On-site simultaneous calibration of hysteric and structural parameters for self-sensing robotic tweezers with strain amplified piezoelectric actuators

This paper presents an on-site calibration method for strain amplified piezoelectric actuator driven robotic tweezers. The method obtains parameters of both hysteresis model and structure model at the same time. System modeling is based on the electro-mechanical model of the actuator, the modified Prandtl-Ishlinskii model of hysteresis and the two-port network model of the strain amplification structure. Validation is performed on a tweezer device with three amplification layers and results are presented in this work. An average of 11.5% error in displacement and 13% error in force are observed.