Crash Simulation and Occupant Safety Analysis Using the Finite Element Method 1999-01-3056
Over the last decades the vehicle safety research, and in consequence the developments efforts has made passenger cars safer and safer. Since a few years, also for trucks design aspects has become more and more important.
This paper describes a series of simulations for various crash conditions of a light truck in order to analytically evaluate the driver airbag must-fire and no-fire conditions for the vehicle and in addition the occupant kinematics for the driver. These conditions represent internal company standards for evaluating cab-over-engine (COE) type trucks.
These standards were developed during years and represent typical crash conditions for European roads. An additional high speed (35 km/h) barrier test is considered as an extreme worst case.
The no-fire simulations consist of a low speed, 15 km/h, crash against a rigid barrier, and a high-speed crash, 50 km/h, against a traffic-light pole. The must-fire conditions are evaluated with a 35 km/h crash against a rigid barrier, a 30 km/h full frontal crash against a 20 ton parked trailer and a 30 km/h, 50% offset (passenger-side) crash against the same trailer.
The occupant kinematics analysis uses the truck deceleration pulse according to the simulated pulse signal for the 35 km/h barrier crash. Besides being the worst case, it is the situation which has best correlation with real tests.
The analysis was conducted using durability FE models that where then converted to crash models. Although only the 35 km/h pulse signals results are presented, the pulses for all the simulations were thoroughly analyzed.
Performance criteria can be well evaluated and visualized using powerful post-processor tolls which allows the designer to take important conclusions and optimize the structure performance on the very early stage of development.