How to reproduce the same CATIA surf in NX8.5 ?

[PSI-CAD]

Hi,

I would like to reproduce the same CATIA surface in NX8.5

I have succeed with bridge surface but the Tangent Magnitude is 1.45 instead of 1 in CATIA (part NXBlend)

But with another example (part NXBlend_2) the Tangent Magnitude is always setted to 1 in CATIA but 1.25 in NX !!!

TIA


Regards
Didier Psaltopoulos

http://www.psi-cad.com

 

[KhimaniMohiki]

I would assume its down to the differences in the mathematical code between V5 and NX, doesnt CATIA use NURPS instead or NURBS? Could that be why you are seeing a difference?

Does this even make any difference as your end result is the same?

Khimani Mohiki
Design Engineer - Aston Martin
NX8.5

 

[PSI-CAD]

Hi,

Thanks for your answer. I am not a CATIA Expert and I don't have CATIA on my laptop

What's the difference between NURPS and NURBS ?

It's a little bit difficult to explain. My Customer try to adapt in NX a code developped in CATIA. And the Tangent Magnitude (Tensions in CATIA) must remain to 1 ?

Regards
Didier Psaltopoulos

http://www.psi-cad.com

 

[JohnRBaker]

You say NX 'always starts' with something different than was CATIA's default, but if you adjust the NX parameter to be the same as it was in CATIA, are you getting the same results? If so, what's the problem?

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[PSI-CAD]

Hi John

We don't have the same results with the same default parameter in NX and CATIA (Tangent Magnitude = Tensions = 1)

The body()"Surface CATIA" is obtained with tension=1 within both parts in CATIA

My problem is that in NX8.5 "Tangent Magnitude" must be set to 1.45 in NXBlend.prt and to 1.25 in NXBlend_2.prt

Maybe should it be equal to another value than CATIA but the same in both case !!

Do you agree with that ?

Regards
Didier Psaltopoulos

http://www.psi-cad.com

 

[JohnRBaker]

Apparently the meaning of the two 'settings' are different. If they are using a different scheme to control some aspect of the shape of a surface then it's not surprising that one would need to enter different values in one than the other to get the same results. As to why in one case NX use one value to replicate what CATIA entered as 1.000 and a different value in another case to get a similar match, in no way means that something is wrong with NX. All it means is that something in the math was different.

Now IF we could find someone who was fully-versed in the mathematical underpinnings of BOTH CATIA and NX, at least with respect to surface creation, than perhaps we might learn why what you're seeing is what it is. But barring finding such a person, this may have to remain a mystry, as it were.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.