zig zag lines on surface

Hi all, I need to create straight zig zag lines across a surface as shown. I need to be able to adjust the spacing and rotate the angle of the lines relative to the surface in the xy plane. I've tried extracting the iso curves and "offset on surface" with no success. Also, how to joint the ends? Any thoughts?

Attachments:

1.jpg, 333 KB

Replies to This Discussion

Permalink Reply by Chris Tietjen on April 15, 2011 at 9:20am

Are you trying to generate a CNC toolpath?

Chris

Permalink Reply by WoodDuck on April 15, 2011 at 9:24am

yes

Permalink Reply by Chris Tietjen on April 15, 2011 at 9:37am

Just to check but I assume that you know you can do this with flow along surface in Rhino and that it's the GH solution that's important.

Chris

Permalink Reply by WoodDuck on April 15, 2011 at 9:45am

yes, I know you can use flow along surface or project but I would like to use Gh so I can modify the spacing "live". Also I'd like to find a way to rotate the toolpaths.

After posting, I re - found this article on Design Reform: http://designreform.net/2010/01/rhino-grasshopper-create-tool-paths...

It shows the generation of toolpaths on a surface which is great, but I still need to alternately connect the lines to form one continuous toolpath.

thanks

Permalink Reply by Chris Tietjen on April 15, 2011 at 9:52am

I haven't looked at your link yet but you can use the 'Morph>MapToSurface' component which works just like 'Flow Along Surface' in Rhino (at least that's my quick take on it). The spacing and rotation of the path could be done on the source surface before the mapping takes place. I'll give it a try but may run out of time and will have to come back to it later.

Chris

Permalink Reply by Chris Tietjen on April 15, 2011 at 6:26pm

I'm not sure how you envisioned the rotation but here it's based on an area centroid.

Chris

Attachments:

CNCPathGenerator.ghx, 186 KB

Permalink Reply by WoodDuck on April 15, 2011 at 7:42pm

Thanks - this is very helpful. I like the way you flipped the curves and weaved them to create the single toolpath. Part one accomplished. The mapped toolpath is not quite behaving though in that it doesn't follow the target surface and curves up at the boundary of the surface..

thanks for your help with this.

Attachments:

1.jpg, 288 KB

Permalink Reply by WoodDuck on April 15, 2011 at 9:36pm

I have most of it now, using elements of your definition Chris and the one from design reform. I have a single path that follows the surface with a variable stepover.

I'm still having trouble with the rotation though. I think I need to rotate the actual isocurve points around the perimeter of the surface so the isocurves will always be generated only within the bounds of the surface. No idea how to do that..

Getting close though!

Attachments:

New CNCPathGenerator.ghx, 156 KB

Permalink Reply by Chris Tietjen on April 16, 2011 at 10:28am

I guess I haven't got the MapToSurface component figured out yet. Here's another try using the ProjectToSurface component with skewing instead of rotation. Still looking into how this might work with your def.

Chris

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