Towards grasping in unstructured environments: grasper compliance and configuration optimization

This paper examines the role of grasper compliance and kinematic configuration in environments where object size and location may not be well known. A grasper consisting of a pair of two-link planar fingers with compliant revolute joints was simulated as it passively deflected during contact with a target object. The kinematic configuration and joint stiffness values of the grasper were varied in order to maximize successful grasp range and minimize contact forces for a wide range of target object size. Joint rest angles around 25–45 degrees produced near-optimal results if the stiffness of the base joint was much smaller than the intermediate joint, as confirmed experimentally.