Assistance with Mecanum Wheels

[HedlessChkn]

team 42 has used mecanum wheels in the past without suspension and a completely solid frame, the result was them bowing and rubbing against the frame the rest of the match... of corse this was also the result of us jumping entierly off of the 3 or so foot end ramp, instead of going down the ramp

(the ramp i speak of was the "aim high" start ramp)

[CollmandosGrl]

Thanks once again for your responses. I've read about every thread here on CD regarding mecanum wheels. In several instances people refer to some public code for the mecanum drive - and in several other threads when people ask the thread seems to die.

Is this a myth? Is there anyone out there gracious enough =) to share past mecanum drive code?
Thanks,
1466

[Jeff Pahl]

Last year we (1379) used the AM 8" wheels with the BaneBots 12:1 transmissions. We had 4 wheel independent suspension which worked great except the springs were a little softer than we would have liked. It's nice to be able to drive the robot over a 1x4 laying on the floor during demos with no problems. This year I understand they are going with a much stiffer suspension due to the cornering requirements of the game. The Mecanum drivetrain does not work very well unless all 4 wheels are in contact with the floor. Unless you are 110% sure that you will get no bending or warpage in your frame during the "vigorous interaction" between robots (or the far wall of the field that you can't quite tell how close you are to it from the driver's station in the opposite corner), make sure you have a way to ensure that you can keep the wheels on the floor in the later matches.

This post is where we got started from in terms of code: http://www.chiefdelphi.com/forums/sh...13&postcount=4

Good Luck!

[Urban Hawk]

I couldn't find the information exactly, i don't know where it went to. However mecanum wheels can hit high speeds, probably higher speeds then normal wheels since due to the rollers generate less friction while moving (the tend to produce more horizontal friction which allows them to turn like they do.) I know we hit between 10 - 15 mph with our robot last year and it had mecanum wheels. As for suspension i would say its a must regardless of what type of wheels you use if you don't want to wreck your robot like i did to ours last year due to no suspension.(destroyed entire floor, snapped the 120 pound tested fishing wire we were using for lift and it wrapped around the axle of one of our wheels and caused considerable damage. It wasn't a pretty sight. That and the time when we crashed into the cafeteria wall at full speed, knocked a few tiles of the wall and bent the axle.) Point is... regardless... put the suspension on!