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Institute for Bioengineering, Biotechnology and Quantitative Biomedical Research (QB3)

Tip Sheet: Story Ideas from CITRIS

Tiny, cheap sensors may be the key to making buildings more comfortable and energy efficient, according to Jan Rabaey, UC Berkeley professor of electrical engineering and computer sciences and scientific co-director of the Berkeley Wireless Research Center. With CITRIS funding, he and colleagues in engineering and in the College of Environmental Design's Center for the Built Environment hope to outfit buildings with sensors to measure temperature, air flow, light, sound levels, humidity and more, and connect them in a wireless network that will correlate the information and control air vents, ducts, lights and other machinery.

With such sensors and actuators, a building's environment can be tailored to the users - for example, adjusting temperature by directing airflow based upon occupancy level and time of day, increasing worker comfort. The sensor and actuator network also would save energy by turning off or down unneeded resources.

The key to all this is miniature devices that integrate sensors, wireless communication and a power source - all in a small platform. In about a year's time, prototypes the size of a ping-pong ball will be installed in a couple of campus buildings, but the goal is a device small enough to fit inside furniture, partitions and even ceiling tiles. The devices would be powered by ambient light. An innovative alternative power source is a microvibrator that could sit inside an airduct and generate energy from the vent vibration alone.

- Jan Rabaey, UC Berkeley, (510) 643-8206,

Dr. Thomas Budinger, chair of UC Berkeley's bioengineering department, believes that as many as 60,000 fatal heart attacks could be prevented each year if at-risk people were outfitted with sensors that can detect a cardiac arrest and automatically alert emergency personnel to the person's location and status. That's about 20 percent of the 300,000 people who die of heart attacks every year.

With CITRIS funding, he and his colleagues plan to combine GPS and network communication with pulse-rate sensors on a wrist-worn device. People at moderate to high risk of a heart attack, for whom timely resuscitation is critical, would benefit. Such devices could pave the way for other types of body monitoring devices, including medical monitoring of military personnel.

- Thomas Budinger, UC Berkeley, (510) 642-5833,

To truly reduce the risk of earthquakes, engineers and emergency preparedness agencies need real-time information on the conditions of buildings, bridges and lifeline networks immediately after a quake. CITRIS proposes a way for these structures to monitor themselves - by embedding tens of thousands of inexpensive sensors that also analyze data before sending information about condition and safety to owners and operators.

"One of the goals of CITRIS is to build an infrastructure of high bandwidth, pervasive communications systems so that we can add thousands of cheap sensors to a building and bridges and get a lot of data about its structural health - its performance under normal everyday loads and under earthquake loads," said Gregory Fenves, professor of civil engineering at UC Berkeley. "We're talking about orders of magnitude improvement in the volume and usefulness of information we get."

Fewer than 100 bridges in the state are instrumented now, and the sensors are all very expensive. New technologies, including microelectromechanical systems (MEMS), offer the prospect of cheap sensors with onboard computers and wireless communication with distributed processing of information. CITRIS scientists will develop the technology to place such sensors in buildings and bridges, ultimately making these structures safer, more efficient and more useful.

- Gregory Fenves, UC Berkeley, (510) 643-8543,

Kris Pister, associate professor of electrical engineering and computer sciences at UC Berkeley, is developing a complete sensor/actuator/communication system in a cubic millimeter, a project he has dubbed "smart dust." Such devices will play a big role in CITRIS, with cheap and compact sensors distributed throughout a building to monitor energy use and occupancy, within bridges and buildings to monitor structural integrity, or along freeways to follow traffic flow.

To date, he has shown that various components of this system work independently. For example, he has shown he can communicate via laser between a micro-weather station 21 kilometers away in San Francisco. He and his colleagues also have demonstrated laser beam steering with sub-millimeter mirrors driven by motors all on the same chip, and an eight-inch radio-controlled plane that can fly 60 mph for 18 minutes carrying a video camera with live video feed.

He also has created an integrated device for measuring temperature, humidity, pressure, light, tilt, vibration and magnetic fields with a bi-directional radio link, microprocessor and battery - all in 1 cubic inch, using commercial, off-the-shelf devices. Plus, he has created a tiny operating system that allows these devices to integrate with other systems.

- Kris Pister, UC Berkeley, (510) 643-9268,

One CITRIS project will link roadway sensors throughout the state of California to computers than can analyze traffic flow and tell Caltrans and commuters the state of the freeways. For drivers, this might be an estimate of the time from point A to point B, or the best alternate route. For Caltrans, it might be historical trends, estimates of the best place to make capital investments, or just day-to-day traffic problems. The system also could give planners data to make transit decisions, ranging from the installation of ramp metering to the placement of high occupancy vehicle lanes.

