Echtzeitfähige Trajektorien-Synthese mittels multivariater Interpolationsverfahren am Beispiel eines Mondlandemanövers

Abstract

Although the NASA already successfully landed on the Moon in the 60s and 70s of the 20th century, the subject of Moon landing is an important research field of aerospace up to today. The European Space Agency ESA investigates concepts for a successful lunar mission in the next decade. A critical point is the safe and precise landing of the lunar module on the Moon's surface. In the context of conventional approaches, the calculation of an optimal trajectory takes place, due to limited onboard computing capacity, in advance of a mission. The assumed system parameters and initial conditions for the beginning of a maneuver do not normally correspond with the conditions encountered later during the mission. Such deviations are compensated by a calculated tracking control for a specified optimal trajectory. In this article, a new approach is proposed, which increases the area of initial conditions and system parameters that lead to a successful landing. Thereto a nearly optimal interpolation-based trajectory and tracking control, to an actually occurring set of initial conditions and system parameters to the beginning of a maneuver, is calculated, from a grid of pre-calculated optimal trajectories and corresponding tracking controls. The general formulation allows the application of the developed approach to general perturbed optimal control problems. Practicality and relevance is demonstrated by applying it to a Moon landing maneuver.