Check out Lockheed Martin's robotic blimp inspector
 

Lockheed Martin's hybrid airships are as big as a football field, and it's a huge challenge making sure their surfaces are don't have tiny pinholes in them. That's why the company developed a robot called Self-Propelled Instrument for Damage Evaluati...

https://www.engadget.com/2016/07/27/...r-blimp-robot/