Researches On Transfer Model Of Micro-Vibration In Spacecraft Platform

Micro-vibration is an important factor of influencing some critical performance of high-accuracy spacecraft such as pointing accuracy and imaging quality.In order to revise the imaging quality and improve the accuracy of attitude control,the response at some payloads such as cameras caused by micro-vibration must be obtained.However,sensors can not be installed at the target points to measure the response data directly because cameras are often installed at some special position.So,three methods of constructing the micro-vibration transfer model are proposed in this paper.Based on the micro-vibration transfer model,the response of the unknown target position can be calculated accurately and quickly using the signal of disturbance source or the response of measuring point.The contents of this paper are as follows:A kind of disturbance source transfer model is constructed under the modal coordinate including the disturbance source transfer model based on modal cost analysis,the disturbance source transfer model based on modal energy flow,the disturbance source transfer model based on modal DC gain.These models can be used to calculate the response of the target position when knowing the signal of micro-vibration source.The simulation experiment on the solar panel shows that the error of the maximum peak value of displacement response obtained from the disturbance source transfer model is 1.53%,the error of the maximum peak value of acceleration response is less than 2.1%.A kind of disturbance source transfer model is constructed under the physic coordinate in this paper,which bases on the Second Order Balanced Truncation(SOBT).This model uses the Low Rank ADI algorithm to solve the high dimension Lyapunov equations,which solves the difficult problem of solving high dimension Lyapunov equations.The simulation experiment on the solar panel shows that the error of the maximum peak value of displacement response obtained from the disturbance source transfer model is 1.53%,the error of the maximum peak value of acceleration response is less than 2.1%.A kind of micro-vibration response mapping model is constructed to get the response when the signal of micro-vibration disturbance source is unknown,and some basic principles to select the measuring point are proposed.The simulation experiment on the solar panel shows that the error of the maximum peak value of displacement response obtained from the response mapping model is 0.98%,the error of the maximum peak value of acceleration response is less than 1.27%.A real satellite platform is used in the simulation experiment to verify the three methods of constructing micro-vibration transfer model in this paper.The errors of the maximum peak value of displacement response obtained from the three methods are less than 1%,the errors of the maximum peak value of acceleration response are less than 8%.The three kinds of micro-vibration transfer model constructed in this paper can get high accuracy with small calculation,which lays the foudation of indirect measuring and eliminating the influence of micro-vibration on cameras.