This paper presents a simulation methodology for developing new automotive safety systems in an integrated manner that ensures optimal exploitation of benefits of predictive sensing and occupant restraints.
The investigation was performed using the combination of available simulation techniques for modeling Advance Driver Assistance Systems (PreScan software) and simulating the behavior of dummies and real humans under certain load conditions (MADYMO software and Active Human Model (AHM)).
The methodology was applied to investigate the occupant protection in side impact collisions making use of pre-crash deployed safety systems, such as pre-crash thorax airbag, inflatable seat bolsters, movable seat and a combination of them. The impact load on the dummy was derived from the simulation of the full FE vehicle under Euro NCAP Side Impact Testing protocol conditions.
The results obtained showed the clear potential of adopting an integrated safety system for side impact protection applications. When the collision is detected in advance the time gained can be exploited to increase the overall occupant protection by deploying safety countermeasures prior to the crash. Keeping the occupant further from the intrusion zone, reducing the relative impact velocity and controlling the occupant motion when entering the in-crash phase were key to significantly reduce the injury risk.
To realize the above phenomena, different pre-crash concept occupant motion solutions were defined and investigated: pre-crash deployed thoracic airbag, pre-crash deployed side-bolsters and pre-crash deployed laterally moving seat. Additionally combinations of each solution were investigated. The simulation analysis showed the best protection is ensured by the system combined of side-bolsters and moving seat deployed before the collision, in which case the overall injury risk was lowered from 130% to 44%, when expressed as values normalized with respect to high performance Euro NCAP limits.