Crashtest

A crash test [ kræʃ - ] is an attempt at a collision of vehicles under realistic but controlled conditions. Such tests are particularly common in the automotive industry in the development of vehicles and safety systems. They are generally used to gain insights into the behavior of a vehicle, its occupants or cargo at different crash configurations. The result is either the confirmation of the desired vehicle security, detection of vulnerabilities that need to be eliminated.

Of detecting the presence of a quality assurance system on the part of the manufacturer is now mandatory for national type approval of vehicles in Germany, especially for General Type Approval (ABG ). The associated implementation of quality assurance includes indirectly the performance of crash tests by the manufacturer. As vehicle manufacturers are generally seeks to open up larger markets for their vehicles, usually occurs on the local statutory provisions a number of other provisions added, such as the recommendations of the United Nations Economic Commission for Europe (UNECE), Transport Division, which reflected in EU directives (see ECE R), and other institutions. In the U.S., there are other type of licenses and a separate set of rules for vehicle safety (see FMVSS and others) before, which is different from other parts of the world (especially Europe) is different, so local manufacturers usually have their models in the U.S. to complete separate crash tests, if they intend to market them there.

Basic

In a crash test, a vehicle is driven under defined conditions against a fixed rigid or deformable obstacle, further, there is the opportunity to drive the vehicle -to-vehicle crashes or simulate collisions with pedestrians. The effects are recorded by numerous sensors and recording with high-speed cameras.

The crash test is usually held in a special test facility. The vehicle is accelerated by a towing cable to the speed necessary depending on the test and impinges on the end of the route to the obstruction. In so-called sled tests (the most common type of crash tests conducted ), only the body shell is mounted on a slide with the components to be tested and at the end of the route defined delayed by a corresponding device. The carriage and the body are not destroyed in the crash. Crash test with the whole vehicle are already being implemented in the prototype phase. They are used primarily to hedge structure of the vehicle. For side impact tests and the other standing obstacle can (eg Deformable Barrier ) are mounted on a rollable car and accelerated toward the stationary vehicle.

With the help of tracking systems such as the CCV system crash tests can also be performed outside of solid experimental facilities at any location. Such systems are, for example, by DEKRA, and have been used by DaimlerChrysler. The vehicles are driven by its own engine. Possible test modes are eg block impact (eg Euro NCAP, U.S. NCAP, FMVSS ), impact with an obstacle (eg tree), guardrail collision, vehicle -to-vehicle crash.

Depending on the experimental setup can be as a variety of crash situations can be achieved (eg collision with a tree, collision with another vehicle head-on, side or from behind with a different cover ). Outside standardized crash configurations and real traffic accidents are simulated. Here, the data of an accident or of expert or witness statements serve as the basis for the configuration. Such attempts are often given for forensic expert opinion in order to recreate an accident situation. A crash test almost always leads to the destruction of the investigated vehicle - often with expensive prototypes. If it is possible, these tests should therefore be replaced by the computer simulations ( see finite element method). Sometimes no complete vehicles are used, but only the relevant sections.

For the simulation of vehicle occupants so-called dummies are used.

Systematic implementation of crash test series

Euro NCAP to 2008

A common European manufacturer-independent crash test program is Euro NCAP. The acronym stands for " European New Car Assessment Program" and existed until the end of 2008 following three parts:

• Occupant protection Frontal Crash: The vehicle is accelerated to a speed of 64 km / h and then bounces offset laterally, frontally into a deformable barrier.
• Side crash A 50 km / h barrier, which is mounted on a carriage abuts laterally together with the vehicle.
• Pole crash: At 30 km / h vehicle crashes laterally at the height of the driver on a steel column.

• Various tests to evaluate the safety of children that are fixed in a Isofix system or special pillow with a belt in accident situations.

• Crash with a pedestrian: Here, several individual tests are performed with a dummy and at a speed of 40 km / hr.

Euro NCAP in 2009

Since 2009, the Euro NCAP has been extended; Since then he covers the four areas

• Occupant protection Frontal Crash: The vehicle is accelerated to a speed of 64 km / h and then bounces offset laterally, frontally into a deformable barrier.
• Side crash A 50 km / h barrier, which is mounted on a carriage abuts laterally together with the vehicle.
• Pole crash: At 30 km / h vehicle crashes laterally at the height of the driver on a steel column.
• Rear crash: study the safety of headrests, restraint systems and airbags on all seats in the protection of the cervical spine

• Various tests to evaluate the safety of children that are fixed in a Isofix system or special pillow with a belt in accident situations.

• Crash with a pedestrian: Here, several individual tests are performed with a dummy and at a speed of 40 km / hr.

• Assessment of the presence and the effectiveness of the safety systems, seat belt reminders, ESP systems and speed limiters.