Design And Performance Analysis Of Portable Hybrid Wrist Joint Rehabilitation Mechanism

Wrist joint plays an irreplaceable role in daily life,and the wrist will be damaged in each scene,which will greatly affect the quality of life of the patient.Therefore,it is necessary to study the wrist joint rehabilitation institutions,which can provide good rehabilitation training for patients with wrist joint injuries.In this paper,a(3-UPS/PRR)&R portable hybrid wrist joint rehabilitation mechanism is designed according to the human wrist joint anatomy and wrist joint motion characteristics,it can meet the training of wrist joint palm flexion/back extension,adduction/abduction,and pronation/pronation.This mechanism has two types of end actuators and rotating center adjustment devices to meet the rehabilitation of patients with different needs and achieve human-machine integration.This paper analyzes the motion of the portable hybrid wrist joint recovery mechanism.The main mechanism of the rehabilitation mechanism,3-UPS/PRR,is analyzed by using the screw theory,In this paper,we find that there are four degrees of freedom of rotation on the X-axes,Y-axes,Z-axes and Z-axes.Verify the calculated degrees of freedom according to the modified G-K formula.On this basis,the inverse position solution of the mechanism is performed using Euler angle transformation method and closed vector method,and the forward position solution of the mechanism is verified using particle swarm optimization(PSO)method.The solution of the workspace of a 3-UPS/PRR parallel mechanism with constraint conditions shows that the workspace of the mechanism is internally continuous and has no singular configuration.The results show that the mechanism has good kinematic characteristics.The first order influence coefficient matrix of the mechanism,also known as the velocity Jacobian matrix,is obtained by deriving the inverse position solution expression from time.The second order influence matrix is obtained by deriving from time,which verifies the feasibility of the mechanism.Using Solid Works and Adams,this paper builds a virtual prototype of the mechanism,and performs the reverse kinematics and forward kinematics simulation.Finally,the movement of the mechanism is simulated,including the bending and stretching of the hand,the adduction and the extension,the inner rotation and the outer rotation.The results show that the rotational angle of the moving platform is in the normal range of human activity.Moreover,the extension and contraction of the branch chain are consistent with human activities,and the curves are smooth and continuous,with no abrupt changes.Based on the inverse kinematics simulation curve,the forward and reverse kinematics results of the mechanism in motion are identical.Which proves that the simulation of forward and reverse kinematics is correct.The man-machine integration system is established through Anybody software,and the analysis shows that the force and muscle expansion of the damaged muscles during the process of driving the wrist joint of the human body to perform palm flexion,back extension,adduction,and abduction training are within the normal range,and the muscle activity is within the maximum intensity,indicating that the rehabilitation training worn by the rehabilitation institution on the human body conforms to the laws of human kinematics,and can fully conduct rehabilitation training for the damaged muscles,Muscles do not suffer secondary injury,providing effective theoretical support for accurate evaluation of rehabilitation effects.