Redundant upper limb exoskeleton robot with passive compliance

Abstract

Enhancing physical Human-Robot Interaction (pHRI) is an important design aspect in upper limb exoskeleton robots. The level of manipulation provided by an exoskeleton robot has a significant effect to perform daily tasks. This paper evaluate performance of a 6 degree of freedom (DoF) upper limb exoskeleton robot. The detailed mechanical design of the robot is presented with the novel features included in order to improve the pHRI. The exoskeleton robot consists of six DoF and two flexible bellow couplings are used to provide translational DoF at wrist and elbow joints. Moreover, flexible bellow couplings are positioned at specific locations in order to enhance the kinematic redundancy. The benefit of compliance due to the flexible bellow coupling at wrist joint of the robot is verified with reference to manipulability variation of the kinematic model of human lower arm.