Cleaning robot

Cleaning robots are small ARC-made machines that wipe the floors in various levels in Doom Eternal, especially ARC facilities such as the Cultist Base or the ARC Complex. These robots cannot be interacted with and are only part of the environment, usually found moving in square paths around the perimeter of rooms where no enemies are present. It is unknown who designed them, but they were likely made to wipe up the blood left behind after cultist rituals conducted by ARC personnel.

Trivia
The cleaning robot is the only machine in Doom Eternal that both cannot be interacted with, and pose no threat to the player, their sole purpose being decoration.