Autonomous guidance for rendezvous phasing based on special-point-based maneuvers

An improved method based on special-point-based maneuvers is presented to realize autonomous rendezvous phasingin anear-circular orbit. The phasing segmentisdivided into three subphases (the initial subphase, the natural phasing subphase, and the adjusting subphase) according to the relationship between orbital phase angle and semimajor axis difference between the chaser and the target. Maneuver to natural phasing orbit is done in the initial subphase. In the natural phasing subphase, the phase angle between two spacecraft is reduced naturally due to the semimajor axis difference, and then the maneuver to the adjusting orbit is implemented. In the adjusting subphase, the phase angle is reduced step by step to satisfy the close rendezvous approaches requirement. In addition to the inplanemaneuvers, the coplanar orbital correctionstoeliminate the crosstrack differenceare doneinthe corresponding subphase. All orbital maneuvers are given as guidance impulses and calculated onboard autonomously. Precise orbital simulation results show that the autonomous guidance algorithm for rendezvous-phasing maneuvers is feasible.