Active and passive multicycle actuation characteristics of shape memory alloy-based adaptive composite structures

Shape memory alloys (SMAs) offer an attractive way to build adaptive structures as their shape changes and remembered their shape under the applied external stimuli. The adaptive composite structures embedded with SMA wires have been developed using the hand layup process. In this work, the experimental investigation of the actuation behaviour of the SMA-based adaptive composite structures was carried out. This is achieved by imposing external active and passive heating. To investigate the actuation behaviour of the SMA-based adaptive composite structure different diameters of SMA wires and their configurations were considered. Based on the trial experiments, a voltage of 6V, a heating time of 5 sec, and a cooling time of 18 sec have been optimized for electrical heating. These heating conditions were used for all the thermomechanical analysis of SMA-based adaptive composite structures and all the samples were tested for multiple cycles of heating and cooling. The maximum deflection of 14 mm was observed for the composite structure embedded with 4 SMA wires of 0.5 mm diameter. Our fundamental study highlights the possibility of using SMA-based adaptive structures in electromechanical systems such as actuators and sensors.