Hoverbear

We've already talked a bit about motors in our previous articles, in this article we'll talk more about motors than the quadcopter as a whole.

In our past articles we've explored some of the basics of the mechanics of Quadcopters. In this article we'll be doing something a bit different and discussing the algorithms behind how the Quadcopter keeps itself stable.

To do this we'll actually be inspecting some of the official Bitcraze Firmware and it's stabilizer.c implementation.

It's okay if you don't know C or understand what's going on in this file, that's part of the purpose of this article!

Most intelligent devices existing in the physical world, a quadcopter included, take input from sensors and act on them in some way, possibly producing an output.

Lately we've been playing with Quadcopters a lot, one of the key components of any copter is it's motors! I'll be writing about motors next, but before that I wanted to share some small, short Arduino 'labs' that you can do either on your own or with your cohort!

All of these 'labs' are as inexpensive as we could manage in terms of parts, with the exception of the Arduino.

So, in our earlier article we talked about Yaw a little but, but we didn't get into details. First, let's take a look at what yaw looks like under simple circumstances, then we'll explain the motion.

This post is less about the mechanics of the quadcopter and more to satisfy those curious about what exactly is on the board.

Here are links to the schematics and component placements:

• Component Placement - Top
• Component Placement - bottom
• Schematics

On the pictures below we'll use the schematic symbols as they are shortest.

Spinnning tens of thousands times a second, four rotors cut through the air with their propellors. Their motion lifts them in unison, for they are connected together. In the center of the apparatus sits a bank of sensors, processors, and a radio acting in concert to control the great flow of air passing over it.

Some ways away, perhaps near, perhaps far, its pilot watches over it. Whether by program or controller, they hold the fate of the airborne being in their hands.

Quadcopters are fascinating marriages of physics, electronics, aviation, and computer science that have only become popular in the last couple of years. Examining them allows us to explore a number of interesting topics.

But first, a bit of an introduction...