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Unread 29-03-2010, 11:41
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Ether Ether is offline
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Re: How Do mecanum wheels handle the bumps?

Quote:
Originally Posted by Chris is me View Post
My post assumes the rollers of a mecanum wheel spin.

If they don't, the number is greater than 71%, but then you don't have a mecanum wheel anymore, at least one as efficient in any other direction.
Hi Chris,

My reply to your post also assumes we are talking about mecanum wheels with rollers which are free to spin. Whether or not they actually spin in a given scenario is a different question.

For example, consider the following thought experiment:

There are two identical robots, RobotA and RobotB, which are absolutely identical in every detail except that RobotA has mecanum wheels and RobotB has standard wheels. The tread on RobotB's standard wheels is the same material as the rollers on RobotA's mecanum wheels. The standard wheels have the same effective diameter as the mecanum wheels.

RobotA and RobotB are each facing a brick wall, and there is a load cell on the front of each robot to measure how hard it is pushing on the wall. Each robot is given a slowly increasing identical forward command.

I claim the following happens:

- Up to a certain point, both robots push with exactly the same force. There is no 71% factor involved.

- If the motors are sufficiently powerful, a point will be reached where the wheels start to slip. RobotA, with the mecanum wheels, will reach this point before RobotB, with the standard wheels.



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