Wedgetop vs. Roughtop

[Cory]

Originally Posted by GRT808

If you do end up purchasing the belts from mcmaster carr and end up cutting them I suggest purchasing Blue Nitrile Rough Top belt. Based on previous posts and robots (254,294,973) I've heard it is a very robust material experiencing little wear throughout the season compare to the rough top AM sells. I'm not too sure if using a band saw to cut to size is a good method though (haven't tried it myself yet).

We've used blue nitrile. I know 233 ran all of 2008 on one set of wheels, but we never experienced the longevity that others did. It certainly didn't wear super fast, but it was not as good as some have advertised.

I would note that you can run the heck out of them and still have tread surface left, but it's basically smooth with dimples in it. We would lose all of our "nubs" and get to this point somewhat frequently.

[Chris is me]

Originally Posted by Cory

I would note that you can run the heck out of them and still have tread surface left, but it's basically smooth with dimples in it. We would lose all of our "nubs" and get to this point somewhat frequently.

Odd, we didn't get to that in our blue nitrile ever. By comparison, our normal roughtop wore "smooth with dimples" shortly after our second competition.

[jwfoss]

Because I am a huge fan of these, have you also considered Colson wheels?

http://www.robotmarketplace.com/prod...on_wheels.html

They have good wear properties, are pretty cheap, and are fairly "grippy" on the carpet as well. Plus I hear that there will be a COTS hub available for the 1.5" wide wheels this year.

[Tristan Lall]

I just found this, which summarizes tests conducted by Brecoflex for their timing belts in robot applications. It includes a chart of "friction" tests on carpet. They quote a coefficient of friction of up to 1.6 on carpet with smooth natural rubber.

Some have had success with using their belts as treads; others (1114/1503/1680 in 2006) haven't. Either way, they're an expensive option and require some dedicated engineering to do right.

[joek]

WELCOME
we find that traction is really not as effective as maneuverability, my team uses mechanum,and we run circles around tank drive teams.

[Grim Tuesday]

Originally Posted by joek

WELCOME
we find that traction is really not as effective as maneuverability, my team uses mechanum,and we run circles around tank drive teams.

And then us tank drive teams push you around.

[Ninja_Bait]

Originally Posted by joek

we find that traction is really not as effective as maneuverability, my team uses mechanum,and we run circles around tank drive teams.

I believe FRC has yet to see a mecanum robot actually driving circles around anything that moves. Video evidence, please!

[sgreco]

Originally Posted by joek

we find that traction is really not as effective as maneuverability, my team uses mechanum,and we run circles around tank drive teams.

I too would like some video evidence.


And just curious, are you trolling?

Around the CD community this is basically verbatim to what is typically regarded as the stereotypical troll post.

[cadandcookies]

Originally Posted by sgreco

And just curious, are you trolling?

Judging by the fact they won Lake Superior this year (traditionally a very defensive regional) I would doubt it.

If you'd like video proof, here's them playing in an exhibition against the winners of the Northern Lights Regional.

http://www.youtube.com/watch?v=efIed7UWGuw

Yes, that is them holding their own against Swartdogs (though I can't remember whether they have octocanum this year, and even if so, what wheels were on the ground) at 1:07. I would say that in my experience, their drive train is quite effective for what they use it for.

Also, they won that match.

Not to derail too much; keep just clarifying that point (if a little late).