Real Time Control of Restraint Systems in Frontal Crashes

It is generally accepted that the targets for fatality reduction in car accidents set by Governments in Europe, USA and Japan can only be met by using advanced technologies that will include a broad range of sensors to monitor the crash likelihood and severity, vehicle condition, occupant type and posture. Information provided by these sensors can be used to increase the effectiveness of restraint systems. On the basis of information on the vehicle and the occupant status during the crash event, restraint parameters such as belt force and airbag outflow could be controlled real-time in such a way that injury levels sustained by the occupants are minimized. Real-time control during the crash event enables restraint systems to adapt to real world conditions and offers improved performance in terms of injury reduction over a much broader range of impact scenarios.

This paper introduces the concept of real-time control of restraint systems and presents the results of a numerical study to assess potential reduction in terms of injury severity and injury-related costs provided by real-time restraint system control in real world conditions. Accident analysis was used to identify a number of real world relevant scenarios for a numerical study performed with MADYMO. A detailed compartment model with 50^th percentile male driver with and without real time control of the restraint system was used. The controlled restraint parameters were belt force and airbag outflow. Specifications for the belt and airbag actuators were determined and aspects such as use of pre crash information were investigated.