遥感相机次镜组件等效模型的研究

试验模态分析在航空航天领域结构力学的研究中得到广泛的应用，而且起到相当重要的作用。文章探讨了较易破损或是比较昂贵结构的试验模态分析方法－等效模型法。该方法是基于理论和结构灵敏度分析，研究原型与等效模型材料不同时的等效模型研制方法。这一方法被应用于某遥感相机的次镜组件的模态试验分析，得到了较好的结果。

A Study on the Equivalent Model of Second Reflect Mirror Unit of a Remote Sensing Camera

Modal test analysis is widely used in the structural mechanism studies in the aerospace field and plays a very important role.A method to carry out modal test for vulnerable or precious structure is studied in this paper.This method is named equivalent model method.Modal test can be simplified with the development of the equivalent model.In order to make the equivalent model is equivalent to its prototype,it is necessary to keep the geometrical and stiffness equivalent.The geometrical equivalent is satisfied through the UNIGRAPHIC software at first,the mass of the test model is equal to the prototype.Based on the basic plate theory and structural sensitivity analysis,this paper discussed the theory of equivalent model whose structural material is different from the prototype.This can make sure that the stiffness of test model is equivalent to its prototype.In order to verify this theory,it is applied to the second reflect mirror unit of a remote sensing camera.Through analysis,any frequency and modal shape of the test model of the second reflect mirror unit is equal to its prototype.So if this method is used in the similar condition,satisfactory result can be obtained.This method can be used as a solution to simplify the modal test of aerospace equipment.