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ARTICLES FROM BACK ISSUES OF UNDERWATER MAGAZINE 
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James Pearl and Craig Winegarden bring us up to date on new developments in the field of underwater vehicles and atmospheric diving suits, and how they are utilized by some of our most respected scientific institutions.
Over the past few years, most new ROV technology has been coming from the oil and gas industry, where vehicle developments have opened new avenues for exploration and development in the push into deeper water. What has been overlooked, at least in the popular media, is the scientific application of deepwater vehicles. We currently know more about deep space than the deep ocean. However, the development of deepwater remotely operated vehicles (ROVs), autonomous underwater vehicles (AUVs), and atmospheric diving suits (ADS) is allowing scientists to explore and learn more about the deep ocean than previously possible. Harbor Branch Oceanographic Institute, Monterey Bay Aquarium Research Institute, and Woods Hole Oceanographic Institute are conducting some of the world's major scientific underwater studies.
Monterey Bay Aquarium Research Institute MBARI's first ROV, Ventana, was built by International Submarine Engineering and delivered in 1988. This ROV, rated to 6,070 feet (1,850m), is used for day expeditions into the canyon and typically runs four missions per week. ROV Ventana has also been used on extended missions to the Eel River Basin (off Northern California) and Santa Barbara. ROV Ventana has completed more than 1,800 research dives, enabling MBARI scientists to study midwater and benthic ecosystems, drill for rock cores along canyon walls, record observations of new species, deploy instruments, and collect specimens. Using their experience with Ventana, MBARI scientists and engineers designed and built a second-generation ROV system called Tiburon. The electric-powered vehicle was built for extended operations down to 13,123 feet (4,000m). The ROV has modular mission-specific toolsleds for benthic, midwater, and geology applications. MBARI engineers integrated scientific sensors and data logging equipment into the core of the unit and designed the computer hardware and software architecture. Tiburon has completed nearly 200 missions, including novel deepsea CO2 chemistry experiments, first observations of offshore seamounts, gas hydrate experiments off Northern California, and geochemical studies on the Juan de Fuca Ridge off Washington. When the ships are in Monterey Bay, live video images from both vehicles are transmitted to shore via a microwave connection. A special program at MBARI's sister institution, the Monterey Bay Aquarium, allows visitors to "look over the shoulder" of scientists conducting real-time research in Monterey Bay via their Web site at www.mbayaq.org/efc/efc_se/se_exploring.asp. Snapshots are available on MBARI's site, www.mbari.org/cruises/both.asp. MBARI's ROVs have also been used to collect animals for display at the aquarium in its Mysteries of the Deep special exhibition, the world's largest exhibit of living deep-sea life. MBARI designs much of its mission-specific equipment in-house but also teams with industry when appropriate. It is also actively developing AUV technology under the lead of Dr. James Bellingham.
Harbor Branch Oceanographic Institute HBOI currently uses three ROV systems, all developed in-house to research the deep ocean. Two "fly-away" ROVs, which are inspection class systems used for film/TV production and search/identification tasks. The systems are designed for low-cost air freight and are rated to 1,000 feet (300m) depths. The third is the Rescue/Support ROV Panther, which is a 25-horsepower electro-hydraulic system complete with winch/TMS/LARS and control van. The system is rated at 5,000 feet (1,517m). The system supports scientific operations and acts as a rescue device for the Johnson-Sea-Link four-man submersible. HBOI started using ROVs to support science operations and act as a rescue device for manned submersibles in 1973 with the in-house developed CORD ROVs. Two of these systems were built and last saw service in search and recovery operations to locate components of the space shuttle Challenger. HBOI Engineering operates the Ocean Voyager I, which was built in cooperation with FAU in 1992. Jerry Neely, HBOI's Director of Engineering, says there are also plans to build a state-of-the-art deepwater AUV system for commercial and scientific surveys. "The system will include a control van, mission planning and monitoring software, mission data downloading and reporting software, deepwater tracking and navigation system, advanced through-water telemetry and video transmission, launch and recovery system, and will be built from off-the-shelf components," he says.
JAMSTEC's New Hyper Dolphin ROV The Hyper Dolphin is a 75-horsepower ROV and will be used by JAMSTEC for scientific missions that will include mid-water, benthic, and geological work. The vehicle system includes two ROVs, control van, launch and recovery system, and maintenance van. Each vehicle is fitted with two 7-function manipulators, an advanced studio quality HDTV Super HARP camera, as well as three other cameras, sonars, HMI lights, and a sample basket. The Hyper Dolphin control van contains a state-of-the-art custom-built control console complete with pilot and navigator touch screens, digital VCR recorders, large flat screen plasma displays (two 50-inch and four 42-inch), and raised theater seating for scientific observations. Traction and storage winches, hydraulic power unit, belly pack, spares, and manuals in Japanese complete the system. These vehicles add to the list of over 200 ROV systems ISE has built in its 25-year history. ISE is equipped with the facilities to submergence test the vehicles at its Port Coquitlam location. Once the submergence tests are complete, ISE uses its 75-foot (33m) long barge, the ISE Researcher, for sea trials in the waters surrounding Vancouver.
