[nyaculak]

In my experience, gyros are best used for relative angle measurements (i.e. turning 90 degrees relative to your current position). They tend to have a lot of "drift", meaning the angle will change from the true value over time. This doesn't matter if you only need a relative angle, but I wouldn't trust a gyro for an accurate absolute angle.

If you want to measure the angle of an apparatus on your robot, I recommend using some kind of angular potentiometer. The angle potentiometer will output a current between 0V and 5V. After you have the potentiometer set up, it's a matter of taking empirical measurements and creating a function to map the voltage returned to an actual angle. This is the method my team used last year to measure the angle of our disc launcher.