Modeling and Analysis of Stable Contact States in the Anthropomorphic Robotic Hand with Soft Materials and Rigid Structures

Conducting contact state analysis enhances the stability of object grasping by an anthropomorphic robotic hand. The incorporation of soft materials grants the anthropomorphic robotic hand a compliant nature during interactions with objects, which, in turn, poses challenges for accurate contact state analysis. According to the characteristic of the anthropomorphic robotic hand's compliant contact, a kinetostatic modeling method based on the pseudo-rigid-body model is proposed. It can realize the mapping between contact force and driving torque. On this basis, the stable contact states of the anthropomorphic robotic hand under the envelope grasping mode are further analyzed, which are used to reasonably plan the contact position of the anthropomorphic robotic hand before grasping an object. Experimental results validate the efficacy of the proposed approach during grasping and ensure stable contact in the initial grasping stage. It significantly contributes to enhancing the reliability of the anthropomorphic robotic hand's ability to securely grasp objects.