CONSTRAIN VOLUME

hi all - i am preeetty new to grasshopper, and am looking for a way to constrain volume of a lofted + capped surface.

basic principle: i want to have a set volume lofted between two curves from rhino so that i can edit them individually, the problem is i want to be able to change the curves and have the volume of the lofted and capped "box" stay the same. i know this is going to be alot harder than it seems haha

thanks

Replies to This Discussion

Permalink Reply by Mårten Nettelbladt on June 19, 2010 at 6:39am

You'll need to decide a property that Grasshopper can change to make sure the volume stays the same. Perhaps the loft distance (distance between the two curves)?
In this case the Galapagos solver is useful.

Try the attached example.
First load the rhino file, then the grasshopper file.
Edit the curves as you like (In the Rhino window) just make sure they stay planar or else the "Cap holes" won't work.
Enter the desired volume in the yellow text component.
Then start Galapagos by double clicking that component / choose "Solver" / press "Start Solver"
Galapagos will change the loft distance and try to find a setting where the volume of the loft matches the desired value.

Good luck!

Attachments:

Permalink Reply by KRANIERI on June 19, 2010 at 4:02pm

thanks for the fast response and yea tweaking that length seems like a good place to start but for some reason the galapagos solver isnt coming up on my grasshopper doc, i tried to find it, is it a download? (im sorry, im very new to grasshopper)

Permalink Reply by Mårten Nettelbladt on June 19, 2010 at 4:15pm

Have you got the latest version?

Permalink Reply by KRANIERI on June 20, 2010 at 4:17pm

i figured out a different way actually, seems a little more direct, let me know what you think.

Attachments:

Permalink Reply by Mårten Nettelbladt on June 21, 2010 at 5:31am

That seems a lot more straight-forward. I get different volume results though when I change the curves. It may need some fine-tuning.

Permalink Reply by KRANIERI on June 21, 2010 at 1:46pm

yes i think it has to do with the equation for volume. it may be a bit restricted to an extruded rectangle - let me know if you have any other thoughts, im very interested in grasshopper as an initial design/sketch phase tool in addition to its other applications

RSS