Embedded Distributed Capacitive Tactile Sensor

Abstract

A novel embedded distributed capacitive tactile sensor system designed to be installed on humanoid robots is presented. It provides pressure and shape information about the contacts with objects and the environment. The system is based on conformable mesh of sensors having triangular shape, interconnected in order to form a networked structure. Each triangle is a flexible substrate allowing the sensor to be conformed to smooth curved surfaces. It provides 12 capacitive measurements and it has three communications ports placed along its sides: one for the input from an adjacent triangle, and the others as outputs toward adjacent triangles. Each triangle is therefore a single sensor module implementing 12 taxels. The measurements are sent to microcontroller boards using serial bus communication links. A microcontroller board set-up and reads the data coming from a group of modules. Every microcontroller board has a CAN-bus link. The spatial resolution of the skin is one sensor every 5mm. The aim of the project is to install the artificial skin on the humanoid robot iCub, for studying control strategy using tactile feedback coming from the whole body, but it can be used for many other different mechatronic applications where distributed pressure information along a surface are required.