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How are A1 and A2 determined


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I'm trying to figure out how to interpret the angles A1 and A2. I know they represent rotation angles, but the behavior I'm seeing while tinkering with a theoretical 3D line starting with the +Z direction is not making sense to me. I start by giving the 3D line some length by setting "Depth"=3. Then, I rotate it about the Y-Axis by setting "A1 X/Z"=45, and I see the line pointing halfway between the Z and X axes, as I expect, then, I try rotating it about the X-Axis by setting "A2 Y/Z"=80, and it looks like the first angle has been forgotten.The line is now in the Y/Z plane, 10 degrees up from the +Y direction. Is this just a glitch in the visualization. Should these be interpreted as consecutive rotations? Intrinsic or Extrinsic?171_ab6ba6a09681c47fbacce1d318eb1122.jpg
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Thanks for posting that, @Dustin. That seems to indicate that A1 and A2 are the angles between the Feature's "Space Axis" and the feature as projected onto the coordinate planes containing the feature's "Space Axis". Is there a reliable way to determine, based on the "Space Axis" which projected angle will be A1 and which will be A2?
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only if A1 and A2 are less than 45 degrees.
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Maybe you can access it the old fashion way instead of using my link? Guide attached.
822_e5516c91c62e258803b66ac6962686d7.pdf
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My apologies, I thought the "Projections" section of the overall eLearning package was a free module but I was mistaken.

In short to interpret A1 A2 projections angles follow these 3 steps.
1. Note the last letter in each pair (X/Z), (Y/Z), etc. The letter will be the same for both the A1 and A2 and the Space Axis of the feature.
2. This is the direction the feature axis primarily (most closely) points towards.
3. The feature then tilts towards the first letter by the value of the projection angle.

The reason there are two angles is it takes both A1 and A2 to fully describe the feature's orientation in relation to its space axis. A cylinder's center axis, a plane's normal vector, etc. Hope this helps.
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I was taught way back in UMESS 300 days that:

The positive end of the second axis letter is tilted towards the positive end of the first axis letter if the angle is positive.

The positive end of the second axis is tilted towards the negative end of the first axis letter if the angle is negative.

Hasn't failed me yet
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