| Autor: |
David Martin, Nasa Gsfc, Sanford Ashton, Swales Aerospace, Craig Woodruff, Quang Lam |
| Rok vydání: |
2002 |
| Předmět: |
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| Zdroj: |
AIAA Guidance, Navigation, and Control Conference and Exhibit. |
| DOI: |
10.2514/6.2002-4670 |
| Popis: |
This paper presents the design, development, and validation of a ground-based software toolkit that is under development to support the GOES N-Q spacecraft Stellar Inertial Attitude Determination (SIAD) system performance monitoring and optimization during the PostLaunch Test (PLT) period. The main effort is to have a set of tools ready to provide on-orbit performance analysis of the SIAD system and its associated sensor suite, consisting of three inertial reference units (IRU) and three star trackers (ST). The SIAD system employs a six-state Kalman filter whose performance is essentially dictated by the knowledge of its process noise Q and measurement noise R. These two covariance matrices are computed as a function of the IRU noise and ST noise, respectively. The toolkit under development will provide the capability to extract and characterize ST noise and IRU noise so that the Q and R matrices can be recomputed, tested, and optimized on the ground. These tools will use a groundbased SIAD filter for performance improvement and validation. Design of these tools including Q and R determination based on telemetry data and the ability to run the filter using in-flight values of Q and R or option to use these newly extracted Q and R matrices for performance comparison are presented. In addition, nonlinear filtering and identification scheme of ST Low Spatial Frequency (LSF) noise parameters by postprocessing the composite ST residuals for ST noise cancellation is also briefly discussed. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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