Engineers think big by designing small

Until recently, computers have had to interface with the non-digital world through large and costly sensors and actuators.

Vital research performed at the University of Michigan and elsewhere, however, is rapidly changing this situation. New fabrication technologies have allowed engineers to create affordable, tiny and accurate devices--called MEMS (micro-electromechanical systems)--that provide users, including central computers, with robust information about the world around them. Even better, MEMS will be packaged into wireless integrated microsystems (WIMS), so the resulting devices will be mobile, wearable and even implantable, making computing power truly ubiquitous. Research at the WIMS Center is directed at creating microsystems that gather data locally and process that data locally. The resulting information is then transmitted wirelessly to the user.

The size and mobility of WIMS allow the power of computing to be applied in ways never before possible. Bulky magnetometers useful for detecting military equipment could be shrunk down to the size of confetti and sprinkled from airplanes over the mountains of Afghanistan. Tiny electronic, flying insects could be used to monitor air quality. Implantable neural probes could monitor brain chemistry and administer medication to precisely the right locations. Now that sensors and actuators are matching the size of today's tiniest microprocessors and becoming wirelessly linked to other devices, any object that can benefit from a tiny brain can have one.

What are some current and future possibilities for this emerging and potentially disruptive technology?

Intelligent consumer devices--Chip-based accelerometers and motion sensors have already had a huge impact in automobiles, providing the key mechanism for reliably and affordably sensing when airbags should deploy. Dean Kaman's Segue scooter also uses five MEMS devices to keep itself balanced. The technology is beginning to take off with toy makers and other product designers who use MEMS to create smarter, more agile and more interactive products.

Neural prostheses--Wireless integrated microsystems (WIMS) that provide more accurate measurement and stimulation of brain function could offer new treatments for deafness, epilepsy and Parkinson's disease. The University of Michigan has already been working on a wireless MEMS-based cochlear prosthesis that will vastly improve options for the profoundly deaf. The technology can provide a whole new way for medical devices to improve the quality of life for individuals.

Integrated Environmental Monitors--Environmental scientists currently rely on laboratories full of large and complex equipment to analyze samples brought back from the field. Wireless MEMS technology could shrink these laboratories down to the size of a chip and make them deployable exactly where they are needed. These mini-laboratories could provide instantaneous biohazard warnings or be incorporated into industrial pollution controls. The University of Michigan is developing a low power environmental cube that will contain a variety of sensors, including a microgas analyzer capable of recognizing the top 40 pollutants on the EPA's air toxics list. The device, which will occupy less than two cubic centimeters of space, is designed to detect pollutants with a sensitivity of about one part per billion.

MEMS technology still has a number of significant technical hurdles to overcome, including designing improved power sources and low power controllers for the devices, and developing generic microsystem packages. However, according to MEMS pioneers and ERC-WIMS director Kensall Wise, the technology is ready to take off.

"The technical challenges in MEMS and WIMS technology are clear to us and we continue to make excellent progress," says Wise, who will deliver the keynote address at COMS 2002. "What we need now is for industry to step forward with compelling applications that will drive further development and push the technology downstream to the consumer."

About ERC-WIMS at the University of Michigan
The Engineering Research Center for Wireless Integrated Microsystems (ERC-WIMS) at the University of Michigan is the only National Science Foundation ERC dedicated to WIMS technology in the country. It was established in September 2000 with over $60 million of planned funding. Michigan Engineering has been a leader in MEMS and WIMS technology since pioneering the first on-chip pressure and chemical sensors in 1974. Since then, it has been setting the pace in micromachining, wafer bonding, integration of sensors and circuits, and CAD design of sensors. In 1998, Michigan unveiled a DNA "laboratory on a chip" small enough to fit on a child's finger. ERC-WIMS is currently pursuing innovations in micropower circuits, wireless interfaces, sensors and microinstruments, and micropackaging. For more information, visit www.wimserc.org.

About the College of Engineering
The University of Michigan College of Engineering is consistently ranked among the top engineering schools in the world. The College is composed of 11 academic departments: aerospace engineering; atmospheric, oceanic and space sciences; biomedical engineering; chemical engineering; civil and environmental engineering; electrical engineering and computer science; industrial and operations engineering; materials science and engineering; mechanical engineering; naval architecture and marine engineering; and nuclear engineering and radiological sciences. Each year the College enrolls over 7,000 undergraduate and graduate students and grants about 1,000 undergraduate degrees and 600 masters and doctoral degrees. To learn more, please visit our web site at www.engin.umich.edu.