A CMOS-MEMS Electromagnetic-Type Tactile Sensor with Polymer-Filler and Chrome-Steel Ball Sensing Interface

Abstract

This study presents the approach to implement an electromagnetic type active wireless CMOS-MEMS tactile sensor. The tactile force applied on sensor will deform the flexible polymer and further cause the displacement of rigid chrome-steel ball. Thus, the magnetic flux and the voltage of sensing coil induced by the driving coil are changed, which are employed to measure the tactile load. The proposed tactile sensor has four merits: (1) flexible polymer filler as spring, (2) rigid chrome-steel ball as movable sensing interface (for loading and introducing magnetic flux change), (3) CMOS chip as sensing unit, and (4) sensitivity is enhanced by increasing the driving voltage. Note: no suspended thin film structures are required. The presented design is implemented by the standard TSM C O.18μm CMOS process. Measurements indicate the sensitivity of tactile sensor (with 5Vpp driving voltage) is O.53mV/N with loading range of 0-2.4N.