In cars, the crumple zone is meant to be crushed and compacted in order to absorb some of the energy of the collision, protecting the passenger cabin in the process. DLR's new rail car crumple zone works in a similar way, using a series of metal cylinders that slide into slots to create a "controlled deformation process" that saps the kinetic energy out of a crash.

To test their prototype, DLR's engineers attached it to the front of an 80-ton tanker car loaded with cameras and sensors and then slammed a second tanker car into it at a (somewhat sluggish) 11.5 mph. The result? The unprotected tanker was mostly undamaged and the prototype with the crumple zone budged a bit. Naturally, DLR brought along a video showing the device in action (audio in German):