A mathematical model for the strain–temperature hysteresis of shape memory alloy actuators

In this paper, a new hysteresis model based on the limiting loop proximity (L2P) approach is proposed to describe this phenomenon in the strain (ε)–temperature (T) characteristics of shape memory alloy (SMA) actuators including major and minor loops. In order to validate the proposed model, an experimental set-up was especially designed and implemented aim at to determine the ε–T behavior of Ni-Ti SMA wire actuators under constant loads. The obtained results for ε–T loops are presented together with the data calculated with the proposed model. Model simulations have shown good agreement with the experimental data.