What are the props actually doing

[CarlJ]

You're all a bunch of heretics and should be burned as witches. That said, who wants to explain wind?

 

[ProfessorStein]

There once were four brothers; Boreas, Eurus, Notus and Zephyros...

 

[4wd]

It's a good question, how does varying the speed of props make it turn on the spot ?

 

[ProfessorStein]

It's a good question, how does varying the speed of props make it turn on the spot ?

In the case of yaw, I believe OI Photography is correct. The copter applies more speed to the props that have a particular direction of rotation, which negates the counter-rotating propellers, making the Phantom spin. It uses the very torque that most of the time the copter is fighting to counteract.

 

[ProfessorStein]

Here. As much as I hate to admit it... in this particular case, Wikipedia actually has a decent description of quadcopter flight control.

http://en.wikipedia.org/wiki/Quadrotor#Flight_control

 

[damoncooper]

I'll just say that this is the funnest thread I've read in a while. Carry on.

 

[Chris G]

Chuddly is correct, it is the pressure difference caused by the air moving faster over the top of the prop than it is underneath in the same way that a fixed wing produces lift. True, in a vacuum no air no lift but this is because there is no fluid in which to produce a pressure differential. As someone said earlier, pretty simple physics really.

 

[damoncooper]

Navigating to the top aerodynamics index page on that NASA site, there are some very cool topics there for the inquiring UAV piloting mind:

http://www.grc.nasa.gov/WWW/k-12/airplane/short.html

 

[chuddly]

I forgot about this thread! I like coming to a place and it doesnt seem odd all of us discussing crap like this LOL. My wife hears me talk about this stuff and she just says "your such a nerd" and goes on about her stuff LOL.