Thread: Crab drive steering
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Unread 03-09-2011, 19:59
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Aren Siekmeier Aren Siekmeier is offline
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Re: Crab drive steering
Quote:
Originally Posted by Ether View Post
The wheelbase and trackwidth do figure into the inverse kinematics.
When calculating the omega cross r term yes (for a unicorn drive, in which case you're already doing that math anyway, you just need to plug in a different r vector for wheel position), but for standard crab, you can drive in a straight line in any direction with all four motors at full speed with the wheels in the orientation I described. I haven't rigorously proven it, but my own intuition regarding the torque exerted by each wheel, it shouldn't be an issue.



Quote:
Originally Posted by Ether View Post
Not all optical encoders are incremental. There are absolute optical encoders.
Good to know. I've only ever seen/worked with incremental ones, and absolute clearly have their advantages. I still like mags better though . However, both have their strengths.