Much of the development work leading to such a system already has been done by a large ongoing program at UC Berkeley called California Partners for Advanced Transit and Highways (PATH). Partially funded by the National Science Foundation, PATH has created all the necessary software and protocols and is hooking up freeway sensors throughout the state. By the end of the year, all should be connected to a central computer and the information available on the Web for Caltrans engineers and planners.

Students also are working on a prototype cellphone that could allow commuters to access traffic information readily.

CITRIS will allow PATH engineers to complete this statewide network and test cheaper MEMS sensors not only on freeways but also on major roads and arterials. PATH researchers also want to perfect a video freeway surveillance system, a prototype of which already is in place in Emeryville, Calif., to enable Caltrans to follow individual cars and, for the first time, determine where the traffic goes.

"Origin-destination studies is the Holy Grail of transportation, because all transportation planning depends upon where people are going, not just how many there are on a particular freeway," said PATH director Pravin Varaiya, professor of electrical engineering and computer sciences at UC Berkeley. "That sort of data is crucial to planning studies, whether it is predicting the impact of a lane closure or of a football game."

- Pravin Varaiya, UC Berkeley, (510) 642-5270,

A small-scale prototype of one type of system envisioned by CITRIS was developed at UC Santa Cruz. The Real-time Environmental Information Network and Analysis System (REINAS) gathers data on the Monterey Bay coastal environment from an extensive network of remote sensors, stores it in a distributed database, and displays data on command via powerful graphics techniques. With REINAS, weather forecasters and environmental scientists can observe, monitor and analyze regional oceanographic and meteorological phenomena in real time from their desktops.

Systems based on the REINAS model have a wide range of potential applications, said Patrick Mantey, dean of UC Santa Cruz's Baskin School of Engineering and director of the REINAS project.

"In this case, it's environmental conditions in Monterey Bay, but it could just as well be traffic patterns or earthquake information," he said.

In addition to UC Santa Cruz researchers, REINAS also involves scientists at the Naval Postgraduate School and the Monterey Bay Aquarium Research Institute.

- Patrick Mantey, UC Santa Cruz, (831) 459-2158,

UC Davis faculty members will conduct two CITRIS projects that should improve understanding of how to maintain good water and air quality as urban areas grow, an issue of critical economic and social value in California.

Debbie Niemeier, professor of civil and environmental engineering, would focus on air quality and vehicle emissions, in coordination with another CITRIS project on transportation systems at UC Berkeley. The air quality effort will include monitoring and analyzing real-time variations in traffic-related pollution at dozens of specific sites in Southern California to better understand the effects of traffic control on travel efficiency and clean air.

Geology professor Jeffrey Mount will lead a project to fully instrument a single ecosystem, such as a small watershed, for long-term environmental studies. This has never been done before in the United States. The instruments would include air samplers and stream-flow gauges.

- Debbie Niemeier, UC Davis, (530) 752-8918,

- Jeffrey Mount, UC Davis, (530) 752-7092,

UC Davis computer science professor Bernd Hamann envisions a future where Bay Area traffic managers stand gazing at 20-foot-by-8-foot "power walls" or interact with stereoscopic visualizations of incoming streams of regional traffic-activity data. The managers wear special glasses and gloves that allow them to adjust traffic patterns through direct manipulation of the visualized data.

This is just one possible area to which the UC Davis Visualization and Graphics Research Group, consisting of faculty members Bernd Hamann, Ken Joy, Kwan-Liu Ma and Nelson Max, can contribute substantially to CITRIS. This UC Davis group will be a partner in developing the technology needed for real-time monitoring and interpretation of massive data streams produced by vast arrays of sensors embedded throughout the Bay Area: sensors in water, soil and air; in major buildings and bridges; and in freeways.

Applications range from the observation and analysis of earthquake phenomena to the development of environmental policies. The research group already is developing visualization software for two "immersive workbenches," where users can view and manipulate three-dimensional data on a large tabletop.

- Bernd Hamann, UC Davis, (530) 754-9157,

UC Davis professor of electrical and computer engineering Ben Yoo wants to link CITRIS projects at various UC campuses via optical networking - high-speed data-transmission systems that use light pulses to carry information. Yoo, director of the Optical Switching & Communications Systems Laboratory, is developing a novel optical router that moves packets of data faster than any existing system. It incorporates new technologies that allow switching on three domains - time, space and wavelength. He is already working on a prototype of this optical router that will link multiple sites on the UC Davis campus through an existing three-mile ring network of optical cable.

- Ben Yoo, UC Davis, (530) 752-7063,


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