Sketched Splines

[pedja14]

Let us consider the following scenario:
You get complex styled lines from industrial design department which you have to reproduce and build the surface and solid geometry after. You are going to use these lines only as visual references.
In my experience with this kind of highly styled product design the best way to reproduce and closely follow these lines in sketch are the splines.
However I find very difficult to manipulate these splines in CATIA 5 and almost impossible to get close to desired line.
Is there any other way to do it or I am missing something.
The ones here who are familiar with surface modeling in ProE
are more likely to understand exactly what I want.
ProE can manipulate splines in a very precise manner by dragging and that is what I am looking for in CATIA

 

[Configurator]

You're saying you want to pull on the control points?

Use the Freestyler workbench (FSS) if you have it.

 

[pedja14]

I have the FSS but it cannot use it because I need parametric geometry.
If I adjust curve in FSS the changes will not propagate in the rest of the geometry. If a surface has been extruded from that curve in WSD it will not be updated
So basically I need exactly the FSS capabilities but in a parametric environment.
Is there such a thing in CATAIA 5 ?

 

[Configurator]

No, for whatever reason, it's all datum.

Tweaking your spline with FSS and then using the replace function (replace your old, associated spline with the new one) might work. It's annoying since you won't see the changes propagate as you pull on the points, but give it a shot (unless anyone else knows something).

 

[jackk]

If you Ind Design dept uses a different CAD system (Alias, Rhino, etc), try converting their surfaces into CATIA.

 

[pedja14]

ID surfaces rarely can be used in mechanical design regardless of the software simply because they are created with no prior knowledge of the detailed mechanical constraints and limitations. In almost every case these surfaces has be adjusted after.
Anyway thank you all that answered my question

 

[dbeat]

In Sketcher you can constrain the control points to your reference lines and then drag those control points around until you get your desired spline.

For further control you can double click on any control point and select the 'tangent' box. This creates a tangent arrow head that you can further constrain to the reference lines in any way you please.

I hope this helps and that I'm not misunderstanding you problem.

D.

 

[Azrael]

Have you considered not to sketch and insteas use "work on support" with ordinary splines in GSD which are easier to control?

 

[jcmbl]

dbeat: u r probably talking about the passing points and not the control points. They are different.

One way to create parametric NUPBS: construct through constraints the control points in a sketch. This is easy for a simple model. The manipulation is up to you: design table, or by simply doing some scripting. You didn't mention if you work all the time with GUI or batch.
Another way, suitable for batch and for simple and roughly a priori known model, you can use an output file (e.g., stp) by laoding it up back to catia. In the stp file you get the coordinates of the control points. Then it's easy to manipulate the model by parameterizing it. As a starting point, you can save a spline (that's a NUPBS definition) into an output file with its corresponding control points.

Hope this helps