Ocean survey is conducted to measure various physical features of seas and oceans, such as water depth (which we will discuss here mainly), major navigable waterways, offshore drilling operations, and much more.
Let’s look deeper into water depth measuring Water depth is calculated by measuring the time taken by a sound wave to travel that depth. For this survey, specific ocean survey equipment is required. This equipment helps in knowing numerous things about the sea as per their functioning.
This equipment can be installed on autonomous underwater vehicles, remote underwater vehicles or crafts, etc.
Sonars, lidars, sound speed profilers, winches, GPS for surveys are some of its examples.
One of them, which we will discuss over here, is ‘winch.’
WHAT IS A WINCH?
In simple terms, a mechanical device used in pulling up and out of the wind or to adjust the tension of a tether (usually a fiber-optic tether called ‘umbilical’) is called a winch. When a flexible fiber-optic rope is wound onto a winch, it is then called an umbilical winch.
Role of Umbilical Winch Umbilical winch plays a vital role in the availability of subsea trenching spread. Hence it becomes crucial to look if it has any default that leads to failure.
Our winches are efficient, compact, and specially designed to operate underwater with up to 10,000 m depth.
ULTRA-SHORT BASELINE
Have you ever wondered how we position autonomous underwater vehicles at a very far distance?
You will get to know how it is done shortly.
There is a method of underwater acoustic positioning called ultra short baseline (USBL).
It consists of a transceiver ( mounted on a pole under the ship), a transponder on the seafloor or ROV, and a computer for calculation.
Through USBL, an acoustic pulse is transmitted, which is then detected by a transceiver which converts it into a range. An AUV or ROV that is kilometers away can be positioned with this range and distance measurement.
To understand its functioning much better, let’s dig a little deeper into some of the terms.
Underwater acoustic positioning
It is a system through which underwater vehicles and drivers are tracked and navigated using direction and acoustic distance measurement. Other than USBL, there are other methods through which underwater acoustic positioning can be done. Such as,
Long-baseline system(LBL)
Short baseline system(SBL)
GPS intelligent buoys (GIB)
However, for a high precision underwater performance, USBL is not sufficient enough when used alone. Thus, some combined designs are being brought into use.
Autonomous underwater vehicle
An AUV or autonomous underwater vehicle is used for different underwater missions, such as detecting submerged rocks or wrecks that can be harmful to commercial or other ships or vessels.
WHY IS IT IMPORTANT TO CONDUCT AN OCEAN SURVEY?
As mentioned earlier, an ocean survey helps to measure the physics of oceans and seas (their coastal areas too). These things are essential to avoid any risks before heading into an area for navigation. If the ocean survey has been conducted, we can know whether navigation is safe or not (for military or civilian populations).
Looking at the accuracy rate of ocean surveys, it has been found that a short-baseline (SBL) system gives more accurate results than an ultra-short baseline(USBL) system.
There are specific ships designed to conduct oceanic surveys which also can conduct seismic surveys.
Summing up Knowing about ocean surveys in a short article isn’t enough. There is a lot to study and calculate about this. We just figured out and explained a few terms related to ocean surveys and explained how they work.
Hope this article was helpful for you to understand some of the basics of an oceanic survey.
Dt Marine Winches and its rental equipments 