Research On Walking Aid Training Robot

Walking aid training robot is a kind of rehabilitation training equipment, which can assistpatients with motor dysfunction and elderly people to walk. It can control the motion of pelvisand coordinate with lower limbs’ gait while making hip or knee motion coordinate withnormal gait, thereby the self-balance of trainee can be acheived and the training goal can berealized. The study on walking aid training robot is significant to develop rehabilitationtraining technology and improve the life quality of patient and elderly people, meanwhile, it isalso in accordance with the requirements of the National long-term plan for science andtechnology development.Supported by the project “multi-functional walking aid rehabilitation robot”, which isone of the863key projects, this dissertation theoretically analyzes and simulates the structureof robot, the features of systematic mechanism and controlling strategies, manufactures theprototype, and experimentally studies the robot based on dSPACE semi-physical simulationplatform.A kind of walking aid training robot is put forward based on the review and analysis oftechnologies about lower limb rehabilitation training robot and pelvis motion control robotboth home and abroad. This robot includes series-parallel connection underactuated pelvismotion control mechanism and rope pull lower limb motion control mechanism, which canrealize the motion control of lower limb hip or knee and pelvis, and allow initiative movementof trainee that better fulfills the security requirements of training.For pelvis motion control mechanism a completely driven kinematics model isestablished, the operation trajectory planned and the accuracy of underactuated control outputanalyzed. Then the effect of mechanism inertia on drive performance is discussed, the drivingmoment of expected track planned and the effect of centring constraint spring stiffness andpretightening force on pelvis motion simulated. For lower limb control mechanism themapping relationship between rope motion speed/acceleration and hip or knee motionspeed/acceleration is analyzed by influence coefficient method, and rope motion output ofexpected track also planned by mechanism simulation. By using restraint method systematicforce spiral balance equation is established. Based on d’alembert’s principle system dynamicperformance is analyzed. And rope tension solution is acquired by generalized inverse algorithm. All the above provides basis for the choice of drive motor and the driveperformance test.Considering walking aid training robot is a multiple input multiple output nonlinearsystem, and has a strong coupling dynamic characteristics. In the analysis of robust trackingcontrol strategy is proposed based on the characteristics, a robust tracking control strategy toachieve walking aid training robot tracking control. Because walking aid training robot lowerlimb motor motion control system modeling is not accurate and external disturbances, thewalking aid training robot control system is considered for a class of uncertain linear systems,the system uncertainty hypothesis satisfies generalized matching condition, based on thedesign of robust tracking controller. The lower limb motion control mechanism track robusttracking control simulation, analysis of the accuracy of the control system, proved thefeasibility of robust tracking control strategy.According to the structural concept of walking aid training robot, the prototype ismanufactured. The upper computer of control system is dSPACE semi-physical simulationplatform, with which electric cylinder test and system calibration test are carried out on pelvismotion control mechanism, and system control test is analyzed in detail. A variety ofindividual tests and gait trajectory tracking test are carried out on lower limb motion controlmechanism after the confirmation of controller parameters. The test results indicate that theoverall performance of walking aid training robot can satisfy the requirements of practicaluse.