[Gr...] Posted August 2, 2018 Share Posted August 2, 2018 I cannot figure out what polar position is. In my mind, it should be a distance and an angle from the origin of the base alignment, but that is not the case. Attached are two pictures. One shows a point near a notch. The other shows a point on the side of the notch. The notch is centered nominally at 15 degrees ccw from +Z in the XZ plane. The outside circle has a radius of 5.24". I need the angle and the depth of the notch, so I thought to use polar coordinates. 1.) Highlight the space points. 2.) Resources -> Features representation... 3.) Mode dropdown to Modify 4.) Select Cyl., R, A, and H Note that R is vastly different from one to the other, and both are totally wrong. Same with the angle. And the Height. The points can run. 3d constructions from the center of the base alignment to each point show the correct A2 angle of about 15. The 2d Polar Distance characteristic shows the correct radius (using the base alignment features as datums). Can somebody please explain this?pic2.jpgpic1.jpg Link to comment Share on other sites More sharing options...
[An...] Posted August 2, 2018 Share Posted August 2, 2018 how big should the notch be? Can you measure the notch as an element circle or radius? Link to comment Share on other sites More sharing options...
[Te...] Posted August 2, 2018 Share Posted August 2, 2018 It looks like some kind of vectoring issue. The H value should be the same or at least close (Y axis). I would try playing with the vectors and see if you can get what you expect. Link to comment Share on other sites More sharing options...
[Te...] Posted August 2, 2018 Share Posted August 2, 2018 It is definitely a vector issue. Change the vector (using button shown in attachment) and then adjust the H, when the H moves in the correct direction you have the correct vector and the numbers should make sense then. If you adjust H and it moves in the wrong direction hit reset and try again. I am guessing it might be the X vector but not 100% sure.Capture3.JPG Link to comment Share on other sites More sharing options...
[Gr...] Posted August 2, 2018 Author Share Posted August 2, 2018 There are two of that image. Which one? I tried screwing with both, and the probing direction / location changed. That is a very bad thing. Those parts were correct. Also, what the heck is an X vector? Where do you see that? For additional info, refer to the attached picture. The outside diameter of the casting has a very loose tolerance. The notch is very small, and cleaned up (i.e. completely changed) with a hand file. The plan was to use points 1 and 2 for the polar radius relative to the base alignment near the notch. Then use that radius in a formula to drop down to the right height to get points on either side of the slot (3 and 4). Point 5 was to be in line with a symmetry point between 3 and 4, with a height relative to the found radius of the outside diameter of the casting. I can run the measurement plan with my setup casting, but I need formulas to adjust things for production. Also, knowing things about points seems like a good idea. Especially since the calypso documentation explanations are so amazingly terrible as a general rule of thumb.pic3.jpg Link to comment Share on other sites More sharing options...
[Gr...] Posted August 2, 2018 Author Share Posted August 2, 2018 In addition, I just changed the bolt pattern holes to polar, and they all give the correct radius (the diameter of the bolt pattern is 8.500), and height (Y value). However, the angle given is wrong. It is giving the angle cw from the +Z in the XZ plane, where the angle format would imply the angle should be ccw from the +X in the XZ plane. So three differences between my points and my centers: 1.) centers get the correct R 2.) centers get the correct Height 3.) centers at least get angles that are correct magnitudes from a different perspective. The centers of my points seemingly had no relationship to anything. Why the difference? I am even more confused than before!!!pic5.png Link to comment Share on other sites More sharing options...
[An...] Posted August 3, 2018 Share Posted August 3, 2018 Measure the notch as a circle, then form between the hole in +Z / X0 and the notch an "angle between elements"! You can calculate the depth of the notch with a formula! Link to comment Share on other sites More sharing options...
[An...] Posted August 3, 2018 Share Posted August 3, 2018 _ Link to comment Share on other sites More sharing options...
[Aa...] Posted August 3, 2018 Share Posted August 3, 2018 Gregory, Yes those angle illustrations are confusing. But regarding the screenshot in your most recent post, it is CCW from the +X direction. The angle is in the XY plane, not the XZ plane. Notice the small coordinate system centered on the circle in question. Link to comment Share on other sites More sharing options...
[Aa...] Posted August 3, 2018 Share Posted August 3, 2018 Sorry, Andreas, I think I just said what you were illustrating. Link to comment Share on other sites More sharing options...
[Gr...] Posted August 3, 2018 Author Share Posted August 3, 2018 Please sign in to view this quote. clear as mud Link to comment Share on other sites More sharing options...
[Gr...] Posted August 3, 2018 Author Share Posted August 3, 2018 Please sign in to view this quote. So what are the definitions? As in, R = fill in the definition Angle = fill in the definition Height = fill in the definition and so on Link to comment Share on other sites More sharing options...
[Aa...] Posted August 6, 2018 Share Posted August 6, 2018 Sorry, Gregory. I haven't done much with polar coordinates, so I didn't grasp your question. (I thought you were concerned with the start angle, not the angle in the coordinates of the center of the circle.) Andreas' point is that the "Space Axis" you select not only determines the orientation of the circle, but also determines the orientation of the axis of the cylindrical coordinate system. In keeping with the right-hand rule, the following apply when the default angle format is in use (the top option in "Positive orientation"): If the Space Axis is +Z, Height is the Z coordinate, R is the distance from the Z-axis, and Angle is the angle in XY, starting from the +X direction and moving towards the +Y direction. If the Space Axis is +Y, Height is the Y coordinate, R is the distance from the Y-axis, and Angle is the angle in ZX, starting from the +Z direction and moving towards the +X direction. If the Space Axis is +X, Height is the X coordinate, R is the distance from the X-axis, and Angle is the angle in YZ, starting from the +Y direction and moving towards the +Z direction. If the Space Axis is -Z, Height is the -Z coordinate, R is the distance from the Z-axis, and Angle is the angle in YX, starting from the +Y direction and moving towards the +X direction. If the Space Axis is -Y, Height is the -Y coordinate, R is the distance from the Y-axis, and Angle is the angle in XZ, starting from the +X direction and moving towards the +Z direction. If the Space Axis is -X, Height is the -X coordinate, R is the distance from the X-axis, and Angle is the angle in ZY, starting from the +Z direction and moving towards the +Y direction. Gregory, it looks like the issue is you have selected the +Y space axis, and you're expecting the behavior for the -Y space axis. Hope that makes the mud a little clearer. 😃 Link to comment Share on other sites More sharing options...
[Gr...] Posted August 10, 2018 Author Share Posted August 10, 2018 I am confused about something else now... On a similar casting, I am getting different numbers depending on how I get the characteristic? a 3d line from Circle 40 to the center of the base alignment (in this case Circle 1) gives me 0.0674 Polar position Angle_Circle 40 gives me 0.0674 the Angle check on the feature window gives me 0.0674 BUT... getActual("Circle 40").coordPolAngle in a result element gives me 0.0012 what is going on with this? EDIT: the answer is that result element is evil and changes things to radians without saying anything 0.0012*180/PI()=0.0012*57.2957795131=0.0674 Therefore, new question. Is there a setting somewhere that addresses this? Link to comment Share on other sites More sharing options...
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