OPTEC - K.U.Leuven Center of Excellence: Optimization in Engineering

“Interplanetary Spacecraft Trajectory Optimization”

Marnix Volckaert (T.U.Delft)

In order to learn more about the origin of our solar system, it is crucial to send spacecraft to other planets and their moons. Furthermore, the possibility of sending humans to another planet, such as Mars, requires the technology to transfer a spacecraft from the Earth to the other planet. Such a complex undertaking can only be achieved if the trajectory followed by the spacecraft is highly optimized, for example in terms of the required propellant mass.

Finding the trajectory that uses the least amount of propellant is difficult. The search space is quasi unlimited, and there are multiple local optima. The motion of the spacecraft is described by complex astrodynamical concepts, that can be used to the advantage, for example during a gravity assist maneuver.

Trajectory optimization techniques can be divided into analytical methods and numerical methods. The analytical methods are generally much faster but can be inaccurate because of their simplifying assumptions. The numerical methods can be more accurate, but are usually slower, because they rely on numerical integration of the spacecraft's state.

In this presentation an overview will be given of different trajectory optimization methods, both analytical and numerical, including their application to real-life and concept missions.