Angular trajectory tracking using antagonistic shape memory alloy actuators

This paper presents an actuator for angular trajectory tracking of a beam using shape memory alloy wires in an antagonistic configuration. Antagonistic shape memory alloy actuators use opposing force to create systems capable of producing alternative tracking paths and two-way mechanical work is done in an efficient way. A closed loop PWM based control scheme is designed and implemented experimentally with rotary position sensing. Experimental results show that a shape memory alloy actuated beam in combination with the controller can track any input trajectory signal.