639 doesn't actually use an active ball control mechanism, however our kicker is also quite different from the "average" team's kicker.
First of all, we placed memory foam over the majority of our kicking area, allowing us to herd balls easily without them running away the moment touch them.
Also, our kicker is pneumatic powered, but it is also a spinner, using a clutch against a dual-FP motor gearbox to allow us to slide out the actual kicker without the ramming of the motors. Behind the memory foam, our kicker gets to target speed, then when we are ready to kick the pneumatic pistons fire, releasing the motors so the kicker spins on momentum. Since it is constantly moving, we have a 1-2 second window where the ball can be kicked with a good amount of force after we tell it to actually kick, removing the major need to possess balls
Anyways, we only have .5 pounds to spare. How can we not use it on cool LEDs?
P.S. image of our kicker
here, and on the overall robot
here