Design And Implementation Of High Frequency Motion Simulation System

The high frequency motion simulation(HFMS)is a high-frequency angular position servo system,whose core device is a six-degree-of-freedom parallel mechanism(Stewart platform).It is necessary to deeply analyze and study the Stewart platform system characteristics,the preprocessing and solution of high frequency command,and high frequency response servo system design.The background of this paper is the aerodynamic servo elastic motion of the aircraft.In-depth analysis of the dynamic characteristics of the Stewart platform is needed,and the design of high frequency response control system design and research on application problems of simulation test is studied.Firstly,the dynamics of the Stewart platform is modeled based on the Newton-Euler method,and the load time-varying characteristics of each link channel are analyzed.According to the working principle of linear motor,the linear model is established,and the saturated nonlinear factors under high frequency conditions are considered to improve the controlled object model.The background of the project is that the Stewart platform is placed on the inner frame of the three-axis simulation turntable to form a composite motion simulation.Therefore,it is necessary to analyze the disturbance factor of the output force of the linear motor under the moving base.Secondly,the wavelet packet transform method is applied to study the optimal decomposition reconstruction signal processing method,aiming to realize the frequency division processing of high frequency vibration signals.By analyzing the forward and inverse kinematics of the Stewart platform,the solution method of pose command is studied and the research on pose inverse optimization algorithm is carried out,based on inertial space fixed point.Thirdly,based on the saturation nonlinear characteristics and time-varying characteristics of linear motors,an adaptive control method based on Lyapunov stability theory is studied,and the model reference adaptive control method is applied to the second-order system.By comparing the simulation tests,the effect of control parameters on system performance can be obtained.Finally,the instruction preprocessing algorithm and the solution algorithm are used to process the high frequency angular rate command signal output by the inertial unit.Based on the model reference adaptive compensation control method,the high frequency ring position controller of each link channel is designed and verified by simulation test.The real-time operating mechanism of the software and the typical module flow are analyzed,and the human-computer interaction interface is designed.