Oceans cover about 71% of the earth’s surface and are responsible for several critical processes that sustain life on earth—such as producing oxygen, supplying food, and regulating weather patterns—and yet over 80% of the world’s oceans are unexplored and unmapped (National Oceanic and Atmospheric Administration, 2021). In part, this lack of exploration is because human divers can only reach a given depth before the pressure becomes too dangerous. Thus, to effectively understand and sustainably maintain the world’s oceans, we turn to technology such as autonomous underwater vehicles (AUVs), which can operate without oxygen and reach depths previously unavailable to humans.
On the surface, while much of the ocean is still an undiscovered frontier to us, there is virtually no place on earth untouched by marine debris, which is detrimental to aquatic life, chokes ecosystems, and contaminates water. While sustainable efforts to prevent more debris from going into the water exist, their impact is limited; most pollution comes from debris already in the oceans, and that debris must somehow be removed (Fulton et al., 2019). In an evaluation of marine litter robotic detection models, published by IEEE in 2019, researchers found that deep-learning-based object detection could plausibly detect marine debris in real-time, though the accuracy and interference rate of detection will differ depending on the model used. Moreover, an increase in the amount of available trash data would greatly benefit future research and detection model training. In solving this problem of marine debris detection (and eventual removal), the researchers also suggest the future investigation of multi-robot collaboration between multimodal robots.
- In an effort to increase the amount of information about the ocean in general, Liquid Robotics, a subsidiary of The Boeing Company that focuses on developing marine technology, has developed the Wave Glider: a marine robot that sits on the surface of the water and can collect ocean data for up to a year. The Wave Glider can also deploy a winch to collect data at a depth, as well, such as subsea acoustics, water sampling, and fish tracking.
- Having a similar approach as Liquid Robotics, Openoceanrobotics USVs (Uncrewed or Unmanned Surface Vehicles) are also equipped with sensors, cameras, and communication devices so that they can capture information from anywhere on the ocean and have instant access to it. Harvesting energy from the sun, these boats travel nonstop for months, without producing any greenhouse gas emissions, noise pollution, or risk of oil spills. These boats can monitor oil spills, detect intentional dumping, and aid in the cleanup effort.
- While not yet able to delve into the depths of the ocean to remove marine waste, there are several projects already underway targeting the collection of floating pollution from the surfaces of our water systems. RanMarine, a company founded and operating in Rotterdam, the Netherlands, has created WasteShark: an autonomous surface vessel that can collect 500 kilograms of surface debris (Biomass) in a single deployment while producing zero greenhouse emissions itself. Similarly modeled, the company has also produced the DataShark, designed to autonomously collect and collate water quality health data from waterways in any environment.
- Another operation, Clear Blue Sea, a nonprofit located in San Diego, California, is committed to innovating robotic solutions for removing plastic pollution from our water sources. The organization’s current solution, a Floating Robot for Eliminating Debris (FRED), has four prototypes to date, each operating similarly to the WasteShark. FRED runs on solar power, producing zero emissions; is semi-autonomous; can be customized to operate in many different marine environments; and collects marine waste with brooms, a conveyer belt, and a collection bin. The collected waste, upon the robot’s return to shore, gets sent to recycling centers for reuse.
- Furthermore, the French start-up IADYS (Interactive Autonomous DYnamic Systems) has developed Jellyfishbot: a remote-controlled, electric-powered, trash-collecting robot that has been deployed in 15 French ports, removing plastic bags, bottles, and other debris from narrow and otherwise unreachable nooks in harbors where waste tends to accumulate. The start-up is also expanding the Jellyfishbot’s capabilities to depolluting and decontaminating water systems by cleaning oil spills.
- On a smaller—but no less impactful—scale, the University of Bristol in the United Kingdom developed the Row-bot  in 2015: a project to create an autonomous robot that feeds off an organic matter in the dirty water it swims in, modeled after a water boatman insect. The Row-bot project aims to develop an autonomous swimming robot able to operate indefinitely in remote unstructured locations by scavenging its energy from the environment. When it is hungry, the Row-bot opens its soft robotic mouth and rows forward to fill its microbial fuel cell (MFC) stomach with nutrient-rich dirty water. It then closes its mouth and slowly digests the nutrients. The MFC stomach uses the bio-degradation of organic matter to generate electricity using bio-inspired mechanisms. When it has recharged its electrical energy stores, the Row-bot rows off to a new location, ready for another gulp of dirty water.
- The concept of Stanford University’s OceanOne, a humanoid diving robot, was born from the need to study coral reefs deep in the Red Sea, far below the comfortable range of human divers. It made its debut in 2016 in the Mediterranean Sea as it retrieved valuables from the La Lune shipwreck—which had not been disturbed since its sinking in 1664. The expedition to La Lune was OceanOne’s maiden voyage, and based on its astonishing success, it’s hoped that the robot will one day take on highly-skilled underwater tasks too dangerous for human divers, as well as open up a whole new realm of ocean exploration.
- Crown-of-Thorns Starfish (COTS) is a venomous and invasive species, as these starfish feed on coral reefs and are responsible for an estimated 40% of the Great Barrier Reef’s total decline in coral cover (Zeldovich, 2019). To solve this, researchers at the Queensland University of Technology in Australia developed the COTSbot and RangerBot, which can inject COTS with a fatal dose of bile salts—the same way teams of human divers also eliminate the starfish from the reef—with a 99% accuracy rate at detecting the starfish amongst the coral. Yet, the COTSbot was not designed to operate alone; rather, currently, it thins the field for human divers and has the potential to one day work in robotic swarms across the reef.
- Researchers at Harvard University are also looking into the role that soft robotics can play in capturing delicate oceanic creatures such as jellyfish and releasing them without harm with a Rotary-Actuated Device, or RAD (Brownell, 2019). The goal for the device is to one day be able to enclose the animal, collect cells and scan it to sequence its genome and print a 3D model back on the surface, and then let the animal go—all without greatly disrupting its natural state (Brownell, 2019).
 Row-bot: An energetically autonomous artificial water boatman, Philamore et al.(2015)
 Ocean One: A Robotic Avatar for Oceanic Discovery, Khatib et al.(2016)
 The Starfish Terminator, The American Society of Mechanical Engineers, 2018.