Static stiffness modeling of the prismatic joint of a modular reconfigurable robot

This paper presents a complete static stiffness model of the prismatic joint of a modular reconfigurable robot based on the flnite-element-and-analytical combined method. The stiffness of the mechanical drive system was analyzed, and its tension and compression stiffness, which can be expressed by a formula, was obtained. The stiffness of the mechanical structure was extracted by employing the finite element method. The additional stiffness due to translational motion of the joint was analyzed. Then the comprehensive stiffness of the joint was obtained by combing the above stiffness parts. A simulation, which consists of four working conditions, was conducted, and the results show that the proposed method is valid.