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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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A New Approach to Nonlinear Dynamic Modeling and Vibration Analysis of Tensegrity Structures
Tensegrity structures have experienced continued research and development interests in the past several decades. Revealing dynamic characteristics of a tensegrity structure, for example: vibration analysis, is an important objective in structural design and analysis. Traditional dynamic modeling methods are inaccurate in predicting dynamic responding of a tensegrity structure, due to their neglection of internal displacements of structure members. To solve this issue, a new nonlinear dynamic modeling method for tensegrity structures is proposed in this paper. This method defines position of a structure member as a summation of boundary-induced terms and internal terms in a global coordinate system. A nonlinear dynamic model of a tensegrity structure is derived from Lagrange equation, as a system of ordinary differential equations. This dynamic model can be linearized at an equilibrium configuration for vibration analysis. As shown in simulation results, the proposed method can predict natural frequencies of a tensegrity structure with a better accuracy than the traditional methods. Unlike the traditional methods that can only predict dynamic responses in a low frequency domain, the proposed method can also reveal dynamic responses of a tensegrity structure in a higher frequency domain by only using a small number of internal terms.
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- PAR ID:
- 10429977
- Date Published:
- Journal Name:
- ASME 2022 International Mechanical Engineering Congress and Exposition
- 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
- Conference Paper:
- https://doi.org/10.1115/IMECE2022-94746
