My drone went bonkers

[jwadsworthza]

So I guess that someone on the group will tell me that this is my fault, but here goes. Take off. Compass error on phone, exit GPS. Hmm RC shows GPS connectivity... Go figure the two don't speak. Land. Take off. ATTI mode again. Flying slowly the drone goes bonkers and flies off backwards. Does not respond to the RC. This is at 1m above the ground. Not in Sport mode, no nothing. I have to repair the Gimbal one of the rubbers pulled lose. Nose damaged. Blades toast. The front arm has damage to the leg. Going to repair but for crying out loud, what the hell is wrong with the drone. It has been fine for quite a while since I had to reflash firmware because it was causing me problems. I updated geo software and this is happening? I am convinced that I wasted a lot of time and money on DJI rubbish. They are not the best drone manufacturers, they are anything but.

 

[sar104]

You will need to post the flight log files if you want anyone to try to figure out what happened.

TXT logs: DJI Flight Log Viewer - Phantom Help

Mobile device DAT file: How to retrieve a V3.DAT from the tablet

That said - your description looks like a classic case of magnetic interference at the takeoff point. And it tried to warn you but you ignored it.

 

[jwadsworthza]

You will need to post the flight log files if you want anyone to try to figure out what happened.

TXT logs: DJI Flight Log Viewer - Phantom Help

Mobile device DAT file: How to retrieve a V3.DAT from the tablet

That said - your description looks like a classic case of magnetic interference at the takeoff point. And it tried to warn you but you ignored it.

I have flown in this area many times, never an issue. Having magnetic interference issues all of a sudden is quite impossible.

I will download and update the records.

 

[sar104]

I have flown in this area many times, never an issue. Having magnetic interference issues all of a sudden is quite impossible.

No - it really isn't impossible at all. Magnetic interference in this context is not an area phenomenon - it's typically a very local issue due to taking off from somewhere with ferromagnetic material present. It could be rebar in concrete or something as insignificant as a magnetized nail or screw on the ground under the aircraft.

 

[RayOZ]

1. GPS not the same as compass.
2. Maybe you were wearing a new smart watch? It's been known to cause interference.

 

[jwadsworthza]

No - it really isn't impossible at all. Magnetic interference in this context is not an area phenomenon - it's typically a very local issue due to taking off from somewhere with ferromagnetic material present. It could be rebar in concrete or something as insignificant as a magnetized nail or screw on the ground under the aircraft.

True, however I have lived in that area for years. From an open piece of ground to

No - it really isn't impossible at all. Magnetic interference in this context is not an area phenomenon - it's typically a very local issue due to taking off from somewhere with ferromagnetic material present. It could be rebar in concrete or something as insignificant as a magnetized nail or screw on the ground under the aircraft.

I saw this area being built over 30 years ago. There was nothing but a field back then and a piece of tarred road now. Having flow this area for 3 months, what happened today was completely out of the ordinary. While I was hovering, the drone starting drifting in ATTI mode. I tried gaining control, but nothing worked. The remote showed GPS, the phone an issue with the compass. Even in ATTI mode I should have full control, but the drone did nothing to respond, even when I tried countering its direction (in the right plane), the drone kept on moving and did a somersault. I have into the folder to look for the text file, there is nothing dated today. However in the software I see

1. GPS not the same as compass.
2. Maybe you were wearing a new smart watch? It's been known to cause interference.

True. GPS keeps the drone in place. ATTI mode is oh crap the drone lost signal yet again. The only smart thing about my watch is me. PULSAR Chronograph Titanium which would not present an interference. I would be horrified to think that anything magnetic on your body like a bracelet could bring the drone down. That being said, would not account for all the times I have flown with the watch on and nothing went wrong. Still does not account for a total RC disconnect from the drone. I still say and it will be very difficult for anyone to do convince me otherwise that the Mavic Pro is an overpriced low quality drone. Which I would never have wasted all my money on if I knew of 10 percent of the complaints I have read. Hell, if DJI manufacturered planes we would not have an overpopulation problem on earth. You would be expecting to hear daily a plane had gone down. Their service is putrid. Their staff very unhelpful. Our local post office which is almost always on strike is more helpful than them. The founder of DJI has simply lost touch with his customers if he ever did care about them.

