Reduction of Residual Vibration of Piezoelectric Actuator Driven by Series of Current Pulses

抄録

Stacked piezoelectric actuators are often embedded in magnification mechanisms. Residual vibration frequently deteriorates positioning performance. The authors have proposed a driving method of a piezoelectric actuator using current pulses for high resolution, hysteresis reduction, and good linearity. This paper evaluates the reduction of residual vibration using a current pulse drive with adjustment of pulse patterns dictated by a genetic algorithm. The pulses from the source and the sink were counted as positive and negative, respectively. The displacement was estimated using a simulation based on Martin's model for optimized current pulse intervals. The current pulse drive was compared with the voltage drive by input shaping. Although the residual vibrations were almost the same for both current pulse drive and input shaping voltage drive in the simulations, current pulse drive resulted in smaller vibrations in the experiments. The residual vibration in the higher harmonics was observed in the input shaping drive because no harmonics were considered in the simulation model. The integral of the current pulse decreased the higher frequency components. Then, the higher harmonics were decreased.