CRASH: AC 4.0.3, WatchDog reset in-flight while executing a mission


We were unfortunate and had a drone suddenly falling from sky while it was executing a mission.
This was a short mission consisting of waypoints, speed changes, DO_SET_ROI and LOITER_TIME commands. Altough WatchDog error tells already that something is really badly wrong, but it was fortunate that it was just hardware which got destroyed.

The WatchDog reset happened about few seconds after executing the last mission command, which was LOITER_TIME for 10 seconds.

The log is split in two halves, where the first is before the lockup and second after watchdog reset.
Heres the watchdog message for the most hasty readers:

What I can say about that is:

Task: -2 if the fast loop had started
FL: Fault Line 100, the source code line number where the fault occurred.
FT: Fault type 3. 3 = Hard Fault (the most common)
FA: 404947019, Fault Address (in memory)
FP: 183, Thread Priority
ICSR : 4196355, Interrupt Control and State Register

Below is a log prior the WatchDog reset

Below is log after WatchDog reset

Below is telemetry log

My sincere hope is that the causal can be found and be fixed/mitigated.

1 Like

Please make these accessible without a request…

Sorry about that @peterbarker. That is fixed now.

Should I make an issue to ardupilot github, to have more relevant audience or will any of you mods/devs prefer to do that?

github issue would be good, thanks!


Issue is now done