OPTIMIZATION OF A LOW-ALTITUDE TETHERED PROBE FOR MARTIAN ATMOSPHERICDUST COLLECTION

A tethered satellite system is proposed for the collection of a dust s ample from the Martian atmosphere. In a previous paper, under the assu mption of a circular orbit, a system had been designed by trading off the lowest reachable altitude versus the propellant consumption necess ary to maintain a constant altitude orbit. Because of the dust density and distribution during a Martian storm, significant improvements in the mission scenario an achieved in the present paper by considering a n elliptic orbit with dramatic reduction of propellant consumption wit h respect to our previous results. The system design is optimized in t erms of tether diameter and orbital parameters with a simplex optimiza tion algorithm that considers the propellant consumption as the cost f unction and the maximum in-plane libration and the tether tensile safe ty factor as constraints. The simulations of the system dynamics inclu de an active feedback tether control for stabilizing the tether librat ion, which, for an elliptic orbit with low periapsis, can be significa nt. The analysis shows the potential of a tethered system for collecti ng a dust sample from the Martian atmosphere.