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Unread 07-05-2011, 17:36
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Ether Ether is offline
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Re: Offseason Project: Holonomic Kiwi Drive Robot

Quote:
Originally Posted by MentorOfSteel View Post
if you allow discontinuous steering angles the associated infinite steering velocities then the crab drive is omnidirectional. But this may be where we reach an amiable impasse, because I do not allow infinite velocities in my kinematic analysis.
The steerable-wheel vehicle requires discontinuous steering angles only if you allow discontinuous vehicle commands.

But if you allow discontinuous vehicle commands, then the mecanum requires infinite wheel speed accelerations (instantaneous changes in wheel speed). So I don't see a bright-line difference between the two; they both sink or swim together. Hey, we can agree to disagree; vive la difference :-)

Quote:
Thanks, by the way, for pointing out your papers on the subject. They will come in handy if I ever convince my students to attempt and omnidirectional (or pseudo-omnidirectional ) chassis.
If your students are showing an interest in swerve drive, they might like to see a simple demo spreadsheet I put together which graphically shows the speed and steering angle of each of the 4 wheels for any given set of Xdot, Ydot, THETAdot vehicle commands. Look for the file "2011-05-07 swerve calculator" at this link.



Last edited by Ether : 07-05-2011 at 18:38.