How Do Submarines Know Where They Are Going?
Light cannot travel through water, so how do submarines know where they are going? Periscopes are used to inspect their surroundings. They can be pushed up through the tower of a submarine. These devices are especially useful when they are just below the surface. Submarines can also use electronic equipment to navigate. GPS satellite navigation uses space satellites for their exact location. SONAR is a type of sonar that sends sound pulses into the sea to listen for echoes.
A submersible equipped with active sonar has an advantage over a diesel submarine in terms of speed. But the detection ranges of active sonar are larger than passive sonar’s. The SimKIT simulator is used to simulate a mover sensor discrete event. The simulation results indicate an exponential trend in initial detection time. Active sonar can also help track underwater vehicles. But the submarine’s speed advantage is not enough. The system must be able detect targets at greater distances.
Navigation with low drift and inertial
GNSS satellite signal navigation was the only way to navigate under water. However, GNSS cannot penetrate water and is therefore not suitable for use underwater. So, in order to make navigation underwater possible, inertial navigation systems have been developed for submarines. They allow the submarine to stay on course for long periods of time, and can also be used on space missions. But now, inertial navigation is not only for submarines – it is also used on manned space missions, such as the Apollo Lunar Module’s lunar landing in 1968.
While submarines have always been difficult to navigate, a virtual periscope can give the crew a glimpse of what they’re doing. It can be used when there isn’t enough sunlight or in the dark. This new technology is being developed by scientists at Technion Israel Institute of Technology. In an article published on the IEEE International Conference on Computational Photography, they explain the technicalities of this new technology.
Signature for passive broadband
When a submarine is in the water, it emits a distinctive sound called the passive broadband signature. This sound is generated by the propellers of a submarine. Cavitation refers to the formation of partial vacuums within a fluid. It is expressed as a pulsed sound. The cavitation sound can be detected at large ranges and is crucial in making submarines easily detectable by passive sonar. The speed and size of a submarine also have a major impact on its noise signature.
It is crucial to control depth underwater in a submarine. This requires careful planning. Changes in course are the most common problem. Changes in course can cause a moment of acceleration, decrease in speed, or change the direction of the sea. To control depth underwater, speed and trim must be adjusted for propellers. These control schemes were simulated in detail and compared with a traditional PD controller.