Design And Kinematic Performance Analysis Of Cooperative Motion Mechanism Of Exoskeleton Shoulder Rehabilitation Robot

With the gradual deterioration of aging in China,more and more stroke patients are suffering from symptoms of stroke,which are generally manifested as functional injury of different degrees,among which,the most common is the functional injury of the upper limb.The upper limbs play an important role in everyday life,from eating and drinking to carrying heavy objects.Rehabilitation of stroke patients is a problem that cannot be ignored.Traditional physical rehabilitation training requires physiotherapists to have rich professional knowledge and experience.With the increase in the number of patients,the number of physiotherapists is seriously insufficient.In this thesis,a five-degree of freedom exoskeleton shoulder rehabilitation robot with light weight,easy to move and kinematic cooperation is designed.The main research contents are as follows:The complex structure of the shoulder is analyzed anatomically,and then the shoulder humerus rhythm is studied to get the motion trajectory of the shoulder.The number of degrees of freedom of the designed rehabilitation robot was determined according to the motion form and range of the upper limbs,and several training methods of the upper limbs were summarized to lay a foundation for the rehabilitation training in the future.From the aspects of structure,comfort,lightness,safety and control,the corresponding mechanism of the exoskeleton shoulder rehabilitation robot was studied.The designed rehabilitation robot has five degrees of freedom,including shoulder strap mechanism with two degrees of freedom and ball hinge mechanism with three degrees of freedom.The axes of the joints of the ball hinge mechanism are at a fixed point,corresponding to the glenohumeral joint of the human body.The shoulder strap mechanism drives the shoulder to move up/down and forward/backward,and the ball hinge mechanism drives the shoulder to move adduction/abduction,internal/external rotation and flexion/extension.The research solves the problem of the incoordination of man-machine instantaneous rotation center.At the same time,combined with ergonomics,in order to adapt to the rehabilitation needs of most patients,the shoulder height and shoulder width adjustment device is designed,and the driving system is studied and designed,so that it can be used as the power output to complete the rehabilitation exercise.The kinematics of rehabilitation robot is studied and analyzed.In order to facilitate calculation,the improved coordinate system was used to establish the D-H parameter table,and the relative pose matrix of each connecting rod was obtained according to the D-H parameter table.Then the forward kinematics formula of the rehabilitation robot was solved.By analyzing the closed solution and the numerical solution of the inverse kinematics method,this thesis selects the algebraic method of the closed solution to solve,and obtains the inverse kinematics formula of the rehabilitation robot.Finally,the correctness of the model is verified by Matlab simulation analysis.Based on the three-dimensional model of the rehabilitation robot,the experimental prototype of the rehabilitation robot was analyzed and assembled.Volunteers were selected for the experiment.First,the range of motion test was carried out.Volunteers were asked to touch their ears,drink water and other actions to determine the ultimate position and range of motion of the rehabilitation robot.The experiment of shoulder elevation motion was carried out to study and analyze the curve change trajectory of shoulder residual force and torque measured by sensor.The results show that the shoulder strap mechanism design is reasonable and the rehabilitation robot conforms to the kinematic cooperation.