Standard Motor Driver Schematic for FRC

[zcohen]

I applaud my students who want to learn how to make custom circuits or custom anything. While our team doesn't do it much yet, my understanding is the RoboRio allows for this a lot more than past controllers (I may be wrong, programming/controls is my weak spot)
That being said, these are the things that control a 120 pound robot going fast enough to hurt someone. They also control a huge amount of amperage. I trust my students a lot, but not when it could be something where a mistake could greatly injure someone else.
Further, out of all of our costs, motor controllers are pretty small. Yes, we did dump about $2k into the Talon SRX's when they came out, and I do understand thats a lot of money, but you can easily get away with a couple hundred and still have the Talon SRX and not a cheaper option like the REV one if the options the SRX delivers are important to you
One big thing you're missing too is these are reusable. That was largely a one time cost compared to motors/gearboxes/framing/etc which far exceeds 2k a year.

It would be great to save money in FIRST, but I dont think this is where to look. If money is an issue with a team, look at the structural components as a way to save money. Reusing simple small things like hex clamps, sprockets, or bearings adds up to far more than a few speed controllers.