The prerequisites for achieving effective driver protection and the influence of crash pulse shape in 56 and 80 km/h fully-distributed perpendicular frontal impacts were investigated. The pulses used were based on the basic external dimensions and properties of a midsize car. The analysis was carried out by combining mathematical analysis with mechanical sled tests. An analytical tool to generate synthetic realistic crash pulses was developed. Using the tool crash pulses for 56 and 80 km/h frontal impacts in which the initial deceleration level, due to buckling and the total stopping distance were varied. Buckling deceleration levels were varied between 200and 400 m/s2 and total stopping distances were varied between 0.5 and 0.9m. The implications of the shape of the frontal crash pulse and the design of the interior driver protection system for impact velocities of 56 and80 km/h were analytically studied using computer occupant simulation software. The most promising mathematical modelling results were subsequently evaluated by means of mechanical sled tests. Based on the model predictions injury risk assessments were made for the two different impact velocities. At 56 km/h impact velocity the analysis show that in relation to the FMVSS 208 injury criteria levels a very low injury risk for the driver is achievable with a conventional restraint system and a stopping distance of 0.5 m and an initial buckling zone of 0.3 m with a deceleration level of 200 m/s2. At 80 km/h impact velocity the computer analysis and the sled tests show that the dummy responses can be kept below what is stipulated in the FMVSS 208 with an advanced restraint system and a stopping distance of 0.7 m and a square wave type of pulse. That is also true if the stopping distance is increased to 0.9 m. For the covering abstract see ITRD E141569.
Abstract