Re: What drivetrain style are you using?
 

6 wheels with tank steering. This should make it easier to push the balls around, if need be, and also simply drive around well.

Re: What drivetrain style are you using?
 

We wanted to do a differential on ours, but alas we're trying so many new things this year we wanted to have a solid backup plan of just "driving around". It would be terrible for all of our new achievements to fail just because we made a mistake in our differential design. For this year, we're sticking with something that reliably works for us, and that's tank drive -- but with 2 omnis (possibly 4 if my CoM calculations were off :o ).

There's always the offseason though.

Re: What drivetrain style are you using?
 

mecanum we will se how much menuverability we will really get

Re: What drivetrain style are you using?
 

Ditto my friend. In 2005 we had that design. Our robot swung all over the place. You have no finite control.

Re: What drivetrain style are you using?
 

we are going with omni with 4 wheels at 45 degrees to the sides

Re: What drivetrain style are you using?
 

For our second bot ever, we are attempting a holonomic with casters on the corners to keep it stable when we use our lift. (how can casters keep anything stable one might ask....)

Re: What drivetrain style are you using?
 

Team 1189 is using a 6 WD design with the 8 in. Andy Marks performance wheels. We'll be using 4 CIM motors and super shifters to provide power.

Re: What drivetrain style are you using?
 

This year will see the Capitals running an improved version of last year's kitbot 6WD, reasons being:

a) We don't have the tooling or the manpower to get all uber-fancy
b) A judicious application of AndyMark products met our needs,
c) We liked what we saw last year.

Re: What drivetrain style are you using?
 

I agree with what others said about omni/caster wheels

omni and caster wheels are easy to push around. 6wd tank with AM 2 speeds for the win

Re: What drivetrain style are you using?
 

6WD with omniwheels at the corners, as we've been doing for a few years now.

http://www.chiefdelphi.com/media/photos/29748

Re: What drivetrain style are you using?
 

In 05 we only had 2 drive wheels in the middle and then we had 4 ball casters in the corners, it was a good design imo. We could turn on a dim and it just worked well.

Re: What drivetrain style are you using?
 

Last year for rack and roll we use 6 wheel drive but our front and rear wheels were omni wheels and our middle were the standard wheels we got. This year the team (14 people 10 of which whoom has never done anything like this before) voted on 4 wheel with two omni in the rear.

Re: What drivetrain style are you using?
 

We were going to try rack-and-pinion car style steering, but we figured that since we were so behind schedule we'd go back to tank steering. At least we still have the maneuverability necessary to align with and pick up a trackball...

Just out of curiosity (it's my first year at FIRST), what are the benefits of six-wheel drive train over four-wheel? And what's omni-drive?

Re: What drivetrain style are you using?
 

Omni-drive is the ability to go any direction without turning. Two classes are swerve (turn the wheels) and holonomic (non-turning wheels with rollers on them).

6WD vs 4WD is a little harder. 6WD doesn't bounce as much as a 4WD while turning. However, the exact benefits depend on the type of 6WD--dropped center, coplanar, and coplanar (omni-in-the-corners) have their own quirks and disadvantages, but all have their advantages.

Re: What drivetrain style are you using?
 

We usually go with 6wd, but decided that there wouldn't be enough contact this year to justify the weight.

2wd using Dewalt gearboxes on CIMs - in the center with 6" dia 2" wide IFI traction wheels. Ball transfers on the corners :D Basically a VERY fast modified version of our 2004 drivetrain.