A few years ago (2010), just when the Quadcopter or drones were starting to rise, I decided to create an Open Source Quadcopter, as part of my robotics and automation passion. However, my economical situation at the moment didn't allow me to buy some of the for the moment expensive sensors and tools to build the whole thing.
Even if by the time I didn't finish the project, I did enjoy thought so much playing with the Kalman filters and the PIDs with a microcontroller and Matlab. Making a rudimentary PCB for the gyro and accelerometers was not that fun, due to the calibration and isolation from vibrations of both sensors to work well.
Anyway, finally, after some years... I finished the Quadruino. The hardware is mostly bought on the internet, because I don't want to rediscover the wheel again. I played already once with the estimators and the low level electronics, now I would like to focus on high level development for this new framework to work with.
Yesterday was the second, but first official flight. Something went wrong with the quad after some minutes of flight and due to some instability, I could not hold it in the air and it fell from something like 10 meters to the ground, damaging one of the arms on the crash. Soon I will migrate the electronics to a better frame, with better isolation from the vibrations of the rotors.
Some pics from yesterday: