Design considerations for moving and rotating fingers in robotic hand

Many robotic hands have few configurations to achieve versatile grasp modes or the proper grasp force wrench, which is necessary for stable grasp. In this paper, design considerations are reported for improving the grasping capabilities of a low-cost and easy-operation three-finger robotic hand. A special planetary gear mechanism has been designed to adjust the position and orientation of two fingers. This novel solution significantly improves the flexibility of a robotic hand in terms of sizes and shapes of objects which can be grasped. Furthermore, both pinching and enveloping grasp configurations can be achieved similarly to human hands. Simulations are performed in Adams environment to show effectiveness of the proposed mechanism design in terms of both kinematic and dynamic performance.