Research On Control Strategy Of Integrated Parallel Robot For Fracture Reduction And Rehabilitation

In view of the clinical needs of fracture treatment for precision reduction surgery and compliance rehabilitation training,this thesis takes the integrated parallel robot for fracture reduction and rehabilitation(the integrated robot)as the research object,carries out the research of control system and control strategy.The research content mainly includes the software and hardware design method,trajectory control strategy and compliance control strategy of the control system.The contribution of this thesis mainly includes:1.Software-hardware design of the integrated robot control system.This thesis applys distributed control method to improve the flexibility of system,designs the hardware circuit and embedded program.At the same time,this thesis carries out the multi axis synchronous trajectory planning,builds the force acquisition system and the hardware platform.In view of the needs of robot control system for fracture reduction surgery and rehabilitation training,the functional modules are divided,the bottom communication frame of the software is designed,the integrated robot control interface based on QT outline is designed.At least but not last,this thesis accomplishes the design of the control system software.2.Trajectory control strategy of the integrated robot.In view of the high-precision control requirements of fracture reduction surgery,this thesis builds the Simscape simulation model of the integrated robot and its controller.By comparing the characteristics of incremental PID control algorithm,fuzzy control algorithm and sliding mode control algorithm,a trajectory control strategy of PID position and sliding mode speed controller is proposed.Simulation experiments are carried out to verify whether the proposed controller meets the control requirements of the robot for reset surgery.The above control algorithm is embedded into the hardware platform for trajectory tracking experiment.The maximum position error of the trajectory is0.021 mm,which shows that the trajectory control strategy has high control accuracy and can fulfil accurate and efficient fracture reduction surgery.3.Compliance control strategy of the integrated robot.In view of the compliance safety control requirements of fracture active and passive rehabilitation,the secondorder spring-mass-damping model of each branch chain is established,and the admittance controller based on joint space is designed to make the robot output compliance action.This thesis analyses the influence of control parameters on system response deeply,and the passive and active rehabilitation simulation analysis is carried out to verify the effectiveness of the admittance controller.The admittance control method based on joint space is embedded into the robot hardware platform,and the teaching and dragging experiment of passive rehabilitation is designed.The robot moves with the force at the end,and stands still in the current position and posture after withdrawing the force.The force compliant motion control experiment of active rehabilitation is designed.The robot moves in the force direction.After the force is removed,the robot goes back to the original position and pose,and the end pose error of moving platform is 0.084 mm approximately.According to the experimental results,the mobility controller based on joint space can complete the compliant and safe rehabilitation control.In this thesis,the software-hardware design of the integrated robot for fracture reduction and rehabilitation control system is carried out,which realizes the accurate trajectory control for fracture reduction surgery and the compliant safety control for fracture rehabilitation treatment,improves the intelligent level of fracture treatment,and lays a technical foundation for the integration of high-efficiency,high-precision and high-safety robot system.