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Unread 29-03-2010, 08:22
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Re: How Do mecanum wheels handle the bumps?

Quote:
Originally Posted by Drivencrazy View Post
When developing a design for this years robot our team questioned mecanum wheels' ability to push or pin and avoid being pushed or pinned.

In the end we decided to implement a crab drive. While slightly more complicated we felt that it would give us a pushing advantage.

My question is whether or not these asumptions were accurate and if so to what extent?

What other advantages or dissadvantages do mecanums have over some other forms of drive trains?
Mecanums notoriously lack "pushing power". The combination of a lower coefficient of static friction and the wheel's inherent inefficiency (Only ~71% of the output torque is transmitted in the direction of travel) would make your assumptions pretty accurate. Of course, prototyping for yourself is the best way to figure out to what extent these problems exist and whether or not you can live with them.

Mecanums generally try to avoid defense rather than overpowering it. This doesn't work particularly well in my opinion. Teams using mecanum should maximize their use in portions of the game with limited defensive interaction. For example, team 230 straddles the bump using mecanums in order to hang.
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