[Jon Stratis]

The best sensor is one you have experience with.

Get a handful of encoders from USDigital and play around with them as a team. Learn how they work, and make sure you can make them work. That way, when the season comes, you'll be able to pick out the correct encoder for the correct job.

Do the same for potentiometers. Single turn and multiple turn, and as a team figure out what applications you would use each for.

For limit switches, get a few different sizes. Some applications, you might want something large (like sensing the ball in this year's game - the huge ones from the KoP were great for that). Other applications, you might want something smaller (like the smaller KoP ones). For other applications, you might want something even smaller (think minibot from 2011). Learning the best way to mount these and their performance characteristics can help the team during the build season.

Other than that, I would simply look at previous year's games, and see what sort of sensors were popular on robots. Get some of them and start playing!