how to model a nylon webbing sling?

[JohnFox]

Hi guys,
one of my assemblies contains a nylon web sling. I can model this in a simple fashion by sweeping a section profile along my guide. How would I tackle this if I wanted to model the actual structure of the nylon weave? Is this practical? Has anyone accomplished this before or should I be looking to add a 'weave texture' at the render stage...

many thanks,
John Fox

 

[cowski]

If you are using 'off the shelf' material, I would suggest modeling a sheet body the size you need and adding a texture or cross hatch pattern later. If you are the manufacturer of the weave, you will probably need something more detailed to define the weave.

 

[JohnFox]

Hi Cowski,
ok, thanks. I am not the manufacturer so that would work ok. How do you add a texture to a sheet body and where would I get the texture from? (Can I take a photograph of an existing object with the correct texture and use this?)

many thanks,
John

 

[JohnRBaker]

You'll need a Studio License and as long as your image is in either .tif, .jpg or .png format you should be good to go.

As to how you assign a texture, model your 'sling' as a simple surface and then go to the 'System Materials' tab on the Resource Bar and generally for something like this I start with White Plastic, so drag the Colors Plastic White 'icon' on to the screen and drop it on your surface. Now go down to the new tab which was just added to your Resource Bar, 'Materials in Part' and select the object labeled 'White', press MB3 and select 'Edit'. When the dialog comes up, select the tab labeled 'Pattern' and under 'Type' select 'Wrapped Image'. Now select the 'Image' button and browse to where your image is stored and select it (now be careful here, once you make this selection, you can't move you file since this is a link to your image file so if you move it and then go back and try to render your model it will not be able find your image, so if you're going to do this a lot, I would establish a sort of library where you know where these images can always be found). Now you may wish to change the size and orientation of the 'image' relative to the surface that you select and to do so you use the options under tab labeled 'Texture Space'. You'll want to play with this a bit to get the hang of it and even if you're eventually going to use the High Quality Software Rendering to produce your final image, you can work in the Studio Display mode which makes it very easy when manipulating the textures since this will allow you to preview your results.

Anyway, give it shot and is you get some results you like, if you're allowed to, share the pictures with the rest of us, OK?

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

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

 

[JohnFox]

Hi John,
many thanks for the advice. I took my 'texture' photo and assigned it as you described. It actually worked pretty well. I played with the options and am starting to get the idea. I will share the pictures as soon as I can and hopefully when they are not to embarassingly bad!

I have to say based on my small amount of experience this is the area in which I find NX the weakest. It is very easy to apply textures and renders but really, really difficult to make them look 'real'. Mostly the textures and materials look entirely different as to which their names would suggest.

Is this an area that has not been developed or simply my lack of skill? What are others thoughts on this? Can anyone share some parts with assigned materials and textures that they are really happy with?

many thanks,
John Fox

 

[JohnRBaker]

It's an area where we have not put a lot of effort recently. However, that being said, that does not mean that people have not been able to use it successfully. After all, have you ever seen one of our calendars where we publish images submitted by our customers from around the world? All the images are created from models created and rendered with software from Siemens PLM.

Here are a few examples of images submitted for publication in recent Siemens PLM calendars:

For a more complete look at some of the image, visit our image gallery at:

http://siemens.pmhclients.com/index.php/globalimage

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

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

 

[JohnFox]

Hi John,
that is very impressive! Do you have one example of a worked part and rendered image so I can see how it is done?

many thanks,
John Fox

 

[JohnRBaker]

I'll have to look at my personal collection, since with the items shown in our calendars (and on that website I posted the link to) we only have rights to the final images, not the models which they were created from (we only ever ask for the images, not the part files themselves). Although some others here on Eng-Tips may have done some stuff like this and may wish to offer their own efforts as an example...

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

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

 

[BOPdesigner]

"All the images are created from models created and rendered with software from Siemens PLM."

How do you know this if you are only receiving the final images?

 

[JohnRBaker]

We know that they're customers and that they're using our software so at that point you've just got to trust them. Besides, the organizations submitting the images must sign the equivalent of a 'photographer's release' allowing Siemens PLM to use the images in both the Siemens calendar and any other marketing or promotional activity where they may be deemed appropriate and useful. This release spells out the 'rules' under which the images were solicited, delivered and will eventually be utilized.

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

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

 

[JohnFox]

Hi John,
if you could have a look in your personal collection and if anybody else felt like doing the same and putting up the parts and rendered images that would be cool. I am sure quite a few people would like to learn how it is done properly...

many thanks,
John Fox

 

[JohnFox]

Hi JohnR,
how would you create the effect as in the first image above where the parts are sitting on top of the drawings? One of the drawings has a curve in the sheet of paper to make it look more realistic I would imagine, any ideas how to achieve this effect?

many thanks,
JohnFox

 

[JohnRBaker]

First get an image file of a drawing, be it of a CAD generated drawing or a scanned in paper drawing. The create a Sheet Body of the desired size and shape, and then apply a 'texture' to the face of the Sheet Body using the image file of the drawing using one of the texture options that says place a single image fitted to the face.

For some other, although older, images created using NX (Unigraphics back then), go to...

http://plmworld.org/museum/gallery/Unigraphics_as_art.htm

...and scroll to near the bottom of the page, although some of the earlier images does show how things have evolved over the years (that first image the Starship Enterprise was done in 1977).

Of special interest is that image of the cutaway of the butterfly valve with the magnifying glass...

...as the 'magnified' part of the image was NOT faked. I actually created a 'magnifying glass', positioned as you would expect it to be, with an accurately modeled 'lens' assigned the material Glass which included not only the color (clear) but also an index of refraction. In fact, if I were to have moved the magnifying glass back further away from the butterfly valve, the image would have eventually reversed itself as would happen in the real world. The rendering engine we use with NX was developed by a group of optical physicists originally intended for designing optics, but they discovered that they could sell many more licenses if they added materials and rendering capabilities, however they left in all of the code which simulated the way light passed through materials, such as glass, which has an index of refraction. In fact, I once messed around with trying to position a series of lens to simulate a telescope but never really finished it, however it was showing promise ;-)

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

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

 

[JohnFox]

Hi JohnR,
that is awesome, thanks for sharing. The history of the engine development is really interesting to hear. Someone should write a book about that sort of thing. Good literature in this area is really lacking. Thanks for the insight as to how to create the paper effect. I will give that a go...

best regards,
JohnFox

 

[hudson888]

There are also plenty on my website that I've created with NX including links to some videos.

Best Regards

Hudson

www.jamb.com.au

Nil Desperandum illegitimi non carborundum