Elliptical Patterns in Pro/E Wildfire 2 1

[TheDarnoc]

Hello,

I've been racking my brain with this one for some time now and I am able to do the brute force method of modeling each feature but I am sure there is a better way to do it. I am trying to pattern a set of holes along a curve but while maintaining the orientation of them relative to the curve. Imagine an ellipse on a piece of paper. Hold a pencil vertical at one point on the curve. Tilt ~45deg in any direction. Move the pencil (as defined by the angles in the XZ and YZ planes, Z is out of the paper plane and YZ is tangent to the curve) along the ellipse such that the YZ plane is always tangent to the ellipse.

I've tried a couple of things:

- Pattern on a line. Results in proper spacing, but does not rotate feature while doing it. It is good for vertical (Z-axis) holes in an XY plane.

- Pattern with a table. Given (r,theta) and a center, I still get the same result as with the line pattern.

- Pattern a set of datums and use existing points. I have already constructed a set of features without using patterns where the holes extrude into. I didn't pattern it because the manner in which I need to construct/merge the surfaces is complex and I didn't think I could execute. I can't project points onto surfaces and the points don't come from a pattern.

- Relations. I tried this but it didn't work because my curve isn't defined as a function. Haven't tried yet splitting it up into a couple of curves and just having it be an approximation.

Any thoughts? Is this fixed in later releases? Argh.

-Conrad

 

[mjcole]

There is a curve pattern option in Wildfire 4 and in WF3 I believe.

In Wildfire 2 the best option would be creating a Datum Point on curve to reference for your cut or other feature and then Pattern the point as you see fit to get your X,Y placement locations for your features. As long as your features reference the point and have orientation defined in the sketch you should be able to use a Reference Pattern. If you have multiple features you can group them together for a single reference pattern or pattern them each individually.

The Point on curve can be specified as ratio like .1 for tenth of curve length and this can be patterned easily. The problem is obtaining the XY locations you want. If a point is on the ellipse then it only needs an X or Y dimension because the other one is defined by the ellipse. To get the Tangent YZ plane you reffered to you can make a Datum Tangent to an Elliptical surface through a point on the curve. These features can be created and then hidden prior to patterning to reduce clutter. As long as your pattern contains references to the original point and a neutral plane you can keep parallel constraints other wise you can reference the Tangent plane or a perpendicular one and have the shape follow those so the orientation follows the ellipse.

Full Picture Link
In image shown above I patterned a point using ratio .05 starting with a .025 along curve ratio along elliptical curve. For an XY position pattern you'll need to dimension the X offset for each point and the Y value will be determined by ellipse. If you could attach a picture of your Brute Force model I'd be able to give better assistance.

Michael

 

[TheDarnoc]

Thanks Michael.

I spoke with a colleague of mine and he gave the same advice. I have a set of datums patterned, I managed to pattern the feature in general but I need to polish the model to make it work all the way around the curve -- I have a non-continuous surface. After that the holes should remedy themselves as long as I reference the first hole to the initial feature which is linked to the initial datum group of the initial pattern.

My faith has been restored with Pro/E.

-Conrad