Integrated Optimization of Ascent Trajectory and SRM Design of Multistage Launch Vehicles
This work addresses the problem of improving launch vehicle efficiency for space missions, but it is incremental as it applies existing optimization methods to a specific case.
The paper tackles the concurrent optimization of first-stage design and ascent trajectory for a Vega-derived light launch vehicle, achieving payload maximization into a target orbit while respecting design constraints.
This paper presents a methodology for the concurrent first-stage preliminary design and ascent trajectory optimization, with application to a Vega-derived Light Launch Vehicle. The reuse as first stage of an existing upper-stage (Zefiro 40) requires a propellant grain geometry redesign, in order to account for the mutated operating conditions. An optimization code based on the parallel running of several Differential Evolution algorithms is used to find the optimal internal pressure law during Z40 operation, together with the optimal thrust direction and other relevant flight parameters of the entire ascent trajectory. Payload injected into a target orbit is maximized, while respecting multiple design constraints, either involving the alone solid rocket motor or dependent on the actual flight trajectory. Numerical results for SSO injection are presented.