Altitude Issues

[LowFlyingSpark]

I posted this on the official DJI Spark forum as well, but haven't gotten a ton of traction. Apologies if you've already seen this there...

I've noticed that the altitude doesn't seem accurate beyond 20 feet or so, it reverts to ~3 feet no matter how high the RC is. I haven't had to let the AC RTH yet on it's own, but am worried that the issue with the altitude might make it just fly straight up. Today I also got an "Ultrasonic Sensor Error" and brought it back, before that I was flying just over some fairly tall trees and the altitude showed ~3ft. After the "Ultrasonic Sensor Error" the Altitude jumped from ~3 feet to ~50 feet and stays there until I bring it back to land (did so immediately after the error). When I look at the flight log it shows "IMU Altitude" ~50 feet. I think the AC must be at least 150 feet in the air, so none of this makes sense. I made sure the bottom was clean and have looked back at old logs and see that the first few flights had no problems. Any advice on ideas on how to get an accurate altitude?

I'm not using an OGT Cable, using Android, Samsung Galaxy S7 Edge, Latest version of the app.

DJI Flight Log Viewer - PhantomHelp.com

Edited to include:
I'm not using an OGT Cable, using Android, Samsung Galaxy S7 Edge, Latest version of the app.

 

[aviscomi]

Are you using an OTG cable?

 

[LowFlyingSpark]

Sorry, I should have included that - edited original post to include. I'm not using an OGT Cable, using Android, Samsung Galaxy S7 Edge, Latest version of the app.

 

[aviscomi]

Sorry, I should have included that - edited original post to include. I'm not using an OGT Cable, using Android, Samsung Galaxy S7 Edge, Latest version of the app.

Looks like you have a problem. If it were me I would NOT be flying this device.


Home Point recorded. Return-to-Home Altitude:328FT

 

[LowFlyingSpark]

I've got the shipping label ready to send it in, just want to make sure I'm not missing anything obvious. I've tried resetting the firmware, recalibrating IMU, cleaning sensors. It flies ok, it's stable, but I think in a RTH scenario it would just keep climbing.

Would 328FT be the height I'm at when I take off (i.e. my physical elevation above sea level)?

 

[Zookeeper]

it might be that the ultrasonics got a sniff of the treetops and reported back that altitude but all other sensors were telling spark it was much higher. It may have basically been unable to reconcile the differences and consequently reported inaccurate information..

 

[aviscomi]

I've got the shipping label ready to send it in, just want to make sure I'm not missing anything obvious. I've tried resetting the firmware, recalibrating IMU, cleaning sensors. It flies ok, it's stable, but I think in a RTH scenario it would just keep climbing.

Would 328FT be the height I'm at when I take off (i.e. my physical elevation above sea level)?

Something is definitely wrong with the VPS

 

[aviscomi]

it might be that the ultrasonics got a sniff of the treetops and reported back that altitude but all other sensors were telling spark it was much higher. It may have basically been unable to reconcile the differences and consequently reported inaccurate information..

Nah...it was screwed up before he even got 2 feet off the ground

 

[LowFlyingSpark]

Yes, calibrated the IMU and tested it again. It went to 3ft and kept climbing... I landed it when it got to ~25 feet and it's been parked since...

 

[DesertWindAero]

Download the KML and look at it with Google Earth. Definitely, something weird going on.

 

[aviscomi]

I more "long shot" do you have a lens hood or landing gear on this Spark?

 

[LowFlyingSpark]

Nothing at all on the spark. Not even the prop guards.

 

[aviscomi]

Google Earth

 

[LowFlyingSpark]

Download the KML and look at it with Google Earth. Definitely, something weird going on.

I loaded the KML file to google earth but not exactly sure what I'm looking for. Interesting that the Spark path seems to disappear into the trees. I can assure you it was above the treeline.

 

[aviscomi]

I loaded the KML file to google earth but not exactly sure what I'm looking for. Interesting that the Spark path seems to disappear into the trees. I can assure you it was above the treeline.

Yeah, that's because the IMU reading was -40 feet...LOL

 

[Lastrexking]

Check out this guys log Near Fly Away!! Please help! @andy_drew

His VPS is a million miles from the altitude the imu is giving.

I think DJI need to look at this.

 

[LowFlyingSpark]

I sent mine in today. I'll post an update once I hear from DJI.

 

[u814me]

I would say you should try a short flight test, open field area with no obstructions and try RTH.

 

[Anthony Geiger]

Reset IMU!

 

[HoboDan]

That’s scary.. But on the bright side, you live in a beautiful area.