F2008-08-055
The Development of a Vehicle Collision Mitigation Control System though Multi-Body Modelling
The ever important development of automotive crash mitigation systems has, over recent years, lead to the development of Advance Driver Assistance (ADA) systems. These systems use a variety of approaches to help avoid vehicle collision from occurring. However, these systems are still far from being able to prevent all collisions from occurring. Studies have already shown that even slight misalignments of the key vehicle structural components can greatly affect the outcome of a collision. Manufacturers and governing bodies have already begun to target this problem area with standards for structural design being made across the vehicle range. However, the effects of vehicle´s dynamic characteristics can have a significant effect on vehicle compatibility. This is particularly noticeable in the case of vehicle under-ride in vehicle following collisions, where the pitch effect caused by the vehicles braking causes a vertical misalignment between the front structure of the impact vehicle and the rear of the target vehicle. Little current literature exists that discusses these key factors of the development of vehicle crash mitigation systems and current crash testing does not study the effects that vehicle dynamics may have on a vehicle´s crashworthiness. The research detailed in this paper aims to use vehicle dynamic control systems to optimize the vehicle´s dynamic characteristics for an impending collision. This will utilize the detection systems developed for these ADA systems, to detect when an imminent collision has become unavoidable and provide information about the pending collision. To perform such studies, it is important to have a vehicle dynamic simulation that can also include the vehicle crash structural dynamics. These factors are key to analysing the point-of-impact and post-impact vehicle dynamics and the effects on the outcome of the impact. This paper outlines the development of a unique multi-body vehicle dynamic crash analysis model. This enables the analysis of a generic vehicle dynamic model, together with a simplified crash model, so that the effects of a variety of dynamic control approaches can be analysed. This will give a valuable insight into the effects of vehicle dynamic control on the collision severity. Results show that this simple and fast method of simulating both the vehicle dynamics and crash dynamics in a simple multi-body model can be an effective and accurate tool for generic vehicle analysis. Results also show that even simple vehicle dynamic controls during the pre-impact, impact and post-impact stages of the collision can have a significant effect on the impact severity.
Session: Advanced Safety Systems II