Best wheels for football field?

[MikLast]

Originally Posted by EricH

What's the wheelbase and track width? That's what would really make the difference, in terms of turning a 4WD tank.

Wheelbase: front axle to back axle (actually wheel point of contact with ground, but axle is usually close enough)

Track width: distance from left wheel to right wheel

If the wheelbase/trackwidth number is near 1, you're probably OK. If the wheelbase/trackwidth is significantly <1, no trouble at all (though I would consider adding a wheelie bar). If it's significantly >1, you will not want high-traction pneumatics on all 4 wheels, and may want to put some Colsons or slick-ish wheels on one end or on diagonal corners. Speaking of Colsons... that's another option to think about; I happen to know that they'll work in some fairly non-typical-FRC applications and keep coming back for more.

i will not have this for a few days, until then what else can you recommend?

[EricH]

Originally Posted by MikLast

i will not have this for a few days, until then what else can you recommend?

Not much--I haven't done much robot driving on anything but carpet. That being said, I've been on a team that built one to handle a very dusty surface.

Though... I would suggest checking ground clearance. You won't need much, but you'll need more than in FRC...

[GeeTwo]

We use pneumatic wheels for our t-shirt cannon. Our chassis is AM 31" nanotube (27.5" wheelbase, 6 wheel, with 1/8" drop) using Harbor Freight pneumatic wheels with the bearings removed and replaced with bushings for keyed shafts. Don't do this! The scrub is pretty bad, as we can't get the bushings in tight enough to get rid of the wobble. We're upgrading to AM pneumatic wheels and hubs this summer. Between the more solid hubs and slightly underpressuring the corner wheels, we figure we can make a much more nimble robot. Time will tell; if this doesn't do it, we may have to modify the center axle to lower it a bit more or replace the nanotube frame.

As far as pneumatic wheels, I definitely recommend them over solids; much less likely to tear up grass and race track surfaces due to the larger area of coverage.

[fargus111111111]

Our t-shirt shooter, seen here, http://www.chiefdelphi.com/media/photos/31867, is several years old but we are still running all the original wheels but one. They are solid, but wide and have a lot of rubber on them. After a recent upgrade to a four cim drive it runs with almost no problems on grass, pavement, and all floors.
Edit: I think they are old from am, but I'm not sure.

[MoistRobot]

832 uses 2 powered pneumatic wheels and 2 casters on their t-shirt cannon. No scrub, but going straight can be iffy at times. It's been working well for years.