The concept of designing all road vehicles to be compatible in terms of their impact with each other at an agreed height above ground level came to the fore at the 14th ESV Conference. In particular this is to be done to minimise intrusion and consequent severe injuries, especially to occupants of the smaller vehicle involved, which is assumed to be a small car. The present paper discusses some of the more practical aspects of achieving this compatibility. It is suggested that the front sections of all impacting structures at the fronts of vehicles should have similar crushing characteristics up to an agreed depth of crush, maybe 700mm, whether they be cars, coaches, vans or goods vehicles. The question is how can this structure be designed. It is proposed that perhaps 150mm behind the softer front face designed to alleviate impacts with pedestrians and then impacts with the sides of cars, there should be a rectangular frame supported by corner posts. The corner posts would crush back to provide the main impact resistance at the corners of the front. The sides would be strong in tension and would be the structures which would actually interact with the frame of the opposing vehicle. They would transfer the impact loads back to the corner posts which would control the crush characteristics. It is assumed that only the perimeter of the rectangular frame contains major impact resisting structures. The role of the engine is considered separately. The rationale behind this layout is discussed together with a number of details about applying it to various types of vehicles and to their sides and rears as well as to their fronts. (A)
Abstract