小推力多天体借力轨道的分段初始化方法

To address the numerical optimization convergence difficulties in low-thrust multi-body gravity assist transfers，which arise from strongly coupled constraints and high sensitivity to initial values，a segmented initialization method based on the finite-burn four-impulse approximation（FBFA）is proposed. This method uses FBFA to rapidly map gravity-assist impulse solutions into feasible low-thrust solutions，effectively avoiding the convergence problems of traditional numerical optimization. On this basis，a sequential convex optimization method is adopted to iteratively refine the feasible low-thrust solution and obtain a fuel-optimal low-thrust gravity assist trajectory；meanwhile，a maneuver profile is constructed based on the feasible solution to improve the algorithm’s convergence efficiency. Trajectory design is conducted taking a Jupiter-Uranus sequential flyby mission as an example. The results show that，compared with traditional algorithms，the proposed method reduces the number of convergence iterations and computational cost by approximately 70% while ensuring solution accuracy. It enables efficient initialization of low-thrust multi-body gravity assist trajectories and holds practical engineering application value.