Abstract:

The observability problem of binocular vision measurement system in spacecraft relative navigation is studied in this paper. The Fisher information matrix of system estimation is derived and the method for observability analysis based on the rank analysis of Fisher information matrix is proposed. The interrelationships among   the number and distribution of characteristic points, the rank of Fisher information matrix, and the system observability are studied. The conclusion is that at least 2 characteristic points are needed to insure the fully observation. At last, the observabilities of both monocular vision and binocular vision measurement system are compared according to differences of measurement equations under the same number of characteristic points. Simulation results of position and attitude determination for single picture confirm the conclusion obtained from the rank analysis of the Fisher information matrix.

Key words: Relative navigation, Binocular vision, Fisher information matrix, Observability