Minimum-fuel rendezvous of two power-limited spacecarft is investigated.
Both vehicles are active and provide thrust to complete the rendezvous.
Total propellant consumption is minimized. A direct-minimization method,
direct collocation with nonlinear programming, is used to obtain cooperative
rendezvous solutions in a inverse-square gravitational field. Unconstrained
and constrained circular terminal orbits are considered. The optimal solutions
depend upon the power-to-mass ratios of the spacecraft, the initial orbits,
and the specified transfer time. Optimal cooperative rendezvous solutions
are compared with optimal active-passive solutions and with previously reported