Reachability Approximators for Low-Thrust Trajectories

Background

Reachability analysis is a key tool in low-thrust spacecraft trajectory planning, helping determine which target states a spacecraft can reach under constraints like time, thrust, and fuel. Traditional methods compute the full set of reachable states, which can be computationally expensive and increasingly difficult for complex environments, such as multi-body systems or solar sail missions [1],[2],[3]. Efficiently understanding reachability is essential for mission design, including interplanetary transfers and small body interceptions.

Project Goals

Our team is developing a dual approach to reachability that focuses on the maximum initial mass a spacecraft can have to reach a given target within a fixed time. We apply this method across multiple dynamical environments and explore machine learning models to rapidly approximate reachable sets, enabling mission designers to quickly assess trajectory feasibility and plan low-thrust missions.

References

[1] Chen, Qi, Dong Qiao, and Changxuan Wen. "Minimum-fuel low-thrust trajectory optimization via reachability analysis and convex programming." Journal of Guidance, Control, and Dynamics 44.5 (2021): 1036-1043.

[2] Sangjin L. and Hwang I.. "Reachable set computation for spacecraft relative motion with energy-limited low-thrust." Aerospace Science and Technology 77 (2018): 180-188.

[3] Patel P. R., and D. J. Scheeres. "Rapid and automatic reachability estimation of electric propulsion spacecraft." The Journal of the Astronautical Sciences 70.6 (2023): 45.