Research On Sliding Mode Control Method Of Lower Extremity Exoskeleton Robot

Lower extremity exoskeleton robots are the frontier research technologies in the fields of artificial intelligence,robotics and Bionics in recent years.Lower extremity exoskeleton,as a wearable device,is closely related to human motion and achieves human-machine coupling.The key to achieve human-machine coupling lies in the research of lower extremity exoskeleton control algorithm.A stable and efficient control algorithm can achieve accurate control of lower extremity exoskeleton robot in complex external environment.This topic mainly carries out mechanical modeling for the lower extremity exoskeleton robot,designs and implements the sliding mode control algorithm,and improves the overall structure of the control system,making the lower extremity exoskeleton robot have excellent motion control characteristicsThis paper first summarizes the research status of lower extremity exoskeleton robots at home and abroad,establishes a three-link model of lower extremity exoskeleton robots,establishes the system dynamic model of lower extremity exoskeleton robots by D-H method analysis,Lagrange dynamic analysis,and models and analyses the electrical drive system of the exoskeleton robots,and obtains the system control model.The sliding mode control method of the lower extremity exoskeleton robot is mainly studied,and the overall structure of the exoskeleton control system is analyzed.On the basis of the traditional position control algorithm,gravity compensation is designed to improve the controller to form a position control with gravity compensation.The equivalent sliding mode control algorithm is designed,and the symbolic function is replaced by the design of saturation function and equivalent to each other.Items and switching items are designed to enhance the anti-disturbance ability and response speed of the controller.Further,approximation law switching fuzzy adaptive sliding mode control is designed to change the approximation speed of the system by the approximation law,improve the control performance of the system by the fuzzy system,and solve the chattering problem of sliding mode control.Through the way of joint simulation of MATLAB and Adams,different control methods are compared and analyzed to verify the feasibility of the control method.Finally,the hardware platform of the control system is designed,the dual-core controller design is used,the hardware flow and software program implementation are designed,and a one-legged test platform is established.The control method designed is tested,the stability and feasibility of the control method are verified,and the good control effect of the approach law switch fuzzy adaptive sliding mode control is verified.