Quadcopter

20 May 2014

As a gift to myself for finishing grad school, I ordered all the parts I needed to make a quadcopter. Inspired by the amazing videos by TeamBlackSheep, David Windestål and others, the long term goal is to make a compact quad capable of transmitting video from an on-board camera in real time, and be piloted in first-person-view (FPV). I love the idea of goint to visit places inaccessible otherwise, of course without putting other in danger or invading their privacy.

After some initial tuning, I've got a flying quad ! Mounting a GoPro camera on it let me record the following video. I'm piloting both in line-of-sight and in FPV (first person view), which means transmitting the live video from the on board camera to LCD goggles.

Here's the bill of materials I needed to get flying.

HobbyKing Q450 V3 frame
RC-timer HP2212 1000kv motors (4x)
HobbyKing Blueseries 30A Electronic Speed Controller (4x)
HobbyKing 8x4.5 slow flight propellers (4x)
HobbyKing Multiwii 328p flight controller and Bluetooth module
HobbyKing Zippy Flightmax 4S 30C 5000mAh and 2800mAh LiPo batteries
Amazon Integy C23212 Lipo Voltage Checker/Warning Buzzer
HobbyKing Turnigy Accucel-6 battery charger
HobbyKing Turnigy 9X Radio Transmitter and Receiver
HobbyKing 1500mAh LiFe transmitter battery

Putting it together was quite simple, it's really like a DJI Flamewheel 450 kit, except with cheaper components, and there are tons of videos and manuals around the web. It's quite amazing to see it fly after only a couple hours spent on building it.

You'll notice that the top plate looks quite different from the other components, it's because I broke the original fiberglass plate in a crash and I had to cut a new one in an aluminum sheet. It's so convenient to have access to a waterjet, I quickly designed a replacement and the quad was flying again the next day ! I uploaded the files on the Thingiverse.

To fix some issues with the stability of the quad, I also had to flash the electronic speed controllers with a new firmware (latest SimonK hex file). It really improved the performance, the high pitch hissing noise that I used to hear disappeared completely, leaving only the melodious humming of the propellers (my understanding is that the new firmware uses a higher frequency pulsed width modulation, outside of the audible range). I used the usual USBavr programmer and followed these instructions for wiring. I flashed with the KKMulticopter Flashtool.