Strange behaviour - went into landing mode with 32% battery left.

[Peter]

DJI replaced my Spark last week, I have to say they were totally excellent, it took less than 2 weeks from leaving my house to receiving the replacement.

Second flight with the replacement last night and strangely, after about 9 minutes flight, it started auto landing with 32% battery left and no other warnings, it started a forced landing. I have the battery warning level set to 20%.

There's a disparity between IMU and VPS altitude, I was flying directly towards a setting sun at the time so I wonder if that was the cause although I still don't understand why it would start landing. I could still control the Spark and I wasn't far away so all ended well. It could have been quite different if the Spark was further away, over water, etc.

Here's the log file, it happened at 9:40.4: DJI Flight Log Viewer - PhantomHelp.com

Here's the video of when it happened, I turned the face away from the sun in case that stopped it:

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Any ideas?

 

[Dronason]

Maybe the answer would be in the DAT file in the Spark. It would have more info than the .TXT of the GO app but it is not that easy to interpret.
Just at start, before engine started, there was a message about "Unlock Authorization Zone", where you just at a limit of a NFZ ?

Most probably your VPS at 1 feet looks close to 0.3 m I have during a normal landing. It goes down to that value, wait a few seconds and then switch to mode VERT_LOW_LIMIT_LANDING and go down, land and stop motors automatically. At that time my throttle was fully down. But I would say that if you bring it that low level, it will not hover but land automatically (not 100% sure).


So some chance it comes from the VPS. Maybe the low light or sun was making your VPS thinking you were close to ground.
Maybe cleaning the VPS or any protective plastic film on it ?

 

[Peter]

Maybe the answer would be in the DAT file in the Spark. It would have more info than the .TXT of the GO app but it is not that easy to interpret.
Just at start, before engine started, there was a message about "Unlock Authorization Zone", where you just at a limit of a NFZ ?

Most probably your VPS at 1 feet looks close to 0.3 m I have during a normal landing. It goes down to that value, wait a few seconds and then switch to mode VERT_LOW_LIMIT_LANDING and go down, land and stop motors automatically. At that time my throttle was fully down. But I would say that if you bring it that low level, it will not hover but land automatically (not 100% sure).
View attachment 442

So some chance it comes from the VPS. Maybe the low light or sun was making your VPS thinking you were close to ground.
Maybe cleaning the VPS or any protective plastic film on it ?

Thanks so much Dronason.. I was fairly close to 'special area' NFZ, Brighton & Hove Albion football ground believe it not. I didn't have cellular data on, in airplane mode, so I couldn't override it but it let me fly nevertheless.



I don't have any protective film on the VPS and it is clean. I'll read up how to download the DAT file to see if that has any more clues.

Thanks again.

 

[Peter]

So since Monday, every flight is the same, she'll repeatedly go into forced landing which I can override by pushing up on the throttle. What will also happen is when rising, she will continue to rise unless I pull down on the throttle stick when she will go into hover and vice versa, she will continue to descend unless I push up on the throttle stick. When forced landing is activated, the VPS height in Go4 is red and around 1 foot so I suspect this to be a VPS problem. I chatted with support last night and they suggested refreshing the firmware and calibrating the IUM and compass, which I have done but not flown yet, will do soon.

I've loaded a flight from yesterday into Phatomhelp and the VPS height barely ever goes above 6 or 7feet and normally a lot less. I wondered if somebody would be kind enough to load up a flight log from their Spark just so I can see the behaviour of your Spark's VPS. Thanks.

DJI Flight Log Viewer - PhantomHelp.com

 

[Peter]

She does take pretty amazing panorama photos though!