Here is another drone that can inspect in hard to reach areas autonomously. This flying robot autonomously explored multiple ballast water tank compartments inside an FPSO vessel through manholes as narrow as 0.7 by 0.5 meters.
As the researchers explain:
the robot performs simultaneous localization and mapping, represents the world using voxels thus allowing it to conduct volumetric calculations, plans exploratory paths within each compartment, and detects and localizes the manholes within them.
During this mission, this drone explored 6 ballast compartments before returning to its take-off location.
[HT]