CAD (.STEP) to Maya IMPORT - Tutorial and Questions

[Joghurt]

Hi, folks!

 

First of all: I'm very sorry that my english isn't the best. But I hope you all understand my problem.

I'm also relatively new in the CGI-business (I just started with Maya sine a few month), and it could be that some step of my worflow sounds a little bit crazy.

 

In my first project i wanna do a product-visualization of an industrial robot which I designed with the CAD tool CATIA.

Now i wanna do some small visualization clip of this robot with animations and HiRes-renderings with Vray for Maya2011.

 

I feel save with the basic modelling and animations tools of Maya. I also acquired advanced knowledge in rendering techniques with Vray.

My problem for now is "just" the import of the CAD file. I didn't find any good tutorial/infos for importing 3D CAD files in Maya so I started a mass of importing-test.

But with no realy satisfactory result

 

I will now explain my importing workflow, in hope that someone of you spot some errors in reasoning or some cardinal faults.

 

My Workflow:

(comment: the file format is .STEP exported from CATIA)

 

 

• 1. load DirectConnect Plug-In in Maya
  

 

• 2. click on import options and choose as file type (STEP_DC)
  

 

• 3. all other import options stay unchanged
  

 

• 4. click IMPORT and wait 2h (it is a very detailed robot model)
  

 

Ok, so far I have a model in NURBS but for UV-mapping and redering I don't wanna use NURBS (I also modeled the environment in Polys)

I thought it's a good idea to do a Polytrans so I do the following steps:

 

 

• 5. Modify > Convert > NURBS to Poly (this is the most confusing step for me. I don't know which type and which tessellation method is the best. I also don't understand the settings of each tessellation method)
  

 

• 6. In most cases i choose "Quads" as type and "general" als tessellation method but that doesn't work well with all kinds of geometry. So I do the different parts with different tessellation methods. But this method is very time-consuming and very inconvenient.
  

 

 

• 7. When all parts of the robot are converted in Polys I combine the components with "Mesh > Comine" function.
  

 

• 8. After that i deleted the histoy of the parts.
  

 

For edged parts these steps are acceptable but in my robot model there are also some soft surfaces. In these cases i do an curve improvement bevor I start the Polytrans. In the curve shape go to tab "NURBS Surface Display" and increase the "curve precision" and the "Crv Precision Shaded" values.

 

This workflow creates some good geometry results but with an tremendous amount of Polys (90 million faces. My system is dramatically slowing down at circa 100 million faces). It is also very time-consuming.

 

I will be so thankfull if someone of you have some tips or improvement suggestions for me. Every opinion will help me.

 

Many thanks for all your posts!!!!

 

Best regards

Niki

 

P.S.: i don't have any chance to use nPower-Software or Onkino