The invention provides for a power steering assembly and method of actuation for assisting a driver in moving the steerable wheels of a vehicle. The power steering assembly includes a housing that defines a chamber. A steering rod is disposed in the chamber and is longitudinally moveable within the chamber. A shoulder is fixed to the steering rod and has opposing sides. A shaft is supported by the housing and engages the steering rod translating the rotational movement of the shaft into a longitudinal movement of the steering rod. A first actuator and second actuator are disposed in the chamber on opposing sides of the shoulder. The first and second actuators each have an excitable material that is controlled in a series of actuations to advance the actuators in a linear movement for pushing against the shoulder to move the steering rod longitudinally within the chamber.