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Unread 15-02-2013, 09:57
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Ether Ether is offline
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Re: 4 Wheel Drive Too Much Traction

Quote:
Originally Posted by Taylor View Post
I agree that wider bases have less scrub, but never longer than wide?
Yes, under certain conditions wheelbase can be longer than trackwidth

For the robot pictured, if you make the following simplifying assumptions:
1) all four wheels identical and driven independently with the same torque

2) coefficient of friction of the wheels the same in X and Y directions

3) Center of Mass lies on the the longitudinal axis, somewhere aft of the geometric center of the 4 wheels
... then the analysis becomes straightforward:

http://www.chiefdelphi.com/forums/sh...ad.php?t=99089


JesseK's advice is good though:
Quote:
If the team doesn't understand the fundamentals of the forces of scrub in a skid steer drive train, then it's probably best they steer clear of longer wheel bases


Last edited by Ether : 15-02-2013 at 10:25.