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Unread 04-09-2011, 23:12
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Re: Crab drive steering

Quote:
Originally Posted by ajlapp View Post
Our algorithm was purely empirical. We set up a linear relationship between angle and "detuning" of the inside wheels.
I'd be curious to know how your empirically determined speed reduction compares to a rough analysis I just did. See attachments.

I assumed that the center of rotation of the vehicle will be halfway between the points A and B.

Multiply the "outer" wheel speed by the fraction at the end of the analysis to give the "inner" wheel speed. L is the vehicle wheelbase, W is the trackwidth, and Ø is the steering angle, clockwise from straight ahead.


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