Fast MicroPython Controller for Flight Faults (FMCFF)

Nanosatellites are highly autonomous machines that operate in a harsh environment. Due to their inability to undergo physical maintenance, faultless operation is not guaranteed. Fault-detection, fault-isolation and recovery techniques (FDIR) are required to ensure uninterrupted operations and a commercially-viable lifetime of the satellite. In this paper, we present the Fast MicroPython controller for Flight Faults (FMCFF), our mechanism for detecting and mitigating faults in the spacecraft with MicroPython. MicroPython is an open source implementation of the Python 3 language optimized for microcontrollers. It is the control language for our satellites and interfaces all of its subsystems. As such, it provides access to the mechanisms required for fault detection and mitigation within the satellite. Using MicroPython for fault handling keeps interfaces coherent and reduces side effects. We show that the MicroPython runtime can be safely interrupted to fulfill our FDIR requirements in a timely manner. We verify our results using fault injection in hardware-in-the-loop (HIL) setups simulating our spacecraft.