What drivetrain style are you using?
 

I'm curious about the ratios of omni directional to tank drive this year. In the past, tank steering has been the standard for all but a handful of teams. This year's game seems to open a huge door for omni directional drive trains though. So what kind of drive train are you using?

Re: What drivetrain style are you using?
 

So far, the plan is six-wheeled tank, but with the middle set of wheels moved back 3.5 inches since the weight moved back so much for this year's design. Most of the components are on the back half of the robot with the giant trackball in front. We did consider, then tossed out mecanum drive (with regrets) since our apparatus is an elevator after a long history of arms, and the general consensus was try to keep the design to one new element per year.

Re: What drivetrain style are you using?
 

We planned at first to go with Ackermann, but once we got our previous year's 6WD working with Ackermann controls, we abandoned it for the traditional 6WD. So we have a 6WD that drives like an Ackermann...

Re: What drivetrain style are you using?
 

6 wheels.

This game will involve a great deal of turning and maneuvering to capture track balls.

It isn't as easy as "go straight turn left." :rolleyes:

Re: What drivetrain style are you using?
 

Our first two years were four-wheels, last year we ventured into the realm of six wheels, and it worked pretty well. THis year, we're going with rear drive wheels and casters in the front. We'll see how it works...

Re: What drivetrain style are you using?
 

Yikes, based on my experience, you hit the nail on teh head with 6WD... 2WD w/ casters has never worked out well for me

Re: What drivetrain style are you using?
 

Dualie traction wheels in the centers, dualie omni wheels on the corners, all driven.

I think a 6wd drivetrain is going to be pretty much the best bet in terms of weight/performance balance, and it's ability to hold on in a tight turn.

-q

Re: What drivetrain style are you using?
 

we are using a flying saucer...:p

Re: What drivetrain style are you using?
 

4 wheel drive high traction skid steer, driving 36" wide.

Excellent ability to hold our line in a high speed tight turn :D

Should be a fun competition, and I expect a very wide variety of robots there

Re: What drivetrain style are you using?
 

Just curious, has anyone had any experience with the holonomic style drive? (four omnis pointed at 45 degree angles to the robot sides) We were considering using it but ended up with standard tank and omnis in the back.

Re: What drivetrain style are you using?
 

Offset center wheel drive (center wheels pushed 1.5" forward)

The front and rear wheels are just unpowered slip wheels. We have used this setup twice before and it's incredibly maneuverable.

Re: What drivetrain style are you using?
 

we plan to use the a 6wd with the supershifters

Re: What drivetrain style are you using?
 

Walking isn't an option in the poll?? :eek:
Hmmph...

Oh well... guess I will have to go with "Other" in that case.

Re: What drivetrain style are you using?
 

we have 6 points of contact on the ground, the front and middle 2 are 2" IFI wheels and in the back we have ball casters. we should be able to turn really well in take mode.

Re: What drivetrain style are you using?
 

a very similar but yet much improved version of what we had last year.... you get to do the research lol. i'm excited for the improvements

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.

Re: What drivetrain style are you using?
 

Similar to years past, RUSH is using a 6-wheel configuration. Unlike last year we have gone down from the 8 in. AndyMarks to the 6 in. Also, instead of using omni-wheels to reduce friction when turning we have placed the center wheels 1/8th in. lower on the chassis.

Re: What drivetrain style are you using?
 

i think that a simple tank drive is gonna own this year.

Re: What drivetrain style are you using?
 

We (teem 1225) are using a front weal drive system with two casters on the back. it werks rely well.