Research On Disturbance Rejection For Servo System Of Industrial Robot Joint Based On Extended State Observer

Industrial robots are widely used in the automotive,mechanical,chemical,electronic and electrical and food industries.Industrial robots are the basic equipment for intelligent manufacturing.The joint servo system is the basic control unit of industrial robots,which directly affects the performance of industrial robots.The traditional PID control has poor anti-disturbance performance and often cannot meet the high-performance control require ments.Most control strategy d epends on the accurate mathematical model of the system,but the actual servo system with parameter change and disturbance and other uncertainties.It is difficult to establish accurate mathematical model.Therefore,research on anti-disturbance control strategies of joint servo systems that do not rely on accurate mathematical models,which improve system control accuracy and dynamic performance.It is helpful to the development of industrial robot technology.In view of the time-varying load,parameter and model uncertainty of joint servo system,an adaptive robust sliding mode control strategy based on linearly expanded state observer is proposed.Through simulation analysis and experiments,the control performance of the joint servo system under this control strategy is studied.The main work of this article is as follows:(1)Taking the single joint servo system of industrial robot as the research object,according to its kinematic and dynamic equations,the joint load characteristics are analyzed,and then the system load model is established.Through the frequency domain analysis of the model,the approximate second-order state equation and the third-order expanded state equation of the joint servo system are obtained.(2)The system expansion state equation is used to realize the linear expansion state observer algorithm,which estimates and compensates for system disturbances.Adaptive law is used to estimate inertia and variable sliding channel gain(b)control strategy is designed in combination with robust sliding mode control.In Matlab/Simulink,the three-loop control simulation model of joint servo system is established,and the simulation research of control strategies is carried out to analyze their control performance.The simulation results show that the designed control strategy has better control performance.(3)Based on the hardware environment of DSP-TMS320F28335 chip,the program is written and debugged in CCS6.0 software environment to realize the relevant control strategies algorithm.(4)The experimental platform is built to simulate the joint load output.The control strategy is studied through the experimental platform.The experimental results show that the designed control strategy can effectively compensate the system disturbance and improve the control accuracy and dynamic performance of the joint servo system.