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Experience from the in-flight calibration of the extreme ultraviolet explorer (euve) and upper atmosphere research satellite (uars) fixed head star trackers (fhsts)
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Lee, Michael |
| Copyright Year | 1995 |
| Description | Since the original post-launch calibration of the FHSTs (Fixed Head Star Trackers) on EUVE (Extreme Ultraviolet Explorer) and UARS (Upper Atmosphere Research Satellite), the Flight Dynamics task has continued to analyze the FHST performance. The algorithm used for inflight alignment of spacecraft sensors is described and the equations for the errors in the relative alignment for the simple 2 star tracker case are shown. Simulated data and real data are used to compute the covariance of the relative alignment errors. Several methods for correcting the alignment are compared and results analyzed. The specific problems seen on orbit with UARS and EUVE are then discussed. UARS has experienced anomalous tracker performance on an FHST resulting in continuous variation in apparent tracker alignment. On EUVE, the FHST residuals from the attitude determination algorithm showed a dependence on the direction of roll during survey mode. This dependence is traced back to time tagging errors and the original post launch alignment is found to be in error due to the impact of the time tagging errors on the alignment algorithm. The methods used by the FDF (Flight Dynamics Facility) to correct for these problems is described. |
| File Size | 690803 |
| Page Count | 16 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19950021358 |
| Archival Resource Key | ark:/13960/t8x974k7s |
| Language | English |
| Publisher Date | 1995-05-01 |
| Access Restriction | Open |
| Subject Keyword | Astrodynamics Optical Correction Procedure Random Noise Statistical Analysis Calibrating Extreme Ultraviolet Explorer Satellite Time Measurement Upper Atmosphere Research Satellite Uars Errors State Vectors Alignment Algorithms Covariance Star Trackers In-flight Monitoring White Noise Eigenvectors Roll Satellite Orientation Matrices Mathematics Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
