Structure Design And Trajetory Planning Of The Center-driven Robot For Upper Limb Rehabilitation

According to statistics,the number of stroke patients over the age of 40 has reached 10.36 million in china,and the numbers are still increasing by 1.5 million each year.In many sequelae produced by stroke,the highest incidence is hemiplegic,of which 85% associated with upper limb dysfunction.Medical theory and clinical evidence show that the scientific rehabilitation training is a very important treatment of upper limb functional recovery for the stroke patients besides surgery,drugs and electrical stimulation.With the combination of medicine and engineering,by using robots to help the stroke patients to complete the rehabilitation of the upper limb function become an inevitable trend.Based on the research of domestic and international,and combined with the Shanghai Science and Technology Support Project "The key technology research in stroke patients with the intelligent interactive robot for upper limb rehabilitation",the paper proposed a novel center-driven upper limb rehabilitation robot and studied its kinematics and trajectory planning by analyzing shortcomings and deficiencies of the current upper limb rehabilitation robots.Firstly,the new center-driven transmission system of the robot was studied.For decreasing the volume of the robot arm and the influence of motor noise,radiation and other adverse factor on patient,the paper raised a center-driven power transmission structure.The structure design of the power system placed on the base of the robot and the power generated by the motors parallel output by the gears was completed the aim of center-driven power system,center-driven 3-DOF transmission system and rotation mechanism for left/right upper limb training.Through mechanical design and strength check,the prototype of the center-driven upper limb rehabilitation robot has been accomplished.Based on the structure design,the kinematics of the center-driven robot for upper limb rehabilitation by the D-H parameters method was analyzed and the Forward and inverse kinematics equations and the Jacobian matrix was deduced.Forward and inverse kinematics equations represented the relationship between the joint movement angles with the situation and attitude of the robot handle.And the Jacobian matrix represented the speed relationship between each joint with the robot handle.Then,the trajectory planning for rehabilitation was accomplished.By comparing the advantages and disadvantages of joint space describe and cartesian space describe,and taking into account the structural features of the center-driven robot for upper limb rehabilitation,the paper choose a cubic polynomial trajectory planning method in the joint space describe to achieve the robot trajectory planning.For the passive upper limb rehabilitation training,this paper accomplished the trajectory planning of the movement of refers to the nose and painting diamond.Finally,the experiments which were single degree of freedom motion control experiment,left and right individual training experiments and multi-DOF trajectory control experiments were taken on the prototype of the center-driven upper limb rehabilitation robot.The experimental results shows that the structure design of the center-driven robot for upper limb rehabilitation can achieve upper limb 3-DOF rehabilitation movement.