Home point issues

[Dave A.]

I have recently noticed when I take off (straight up)and hover about 6 feet, the horizontal distance on the display starts increasing up to about 6 - 9 feet, without moving the Mavic at all horizontally. I even tried resetting the homepoint while hovering, and it did the same thing.
I am using 600 FW, and have re-calibrated everything.

Any thoughts??

Thanks Dave

 

[JLane]

Well firstly, resetting the home point after takeoff does not reset the 0 altitude. It just sets the new co-ordinates for the Home Point.

Secondly, I believe a few feet of variation in the baro/GPS altitude is probably quite normal. That's part of the reason these drones use sonar sensors to measure ground clearance when low enough (within 13m). You'll hopefully find that the VPS height reading does not fluctuate much while the Mavic is in a stable hover.

 

[Dave A.]

Well firstly, resetting the home point after takeoff does not reset the 0 altitude. It just sets the new co-ordinates for the Home Point.

Secondly, I believe a few feet of variation in the baro/GPS altitude is probably quite normal. That's part of the reason these drones use sonar sensors to measure ground clearance when low enough (within 13m). You'll hopefully find that the VPS height reading does not fluctuate much while the Mavic is in a stable hover.

Sorry I wasn't clear in my post. It isn't the altitude that is changing while hovering, it is the distance value on the controller that creeps up to 6 - 9 feet.

 

[JLane]

Sorry I wasn't clear in my post. It isn't the altitude that is changing while hovering, it is the distance value on the controller that creeps up to 6 - 9 feet.

Oops. I must have misread your first post. Now I'm not really sure what might be the cause. It's possible that's just due to normal GPS accuracy. How many satellites are you getting when you observe this? I must admit I don't think I've ever watched my distance reading closely enough to know if this is normal.

 

[HFMan]

Normal- GPS position is subject to variation depending on the calculated HDOP (horizontal dilution of precision) of the receiver- basically the geometry is not ideal to always pinpoint your position within 1-2 meters. Different days, different signal quality, different location- all produce varied positional accuracy.