Robust adaptive control of a Magnetic Shape Memory actuator for precise positioning

Due to their outstanding strain capability, Magnetic Shape Memory actuators are a promising technology for positioning systems. Their wide hysteresis and dependence on temperature require a control system capable to cope with time-varying hysteresis as well as other uncertainties. In this paper, we adopt a modified Prandtl-Ishlinskii operator to capture and compensate by inverse model the hysteresis adaptively. A robust adaptive controller based on adaptive bounding techniques is then designed and integrated in order to improve the performance of the adaptive compensator. Experimental results on a 1DOF linear positioning prototype with micrometric precision confirm the effectiveness of the approach.approach.