An Anthropomorphic Robotic Finger With Innate Human-Finger-Like Biomechanical Advantages Part II: Flexible Tendon Sheath and Grasping Demonstration

The human hand has a fantastic ability to interact with various objects in the dynamic unstructured environment of our daily activities. We believe that this outstanding performance benefits lot from unique biological features musculoskeletal system. In Part I article, bio-inspired anthropomorphic robotic finger was developed, based on which two human-finger-like biomechanical advantages were elaborately investigated, including anisotropic variable stiffness associated ligamentous joints and enlarged feasible force space reticular extensor mechanisms. II, fingertip force-velocity characteristics resulting flexible tendon sheath are studied. It indicates force–velocity workspace can be greatly augmented owing self-adaptive morphing sheaths, showing average improvement 41.2% theoretically 117.5% experimentally compared results 2 mm, 4 6 mm size rigid sheaths. Grasping tests comparisons then conducted four three-fingered hands (one proposed I, one hinge joints, linear extensors, sheaths) six subjects handle flat, rough, soft surfaces. show novel design research could improve grasping success rates hand. Compared test overall sheaths decreases by 10%, 6%, 17%, respectively. have also shown embedded advantages, even without complex control sensory systems, fingers achieve very comparable demonstrations presented, indicating 94% rate achieved fingers. Successfully demonstrating 14 16 grasp types Cutkoskey taxonomy further shows capability