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This tiny machine is fantastic, with a great stability. Look at the hands-off part of the video inside house!!

Very funny :-) Video:

Motors: 1811 2000Kv 10grams brushless motors

Props: standard 5x3

ESCs : Turnigy 6A

Batt : 2S610 Lipo

Weight (RTF) : 180grams

Again it´s a very cheap and easy setup. Because I use standard propellers I mounted left and right motors with some twist. I´d really love arduIMU flat hardware...

Look at the PPM output Rx, Is this a new 2.4Ghz receiver form DIYDrones?

No, it´s a "lighweight" (4.1grams) mix between Spektrum AR6110 Rx and Jordi´s PPM encoder. This is nice for DIY projects...

The code is improved from the old version. This one has the magnetometer integrated so now we don´t have drift

on yaw axis, better implementation for the D term on the PID controler (more responsive to user inputs), same safety improvements, fast ESCs update rate (166Hz), new PID tunning...

But this history had an interesting lesson for me... The prototype you see here are really the second one, the first one was a dissaster... (flys bad...)

Do you want to know the "small" difference between them? This:

For the first one, I use an U shaped aluminium arms to save some weight. Well this shape is very bad in torsion and generates a lot of vibrations. This vibrations saturate the gyros (our gyros are quite sensible on vibrations because the low internal resonant frecuency). You could see here a graph of the gyro output value vs Throttle and you can see clearly the effect...

I change the arms to the square shape (8x8mm) and problem gone!! Perfect stability... :-) Vibrations are our enemy (Lesson learned)

Here is the new source code: Quad1_mini_20.zip (see notes.txt inside)

Schematic (conections): Photo1 Photo2

More Photos: Photo1 Photo2 Photo3 Photo4 Photo5

Old post (first version) here

New ArduPilot Mega will be a perfect platform for Quad´s also, so stay tuned...

Jose.