Autonomous Emergency Braking

Humans are still a factor in the adaptation of automatic braking

3 min read
Autonomous Emergency Braking
Illustration: McKible

DriverlessCarsMasterBraking Illustration: mckibillo

The remarkable thing about letting a car do the braking for you is not that the car stops. It’s how late the car hits the brakes. It’s almost as if a teenager were testing his or her reflexes. Those of us raised on automatic transmissions and cruise control may expect cars to take flighty human drivers out of the loop rather quickly. But if my ride in a test vehicle at the 2013 Frankfurt Motor Show is any indicator, carmakers are taking their time taking over. Even the most imperturbable driving instructor might get jumpy using today’s autonomous emergency braking (AEB), also called advanced emergency braking systems.

AEB isn’t even a teenager: Mercedes-Benz introduced an early version with its 2005 S-Class. That system used radar to detect obstacles, warned drivers, and primed brakes so that they would be more effective when the driver finally used them. Yet in an indoor test in simulated foggy conditions, the car’s radar failed to activate the system. A journalist crashed one into another Mercedes-Benz during a televised demonstration. Company engineers later decided that the garage’s steel interior had confused the radar. But the technology is maturing, and the European New Car Assessment Programme (Euro NCAP), a public-private car-testing body and the counterpart to the U.S. NCAP, will require AEB to obtain its highest safety rating next year

Now the state of the art is to use more than one type of sensor to cross-check for obstacles, carmakers say. Some complement radar systems with optical cameras. Today’s S-Class has short-range and long-range radar, optical cameras, and ultrasonic detectors for the closest obstacles. Optical cameras can be fooled by sunlight, wet roads, and night, of course, and ultrasonic sensors work only at the shortest ranges and lowest speeds. Certain research vehicles also include lidar, a radarlike system that uses light rather than radio waves. As the instruments grow smaller and cheaper, carmakers may include lidar in production cars as well.

Yet carmakers still hesitate to override a driver’s instincts. The German auto club ADAC reported in a test [pdf] that it deducted points from a BMW 5 Series for initiating only partial braking after warning the driver. But such a limited action may please self-confident drivers. Harald Barth, a product marketing manager at car supplier Valeo, says that one reason carmakers have kept the brakes on autonomous driving is that they want to win the trust of drivers. “We need not just to offer good systems but also to educate the end user. We are going step by step,” he says.

That will also give engineers more time to figure out how humans react to having control taken away from them. Last year, a pair of studies applied analyses called system-of-systems and operator sequence diagrams to AEB scenarios. They both found that when autonomous systems attempt to take over from human drivers, humans do not always respond well. Or sometimes drivers respond too well and do not react in time to take over again when the autonomous systems attempt to return control to them. The latter study sounded a grim note: “There are no formal methods for testing the performance of AEBs from either a technical or human factors point of view. The effectiveness of AEBs will, however, become increasingly clear in the coming years through fatality and injury statistics,” its authors wrote.

Going slow will also give Euro NCAP and other testing bodies more time to improve their testing capacity. Now Euro NCAP uses a small trailer as the crash target, allowing only simulated rear-end collisions, but it says it will develop targets simulating pedestrians, among other improvements [pdf]. For pedestrians, if not anxious driving instructors, that should be a relief.

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Becoming a Leader at NASA

Marcellus Proctor oversees major space projects

2 min read
Marcellus Proctor

"Growing up in the Bowie, Md., area, whenever we drove by NASA's Goddard Space Flight Center, I told my parents that I would work there someday," recounts Proctor, who is now an associate chief at Goddard for NASA's Electrical Engineering Division (EED).

Originally, Proctor was focused on astronomy, but during high school at an engineering exploration summer program he solved "a resistor equivalence problem that nobody else in the class had gotten [and] the instructor recommended I look at electrical engineering as a career instead." He got a master's in EE from Johns Hopkins University. "I started working at Tracor Systems (now part of BAE Systems) in their Standard Missile Program," recalls Proctor. "In 2001, after three years there, an opening at Goddard became available. I applied...and I've been there ever since."

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Virtual IEEE-USA Conference Focuses on Tips for How to Enhance Your Career

Register now for the free 3 November event

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Registration is now open for EVO 2.0, IEEE-USA's third and final virtual event of the year, taking place on 3 November. The free half-day conference features all-new speakers, with a continued focus on emerging technology, future perspectives, and career-enhancing tips.

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EP29LPSP: Applications in Plasma Physics, Astronomy, and Highway Engineering

Ideal for demanding cryogenic environments, two-part EP29LPSP can withstand temperatures as low as 4K

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Since its introduction in 1978, Master Bond EP29LPSP has been the epoxy compound of choice in a variety of challenging applications. Ideal for demanding cryogenic environments, two-part EP29LPSP can withstand temperatures as low as 4K and can resist cryogenic shock when, for instance, it is cooled from room temperature to cryogenic temperatures within a 5-10 minute window. Optically clear EP29LPSP has superior physical strength, electrical insulation, and chemical resistance properties. It also meets NASA low outgassing requirements and exhibits a low exotherm during cure. This low viscosity compound is easy to apply and bonds well to metals, glass, ceramics, and many different plastics. Curable at room temperature, EP29LPSP attains its best results when cured at 130-165°F for 6-8 hours.

In over a dozen published research articles, patents, and manufacturers' specifications, scientists and engineers have identified EP29LPSP for use in their applications due to its unparalleled performance in one or more areas. Table 1 highlights several commercial and research applications that use Master Bond EP29LPSP. Table 2 summarizes several patents that reference EP29LPSP. Following each table are brief descriptions of the role Master Bond EP29LPSP plays in each application or invention.

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