Design of frame-type support structure for space-based rectangular convex mirror tested on the back

Abstract

In view of the functional requirements of high reliability support and high stability support of rectangular convex mirror of space remote sensor, at the same time, considering the development cost and lead time, a frame-type support structure for rectangular mirror tested on the back of space remote sensor was designed, which included a support frame and two groups of flexible grooves. In-depth study was done about support principle and engineering realization of the space-based mirror support. The error sources of surface shape errors of space-based mirror assembly were summarized. Two groups of flexible structures were designed and their positions were reasonably arranged, so as to effectively eliminate or alleviate the surface shape errors caused by various error sources. The statics and dynamics simulation were carried out in view of the design result with the means of finite element analysis, then the test was carried out on the actual mirror subassembly. Experimental results show the surface shape error of mirror with the frame-type support structure is better thanλ/60(λ=632.8nm), the displacement of mirror is smaller than 0.008mm,the inclination angle is smaller than 1.5″. The mirror assembly has a reasonable distribution of modal, the fundamental frequency is 256 Hz, which is higher than the requirement of 120 Hz. Under the sin and random vibration, the acceleration amplification were 1.1 and 4.2 times respectively, and the dynamic stress under two test conditions were 14.5MPa and 128MPa respectively, The simulation and test results show that the support effect of the frame-type support structure is good, meets the high reliability and high stability support demand of rectangular convex mirror of space remote sensor.