The Harvard Monolithic Bee is a millimeter-scale flapping wing robotic insect produced using Printed Circuit MEMS (PC-MEMS) techniques. This video describes the manufacturing process, including pop-up book inspired assembly. This work was funded by the NSF, the Wyss Institute, and the ASEE. Music: D-Song by Bonobo

See "Monolithic fabrication of millimeter-scale machines" and "Pop-up book MEMS":
https://micro.seas.harvard.edu/publications.html