Shape Memory Alloy Actuation Device Design Tool

A design tool for actuation devices was developed to fulfill the engineering need for user-friendly, non-expert-required software to design with shape memory alloys. The SMA design tool streamlines integration by guiding users through an iterative design approach. The design approach involved constructing a simple set of input commands within MATLAB to import into ABAQUS finite element analysis software with a materials subroutine developed for SMAs. Integration between these tools considers both conventional material and unique SMA parameters. In this study, a materials model turned into analytical routines was developed so that empirical data can be used to predict the structural behavior of SMAs in various geometric configurations for use as actuation devices. The tool incorporates a phenomenological-based material model relating martensite volume fraction to the laws of thermodynamics by following guidelines of the classical theory of plasticity. The material model is capable of representing the non-linear behavior caused by the shape memory effect, pseudoelasticity, and solid-state actuation, which is typically not incorporated into most commercially available modeling tools. The results are expressed based on the objectives to (1) Create a robust, easy-to-use geometric nonlinear numerical code for the prediction of shape and structural capability; (2) Interface the code with an accurate material properties predictor code; and (3) Validate against known analytical solutions and experimentally obtained measurements of key precision structures.