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Large deployable mesh reflectors are crucial in space applications due to their lightweight and efficient storage characteristics. However, achieving high surface accuracy and managing the significant thermal effects experienced during on-orbit operations remain challenges in deployable mesh reflector design. This paper presents an innovative dynamic thermal modeling methodology for large deployable mesh reflectors, effectively addressing these obstacles. The proposed method considers a comprehensive set of radiation factors including solar, Earth, Albedo, and reflector emissions. This allows for a detailed analysis of dynamic thermal behavior of the reflector, thereby accurately capturing the impact of thermal strains of cable members on surface accuracy. Simulations of a 101-node center-feed parabolic reflecting surface of a deployable mesh reflector indicate that the proposed method can reveal non-uniform temperature distributions, unlike traditional methods that presuppose uniformity. Additionally, the proposed method has proven effective in accurately predicting the root-mean-square error increase of the reflector, typically unobserved in traditional thermal modeling techniques.
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Review of Root-Mean-Square Error Calculation Methods for Large Deployable Mesh Reflectors
In the design of a large deployable mesh reflector, high surface accuracy is one of ultimate goals since it directly determines overall performance of the reflector. Therefore, evaluation of surface accuracy is needed in many cases of design and analysis of large deployable mesh reflectors. The surface accuracy is usually specified as root-mean-square error, which measures deviation of a mesh geometry from a desired working surface. In this paper, methods of root-mean-square error calculation for large deployable mesh reflectors are reviewed. Concept of reflector gain, which describes reflector performance, and its relationship with the root-mean-square error is presented. Approaches to prediction or estimation of root-mean-square error in preliminary design of a large deployable mesh reflector are shown. Three methods of root-mean-square error calculation for large deployable mesh reflectors, namely, the nodal deviation root-mean-square error, the best-fit surface root-mean-square error, and the direct root-mean-square error, are presented. Concept of effective region is introduced. An adjusted calculation of root-mean-square error is suggested when the concept of effective region is involved. Finally, these reviewed methods of root-mean-square error calculation are applied to surface accuracy evaluation of a two-facet mesh geometry, a center-feed mesh reflector, and an offset-feed mesh reflector for demonstration and comparison.
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- PAR ID:
- 10429979
- Editor(s):
- Ghenaiet, Adel
- Date Published:
- Journal Name:
- International Journal of Aerospace Engineering
- Volume:
- 2022
- ISSN:
- 1687-5966
- Page Range / eLocation ID:
- 1 to 18
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1155/2022/5352146
