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Blazing trails in underwater technology:
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Tucked away in a corner of an old marine sciences lab on a spit of land jutting out into St. Petersburg's Bayboro Harbor is the University of South Florida's Center for Ocean Technology, a research and engineering enterprise with big ambitions for a shrinking world. The center was created in 1995 to support the university's oceanographic research by designing and producing research instrumentation. Since then, it has grown from a nucleus of five scientists and engineers to more than 60, fueled by military and Coast Guard contracts for environmental sensing and scanning devices that have applications ranging from homeland security and drug interdiction to protecting troops abroad. And while primary funding comes from military sources, the applications are promising for environmental scientists. Staff members bring expertise in electrical, optical, chemical, mechanical and software engineering to the difficult task of designing technology for harsh underwater environments. The focus has been on developing an array of marine sensors capable of providing realtime analysis of environmental pollutants and microscopic sea life. Instruments are housed and transported in autonomous underwater vehicles (AUVs) resembling miniature yellow submarines, five to seven-feet long. The fiberglass AUVs can be tethered and towed behind ships or deployed with pre-programmed directions. COT also designs stationary research platforms capable of hightech surveillance. Its Bottom Stationed Ocean Profiler, or BSOP for short, sits underwater to escape detection and can be outfitted with chemical, biological and physical sensors, along with tiny cameras, that feed information via satellite to shore. Currently undergoing testing, BSOP can be used for security, drug interdiction or spotting ships engaged in illegal dumping. The device might be programmed to pop up for observation at set intervals or in response to certain stimuli, such as wave action from a fast-moving boat. The center is credited with building the world's first underwater mass spectrometer, a device capable of measuring a vast array of environmental pollutants, like chloroform, benzene and xylene, down to parts per billion. In-situ underwater mass spectrometry, coupled with advances in AUV technology, has the potential to revolutionize environmental monitoring, says USF scientist David Fries. "We envision this evolving to the point where we have networks of systems capable of tracing chemicals, both natural and manmade, back to their sources." Before instruments ever leave the lab, they are tested in a giant, 9,000-gallon water flume where engineers can mimic ocean conditions by varying salinities. COT has its own machine shop, electronics and chemical labs, and dark room. In the optics arena, the center is developing underwater microscopes with high-resolution cameras that can take 3-D images of microscopic plants and animals at the base of the food chain. Oceanographers are using the optics devices to study the abundance and variety of plankton in the ocean. Yet another of COT's pioneering creations may eventually be deployed by the Navy to scour the ocean bottom for mines buried below the sediments in near-shore waters. The ROBOT, or Real-Time Ocean Bottom Optical Topographer, is equipped with a laser scanner that traces the contours of the sea bottom to create a 3-D or topographic picture. "Putting things underwater is exceedingly difficult," says COT Business Manager Carole Steele. You have to keep the instruments dry, but also devise ways to expose sensors to the water, while battling corrosive elements like salt water and withstanding intense pressure. "The further you go down, the more inhospitable the conditions," Steele adds.
It's a small world after all Not only is the technology rugged, the sophisticated instruments are getting smaller and smaller, part of a technological revolution expected to transform businesses and households around the globe. At the heart of the revolution is MEMS, or microelectromechanical systems. MEMS refers to a broad class of sensors and systems that utilize functional devices such as gears, hinges, switches and levers with tiny parts that are invisible to the naked eye. These miniature marvels are fabricated using techniques similar to those used to make silicon computer chips, except that MEMS devices can be constructed on various substrates, including glass and plastic, increasing their flexibility. The applications are limited only by the imagination. Scientists envision:
"If we can package the technology for the inhospitable saline environment of the ocean," says Steele, "we can probably make it work in the harsh inner-space environment of the human body." USF Associate Researcher Sean Knighton sums it up this way: "If you can think it, we can build it." MEMS technology dates back to the 1970s, but only in the last decade has the technology become more functional, reliable and suitable for low-cost, high-volume production. According to a 1998 study by the European Network of Excellence in Multifunctional Microsystems (NEXUS), the total world market for MEMs is expected to grow from $14 billion to $38 billion by this year. Those figures may seem high until you consider that MEMS applications already are commonly used in read/write heads for computer disks, as inkjet printer heads, to release air bags in automobiles, and in cardiac pacemakers. USF is positioning itself for a piece of the action. In 1997, it landed a $5.5 million Army contract to use MEMS technology to build an environmental sensing device no larger than a pack of cigarettes, capable of analyzing the water and air in potentially hostile environments. That led to a $13.1 million federal contract in 2000 to build a special MEMS test facility scheduled to open this fall in Largo with 20 employees. The 8,000-square-foot facility located in the Pinellas County STAR center is the first in the U.S. to design MEMS for rigorous underwater uses. Chips will be manufactured in contaminant-free "clean rooms" accessible through a small airlock portal where scientists don protective nylon suits, booties and headgear. Inside are stations devoted to AutoCAD design, photolithography (converting designs into pictures that can be overlaid on wafers), and dry and wet processing, in which materials are either added to or etched from the wafer to create tiny parts and machines. The quality of workmanship will be checked with a half-million-dollar super microscope that can magnify an object 800,000 times its actual size. The center's first assignment from the Army is to build a "lab on a chip" with environmental sensing capabilities unheard of just a few years ago. At the same time, center leaders will be promoting MEMS' numerous commercial applications, showing businesses how to use the devices to garner a competitive edge, and possibly working with them to create prototypes for products that can be brought to market. The research and development facility also will serve as a hands-on educational lab for high-school, college and graduate students. And that's just for starters. Businesses may eventually rent equipment in the facility to develop their own MEMS innovations without having to purchase the pricey equipment. Fries hopes all the attention and investment will ultimately result in greater protection for Tampa Bay. "Part of the motivation behind developing technology that's smaller, faster and cheaper is making it easier to do sustained environmental monitoring," says Fries, who can envision a "smart bay" with hundreds of small, unattended sensors transmitting vital diagnostic information. "You can put more nodes out there and collect finer data." And MEMS may turn up on the front lines of the war on invasive species. Compact field units on the drawing boards now, for example, could analyze ballast water from ships entering the bay to detect unwanted aquatic "hitchhikers." For more information on the Center for Ocean Technology or MEMS, contact Carole Steele at 727-553-3975. |
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