Put this in a pb, but was mixed in with other stuff. It's a taxpayer-funded "challenge".

DARPA Subterranean Challenge

https://subtchallenge.com/

> THE PROBLEM

> Current technologies fail to provide persistent situational awareness of the diverse subterranean operating environments, including tunnels, urban underground, and cave networks.

> THE CHALLENGE

> …allow warfighters and first responders to rapidly map, navigate, and search dynamic underground environments

> PRIZES

> …compete for up to $2 million in the Systems Final event, with additional prizes available for self-funded teams