Guidance and navigation system design of R-bar approach for rendezvous and docking

Abstract

This paper focuses on the R-bar and the V-bar approaching methods as viewed from various aspects such as control, orbit dynamics, abort characteristics, and relative navigation. Differences in the combination of the outputs of the Rendezvous LOS Sensor and other attitude sensors are clarified by the analytical derivation of their kinematical relationships, which provides a basis for the attitude control. Following that, based on the orbit dynamics, it is shown that V-bar has benefits for holding, and R-bar has benefits for quick approach and recovery. Finally, it is shown that the positional accuracy in the approach direction estimated from GPS signals is better in the V-bar approach than in the Rbar approach.