Insect Drones.

The U.S. agency DARPA, e.g. the Defence Advanced Research Projects Agency has awarded in 2019 two multi millions dollars contracts to Honeywell International Inc. Automation and Control Solutions (ACS) division related to the Short Range Independent Microrobotic Platforms (SHRIMP) project.

The main reason for that interest is to build robots that are able to go where traditionally sized robots couldn’t go. Indeed, some situations prevent a ‘standard sized’ robot from entering some territory for a recognition mission or infantry situation awareness for instance.

Some territory may be under extreme surveillance by sophisticated radars that could detect any robot, ground, or aerial of a weight of one kilogram for instance, or even less.

Or some facilities could be entered only via extremely tiny canalizations of the size of a few centimeters.

Darpa is also known to have shown interest in tiny robotic insects as a way to improve the efficiency of the Microscale Biomimetic Robust Artificial Intelligence Networks that they are developing aka the Micro Brain project.