1. Spacecraft Anomaly Analysis and Prediction System – SAAPS
Peter Wintoft & Lars Eliasson
Swedish Institute of Space Physics

2. SAAPS Spacecraft Anomaly Analysis and Prediction System
ESA Contract 11974/96/NL/JG(SC):
Development of AI Methods in Spacecraft Anomaly Predictions
Extension of the SPEE study
Two year project (April April 2001)
Database and software

3. The model

4. SAAPS Data Sources

5. The model

6. SAAM Spacecraft Anomaly Analysis Module Plotting tools Statistics
Superposed epoch analysis
Correlations (linear and entropy based)
Cluster analysis
Pattern definition and search
Guidelines
Estimate best prediction model

9. The model

10. SAPM Spacecraft Anomaly Prediction Module
Neural network based prediction models
Real time forecast
Connects to SAAM for analysis
Anomaly index (?) and/or
Spacecraft dependent anomaly predictions

12. Space weather A definition:
Space weather refers to solar conditions that can affect the Earth's atmosphere, technological systems and human health.

16. The particle environment
Galactic Cosmic Rays (GCRs)
nuclei with energies of several GeV
modulated by the solar wind magnetic field, thus, inversely correlated with the solar cycle
The inner radiation belt (r < 2.5 RE)
protons with energies less than 600 MeV
electrons with energies less than several MeV
The outer radiation belt (r < 10 RE)
mainly electrons
highly time varying and driven by the solar wind

17. The radiation belts

18. The effect on spacecraft
A GCR or energetic proton can lead to a single event phenomena (SEP), which can be further divided into
single event upset (SEU) causing state change in digital circuits
single event latchup (SEL) causing parts to hang up
single event burnout (SEB) causing permanent damage
Electrostatic charging by
keV electrons (surface charging)
MeV electrons (internal charging)

19. Examples of satellite anomalies
AT&T Telstar, lost contact on January 11th 1997 (GCR)
Simultaneous failure of GOES-2 and -4 in November 1982 (GCR)
Intelsat K momentum wheel control circuit anomaly on January 20th 1994 (Charging)
Anik E-1 momentum wheel control circuit anomaly on January 20th 1994 (Charging)

20. SAAPS Database of space weather data and satellite anomaly data
Tools for the analysis of satellite anomalies
Models for real time predictions of satellite anomalies on time scales from hours to days

21. SAAPS Tools and models
Graphical presentations such as plots and warning signals
Statistical calculations
AI models such as Artificial Neural Networks (ANNs) and Fuzzy Systems

22. Analysis module

23. Prediction module