Integrated IPMC/PVDF sensory actuator and its validation in feedback control

Position and/or force feedback is critical in ensuring precise and safe operation of ionic polymer–metal composite (IPMC) actuators in bio/micromanipulation. In this paper the design of an integrated sensory actuator is presented, where polyvinylidene fluoride (PVDF) films are used to provide simultaneous feedback of bending and force outputs of the IPMC actuator. The design adopts differential configurations for sensing, which eliminates corruption of sensing signals by feedthrough of actuation signal or by thermal drift. Experimental results are presented to demonstrate closed-loop control of IPMC bending output based upon the integrated PVDF sensor, together with simultaneous tip force measurement with μN resolution.