From The Action Lab , and Action Lab Shorts.

Checkout the Creality K2 Pro here: https://store.creality.com/products/k2-pro-combo-3d-printer

3D spherical flexure joint by Jelle Rommers:
https://www.thingiverse.com/thing:4841850

https://www.sciencedirect.com/science/article/pii/S0141635921000726?via%3Dihub#appsec1

WYRD mechanism elephant: https://www.thingiverse.com/thing:3491887
BYU CMR: https://www.compliantmechanisms.byu.edu/