Woods Hole Oceanographic Institute The Jason ROV, named for the Greek hero who searched for the Golden Fleece, was developed in-house by WHOI in 1991. It is the only ROV specifically designed for scientific operations to 18,000 feet (5,460m). Soon after development, Jason became part of the National Deep Submergence facility. On any given research project, WHOI uses Jason for detailed survey and sampling tasks. Woods Hole also developed a smaller ROV system, Jason Jr., that was operated from Alvin during the Titanic exploration in 1986. The scientific community has led the development of the AUV, which is just now beginning to make its way into the commercial realm. AUVs are untethered systems that are preprogrammed to go down and carry out specific duties, allowing scientists to collect data without having to be present. This torpedo-like system can cut costs by reducing the amount of supervision needed to operate the vehicle and can be launched from smaller vessels. One of the leaders in the development of the AUV is WHOI, which has developed two systems. The first, called REMUS, is used for research in 450 feet (137m) of water or less. The main purpose of the REMUS AUV is to record salinity, height off bottom, current speeds, temperature, water depth, and sonar scans. WHOI currently has ten of these vehicles in use. The latest AUV developed by WHOI is the Autonomous Benthic Explorer (ABE). Three meters long and capable of 15,000-foot (4,550m) dives, ABE was successfully tested at sea in 1995 and 1996. ABE is different from most AUVs under development in that it is designed for long-term monitoring missions and spends most of its time "asleep," attached to a simple hitching post near the area of interest. At regular intervals the ABE will "wake up" and, using an acoustic navigation system to guide its movement, travel around the survey area taking video snapshots and making a variety of measurements. At the end of the survey, the ABE returns to its hitching post and simply goes to sleep until the next scheduled survey. This sleep conserves energy and allows the ABE to stay down for as long as one year. The ABE was designed for a variety of missions, but foremost is monitoring geological and biological changes in hydrothermal vent regions. WHOI is currently using a combination of ABE, Jason, and Alvin on research projects. The combination of all three allows each to do a specific task. When all the data is combined, it produces a very detailed scientific analysis.
A Variety of Scientific Vehicles The major drawback with ROVs and ADS systems is that they have to be tethered, which is a hindrance in deeper waters. The deeper the work site, the greater the need for a larger umbilical. This causes drag and reduces the machine performance. In response to this problem, Phil Nuytten, father of the ADS, has invented what he calls the Directly Operated Vehicle, or DOV. His company, Nuytco Research, released the first of these vehicles last year. The DeepWorker 2000 is an untethered, one atmosphere, single-person submersible propelled by self-contained battery powered neodymium thrusters. A two-person version of the vehicle, the Dual Deepworker, is also available (see "Zegrahm Unveils Nuytten's Dual DeepWorker" in the May/June 2000 issue of UnderWater Magazine). The DeepWorker is capable of 2,000-foot (606m) depths and speeds of up to four knots. This machine takes the operator out of the control shack and puts him into the ROV. The pilot is actually at the work site and sees, hears, and feels what is happening, not what he thinks could be happening based on remote sensors. The DeepWorker 2000 is steered by foot pedals. The operator simply points his feet in the desired direction and away it goes! When compared to a work class ROV, the unit is low cost. It is modular and weighs one ton. Nuytten designed the Deep Worker around a business class airline seat and says he wanted it "to be able to fit in a half-ton pickup." The Sustainable Seas project, led by Dr. Sylvia Earle, is one of the first major scientific expeditions to use the DeepWorker 2000. DOER Marine Operations is responsible for training scientists to pilot the Sustainable Seas vehicles. This eliminates the subjective error by non-scientists in data acquisition. "DeepWorker's size and modular configuration allows deployment from any number of platforms, thus reducing the expense of a mother ship," says DOER Marine Operations' Liz Taylor. "The scientists and pilots that we have trained love the freedom of driving the subs themselves, allowing them to totally focus on their subject. During a recent Sustainable Seas dive, Dr. Earle spotted a rare deep ocean octopus at about 1,400 feet (425m). She was able to engage the creature for over an hour, obtaining video and still images while making behavioral observations. By piloting the sub herself, she was able to control the situation so as not to disturb the animal."
Adequate Training A Priority The scientific community is now running into the same problems. One of the major stumbling blocks for the scientific community is the inability to offer competitive wages. An experienced ROV technician/pilot can work for a major ROV contractor and make a great deal more money. This is creating a vacuum of qualified technicians and pilots in the scientific community. Another hurdle for most experienced deepwater vehicle operators to overcome is a lack of specialized marine scientific knowledge, which can create an inability to communicate with scientists. Knowledge of advanced marine technology is becoming an integral part of many ocean-related jobs today. Marine Advanced Technology Education (MATE) was formed in 1994 to address the need for quality marine technology education programs, and is sponsored by the National Science Foundation (NSF). The main purpose of MATE is to identify and address critical issues in marine technology education and recommend strategies for academia, industry, and government to deal with these issues. MATE has proposed a set of guidelines requiring that a marine technician: be knowledgeable about marine science, be able to communicate with scientists, have specialized knowledge, be a "doer," and know maintenance of equipment. These guidelines were developed through the use of questionnaires given out to the industry and educational facilities. MATE is currently working on guidelines for ROV technicians and other marine related fields. So what does all of this mean? All of the scientific research conducted by underwater vehicles is helping us with the understanding of the marine ecosystem. These vessels can bring specimens to the scientist or take the scientist to the creature's habitat. The ROV, ADS, DOV, and AUV are providing a window into this world without having to compromise the safety of humans. As technology grows, scientists will continue to push into deeper water, providing a better understanding of our planet. UW James Pearl and Craig Winegarden are recent graduatues of the Institute of ROVs in Houston, Texas.
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