Design Of Adaptive Backstepping Sliding Mode Control For Hybrid Conveyor Mechanism Based On Disturbance Observer

This paper mainly studies a hybrid conveyor mechanism which combines parallel mechanism and series mechanism.The conveyor mechanism has the advantages of large stiffness,strong bearing capacity,low cost and stable structure.The research and development of the hybrid mechanism mainly combines the advantages of series and parallel connection to make up for their respective shortcomings.Because the hybrid mechanism is usually a controlled object with multivariable,highly nonlinearity and coupling,Based on the advantages of parallel mechanism and series mechanism,the parallel mechanism has strong coupling among its branches.When the mechanism runs at high speed,its dynamic characteristics have a significant impact on the mechanism.The process of designing controller and Lyapunov function by inversion is very clear and has the characteristics of systematization and structuralization.Considering that sliding mode control has fast response and strong robustness to external disturbances and parameter changes,It is suitable for the control of hybrid mechanism.In order to ensure the robustness and stability of sliding mode control,the switching gain of sliding mode control is required to be larger than the upper bound of uncertainty.Usually,too high switching gain will cause chattering of sliding mode control.In order to solve the chattering problem and the problem that the upper bound is difficult to predict,an adaptive inverse sliding method combined with disturbance observer is proposed in this paper.Modular control algorithm.Firstly,the dynamic model of the hybrid conveying mechanism is solved and analyzed,and the established dynamic model is simulated by MATLAB to verify the reliability of the model.Considering the complexity of the dynamic model of the hybrid conveying mechanism,the dynamic model of the hybrid conveying mechanism is established.Inverse control algorithm is introduced to control the uncertainties in the system.However,when there are uncertainties such as friction,external random disturbance and modeling error,sliding mode control is robust to external disturbances and system parameter changes,so as to improve the control performance of the mechanism.To enhance the robustness of the system,this paper combines sliding mode control with inversion control to design an inversion sliding mode control algorithm.In order to ensure the robustness and stability of sliding mode control,the switching gain of sliding mode control is required to be larger than the upper bound of uncertainty.Usually,excessive switching gain will cause severe chattering.In order to solve the chattering problem and the difficulty of predicting the upper bound,an adaptive inverse sliding mode control with disturbance observer is proposed.Algorithm.The disturbance observer is introduced to weaken the chattering phenomenon of sliding mode control caused by too high switching gain,and the adaptive law is introduced to estimate the upper bound of unknown disturbances,so as to improve the trajectory tracking performance of the control system of the hybrid transmission mechanism.The simulation results of MATLAB show that the designed adaptive inverse sliding mode control algorithm combined with disturbance observer can improve the robustness and anti-jamming ability of the system,and effectively weaken the chattering phenomenon.Finally,according to the characteristics of the conveyor mechanism,a distributed control mode of "PC + UMAC" is adopted to complete the motion control experiment of the conveyor mechanism based on the experimental platform of the control system of the parallel conveyor mechanism.The adaptive inverse sliding mode control combined with the nonlinear disturbance observer.