Hysteresis compensation for smart actuators using inverse generalized Prandtl-Ishlinskii model

Control of smart actuators is limited due to strong hysteresis effects which affect the accuracy of these actuators in micropositioning applications. In this paper, generalized Prandtl-Ishlinskii hysteresis model and its inverse are presented to characterize and to compensate hysteresis effects in smart actuators, where a generalized symmetric play operator is adopted to form the generalized Prandtl-Ishlinskii model. The capability of the formulated model to characterize hysteresis in smart actuators is demonstrated by comparing its outputs with experimental results obtained from a piezoceramics actuator. Inverse of the generalized Prandtl-Ishlinskii model is also constructed and it can be implemented as a feedforward compensator to migrate the effects of the hysteresis in different types of smart actuators. To improve the robustness and ensure the stability of the closed-loop system, a robust adaptive control is developed considering the system dynamics. The simulation results validate the effectiveness of the proposed approach.