The anatomy of the crash

The anatomy of the crash

The technical sensation begins with a very loud bang. At 60 km/h, a device with a shock barrier rams the orange C-Class sedan and hits it square in the side. In this side impact test, the innovation is located in a frame on the hall ceiling above the vehicle: a linear accelerator serves as the X-ray source. Together with the Fraunhofer Institute for High-Speed ​​Dynamics, the Ernst Mach Institute (EMI) in Freiburg, Mercedes-Benz carried out the world's first X-ray crash with a real car. On board were two dummies of the SID IIs model on the left side facing the impact. These are test specimens with female anatomy, specially designed for side impact tests.

Highly dynamic internal deformation processes can be depicted using short-term X-ray technology, as demonstrated by this technology demonstration (proof of concept) in the EMI research crash facility near Freiburg. Previously invisible deformations and their exact processes become transparent. The numerous, high-resolution images allow precise analysis. “By looking into the hidden interior of the Mercedes-Benz X-ray crash, we can help draw important conclusions for further improving vehicle safety,” explains Markus Schäfer, Chief Technology Officer and Member of the Board of Management of Mercedes-Benz Group AG. "Through the successful X-ray crash, we are gaining valuable insights in order to further optimize our technology for recording previously inaccessible information. Fraunhofer EMI is consistently pursuing its strategy of making dynamic processes visible through the use of high-speed X-ray images," adds Malte Kurfiß, head of the crash center at Fraunhofer EMI. "We find out what happens inside a vehicle and with the dummies during an accident. The X-ray images also offer the opportunity to further increase the model quality of the digital prototypes," says Paul Dick, Director of Vehicle Safety at Mercedes-Benz AG.

The vehicle safety department at Mercedes-Benz has been researching the use of X-ray technology in crash tests together with EMI for several years. The decisive factor for the breakthrough was to use a linear accelerator with 1 kHz technology as the radiation source. This means that up to 1,000 images per second are possible – around 1,000 times as many as with conventional X-ray procedures. During the crash test, the beams shine through the body and any dummies from above. An X-ray detector is located under the test vehicle. The X-ray system shoots around 100 still images in the impact time of one tenth of a second. Put together into a video, they provide exciting insights into what happens inside safety-relevant components and in the body of the dummy during the crash. This allows you to observe in great detail how the dummy's thorax is compressed or a component is deformed.