Ba'ul drone
Ba'ul drones were devices used by the Ba'ul in their massive underwater stronghold. 

These free-floating weapons were deployed in 2257 when Saru beamed himself to the stronghold in order to confront the Kelpiens' oppressors. Initially incapacitated by a drone, Saru was able to disable several and use their components to create a transmitter to contact the  for rescue. ()
Military technology
Vehicles‎