# How is a drone moving forward?

How is a drone (quadcopter) moving forward? I'm working on a drone right now and I got into this problem.
At first I was thinking to speed up the motors on one side and slowing them down on the other side but I'm not sure if this will work.
So how is a drone moving forward?

A drone moves forward by trying to achieve a certain tilt from horizontal, where the tilt determined a given speed.

So, you might want to tell the copter to keep a 15 degree angle, which will push the copter forward...

Control loops within control loops - that's how all complex things work.

A quadcopter has 4 loops controlling height, X-angle, Y-angle and Z-angle (yaw). These directly
handle the 4 motors in various linear combination.

The input set points to these loops are used to handle flight. If the thing is remotely operated
from an RC transmitter you are doing the top level control loops controlling flight, if it is
autonomous the high level control loops compare position and velocity with the desired
flight course and adjust the tilts, yaw and height control inputs appropriately.

You will not be able to figure out quadcopter function from scratch with zero background. You have a lot of reading to do, understanding that the propellers spin in opposite directions and all work together in clever relationships to get pitch, yaw, and roll.

Same way a helicopter moves forward. Some helicopters have to tilt the nose down. More modern helicopters tilt the rotor instead of the body. It's called "PITCH" , (the other types of motion are called "ROLL" and "YAW). You should already know these basics before attempting to build a drone. This is RC helicopter/drone 101.

Yaw is the least intuitive for quadcopter. Helicopter is easy.
I still don't understand barrel rolling helicopters, though.

Cyclic and collective pitch control doesn't tilt the rotor, it controls how much lift is generated across the
disc and where it is generated - the blades will response to this, but that's not relevant to the dynamics
which is all about the pattern of lift force on each blade around the 360 sweep. In general rotor tilt is bad
and to be avoided as much as possible because too much tilt and you slice off the tail rotor and crash.

Quadcopters avoid all that complexity by distributing the lift between 4 individual rotors, and also neatly
avoids the requirement for a tail rotor.

It should work the same as a fixed wing: Pull back on the stick and straighten out at the bottom of the roll. I would think a lateral roll would be the same as fixed wing: push the aileron left or right and straighten it out when it’s level.

Rashemmel,

Isn't your quote...

If it's continuous it's the power line. And, you can usually feel the "vibration" in your (fingers/body, etc.) from the 50/60Hz power line frequency.

...from an entirely different thread?

OOPS !
I don’t know how that happened.

INTP:
Yaw is the least intuitive for quadcopter. Helicopter is easy.
I still don't understand barrel rolling helicopters, though.

heheheh..... that's definitely playing with fire....especially in a human pilot on-board helicopter. But, certainly spectacular.... barrel roll.

heheheh..... that's definitely playing with fire....especially in a human pilot on-board helicopter. But, certainly spectacular.... barrel roll.

RC helicopter acrobatics have no relation to full size helicopter capability.

I'm thinking that in order to have a real-life quad copter that can do a barrel roll, it needs to be made of titanium and the pilot needs to be able to survive 10G's while doing it.

I haven't seen any full size quadcopters

Pure Conjecture...

Let's see some videos of it flying , and doing barrel rolls...

Anyone can build a model and put it on display.

Does this count ?

What I had in mind

pwillard:
Pure Conjecture...

Nice! I'd be putting like 3 motors on each arm hehehe. As for flight time --- not sure how long we could stay up there for with batteries.

That's pretty impressive for full sized helicopters. I've never seen anything like that before.

INTP:
What I had in mind

What that guy did is awesome. Never seen anything like that before. Scary how it's done near built-up areas etc though, as that's the sort of thing we see in the news.... stunt heli loses control and hits a crowd etc.

Unbelievable and spectacular nevertheless. Thanks for showing those links!

As for OP's post..... yeah.... tilt the copter and apply enough power to maintain altitude, and start moving forward/backward etc.