Design and Validation of a Tendon-Driven Hybrid Rigid-Soft Three-Finger Gripper for Humanoid Robots

With the widespread application of robotic technology in fields such as intelligent manufacturing and service robots, humanoid robots have become a research focus due to their natural adaptability to human environments. To address the need for lightweight and adaptive robotic grippers, a tendon-driven underactuated three-finger robotic hand with a hybrid rigid-flexible structure is proposed. First, a hybrid rigid-flexible architecture is constructed, and the tendon path layout is optimized. Then, the system's performance is validated through RRT* path planning simulation, achieving six degrees of freedom motion driven by a single motor. Finally, the lightweight design reduces the total weight to only 132 g, an 18% reduction compared to a gear-driven solution, minimizing the impact on the dynamic balance of the host robot, ROBOTIS OP3. Simulation results show that under a 0.76 kg load, the workspace volume of the robotic hand is 2.3 times larger than that of the theoretical rigid model. The gripper can stably grasp irregular objects ranging from 0.2 to 1.5 kg with a success rate of 89.3%, while maintaining the host robot's walking stability during mobile operations (success rate of 92.4%).A reference is provided for the theoretical research and engineering application of tendon-driven robotic grippers.