Help needed to diagnose a failed auto mission resulting in a crash V3.0.1

I programmed the following mission:

It is a quad, 3DR frame, nothing fancy, APM running V3.0.1.

It executed the auto mission until waypoint 3 then I saw the quad go down in an apparent controlled manner (it is not like i lost a prop) still moving toward waypoint 4, as if the quad wanted to land or something.

This is the google earth picture of the auto mission until interrupted at waypoint3:

I think I then switched to stab mode to recoup its descent but it crashed flipping upside down. I broke the telemetry module (antenna connector) in this crash.

Can anyone help me diagnose what happened and caused this strange crash ?

I see no reason : motors ok, propellers ok, battery was far from empty, I do not think I broke the geofence, ...

I looked at the onboard video and at the moment of the incident I hear a drop in motor power. Looking at the battery voltage it is not below the ESC soft power cutoff though. So I do not know what happened.

here attached the log and kmz files

2013-08-07 15-03 77.log

2013-08-07 15-03 77.kmz

2013-08-07 14-18-42.tlog

I will look at the log files, but what you describe is a controlled descent, very similar to an RTL, but without actually returning to "Home".

I experienced this last night on my quad, not in AUTO, but at the time it happened I was in STABILIZE. The quad stopped responding, and landed.

Everything was okay, I couldn't (at first) get it to Re-Arm. I had to switch the flight mode to LOITER then back to STABILIZE to re-arm.

What this is a "LAND" this will happen if the quad loses a GPS fix. This is on the GPS FAILSAFE parameter.

It is ENABLED by default, and will initiate a LAND if the GPS fix is lost for 5 seconds; see the manual extract here:

The GPS Failsafe is enabled by default but you can enable or disable it on the Mission Planner’s Advanced Parameter List, by set the FS_GPS_ENABLE parameter to 0 (disable) or 1 (enable).
If you lose GPS contact for 5 seconds while you are in AUTO, GUIDED, LOITER, RTL, CIRCLE or POSITION mode it will initiate a LAND.

http://copter.ardupilot.com/wiki/failsafe/

I will have a look at the logs for you though, but that is what I suspect happened,

Replies

Emin Bu August 8, 2013 at 2:29am

You know what happened

http://diydrones.com/group/arducopterusergroup/forum/topics/optimiz...

This is why it is important to isolate vibrations from the APM, otherwise dangerous things can happen resulting in loss of craft or worse harm to operator or bystanders.
Ben Cairns August 7, 2013 at 6:58am
I will look at the log files, but what you describe is a controlled descent, very similar to an RTL, but without actually returning to "Home".

I experienced this last night on my quad, not in AUTO, but at the time it happened I was in STABILIZE. The quad stopped responding, and landed.

Everything was okay, I couldn't (at first) get it to Re-Arm. I had to switch the flight mode to LOITER then back to STABILIZE to re-arm.

What this is a "LAND" this will happen if the quad loses a GPS fix. This is on the GPS FAILSAFE parameter.

It is ENABLED by default, and will initiate a LAND if the GPS fix is lost for 5 seconds; see the manual extract here:
- The GPS Failsafe is enabled by default but you can enable or disable it on the Mission Planner’s Advanced Parameter List, by set the FS_GPS_ENABLE parameter to 0 (disable) or 1 (enable).
- If you lose GPS contact for 5 seconds while you are in AUTO, GUIDED, LOITER, RTL, CIRCLE or POSITION mode it will initiate a LAND.
http://copter.ardupilot.com/wiki/failsafe/

I will have a look at the logs for you though, but that is what I suspect happened,

This reply was deleted.

ArduCopter User Group

Replies