Modified Shape Memory Alloy (SMA) Model for SMA Wire Based Actuator Design

A modified phenomenological model for Shape Memory Alloy (SMA) is presented for design of an SMA wire based rotatory actuator. In this model, the forward and reverse transformation functions are derived from two kinds of tests: standard tension test, carried out at constant temperature, and thermal cyclic test under constant force. This model is verified by the measured behavior of NiTi SMA wire. The analytical result by this model agrees well with the measured performance of an NiTi SMA wire based actuator.