 

[sar104]

True, however I have lived in that area for years. From an open piece of ground to

I saw this area being built over 30 years ago. There was nothing but a field back then and a piece of tarred road now. Having flow this area for 3 months, what happened today was completely out of the ordinary. While I was hovering, the drone starting drifting in ATTI mode. I tried gaining control, but nothing worked. The remote showed GPS, the phone an issue with the compass. Even in ATTI mode I should have full control, but the drone did nothing to respond, even when I tried countering its direction (in the right plane), the drone kept on moving and did a somersault. I have into the folder to look for the text file, there is nothing dated today. However in the software I see

True. GPS keeps the drone in place. ATTI mode is oh crap the drone lost signal yet again. The only smart thing about my watch is me. PULSAR Chronograph Titanium which would not present an interference. I would be horrified to think that anything magnetic on your body like a bracelet could bring the drone down. That being said, would not account for all the times I have flown with the watch on and nothing went wrong. Still does not account for a total RC disconnect from the drone. I still say and it will be very difficult for anyone to do convince me otherwise that the Mavic Pro is an overpriced low quality drone. Which I would never have wasted all my money on if I knew of 10 percent of the complaints I have read. ****, if DJI manufacturered planes we would not have an overpopulation problem on earth. You would be expecting to hear daily a plane had gone down. Their service is putrid. Their staff very unhelpful. Our local post office which is almost always on strike is more helpful than them. The founder of DJI has simply lost touch with his customers if he ever did care about them.

Are you going to post the log files, or is this just going to continue as pointless speculation?

 

[jwadsworthza]

Nothing pointless about it. I have uploaded the file.

 

[Simmo]

Hundreds of compass errors??!!
I dont get the slight increase in altitude, with a reduction in throttle near the end?
But it looks like it was responding? You gave 100% down throttle, and forced it to the ground??

 

[sar104]

Nothing pointless about it. I have uploaded the file.

Perhaps the wrong file? It does show a short flight, but no evidence of a crash in the pitch and roll data. In terms of the aircraft behavior, it was in P-GPS throughout, no ATTI mode. It was facing SW and flew forwards around 12 m, not backwards, under positive elevator command - the pitch tracks precisely with the elevator input:



The corresponding DAT file is FLY140.DAT if you want to look at that. Or do you have a different flight log for a flight that corresponds to the behavior that you described?

 

[jwadsworthza]

Hundreds of compass errors??!!
I dont get the slight increase in altitude, with a reduction in throttle near the end?
But it looks like it was responding? You gave 100% down throttle, and forced it to the ground??

It makes no sense to me either. I was moving the stick but the drone did not do anything in response. It was moving backwards at a weird titled angle. The flying time was just over a minute. So while yes I was moving the stick trying to get it to moving away from me it did not respond at all. I have strange video of a flight just before that one while it was acting erratically. Flying it 1m from the ground was to see how it responded after a restart. It made little difference. Just before this I did an update for Geo records. I even tested in beginners mode and this was unpleasant as well. This is all after an update.

 

[sar104]

Hundreds of compass errors??!!
I dont get the slight increase in altitude, with a reduction in throttle near the end?
But it looks like it was responding? You gave 100% down throttle, and forced it to the ground??View attachment 53932

I don't see anything strange about the vertical motion - it held vertical position until down throttle was held at the end to force it to land. It confirmed forced landing at 400.7 seconds and then descended.

 

[jwadsworthza]

It makes no sense to me either. I was moving the stick but the drone did not do anything in response. It was moving backwards at a weird titled angle. The flying time was just over a minute. So while yes I was moving the stick trying to get it to moving away from me it did not respond at all. I have strange video of a flight just before that one while it was acting erratically. Flying it 1m from the ground was to see how it responded after a restart. It made little difference. Just before this I did an update for Geo records. I even tested in beginners mode and this was unpleasant as well. This is all after an update.

Another comment. The drone was reversing. I pushed full throttle to try and slow down the rate of movement. I will check the drone later for any video footage.

 

[sar104]

Another comment. The drone was reversing. I pushed full throttle to try and slow down the rate of movement. I will check the drone later for any video footage.

It wasn't reversing in that log unless the compass was 180° out and the wind was blowing significantly to the SW, since the drone was pitched forwards. That's all possible, of course, but you will need to post FLY140.DAT from the mobile device to confirm that compass error. Do you recall in which direction the aircraft was facing at takeoff?

 

[Simmo]

sar104 I was refering to at around 395, a slight down throttle, but 100mm increase in height?

 

[sar104]

sar104 I was refering to at around 395, a slight down throttle, but 100mm increase in height?

10 cm? That's the digitization step of the data. The s-wave data didn't detect it either - it's not real.

 

[sar104]

10 cm? That's the digitization step of the data. The s-wave data didn't detect it either - it's not real.

To add to that - it ignored the slight down throttle because it was at landing height. It took one second of full down throttle, starting at 399.6 s, to force landing.

 

[Simmo]

Hey and also, the operator says he applied full throttle to slow movement, there was never any positive throttle applied.......

 

[sar104]

Hey and also, the operator says he applied full throttle to slow movement, there was never any positive throttle applied.......

There was tentative forward throttle throughout, which corresponds exactly to the pitch response of the aircraft. And the log indicates that the aircraft moved forwards (to the SW) in response.

 

[Simmo]

Ahh ok..., yes, Elevator, not throttle!