Learning Forum

[Zizi96]

Hello 

I'm modelling up a composite monocoque. To do so I need to place a composite strip that extends 75mm from each edge of my model shown in the attached picture. The green lines highlight the edges.

Can anyone tell me the best way to off set a line 75mm from the green lines in design modeler? 

I'm also open to alternative suggestions.

 

[peteroznewman]

I have used Surface Extension with some success. If you want to archive your project, you can attach the .wbpz file to your post above and I can try it.

[Zizi96]

Thank you for your time Peter.

 

Just to confirm I only need to add a line not a surface. Also the offset line needs to be 75mm back from the shown edges not extended.

 

Edit: My file .wbpz is 13mb so its far too large to attach, is there alternative way I could get it to you?

 

[peteroznewman]

Okay, you want a line on the existing surface, 75 mm inside of the existing edge.  I misunderstood and thought you wanted the line on the opposite side of the existing edge. 

The monocoque was created from solid bodies and you used a shell to create a thin solid then you created the surface using a midsurface feature. If you hide the midsurface, you can create a 75 mm offset surface on the edges of the thin solid by using the Solid Extension (Beta) feature with a negative distance of 75 mm. Slice the midsurface using the offset surface. Create lines from edges, then unite the slices midsurface. Those operations are in the attached 18.2 archive.

The post attach file size limit is 120 MB so you should be okay if you want to attach your archive.
If you first Clear Generated Data on the Mesh/Model item, then save, that can significantly reduce the archive file size.

[Zizi96]

Okay, you want a line on the existing surface, 75 mm inside of the existing edge.  

Correct 

 

The monocoque a imported surface body so I'm not sure if the mid-surface feature you mentioned will work. I've attached the archive if you wanted to take a crack at it yourself.

 

Thanks

 

[peteroznewman]

I use NX11 for CAD and it has an Offset Curve in Face feature. 75 mm goes outside the dimensions of the monocoque. What do you want to do in that case?

The back opening could not generate an offset due to a self intersecting curve.

The method I outlined in the first post requires the solid body before the midsurface operation if you want to create the lines in DesignModeler. Do you have the solid model available before the midsurface?

[Zizi96]

I need to add the lines in order to define an area which requires an extra layer of composite material, therefore the extended line only needs to reach the boundary of the monocoque model. Where 2 areas come to overlap can they be merged into 1 area?(As shown in the attached image).

The crude drawing attached should give you a better idea of what I was trying to achieve, the highlighted orange area is where the extra layer of material is required.

Ok, I think this answers my core question. My take learnings from this are that;

• If I want to define a region on a surface model I would need to do so before importing the surface model into design modeler.


• Alternatively I could import the solid body model and use the mid-surface feature you previously outlined

 

[peteroznewman]

The more geometry prep you can complete in the CAD system, the better off you are.  What is your CAD system?

[Zizi96]

I've been learning Solid-works for the past year and CATIA for the past 2 years. I'll try to do this in solid-works later today.

 

Again thanks for you time and help Peter

[Zizi96]

Hi Peter. Quick question.

What file type did you use export the NX model with the offsets you made (as shown below) to ANSYS?

I've offset my lines in solidworks, however when I import the model into ANSYS as a step file I lose all the offset curves I made. Only the surface model is imported. I've also tried keeping the model as a SLDASM in Spaceclaim, also to no avail.

 

[peteroznewman]

When I have to import curves, which is rare, I have to remember to check the Line Bodies
and at the bottom, Mixed Import Resolution to Surface and Line. Does that help?

It that doesn't work, zip up your SW assembly to attache and I will see if I can get it to work.

[Zizi96]

I presume you're referring the the properties menu on the right. When I click Geometry I don't get the same options as shown in your picture. By the looks of it that would resolve my issue.

I've also attached the solidworks  file

[peteroznewman]

You have to pick the properties on the leftmost Geometry cell, not the shared cell.

You attached the STEP file which does not have the curves in it. Do you have a zip file of the solidworks files that include the curves?

[Zizi96]

Clicking the leftmost geometry cell with the tick, then right clicking and selecting properties, I get the same options as shown above

 

I've attached the solid Solidsworks file of the file I'm attempting to import. You should be able to see the 3D sketch I'm trying to import, it's a 3D sketch on the rear surface of the model.

 edit: For some reason the forum won't allow me to upload SLDPRT files so I've uploaded the STEP file, let my know if you can think of a workaround. Thanks

 

 

[peteroznewman]

The forum allows zip file archives.  Take your SLDPRT file and zip it.  Then attach the zip file to the next post.

There are no curves in your STEP file.

[Zizi96]

Ok, here is the zipped version of the file. That should contain the sketch information.

 

[peteroznewman]

I used my SolidWorks Plug-in and checked the items I showed above, but no curves came into Mechanical.

In SolidWorks when you were exporting STEP files, did you check the 3D Curves option?

It is possible to import a mess of curves into DesignModeler using STEP.

[vganore]

Thanks, Peter for helping here. Awesome. Some additional comments related to ACP:

"You do not need to subdivide your geometry for every composite patch. You should attempt making the patches with the help of Tube Selection Rules in ACP."