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‘Active safety systems’ are actively being developed to prevent collisions. The integration of ‘active safety systems’ and traditional ‘passive safety systems’ such as seatbelt and airbags is an important issue. The ‘Integrated safety’ performance is that comprehensively controls the performance of ‘active’ and ‘passive’ safety systems to reduce occupant injuries. To develop ‘integrated safety’ performance, it is important to develop crash scenarios for autonomous vehicles. This study is about the development of ‘Estimation Tool of Occupant Injury Risk’ for deriving risk integrated safety scenarios focused on occupant injury. The results of random traffic simulation using ‘Virtual Prototype’ were used to select parameters, and ‘MADYMO Equivalent Simplified Vehicle Crash Analysis Model’ was used to derive F-D characteristics for each vehicle collision condition.

The paper presents a simulation methodology created to support an integrated safety system development process which was tested for the side impact collision load case. The methodology is based on the coupled and complementary use of two software packages: PreScan and Madymo. PreScan was utilized for designing two traffic scenarios and the sensing and control systems for the side collision recognition, while Madymo was utilized for assessing the effects of pre-crash deployment of thorax airbag. The collision conditions from the scenarios were used as input to define a Madymo side collision model of the host vehicle and to investigate and optimize several airbag deployment parameters: pre-crash deployment time, airbag permeability, vent hole size and vent hole opening time.

Across the world different regulations are applicable for side impact, each require a different restraint system approach. However it would be much more cost effective to develop one single restraint system suitable for all global requirements. An efficient methodology has been developed to optimize the restraint system for multiple load cases simultaneously, resulting in a restraint system specification that will ensure that global targets are met. The methodology combines the use of testing and efficient numerical simulation to find a solution in the most effective way.

Across the world different regulations are applicable for frontal impact, each require a different restraint system approach. However it would be much more cost effective to develop one single restraint system suitable for all global requirements. Flexible and reliable development approach has to be used for quick evaluations of various safety system configurations and conditions. An efficient methodology has been developed to optimize the frontal restraint system for multiple load cases simultaneously, Resultant restraint system specification to specification to meet global targets. The methodology combines the use of testing and MADYMO modelling techniques in combination with advanced DoE (Design of Experiments) analysis to find a solution in the most effective way. An example will be given for a optimised restraint design to meet European and US requirements.

A growing set of barrier tests has to be taken into account to design side impact restraints meeting worldwide safety requirements. This paper shows an efficient design process to meet side impact requirements using smart testing and simulation. While full vehicle FE structural analysis is widely used, model sizes have been increasing which prohibits efficient design optimisation. The use of Prescribed Structural Motion (PSM) provides an efficient alternative for restraint optimisation. The objective in a typical PSM simulation is to approximate a complex (CPU expensive) loading scenario by prescribing (a part of the) structural nodal positions in time. Results show that design modifications based on MADYMO PSM simulation provide the expected safety performance in hardware testing. Furthermore, it will be shown that the ModeFRONTIER optimisation and stochastics can be effectively used to optimize the design while taking design robustness into account.

The number of passenger cars equipped with side air bags is steadily increasing. With the aim of investigating the mechanical responses and the injuries of the arm under the influence of a side air bag, tests in probably higher injury risk configurations with dummies and cadavers were performed. The air bag was installed at the outer side of the seat back, with the subject seated in the driver or front passenger seat of a passenger car. During the inflation of the air bag, the left or right forearm of the subject was positioned on the arm rest while the upper arm made contact with the seat back edge. The volume of the thorax air bag was 15 litres and for the thorax-head air bag 28 litres. The dummy was instrumented at the thorax c.g. shoulder, elbow and wrist with triaxial accelerometers. In the cadaver, triaxial accelerations in three orthogonal directions were measured at the upper and the lower humerus, the upper radius and the lower radius and the first thoracic vertebrae.