Unable to land message

[winochef]

recently when using RTH the AC will get approximately 12”/18” above the landing pad and a message comes up- unable to safely land. Use manual controls to land. I use auto launch with precice landing point. The landing pad is 30” in diameter on cement driveway with nothing near it. No vehicles, house or metal objects. I thought it might be the metal rebar in the cement but it also did it when launching and landing on a composite deck.
Any ideas of reason this is happening??

 

[ac0j]

How close were you standing to the pad?

 

[winochef]

5-6 feet

 

[ac0j]

I have this happen now and then, I havent tested my theory, but I think when I am 10 to 15 feet away, it lands. the closer I get to the landing spot, the more I see this same message. Might be wort a try from farther away?

 

[winochef]

I’ll try to be further away to test your theory. That’s if the the crappy weather ever clears!!

 

[SATMAN]

There my be rebar steel reinforcement in the cement of the driveway messing up the compass. Anyway,,,, it's a thought.

 

[Qoncussion]

I have this happen now and then, I havent tested my theory, but I think when I am 10 to 15 feet away, it lands. the closer I get to the landing spot, the more I see this same message. Might be wort a try from farther away?

Sounds reasonable - in that, if Precision Landing is enabled, the Mavic uses the bottom sensors to take an image of the ground upon takeoff, then matches its landing position to the image upon return. If you were close to the craft at takeoff, but not when it returned to land (or vice versa), the ground images would not match. I don't use automated landing features, but would be interested to see how this plays out...

 

[dbyantis]

recently when using RTH the AC will get approximately 12”/18” above the landing pad and a message comes up- unable to safely land. Use manual controls to land. I use auto launch with precice landing point. The landing pad is 30” in diameter on cement driveway with nothing near it. No vehicles, house or metal objects. I thought it might be the metal rebar in the cement but it also did it when launching and landing on a composite deck.
Any ideas of reason this is happening??

If the pattern on the "landing pad" can be misinterpreted by the visual sensors and assume that the ground is not level, not sure if the visual sensors for landing are active at that height, but I have read about this behavior. Imagine a pattern that looks like a 3D block, "escher-ish" M.C. Escher - The Official Website.

 

[winochef]

There my be rebar steel reinforcement in the cement of the driveway messing up the compass. Anyway,,,, it's a thought.

I thought the same and moved too my deck and the same not suitable for landing message appears.

The landing pad is white with an orange bullseye and a large yellow H.