A novel type of compliant, underactuated robotic hand for dexterous grasping. Robotics: Science and Systems

Abstract—We built a highly compliant, underactuated, ro-bust and at the same time dexterous anthropomorphic hand. We evaluate the dexterous grasping capabilities of the hand by implementing the comprehensive Feix taxonomy of human grasps. We assess the dexterity of the opposable thumb using the Kapandji test. We also illustrate the hand’s payload limits and demonstrate the hand’s grasping capabilities in real-world grasping experiments. To support our claim that compliance is advantageous in dexterous grasping, we compare the dimension-ality of control necessary to implement the grasp postures with the dimensionality of the grasp postures themselves. We find that the actuation space is smaller than the posture space and explain the difference with the beneficial effect of compliant interactions between the hand and the grasped object. Additional desirable properties of the hand are derived from its simple and inexpensive manufacturing process based on soft robotics technology: the hand is robust to impact and blunt collisions, inherently safe, and not affected by dirt, dust, or liquids. I