It’s an experiment many of us have carried out at home: crashing two Lego creations into each other, bricks flying everywhere. But for the researchers at the General German Automobile Club (ADAC) – which is comparable to AAA in the U.S. – these crashes serve a greater purpose than sheer youthful abandon: testing the reliability of automotive supercomputer simulations.
Reliable car crash simulations are something of a holy grail in automotive safety testing. In theory, they could eventually supplant real-world crash tests, allowing engineers to iterate, test and validate designs much more quickly, with less of a need for costly and time-consuming physical prototyping and real-world impact testing.
So the German computer magazine c’t proposed a lower-stakes test: comparing a supercomputer-powered simulation of two Lego cars colliding with the real thing. After selecting the two models to work with – a Porsche 911 GT3 RS (2,704 pieces) and a Bugatti Chiron (3,599 pieces) – DYNAmore, a German software company, meticulously reconstructed virtual copies of the two Lego models in their software. The software and models were then fed into a supercomputer at the High Performance Computing Center Stuttgart (HLRS).
In parallel, a real crash was prepared at ADAC’s crash test facility in Landsberg, Germany. The two Lego sets were physically built, fitted with grid stripes, and loaded onto the crash rails like any other cars – complete with appropriately sized miniature crash test dummies. The cars even got a crash ID: SI3019PB01, for “Side Impact KW 30 2019 Porsche and Bugatti, first attempt.”
Then, with eight cameras recording at a thousand frames per second and 300 1000-watt halogen spotlights illuminating the scene, the Lego Porsche was hurled at roughly 37 miles per hour into the side of the stationary Bugatti. The Bugatti was halved, hundreds of parts flying through the air, and the passenger compartment of the Porsche was destroyed. ADAC mournfully reported that the “passengers” likely did not survive.
ADAC’s security expert, Andreas Rigling, explained the surprising results. “Simulations in the development process are absolutely important because they save resources,” he said, “but the comparison also shows quite clearly that the real damage is much more extensive than predicted in the simulation. The real crash is therefore indispensable.”
So, for now, supercomputing might not be able to replace the complex, chaotic results of real-world crash tests. Still, it’s easy to anticipate that ADAC will continue to iterate, hoping for the best – after all, this isn’t the first time it’s pulled out all the stops on a Lego crash simulation.