While we may have learned about our planet’s underwater habitats through the use of satellites, sensors and divers, such technologies merely scratch the surface of the ocean. Thankfully, over the last few decades, engineers have developed submersibles technology that are capable of meeting some of the challenges of the deep sea.
Aerial drones have infiltrated almost every aspect of the modern world, from photography and television news coverage, to environmental monitoring, surveillance, construction, agriculture, entertainment, archaeology, environment, etc.
Fortunately, for submersible drones (underwater drones), much of the technology developed for aerial drones are being adopted and adapted to work in a very different environment, such as underwater.
The following list will show 23 of the many ways that submersibles are being used beneath the waves, by oceanographic scientists, archaeologists, militaries, commercial divers, photographers, undersea explorers, and others.
Technology developed in aerial drones, such as greater levels of autonomy, are being adapted to submersibles. Autonomous drones are more like robots and less like remote-controlled devices. The question of whether to reinstitute shutdowns is a complex one, although they lack complete autonomy, very advanced remote-operated underwater vehicles, known as ROVs, have become the main submersible used in scientific and commercial underwater operations. These are used in undersea oil drilling projects and scientific research in the most severe environments in the ocean.
The Deepwater Horizon oil spill, in 2010, resulted in a gathering of the world’s largest robotic underwater armada, with as many as a dozen large “working-class” ROVs which struggled for months to stem the oil gushing from a shattered wellhead on the seafloor beneath 5,100 feet of water.
A very important lesson that was learned from this experience is that it is essential to make ROVs more autonomous, even when they remain tethered by an umbilical cable to a control ship on the surface. Advanced ROV’s, like the Schilling UWD, already uses pressure gauges, compasses and doppler sonar to stay oriented. By making ROVs more autonomous, they would be more aware of their surroundings. According to those who worked on the The Deepwater Horizon oil spill, “this is a feature that might have been useful navigating cables and moving gear in the Gulf.”*
Miniaturization has made support ships to operate an ROV unnecessary. Now ROVs are connected directly to an operator by long umbilical cables to carry out expert tasks like underwater inspections. This is significant progress because the electrical conductivity of saltwater, made radio communication very difficult underwater.
The Deep Trekker drone is controlled by a video-link handset that is able to be operated from the surface, or by a diver, in the water. When fitted with a multibeam sonar system, the drone can “see” in dark or murky waters, which makes it possible for scuba divers to search for shipwrecks in Lake Huron, as well as explore inside the wreck of the USS Arizona at Pearl Harbor in Hawaii.
The oil and gas industry are able to offer advantages that are already being put to work because of submersibles that are completely autonomous. Lockheed Martin’s yellow Marlin drone submarine has been used to inspect offshore rigs and underwater pipeline in the Gulf of Mexico, a sector that costs close to a billion dollars a year.
The Marlin is able to operate at depths close to 1,000 feet (300 m) and keep going for as long as 16 hours. The Marlin Mk2, which is an updated version of the drone, launched a Lockheed Martin Vector Hawk aerial drone and is featured in a U.S. Navy technology demonstration.*
Submersibles have been used to explore the most extreme depths of the world’s oceans. The Nereus was a hybrid of an autonomous drone, and a remote controlled ROV built by the Woods Hole Oceanographic Institution. The purpose of this hybrid was to explore Challenger Deep in the Mariana Trench near Guam, the deepest surveyed point of the world’s oceans, at an amazing depth of 35,768 feet (10,902 m).*
While the Nereus successfully reached the bottom of Challenger Deep in May 2009, it unfortunately was lost five years later, in 2014, while exploring the Kermadec Trench near New Zealand, at a depth of 32,500 feet (9,900 meters). The reason for the loss is that it imploded because of high pressures as high as 16,000 lbs. per square inch (psi).”*
Wave Gliders, which were developed by a California technology firm called “Liquid Robotics” are submersibles that have travelled further on our planet. In fact, these robots/drones have covered more than 1.4 million miles in the ocean. Each drone consists of a surfboard-sized “float” and a wing-shaped “sub” that hangs close to 26 feet (8 meters) under the water. What enables these submersibles to travel thousands of miles at sea without fuel, is the use of “wave motion and solar power with applications in environmental monitoring, defense,s and maritime surveillance, and offshore oil-and-gas operations.”*
Autonomous ocean gliders, or underwater gliders, like the Slocum Gliders, are able to convert small changes in buoyancy into forward motion. They are “used extensively for scientific research at sea, such as remote water sampling, environmental monitoring, or acoustical surveillance over months and thousands of miles of ocean.”*
In 2016, ocean gliders, equipped with microphones, recorded the mysterious “Western Pacific Biotwang,” which researchers think may be “the call” of a minke whale, the call that has never been heard before.
