空间稳像系统摆镜设计与仿真

Design and simulation of tilt mirror for space image stabilized system

摆镜作为稳像系统核心部件,摆镜单元的性能参数和外载荷对摆镜面形的影响为摆镜设计和装配的主要约束条件。在设计约束基础上,对摆镜及其装卡结构材料进行了选择,对结构进行了轻量化设计。为考察外载作用对摆镜面形影响规律,使用接触非线性有限元方法对摆镜组件进行了仿真,使用基于Zernike多项式的光机集成仿真方法消除刚体位移,得到了消除刚体位移后摆镜面形参数。仿真结果表明:外载作用下摆镜刚体位移明显;预紧力作用下刚体平移占据了刚体位移的主要方面;动力载荷作用下,当重力存在于光轴方向时,静力载荷对摆镜面形起主要作用,否则动力载荷对摆镜面形起主导作用。在仿真数据基础上,对摆镜零件进行了加工和装配,对装配后摆镜进行了面形测试,测试结果表明:摆镜面形能够满足设计要求,也说明了摆镜结构设计的合理性和仿真方法的有效性。

As the core part of space image stabilized system,the main constraint of design and assembly for tilt mirror is tilt mirror component′s performance parameter and the influence on mirror surface under the external load.According to the design constraint,the material of tilt mirror and fixing structure was selected and the lightweight design for tilt mirror and fixing structure was to be processed.In order to check the influence law of tilt mirror surface under external load,the assembly of tilt mirror was analyzed using contact nonlinear finite element method.The rigid displacement was eliminated by using opto-mechanical integrated simulation method based on Zernike polynomials and the surface parameter of tilt mirror after eliminating rigid displacement was gained.The simulation result demonstrates the rigid displacement obviously exists under the external load;piston term occupies the main aspects of the whole rigid displacement under the pretightening force;when the gravity is in the optical direction,the static load plays the dominating role on the surface change,otherwise the dynamic load plays the leading role under the dynamic load.On the basis of simulation,the tilt mirror parts were manufactured and assembled and the surface was also tested after assembling.The test result illustrates tilt mirror surface can satisfy the design requirement and also shows the rationality of the design of tilt mirror and validity of the simulation method.