PRIMER VECTOR BASED OPTIMAL GUIDANCE FOR ORBITAL TRANSFERS IN CISLUNAR ENVIRONMENT

Spacecraft Trajectory Design, and more precisely the minimization of fuel needed in space op erations, is a topic that has increasingly attracted more interest, due to the desire of improving the efficiency of future space missions. The current investigation is inserted in this context, since it aims at providing a full optimization algorithm for fixed-time orbital transfers in the Circular Restricted Three Body Problem dynamic framework. Primer Vector theory is employed to assess optimality and provide a criterion to decrease the transfer cost by inserting intermediate impulsive manoeuvres along the trajectory. Numerical ad-hoc methods are first exploited to guess a rea sonable 2-impulses transfer and estimate the Time Of Flight, this kept constant for the rest of the process. Tests are performed on transfers between Earth-Moon Halo orbits, which have been tar geted by NASA as possible parking spots in future Moon missions, showing the results obtained in terms of fuel saving and optimality achieved