Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Deep Sea Technology Is Put To The Test In Campus Tank

22.11.2002


Photo A: Louis Whitcomb supervises underwater robotics research at Johns Hopkins, including a new lab that features a tank filled with nearly 43,000 gallons of water.
Photo by Jay Van Rensselaer


Photo B: Doctoral student James Kinsey prepares to test the navigation and control systems that guide the lab’s underwater robot.
Photo by Jay Van Rensselaer


Tethered Robotic Sub Helps Engineers Refine Computerized Navigation, Control Systems

In a new indoor tank filled with almost 43,000 gallons of water, Johns Hopkins engineers are developing and testing computer control systems to serve as the "brains" for some of the world’s leading deep sea robotic exploration vehicles. To promote advances in underwater robotics, the Whiting School of Engineering recently constructed the circular hydrodynamics tank, 14 feet deep and 25 feet in diameter, inside a large lab space within Maryland Hall.

In the tank, researchers are testing the JHU Remotely Operated Vehicle, a small underwater robot developed at the university. Its navigation and control systems, also developed at Johns Hopkins, have recently been adapted and enhanced for use in the much larger Jason II vehicle, a new deep-sea oceanographic research robot operated by the Woods Hole Oceanographic Institution. The Johns Hopkins navigation program also has been deployed aboard the Deep Submergence Vehicle Alvin, Woods Hole’s inhabited oceanographic submersible.



Future navigation and control techniques devised in the new test tank are expected to improve the operations of deep-sea robots such as Jason II and Isis, a similar vessel that Woods Hole is developing for the University of Southampton in the United Kingdom.

"Our research goal is to develop new technology to enable new oceanographic research," says Louis Whitcomb, associate professor in the Department of Mechanical Engineering, who is director of the new testing facility. "Moreover, we collaborate with other institutions like the National Deep Submergence Facility at Woods Hole Oceanographic Institution to deploy these new technologies for ocean science on vehicles such as Jason II and Alvin."

Deep sea robots like Jason II are relatively new but increasingly important tools for scientists who want to explore some of Earth’s most remote and hostile frontiers. Human scuba divers can descend safely only about 300 feet, or 100 meters. Yet the deepest parts of the ocean lie 11,000 meters below the surface. To explore greater depths, scientists in the 1960s began building small inhabited submersibles. Such vessels have been used to explore the R.M.S. Titanic’s wreckage. But because such vehicles must carry their own fuel and air supplies, explorers are limited to eight to 12 hours per dive.

To overcome these limitations, engineers in the last 15 years have begun building uninhabited robotic vehicles that remain tethered to a research ship on the surface. Long cables feed power and instructions to the submersible and retrieve images and other data. These vehicles usually are equipped with video cameras to allow researchers to see what the vehicle "sees" in real time. They often possess robotic arms to collect artifacts, rocks and biological samples.

"The deep ocean is a cold, dark, high-pressure, inhospitable environment, and this equipment must be able to operate reliably under these conditions," Whitcomb says. "Inhabited deep submersibles, such as the U.S. Deep Submergence Vehicle Alvin, remain the only way for humans to directly observe the benthic floor with their own eyes. Deep-diving submarines are ideal for many tasks, yet they have limited endurance. One advantage of an uninhabited submersible is that it can explore the deepest parts of the ocean 24 hours a day, seven days a week, under the remote control of science teams that are working around the clock aboard the mother ship."

Operating a robotic vehicle from a great distance poses certain challenges, however, and that’s where Whitcomb’s team comes in. "Our lab focuses on two key problems that occur in the design of remotely operated undersea vehicles: navigation and control," Whitcomb says. "One of the most difficult things about maneuvering an underwater vehicle is that you need to know where it is. What, precisely, is its position and orientation on our planet? To determine these things, we’ve developed a computer system that integrates signals from a dozen on-board sensors to compute the submersible’s position and velocity."

Based on this information, an operator on the surface can use a joystick to move the undersea robot in three dimensions. The control system developed by Whitcomb and his students also allows an operator to tell a computer precisely where the vehicle should be located; the software then automatically moves the vehicle to that point. At the new Johns Hopkins hydrodynamics lab, researchers are fine tuning this system by sending commands over a tether line to six electric thrusters mounted upon the test submersible.

At sea, researchers on the surface can use this same system to carefully control a larger underwater robot’s movements, instructing the vehicle to move in a precise grid pattern. This allows the sub to collect the images and sonar data needed to produce photographic and topographic maps of sections of the ocean’s floor that contain interesting geological, biological or archaeological features. Whitcomb says his computer system also can direct a submersible to hover just 6 to 12 inches above the ocean floor, close enough to collect samples without disturbing ecologically sensitive surfaces. "With this system," he says, "we can control a vehicle’s position to within a few centimeters and its heading to within a degree."

Whitcomb supervises underwater robotics research at Johns Hopkins as director of the Dynamical Systems and Control Laboratory. The JHU Remotely Operated Vehicle was designed and built by one of his doctoral students, David Smallwood. Another of Whitcomb’s doctoral students, James Kinsey, is refining the underwater navigation system at the new testing tank. Other Johns Hopkins marine and oceanographic researchers will have access to the new tank. Funds for construction of the tank and related research were provided by the National Science Foundation.

Office of News and Information
Johns Hopkins University
3003 N. Charles Street, Suite 100
Baltimore, Maryland 21218-3843
Phone: (410) 516-7160 | Fax (410) 516-5251

Phil Sneiderman | EurekAlert!
Further information:
http://www.jhu.edu/news_info/news/audio-video/underwater.html
http://robotics.me.jhu.edu/dscl/
http://www.me.jhu.edu/

More articles from Process Engineering:

nachricht Design treatment of advanced metals producing better sculpting
08.03.2019 | Purdue University

nachricht Laser Processes for Multi-Functional Composites
18.02.2019 | Fraunhofer-Institut für Lasertechnik ILT

All articles from Process Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The taming of the light screw

DESY and MPSD scientists create high-order harmonics from solids with controlled polarization states, taking advantage of both crystal symmetry and attosecond electronic dynamics. The newly demonstrated technique might find intriguing applications in petahertz electronics and for spectroscopic studies of novel quantum materials.

The nonlinear process of high-order harmonic generation (HHG) in gases is one of the cornerstones of attosecond science (an attosecond is a billionth of a...

Im Focus: Magnetic micro-boats

Nano- and microtechnology are promising candidates not only for medical applications such as drug delivery but also for the creation of little robots or flexible integrated sensors. Scientists from the Max Planck Institute for Polymer Research (MPI-P) have created magnetic microparticles, with a newly developed method, that could pave the way for building micro-motors or guiding drugs in the human body to a target, like a tumor. The preparation of such structures as well as their remote-control can be regulated using magnetic fields and therefore can find application in an array of domains.

The magnetic properties of a material control how this material responds to the presence of a magnetic field. Iron oxide is the main component of rust but also...

Im Focus: Self-healing coating made of corn starch makes small scratches disappear through heat

Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.

Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...

Im Focus: Stellar cartography

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.

A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...

Im Focus: Heading towards a tsunami of light

Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.

"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Laser processing is a matter for the head – LZH at the Hannover Messe 2019

25.03.2019 | Trade Fair News

A Varied Menu

25.03.2019 | Life Sciences

‘Time Machine’ heralds new era

25.03.2019 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>