Story highlights The engineers at Humanetics, which manufactures crash-test dummies, teamed up with a University of Michigan doctor

They made two new crash-test dummies to reflect an aging and obese population

(CNN) Crash-test dummies need to look like real people to measure injuries in auto accidents -- and for Americans these days, that means looking older and fatter.

Engineers at Humanetics, a company that manufactures crash-test dummies, teamed up with University of Michigan trauma surgeon Stewart Wang to create new dummies that have put on some pounds and carry the effects of advancing years.

Humanetics crafted two new dummies: an obese dummy that weighs 273 pounds, and a dummy that is based on an overweight 70-year-old woman. The obese dummy is more than 100 pounds heavier than a normal crash-test dummy.

"The typical patient today is overweight or obese -- they're the rule rather than the exception. You can't talk about injuries without talking about the person," Wang, director of the University of Michigan International Center for Automotive Medicine (ICAM), said in a statement. The ICAM team helped create the new dummies by choosing 6,000 computerized scans from a national database to provide appropriate averages to the Humanetics team, and the data was used in 3-D printing of the dummy prototypes.

Dr. Stewart Wang demonstrates how to secure an "elderly" crash-test dummy.

"The population is getting older, and as it gets older it gets fatter as well," Wang said. That's why ICAM gathered data from the largest population ever, according to Wang.

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