Design and characterization of a shape memory alloy based micro-actuator for tactile stimulation

This paper describes the design, modeling and implementation of a novel shape memory alloy (SMA) based micro-actuator intended for high resolution tactile displays. In order to evaluate the characteristics of SMA devices, existing constitutive models are used to predict their dynamic behavior. In particular, thermal and mechanical properties are studied and analyzed. Time domain and force-displacement open loop experimental results are presented to validate simulation performance. The accuracy of the models may be used to design actuators under specifications of dimension, force and speed. Inspired by a simple retractable ballpoint pen-like mechanism, the actuator´s design concept is described in detail. In conclusion, the prototype and preliminary results are presented and discussed.