Abstract
Current market demand requests an enormous range of vehicle types, from small city cars, touring sedans up to large family-size vans. Latest fuel consumption and emissions requirements have resulted in a very high need for small cars and low-cost cars in particular. Therefore the challenge in designing of small cars is not only eco-friendliness, but also – more particularly – safety.
Mercedes-Benz began to focus intensively on the safety of compact vehicles in the 1990s. Innovative vehicle concepts were formulated, with the development of the A-Class and the smart, revolutionizing the safety of smaller vehicles. Until then, small cars had been seen as less safe than comparatively larger vehicles, because of their physical disadvantages, particularly their lower mass. Mercedes-Benz was faced with the task of resolving these conflicting objectives. This challenge was compounded by the need for completely new approaches for the smart, a car with a total length of just 2.50 metres. Small, light vehicles are inevitably subjected to comparatively higher relative change in velocity in collisions with larger and heavier vehicles. However, appropriately designed small vehicles with a small crumple zone, but an extremely rigid passenger cell and extensive internal forward displacement capacity for the vehicle occupants, can offer a good level of protection. A high level of safety obviously also requires offering the same or similar safety equipment equally at least as good as that in larger vehicles. ABS, ESP, airbags, belts with tensioners and force limiters are essential features complementing an intelligent vehicle design. This paper describes the challenges and the basic factors in design for safety of small cars, based on the example of the smart car. The main focus is on the specific characteristics of vehicle-vehicle frontal collisions. Finally, the paper looks at the performance of the smart in actual real accident situations. Accident statistics from more than ten years of smart cars on the road provide the basis for some reliable conclusions on the safety characteristics of such vehicles.
Keywords: small car, safety, compatibility, real accident, real life safety