New inflation simulation component (not Kangaroo)

Jan 27 2020 Update
Added many new features! Including profile customisation. See details below.

Simulation Intro
Function: Feed a closed curve, it returns a inflated surface with inflating animation.

  1. N(Framei) is current animation frame. Use Smooth Numer for animation effect. Right click to set duration.
  2. N(FCount) for total number of animation frames.
  3. BaseCrv can be spatial or flat curves, but must be CLOSED! For BaseCrv is POLYLINE, set N(u)=0.
  4. N(u) for number of control points on equator direction. For BaseCrv is POLYLINE, set N(u)=0.
  5. N(v) for number of control points on profile diretion.
  6. Increase N(Crease) for boarded crease.
  7. Increase N(TopFlatten) for flatting top.
  8. Set inflation side: Back/Front/Both.
  9. InflateHgtMin sets start height of inflation through whole animation.
  10. InflateHgtMax sets end height of inflation through whole animation.

This component is made by Jia Zhuang. All right reserved.

Download: InflateSimulation.ghx (205.3 KB)


Hi all,

Here is a new inflation simulation component. Load a closed curve into “BaseCrv”, it gives an inflated balloon surface, and it is untrimmed! Use “Smooth number” to view animation effect.

Welcome everyone to explore the component and leave your comments.

Jia Zhuang


Now pin the equator to the input curve, or else it’s not engineering quality useful.

Thank you for your feedback. For you question, try increase N(u) input.

N(u) is an int for how many points to describe the input curve. It is possible leave the original curve not touched, but I didn’t expend the option in this version.

The component should support spacial curves as well. I haven’t do much test on them.

Try 3d curves. Quite a fun to play with.

This looks great. Thank you for sharing, I had been experimenting with inflation in Kangaroo2, and I look forward to having a play with this.

thanks for this great component! very useful – one suggestion: It would be awesome if one would have more control over the “stretchiness” of the foil. Here are two extremes, in first one the curvature is accumulated in the middle and in the second more at the edge

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Hi Jia Zhuang,

There is a lot that is great about this, Thank you.
It seems to have difficulty with corners in the input curve, both internal and external are missed, and they are leading to creases in the inflated shape.

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Can you upload your files?
My test of sharp corners is fine.

Thank you for your suggestion. I added more options. Now can customise profiles, and support polylines.
InflateSimulation.ghx (175.0 KB)


Hi Jia Zhuang,
Thank you for your reply, here is a simplified GH file that shows the problem with a rectangle.
It is based on the first file you uploaded.
DrewInflateSimulation corners Drew.ghx (150.4 KB)

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Thank you for your feedback. I updated my component, your crv is working now. please check the new file. InflateSimulation.ghx (200.2 KB)

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Thank you for your feedback and support. A new version is uploaded. Many new features are added. Please check the main post.

Thank you! nice update. One question: does your component basically use a rail revolve to create the surface? like this gh script:

railrevolve gh (9.0 KB)

Because I’ve noticed a problem when the profile is rotated around a sharp corner. The curvature is pushed upwards and “gives rise” to these lumps on the top of the surface. Because of this I don’t use railrevolve for these kind of surfaces and construct them mostly by hand…

A true inflated surface will become more spherical (/ parabolic I guess) at the top - maybe this could be achieved with some kind of cv-pulling? Just my 2 cents - thanks again!

Not really using revolve nor rail. I used loft.To create a roundish top, the profile lines are spatial, not planner.

ok- good to know. The orange example shows on the left a inflated foil with kangaroo on the right one created with your plugin. Maybe this should have been a bit clearer. In my case these bumps are not preferred, eg imac:

I think if you would smooth the loft curves from outer to inner :

the spikes in the corners could be avoided. What do you think?

It is smooth from out to inside. But one different for iMac, the top is not closed to one point but a planner surface. I made some modification on the simulation to achieve that.
InflateSimulation.ghx (289.6 KB)


can i ask how to describe the inflatable like this shape?