[Chris Hibner]

Continuous pots work pretty well, but there are two "gotcha's::

1) The pot can shift over time due to shaft slippage. Usually not that big of a deal, but keep an eye on it.

2) (Potentially BIG) There is a gap in the pot at the wrap-around point where the voltage will float. That will give you false position readings in the gap. The gap may seem insignificant at first, but it grows over time as the pot mechanically wears.

There are two ways to cure #2. The first is to wire in a pull-down resistor so the voltage doesn't float. The second method is to put the gap at an angle that you don't need to stop the motor, stop reading the pot near the gap, do a timed motor command to get through the gap, then start reading the pot again. You may consider doing both. We were using a continuous pot at Kettering and we somehow lost the pull-down resistor. We had trouble kicking for a few matches until we figured out what happened.

If you want to use a relative encoder, your cam actually makes that quite easy. Start each match by driving the kicker motor backward with a small enough PWM so you don't damage anything. Montior the rate of the encoder. Once the encoder stops moving, you know you hit the edge of your cam. Reset the encoder position and then start using the kicker as you normally would. By doing this, you will get a very accurate zero point of the encoder every match.