2-DOF Rolling Joint with the Novel Interior Reinforcement Structures

This paper introduces a 2-Degree of Freedom (2-DOF) rolling joint with a modified internal link configuration and the novel interior reinforcement structures that allow the reduced overall size and higher overall joint stiffness. A constant kinematic relationship between links consisting of the mechanism has been discovered through kinematic analysis. Utilizing this kinematic relationship, the novel interior reinforcement structure is added to improve joint stiffness. Furthermore, decreasing the overall size of the joint is accomplished by changing the geometry of the internal links. With these improvements, the new design of the 2-DOF rolling joint is proposed. Experimental results demonstrate an improved joint stiffness of the proposed joint while achieving reduced overall size and an extensive range of motion.