Hybrid artificial muscle underactuated humanoid robotic hand

Abstract

Due to the artificial muscle advantage properties of light weight, low energy consumption and high power to weight ratio, an underactuated humanoid hand was designed with ionic polymer metal composite (IPMC) actuating distal joint unit and shape memory alloy (SMA) actuating unit. The SMA actuating unit could complete compliant enveloping grasping task for daily life goods. The IPMC actuating distal joint unit could complete grasping task for fragile and light weight goods. The SMA actuating unit was fabricated by multi-piece SMA wires in series to increase output displacement and this series part in parallel to increase output force. This SMA actuator possessed both large output displacement and large output force, solving the mutual restrain problem between output displacement and output force of SMA actuator. Finally, the humanoid hand had completed the bottle, the card and other daily life goods grasping task in experiment, which gave a potent demonstration to the grasping effectiveness.