Event Detection and Characterization During Autonomous Interplanetary Navigation
| Autor: | Robert H. Bishop, Todd A. Ely, Timothy Crain |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
Artificial neural network
Computer science Event (computing) Applied Mathematics Real-time computing Aerospace Engineering Navigation system NASA Deep Space Network Kalman filter Interplanetary mission Space and Planetary Science Control and Systems Engineering Component (UML) Genetic algorithm Electrical and Electronic Engineering |
| Zdroj: | Journal of Guidance, Control, and Dynamics. 25:394-403 |
| ISSN: | 1533-3884 0731-5090 |
| Popis: | A prototype autonomous/adaptive interplanetary navigation system employing neural networks and genetic algorithms is introduced. This system consists of a near real-time autonomous monitoring component and an ofe ineadaptivemodelingcomponent.Unexpecteddynamicormeasurementeventstrigger1 )alertstonavigatorsand 2) recommendations for modifying the appropriate model parameters to improve e ltering. The autonomous component analyzes tracking measurement residuals to e rst detect and then characterize the unexpected event. Once an environment change has been detected and characterized, the adaptive modeling component then modie es the necessary modelparametersto bring thetracking e lterback into optimal operation.Theautonomousmonitoremploys a hierarchical mixture-of-experts model where the experts are extended Kalman e lters organized into banks regulated by two levels of single-layer neural networks. The autonomous monitor is the focus of this presentation and demonstrates the ability to detect successfully the occurrence and to differentiate between the characteristics of unexpected discrete velocity changes and continuous dynamic changes. These environment changes are represented by an unmodeled impulsive maneuver and by solar radiation pressure surface mismodeling, respectively. The robust decision-making capability of this approach is further demonstrated by successfully characterizing three successive environment changes. All experiments were performed on recorded Mars Pathe nder two-way Doppler data from the period of 4 February 1997 to 17 April 1997. |
| Databáze: | OpenAIRE |
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