SINGULAR MANEUVERS IN ANGLES-ONLY INITIAL RELATIVE-ORBIT DETERMINATION

A maneuver performed by either the chief or deputy spacecraft can provide observability in relative-orbit determination using angles-only measurements and linear, Cartesian dynamics model. This paper, however, presents solutions for maneuvers that result in singular measurement equations and therefore do not provide full-state observability. The singular maneuvers produce changes in the relative position that are proportional to the expected line of sight, and thus produce no changes in the measurements. Additionally, the solution covariance and bias in the presence of noisy measurements is analyzed. This analysis provides insight into desirable maneuvers that improve the accuracy of the initial relative orbit determination.