The Platform Construction And Joint Control Algorithm Research For The Lower Extremity Exoskeleton Robot

The lower extremity exoskeleton robot system is a system which needs a very well control performance.In this thesis,we try to design a simple,stable and high performance controller by using the periodicity of lower limb motion.By using this controller,the control performance of the robot be improved,and the learning ability of the control algorithm improve system's robustness greatly.On the basis of the existing research,the lower limb movement is a typical periodic behavior through the analysis of the mechanism of the human lower limb movement.Later,the lower limb movement of the human body is mainly provided by the lower limb muscle power,and the form and content of the lower limb external skeleton robot were expounded by Hill model.On this basis,the main power forms of the lower limb external skeletal robot were analyzed,and this provides a theoretical basis for the design of the power assisted lower extremity external skeletal robot system.According to the characteristics of the lower limb's motion,the two joint position track controller with periodic learning ability is designed.The first controller is composed of an improved iterative learning control algorithm,and It improves the robustness of the system by adding a forgetting factor to the closed loop PD type iterative learning control algorithm.In addition,it not only has the advantages of superior control effect,but also has the characteristics of simple structure,easy programming,high stability and so on.But it is suitable to be used in the rehabilitation of lower limb skeletal robot system because of its own algorithm structure need a higher requirements for the lower limb trajectory.Another controller uses the RBF neural network controller and PID controller to control the joint structure of the lower limbs of the machine.At the beginning of the control,the PID controller meet the dynamic performance of the system,and the RBF neural network control system improve the steady-state performance of the system.Finally,the high performance of the system is realized.Finally,according to the power assisted analysis of the robot system of the lower limb,the trajectory control scheme of the joint position of the lower limb based on gravity support was determined.And the joint control platform of the robot system of lower limb is built.The control platform uses the embedded computer as the processor,sensing the current joint position track through the human lower limb posture sensor.And the attitude sensor and the mechanical legs constitute a closed-loop position control system.The position control of the joint is calculated by position deviation and control algorithm in the embedded computer environment,And the position control amount of write drive through the serial port.Final drive motor of lower limb motor...