Astigmatic Detection System With Feedback Mechanism for Calibrating Driving Waveform of Piezoelectric Actuators

Piezoelectric actuators are used extensively in precision measurement, manufacturing, and manipulation owing to their high resolution, rapid response, and considerable force output. However, the nonlinear characteristics of piezoelectric materials, including hysteresis and creep, increase the complexity to achieve accurate positioning. Common methods rely on creating an inverse model of the actuator to enable linear movement. This study presents a novel calibration method based on an astigmatic detection system for directly measuring the calibrated driving waveform. This method can be applied to various types of piezoelectric actuators and does away with the need for complicated modeling and parameter identification. The experiment section demonstrates the calibration process of a piezoelectric XYZ scanner. The test results reveal that the linearity of the XYZ scanner, driven by the calibrated driving waveforms, closely approximates that of a commercial closed-loop nanopositioner. Additionally, atomic force microscopy images verify that the proposed method significantly mitigates the image distortion caused by the nonlinear behavior of the piezoelectric material.