Stitch a hollow volume

[digiformer]

Is it possible to get a completely closed but still hollow geometry stitched? Like a ball with material thickness but no hole in it.

So far i miserably fail on that challenge 🙂

Tobias


Reply From: Tekbot
Date: Aug/29/08 - 04:41 (GMT)

Reply
Re: Stitch an hollow volume
i think stitching is a edge based thing. no edges on a ball with part thickness.

try Inventor.

[digiformer]

As an edge is the border of a surface i could divide a sphere into a geometry with edges. Or try a cube. It is not working. So it is not possible in Alias? Limitation?

Sure, i know other software packages do this...i just was trying not to switch tools...

Greetings
Tobias

[hansgeerdink]

Hi Tobias,
I dare to question the use of your proposal. Think about it:
We are creating surfaces; a sphere is a special thing with no edges at all....
So, for AliasStudio it is not possible to calculate intersecting surfaces, simply because the surfaces do not intersect.
So far I can think of only 1 option:
1. Create Spheres, change surface normals of the inner sphere to point inward, group them and there is your object.
However, I am still curious to why you would create a suface that is never seen? (the inner sphere...)
Beware, because once you do want to intersect your "easter-egg", things will get more complicated with my solution. In that case you should always keep in mind Alias creates sufaces period.
Hope this helps!
Cheers,
Hans

[tekbot]

yeah im really curious where and why you would need this?
im baffled why this is necessary.

[digiformer]

You are quiet right, i cant think of a product or production process which would realy depend on having totally closed hollow bodies.

Ball or cube - its irrelevant, it could be any appearance.

Beside balls, think of chocolate Santas or maybe toys for babies. Snowdomes without the necessity to assemble parts. 3D engraved crystal products. The problem would occur when i construct foam-structured "things", maybe transparent bike frames or whatever. Then i might want to design the "bubbles" or maybe pipes inside the material. As soon as i have to hand out a stitched model for those things, i have to think about my issue.
Nobody knows what hits us in the next years.

I just stumbled over this problem during work. I made a few attempts and then i thought i just ask you guys. Its sure nothing like "ah see! studio cant do this! hehe!" Its more about understanding Studio and having answers when questions like this come up.

As i understand it, Studio is absolutely not working with volumes. In closed shells the actual inner material is not recognized by studio. So we never will be able to substract something from this body. Boolean actions in studio are just something like a more complex intersect+trim automatic. We need an calculatable intersection to the inner "room".

Right?
So its just a simple limitation. Workarounds are known.

I will test your suggestion with the grouping and importing this into ProE. Lets see.

Greetings to all...
Tobias

[hansgeerdink]

Hi Tobias,

Yes, it sounds like you get the picture! 🙂
As a matter of fact, as I had written my previous reply I thought of a transparent object having thickness, when rendering, light will break more then once (refraction)...
Good luck!
Cheers!
Hans

[digiformer]

To close this case,

ProE does not put the two shells together to one body. There seem to be two options to import geometry: "single part" and "assemblies".
Single part doesnt work this way and importing an assembly results in two parts.

Greetings
Tobias