[alicen]

my knowledge of mecanums:

Rack n Roll-
we used the 8" andymark mecanums, and our drivetrain/chassis only weighed about 60 pounds. we ended up with the compressor and a fairly heavy lift system as well, our overall weight tht year? 110 lbs. In competition, we didn't really get pushed around at all, and one team (with 4 or 6 WD- i don't remember) actually wanted us penalized for pinning them. what worked out was the manueverability of the mecanums, and we were also able to easily get to and climb other people's ramps.

Overdrive-
we used the 6" andymark mecanums, our drivetrain was lighter, of course, but the cost that year was the way the 6" mecanums are deisgned. We had the problem of, at championships, the metal holding the wheels together DUG into the carpet, adn kept us from turning at all. that year we also went with some gearboxes which ended up not being able to pull the robot sideways, but that's another story.

so, in my experience, mecanums have never really been a problem, as long as you've got your numbers right. this year, we've already gotten some 8" andymark mecanums (about $300 for all 4) and some 12:1 banebots gearboxes. our plan is to drop the mecanums down so that they hang below the chassis about the same distance that the kitbot would.

experience with swerve: i have absolutely none. i hear it's difficult to program, etc. my only thoughts are how well it would go up the ramp, but i really don't know about that.