Electronic hardware design of a low cost tactile sensor device for physical human-robot interactions

This paper proposes a low-cost system, based on the method of Electrical Impedance Tomography (EIT), for data acquisition from soft conductive fabric, for the purposes of designing of robots artificial skin. A simple multiplexer/ demultiplexer circuit is used for retrieving the resistance field from the pair-wised electrodes which inject the electrical current and the electrodes which measure the output voltage from the conductive fabric. A microcontroller governs the injection of current, voltage output patterns and the analog-digital conversion, from the tactile material. After explanation of the EIT method, the electronics corresponding to the data acquisition is presented and the material characteristics are analyzed. The results show that the spatial patterns of the tactile contact can be acquired and localized in real time.