[joeweber]

Originally Posted by Joe G.

What was the rationale behind the multiple rollers rather than a single traction wheel? It looks like it may have compromised your belt tension through inadequate wrap, and as you said, the friction from all the idlers wasn't doing you any favors.

How high were the traction rollers actuated off the ground when in mecanum mode? On similar systems, I've seen teams underestimate how high the traction wheels need to be raised to get them out of the carpet, which causes drag and slows the mecanums down. Plenty of teams manage very fast mecanum drives on four CIMs, so I feel like something else may have been in play.

In 2011 We used belts to drive our Mecanums, they worked great. We were thinking that if we just drop the belt to the ground we could get the traction and power that we needed by just droping it with penumatics. During design we found that it was't much more work to add rubber to our idler pully's that were on the ground. The 2011 bot moved quickly so we thought that this drive would move quickly also, like you say we under estimated the drag on the belt system. We adjusted the lift off the ground enough to just clear it. Durring our last competion we started to remove pulley's and gained speed each time but we could never reach the full speed until we removed all of them.
It's been fun trying to come up with designs different from main stream and has paid off with some awards but we usually work on them for a couple of years befor we put them on a robot, but this year we didn't wait and we should have. We have more Ideas but we are at a point were we want to start wining and are changing how we do things. Watch out the upcomming years we will rock.