Research presented at the Salt Palace Convention Center in Salt Lake City examined how single event upsets affect neural networks on smallsat missions. As these missions increasingly use COTS processors, a charged particle striking a device can flip a single bit of memory.
According to the research, an upset in a network weight does not raise a fault condition. Instead, the network continues to operate and returns incorrect values, which can lead to downstream control loops acting on incorrect data. The standard response within cFS to memory corruption is a process restart, a method that interrupts service and discards runtime state.
The study, titled Bit-Flip Sensitivity and Selective FP32 Protection for Onboard Neural Networks in Flight Software, focused on in-place SECDED healing of an FP32 weight buffer inside NASA cFS.
