A novel cooperative compensation method to compensate for return stroke of stick-slip piezoelectric actuators

Abstract

With the development of micro-electromechanical systems, high precision actuators with high resolution, fast speed, large load capacity are increasingly required. Thanks to the characteristics of flexible structure, fast step speed, low energy consumption, high resolution and unlimited stroke range, stick-slip actuators have been drawing worldwide attention. Traditionally, stick-slip actuators are driven by sawtooth waveform signals with a slow increase and a fast decrease. Therefore, there is an unavoidable return stroke when fast decrease of the driving signal appears, which reduces driving speed and efficiency. In this paper, a novel cooperative compensation method (CCM) to compensate for return stroke of stick-slip actuators is proposed. It uses two signals of specific initial time gap (ITG) to reduce the return stroke to improve speed. A modified two-layer stick-slip piezoelectric actuator based on a triangular compliant driving mechanism is built. Experimental results show that the CCM can effectively increase step size of the actuator, especially driven under low frequencies. When signal is at 10 Hz, the step size of the actuator With CCM is over 29 times of that with traditional single-PSA-driving method (TSM). The maximum step size with CCM is 4.448 µm at 250 Hz, which is more than 40% of TSM.