Optimal cooperative timefixed impulsive rendezvous
Abstract
A method was developed for determining optimal, i.e., minimum fuel, trajectories for the fixedtime cooperative rendezvous of two spacecrafts. The method assumes that the vehicles perform a minimum of three impulsive maneuvers with each vehicle being active, that is, making at least one maneuver. The cost of reference rendezvous solution is improved by an optimizer which uses an analytical gradient developed using primer vector theory and a new solution for the optimal terminal (rendezvous) maneuver. Results are presented for a large number of cases in which the allotted time for rendezvous and other problem parameters including initial relative position, engine efficiencies, initial masses, and fuel mass fractions of two vehicles are varied. Further improvement in cost may be realized when an additional, i.e., midcourse, impulse is allowed as part of one of the vehicles' trajectory. The criteria for addition of a midcourse impulse to a neighboring solution trajectory was developed. The cooperative rendezvous proves advantageous particularly in missions with relatively short durations and when fuel constraints are present.
 Publication:

Ph.D. Thesis
 Pub Date:
 1991
 Bibcode:
 1991PhDT........47M
 Keywords:

 Cost Estimates;
 Fuel Consumption;
 Mission Planning;
 Rendezvous Trajectories;
 Space Rendezvous;
 Spacecraft Maneuvers;
 Impulses;
 Spacecraft Trajectories;
 Trajectory Analysis;
 Trajectory Optimization;
 Vectors (Mathematics);
 Astrodynamics