Design And Simulation Of Servo Actuator-control Surfaces Of Aircraft Control System

Servo actuator is a vital part of modern aircraft control system,the rational design and good performance of the servo actuator is not only the basis of good flying qualities of the aircraft,but important measure of the aircraft control system design level and the level of aircraft design.This article establishes mathematical and simulation models of the servo actuator-control surface system,through simulation techniques to analyze the factors affecting the stability of the system,to shorten the design cycle of servo actuator as well as it will reduce the cost to test the sample,it has certain significance for engineering applications.According to the technical requirements of the design of an aircraft,the article select the form of aircraft power aided steering system,and design the servo actuator by deeply studying the works of servo actuator.And then the article studied the main performance parameters of static characteristics of the servo actuator.Combined servo actuator works,the article analyzed factors affecting static characteristics and proposed the corresponding improvement measures.By a certain type of servo actuator actual performance curve,the article analyzed the relationship between the performance parameters.Based on hydraulic transmission theory,the author simplified the physical model and built the basic mathematical model,the model with elasticity and clearance of support structure and the model which includes displacement feedback of support structure.These three models rang from simple to complex,and they work for the three different factors that will impact on the system respectively.then the article made the models linearized and worked out the corresponding transfer function.Based on the mathematical model has been established,the article select the simulation module on MATLAB / SIMULINK platform to construct the corresponding simulation models.To the characteristics of the servo actuator system,the article had detailed analysis.the article analyzed the speed and the flow characteristics of the spool valve,and studied the traceability of the servo actuator-control surface system,it also judged the stability of the servo actuator models that had established and analyzed the factors affecting the stability of the servo actuator,and then proposed to the method for improving.According to the model,this chapter worked out the Nyquist and Bode diagram of impedance characteristics and analyzed the factors affecting the impedance characteristics of the servo actuator and systems.Summarize the relationship between the static and dynamic characteristics of the servo actuator.Taking an aircraft for the study and understanding the design requirements of overall control system and the related specifications for aileron servo actuator design requirements,this chapter simplified the model of the servo actuator-aileron system and improved the nonlinear dynamical equation that established,and then simulated.The simulation results were compared with the test data and curves of the servo actuator,it showed the design was rational.While varying the relevant parameters of the system to simulate,the results show that parameters as the elastic modulus of oil,the refueling area of piston and the clearance of bearing has a certain influence on the stability of the system,it will provides important reference for the late test and optimization.