New Method for Assessing Spacecraft Reachability Using Maximum Initial Mass Optimization
Researchers have developed a new approach to determine which orbital destinations are reachable by spacecraft with low-thrust propulsion systems by reformulating the problem as a maximum initial mass optimization rather than computing reachable sets directly. The method addresses computational limitations of classical approaches, particularly for complex scenarios like cislunar missions and solar sail trajectories. This advancement could accelerate preliminary mission design and feasibility assessment for future space missions.
The study introduces a dual formulation for reachability analysis in low-thrust spacecraft trajectory optimization. Rather than the traditional approach of solving many optimal control problems across grids of terminal states, the new method determines the maximum allowable initial mass that permits a successful transfer to a given target within fixed time and boundary conditions. This reformulation converts the problem into a scalar optimization for each target, producing a smooth scalar field that encodes feasibility information equivalent to classical reachable sets. The researchers developed indirect maximum-initial-mass (MIM) formulations for both electric low-thrust and solar-sail dynamics. To further enhance practical applicability, they constructed data-driven surrogate models using neural networks—particularly residual networks—to approximate the MIM-based reachability indicator, enabling rapid feasibility evaluation while maintaining numerical advantages of the dual formulation.
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- arXiv physicsCenter
Reachability for Low-Thrust Trajectories via Maximum Initial Mass
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