Font Size: a A A

Study On Dynamic Parameter Identification And Control Method Of Upper Limb Rehabilitation Robot

Posted on:2021-02-01Degree:MasterType:Thesis
Country:ChinaCandidate:J L WangFull Text:PDF
GTID:2428330623483775Subject:Control engineering
Abstract/Summary:PDF Full Text Request
With the development of modern rehabilitation medicine,using robots to assist stroke patients in rehabilitation training for limbs has become one of the hot topics all over the world.The upper limb rehabilitation robot targeted at stroke patients is a robot system that assists rehabilitation physicians in rehabilitation training.It has significant deference with traditional robots.Firstly,during the rehabilitation training it's necessary to consider about safety of patients,validity of recovery and acceptance to the robots of patients.Secondly,the human bodies structure mechanism and the knowledge of robotics,Rehabilitation Therapeutics,etc.,must be taken into account in terms of its design.This thesis tried to sort out the problems of inaccuracy in the establishment of upper limbs healthy recovery robot models,of uncertainty disturbance during rehabilitation training and of the safety of patients in rehabilitation training.We have built a mathematical model of upper limb rehabilitation robot,obtaining its accurate kinetic equation by using particle swarm optimization(PSO)and then have limited the uncertain disturbance of robots in rehabilitation training by using the fuzzy compensated algorithm.At the end we have used impedance control algorithm to support patients the effective protection in rehabilitation training.The main work of the thesis could be summarized as follows:(1)Explain how to build the mathematical model of upper limbs healthy recovery robot system.At first we analyzed the body structure and the actual situation of patients and built 3D modeling of the robot by software Proe.Then based on the change of homogeneous coordinates in space of robot's joints and links we built a kinematics model by D-H(Donative-Hartenberg).Finally the kinematics model of upper limb rehabilitation robot was built via Lagrange equation and the controlling moments of each joints of robots' kinematics model were obtained through experiment of Matlab.(2)Identify parameters of the kinematics model of upper limbs healthy recovery robot system.In rehabilitation training,arms of patients put an extra load on upper limb health recovery robot,which often made it hard to establish an accurate kinetic model of upper limb health recovery robot,so we presented PSO to identify the parameters of the robot's kinetic model.Through Matlab we have conducted a simulation experiment on upper limbs healthy recovery robot's kinematics model for identification of parameters,comparing its identification effect with that of traditional method of least squares.The simulation experiment turned out that,compared to method of least squares,the identification result of the kinematics model of upper limbs healthy recovery robot system by particle swarm optimization was more accurate and this algorithm can effectively reduce the margin of error in tracking controlling of robots in rehabilitation training.(3)Explain how to control sliding mode of upper limb rehabilitation robot based on fuzzy compensation.While there has been spasm and disturbance of patients and some of outside uncertain disturbance in rehabilitation training,we presented,based on the accurate mathematical model of upper limb rehabilitation robot,a sliding mode control algorithm according to fuzzy compensation would be able to be used in the tracking control process of rehabilitation training trajectory.Firstly,we designed a sliding mode controller,introduced fuzzy compensation links into it,and added fuzzy compensation to counteract the uncertainty interference caused by environment and patients to upper limb rehabilitation robot system.Then,via Lyapunov stability theory the stability of the control law in detail would be proved.Finally,through simulation experiment of Matlab,compared with proportional-derivative control,the simulation experiment results also showed that sliding mode control based on fuzzy compensation could ensure the tracking accuracy of robots while overcoming the sudden disturbance of patients during the rehabilitation training.(4)Explain the impedance control of upper limbs healthy recovery robot.For the sudden stiffness of patients' limbs during the rehabilitation training,an impedance control algorithm has been proposed.The algorithm was applied to the tracking control of the rehabilitation training trajectory of the upper limb rehabilitation robot.First,we designed an impedance controller,which calculated the relationship between the relative position between the patient and the rehabilitation robot and the interaction force to achieve compliance in the control process.Then,by using Lyapunov stability theory we carried out a detailed convergence analysis of the algorithm.Finally,Matlab simulation experiment showed that the control algorithm could ensure that the upper limb health recovery robot has a certain tracking accuracy during the training,and can also effectively protect the patient from rigid limb by obeying its directions.
Keywords/Search Tags:upper limb rehabilitation robot, stroke, variable parameter particle swarm optimization, fuzzy compensation, impedance control
PDF Full Text Request
Related items