Capperpillar

This project was inspired by plastic waste recycling company, located in Saint-Petersburg, Russia. Those guys make longboards of melted HDPE lids. That's very dope. I do hand over waste for recycling, so I liked the idea, which initially belongs to my friend Ilya Lyndberg.



Credits: 
    Idea, script, art directing, lighting, camera: Ilya Lyndberg

    TD, pipeline, simulations, rigging, shading: Nikolai Prudov

    Sound design: Leonid Panov

The technical part was challenging, I had to involve procedural rigging and animation pipeline as well as dynamics processing of those animations. This was a great chance to utilize new KineFX framework in Houdini. 
To fix intersections of animated lids I used Bullet and some tricky constraint networks.

The main idea behind this is to create simple objects (i.e. sphere primitives) for each of the animated lid, feed them into RBD simulation as animated objects with disabled collisions and constraint actual lids to corresponding sphere.

 

Almost the whole thing is shown in this screenshot: 

The second part of the project is the caterpillar transformation which is shown as melting those caps.

This was done with the flip solver. Nothing very special here, except the custom stick/slide handling to prevent viscous fluid to stick animated colliders

The suction force was created with VDB, converted to gradient field and custom popwind dop, which was sampling that VDB.

The same thing is here:

The last part involves the vellum solver 😍 which is my favorite one in Houdini to be honest.

Presim of the board was made with the restblend dop and tetrahedral constraints. Then the hires board was deformed by lowres tet representation of it and finally the cocoon was simulated afterwards. 

The tricky part of this shot was to make work volume collisions for the flip sim. It didn't want to work at all, because of changing topology, another words you can't make vdb from open geometry. when it is closed - it's ok. So the solution was to scatter points at first frame, interpolate them to match the surface animation and finally drop vdbfromparticles sop. That gave a nice collisions.