The Trajectory Planning And Optimization Of Five Degree Of Freedom Upper-Limb Rehabilitation Robot

With the development of modern rehabilitation medicine,it has been an attractive research focus on applying the robotics-aided training system in nerve centers rehabilitation.This research project is about a 5-DOF upper limb rehabilitation robot,which adapts human arm movement.It can drive patients to have rehabilitation training in order to restore the upper limb with movement disorder.In order to simulate the movement law of the patients'arms when the rehabilitation physicians treat patients,the thesis uses 7-order polynomial B-spline interpolation methods to have trajectory planning of upper limb rehabilitation robot,and based on the above,the trajectory of upper limb rehabilitation is optimized according to trajectory smoothness indicator,energy consumption indicator and human movement complexity Fitts indicator.The main contents of this thesis are as follows:(1)Establishing the kinematics and dynamic model of rehabilitation robot.Firstly,it makes a more in-depth analysis and research on the movement system of the five degree of freedom upper limb rehabilitation robot,and establishes coordinate transformation matrix with DH,calculating the formula for solving the forward and inverse solutions of the kinematic equations.Secondly,it establishes the dynamic model of rehabilitation robot with Lagrange and analyzes the dynamics of the robotic arm during the operation.Finally,it makes a simulation on the kinematics and dynamics model.(2)In order to improve the similarity between the trajectory and the patient upper limb movement,and to guarantee the realization of the trajectory in the robot hardware platform,it is necessary to carry out interpolation of the teaching points.For the trajectory planning of upper limb rehabilitation robot in Cartesian space,the single joint movement is interpolated by using linear&circular.The multi joint movement is interpolated by using three B-spline curve.(3)For the 5-DOF rehabilitation robot,it establishes the mapping relationship between the trajectory of a given discrete point set and polynomial function with 7 order B-spline polynomial interpolation method.On the basis of giving the speed,acceleration and jerk in the starting position and ending position,it obtains the 7-order polynomial expression of the trajectory of a discrete point set,ensuring the trajectory of the curve sexual and smooth.(4)On the basis of considering position,velocity,acceleration and jerk of rehabilitation training and further combined with smooth trajectory index,energy consumption index,human motion complexity Fitts index and other indices,the upper limb motion trajectory planning problem is transformed into a nonlinear multi-objective optimization problem.Finally,genetic algorithms is adopted to optimize the design of the training trajectory of the 5-DOF upper limb rehabilitation robot.The simulation results show that considering all the constrains and indicators,the derived trajectory is in keeping with teaching acts,and the change in velocity is similar to motion characteristics of human body.The derived trajectory can meet the requirement of rehabilitation medicine.