The Center for Embedded Networked Sensing (CENS), a UCLA-based consortium of six schools, is testing and perfecting wireless sensing technology to connect major chunks of the physical world to the internet–and the technology also is being used to give students a glimpse of science in the real world.

CENS currently supports graduate student research, offers a summer undergraduate internship, and has a program for high school students. This summer, 11 high school students and 14 undergraduates are interning with the consortium.

Once the stuff of science fiction, wireless sensor networking is quickly catching on, attracting the attention of academics, the military, and corporations. Just as the internet virtually connected people with personal computers, the prospect of millions of tiny wireless sensors and cameras sprinkled in buildings, farmland, forests, and hospitals promises to create unprecedented links between people and physical locations.

Such networks could monitor the environment for pollutants, gauge whether structures are at risk of collapse, or remotely follow medical patients in real time.

“I see this as the next wave of extending the internet into the physical world,” said computer scientist Deborah Estrin, who heads CENS.

Researchers at the consortium already have scattered wireless networks of nodes in the rice paddies of Bangladesh, rain forests of Costa Rica, and wilderness of California’s San Jacinto Mountains–all for the sake of keeping a closer eye on the world.

The technology also has implications for education, as students are able to work alongside scientists, collecting and interpreting real data.

“I think there’s a tremendous potential for bringing wireless sensor applications into schools, because this area of research is highly connected to social applications,” said Karen Kim, CENS’ education director. “Research shows that [often] kids find science and engineering more interesting when they can see how it connects to their real life.”

Said Kim: “These are not just canned projects for students; they are doing the actual project. That’s one major way the sensors can be used in education–by bringing students into a lab and having them work hands-on with people who are doing the research.”

Ed-tech advocates echo Kim’s statement that when students can see and experience real-world applications for the math and science topics they study in school, they are more likely to retain and develop their interest in these fields.

The CENS lab works with middle-school students in developing inquiry-based activities in which students connect to the wireless sensor networks through an online application. These activities are linked to current research projects. One example, Kim said, is a “plant module,” linked to California state standards, that teaches seventh graders about evolution, adaptation, scientific inquiry, and photosynthesis.

Using sensors in mountainous areas, students tap into the network to access data and answer questions pertaining to the growth of leaves and trees.

CENS is working on a partnership with the Los Angeles Unified School District to develop a science-focused learning community and explore how to integrate different CENS projects into the curriculum, Kim said.

Wireless sensors also are helping students learn about water contamination in the Los Angeles River. The Urban Sensing project, a collaboration between CENS and the Center for Research in Engineering, Media, and Performance, involves developing and deploying sensors in the river.

“We’re imaging a case where we have a wireless sensor network in the river, looking at contamination and water quality, and students do activities on the network to access the data,” Kim said.

Along the same lines, a UCLA professor conducts a service-learning course in which undergraduates travel to sixth-grade classes and teach the students about water quality. The classes use water sensors at local beaches to identify specific bacteria in the water.

“In L.A., there are lots of beach closures, so this is a real-life experience that the kids will understand,” Kim said.

The wireless sensors offer numerous opportunities for students to tap into research projects and work with scientists, but the sensors also raise some privacy and security concerns.

Advances in miniaturization and integration of hardware have enabled the design of smart sensor nodes ranging from a square inch to the size of a matchbox.

However, the rush to cram tiny cameras into the nooks and crannies of daily life raises concerns among some observers who fear rogues could hack into the networks. Corporations are beefing up safeguards, and academics are studying privacy pitfalls and trying to build stronger networks to protect against security breaches.

The commercial possibilities have spawned a cottage industry of startups intent on developing cheap, reliable wireless nodes. Several of these ventures, including Dust Networks and Arch Rock Corp., have connections to the University of California, Berkeley, which was involved in early efforts to develop “smart dust,” or sensors the size of dust that could be sprinkled in hard-to-reach places.

Today, the technology is primarily used to monitor pipelines and control climate conditions inside factories. Demand for more uses in the home, agriculture, and health care could push the market from several hundred million dollars currently to $8 billion worldwide by 2010, according to San Diego-based wireless market research firm ON World.

That growth has been slowed by compatibility issues, with many sensors now custom-made for specific tasks. The ZigBee Alliance, composed of more than 150 companies, is developing rules to make networks interoperable, but a universal standard is still years away.

Wireless nodes, or motes, are made up of microprocessors, sensors, and low-frequency radio transceivers to communicate to the outside world. The capability of the sensors varies and can measure temperature, light, stress, or other conditions.

Motes are usually densely packed in an environment–like a vineyard or waterway–to monitor the surroundings. Most are battery-powered, while smaller versions are solar-powered. The cost ranges from $20 to several hundred dollars, depending on the type of sensors.

As with any wireless technology, sensor networks can be prone to malicious security attacks or illegal eavesdropping, said Adrian Perrig, an assistant professor of electrical and computer engineering at Carnegie Mellon University. He has written extensively about security and privacy hurdles of wireless sensor communication and is working to create more secure networks.

“If poorly secured networks are deployed and exploited, people may have significant concerns about sensor technology,” he said.

Research at the main CENS building, which opened last year, is funded by the National Science Foundation, which committed $40 million over 10 years for the center. The building serves as a central hub for scientists in various fields of wireless sensor networking to work under one roof.

A sign posted in the lobby makes it clear the space is not private: “Research in progress. Electronic sensing and monitoring devices in use within this space, including cameras and microphones.”

“These are not toy systems,” said John Cozzens, a program director at the foundation. Researchers labor behind white cubicles analyzing data spit back by wireless sensors nestled in the physical world.

One of the fields where researchers believe wireless sensor technology could be commonplace is in the health-care setting.

Graduate student Sasank Reddy is working on a project to determine if it’s better to measure caloric intake by toting around a cell-phone camera and taking pictures at mealtime or self-reporting eating habits on a standard dietary questionnaire.

He recently hung a primitive mote around his neck–actually, a camera phone–as he lunched. The camera snapped away every 10 seconds as he nibbled on his Italian sub.

Later, as he browsed through the images on his work computer, Reddy saw some red flags and determined the technique wasn’t ready for prime-time: Some pictures came out too blurry. Others showed the faces of fellow diners in the background, raising privacy issues.

“I get a ton of information about what I’m eating, but there are data that shouldn’t be shared,” he said.


Center for Embedded Network Sensing

ZigBee Alliance