Evaluation of Bend-Twist Coupling in Shape Memory Alloy Integrated Fiber Rubber Composites

Abstract

Advancements in textile technologies such as the integration of wire shaped Shape Memory Alloys (SMAs) on to the fabric with the help of Tailored-Fiber-Placement (TFP) method, and weft insertion of SMAs during manufacturing of textiles using knitting machines are helping to create composites capable of bending deformations without any external loads. These advancements laid the foundations for versatile applications especially in soft robotics. One such application is Interactive Fiber Rubber Composites (IFRC). The aim of this project is to evaluate the bend-twist coupling in the IFRC. The SMA reinforced composite is made of polydimethylsiloxane (PDMS) and has two layers of glass fibers stacked upon one another and joined with the help of TFP machine. This work focuses on the simulation of this approach in ANSYS with the Woodworth & Kaliske material model for SMA. The important feature of this model is that the shape memory effect can be achieved for different profiles of SMA, thus eliminating the necessity for a pre-stretch in contrast to the built-in model. The experimental values are evaluated from Multi-DIC technique, which is capable of determining deformations with respect to all directions. A comparative study with simulation and experimental results of the deformation and twisting angles is carried out. The derived conclusions will be helpful in obtaining and evaluating 3D spatial movements in IFRC structures with multiple joints in the future projects