A (remix of) a gripper based on the fin ray of a fish tail

This is a gripper that bend around the stuff you pick up. It is based on the principal of the fin ray of a fish tail. See also this video of a (bit too old and dry) fin ray of a tilapia fish: https://vimeo.com/22739805

This gripper can be handy too grip dirty stuff like money or garbage in times of the Corona and Covid crises.

This principal of the fin ray is also interesting for other applications like wings, sails, propellers, rudders, keels etc.
Remix of https://www.thingiverse.com/thing:3757806
Also check this:
Festo Japan: https://www.youtube.com/watch?v=byKm9vO_pvM&t=5s
Another remix: Gripper https://www.youtube.com/watch?v=90cXfaFM4O8
See also Fish Swimming, by John J. Videler, Chapter 3.3 Fin Rays, page 45, Chapman & Hall 1993, ISBN 0-412-40860-0.

Use PETG as PLA is not both so strong and flexible.
Do not clean with hot water as your print will deform.

The tests with "inbetweens" are too stiff.