Adaptive Tracking Control of a Piezoelectric Micropositioner

In this study, an adaptive tracking control is proposed for trajectory tracking of a piezoelectric micropositioner which is often used to trajectory scanning applications in microscopy. To describe the dynamics of motion of a single-axis piezoelectric micropositioner approximately, a mathematical model composed of a linear differential equation about motion of mechanical systems and a specified hysteresis function is developed. Then, an adaptive tracking control based on this developed model is proposed. The main purpose of the linear differential equation is to describe the motion dynamics of the mechanical component and the specified hysteresis function is to emulate the hysteresis behaviour due to the stacked piezoelectric actuators built-in inside the micropositioner. To validate the proposed control approach, a PC-based control system which uses a laser interferometer as the displacement sensing detector is implemented. Experimental results illustrate the feasibility of the proposed controller for practical applications in trajectory tracking