Remotely operated underwater vehicle

A remotely operated underwater vehicle (ROUV) or remotely operated vehicle (ROV) is a free-swimming submersible craft. These underwater machines are operated by people from the surface, usually in a control room, allowing them to explore the deep ocean without putting humans directly in harm's way. ROVs are used for underwater observation, inspection, and performing tasks like operating valves and other hydraulic functions, especially in the subsea oil and gas industry.

ROVs can carry special tools to complete specific jobs, such as connecting underwater pipes or replacing parts. Because they can reach depths that most submersibles and divers cannot, they are important for both research and commercial work. Whether in military, scientific, or industrial use, ROVs help us understand and work in the challenging environment of the deep sea.

Description

ROVs, or remotely operated underwater vehicles, are special machines made to work underwater, where it is very deep and dark. Unlike cars or airplanes that use radio signals, ROVs need a strong cable to connect them to people on a ship above. This cable sends power and shows pictures and information back to the people controlling the ROV.

These vehicles are very good at moving around and can do jobs like checking pipes or fixing things far below the ocean's surface. They often have cameras and lights, and sometimes they have extra tools like arms or sensors to help them explore and work in the deep sea.

Classification

Remotely operated underwater vehicles (ROVs) are grouped by size, weight, and what they can do. Small ROVs, called Micro-class, weigh less than 3 kg and are used where divers cannot go, like inside small pipes. Mini-Class ROVs weigh about 15 kg and can be carried and used by one person from a small boat.

Larger ROVs are used for more complex tasks. Inspection Class ROVs gather data and images, while Light Workclass and Heavy Workclass ROVs, which can weigh up to 220 horsepower, are used for stronger tasks at greater depths. Some very strong ROVs used for laying cables can work at depths up to 6000 meters.

History

In the 1970s and '80s, the Royal Navy used a remotely operated submersible called "Cutlet" to recover practice torpedoes and mines. The first ROV was developed in 1953 by Dimitri Rebikoff and was later improved because of interest from the navy. The U.S. Navy funded early ROV technology in the 1960s, which helped create tools for deep-sea rescue and recovering objects from the ocean floor.

ROVs became very important in the 1980s for offshore oil and gas work, especially when human divers could not reach deep enough. They are now used for many tasks, from inspecting subsea structures and pipelines to helping build and repair underwater oil fields. ROVs have also helped discover and study historic shipwrecks, like the RMS Titanic and the Bismarck. Besides oil and gas, ROVs are also used by the military and scientists for various underwater jobs.

Construction

Work-class ROVs are built with a large flotation pack on top of an aluminum chassis to help them stay afloat while performing tasks underwater. The construction of the aluminum frame can vary depending on the design of the manufacturer. Syntactic foam is often used for the flotation material. By placing lighter parts on top and heavier parts on the bottom, these ROVs stay stable and stiff while working underwater. Thrusters help control the ROV’s movement and position, especially in areas with strong currents.

ROVs are equipped with cameras, lights, a tether, and controls so they can perform basic tasks. They can also have extra tools like manipulators and sonar, depending on what they need to do. Most work-class ROVs follow this design, but smaller ROVs can look very different, depending on their specific job. Larger ROVs are often used from ships and may have special skids to help them get back on deck.

Configurations

Remotely operated underwater vehicles (ROVs) come in three main types, each with its own strengths and weaknesses. The first type is the open or box frame ROV, which looks like a cage with all its parts enclosed. This design works well for swimming freely in light currents but isn’t good for being pulled behind a ship because it doesn’t move through water smoothly. Most strong work-class ROVs use this design.

The second type is the torpedo-shaped ROV, often used for gathering data or checking things under the water. This shape moves easily through water but can be tricky to control, especially at slow speeds. It’s sometimes called a “tow fish” because it’s often pulled behind ships.

Tether management

ROVs need a tether, or umbilical, to send power and data between the vehicle and the surface. The tether’s size and weight matter: one that’s too big can slow the vehicle down, while one that’s too small might not be strong enough.

The tether is usually spooled onto a tether management system (TMS). This system helps keep the tether from getting tangled or knotted and can also act as a winch to lower or bring the vehicle back up.

Applications

ROVs are used for many important jobs under the water. They help check pipelines, look at ships, and map the sea floor. Even though they are smaller than some other ROVs, they can carry lights, cameras, and special tools to see clearly and find their way.

ROVs are also used to help filmmakers explore deep and dangerous places that people can't reach. They have been used in many exciting documentaries and TV shows. With more people interested in the ocean, making small ROVs has become a fun hobby for many.

Science

ROVs are important tools for scientists who study the ocean. They help researchers discover and observe deep-sea animals and other organisms in their natural habitats. For example, ROVs have been used to study the jellyfish Stellamedusa ventana and the eel-like halosaurs.

In the US, advanced research is conducted at places like the Monterey Bay Aquarium Research Institute (MBARI), the Woods Hole Oceanographic Institution (WHOI), and the University of Rhode Island / Institute for Exploration (URI/IFE). In Europe, the Alfred Wegener Institute uses ROVs to explore the Arctic and Antarctic seas. These vehicles are equipped with special tools like cameras, sensors, and manipulators to collect data and samples from the deep ocean. ROVs are also used in underwater archaeology projects, such as exploring shipwrecks.

Education and outreach

The SeaPerch Remotely Operated Underwater Vehicle (ROV) educational program helps students from elementary to high school build simple underwater vehicles using materials like polyvinyl chloride (PVC) pipe. This program teaches basic ideas about ship and submarine design and introduces concepts in naval architecture, marine, and ocean engineering. It is supported by the Office of Naval Research and managed by the Society of Naval Architects and Marine Engineers.

ROVs are also used in educational projects like the Mardi Gras Shipwreck Project, where an old shipwreck was studied and artifacts were collected for display. The Marine Advanced Technology Education (MATE) Center uses ROVs to teach students about ocean careers and improve their skills in science, technology, engineering, and math through an annual ROV competition. This competition features teams from around the world designing and building their own ROVs to complete various underwater tasks.

Military use

ROVs have been used by many navies for many years, especially for finding and dealing with underwater mines. In 2008, the U.S. Navy improved its rescue systems with a new modular design that includes a special tethered vehicle for submarine rescues. They also use an ROV called the AN/SLQ-48 Mine Neutralization Vehicle for mine warfare. This ROV can travel far from ships and reach deep water, equipped with different tools to handle mines.

The U.S. Navy’s ROVs are found only on certain mine countermeasures ships. These vehicles help with various underwater inspection tasks, including finding explosives, checking weather conditions near ports, and gathering important information for security. As these tools become more advanced, more navies and coast guards around the world are using them for safety and inspection work.

Public Safety

ROVs are also used by law enforcement and public safety teams for finding evidence underwater, recovering victims, responding to disasters, checking safety conditions, and helping with salvage operations. These vehicles are often used before human divers go underwater to make sure it’s safe. As demand grows, many agencies are getting funding to buy these ROVs, and some have even created special units just for operating them.

Specific vehicles

Some special underwater robots, called remotely operated underwater vehicles (ROUVs), are used for different jobs deep in the ocean. Examples include the Echo Ranger, a marine robot built by Boeing, and the Global Explorer ROV, which helps scientists study deep water. Others, like the Nereus (underwater vehicle), can work either with help from people above or on their own. These amazing machines help us explore and take care of our oceans.