How can I 'wrap' a solid body around a spline curve?

[JohnFox]

Hi Guys,
I have a solid body part which has a variable edge profile. I drew this as a sketch and extruded it to the required thickness in the model. This works great for engineering production drawings but now I need to make assembly drawings that show the part form which is curved not straight (the part is made of rubber).

When all the assembly parts are put together the rubber strap now has a curved shape. Can anyone tell me the best way to think about this and take my straight rubber part and map it to my spline curve.

The long way would be to create multiple sections along the length of my spline curve and use 'through curves'. This is tricky because of the changing edge profile so all the sections would be different and getting the sections into the correct location would also be difficult.

It also seems a little silly as I already have my part.

What is the NX way to do this?

many thanks for any help!
JohnFox

 

[hudson888]

Giving us an image or even a file would really help to understand your requirement. You're most probably looking at creating some kind of sweep and while I have several in mind that may work it is hard to select the appropriate one based upon your statements alone.

Best Regards

Hudson

www.jamb.com.au

Nil Desperandum illegitimi non carborundum

 

[JohnFox]

Hi Hudson,
I have attached an image. I want to wrap the red 'strap' around the extruded spline. I hope that gives you a better idea.

many thanks,
JohnFox

 

[jerry1423]

It is possible to show us a picture of what you are working with?

 

[JohnFox]

Hi Jerry,
the image is attached in the above post. Click the link to download...

thanks,
JohnFox

 

[hudson888]

Lucky that I asked for the picture I had three possibilities in mind none of which were anything like what you would have needed. The answer I suspect is that it can be done somehow with great difficulty. Either by calculating or iterating towards a close approximation rather than a definitive answer.

The tools that do exist are better for unwrapping than wrapping. For non uniform shapes there is a specific tool in the Sheet Metal>Forming/Flattening module. Fewer users have the license for it and it will only unwrap to the best of my knowledge. The technique relies on a finite element method so that if you interpolate a result it may simply be able to un-interpolate it for you to achieve the original.

On the other had if you're willing and able to approximate your splines to arcs then the attached example may prove instructive. There is way more in the file than you probably need, but I was interested to see if what I could achieve and included extra steps used to prove out my method. Even if you don't follow my lead on this I think it may offer means to approximate your geometry that are better than nothing.

Best Regards

Hudson

www.jamb.com.au

Nil Desperandum illegitimi non carborundum

 

[JohnFox]

Hi Hudson,
many thanks for the answer. I will have a look at your attached file and let you know how I get on. I can approximate my spline to arcs.

I have to admit this little problem had me stumped. For once I am happy it is difficult! I have used NX quite a bit now and have seen nothing that would allow me to achieve what I needed to do accurately and easily as the section is rather variable. I was hoping there would be a less clunky way to achieve the desired result rather than have multiple sections follow the guide which would be a pain to set up (if at all).

best regards,
JohnFox