Area and COA calculation on custom plane

[Mr. Simone Bigalli 0]

Hi,

 

I'm trying to evaluate the Area and COA of a curve drawn on a plane different from the principal ones. However, the two functions getArea() and getCOA() available on CAESES seems to work only on principal planes.

Is there any workaround?

 

Thank you very much.

 

Cheers.

Simone

[Mr. Bodo Hasubek 3]

Hi Simone,

 

as far as I know you can evaluate Area and COA of a curve only with respect to the principal planes and main axes.

 

In principle you now have two options:

 

1) Find a transformation that puts your (flat) curve into a principal plane. Use rotation and translation in a transformation chain to do that. Might be difficult though if you don't know the transformations.

    Using this approach it might be an option to create your curve in a principal plane, use your normal getArea() and getCoA() commands an find transformation to put your curve in the right position. You can then use the same transformation to transform your CoA point.

 

2) Make a surface out of your curve by connecting start and end point with a line. Then use .getAreaApproximation() on that surface for the area.

    Unfortunatly there is no CoA command for arbitrary surfaces, afaik. A work around would be to create a symmetrical solid around your surface. Then use .getCoG() on this flat solid. Since the solid is symmetrical around your surface CoG = CoA.

 

If anyone knows of simpler ways I would be glad to learn it too.

 

Regards,

Bodo

[Mr. Heinrich von Zadow 9]

Hi Simone (and Bodo),

 

I have wrapped everything into a small Feature for you...

 

Inputs are:

1. the curve you want to investigate

2. the principal plane you want to have it in

3. a line (in the same plane as your initial curve), i.e. simply connecting start and end, which will be aligned with the principal axis' abscissa

 

Outputs are the transformed curves, as well as the transformation and a reverse transformation in case you want to use this definition for other use cases...

 

 

 

Attached are both, the definition and a small testcase.

 

Cheers,

Heinrich

rotateToPrincipalAxis.fdf

testcase.fdb

[Mr. Heinrich von Zadow 9]

One small note on this: I used three points on the input curve (start, half length and end) to determine the plane in which the curve is positioned. If those points happen to be aligned in your case you will have to adjust the second point to something that works robust for your case...

[Ceyhan Erdem 14]

Hi All,

 

And also a simple case created for a case of a volute.

After having obtained the section, I move it to the principal plane and then calculate the necessary values.

 

Cheers

Ceyhan

section_CoA.fdb