Jewels of light from a city at night and smoke spewing from factory stacks. People flying in airplanes sometimes see these enduring symbols of the first industrial revolution, which started in the late 18th century and spawned the industrial plants that bring us power, products, and pollution. This revolution replaced our muscle power with mechanized tools of production driven by steam and electrical power. At ORNL we helped this revolution roll along by developing nuclear power plants and other energy sources. We developed control systems to help operate these facilities more efficiently and safely. And we invented instruments to identify, characterize, and measure the concentrations of by-products of these sources—radioactivity and chemical pollutants—to help protect equipment and the health of people and the environment.

It can be argued that the second industrial revolution started in the 1970s with the advent of desktop microcomputers to enhance our brain power by doing clerical and intellectual tasks much more quickly and accurately. Within two decades a large majority of the nation’s professionals had a personal computer (PC) in the office and often one at home. ORNL researchers studied ways to use digital computers to control and analyze reactors and processes. The availability and increasing power of PCs influenced the development of instruments at ORNL and elsewhere because PCs can sort through and compare streams of data and make calculations much more quickly than a human can. As a result, computerized instruments have become faster and more sensitive and accurate than previous instruments.

As suggested by Hal Hellman, editor of Sensors magazine, a third industrial revolution seems to be brewing in the 1990s. As this special issue of the ORNL Review on measurement sciences shows, sensors are being developed at ORNL and elsewhere to extend our senses. Some sensors "hear" sounds that tell us that a submarine is operating too loudly, a machine is malfunctioning, or a person is ill with a specific respiratory disease. Others "sniff out" chemicals to warn of the presence of gases at hazard levels. Still others use lasers and optical fibers to "see" cancerous tumors in parts of the body. Some combine special cameras and software to provide "machine vision" (pattern recognition) to detect flaws in fabrics while being woven and in semiconductor wafers during manufacture. The goals of the research in this area include miniaturization and intelligence—designing smaller, smarter sensors on silicon chips. Such chips will combine sensing with computing, or signal processing, as well as signal transmission to an external receiver. These smart sensors are making possible smart cars, smart homes, smart buildings, and smart machines. They are bringing us closer to a common dream—the Smart Household Robot, who would do our home and yard chores.

ORNL’s traditions in the measurement sciences and its multidisciplinary organization positions us well to develop advanced sensors. We have years of experience developing instruments, beginning with radiation detectors needed to monitor ORNL’s reactors and our employees. Almost half of the R&D 100 awards received in Oak Ridge from R&D magazine have been for developments of measurement, data accquisition and analysis, and control systems. 

We have smart people from many different fields who can work together to devise smart sensors to solve tough problems. For example, because of our multidisciplinary strengths, we offer a variety of approaches to the world’s worst pollution problem—buried land mines that kill and maim people and prevent the use of vast tracts of land. Three of our sensor technologies highlighted in this issue of the Review are being developed to detect the chemical signature of plastic explosives that have leaked out of mines into the soil from which they may vaporize into the air. Our direct-sampling ion trap mass spectrometer, which is being reduced to the size of a briefcase, can be used to sniff out explosive molecules in the soil or air. Our microcantilevers coated with platinum will bend or vibrate in the presence of the explosive RDX because RDX is attracted to platinum, causing a detectable mini-explosion. ORNL researchers have genetically engineered bacteria to light up in the presence of TNT from land mines. 

At ORNL, we have many outside customers because of our expertise in analog and digital chip design and because of our growing expertise in advanced signal processing—extracting meaningful signals from a noisy environment—which is needed for machine vision. Our expertise in algorithm development has aided the development of the government’s systems for automated inspection of stamps and currency to weed out defective items. It has led to software and hardware systems for detecting defects in semiconductor chips and textiles, the heartbeat detector for spotting intruders or escaping prisoners concealed in vehicles, and a device for detecting respiratory disorders using the lung diagnostic system. 

Our customers include nuclear physics groups, functional genomics projects, DOE’s Industries of the Future program (in which DOE helps energy-intensive industries such as aluminum, chemicals, forest products, glass, metalcasting, mining, and steel companies and agriculture rethink how they manage technology), the semiconductor industry, the U.S. military, and agencies needing better surveillance for national security. We are developing detectors to help physicists better understand the universe a few seconds after its birth. We are developing a sensor implant for a mouse to measure its heartbeat rate, pulse rate, blood pressure, and activity in a cage to help determine the physiological and behavioral effects of its defective genes. We are developing a device to image mouse mutations such as skeletal defects, enlarged kidneys, and other abnormally shaped organs, as well as growing tumors and other manifestations of disease. We are helping the U.S. semiconductor and textile industries reduce production of defective items, increase quality, and cut costs. We are working with the military to develop a more rugged and sensitive mass spectrometer system for detecting biological and chemical warfare agents. We have developed instruments for determining that nuclear material is being safely stored and for showing that the Russians have converted weapons material into reactor fuel.

Our nation’s instruments, detectors, and sensors are getting smarter and smaller. And ORNL is playing a big role in these improvements as we help the newest industrial revolution to roll along.