Experts anticipate the day when a fleet of underwater robots will be mapping the floors of the oceans, lakes and rivers, similar to how Google has mapped the streets.
Submersibles have already been used to map important underwater sites. In 2015, the Sirius AUV was used to map the Antikythera Mechanism, which was found, along with other treasures.
Fly & Dive
The idea of having drones that can both fly and dive may seem outlandish, but there are numerous applications for such capability. The ‘Naviator’ drone is being developed by a team at Rutgers University School of Engineering, which expect it to be used to inspect bridges, both above and below the water, for search and rescue operations.
In addition, such a versatile drone can also evaluate seaborne environmental incidents, such as oil spills or algae blooms, as well as, do research into wildlife species, like whales, that spend time both above and below the waves.
South China Sea Drone Drama
In December, 2016, a Chinese warship seized an underwater autonomous drone deployed by a US Navy oceanographic research vessel, the USS Bowditch, in the contested South China Sea region.
According to news reports, the crew of the Bowditch were about to recover the drone after its mission, when it was picked up by a Chinese warship instead, but they did return the drone to the U.S. Navy a few days later.
I 2018, the U.S. Navy created its first dedicated underwater drone unit:
“Unmanned Undersea Vehicle Squadron One, or UVRON 1 for short. The US Navy sees underwater drones eventually being used in ‘every spectrum’ of naval operations, from mine hunting and surveillance to humanitarian assistance and scientific research.”*
Civilian contractors for the U.S. Navy is securing a Kingfish underwater vehicle, which can use side scan sonar to search for and investigate suspected naval mines and other objects of interest, floating, or on the seafloor.
Experimental Naval Drone
The U.S. Navy’s Naval Undersea Warfare Center (NUWC) has developed its Manta submersible as a modular test for autonomous underwater drone technologies. The Manta UUV is over 30 feet long and carries a payload of almost five tons. It has torpedo weapons, acts like a mother ship, which can include additional smaller submersibles.
The U.S. Navy is also funding research into advanced submersible concepts, like the swimming “Mantabot,” which was developed at the University of Virginia, and uses silicone fins for swimming, based directly on the cow-nosed ray, a species related to mantas.
The swimming technique and streamlined shape of the drone makes it possible to move quickly and smoothly through the water using relatively little energy. This is important for submersibles because it enables them to function at sea for long periods without recharging.
Naval Drone Swarms
The UK Parliament considered whether to modernize or scrap its Trident nuclear missile subs by warning that advances in drone technology could soon make submarine warfare obsolete.
This is an amazing consideration!
The rationale is the following:
“The report warned that swarms of cheap robot sub-hunters could blanket the oceans with acoustical and other sensors that could negate a submarine’s ability to travel undetected underwater.”*
In addition, the U.S. Navy has also experimented with autonomous robotic drones to guard U.S. ships and swarm enemy vessels.
The world’s navies are not the only ones interested in swarms of submersibles, as scientists are as well. Researchers at the University of Ganz, in Austria, have developed the “CoCoRo” swarm of more than 40 underwater robots to research how they can act together as a team to accomplish various tasks underwater.
The autonomous drones in the “CoCoRo” swarm, use flashes of light to communicate, and come in three different types, depending on their function.
Plankton Mapping Swarms
Scientists have also used swarms of submersibles to investigate environmental events, such as plankton mating.
