Multiplexed piezoelectric polymer tactile sensor

Abstract

Abstract An electrically multiplexed robotic tactile sensor has been realized using a monolithic silicon‐integrated circuit coupled to a piezoelectric polyvinylidene fluoride (PVDF) film. The integrated circuit incorporates 25 sensor electrodes arranged in a symmetrical 5 × 5 matrix. Each electrode occupies a 600 × 600 m̈m square area, and they are separated from each other by 600 m̈m. A 25‐m̈m thick PVDF film was experimentally determined to be compatible with the fabrication process, and also yielded very favorable tactile sensing performance characteristics. The response of the tactile sensor is essentially linear for loads spanning 0.8 to 60 g force (gmf). The response bandwidth is 33 Hz, the hysteresis level is very small, and crosstalk is not a significant problem. A novel precharge bias scheme has been implemented to stabilize the pre‐ and postload sensor response. A rudimentary tactile object image measurement process was evaluated to recognize the shapes of circular, rectangular, toroidal, and hexagonal loads.