Progress towards a smart skin: fabrication and preliminary testing

This paper describes progress towards the development of a force sensitive skin (“smart skin”) capable of measuring force distributions on the human palmer and finger surface. Closely spaced normal force tactile sensing elements in a flexible skin have been successfully designed and fabricated based on silicon piezoresistive effect using MEMS (microelectromechanical systems) techniques. The sensing array consists of five elements each 4.4 mm in diameter, and arranged within a 16 mm circle designed to fit on a human finger tip. Preliminary bench testing shows the sensor performance is excellent with negligible hysteresis and good linearity (R=0.997). Normal loads of up to 180 N have been measured. A shear sensitive tactile sensor prototype was also developed. The preliminary results demonstrate that the prototype can sense both normal and shear forces with good linearity and repeatability