Design and Experimental Research of Upper Gravity-Supporting Device on the Upper Limb Rehabilitation Robot

Due to the influence of robot arm’s and patient’s cantilever’s weight a drive motor with large drive torque was required in the design of upper-limb rehabilitation robot. In order to solve this problem, a new gravity-supporting system that combines gas spring and tension spring to provide supporting force was presented. Due to the use of this device in Upper Limb rehabilitation robot, the power and torque fluctuation of the driving motor can be reduced and the security and stability of robot can be increased. First of all, the movement mechanism was designed and the theoretical analysis is given to prove that it can reduce the driving torque of motor effectively. Three dimensional model of the device was created by Pro/E and was imported into ADAMS/view for the dynamic simulation and got the change curves of driving torque on the condition of the supporting device or not . In the end, the experimental data verify the application of the device that extreme driving torque of robot was decreased over 50%.