Experimental Implementation of Opposed SMA Wires for Actuator Control

Shape Memory Alloys (SMA) have shown their potential as linear actuators. The study conducted here investigates the use of SMA wires as linear actuators for the control of a rotational actuator. The SMA wires are attached to the sides of the actuator to generate opposing forces which are used to control the position of the actuator. In this study the capabilities of this mechanism are demonstrated through tracking of a control path. This mechanism also serves to highlight many effects of SMA wires not commonly discussed: the interaction of opposing hysteresis curves and their effects on the trajectory of the system, the effects of accelerated cooling rates on the hysteresis curves of SMA wires, and the benefits to response time because of the opposing SMA wires.