Digital tactile sensing elements communicating through conductive skin layers

In this paper, we propose a tactile sensing element that communicates through two dimensional conductive skin layers without individual wires. Each tactile element has sensors and signal processors, and it broadcasts coded tactile signals through a couple of conductive layers. Since the conductive layers can be used for both the electrical power supply and the communication, simply sandwiching the chips between the layers completes electrical connection of tactile sensing chips. Since no metal wires exist, the skin is elastic and tough. High-resolution sensor skins can be easily fabricated in various shapes. In addition, because the tactile elements transmit the locally detected stress data with coded signals, we can obtain high-SN-ratio data from a very small sensing element put at a remote location. This paper describes the skin structure, the communication architecture, the structure of the sensing chip, and the results of basic experiments.