Adaptive Fuzzy Sliding-Mode Position Control of a Shape Memory Alloy Actuated System
Shape memory alloy (SMA) actuators are promising for miniature applications. They accomplish the shape memorization via a temperature dependent phase transformation process. Control of SMA actuators is challenging because the actuators exhibit highly hysteresis behavior. This paper presents a fuzzy-based position control scheme for a SMA actuated mass system. The control system consists of an outer-and an inner-control loop. The inner loop controls the temperature of the SMA actuators using a PI controller, whereas the outer loop, which is affected by the hysteresis of the SMA actuators, controls the position. To deal with the hysteresis in the position control loop, an adaptive fuzzy sliding-mode control method is adopted. Experimental results illustrate the success of the proposed control scheme.