Direct Drive Four Motor System

[Gary Dillard]

Collin:
Sorry I didn't see your post until just now.

S.P.A.M used 4 CIM's, 4 NBD gearboxes, and 4 "half tank treads" last year, and we loved it. We'll probably go with a similar design this year if it fits the game. It's the fastest we've ever assembled our chassis and drive system. The biggest drawback was the cost of 4 Breckoflex belts; they don't get much cheaper even though they are half the length.

side view

top view

Sorry, these are the best pictures I could find on our website. We drove the center sprocket on each tread with the output of the Dewalt gearboxes so we theoretically had 4 wheel control although we just ran them in pairs like a full tank tread. The treads are slightly angled down to the center to give the same "boogie wheel" effect that allows turning without dragging the treads.

We have always build our own custom gearboxes and other than the omniwheel drive system we built in '04 we have always used tank drive, but with 4 identical motors this was the first year we split them up that way. As has been posted, this system seemed more powerful than Fluffy. Credit of course goes to Gary and James Jones (James was a featured presenter on drive trains at the '04 FIRST conferences).

[CJO]

On a similar topic, our six wheel "direct" drive originally started out as a 4 motor/ 4 wheel design, which we then expanded to six wheels, and used driveline to connect all of the wheels. Upside, no chin/belts/tensioning . . . Downside? Weight, it was fairly heavy, but it worked well, and we were able to add encodes to get a good idea of where we were. Not quite as modular as a moter per wheel design, but we did it with just the 4 cims, and it did work quite well.

I would strongly encourage teams to try out more designs which use direct/line drives instead of chain/belt.

P.S. here is a picture of the front 4 wheels of our system: http://www.chiefdelphi.com/forums/sh...highlight=1097

[GMKlenklen]

Ok, there is all this talk of "tripping breakers" and such... So I ask what does it take to trip the stock breakers?
Also, because last year was my rookie year... I only have experience with one drive train... but I don't remember all these sorts of problems to do with it.
We had 2 stock trannys, with 2 cims per tranny. 4-wheel drive with the stock skyway wheels, i.e. your standard 4-cim 4-wheel drive slip steering set up.
We didn't ever trip anything... I pushed people around quite a bit, i flew down the field, and I always drove strait. Oh, and we never broke a chain.

Somehow we where amazingly lucky and evaded all of the aforementioned problems... if anyone knows how, I'd like to know!!!