ExoMars alternative escape trajectories with Soyuz/Fregat.

The objectives of ExoMars are to inject an orbiter around Mars and to land a rover on the surface to look for possible traces of life. During the first stages of the feasibility analysis, the mass margin of the orbiter was very small for a direct transfer in the Soyuz/Fregat scenario. An analysis of the combined use of lunar swing-bys and the Sun gravity gradient is performed with WESBOT in order to obtain alternative trajectories for injecting higher mass into Mars transfer.

Autonomous low-thrust guidance: application to SMART-1 and BepiColombo.

Several techniques have been developed to obtain optimum trajectories with low-thrust propulsion. However, few low-thrust guidance schemes have been investigated to fly the reference optimum trajectories. The guidance algorithm successfully employed in the DeepSpace1 mission was the first approximation through the presented guidance schemes, valid for various interplanetary low-thrust trajectories, independently of the optimization technique they result from.