Discovering outliers in the Mars Express thermal power consumption patterns
This addresses the need for operators to monitor and handle deviations in spacecraft behavior, but it is incremental as it applies an existing method to a specific domain.
The paper tackled the problem of detecting outliers in the thermal power consumption patterns of the Mars Express spacecraft, which should be roughly periodic but was found to be irregular, and successfully detected these irregularities using long short-term memory neural networks, opening possibilities for automatic outlier detection.
The Mars Express (MEX) spacecraft has been orbiting Mars since 2004. The operators need to constantly monitor its behavior and handle sporadic deviations (outliers) from the expected patterns of measurements of quantities that the satellite is sending to Earth. In this paper, we analyze the patterns of the electrical power consumption of MEX's thermal subsystem, that maintains the spacecraft's temperature at the desired level. The consumption is not constant, but should be roughly periodic in the short term, with the period that corresponds to one orbit around Mars. By using long short-term memory neural networks, we show that the consumption pattern is more irregular than expected, and successfully detect such irregularities, opening possibility for automatic outlier detection on MEX in the future.