Min altitude

Hayabusa · Apr 9, 2018

i don’t think there is an option but would like to able to set a minimum altitude. I do a lot of water flying and always concerned about it going to low. Would like to be able to set to say 5’ above water and know that even if I pushed it down it would not go lower than the 5’. I find it difficult when flying low, adjusting yaw, adjusting gimbal, etc... I’m busy watching screen for best shot and afraid I could slowly drop in.
I think it could be a cool option. Something you could enable/disable quickly.
Mike

Kilrah · Apr 10, 2018

Precision is not good enough to do that. a 5ft drift of the altitude measurement is common.

The bottom sensors can measure that more precisely but not over water...

Afremont · Apr 10, 2018

The ultrasonic sensor shouldn't have any trouble detecting water surface. Seems like that should keep it from hitting the water, but I don't know if they are active all the time, or just during landing. I believe that the clearance" number on the controller is what they are measuring.

William Stinessen · Apr 14, 2018

I recently experienced my MP trying to ditch flying abt 2 meters over very shallow water, as it probably saw the seabed abt 1 meter below the surface and tried to regain altitude. Fortunately I was prepared as I have read of similar experiences at this forum. All sensors were active.

Kilrah · Apr 14, 2018

Afremont said:
The ultrasonic sensor shouldn't have any trouble detecting water surface.

Ultrasonic and visual are combined. They are known to have trouble with it and disabling them is recommended over water. Can be the constantly varying angle and movement of the water surface.

Hayabusa · Apr 14, 2018

This is why I brought up a min height. If I had it set for no lower that 4’ then wouldn’t have to worry (as much) about it dropping down. Yes, if a big downward gust hit it but for the most part you could focus on flying and “focusing”.
Mike

Afremont · Apr 14, 2018

Kilrah said:
Ultrasonic and visual are combined. They are known to have trouble with it and disabling them is recommended over water. Can be the constantly varying angle and movement of the water surface.

I've read that the Mavic will attempt to land on water because it doesn't see it as water, but the ultrasonic sensor should absolutely detect it during flying and maintain a clearance above it. I haven't tried it, but it seems that it shouldn't treat water any different than ground when flying.

Edit:. Now, if the bird will fly into the ground without hesitation, then it certainly would fly into the water as well.