[patrickrd]

On Cornell's robocup team we use a gyro for local feedback on the robots. There is a camera on top of our "soccer field" that takes photos of the field and sends information to each robot about where it is and where all the friendlies, opponents, and ball are. However, the information is time-delayed, thus it is slightly out of date. To make a long story short, the gyro helps the robot determine exactly what angle it is facing, since the vision data is outdated. Equally important, it also is used to make sure the robot is achieving the commanded rotational velocity.

An application to FIRST will give you much less satisfactory results, since once the match starts, the gyros and accelerometers are the only thing telling your robot how far it's gone and in what direction. These sensors only give you accelerations, not distances, so you need to integrate twice to get where your position is at a given time. The sensors have error and uncertainty (noise), and since you are integrating twice, the error accumulates to the second power with time. Based on my experience, it is still worth it. With JUST a rate gyro for feedback I've seen a robot move forward, do a complicated maneuver, and return back 5 seconds later to the exact place it started. Calibration and good use of the feedback (how to correct the position once the feedback tells the robot it is going off course) will be key to success.

Good luck,
Patrick