Bending wood

Hi Guys!

I'm trying to simulate bending of wood on grasshopper. I came across the geometry of bending blogspot recently. This person( Maarten Nedelbaldt) has formulated geometric relations in bending and developed a vb script for the same. Since I don't understand I tried to develop this grasshopper using the same logic. The problem is that the length of the strip changes as it bends. So I tried using Kangaroo2.0 ( and right now I don't understand Kangaroo2.0 at all) the previous version was much simpler to understand. So I couldn't get this approach to work aswell. I'am attaching all the relevent information for all to probe into. Any help is much appreciated.

Cheers!

Attachments:

To simulate.png, 46 KB
Bending simulation.gh, 28 KB

Replies to This Discussion

Permalink Reply by Aditya Tognatta on November 20, 2015 at 5:27am

Kindly help guys!!

Permalink Reply by Aditya Tognatta on November 20, 2015 at 5:30am

All I want to do is generate Elastica curves or maybe conru spiral curves, maintaining the overall length, but manipulating the start and end points of the bending curve.

Permalink Reply by David heaton on November 23, 2015 at 8:34am

I am in a similar place to you as well. I was previously working in the first kangaroo, but not totally understanding Kangaroo 2

Permalink Reply by David heaton on November 24, 2015 at 9:37am

Hey, I found a script written by David Lister that simulated a piece of bending plywood and included rotation and twisting along with torsion resistance. Attached you will find his script as well as the re-write that I did to bring it into Kangaroo 2 underneath it (his is currently disabled). It is so much better with the new solver. The only issue I had was keeping the original mesh. I was only able to retrieve the points that made it from before and then with those points I reconstructed them into a surface. If you have any suggestions on how to keep it a mesh, I am all ears.

Cheers,

David

Attachments:

NEW REBUILD (AIR_GH09.61_TwistingStrips_DWL).gh, 42 KB

Permalink Reply by Aditya Tognatta on November 25, 2015 at 9:05am

Hi David!

I appreciate the input. Its great work! Especially with only .1% error on length. I wouldn't care to much about the mesh output. Although I shall do an iteration on the same with surface input and output both.

Thanks David

Cheers,

Aditya

Permalink Reply by Aditya Tognatta on November 26, 2015 at 5:01am

Hi David I wanted ask a few question regarding your Kangaroo script. I don't quite understand the gaps in the Lines you created for the Angles in kangaroo. Kindly Explain! Check out the files I attached for a better understanding of the problem.

Thanks in advance!

Attachments:

Untitled-1.jpg, 514 KB
Untitled-2.jpg, 515 KB

Permalink Reply by David heaton on November 30, 2015 at 3:18am

Hey Aditya,

So I could have set it up wrong, but from what I understand, there is a big difference in the original "Bend" component and its K2 version, "Angle". To be honest I used it because it had the same icon. The difference is that the original bend component made use of points to calculate the lines and the new "angle" component uses lines. Knowing this I created two lines from David Lister's original 3 points. Line A is point 1 to 2, and Line B is point 2 to 3, which I thought would produce the same angles to work from as the original 3 point bend component. Hope this explains it a bit. I look forward to seeing what you do with it :D Cheers!

Permalink Reply by Nick Bruscia on February 2, 2016 at 4:52pm

Dave and Aditya,

A slightly cleaned up version with a higher res mesh, attached. You could obviously replace the Grab with a different way to bend the mesh edges. Add some strength to keep it from slightly stretching as well.

Attachments: