Building a Quadcopter

Building a Quadcopter - Part 3

It's been another few weeks, and I'm back to building my quad.

Since I recently got my transmitter, it was time to start building the electronics of the quad. The AeroQuad project (link) is based on an Arduino for the flight control. It basically uses a 3-axis Gyro and a 3-axis Accelerometer for the flight sensing (other sensors such as Magnetometers and Barometers are also supported, but optional: more info). To connect these sensors, AeroQuad offers a 'shield' for the Arduino (What is a 'shield'?). The sensors need to be bought separately. There are 2 shields, AeroQuad Shield v2.0 (link) for Arduino Mega and AeroQuad Shield v1.9 (link) for Arduino Duemilanove. Since I already had an Arduino Mega, I ordered the 2.0 shield.

With the normal shipping method, it took about 3 weeks to arrive. The shield kit included the following,

AeroQuad Shield v2.0 Kit

The shield PCB
The Logic Level Converter
2 resistors (15K and 7.5K)
ULN2003 IC
3 LEDs
5 40 pin Headers
a nice AeroQuad sticker

The PCB has very good build quality. It's double sided and with 8mil track width.

The PCB

The LEDs that comes with it aren't the normal ones we use. They are 5V ones with built in resistors.

The 5V LEDs

The Level Converter takes care of converting the 5V logic signals to 3.3V logic and vise versa. It was quite smaller that I thought.

The LLC compared to an LED

Here's the shield with the components soldered. I decided to solder female headers to where the sensors might be, same for the LLC.


The soldered shield

The soldered shield - Bottom view

Here's the shield compared to the Arduino,

v2.0 Shield compared to Arduino Mega

Ready to be fitted :)

Ready to be fitted

The weight of the shield and the Arduino is about 75g. So, I think with the sensors, it should be less than 100g.

Now that the shield is finished, I will be ordering the sensors while start working on the frame.

Comments

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