POSFET II—The Tactile Sensing Chip

Abstract

This chapter extends the research on POSFET devices, presented in previous chapter, toward the tactile sensing system on chip. The tactile sensing chip presented in this chapter comprises of 5×5 array of POSFET devices and two integrated temperature sensors. The size of each POSFET device on the chip is 1 mm2 and the center–center between two adjacent POSFETs is 1.5 mm. With these features, the tactile sensing chips have human fingertip like spatial resolution and spatial acuity. With a 2-D array of POSFETs and the integrated temperature sensors, the tactile sensing chips are capable of measuring dynamic contact forces and the contact temperature. The chips have been extensively tested over wide range of dynamic contact forces and temperatures and the test results are presented. The experiments presented in this chapter have been performed with the aim to examine the collective performance of a set of POSFETs. The reader interested in the electromechanical evaluation of an individual POSFET device may refer to the results presented in the previous chapter. In fact, this chapter is fundamentally linked to previous chapter hence the reader may first go through previous chapter. Since the time the POSFET tactile sensing chips were reported first, they have been redesigned and the new version have POSFETs with integrated readout electronics on the chip. A discussion is also presented in context with the redesigned tactile sensing chip and the future trend in this area. Finally, new application areas of POSFET like devices are discussed.