Research On Active Disturbance Rejection Control Technology Of A Guided Rocket Servo System

During the guided artillery rocket flight,many uncertain factors are existing.These random interference factors have an important influence on the guided artillery rocket's motion,stability and final hit accuracy.Specifically,the electromechanical actuator(EMA)of the guided artillery rocket is a complex nonlinear system,including various disturbances such as mechanical clearance,friction,gust disturbance,etc.Therefore,how to overcome these nonlinear disturbances and improve the reliability of the EMA's control has Important practical significance.In this paper,a kind of guided artillery rocket's EMA was taken as the research object,and an active disturbance rejection controller(ADRC)was proposed to suppress the disturbance by estimating the disturbance and eliminating it in real time.The main contents are as follows:Firstly,the overall design of the EMA was completed,including transmission scheme design,motor selection,and structural design.A mathematical model of the EMA was established based on the designed mechanical structure.Secondly,the active disturbance rejection controller(ADRC)based on the EMA were designed.On the basis of this,only the friction torque and the hinge load moment were considered(without considering the mechanical clearance).the disturbance rejection performance of the ADRC,PID controller,fuzzy adaptive PID controller(Fuzzy-PID)and BP neural network parameter adaptive PID controller(BP-PID)were compared and analyzed from the time domain and the frequency domain respectively.The simulation results showed that ADRC has greater immunity to disturbance.Thirdly,the influence of the mechanical clearance on the ADRC was discussed.Theinfluence of the same load condition and different mechanical clearance on the ADRC was analyzed by simulation.It was found that the Mechanical clearance is easy to cause the oscillation of ADRC,and with larger of the mechanical clearance,the oscillation frequency will be lower and the the amplitude of the oscillation will be larger.In addition,the performance of the ADRC under the same mechanical clearance condition and different load conditions was analyzed by simulation and experiment.The results showed that under the same mechanical clearance condition,with larger of the load,the disturbance range of the ADRC or LADRC will be larger.Furthermore,the effects of friction and nonlinear loads on the ADRC are also analyzed.The simulation results showed that ADRC has complete compensation ability for friction and nonlinear loads within a certain range,indicating that ADRC is robust to the above two nonlinear factors.Finally,the semi-physical simulation platform of the EMA's system was built,including the mechanical structure and the hardware circuit of the EMA,etc.and the feasibility of the simulation platform was verified by the semi-physical simulation experiment.