Attitude calculation on the NXT using a 6DOF IMU sensor

This clips shows how accurate a IMU sensor can be. An IMU sensor combines a 3 axis gyro and a 3 axis accelerometer. The signals from both sensors are combined using a nonlinear complementary filter to get an output signal that has low noise and is drift free. (Well actually it is only drift free over 2 axis. It still drifts over the Z-axis.)
This home made sensor will show a blue light when it is horizontal using a 0.5 degrees margin. Otherwise the light will turn red.

[LEGOMindstormsRobots]

How does your sensor compare to the dIMU sensor from Dexter Industries?