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This paper describes the development of a sled-to-sled test methodology to simulate the occupant responses in different side impact cart test modes. For evaluation of various inflatable restraints (Thorax SAB, Head-Thorax Combo SAB, Pelvis-Thorax Combo SAB), the simulation of ‘gap closure’ between dummy and door is desirable to achieve satisfactory SAB performance, besides obtaining good correlation of occupant responses between full-vehicle tests and sled tests. This methodology uses a combination of three sleds - Bullet, Door, and Seat sleds to simulate the entire door velocity profile in two phases - Phase I: Gap Closure till Door-Dummy contact occurs, Phase II: Door-to-Dummy contact till separation. The initial pre-crash distance between dummy-to-door trim is achieved by positioning the Door sled relative to the Seat sled (with dummy).

A dynamic component test methodology using a door sub-system was developed to simulate the outside door handle/latch responses (accelerations and deformations) as in a full-vehicle NHTSA FMVSS 214 side impact test. The test methodology consists of a door sub-system (with door inner components) which is allowed to pivot by means of a hinge at the top of the door. The lateral structural load path affecting the door/rocker response was accounted and simulated (obtained from full-vehicle FE analysis) in this methodology by means of an energy absorbing material (Aluminum honeycomb) of predetermined stiffness. A bullet sled simulating the Moving Deformable Barrier (MDB) surface and stiffness at the same relative location to the door/rocker (as in full-vehicle test) strikes the stationary hinged door at an initial velocity of approx. 30 mph (longitudinal component of crab cart velocity of 33.5 mph).

The aim of this study was to understand the behavior of Eurosid rib module and its components under different impact conditions. This was achieved by impacting the single rib module at two different velocities of 7.6m/s and 10.8m/s at three impact angles of 0, +30 and -30 deg corresponding to each velocity. All tests were done using a 1.86 kg (4.1 lbs), 152 mm (6″) circular impactor on the Monterey facility (Linear impactor) and some of the tests were filmed at 5000 fps. Tests were also done with and without tuning spring to assess its contribution to the total rib response. The hydraulic damper and damper spring were dynamically tested at different velocities to obtain their individual characteristics of force-velocity and force-deflection respectively. Static force-deflection characteristics of all the four tuning springs and damper spring were also obtained. The results of single rib tests @ 0 deg were compared with the CAE models currently available in MADYMO-3D and RADIOSS.

This paper describes the development of a new component test methodology concept for simulating NHTSA side impact, to evaluate the performance of door subsystems, trim panels and possible safety countermeasures (foam padding, side airbags, etc.). The concept was developed using MADYMO software and the model was validated with a DOT-SID dummy. Moreover, this method is not restricted to NHTSA side impact, but can be also be used for simulating the European procedure, with some modifications. This method uses a combination of HYGE and VIA decelerator to achieve the desired door velocity profile from onset of crash event until door-dummy separation, and also takes into account the various other factors such as the door/B pillar-dummy contact velocity, door compliance, shape of intruding side structure, seat-to-door interaction and initial door-dummy distance.

The objective of this study was to determine dynamic tensile characteristics of various door trim materials and to recommend a practical test methodology. In this study, Polypropylene (PP) and Acrilonitryl Butadiene Styrene (ABS) door trim materials were tested. Slow speed (quasi-static-0.021 mm/s) and high speed tests were conducted on a closed loop servo-hydraulic MTS system. The maximum stress of these materials increased from quasi-static to dynamic test conditions (as much as 100%). The dynamic stiffness of PP increased two times from quasi-static tests. No significant change in stiffness was observed for ABS during quasi-static and dynamic tests at different strain-rates. Quasi-static and medium strain-rate (10-20 mm/mm/s) tests may be adequate in providing data for characterizing the dynamic behavior of trim materials for CAE applications. Strain gages can be used to measure the quasi-static and in some cases, dynamic strain.