Dynamic consistent hierarchical decoupling optimization of modular microsatellite structures for on-orbit assembly

Purpose On-orbit assembly technology is an important development direction in the field of spaceflight. Focusing on the cooperativity of microsatellite lightweighting and system dynamic performance, this study aims to propose a dynamic-consistent hierarchical decoupling optimization framework for modular satellite structural design under frequency constraints. Design/methodology/approach The dynamic stability of the satellite depends on the mechanical properties of its matrix. As it was difficult to establish an accurate model covering all structural and joint parameters for the multi-subsystem coupled satellite structure, instead of constructing a fully coupled global model at the early design stage, the multi-subsystem satellite structure is reformulated into sequential subsystem-level mass minimization problems under dynamic frequency constraints. A genetic algorithm is used as a global search engine within each subsystem optimization stage. System-level consistency is verified through finite element analysis to ensure that overall modal requirements are satisfied. Findings The genetic optimization algorithm is used in optimization design. The optimal matching of structural geometric parameters of the microsatellite is achieved. The result shows that within the base frequency range of the satellite, the proposed framework achieves significant lightweight performance while maintaining dynamic stability. Originality/value This paper presents a dynamic-performance-driven hierarchical decoupling methodology, which reduces modeling complexity and enhances engineering implementability. This framework provides a structured alternative to conventional fully coupled multidisciplinary design optimization approaches for modular on-orbit assembly systems. This method provides an effective engineering method and reproducible implementation path for the optimization design of microsatellite structure assembled on orbit by space robots or astronauts. It has reference significance for other similar satellite frame base structure design.