Design Analysis And Experimental Study On Variable Stiffness Of Flexible Robot Joint

With more and more service robots and industrial robots cooperate with humanbeings, there is an urgent need for a robot system that is environment friendly and doesnot cause harm when used in cooperation with people. And it is a hot spot and difficultyproblem with the development of robot technology to realize the design and control ofthe security system for the worker in contact with robots interaction at present. It issignificant to do researches on variable stiffness elastic actuator because it can not onlyensure the safety of human in cooperation work with robot but also promote theperformance of robot with complex work. So with the development of service robots andindustrial robots, the variable stiffness of flexible joint has attracted more and moreattention. In this paper, a variable stiffness flexible rotating joint was designed based onthe leaf spring after doing researches on flexible joints.Firstly, the joint stiffness regulation principle was proposed and the theoreticalmodel of variable stiffness elastic actuator was analyzed after reviewing the works ofother researchers. The mechanical structure was designed according to the designrequirements of the joint. Then elastic element was analyzed and designed as it plays animportant role in the performance of the joint. The characteristics of variable stiffnesswas analyzed after establishing the mathematical model of the joint.Secondly, the hardware circuit of the control system was designed based on thephysical structure of the joint, and the control strategy was proposed according to themethod of changing stiffness.Finally, the testing platform for the joint was assembled to verify the correctness ofthe designed control system. And a series of experiments were conducted based on thetesting platform. The characteristic of variable stiffness of the joint was confirmed byanalyzing the experimental data.