Development of a Lightweight Deformable Surface Mechanism (DSM) by Applying Shape-Memory Alloy (SMA) and the Sponge for Handling Objects

In this paper, we present a lightweight Deformable Surface Mechanism (DSM) by applying shape-memory alloy (SMA) and sponge for moving objects as a soft actuator. The SMA is driven by heating and cooling processing with the cur-rent flowing. For the SMA, cooling is a process for recovering to original length which consumes time. In order to decrease the recovering time and making the surface deformable, a sponge sheet is applied in the mechanism. We used the cotton thread to sew the SMA into the sponge to manufacture the mechanism. The DSM contains a multi-triangle structure, and each triangle works as an individual actuation unit. By applying this structure and special sewing technique, the sponge sheet can be deformed in a vertical direction when the SMA contracted. While, when the current is turned off, the SMA can be stretched to the original length by the pushing force generated by the sponge. Therefore, a deformable surface mechanism with a rapid response can be achieved. We simulated the changing of uni-Deformable Surface Mechanism (uniDSM), and the experiments were followed to compare with the analyzed results. Additionally, different objects were examined on the DSM to test the conveyance ability.