At the University of California-San Diego, researchers built a swarm of 16 autonomous submersibles and dropped them off the coast, and they were programmed to stay at a depth of 33 feet, and to map the “internal waves” that enable the plankton species to mate.
Floating Sensor Networks
Hydroswarm is a technology company that builds thousands of pumpkin-shaped underwater drones to map the oceans and act as a surveillance system for everything from oil pollution to illegal fishing to drug smuggling.
The Ellipsoidal Vehicle for Exploration (EVE) submersibles, was developed by Sampriti Bhattacharyya, a mechanical engineer at the Massachusetts Institute of Technology (MIT). Bhattacharyya says the EVE submersible is designed to be used independently, or as part of a swarm of underwater drones, that could create a Google Maps for the oceans.
Underwater Robot Miners
Submersibles that were designed to work in dangerous places, such as flooded mines, were tested at a china-clay pit in the UK in 1918.
The EU-funded Viable Alternative Mine Operating System (VAMOS) project developed three types of submersibles to extract minerals from abandoned, flooded mine sites considered too hazardous or costly to access.
Mines, deeper than the local water table, usually fill with water unless they are pumped out. Eventually they are abandoned and completely flooded. According to developers, it makes more sense to reopen an existing mine with robots, rather than excavate a new pit.
Drones Under the Ice
Submersibles are used by scientists to explore some of the most remote regions of the oceans, beneath Antarctica’s ice shelves, including the coldest waters on earth, where the temperature is a few degrees below the normal freezing point because of the salinity of the seawater.
The measurements provided by submersibles, enable scientists to accurately estimate the total amount of algae growing on the ice, which is an important source of food beneath the ice shelves in the ecosystems.
Wartime Wreck Search
As part of an effort to discover the final resting places of their crew, underwater robots have been used to search for the downed wrecks of American warplanes from World War II.
“Project Recover” uses a variety of new underwater technologies, including autonomous underwater drones equipped with sonar and cameras, to make a thorough and regular search of the ocean floor for wartime plane wrecks, which are often very difficult to spot.
In 2014, Project Recover divers, used drones to find two World War II warplanes in the islands of the Republic of Palau in the Western Pacific Ocean. In addition, they found two lost B-52 bombers, near Papua New Guinea, two years later, in 2016.
A non-profit group, called “Robots,” in Service of the Environment (RSE), is developing a submersible to hunt down and destroy “Asian Lionfish.” This was crucial because “Asian Lionfish” became a serious threat to coral reef systems in the Western Pacific, where they have no natural predators.
The deep-diving drone is guided by controllers at the surface, to track and close in on the invasive enemy that looks “fishy.” Before sucking them into a containment tube and stunning them with an electrical charge, one drone can humanely dispatch close to ten lionfish before returning to the surface with its catch.
Manta Ray Drone
The BOSS Manta Ray is an autonomous submersible developed by a German robotics company, Evologics, which specializes in aerospace and maritime robotics. The underwater drone is designed to mimic the manta’s flexible body, giving it the ability to control its depth very precisely with its large wings. It also has a “flapping” mode of swimming, which is very energy efficient, and it is also equipped with jet thrusters that gives it a high-speed mode.
Like Evologics, some other technology companies which make submersibles, are using biomimicry, which is an approach to technology that looks for ideas from nature.
Festo is a German engineering company that has developed its Aquajelly underwater robots to mimic the swimming motions of jellyfish. These submersibles can also communicate with each other, and, unlike real jellyfish, they can even coordinate their behavior.
While aerial drones have infiltrated every aspect of the modern world, submersibles have been making steady progress in descending into the mysterious depths of our planet’s great lakes, seas and oceans. This fact gives us confidence that the unexplored seas will continue to be explored at an accelerated rate. After all, so much of the resources of the planet have been virtually hidden under water until recent times.
It is fortunate that much of the technology developed for aerial drones are being adopted and adapted by underwater robots/drones.
We have seen 23 of the many ways that underwater robots/drones are being used beneath the waves, and it should give us confidence that the treasures of the deep will help mankind in its search for resources to better take care of this planet, and its people.