Maybe someone can help me understand why my copter that has been working great screwed up on my today resulting in 2 crashes. I was in loiter mode and for some reason it switched to land mode on me. Fail safe?? It tilled over (because I was trying to correct it not knowing it was in land mode). So I then tried to hover it in stabilize mode and it flips over on takeoff. Maybe someone could help me understand what when wrong. Copter has been great up till now.
Are you using mission planner?
If you look at the log it says it went into land mode due to an EKF-1 failsafe.
There are several EKF warnings
Even if you aren’t confident looking at logs I would suggest looking anyway. These errors are shown on the plot time line when plotting data. Mission planner showing you them in red as simple warning messgaes (no user interpretation of wigglies 
. Not a lecture, just if you try to help your self a bit you might be able to point your question more precisely, hopefully getting a batter response. People go a bit blind to I crashed can you help me, although you did post the log! which is ace, many don’t and its impossible to comment without in most cases. If you have looked at the log apologies, maybe just say what you have seen and point your question rather than posting a generic crash thread…they tend to merge into one and people go blind to it.
The other tool you should use is the auto analysis too which shows the following.
Test: Autotune = UNKNOWN - No ATUN log data
Test: Balance/Twist = GOOD -
Test: Brownout = GOOD -
Test: Compass = FAIL - Large change in mag_field (37.60%)
Max mag field length (606.47) > recommended (550.00)
Test: Dupe Log Data = GOOD -
Test: Empty = GOOD -
Test: Event/Failsafe = FAIL - ERR found: CRASH
Test: GPS = GOOD -
Test: IMU Mismatch = GOOD - (Mismatch: 0.21, WARN: 0.75, FAIL: 1.50)
Test: Parameters = GOOD -
Test: PM = GOOD -
Test: Pitch/Roll = GOOD -
Test: Thrust = GOOD -
Test: VCC = GOOD -
I think the compass came up as a fail due to the crash showing a large MagZ change, in flight I can’t see anything wrong with it. I think that is just the simple test getting confused in this case.
You must have it set to land on fail safe in your failsafe settings.
As to why you got an EKF error, I don’t know, I haven’t learnt the EKF side of things yet.
It’s on my want to do list, but hopefully someone with better knowledge will come along.
Stu
although just reading this
copter.ardupilot.com/wiki/ekf-in … it_trigger
it says "The EKF check runs only on the Pixhawk and only when the EKF is being used as the primary source for attitude and position estimates (i.e. AHRS_EKF_USE = 1). " but yours is set to 0
but like I said I am unfamilliar with EKF
RabbitStu,
First let me thank you for taking the time to look this over as well as giving me advice. I am quite new to the world of pixhawk and apm copter. I did yank the logs and give them a look over myself but felt a bit lost on what to look at specifically. I did take a look at the “auto analysis” in mission planner and got that same info. I also searched the forums to see if i could locate an answer. I figured by posting the logs that someone much more knowledgeable might point me in the correct direction. The EKF error I would have never even thought to look at without your help. I read this here… copter.ardupilot.com/wiki/downlo … n-planner/ on how to view the logs. Is there another guide that gets a bit more in depth on reading these logs? I am very willing to learn and I really appreciate all your help.
Thanks again,
Wes
OK that’s cool. hopefully one of the experts will be along to answer for you.
RabbitStu,
Could you tell me what value you looked at on the log file to determine the EKF error? (prob a dumb question but I am honestly lost) Trying to understand how you found that information.
Thanks
All I did was plot some data in mission planner. It appeared at top of the graph indicating when the issue happened. Will try and post this evening on my pc after work.
sent from my phone so apologies for any typos
Here is an an example I posted for some one else. Its not your log but shows what I mean. The red boxes at the top of the graph. viewtopic.php?t=11022
sent from my phone so apologies for any typos
RabbitStu,
What data were you plotting specifically? I am unable to fine these EKF errors. I am not really sure what data I should be looking at. Maybe you could post a photo of my log file plotted or just provide me the data types you are plotting on the graph? Thanks again for trying to help me on this. I feel kinda dumb not knowing what to look for. Really am trying to learn how to perform these tasks on my own.
Thanks
Wes
Hi Wes,
I tried to reply at lunch time but the IT and work thwarted me
All I plotted was the RCOut values, I commonly look at these early on when checking someones logs. they aren’t EKF specific but fail safes show up at the top of the plot when they occur in the time line.
There are various EKF specific logs in your file, but I don’t know wnough about EKF to evaluate them. Maybe edit your title to include EKF Failsafe to catch the eye of a dev. EKF is a fairly specialist subject and new to APM so not many understand it yet.
Are you using Mission planner or APM planner, I am using mission planner and it shows as per the screenshot attached.
[attachment=0]DaOne.jpg[/attachment]
Ok I got it figured out. I was using a older version of mission planner thinking it was the latest one. The red error messages never showed up on mine. Thank you again for all your help. I will edit the title as you suggested. Hopefully someone with knowledge of EKF will be able to help.
Thanks again,
Wes