Optimal Planning of Multiple Geosynchronous Spacecraft Flyby Inspection Mission with Multiple Servicing Space Robots

The optimization of multiple geosynchronous spacecraft inspection problem (MGSIP) with multiple servicing space robots (SSRs) is studied in this paper. A new economical maneuver strategy for visiting multiple geosynchronous spacecraft orbiting in different orbital planes is proposed. Specifically, multiple SSRs are placed in equatorial high eccentric orbits initially and two orbital maneuvers are exerted at perigee to adjust the apogee of the SSR for every flyby inspection. Subsequently, the targets will be visited when they fly through the ascending or descending nodes of their orbits. The MGSIP could be formulated as a location routing problem with an embedded transfer problem and the objective is to find the optimal planning schemes with minimum fuel consumption. The optimization approach developed here uses two nested loops: an outer-loop problem solver that optimizes the location of each SSR, task assignment and visiting sequence, and an inner-loop problem solver that finds the optimal trajectory for a given outer-loop solution. Genetic algorithm is employed to solve the outer-loop problem and we propose a resolution approach based on branch and bound algorithm to solve the inner-loop problem quickly. Finally, it is shown that the proposed approach is valid and effective by applying it to several numerical test cases.