Research On The Scheduling Approaches Of Multi-spacecraft Rendezvous Mission For On-orbit Refueling

On-orbit refueling is a kind of on-orbit service, which aims to refuel the satellites which move on the orbit. In order to complete the mission in a more economical way, it is preferred to refuel multi-spacecraft in one mission. This paper researches on the scheduling approaches of multi-spacecraft rendezvous mission for on-orbit refueling to find the optimal way for the mission. The transfer of the service spacecraft is conducted in the way of two impulses.1. Optimal scheduling of multispacecraft refueling based on cooperative maneuverBased on the dynamics of two-body model, a rendezvous model for two far spacecraft based on impulse maneuver is established. A fixed-time transfer problem between two points fixed on the two orbits is solved using the solution of the multiple-revolution Lambert problem. But the previous method is time-costing that the optimization solver could not use it for many times. In order to solve this problem, a contour plot of the cost is obtained as a function of the separation angle and the transfer time. This contour plot along with a sliding rule helps one find the optimal initial and terminal coasting periods and, thus, yields solutions to the original rendezvous problem. This method was used to calculate the globally optimal solution for a moving-target rendezvous problem in the following scenario.2. The programming of on-orbit refueling mission for geosynchronous satellitesThe programming of on-orbit refueling mission is studied. The refueling mission for geosynchronous satellites is chosen as the study object. The mathematical model is established and decomposed into four subproblems: the problem of solving the number of the service satellites, optimal path planning problem and optimal launching problem. The mission programming problem is also hierarchical decomposed. It is very costive for the satellite to transfer from GTO to GSO, and in the programming, this part of fuel cost is taken into consideration. The case that one rocket carries more than one service spacecraft is also taken into consideration. The main factors which influence the cost are ranked. The problem is solved by genetic algorithm and corresponding genetic operators are designed.3. Mission programming of Peer-to-Peer refueling on non-coplanar circular orbit.The mission programming of Peer-to-Peer refueling on non-coplanar circular orbit is studied in this paper. Firstly, the mathematic model for the problem is set up, and the programming problem is summed up as a three-index match problem. Secondly, the flow of the algorithm for the problem is designed, and the combination of Kuhn-Mundres algorithm and the integer genetic algorithm is adopted, the convergence was accelerated and the global optimization is guaranteed. At last, two constellations on non-coplanar circular orbit which has a small intersection angle is considered as an example, the result shows that the proposed model and algorithm are efficient.4. The scheduling of multispacecraft refueling based on cooperative maneuver in a circular orbit.In the proposed scheme, both of the Single Service Vehicle(SSV) and the Target Satellite(TS) perform the orbital transfer to complete the rendezvous at the service places. A Mixed Integer Nonlinear Programming(MINLP) model for the mission is first built, then a two-level hybrid optimization approach is proposed for determining the strategy, and the optimal solution is successfully obtained by using an algorithm which is a combination of Multi-island Genetic Algorithm and Sequential Quadratic Programming. Results show that: comparing with the non-cooperative strategy, the cooperative strategy can save fuel significantly.The work of this paper can be taken as a valuable reference for the mission programming of multispacecraft refueling.