Hysteresis Control of a (Ba/Sr)Tio3 Based Actuator: a Comparison of Prandtl-Ishlinskii and Nonlinear Compensator Numerical Methods

Abstract The paper presents an experimental study on (Ba,Sr)TiO3 based actuators hysteretic comportment. The purpose of the study is to model the nonlinearity introduced by the actuator's material in positioning systems for better tracking performances and efficient numerical implementation. The classic and modified Prandtl – Ishlinskii techniques are used such that numerical control can be achieved, by using the inverse model of the nonlinearity. This method is compared to a proposed nonlinear compensator based control structure that uses the geometric characteristic of the process, a lookup table and a robust controller. The hysteretic comportment of the material is evaluated for the normal (symmetric hysteretic curve) and extended functioning domain (asymmetric hysteretic curve). The control methods are compared in terms of tracking error, number of operations and used memory from numerical implementation point of view. The results show that the proposed method needs lesser resources only in the case of extended functioning domain while the tracking errors for the two methods are in general of the same magnitude.