Optimal deployment and return trajectories for a tether-assisted re-entry mission

Abstract

Optimal deployment and return trajectories for a tether-assisted m-entry mission are provided. For the deployment procedure a dynamic release is considered. The optimal control problem minimizes the overall control input during deployment. The impact of a stability constraint is investigated and shows, that subject to a given perigee reduction the attainable maxhmuu in-plane angle is reduced by 42% to 45” whereas the required tether length is increased by only 16% to 35lun Corresponding optimal return trajectories for a re-entry capsule with a medium lift-to-drag ratio are obtained. The control effort is minimized and path constraints on both heating rate aud load factor are considered. The results are compared to a solution of a near-optimal guidance law.