Abstract
This paper introduces a safe exoskeleton powered hand system to augment pinching force of human fingers: an index finger and a thumb. Two items to keep system safety are proposed so that it can generate almost same grasping force as an adult male's. One is from viewpoint of a mechanical design. Most of the assistive force directly affects to a target object to avoid an excessive force affecting a human finger and then a rest affects to it through a human finger to inform magnitude of an assistive force. The other is from a controller design. The system switches two control algorithms based on bioelectrical potential. The system in a power assist control mode generates an assistive force that is proportional to an integral of bioelectrical signal if it can be measured. In following control mode it stops support if the signal is not measured. A wearer stops the support quickly and releases an object intuitively. Basic performance of the system is investigated through some experiments.
