A Simultaneous Optimization Technique for Spaceplane Shape and Trajectory

This paper presents a new parallel optimization method to solve large-scale design and control optimization problems and its applications to conceptual designs of spaceplane. Generally, it takes much computing load and time to solve a large-scale optimization problem. Therefore, the new method divides the problem into several sub-problems which can be optimized in parallel. Firstly, this paper describes the way to decompose the problem and the fundamental algorithm to solve it. The important point of this study is how to deal with the conjunctive constraints among the sub-problems and define an objective function in each sub-problem. Finally, the parallel optimization method is applied to a shape and flight trajectory optimization problem of future space transportation vehicle, i.e. spaceplane. Spaceplane is considered to be impossible to develop by present technologies. For this reason, most realistic shapes and flight trajectories of spaceplane are found. The effectiveness of the proposed parallel optimization method is also demonstrated.