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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                    This content will become publicly available on February 1, 2027
                            
                            Dynamic modeling and vibrations of large deployable mesh reflectors
                        
                    
    
            Large deployable mesh reflectors play a critical role in satellite communications, Earth observation, and deep-space exploration, offering high-gain antenna performance through precisely shaped reflective surfaces. Traditional dynamic modeling approaches—such as wave-based and finite element methods—often struggle to accurately capture the complex behavior of three-dimensional reflectors due to oversimplifications of cable members. To address these challenges, this paper proposes a novel spatial discretization framework that systematically decomposes cable member displacements into boundary-induced and internal components in a global Cartesian coordinate system. The framework derives a system of ordinary differential equations for each cable member by enforcing the Lagrange’s equations, capturing both longitudinal and transverse internal displacement of the cable member. Numerical simulations of a two-dimensional cable-network structure and a center-feed parabolic deployable mesh reflector with 101 nodes illustrate the improved accuracy of the proposed method in predicting vibration characteristics across a broad frequency range. Compared to standard finite element analysis, the proposed method more effectively identifies both low- and high-frequency modes and offers robust convergence and accurate prediction for both frequency and transient responses of the structure. This enhanced predictive capability underscores the significance of incorporating internal cable member displacements for reliable dynamic modeling of large deployable mesh reflectors, ultimately informing better design, control, and on-orbit performance of future space-based reflector systems. 
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                            - PAR ID:
- 10637280
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Applied Mathematical Modelling
- Volume:
- 150
- Issue:
- PA
- ISSN:
- 0307-904X
- Page Range / eLocation ID:
- 116329
- Subject(s) / Keyword(s):
- Large deployable mesh reflector Cable-network structure Dynamic modeling Vibrations Cartesian spatial discretization
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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