Hi,

some time ago I bought an Inertial Measurement Unit (IMU), to be precise I bought the MinIMU-9 developed by Pololu. (The link in case you need it) It’s small, cheap and provides gyro, accelerometer and compass readings, each in 3D. It is perfect for implementing an Attitude and Heading Reference System  (AHRS), very important if you want to control a RC plane, drone or other robots.

Luckyly, Pololu provides a complete software suite for the arduino, including the libraries for each sensor as well as a sample implementation for a AHRS, based on a Direction Cosine Matrix (DCM) approach. As I have close to no understanding of the theory behind this, I am very happy that the algorithm prints the roll, pitch, yaw angles to the serial interface ready for me to use!

No drifts, little noise (I need to take a close look there), simple as that!