Radiation from space floated as possible cause of Toyota issues


— It may sound far-fetched, but federal regulators are studying whether
sudden acceleration in Toyotas is linked to cosmic rays.

Radiation from space long has affected airplanes and
spacecraft, and is known for triggering errors in computer systems, but
has received scant attention in the auto industry.

The questions show how deep regulators and automakers may have to dig to solve the mysteries of sudden acceleration. Toyota
says it is fixing mechanical problems — floor mats and sticky pedals —
that explain sudden acceleration in 13 models and 5.6 million vehicles.

But at least half of more than 1,500 recent complaints to regulators involve other models, raising questions whether Toyota has fixed its problem.

An anonymous tipster whose complaint prompted regulators to look at the issue said the design of Toyota’s microprocessors, memory chips and software could make them more vulnerable than those of other automakers.

“I think it could be a real issue with Toyota,” Sung Chung, who runs a California testing firm, said.

Toyota, which has led the auto industry in using electronic controls, told the Detroit Free Press its engine controls are “robust against this type of interference.”

Electronics makers have known for decades about
“single event upsets,” computer errors from radiation created when
cosmic rays strike the atmosphere.

With more than 3,000 complaints to U.S. regulators of random sudden acceleration problems in Toyota models, several researchers say single event upsets deserve a close look.

The phenomenon can trigger software crashes that
come and go without a trace. Unlike interference from radio waves,
there’s no way to physically block particles; such errors typically
have to be prevented by a combination of software and hardware design.

And an anonymous tipster told NHTSA last month that “the automotive industry has yet to truly anticipate SEUs.”

Such radiation “occurs virtually anywhere,” said William Price, who spent 20 years at the Jet Propulsion Lab
testing for radiation effects on electronics. “It doesn’t happen in a
certain locale, like you would expect in an electromagnetic problem
from a radio tower or something else.”

Toyota staunchly defends its electronics, saying they were designed for “absolute reliability.” Responding to the Detroit Free Press, Toyota
said its systems “are not the same as typical consumer electronics. The
durability, size, susceptibility and specifications of the automotive
electronics make them robust against this type of interference.”

Testing for the problem would involve putting
vehicles in front of a particle accelerator and showering them with
radiation, a step that experts said would help resolve the question.

“Nobody wants to come out and say, ‘We have issues, and we need to test,’ ” said Chung, president of the testing firm Eigenix.

The phenomenon was first noted in the 1950s to
affect electronics at high altitudes; unlike electromagnetic waves,
there are no ways to physically shield circuits from such particles.
Airplane and spacecraft makers have long designed their electronics
with such radiation in mind, through safeguards such as systems that
triple-check data.

Only in the late 1970s did researchers discover that
a minuscule portion of such radiation falls to earth. It’s not enough
to harm humans, but as circuits in computers and cell phones on the
ground have shrunk to the width of several dozen atoms, the risk of
errors has grown. “Five years ago, it was a problem in very few
applications,” said Olivier Lauzeral, general manager of IRoC
Technologies, which tests chips and software for SEU resistance. “In
the past couple of years, we’ve seen a rise in demand and interest.”

In an anonymous e-mail last month to the National Highway Traffic Safety Administration,
a tipster said such an error “may be one reasonable explanation for
incidents of sudden acceleration,” adding that the automotive industry
had yet to adapt the techniques used by aircraft firms to prevent
problems from SEUs.

NHTSA added the tipster’s information to its electronic investigative file on Toyota recalls. The agency declined several requests from the Detroit Free Press for comment.

Electronic throttle controls like the ones under
scrutiny in Toyotas are widespread in the industry. They’re more
reliable than mechanical links; they save weight and space; and they
make other technology, like stability control, possible.


(c) 2010, Detroit Free Press.

Visit the Freep, the World Wide Web site of the Detroit Free Press, at http://www.freep.com.

Distributed by McClatchy-Tribune Information Services.


Please enter your comment!
Please enter your name here