“Complex underground settings present significant challenges for military and civilian first responders. The hazards vary drastically across domains that can degrade or change over time and are often too high-risk for personnel to enter.

The DARPA Subterranean or "SubT" Challenge seeks novel approaches to rapidly map, navigate, and search underground environments during time-sensitive combat operations or disaster response scenarios.”

Reminds me of this video

https://www.bitchute.com/video/Cfwdi3lAHspU/