[Alan Anderson]

If I end up lead programmer for our team next year, I'm definitely going to put some fault-detection in the sensor system. During autonomous mode testing in our pit at Nationals, a stray fleck of metal shorted the 5v output of the RC, and the arm immediately went out of control. I did have a two-second "stall" timer in place at the time, but that was much too long to deal with the situation. (We managed to disable the 'bot before anything -- or anyone -- was damaged, though we needed to physically lift it to safely disengage the ball grabber from our pit structure. It could have been much worse.)

One standard way to detect sensor failure is to put a resistor in the line from power to the pot, and measure the voltage at their connection. If it goes high, a wire has likely broken. If it goes low, something is likely shorted to ground. The available range of sensor output voltage is reduced slightly, but the easy diagnostic check can be worth it.