Draganfly DraganFlyer V Ti, Manual

21

How the Draganflyer Flies

continued

The Draganflyer has this speed logic built into the circuit board’s “chips” and the ratio of motor-
rotor speed is a design consideration of the machine.

The Stabilization System

Up to now, You’ve hopefully gotten a pretty good picture of just how the Draganflyer stays in the
air and remains under control. What you may not appreciate, is that without the Stabilization
System, no one could fly it! The Draganflyer’s motor-rotors and propellers are designed to turn at a
pre-determined RPM. Since nothing in this world is perfect, each motor is going to react to the same
voltage differently and each FET is going to react to the “trigger” voltage differently. While these
differences may be subtle, they are enough to make the Draganflyer nearly impossible to fly. So to
create a usable machine, a stabilization system is employed. This same principle applies to many of
the high-tech military aircraft such as the Stealth fighter.

In the case of the Draganflyer, the Stabilization System consists of some logic circuits and 3 of those
long cylindrical devices called piezo gyros. As I said before, one is mounted vertically on the verti-
cal circuit board, while the other two are mounted on the horizontal circuit board.

Of the two mounted on the horizontal circuit board, the left one is oriented in a front to back posi-
tion, while the right one has a left to right orientation.

If you haven’t guessed by now, they are mounted that way because of the 3-dimensional space that
flight itself occupies. These piezo gyros are used to detect movement in 3-dimensional space. That
is: Vertical and Horizontal or Up and Down flight as the receiver-mounted unit detects. Pitch
(Pointing nose down or up) as the left horizontal-mounted gyro detects, and Roll as the right hori-
zontal-mounted gyro detects.

Basically the piezo gyros are there to sense movement in any or all of 3-dimensional space and pro-
vide correctional motor control. Think of this as “dampening” the machine’s controls. Without this
dampening as I said previously, the machine would be nearly impossible to fly. This is simply due
to the speed at which the machine’s electronics are responding to the transmitter controls.
Essentially, when we give a command to the Draganflyer, as in a turn for example, to the right the
Piezo gyro circuit controls the speed at which the FET trigger responds and gives the motor-rotor
speed changes. What we end up with is a well-behaved machine that is possible to fly!

Generally speaking, the piezo gyros are configured to produce the opposite effect to what they’ve
sensed. That means that if the gyro senses the right side of the Draganflyer for example dropping,
it increases power to the right motor and decreases power to the left to compensate. All this is pro-
grammed to happen for you. Of course to perform a right turn, the electronic brain understands that
the stick commands from the transmitter override the built-in logic.

So how do the piezo gyros work? Piezo gyros actually harness 2 theories of Physics. One is the
piezoelectric effect and the other is the Coriolis effect.

How many of us have used the familiar outdoor gas grill? If yours has that little red pushbutton that
makes a snapping sound to produce a spark to ignite the gas, you’ve seen one example of the piezo-
electric effect.

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