New Method for Assessing Spacecraft Reachability Using Maximum Initial Mass Optimization
A new study introduces a reformulated approach to low-thrust spacecraft trajectory reachability analysis that replaces grid-based optimal control sweeps with a scalar maximum-initial-mass (MIM) optimization problem for each target state. Classical methods require extensive forward simulations over grids of terminal states, making them computationally prohibitive for high-dimensional or strongly nonlinear systems such as cislunar or solar sail missions. The work further trains residual neural networks as surrogate models of the MIM field, enabling rapid feasibility assessment for preliminary mission design.
Presented at the 30th International Symposium on Space Flight Dynamics (June 2026, Toulouse), this preprint by Giacomo Acciarini and colleagues proposes a dual reformulation of the spacecraft reachability problem for low-thrust propulsion systems. Rather than solving many optimal control problems across a grid of terminal states, the method asks a single scalar question for each target: what is the maximum initial spacecraft mass that still permits a successful transfer within fixed time and boundary conditions? A target is deemed reachable if the actual initial mass falls below this threshold, converting a high-dimensional feasibility problem into a smooth scalar field. The authors derive indirect maximum-initial-mass (MIM) formulations for both electric low-thrust and solar-sail dynamics, with the solar-sail variant optimizing a scalar sail-strength parameter instead of mass. To further accelerate evaluation, they train data-driven surrogate models on the MIM scalar field, finding that residual neural networks outperform standard fully connected architectures in accuracy, training stability, and model complexity. The combined framework is positioned as a practical tool for rapid preliminary mission design and feasibility screening in complex dynamical environments.
What's missing
The preprint has not yet undergone formal peer review. Generalization performance across a wide range of mission scenarios beyond the cases tested (e.g., highly perturbed cislunar orbits, multi-revolution transfers) remains an open question.
What different sources said
- arXiv physicsCenter
Reachability for Low-Thrust Trajectories via Maximum Initial Mass
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