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Unread 08-05-2015, 11:41
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Ginger Power Ginger Power is offline
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Re: Kiwi Drive Concept

Quote:
Originally Posted by GeeTwo View Post
I skipped the research when I realized that all of the square roots and trig functions canceled out, and the mapping was pretty straightforward. To map rotation about a point xr, yr at angular speed wr (measured in radians/second, with rotation from the positive x axis towards the positive y axis being a positive angular speed) to translation speed vx,vy and rotation w0:
w0 = wr
vx = w yr
vy = -w xr
you can use this same preliminary mapping to make a mecanum drive rotate around a desired point.

For conversion purposes, 1 radian per second is 30/pi ~ 9.55 rpm.



If you use mathematical conventions for your coordinate system (+x to the right, +y forward), and measure your rotations with the navigation convention of clockwise as viewed from above, your angular speeds will be reversed from this, and you will need to use:
w0 = wr
vx = -w yr
vy = w xr
Thanks a ton for all the information about kiwi drives! It has definitely influenced my plans moving forward!
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