I like to crochet hyperbolic surfaces.
The technical difficulty with these surfaces is to crochet them without having to cut the plastic line, or cut it as few times as possible, These objects were each crocheted around two runs of plastic line.
For the interior shape I used thick line and for the waves around the perimeter the thinnest line.
The basic shape of this object is a curved diamond. I then crocheted six vertical hyperbolic axes in a triple wave.
This piece started as an ellipsoid. I then crocheted a band
spiraling around it from top to bottom. Eventually this band
became hyperbolic. Solutions to differential equations can look
Or the object could look like a seed pod.