Research On Control Strategy Of Rudder Surface Load Simulation System

The rudder load simulation system is a semi-physical simulation test equipment for the aircraft servo control mechanism under ground conditions.It is mainly used to reproduce various aerodynamic loads to achieve the detection of the servo control mechanism to ensure the accuracy of flight control.Therefore,the accuracy of the aerodynamic load spectrum will directly affect the credibility and reliability of the servo control mechanism detection results,and will ultimately affect the aircraft’s flight control performance.However,the rudder load simulation system is a typical passive loading system,which will be interfered by excess torque and other factors.Relying on the air rudder surface load simulation system project of the Aerospace Institute,the thesis takes the rudder load simulation system as the research object.In order to improve the dynamic tracking accuracy of the system load spectrum,a composite control strategy based on neural network is proposed.And it is analyzed and verified by the simulation and experiment.Firstly,the structure and working principle of the rudder load simulation system are introduced,and the mathematical model of the rudder load simulation system is established,which is the basis of the theoretical analysis of the following system.This thesis analyzes the dynamic characteristics of the system under the conditions of no disturbance and disturbance,studies the influence of different structural parameters on the system performance,and gives reasonable suggestions on structural design.Secondly,the operation state of the rudder system in different working stages is analyzed,and the mechanism of the surplus torque of the system is revealed.This thesis studies the characteristics of the excess torque of the system,and explores the influencing factors of the excess torque,which lays a theoretical foundation for the elimination of the excess torque.Thirdly,aiming at the problem of improving the dynamic loading accuracy of the system,the corresponding algorithm derivation and controller design of PID control,compound control based on feedforward compensation and compound control based on neural network are carried out respectively.Then,the simulation experiments are carried out by using Matlab / Simulink,including redundant torque suppression and different load spectrum under the interference of redundant torque.The simulation results are compared and the control effects of different control strategies are analyzed.Finally,according to the task requirements of the project,the related design of the load system in the project is given.On the basis of this design,the experimental loading verification system is built,the measurement and control software program is written,the redundant torque suppression experiment and the dynamic loading experiment under the interference of redundant torque are carried out,the effectiveness of the control strategy proposed in this thesis is verified,and the control effect is compared with PID control strategy and compound control strategy based on feedforward compensation.