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Far side has been identified in the literature as a potential cause of numerous injuries and fatalities. Euro NCAP developed a far side test protocol to be performed to assess adult protection. A monitoring phase was undertaken between January 2018 and December 2019, and the far side assessment will become part of the rating for all vehicles launched in 2020 onward. A test buck was developed and 6 paired WorldSID / Post Mortem Human Subjects (PMHS) were subjected to the test protocol proposed by Euro NCAP to contribute to the development of limits. The buck consisted of a rigid seat and a rigid central console covered with 50 mm of Ethafoam TM 180 with a density of 16 kg/m3. The buck was mounted on the sled with an angle of 75° between the X axis of the vehicle and the X axis of the sled. The peak head excursion was compared between PMHS and the WorldSID dummy. It was found reasonably similar. However, the dummy repeatability was found to be poor.

In the last decade, extensive efforts have been made to understand the physics of submarining and its consequences in terms of abdominal injuries. For that purpose, 27 Post Mortem Human Subject (PMHS) tests were performed in well controlled conditions on a sled and response corridors were provided to assess the biofidelity of dummies or human body models. All these efforts were based on the 50th percentile male. In parallel, efforts were initiated to transfer the understanding of submarining and the prediction criteria to the THOR dummies. Both the biofidelity targets and the criteria were scaled down from the 50th percentile male to the 5th percentile THOR female. The objective of this project was to run a set of reference PMHS tests in order to check the biofidelity of the THOR F05 in terms of submarining. Three series of tests were performed on nine PMHS, the first one was designed to avoid submarining, the second and third ones were designed to result in submarining.

The study firstly aimed at looking whether sacroilium (SI) fractures could be sustained as unique pelvic injuries in side impact real world automotive accidents. Secondarily, the sacroilium fractures observed in conjunction with other pelvic fractures were analyzed to investigate the existence of injury association patterns. Two real world accident databases were searched for SI fractures. The occupants selected were front car passengers older than 16, involved in side, oblique or frontal impact, with AIS2+ pelvic injuries. In frontal impact, only the belted occupants were selected. The cases were sorted by the principal direction of force (dof) and the type of pelvic injury, namely SI, pubic rami, iliac wing, acetabulum, pubic symphysis, and sacrum injuries. The relation between SI and pubic rami injuries were investigated first. The first database is an accident database composed of cases collected in France by car manufacturers over a period of approximately 40 years.

Petit et al. 2015 and Lebarbé et al. 2016 reported on two studies where the injury mechanism and threshold of the sacroiliac joint were investigated in two slightly oblique crash test conditions from 18 Post Mortem Human Subjects (PMHS) tests. They concluded that the sacroiliac joint fractures were associated with pubic rami fractures. These latter being reported to occur first in the time history. Therefore it was recommended not to define a criterion specific for the sacroiliac joint. In 2012, injury risk curves were published for the WorldSID dummy by Petitjean et al. For the pelvis, dummy and PMHS paired tests from six configurations were used (n = 55). All of these configurations were pure lateral impacts. In addition, the sacroiliac joint and femur neck loads were not recorded, and the dummy used was the first production version (WorldSID revision 1). Since that time, the WorldSID was updated several times, including changes in the pelvis area.

The aim of this study was to investigate the sacroiliac joint injury mechanism. Two test configurations were selected from full scale car crashes conducted with the WorldSID 50th dummy resulting in high sacroiliac joint loads and low pubic symphysis force, i.e. severe conditions for the sacroiliac joint. The two test conditions were reproduced in laboratory using a 150-155 kg guided probe propelled respectively at 8 m/s and 7.5 m/s and with different shapes and orientations for the plate impacting the pelvis. Nine Post Mortem Human Subject (PMHS) were tested in each of the two configurations (eighteen PMHS in total). In order to get information on the time of fracture, eleven strain gauges were glued on the pelvic bone of each PMHS. Results - In the first configuration, five PMHS out of nine sustained AIS2+ pelvic injuries. All five presented sacroiliac joint injuries associated with pubic area injuries.

Sled tests focused on pelvis behavior and submarining can be found in the literature. However, they were performed either with rigid seats or with commercial seats. The objective of this study was to get reference tests to assess the submarining ability of dummies in more realistic conditions than on rigid seat, but still in a repeatable and reproducible setup. For this purpose, a semi-rigid seat was developed, which mimics the behavior of real seats, although it is made of rigid plates and springs that are easy to reproduce and simulate with an FE model. In total, eight PMHS sled tests were performed on this semi-rigid seat to get data in two different configurations: first in a front seat configuration that was designed to prevent submarining, then in a rear seat configuration with adjusted spring stiffness to generate submarining. All subjects sustained extensive rib fractures from the shoulder belt loading.

The WorldSID dummy can be equipped with both a pubic and a sacroiliac joint (S-I joint) loadcell. Although a pubic force criterion and the associated injury risk curve are currently available and used in regulation (ECE95, FMVSS214), as of today injury mechanisms, injury criteria, and injury assessment reference values are not available for the sacroiliac joint itself. The aim of this study was to investigate the sacroiliac joint injury mechanism. Three configurations were identified from full-scale car crashes conducted with the WorldSID 50th percentile male where the force passing through the pubis in all three tests was approximately 1500 N while the sacroiliac Fy / Mx peak values were 4500 N / 50 Nm, 2400 N / 130 Nm, and 5300 N / 150 Nm, respectively. These tests were reproduced using a 150 kg guided probe impacting Post Mortem Human Subjects (PMHS) at 8 m/s, 5.4 m/s and 7.5 m/s.

Seven Post Mortem Human Subjects were submitted to three low velocity impacts (v=1.5 m/s) to the right shoulder at three different angles in the horizontal plane (−15°, 0°, +15°). Then, the left shoulder was submitted to a purely lateral high velocity impact (v=3, 4, 6 m/s). The load was delivered by a 23.4 kg impactor fitted with a rigid rectangular impacting plate. Shoulder and thoracic bone structures were equipped with tri-axial accelerometers and photographic markers, whose trajectories were tracked in 3D by seven high-speed cameras. The results were scaled in order to account for the differences between the subjects’ anthropometry and to define response corridors for the evaluation of the dummies’ shoulders. Impact forces as well as several shoulder deflections were analyzed with respect to each subject’s injury survey in order to find the most relevant parameters for the prediction of injuries.

The results of biomechanical testing of the WorldSID prototype dummy are presented in this paper. The WorldSID dummy is a new, advanced Worldwide Side Impact Dummy that has the anthropometry of a mid-sized adult male. The first prototype of this dummy has been evaluated by the WorldSID Task Group against previously established corridors for its critical body regions. The response corridors are defined in the International Organization of Standardization (ISO) Technical Report 9790. The prototype is the first version of the WorldSID dummy to be built and tested. This dummy has been subjected to a rigorous program of testing to evaluate, first and foremost its biofidelity, but also its repeatability. Following this initial evaluation, any required modifications will be incorporated into a pre-production version of the WorldSID dummy so that it rates “good” to “excellent” on the ISO dummy biofidelity scale – a rating exceeding that of all current side impact dummies.