[TubaMorg]

I see (no pun intended). You may want to look at what Greg said above to answer your question and work to implement alternative solutions. For example, though tracking a ball is rather difficult, locking on the target is fairly effective. So the next problem is to find the ball in autonomous. So you may not be able to see it, but your team has all the control on where to place balls before the game begins. In other words you will know how far the ball is from your starting position when you begin the match. If you can't track distance (no encoder or accelerometer), then you can try timing, which may be effective enough.
Good luck!