TCL TO GET MIDLINE

'Midline' or 'midsurface'?

A sample of HM model?

hi nyuyen , i mean midline of a solid cylinder with some diameter (lets say 100mm). Pls Imagine there are some, 50 cylinders of such kind or say wires ( unattached to each other) and i want to extract midline for all of them at once using a tcl..... unfortunately i dont have the model so couldnt attach.. i am however attaching an image for ur understanding

thanks in advance 

<?xml version="1.0" encoding="UTF-8"?>

Hello everyone, I'm retriving this topic again in order to see if someone could help me.

I have a 3D model (tubular structure) I want to mesh with 1D CBAR elements.

Anyone please know a quick way to get the midline of the 3D model tubes?

Thanks in advance.

Panel geom>lines>mid lines

Does it help?

Hi tinh,

Thank you for your attention to this matter.

I'm not really seeing your point.

I have a strucutre like this and i need to extract all midlines (in blue) in between.

Could you please be more clear?

Thanks

• Node => Arc center
• Build curves from above nodes

Got 'midline' of tubes /emoticons/default_tongue.png' srcset='/emoticons/tongue@2x.png 2x' title=':P' width='20' />

Ok I got it, thank you so much Q.Nguyen-Dai and tinh.

But know I have another question, because I have a big structure I do not want to do all the process by hand ( that would be very time consuming)

Is there a TCL scripting code to that automatically? I mean just selection all teh tubular structure at once and give me all the midlines?

Thank you for your kind support.

A such script is not yet found.

If you find it or write it, pls share us.

I think it is rarely used so nobody write.

Yes, if it takes 4h to write this script and you use only one time, it's NOT worth writing.

I still dont get how you create midlines from a curved solid tube. 

Attached the sample picture of geometry.  I want to write a code to extract the midline of the tube and calculate thickness. greatly appreciate of anyone can help me

<?xml version="1.0" encoding="UTF-8"?>

Maybe you can do it (midline) with some CAD softwares.

Ya. I know CAD software can do it on fly. but I need to extract in Hypermesh.  Its the first step in my analysis and I always gets CAD without midlines. 

I tried writing TCL code for this by sequentially selecting outer parallel lines and finding midlines and joining all of them. But I need more robust code

I tried writing TCL code for this by sequentially selecting outer parallel lines and finding midlines and joining all of them. But I need more robust code

That's problem if the 2 lines are not slice the sequence in 2 equal parts.

To specify mid line, i suggest you to extract parametric uv lines of each outer surface. In simple case you will get u or v as arcs, find arc centers and connect them you will get mid lines