Stiffness analysis Of 3-DOF spherical joint based on cable-driven humanoid arm

In this paper, the stiffness of 3-DOF (Degree of Freedom) spherical joint robot based on cable-driven humanoid arm is analyzed. By utilizing forward kinematics, the pose of the robot is realized. Then with the analysis of static, the torque balance relationship between cables is realized. On the basis of the analysis of pose and cable tension, the stiffness of 3-DOF spherical joint robot can be analyzed, which mainly includes two parts: the stiffness related to structural parameters and the stiffness related to cable tension. Finally, by utilizing software ADAMS, the numerical simulate is proposed. It concludes that: the stiffness of 3-DOF spherical joint robot is related to the robot pose, cable stiffness and cable tension. When the cable stiffness is low, by changing inner cable tension, it will change the stiffness of the robot. The research results will provide theoretical guidance to tension and stiffness control for robot.