A new optimization method for low-thrust rendezvous trajectories in the vicinity of the Earth-Moon libration point L2 is presented. A space station at a halo-orbit and an active spacecraft (AS) in the vicinity of the orbit are considered. An iterative algorithm of differential correction is used. The numerical method is based on the precisely Moon and Sun ephemerides. As the optimization technique, the pseudo-impulse set method (discretization of the trajectory on segments and a near-uniform discrete approximation of the possible thrust directions for each segment) is applied. The method requires computation of the partial derivatives for all of the pseudo-impulses at each segment along a reference trajectory. The partial derivatives can be computed numerically for perturbed motion equations. Application examples are presented for low-thrust rendezvous trajectories with durations of 1-4 days after the transfer to a vicinity of the halo-orbit. Results of the method convergence are described. The linear approximation (i.e. the solution at the first iteration) has a good precision - no more than 1% of target state vectors. The optimization method can be used to estimate the required thrust-to-weight ratio of the active spacecraft.
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