Evaluation of Occupant Protection During the Crash Phase Considering Pre-Crash Safety Systems –Results from the EC-Funded Project ASSESS

Since integrated safety systems combine active and passive safety elements in one safety system, it is necessary to define new procedures to evaluate vehicle safety from the overall system point of view. The main goal of the ASSESS project is to develop harmonized and standardized assessment procedures for collision mitigation and avoidance systems. In ASSESS, procedures are developed for: driver behaviour evaluation, pre-crash system performance evaluation, crash performance evaluation, socio-economic assessment. This paper will concentrate on the activities related to the crash evaluation. The objective is to perform simulations, sled tests and crash tests in order to understand the influence of the activation of the pre-crash systems on the occupants’ injuries during the crash phase. When a traffic accident is unavoidable, pre-crash systems work on various safety devices in order to improve the vehicle occupants’ protection. Braking assistance and adaptive restraint systems are the main pre-crash systems whose effect on the occupants’ protection will be described in this paper. The results will be a description of the effect of the activation of the pre-crash systems on the crash phase. Additionally, a set of recommendations for future methodology developments will be delivered. Furthermore, a first approach to the study of the effect of the pre-crash systems activation on the occupants’ protection when the impact is unavoidable will be presented. This effect will be quantified using the biomechanical values obtained from the simulation and testing activities and their related injury risks. Simulation and testing activities will consider the following scenarios: (1) No activation of any pre-crash system; and (2) Activation of one or a combination of several pre-crash systems. In this way, differences in the results obtained from different scenarios will show the effect of each pre-crash system separately during the crash phase. The set of activities developed in this research project is limited by the fact that with the given resources only a limited number of vehicle models could be investigated. In addition, there are also limitations related to the injury risk curves and the passive safety tools currently on the market. The paper will present a complete analysis of the effect of pre-crash systems during the crash phase when the impact is unavoidable. Details, limitations and first application experience based on a few examples will be discussed. Currently, there is not any regulation, assessment program, or other similar official procedure able to assess pre-crash systems during the crash phase. This project comprises phases of traffic accidents which have been historically analysed separately, and aims to evaluate them taking into account their interrelationship. ASSESS is one of the first European projects which deals in depth with the concept of integrated safety, defining methodologies to analyse vehicle safety from a global point of view.