Harnessing Capacitance for Inter-Robot Latching, Communication, and Power Transfer

A simple and robust inter-module latch is possibly the most important component of a modular robotic system. This report describes a latch based on capacitive coupling which not only provides significant adhesion forces, but can also be used for inter-module power transmission and communication. The key insight that enables electrostatic adhesion to be effective at the macro scale is to combine flexible electrodes with a geometry that uses shear forces to provide adhesion. To measure the effectiveness of our latch we incorporated it into a 28cm x 28cm x 28cm modular robot. The result is a latch which requires almost zero static power and yet can hold over 0.6N/cm2 of latch area.