10 Emerging Technologies That Will Change the World

TECHNOLOGY REVIEW

February 2003

Mechatronics

To improve everything from fuel economy to performance, automotive researchers are turning to "mechatronics," the integration of familiar mechanical systems with new electronic components and intelligent-software control. Take brakes. In the next five to 10 years, electromechanical actuators will replace hydraulic cylinders; wires will replace brake fluid lines; and software will mediate between the driver's foot and the action that slows the car. And because lives will depend on such mechatronic systems, Rolf Isermann, an engineer at Darmstadt University of Technology in Darmstadt, Germany, is using software that can identify and correct for flaws in real time to make sure the technology functions impeccably. "There is a German word for it: grndlich ," he says. "It means you do itreally right."

In order to do mechatronic braking right, Isermann's group is developing software that tracks data from three sensors: one detects the flow of electrical current to the brake actuator; a second tracks the actuator's position; and the third measures its clamping force. Isermann's software analyzes those numbers to detect faults-such as an increase in friction-and flashes a dashboard warning light, so the driver can get the car serviced before the fault leads to failure.

"Everybody initially was worried about the safety of electronic devices. I think people are now becoming aware they are safer than mechanical ones," says Karl Hedrick, a mechanical engineer at the University of California, Berkeley. "A large part of the reason they are safer is you can build in fault diagnoses and fault tolerance. Isermann is certainly in the forefront of people developing technology to do this."

Isermann is also working to make engines run cleaner. He is developing software that detects combustion misfires, which can damage catalytic converters and add to pollution. Because it's not practical to have a sensor inside a combustion chamber, Isermann's system relies on data from sensors that measure oxygen levels in exhaust and track the speed of the crankshaft (the mechanism that delivers the engine's force to the wheels). Tiny fluctuations in crankshaft speed accompanied by changes in emissions reveal misfires. If a misfire is detected, the software can warn the driver or, in the future, might automatically fix the problem.

Partnerships with manufacturing companies-including DaimlerChrysler and Continental Teves-merge the basic research from Isermann's group with industry's development of such technologies in actual cars. Isermann says that "80 to 90 percent of the innovations in the development of engines and cars these days are due to electronics and mechatronics." Until recent years, mechatronic systems were found mainly in such big-ticket items as aircraft and industrial equipment or in small precision components for products such as cameras and photocopiers. But new applications in cars and trucks have helped prompt a surge in the number of groups working on mechatronics. The trend has been fueled by falling prices for microprocessors and sensors, more stringent vehicle-emissions regulations in Europe and California, and automakers' wanting to enhance their vehicles with additional comfort and performance features.

Although the luxury market looms largest today-new high-end models from BMW contain more than 70 microprocessors that control more than 120 tiny motors-mechatronics will be moving into the wider car market within five years, says Lino Guzzella, codirector of the Institute of Measurement and Control at the Swiss Federal Institute of Technology. And with software like Isermann's on board, the electronic guts of these new driving machines should be as sturdy and reliable as steel. - David Talbot

Others in 
MECHATRONICS RESEARCHER PROJECT Lino Guzzella 
Swiss Federal Institute of Technology Engine modeling and control systems Karl Hedrick and Masayoshi Tomizuka 
U. California, Berkeley Control systems and theory Uwe Kiencke 
U. Karlsruhe Digital signal processing Philip Koopman 
Carnegie Mellon U. Fault tolerance in control software Lars Nielsen 
Linkping U. Engine control systems