Sunday, June 21, 2009 Post a Comment
Wisconsin: Crash laboratory teaches more than driving safety
One purpose is to aid the design of better technologies to protect auto occupants.
BY DAVID STEINKRAUS THE ASSOCIATED PRESS
http://www.thonline.com/article.cfm?id=247458
MILWAUKEE -- If ever there was a place to convince you of the need for careful driving it is this one, tucked into a pair of nondescript buildings in an obscure corner on the grounds of the Clement J. Zablocki VA Medical Center.
The crumpled cars are a clue even before you step inside the long, high shed where 471 feet of concrete track ends in a collision chamber lined with concrete blocks to contain the energy of colliding vehicles. With the summer driving season's unofficial kickoff this weekend, with the likelihood of more people driving to nearby vacations in this economically troubled year, it's worth looking for lessons amid the pieces of glass and metal in the automobile crash laboratory run by the Medical College of Wisconsin.
There is a dual purpose for the regular bashing of Audis, Toyotas, Fords, Jaguars and others, said Narayan Yoganandan of the medical college, and both purposes are rooted in trying to understand how injuries occur in a motor vehicle crash. One purpose is to aid the design of better technologies to protect auto occupants. The other is to generate knowledge that will help physicians provide better treatment. Yoganandan, who holds a Ph.D. in biomedical engineering, is chairman of biomedical engineering in the Neurosurgery Department at the medical college.
The crash lab has been running tests in this spot for about 20 years and is one of the contractors used by the federal government to test vehicles for their response in side impacts. (There's another testing contractor in Wisconsin, too: MGA Research Corp. of Burlington.)
Side impact crashes are done at 39 mph as cars are hit by a wheeled sled weighing 3,000 pounds with a front that replicates a car bumper. Front-impact tests are done at 35 mph.
The result is the government's crash ratings in which the occupants of a 5-star vehicle would suffer serious injuries in 10 or fewer of every 100 crashes. In cars rating 1 star, occupants would have serious injuries in 46 or more of every 100 crashes. (You can look results up by model year and make at http://www.safercar.gov)
The newest part of the lab is next door in the neurosurgery research facility.
Here a metal platform is shoved down a track by an air-powered ram, and on the platform is a test dummy.
The platform can carry more sensors, and cameras can be mounted all around the room to photograph what happens to the dummy from various angles, and it's easier to measure all the forces by taking dummies out of cars.
More importantly, from the standpoint of science, is the ability to repeat an event. Unlike a car crash, a computer controls the platform, and can change the forces applied in minute ways, and can do that again and again.
Michael Schlick, a research engineer and the lab manager, flipped open a notebook and showed a graph plotting the forces recorded in a crash. Instead of being a smooth line covering a few tenths of a second, the plot had little steps in it. Those minute changes in force may come from a bumper crumpling or an engine mount absorbing energy and then failing, he said.
"There's two cars, identical cars, you'll never get the same result," Yoganandan said. "Whereas here, if you set up everything perfect, you can get absolute repeatability."
At the moment the lab is studying crash dummies as part of a national project to design a better one. Schlick illustrated the need by bending the neck of a standard crash dummy. It's stiff, which means that in a frontal impact, the dummy's head snaps down and the forehead hits the steering wheel. In reality, he said, the human head moves forward slightly first in a crash, as if you were pushing your face forward. In reality that means that people's chins, teeth and noses hit the steering wheel.
Yoganandan said we have made great progress in auto safety. When the government began issuing crash worthiness ratings, most cars earned only 1 or 2 stars. "And now what has happened is there are very few cars at 1."
But we're also learning that modern technologies, the ages of occupants, how their weight is distributed, and other factors affect injuries, he said.
Last month, a group of medical college researchers published a study saying that newer vehicles, because of their better protection, have decreased the likelihood of facial fractures, the most common injury in motor vehicle collisions. But at the same time, the study said, the frequency of injuries hasn't dropped in side-impact collisions, suggesting that there is work to be done.
We may have reached a plateau in crash safety. Nationally crashes have killed about 43,000 people annually for several years, said Jacob Nelson, national director of traffic safety policy for AAA.
Information from the state Transportation Department shows the number of crashes and fatal crashes in Wisconsin was relatively steady from 2002 to 2007, and the number of crashes per 100 people varies little from year to year and county to county. For Racine County, that has meant about two crashes per 100 people.
"There's no way to know exactly why that is, but there definitely is a culture of complacency about the toll that you pay for travel on America's roadways," Nelson said.
"A lot of what causes crashes is basically preventable. They're decisions people make. People make a decision to speed." Or they decide not to wear seat belts, or to drive drunk. Those are the three largest factors in traffic crashes.
"So I think we really need to start looking at driver behavior and how we can change driver behavior in a positive way."
AAA is starting on just such a project, he said.
In other words, the road to safer highways is still long, and we still have far to go.
Given that young drivers account for a disproportionally high level of accidents on Britain's roads, a majority of motorists would likely give their support to push the age at which people can legally get behind the wheel up to 18, or even 21.