Design and manufacturing of the central reflector sector of the «Millimetron» Space Observatory
Rocket and space engineering
1. Siberian State University of Science and Technology named after academician M.F. Reshetnev, 31, Krasnoyarsky Rabochy av., Krasnoyarsk, 660014, Russia
2. Compani «Information satellite systems of academician M.F. Reshetnev», 52, Lenin str., Zheleznogorsk, Krasnoyarsk region, 662972, Russia
«Millimetron» Space Observatory with the space telescope 10 meters in diameter is meant for study objects in the Universe at millimeter and infrared wavelengths .
The study of space telescopes analogues all over the world gave the following variants of mirror design:
— waffle structure with ribs in the form of a combination of triangular and pentagonal elements (ASC LPI them. Lebedev RAS) ;
— sandwich made of composite material with triangular ribs (Planck telescope) ;
— silicon carbide waffle structure with ribs in the form of triangular elements (Herschel Telescope) .
This paper considers design and manufacturing of the mirror based on composite materials. The main problem of implementing composite materials for highly-stable sizes design consists of synthesis of the material, its qualitative and quantitative composition, as well as reinforcement structures to ensure minimum thermal deformations at a certain level of stiffness and strength characteristics .
Thus, one of the objectives of this work lies in selection of optimal composite material reinforcement structure of reflecting surface. All calculations were carried out using finite element method.
Another problem of this work lies in selection of central mirror optimal ribbing structure. We considered various variants of the central mirror design, and carried out modal and static analysis for each variant. From this analysis, we selected the central mirror design, satisfying the specified requirements.
Further, we carried out product design and production engineering solutions for central mirror manufacturing. As a result, we selected central mirror sector-manufacturing technology that combines thermal compression and vacuum autoclave molding using a unique equipment. A feature of this technology lies in the fact that sector shaping is performed in one technological cycle. Raw stocks of all materials for all sector elements (reflecting surfaces, ribs, edges) laying out is carried out in in the raw state. Reinforcement ribs necessary shape are formed by an utility unit. The adhesive is not used in the design.
We made tests of this technology with the pattern corresponding to the accepted engineering solutions for the central mirror. The results of the pattern manufacturing confirmed the efficiency of the chosen technology. Thermal vacuum tests confirmed stability of the pattern geometry.
Keywords:composite material, wafer construction, rubber punch, vacuum-autoclave molding
- Sintez mekhanizmov orientatsii kosmicheskogo teleskopa «Millimetron». 1. Vozmozhnosti mekhanizmov parallel’noi struktury dlya orientatsii kosmicheskogo teleskopa «Millimetron», URL: http://technomag.edu.ru/doc/534292.html (accessed 01.01.2013).
- FIANE razrabotany pretsizionnye paneli dlya observatorii «Millimetron», URL: http://www.fian-inform.ru/astrofizika/item/90-v-fiane-razrabotany-pretsizionnye-paneli-dlya-observatorii-millimetron (accessed 12.02.2013).
- Metody i sredstva stabilizatsii opticheskikh parametrov krioteleskopov kosmicheskogo bazirovaniya i nazemnykh imitatsionno-ispytatel’nykh kompleksov, URL: http://tekhnosfera.com/metody-i-sredstva-stabilizatsii-opticheskih-parametrov-krioteleskopov-kosmicheskogo-bazirovaniya-i-nazemnyh-immitatsionno-ispitatilnih-kompleksov (accessed 06. 10. 2004).
- Teleskop Gershel’ — proryv v novuyu real’nost’, URL: http://www.astronet.ru/db/msg/1233419 (accessed 20.02.2009).
- Gardymov G.P., Meshkov E.V. Kompozitsionnye materialy v raketno-kosmicheskom apparatostroenii (Composite materials in the aerospace instrument making), Saint Petersburg, SpetsLit, 1999, 271 p.