Why have crash test dummies survived?

Countless lives have been saved by crash test dummies, which have been around in their current form for some 15 years

Even in our digital age, crash test dummies made of metal and plastic are as important for carmakers as they were when they first appeared in the 1960s. And not only that, they are getting smarter too.

Computer animations are no match for the human-sized, high-tech dolls, which do not bat an eyelid when they are hurled with unrelenting force at brick walls, metal poles and other vehicles.

The dummies consist of a robust metal spine clad with a mixture of foam rubber, vinyl and plastic foam, which is designed to simulate the vulnerable human form.

Sensors measure crash data, transmitting the physical forces acting on the dummy within milliseconds. Engineers analyse the data streams from the accelerometers and high-speed cameras installed.

The way the doll reacts to rapid deceleration and impacts gives researchers a unique insight into how flesh and bones react in a real-life crash. The information is used to run computer programmes which provide even more details. “We use dummies for all tests related to occupant safety,” said Hermann Steffan of the Vehicle Safety Institute at Graz Technical University in Austria.

What about simulation?

What keeps the crash test dummies in work is the enormous calculating power required to stage car crash simulations. “The interrelationships of how a vehicle and its occupants behave in a crash scenario are enormously complex in data terms,” said Wolfgang Sigloch of the Dekra vehicle testing agency of Germany.

The twisting radius of the doll’s neck and the deformability of the chest region make dummies ideal for ultra-realistic testing. At the moment there is no alternative, say safety experts.

The dummies are multi-jointed forms whose behaviour in crash situations cannot be predicted with 100-per-cent mathematical accuracy. We need them to check to see if our figures are correct.

Crash test dummies need to be tough but sensitive. “The most important attributes are robustness coupled with extreme sensitivity,” said Wolfgang Sigloch. The dummies must survive repeated impacts without falling apart.

Damaged components can be replaced and when they become too battle-scared, dummies are retired from service. Some even find their way into museums.

Not all dummies are the same and there are special models for crash tests involving side and rear collisions. The most widely used dummy is the Hybrid III which is a standard issue for evaluating automotive safety restraint systems in frontal crash testing throughout North America and Europe.

Hybrid III was originally developed by General Motors and the most modern versions feature a segmented rubber and aluminium neck along with curved cylindrical rubber lumbar spine mounts. The latter reproduce the typical, human-like slouch of a seated person.