Simmetry Plane for PolyNurbs wrap structures

Unknown

Hi,

I'm modeling polinurbs over the result of a stiffness optimization on a pedal. I set up the simmetry costraint before running the analysis since of course the pedal needs to have a simmetric shape considering its medium plane and the results came out simmetric as expected.

Once I move to Polinurbs tho there's no way to set a similar costraint so while I'm wrapping the main body of the pedal, facets of the Wrap tool (the ones in black that you drag along the optimized body, to be clear) are not always perfectly normal to the simmetry plane therefore resulting in an asimmetric final geometry to export.

I'd have to cut in half the final geometry, eliminate one of the two halves and mirror the second but this looks rude to me and also quite difficult to do without loosing properties or resulting in an error. 

I'd be very glad to have a suggestion regarding this topic

Thank you very much 

Thomas Quenaon_21507

Hi,

This is a common situation when rebuilding a symmetric optimization. To do this, I suggest you to create a cut view on your result at the symmetry plane:

 

With this you will only work on half of your results. You can then rebuild your geometry using polynurbs tools, but be careful, your polynurbs should not cross the green plane.

After that, you can do a mirror on your poynurbs and you'll use the bridge tool to merge both symmetric parts of your geometry:

 

BR-

Thomas

Unknown

Thomas Quenaon_21507 said:

Hi,

This is a common situation when rebuilding a symmetric optimization. To do this, I suggest you to create a cut view on your result at the symmetry plane:

 

With this you will only work on half of your results. You can then rebuild your geometry using polynurbs tools, but be careful, your polynurbs should not cross the green plane.

After that, you can do a mirror on your poynurbs and you'll use the bridge tool to merge both symmetric parts of your geometry:

 

BR-

Thomas

Hi Thomas,

first of all thank you very much for your fast and very complete answer.

I've already seen this method online, probably in one of Altair's tutorials.

My problem is that the section plane cuts the part on almost its whole lenght so I'd have to connect a lot of cages. Moreover as you said when you "touch" the green plane while wrapping, it creates some strange problems like green lines from the plan itself taking straight line to the infinite or things like that.

Having to design a part like a lever or a pedal pretty much forces the result of the optimization to have a long main simmetrical body and therefore the long cutting interface to connect after.

How would you suggest me to proceed? Trying to ignore the green lines and keep on with this method of is there any alternative?

 

Thomas Quenaon_21507

One other solution could be to rebuild the geometry of the whole part and then you cut the part along your symmetry plane, you choose the side you want to keep and from this you do a miror + Combine.

BR-

Thomas

Unknown

Thomas Quenaon_21507 said:

One other solution could be to rebuild the geometry of the whole part and then you cut the part along your symmetry plane, you choose the side you want to keep and from this you do a miror + Combine.

BR-

Thomas

Tried that too in previous versions but it invalidated the Polynurbs so I could edit them later and often also caused problems while combining. I'll use this procedure if possible after I solved another problem that came up recently, the App crashing completely.