Design and Optimize a Novel Ergonomic Shoulder of Upper Limb Rehabilitation Robot

Réhabilitations robots are topics that many researchers are interested in. Currently, most of the upperlimb rehabilitation robots use hinge joints to simulate human shoulder joints. This ensures that the robot shoulder joints have the same structure as the ball joints, or the ball joints are capable of lifting / lowering around a center like the famous Armin III model. However, in fact, the shoulder joint orbitis not a circle or a point, which leads to dis comfort for the patient during exercise. This study proposes to improve the shoulder joint design of the upperlimb rehabilitation robot to ensure the trajectory of the robot shoulder center coincides with the trajectory of the human shoulder joint. First, aproposal to design a new robot shoulder joint to have a flexible operating trajectoryaccording to the human shoulder joint willbe made. Next, the kinematic calculations, as well as optimizing the essential dimensions of the structure to ensure continuity, avoid sudden changes between consecutive points on the shoulder joint trajectory. After that, the shoulder joint structure to meet the above model was built. The process of optimization and simulation of the kinematic problem shows that the proposed robot shoulder joints can follow to the shoulder joints of the human arm, the total deviations in the x and y directions of the robot shoulder and the human shoulder joints in the whole The trajectoryis 0.0028mm and 0.0115, respectively.