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Unread 22-01-2014, 19:34
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Ether Ether is offline
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Re: CAD for Spiral Cam

Quote:
Originally Posted by chmorroni View Post
Ok. Thanks to all the replies. From what I am seeing, I should be able to use a polar coordinate system to define the curve, but I can't find a way to do that.

In playing around with the equation line tool a little bit, I have created an Archimedean spiral using the following data: x(t)=t*cos(t); y(t)=t*sin(t). I can't figure out how to modify those equations to fit my radii. Any suggestions?
For the parametric equations you gave, "t" is the radius of your spiral. so if you want the starting radius to be r1 and the ending radius to be r2, then vary "t" in your equations from t=r1 to t=r2.

For example, if your starting radius is r1=1.57 and your ending radius is r2=6.283 then your spiral would look like the attachment.

Why did you choose these particular equations, instead of, say, varying the radius of the spiral linearly with angle, like this?


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Last edited by Ether : 22-01-2014 at 19:39.
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