Fixing loft

Can someone direct me as to the best way to fix this loft. My intent was to have three spherical bulges in the middle of a pipe. I did this by lofting various cross sections of curves. However, it comes together very sharply when it should be more rounded and spherical. Any advice.

Attachments:

ar8.gh, 16 KB

Replies to This Discussion

Permalink Reply by Hyungsoo Kim on October 19, 2017 at 1:43am

I'm not sure about the resulting shape is what you'd like to achieve, anyway, this could be a way of how loft should look alike.

Attachments:

ar8_re.gh, 23 KB

Permalink Reply by M Sal on October 23, 2017 at 7:51am

Thank you! That certainly looks better. I did want the bulges to be a bit more spherical, like in the attached image. Any advice to get there?

Attachments:

Capture.PNG, 35 KB

Permalink Reply by Michael Pryor on October 23, 2017 at 8:00am

Less density of curves = less sharp bulges. Look at your attached image and the answer is there. There is only 3 curves and far spaced out.

Permalink Reply by M Sal on October 23, 2017 at 8:08am

thank you for your reply! I'm sorry, I am very new to grasshopper. Are you saying to increase the degree input to the Rebuild Curve block? That doesn't seem to change the roundness much.

Permalink Reply by Michael Pryor on October 23, 2017 at 8:24am

No, I'm saying to have less curves, and space them further apart... The issue has nothing to do with grasshopper, this is just a basic understanding of modelling in general. See image below. So just define your geometry with less curves and space them out further to get nice rounder curvature.

Permalink Reply by M Sal on October 23, 2017 at 8:38am

Sorry, I should have said new to modelling. That makes sense. I started to add more curves initially because the loft attached in a sort of concave fashion (see attached file with fewer curves). Is there an alternative way to get it to pop out at the attachment point between the small radius circle and the larger radius tri-circle union, instead of caving in?

Attachments:

ar9.gh, 25 KB

Permalink Reply by Michael Pryor on October 23, 2017 at 10:16am

The issue is your curves are a bit harsh from one to the other in terms of knots/kinks. So the loft interpolation kind of loops over itself like the following image shows.

So I added some blended curves between using my plugins (Pufferfish) tween curves component which is an improved version of GH's native tween curve. Then I added a factor to move the blends closer or further away from the center curve in the z direction which lets you control the bulged. You can get the plugin here: http://www.food4rhino.com/app/pufferfish
Attached is the fixed definition.

IF you want to change where that crease in the loft is then you can adjust each curves seam independently until they align how you like. I see you are using a kind of automatic seam adjustment with closest point however to get what you want it's sometime easier to just adjust them each till you get the desired results.

Attachments:

ar9-mp.gh, 28 KB

Permalink Reply by Michael Pryor on October 23, 2017 at 10:27am

and by adding a few more tweens.

Attachments:

ar9-mp2.gh, 35 KB

Permalink Reply by M Sal on October 27, 2017 at 9:13am

Thank you! This certainly looks a lot better. Unfortunately, I think I am going about this all wrong. This is the end model goal, which I was trying to build based off the simplified model I showed Hyungsoo. Maybe I should back off and try a new tactic. Any suggestions, I can make a new post if preffered . Once again I have only very intro level knowledge of modeling and grasshopper.

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