam laser light to moving robots for concurrent wireless power delivery and communication. We design a semiautomatic calibration procedure to enable fusion of stereo-vision-based 3D robot tracking with high-power beam steering, and a low-power optical communication scheme that reuses the laser light as a data channel. We fabricate a Phaser prototype using off-the-shelf hardware and evaluate its performance with battery-free autonomous robots. We demonstrate Phaser fully powering gram-scale battery-free robots to nearly 2x higher speeds than prior work while simultaneously controlling them to navigate around obstacles and along paths. Code, an open-source design guide, and a demonstration video of Phaser is available at https: //mobilex.cs.columbia.edu/phaser/. Mobile, autonomous robots play an increasingly important role in today's world, with the potential to perform tasks in warehouses, factories, and homes and conduct advanced environmental explorations [1]. However, the significant power needed for locomotion, on-board computation, and communication presents a key barrier to the broader deployment of such robots. Given the energy density of current batteries [2], most autonomous robots today either remain tethered by charging wires or must routinely return to charging stations, reducing deployment time. This problem is exacerbated in miniaturized robots, which cannot support the 100s of milligrams of battery payload [3]-[7] needed for extended operation, even on their milliwatt power budgets.