This sounds like it's probably the sonar system of a submarine.
sonar is a device for detecting objects underwater by emitting sound waves and analyzing the echoes that bounce back. It is commonly used in navigation, fishing, and underwater mapping.
A blind man's cane is typically called a "white cane." It is a mobility device used by visually impaired individuals to navigate their surroundings by detecting obstacles and providing tactile feedback.
radar
A periscope.
In 1915, Paul Langévin invented the first sonar type device for detecting submarines called an "echo location to detect submarines" using the piezoelectric properties of the quartz.
A standard viewing device used on a submarine is a periscope.
Ballast tank
e-nose
None. The megapixels are in the detecting device. e.g. a camera, a CCD device.
A device for detecting underwater objects is typically called a sonar device. Sonar uses sound waves to detect and locate objects underwater by measuring the time it takes for the sound waves to bounce off the object and return to the device.
By an electronic device called 'sonar' .
ASDIC