Crash tests are today a standard activity of carmakers. Thousands of cars, many in prototype form, are propelled into solid barriers or hit at the sides and rear as well as rolled over. The results of such crashes are fully documented using high-speed cameras and engineers study what happens to the bodywork as well as the highly sophisticated dummies which represent human occupants.
But such sophistication was not found in crash tests in the 1950s when Renault conducted the first ‘destructive tests’ on its products. In 1955, Renault engineers tested the resistance of the Dauphine model in front impact, side impact and rollover accident situations. Five years later, a detailed analysis of deformations on some 100 Dauphines that had been involved in collisions was one of the first-ever accident research studies in Europe.
In those early years, no on-board measurements could be made during the tests and the dummies used at the time were made with wire and fabric-covered straw to simulate various parts of the human body. But they were not entirely as simple as store mannequins as the head was more sophisticated – it could break open at a certain degree of impact against a rigid element. It consisted of a plastic shell filled with lead and fat, to make up the mass of approximately 5 kg, similar to that of a human head. In testing, it was designed to shatter if dropped from a height of 1 metre onto a hard surface, which corresponded to the result of biomechanical tests carried out on real skulls.
While the first crash tests focussed on the effects of a car being rammed into a solid non-moving obstacle, more ‘real-world’ situations were progressively added by Renault researchers. As Renault made many small cars, the effects of a small car colliding with a larger one were of great interest as it was necessary to provide the occupants of the smaller car with as much protection as possible.
One of the earliest studies in this respect was conducted using a Renault 5 which was put into a head-on collision with a Zephyr in 1972. Initially, it was apparent that the small car suffered severe damage which would have certainly caused serious injuries to the occupants. But before long, solutions were found and Renault demonstrated how it was possible to improve the situation. Basic changes in structural design were necessary to make the small car stiffer and the large car more flexible. The result was eloquent: the small car’s cabin was preserved without incurring any particular extra danger for the large car.
But in the 1970s, the simple restraint systems – seatbelts – provided only moderate restraint and in the decades that followed, much effort went into developing restraint systems which would effectively reduce the injuries.