To achieve the highest accuracy boresight pointing performance the Hubble Space Telescope (HST) uses attitude feedback from the fine guidance sensors (FGS). There are three FGSs on board HST. During normal operations, one sensor monitors the spacecraft pitch and yaw, another monitors the roll and the third is the redundant unit. Each FGS senses wavefront tilt interferometrically and converts that tilt into spacecraft pointing error. The presence of spherical aberration affects the signal from the instrument causing a reduction in acquisition and tracking performance on targets whose magnitudes are fainter than 14. This paper documents the efforts to optimize uplinkable FGS parameters in order to increase the probability of target acquisition that is better than 98 percent over the entire field of view. To this end, the paper describes the Monte Carlo simulator used in deriving the optimized values for the FGS acquisition and discusses methods for testing the new parameters prior to on-orbit verification.
Optimization of the Hubble Space Telescope fine guidance sensor target-acquisition parameters
1998
11 Seiten, 5 Quellen
Conference paper
English