A Large Area Robot Skin Based on Cell-Bridge System

In this paper, we introduce a soft and stretchable robot skin. There are two novel technologies. One is the "cell-bridge system"; a communication system that consists of two dimensional areas called "cells" and signal transmission devices called "bridges". The other is the "nonlinear tactile element"; a sensor element that has a several-centimeter-square sensing area and acquires a contact area in addition to a contact force. The two parameters are obtained from two capacitances in the sensor structure. The elements are also utilized as the cells, and the bridges measure the capacitances. Using soft materials, we can develop a large-area, soft, and stretchable robot skin without long wires. In the array structure, a contact position can be estimated with finer resolution than the size of the sensor element by calculating a spatial centroid from the measured contact forces.