Maximum flight altitude limit in mountain terrain?

[Keule]

A simple laser range finder pointing downwards should suffice.

Ahh, like a LiDAR device. They are costly and 'heavy'. You may look LiDAR for drones

 

[Lady Rover]

Like this. Already fairly small.

Maybe still a bit to large and expensive at the moment, but I'm hopeful we see this in the future:

Compact Diode Laser Rangefinders

And less range (=less power consumption) would suffice for our drones as we are not allowed to fly to high anyway.

Not sure to what range the current DJI downward pointing obstacle avoidance sensors could be made to work if DJI where to tackle this...

 

[Simmo]

I think @Lady Rover that the sensors are sonic, plus some vision/paralax sensors?? (Happy to be proven wrong of course).
No doubt sonic type sensors on boats for example can punch very deep under the wet stuff, but the power and size of the unit would be no doubt detrimental to a Mavic?
Your laser rangefinder idea certainly has merit in my book.....

 

[Lady Rover]

Sound travels much better in water than air. This is due to the higher density of water. So you need less power.
Still, bats use ultrasound too....

 

[Simmo]

Bats at short range though.... like the Mavic with a VPS good for upto 30mtrs from memory?

 

[Lady Rover]

Hmm, so still development homework for DJI.

 

[dannybgoode]

My bike computer and Garmin watch can tell me my altitude so why not a drone?

 

[Meta4]

My bike computer and Garmin watch can tell me my altitude so why not a drone?

But your watch and bike computer can't tell how high they are above the ground - only how high above sea level.
Just like most light aircraft.

 

[dannybgoode]

But your watch and bike computer can't tell how high they are above the ground - only how high above sea level.
Just like most light aircraft.

Another fair point and well made

 

[Duke846]

Ok bike probably uses gps altitude.
Don’t know about watch. I have a pressure sensitive watch that costs about 2k. The mavic would have to get a radar altimeter to get a accurate level above ground. (not going to happen). Aircraft use pressure altimeters that requires you to put in non standard pressure for the exact time you’re flying. I think what they are using is the best system.