Design and Analysis of a Robot Hand Based on the Combination of Continuous Flexible Finger and Rigid Tendon Drive Fingers

Abstract

As the most important end-effector of the robot, the robot hand determines the performance of the robot to a certain extent. Therefore, the robot hand often needs high degree of flexibility and larg grasping force to complete complex and diverse tasks. However, most of the existing robot hands are usually difficult to meet the above two requirements. Aiming at this problem, a dexterous robot hand driven by tendon ropes was designed in this paper. Its thumb is a continuum flexible finger with a nickel-titanium alloy wire as the center rod, and the remaining four fingers are tendon-driven rigid fingers. This design allows the thumb to adapt to objects of various shapes, so that the entire robot hand is extremely flexible, and the rigid structure of the four fingers can provide an enough grasping force for the robot hand. In this paper, the robot hand was mechanically designed and simulated by simulation software to ensure the reliability of the design. The workspaces of fingers werecalculated by Matlab through the established DH coordinate system and kinematics model of the robot fingers. In this paper, a physical model of the robot hand was made through 3D printing technology, and thin-film pressure sensors are installed at the end of the fingers to measure the grasping force in real time. Finally, various shapes of objects were selected for the grasping operation, which verified the flexibility and enough grasping force of the robot hand.