Can someone with experience look at this bin log file from a minor crash?

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Can someone with lots of experience with bin logs analysis look at the attached bin file and see why you think a brand new Solo decided it wanted to do something no good? This was the second flight since new. The first flight was perfectly fine. This flight when it was in hover and should be staying reasonably stable it started to drift, very slowly and then it started to drift faster and faster then it yawed sharply and descended into the ground. Luckily it did no physical damage. I cleaned it up and then proceeded to go through the compass and level calibrations. Afterwards I have flown it a few times and I think it seems fine.

I am wondering if the stock GPS chips are really not good enough and perhaps it lost GPS signal so it had no way to know which end was up. Just a guess.

I plan to upgrade both my solos to the mRo GPS u-Blox Neo-M8N GPS units soon. Perhaps this experience is a nudge that direction if it turns out to be GPS related.

Speaking of my other Solo. I apparently don't have a lot of luck with 3DR Solo drones. The first is on its way back to 3DR for replacement due to what I am told was a brown-out. Strangely it did basically the same thing as my new one just did except it slammed down on the concrete drive and did damage to it. It was way more violent in how it freaked out.

Thanks for taking a look!! I sent the logs to 3DR also. It'll be interesting what opinions they have and my 3DRPilots friends do!

Thanks!
 

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For future reference, make sure you have your A and/or B buttons programmed to Fly:manual mode. Once it started drifting, had you pressed a button programmed to this mode, you could have taken control and recovered. I believe your assumption was right; GPS glitch...
 
Can you describe the area where this too place? I agree it sounds like the GPS was being stupid. But I'd like to hear what made up the surroundings.
 
Can you describe the area where this too place? I agree it sounds like the GPS was being stupid. But I'd like to hear what made up the surroundings.

I live out in the country and I was in my front yard. It was 70 degrees, zero wind, not a cloud in the sky. There should not have been any wireless interference. The houses around me are 300+ yards away if not more. Do you know how to get info out of these logs?

Thanks!!
 
I live out in the country and I was in my front yard. It was 70 degrees, zero wind, not a cloud in the sky. There should not have been any wireless interference. The houses around me are 300+ yards away if not more. Do you know how to get info out of these logs?

Thanks!!
You can view all the information by downloading Mission Planner (free) onto a PC. Then you can view all the parameters and watch a replay of the flight.
I don't know how to interpret what all the parameters mean- takes more learned people than I.
 
Can you describe everything you did from the time you took it out of the bag to the time you lifted off?

Looks like major compass drift. Where the graphs go way off is the crash. The oscillation leading up to is where it started going bad.
5Z1ORIP.png


All three accelerometers remained consistent. So nothing wrong there.
uCLK3cI.png


Pitch and roll was responding as intended, so no mechanical failure.
ohoYbAe.png
 
Can you describe everything you did from the time you took it out of the bag to the time you lifted off?

Looks like major compass drift. Where the graphs go way off is the crash. The oscillation leading up to is where it started going bad.
5Z1ORIP.png


All three accelerometers remained consistent. So nothing wrong there.
uCLK3cI.png


Pitch and roll was responding as intended, so no mechanical failure.
ohoYbAe.png
Hey Pedals2Paddles.. Thank you for the info. After this happened I ran through the two calibrations and since then I have flown it a few times and it hasn't drifted off. So when people put that different GPS in, does that help prevent this problem? Or is there something else to do to prevent this problem going forward? Thank you again!
 
The GPS will not have any bearing on it. haha. Get it. Bearing. :)

The way to prevent this is to do the compass calibration in a wide open area. Outdoors, away from buildings, vehicles, power lines, metal fences, etc. And you also need to be powering on, and arming for takeoff away from those things. If you turn it on and take off by things like that which interfere with the compass, it causes gradual drift over time during flight.
 
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The GPS will not have any bearing on it. haha. Get it. Bearing. :)

The way to prevent this is to do the compass calibration in a wide open area. Outdoors, away from buildings, vehicles, power lines, metal fences, etc. And you also need to be powering on, and arming for takeoff away from those things. If you turn it on and take off by things like that which interfere with the compass, it causes gradual drift over time during flight.

Thanks!! Understood and I did the compass and level calibration in my front yard and I was like maybe 30 feet from my house. As far as powering up and arming? This begs the question, how far away from potential interference is it safe? Are we talking 20 feet or 200 feet? I also assume a typical house doesn't pose as much of a threat as if let's say you are standing next to an large office building or factory where there are many of electromagnetic devices in-use and wireless networks active? What about power lines? How far from those is safe and does it matter if it is a single underground or overhead powerline feeding a persons house in comparison to a large high voltage transmission power system nearby?
 
Here is an excerpt from the Ardupilot about common sources of magnetic interference and a basic guide how far away to be from such interference.


From: Community: — ArduPilot documentation

Magnetic Interference

Natural and Artificial Magnetic Anomalies Warning

Note: The following information has not been objectively tested to determine it’s impact on a vehicle’s compass accuracy in flight.

  1. Many things can distort the earth’s magnetic field in the area you are flying:
    • Steel framed or reinforced concrete buildings, bridges and roadways, iron pipes and culverts, high power electric lines, heavy equipment, trucks and automobiles, steel tanks, electric motors and even computers.
    • Flying between steel framed or reinforced high rise buildings will distort the magnetic field in addition to causing GPS multi-pathing.
  2. Safe distances for compass calibration
    • 6” (15 cm) minimum: Metal rim glasses, pen/pencil, metal watch band, pocket knife, metal zipper/buttons, belt buckle, batteries, binoculars, cell phone, keys, camera, camcorder, survey nails, metal tape measure.

    • 18” (50 cm) minimum: Clipboard, data collector, computer, GPS antenna, 2-way radio, hand gun, hatchet, cell phone case with magnetic closure.

    • 6 ft (2 m) minimum: Bicycle, fire hydrant, road signs, sewer cap or drain, steel pole, ATV, guy wire, magnets, chain-link fence, bar-wire fence, data collectors that use a magnet to hold the stylus.

    • 15 ft (5 m) minimum: Electrical box, small car/truck, powerline, building with concrete & steel.

    • 30 ft (10 m) minimum: Large truck, metal building, heavy machinery.
 

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