Finite Element Simulations of Shape Memory Alloy Actuators in Adaptive Structures

Abstract

Shape memory alloys possess an inherent actuation capability that makes them attractive as actuators in adaptive structures, especially in applications in which their large strains, high specific work output and potential for structural integration are beneficial. However, the requisite extensive physical testing has slowed development of potential applications and highlighted the need for a simulation tool for feasibility studies. In this study, such a tool has been developed by implementing the Müller-Achenbach-Seelecke shape memory alloy model into a commercial finite element code. The material model is described with particular emphasis on its ability to predict actuatoric performance and suitability for use in the context of a displacement-based finite element framework. The interaction between the material model and the solution algorithm for the global finite element equations is thoroughly investigated with respect to the effect of solution parameters on convergence, computational cost and accuracy. Finally, simulations of several flexible structures actuated by shape memory alloys are presented as examples of the potential of the implementation to analyze practical applications. The implementation represents a versatile and novel tool for the simulation of adaptive structural components using shape memory alloy actuators.