ESA GNC Conference Papers Repository

Since its first developments in the 80’s the aerocapture has always been a promising insertion technique to place a spacecraft on a parking orbit after an interplanetary cruise. However it has never been in-flight demonstrated, defining an aerocapture mission around Earth yielding numerous safety issues in addition of requiring highly energetic conditions at entry interface. It is clearly less the case for an exploration mission. In order to deplete the energy of the spacecraft along its atmospheric path new aerocapture principles emerged in the recent years by replacing the classic lift modulation by a single or multiple-event drag modulation. As for any aerocapture mission, propulsive corrections will have to be performed after atmosphere’s exit in order to raise the periapsis and then to adjust the apoapsis to the targeted value and, if really needed, to correct the inclination. But the main advantage of such new technique is to ease the design of the spacecraft that does no more require a dedicated RCS to control the attitude of the vehicle during its atmospheric path but only a mechanical deployment /jettisoning of a rigid or inflatable heat shield, the spacecraft being thus passively stabilized at a low spinning rate. AERODEM is an aerocapture demonstration mission at Mars studied for ESA that should rely on such insertion technique. Within the frame of past ESA or EU-funded studies, different aerocapture guidance schemes have been designed at ArianeGroup in order to reach an elliptic intermediate orbit using the lift modulation technique. Among those ones and after some adaptation to manage only the drag a simple and robust numerical predictor-corrector guidance scheme has been selected to perform such mission. This paper aims at presenting the retained guidance design whose preliminary performance is illustrated by Monte-Carlo simulations for two generic missions termed as standalone, for a 470 kg spacecraft, or piggy-back, for a 155 kg spacecraft.