Exploiting hysteresis in position control: the magnetic shape memory push-push actuator

This paper discusses in details a control design approach for hysteretic systems with dynamics. The framework is quite general to embrace several unconventional actuators. In particular, we here propose a method which allows the exploitation of the particular hysteresis characteristic of a specific class of actuators based on magnetic shape memory alloys, namely the so-called push-push actuators. The exploitation of the hysteresis leads to the reduction of the energy losses for some positioning tasks, and can lead to a more compact design of the actuator and of its driving electronics. Moreover, heating phenomena (which are very influent for magnetic shape memory alloys) are reduced. The validity of the proposed method is verified by several experimental results performed on a prototype of push-push actuator.