Mercedes-Benz conducted a crash test that goes beyond merely recording what happens to a car in a collision from a few exterior and interior angles, and has recorded through the car’s sheet metal and components with an X-ray machine. The test is the first of its kind, according to the Deutsch automaker, which was able to conduct the X-ray crash test with the help of the Fraunhofer-Institute for High-Speed Dynamics, or Ernst Mach Institute (EMI), in Freiburg, Germany.
The X-ray crash test could help carmakers better understand how impacts affect a vehicle and its passengers. It may seem like an obvious answer to the question of what happens to a car in a major crash. The car (along with anything inside of it) is subject to high impact forces and things are forcibly smashed together. But the test is reportedly teaching Mercedes exactly how things deform during a crash, and is giving the carmaker insight into precisely how a crash dummy is pressed into or against the cabin walls of a vehicle. Per Mercedes-Benz:
At 60 km/h, a device with a crash barrier rams into the orange C-Class saloon and hits it full on the side. Crash tests are always something special – even for the experts. But the really spectacular part of this side impact test is located in a frame on the hall ceiling above the vehicle: A linear accelerator serves as an X-ray camera. Together with the Fraunhofer-Institute for High-Speed Dynamics, the EMI (Ernst Mach Institute) in Freiburg, Mercedes-Benz has now carried out the world’s first X-ray crash with a real car. On board was one SID II dummy on the left-hand side facing the impact. This is a test specimen with a female anatomy, specially designed for side impact tests.
This technology demonstration (proof of concept) at the EMI research crash facility in Freiburg has shown that high-speed X-ray technology can be used to visualise highly dynamic internal deformation processes. Previously invisible deformations and their exact processes thus become transparent. The numerous, high-resolution images allow precise analysis.
In order to literally see through the crash, Mercedes-Benz took an S-Class and carried out a side impact test at roughly 37 miles per hour with a crash dummy in the driver’s seat, which is more or less standard fare in the world of collision testing. A linear accelerator, however, was suspended over the car, and functioned as an X-ray camera, much like one used at the airport or by a doctor.
The dummy used was notably a female version, which Mercedes claims is designed for its specific tests. It’s worth mentioning that women are at greater risk of serious injury in collisions because crash tests are not usually conducted with them in mind.
Studies have shown that crash tests produce more accurate results for men, which means that safety is lagging for women. It’s noteworthy that Mercedes-Benz is taking this blind spot into account and conducting more thorough tests, such as this latest X-ray experiment.
The camera, or linear accelerator, sits above the stationary S-Class and shoots radiation in the form of X-ray pulses at the car, which rests above a flat detector located under the vehicle that acts as a “digital image receiver.” When the X-ray pulses hit the detector, an electrical signal is generated. Its intensity depends on how strongly radiation is absorbed by the solid objects in the test, namely the car and crash dummy, as the carmaker explains. The signal “influences the grey value that is later visible,” per M-B, and the final result looks like this:
As Mercedes-Benz points out, this latest crash test performed by the carmaker and EMI may be “the world’s first X-ray crash with a real car.” But the EMI has long been interested in X-raying vehicle collisions, as well as how components inside cars, like air bags, look through the lens of electromagnetic radiation.
The institute has previously X-rayed a running motorcycle engine, and the lead-up to this Mercedes experiment was a crash test of a Lego Technic Porsche 911 GT 3RS, which the scientists crashed into a wall at almost 19 MPH. It’s likely that the test confirmed what we’ve always suspected: Legos are indestructible, which is partially why it hurts so damn much to step on one.
