Welcome to Chief Delphi
It's good to see that you and your teammates have found your way here to the forums.
I recommend you familiarize yourself with the search function here on the forums (spread the message to your teammates too!).
I also recommend checking out these two threads for some general info/advice on posting here on the forums:
http://www.chiefdelphi.com/forums/sh...ad.php?t=78869
http://www.chiefdelphi.com/forums/sh...ad.php?t=50532
The first one is a freebie. I believe the the device you are talking about is what is commonly referred to as a "pit cart" or "robot cart". A small number of teams have designed motorized carts, but most of us find high school students make good motors.
Here's a
good thread about carts.
Many pictures of carts can be found
here
Here's a
motorized cart
My personal opinion is that a motorized cart is a waste of time. A motorized cart will likely be much larger than a non-motorized one. There are also significant safety concerns that must be addressed with a motorized cart (see the description of the picture I posted above). If you're looking for an offseason project I think playing around with different drivetrains or designing a demo robot is more useful than a motorized cart.