Adaptive Material Handling System Based on Shape Memory Alloy Actuators

Abstract

In this paper, a shape memory alloy (SMA) based handling system is presented. The gripping system consists of two different actuator systems based on SMA wires. The first one is a reconfigurable end-effector with four independent gripping arms. The second SMA actuator system is a bi-stable SMA actuated vacuum suction cup, of which one is mounted on each of the four arms of the end-effector. While the four independently adjustable gripping arms of the end-effector allow for an adaption to different workpiece geometries like a flat shaped workpiece or a round shaped, spherical workpiece, integrated SMA driven brake mechanisms enable an energy free position holding of the end-effector components. This means that an electric current is only required when the end-effector arms need to be rearranged. This results in a versatile, adaptive and energy-efficient handling system that can replace mostly pneumatically driven state-of-the-art systems in production and assembly industry. No manual adjustment of the gripping system or even exchanging is needed, if an assembly line switches between products with different work piece geometries as a result. The gripping unit is controlled using an external microcontroller and can be mounted on a robot for diverse handling purposes.