Creating a System with one of the axis normal to surface.

Altair Forum User

Hi all, my name is Lucas.

I have met a problem with creating the system with one of the axis normal to particular surface. Basicaly imagine that you have a 'lips' and on the edge of it you want to creat a System with one axis normal to the curved surface? I vas trying several option but I have failed. Maybe someone over here have similar task, and was able to do it?

Regards,

Altair Forum User

Hi Lucas,

i don't understand what you mean.

A curved (Nurbs) surface has a different normal axis at each point.

For a flat surface it is very simple...

Regards,

Mario

Altair Forum User

You can get a normal vector by:

Create nodes along a curve.

Offset the curve.

Create the same number of nodes along the new curve.

Create a normal vector from two nodes

But, not sure how to get the tangent node you need to create a system.

Altair Forum User

Create nodes along a curve.

tinh

Hi Lucas

so the problem is you could not find out the normal of that surface?

1) if the system origin is not in that surface, you can project a copy of origin normally to surface, you will get the normal of surface by 2 nodes

(origin, copied_origin), then you can specify axis for system

2) if the system origin laying on that surface, you can associate it to surface, using tcl command hm_getsurfacenormal to get normal vector of surface at system origin node

then using *createvector, *translatemark to create 2nd node on normal vector direction

or another way, you can also use Surface Edit/Offset to offset a copy of that surface then respectively project normally to 2 surfaces to get normal vector

rgds,