Adaptive Control for Piezoelectric Positioning System

It was shown that the maximum tracking error caused by the nonlinear hysteresis phenomena can be as much as 10-15% of the traveling path if the piezoelectric actuator was operated in the open voltage driving loop system. Owing to its nonlinear hysteresis effect, the tracking control accuracy of the precision positioning system is difficultly achieved. Hence, it is desirable to take hysteresis effect into consideration for improving the output tracking performance. In this paper, a model reference adaptive controller design based on hyperstability theory is constructed for a moving stage driven by a piezoelectric actuator. Some simulation results are given to show that the proposed control scheme has a satisfactory output tracking performance in the precision positioning system. The controlled system still can have an excellent output tracking performance even in the presence of system disturbance