Modified Brinson model as an equivalent one-dimensional constitutive equation of SMA spring

Shape Memory Alloy (SMA) spring has great potential as a component of compact actuating system. Trade-off between recovery force and deformation range due to phase transformation is possible through the control of spring design parameters such as spring diameter. Deformation behavior of SMA spring is complicated function in three-dimensional space because its behavior is a combination of torsion, bending and stretching action. Therefore, three dimensional analysis of SMA spring is the most accurate simulation procedure. In this paper, modified one-dimensional Brinson model for SMA spring is proposed for more efficient and accurate simulation. In addition, numerical simulation of SMA spring is validated by comparing it with the results of experiment.