The marks left by the vehicle prior to impact, rollover, or other event, are important forensic evidence reconstruction of motor vehicle accidents. Often these tyre marks have some curvature that is measured and used to calculate the speed of vehicles prior to the event. This calculation is based on the coefficient of friction of the tyre/road interface and the radius of curvature of the vehicle center of gravity path. There is a controversy about the validity of this approach. To explore this theory, a test vehicle was driven through a series of manoeuvres that produced yaw marks for direct comparison of actual vehicle velocity to the velocity calculated by the critical speed formula. Tests results formula. Tests results show the critical speed formula is inaccurate for most circumstances and does not correctly describe vehicle limit performance behaviour. (A)
Samenvatting