Collapsible rotifer

John Harris first described bdelloid rotifer in 1696 as "an animal like a large maggot which could contract itself into a spherical figure and then stretch itself out again"

Rotifers are one of the most common animals on our planet, yet we don't see them because they are really tiny: only 0.1-0.5 mm in length! They are harmless to humans as they can only filter feed on bacteria and other microorganisms.

This 3D model is a tribute to these fascinating creatures and it excels at imitation of their locomotion as well. You can see the two real rotifers captured using this microscope:

You can notice that the end of the rotifer's tail here is not bifurcated, like the real one would have, but instead, there is a hole that can be used to hang the model in stretched state. I wouldn't recommend hanging it from a backpack, unless you really trust the layer adhesion of your print setup.

This model was printed on a basic Ender 3v2 printer, so it is super simple to print:

• Layer height: 0.2

• Walls: 3

• Bottom layers: 3

• Top layers: 3

• Infill: Lightning 25%

• Brim: Optional, use it if you don't trust your bed adhesion

• Supports: None

After printing, you need to combine the two parts. Glue is optional!

One can scale the model up easily, but scaling down would require smaller nozzle diameter. In general, try to keep at least 2 walls on the thinnest parts for rigidity of the print.

Changelog:

• v1.0: Initial version with remesh modifier

• v1.5: Better, lightweight geometry, some problems with water-tightness

• v2.0: Fixed obvious problems with water-tightness, added 3D printable cilia

If adding some funny features, like hands would be interesting to you, tell me in the comments!

Stay tuned!