Polar/Cylindrical Coordinates

[[To...]]

Here's something I always seem to have trouble working out. In the example below, let' say I want to report the width of the slot using a symmetry point. I add a pattern and I am able to get the 12 slot widths. However, I always get stuck when if I want to report the angle of each symmetry point relative to the center. If it were 12 circles in the pattern, I could just convert the coordinates of the circle from cartesian to polar/cylindrical, tick the Angle attribute of the feature and everything looks good. But if I do the same thing on the symmetry point, the angle/ radius and height values seem to be skewed relative to the symmetry point. And, the angle results are whacked, to say the least. If I do a best fit bore pattern of the 12 symmetry points, the polar angles work fine and that's all that really matters sometimes.

Can anyone explain how the polar/cylindrical coordinate system works when it comes to a symmetry point.

Also, what if you're using RDS-CAA and you want to measure this pattern of symmetry points with a stylus parallel to the top and perpendicular to the slots, A0 B-90, A30, B-90, A60 B-90, etc. Would I need PCM?
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[[Ri...]]

It's probably your projection axis.

Calypso tends to put features in strange axes.

Check the projection axis in the button where i (from i, j, k) is, and change it to the correct space axis.

In addition, you can recall your feature into an Angle Point. Features - Special Geometries - Angle Point. This will allow you to measure a feature to one alignment, but evaluate to another.

[[No...]]

I believe this behavior has to do with the fact that a symmetry point has no direction, not even a point vector. In such situations Calypso often falls back to seemingly strange defaults. There's some inner logic behind it, but usually not the one you'd need.

[[To...]]

The vector shown in the symmetry point is established by the first point. I don't think I have the option of changing this value without affecting the feature's strategy.

[[Me...]]

After converting to cylindrical coordinates, change the space axis to display the desired values.

[[To...]]

After converting to cylindrical values, it still shows I, J & K. However, changing the feature representation to Projected Angle, Space Axis is now visible. However, changing Space Axis to +Z, rotated the points the Z direction, as I expected.

[[Me...]]

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After converting to cylindrical coordinates, select the button next to the i unit vector. This will allow you to set the reference for the projected angle.

[[To...]]

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Aha! Thank you.