How does a Direct Drive Variable Pitch Multicopter Achieve Yaw? - RC Groups
Jun 19, 2012, 11:43 PM
Question

# How does a Direct Drive Variable Pitch Multicopter Achieve Yaw?

ASs stated, there seem to be several Direct Drive (Single Motor driving all props through gears/belts) Variable Pitch Multicopters, but i am confused as to how these obtain yaw motion.
I know that on independent drive multicopters, each motor can spin at a slightly different speed to achieve the desired yaw, but a multicopter with a single motor cannot achieve this through the same method.
Not sure how variable pitch could achieve a yawing motion either on a direct drive.

So, how does a Direct Drive Variable Pitch Multicopter Achieve Yaw?
 Jun 20, 2012, 12:20 AM Registered User more lift created by increasing pitch is the same as increasing rotor speed on a fixed pitch multicopter
 Jun 20, 2012, 12:58 AM F550 Hex, Blade mQX I know about the lift, and providing more lift in one side of the aircraft would provide pitch and roll, but still not yaw.
 Jun 20, 2012, 02:10 AM Registered User Increased pitch on one pair of rotors and decreased pitch on the other pair. This creates the torque difference to yaw the multicopter. Don't ask me how to control yaw at 0 pitch.
 Jun 20, 2012, 06:19 AM Suspended Account Well at 0 pitch with cp heli blades you're either on the ground or heading there fast
 Jun 20, 2012, 11:05 AM Registered User Stall turn?
Jun 20, 2012, 03:04 PM
Linux Compatible
Quote:
 Originally Posted by SGsoar more lift created by increasing pitch is the same as increasing rotor speed on a fixed pitch multicopter
This is it.

It's all about creating that resultant torque. There isn't anything intrinsic about the motor speed that would *require* a differential to create the torque needed to yaw.
 Jun 20, 2012, 03:11 PM Registered User The easiest way I have found is to use a V-Tail although I am not using it right now for variable pitch. Otherwise, it would require a sensor to detect when the pitch is positive or negative then adjust the motors' speed accordingly or on a tricopter, reverse the rotation angle..
 Jun 20, 2012, 03:28 PM Registered User P.S. IMO, there is little or no need to worry about Zero Pitch. If the the Pitch remains there for any length of time, the copter is going to drop like a rock. Now ask me how I know this. LOL