Trying to figure out the geometry of an inflated plastic bag:

Pillow shape generated with Kangaroo (+Grasshopper + Rhino).

Below is a digitized (inflated) plastic bag analyzed in Rhino.

Daniel Piker (Kangaroo Physics) says:

“Turns out the mathematics of it [pneumatics] is ridiculously simple. For any triangle the pressure will be the vector cross product of 2 of its edges.”