Wiring it up for VEX.

Hello Everyone,

Over the past couple of months, I’ve heard a lot about wiring up the current control system to get it up and running with a VEX micro-controller.

Now, I’m super curious about this and I guess I have two primary questions.

  1. From my somewhat limited understanding of the electronics on a typical FRC robot, do I understand correctly that the micro-controller would only replace the digital sideCar and the cRio?

  2. From my very limited understanding of the driver station setup on a typical FRC robot, will we be able to use something other than the VEX joysticks to control the FRC bots? I guess what I’m asking is, is there a way to hook up a USB XBOX controller or some standard joysticks to the VEX microcontroller?

Much appreciated,
Sunny G.

My team built some off season robots using the VEX microcontroller platform. Personally, I found it to be very ungainly. There are several key limitations to this system, the largest being that you cannot (in any way that I know of) connect it to a computer and control it using a conventional dashboard program.

If you are interested in replacing the cRIO and digital sidecar with a different microcontroller and I/O board, I would recommend using an Arduino. They are very easy to program, and the native Arduino language interfaces well with the computer based Processing language.

What this translates into for you is a cheap (only $24 for the Arduino) and robust (fully compatible with all of the FIRST approved speed controllers, etc) microcontroller that will accept inputs from your Xbox controller.

We have yet to buy our second cRio. We have no regrets …

VEX has worked very well for testing our robots and writing quick code.

Here is the KitBot VEX code we constructed in week 1 of FIRST

VIDEO VEX-KitBot testing:

CODE:
http://code.google.com/p/discobots/source/browse/trunk/FIRST/2011/Protobot%20Vex%20Code.c

As for using an Arduino, I think its a low-cost alternative but the limited number of PWM and encoder inputs are not suitable to scale for a encoders on a KitBot