More crashworthy cars with opitimization

Optimization is an effective method for enhancing the crashworthiness of cars. In a series of simulations of crash tests at Linköping University in Sweden it was possible to reduce the penetration of passenger space by a third.

Every year 47,000 people are killed in automobile accidents in the EU. This is as if a jumbo jet were to crash every third day. Such horrendous figures cry out for ever greater investments in crashworthiness. Modern optimization technique, based on so-called finite element methods, can bring us safer cars at a considerably lower cost of development.

A study carried out at the Linköping University Division of Solid Mechanics in collaboration with SAAB Automobile AB shows that it is possible to cut calculation times to one fourth of the time using traditional optimization methods. In his doctoral dissertation, Marcus Redhe describes 26 assessments that he carried out on a collision model of a SAAB 9-3. The optimization technique he used is called Space Mapping. The basis for calculations was a crash test of an American model in which the car was driven straight into a steel barrier at 56 km/h.

By varying the thickness of the sheet metal in seven of the car’s crash-absorption components, the penetration of the passenger space by material was reduced by 32 percent.

“Effective optimization methods are an important tool for the auto industry. The challenge is to continuously enhance the safety of cars while cutting the time spent on development. To optimize construction in the traditional way, in which each alternative is tested separately, is too slow and doesn’t always produce the best results,” says Tomas Sjödin, director of crash simulations at SAAB Automobile.