I built a copter for a friend, who was out flying a mapping mission in auto. Just prior to the last waypoint the chute deployed. After reviewing the logs I cannot determine why the chute deployed. It looks as thought the copter is flying just fine and there is no 20 degree mismatch or manual deployment. Note that the copter is an s900 hexcopter, with a separate battery for chute power. The upside, is that the copter landed with very minor damage from a deployment height of 80m. Skycat chute - the big one. Sadly the logs stop when the chute deployed. The log records the chute event at the very end, but I cannot see an RCOUT that would correspond with the chute deploying. Chute is on ch 8.
You had a brown out reset or a total failure of your power system. Other than that the copter was flying perfect, well tuned machine. You have to look at the power tab in the log viewer. As you can see the vcc is bouncing between ~4.2 to 4.7 volts. This is not good. Your back up power was at 7.2 volts which is too high and the power switcher on the Pixhawk will reject it. When the log just ends like that it almost always means the thing lost power, could be even a quick drop below min volts and the thing will reboot. Smart to have a chute on a big machine like that. Fix the power system before it flies again.
The Pixhawk records everything!
So this is a good thing, correct? If the Pixhawk ever browns out for whatever reason, the chute will auto-deploy to save the craft?
I think he must have been using an independent trigger to fire the chute. Has nothing to do with the Pixhawk as it lost power and there is no output. He had a second battery for the chute ejection system so I assume he had one of these things.
It has it's own imu that detects an a falling or tumbling copter and fires the chute.