DECOMPOSITION APPROACH TO SOLVING THE ALL-UP TRAJECTORY OPTIMIZATION PROBLEM

This paper describes a new approach to solving the all-up (ground to mission) trajectory optimization problem. The problem considered in this paper is that of placing a maximum payload into a specified orbit, where a booster is used to place the payload in a low Earth parking orbit from which an upper stage transfers the payload to its mission orbit. One approach to solving the all-up problem has been to combine the booster and upper stage into one large simulation/optimization problem; however, this results in a difficult problem that is computationally expensive to solve. The algorithm proposed in this paper does not require any all-up trajectories to be explicitly optimized, but simulates separately the booster and upper stage. The algorithm is based on solving the maximum throw weight to a park orbit (for the booster), maximum payload transfer from the park orbit to the mission orbit (for the upper stage), and a coordination problem that adjusts the park orbit parameters to find the all-up optimum (maximum) payload to the mission orbit.