[Ginto8]

We used a hall-effect sensor (put together by the team) to measure wheel speed -- two opposite-facing neodymium magnets in a bracket on the axle let us use the Counter class's getPeriod() (implemented in the cRIO's FPGA) to determine how fast it was spinning.

We also used IR bounce-back sensors (also team-constructed) for no-contact limit switching, similar to how aryker used a hall-effect sensor.

After our district competitions, we also added a string-potentiometer, which in our case we used to keep our tilter from going too high and pulling out our lead screws -- yes, there were mechanical alternatives, but we didn't want to risk dismantling the system on the first day of MAR champs. Also, our drivers ended up using it as an alignment system when our camera died (that is, never worked on the field).