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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.

The EuroSID-2re (ES-2re) is an Anthropometric Test Device (ATD) from the automotive domain designed for lateral impact. Since the 2000’s, it has also been used by NATO armies to assess the risk of injury to armored vehicles occupants submitted to an Improvised Explosive Device (IED) attack. The resulting loading conditions from an explosion can vary a lot in term of impact velocity and duration. They range from high velocity impacts (~28 m/s), characterized by a short duration (~10 ms) corresponding to cases where the panel deforms under an explosion, to low velocity impacts (~4 m/s), ch aracterized by a long duration (~50 ms) similar to the automotive domain. The goal of the study is to develop a shoulder injury criterion for the EuroSID-2re that is relevant over the whole loading conditions spectrum of the military domain. For that purpose, thirty-three laboratory ES-2re tests are conducted to replicate four PMHS shoulder impactor test series from the literature.

Several studies, available in the literature, were conducted to establish the most relevant criterion for predicting the thoracic injury risk on the THOR dummy. The criteria, such as the maximum deflection or a combination of parameters including the difference between the chest right and left deflections, were all developed based on given samples of Post Mortem Human Subject (PMHS). However, they were not validated against independent data and they are not always consistent with the observations from field data analysis. For this reason, 8 additional PMHS and matching THOR tests were carried out to assess the ability of the criteria to predict risks. Accident investigations showed that a reduction of the belt loads reduces the risk of rib fractures. Two configurations with different levels of force limitation were therefore chosen. A configuration representing an average European vehicle was chosen as a reference.

In the past, many studies have been dedicated to the comparison of dummies and human body behavior in different impact conditions. However, the complex boundary conditions generated by a complete restraint system render it difficult to compare both human surrogates in a car environment. Furthermore, the great dispersion among car occupants is an additional difficulty which is difficult to overcome with experimental studies, Computer simulation, as far as a validated human body model is available, gives a unique possibility to assess the influence of some restraint parameters, whilst all remaining parameters are unchanged. To this end, a 3D finite element human body model validated in many different impact configurations against a large number of biomechanical corridors was used. In order to compare responses, models of Hybrid III and Eurosid 1 dummies were also used.

Despite the increasing knowledge of the thorax mechanics in impact loadings, the effects of inter-individual differences on the mechanical response are difficult to take into account. For example, the biofidelity corridors for the small female or large male are extrapolated from the midsize male corridors. The present study reports on the results of new tests performed on small female Post Mortem Human Subjects (PMHS), and compares them with test results on midsize male PMHS. Three tests in pure side impact and three tests in forward oblique impact were performed on the thorax of small female specimens. The average weight and stature were 43 kg and 1.58 m for the small female specimens. The initial speed of the impactor was 4.3 m/s. The mass and the diameter of the impactor face were respectively 23.4 kg and 130 mm. The instrumentation and methodology was the same as for the tests published in 2008 by Trosseille et al. on midsize male specimens.

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.

As more and more active restraint devices are added by vehicle manufacturers for occupant protection, the history of driver frontal airbags illustrates that the design performance of such devices for in-position (IP) occupants often have to be limited in order to reduce their aggressiveness for out-of-position (OOP) situations. As of today, a limited number of publications dealing with FE simulation of airbag deployment for OOP are available. The objective of our study was to evaluate the feasibility of airbag deployment simulations based on an extensive set of well-defined physical test matrix. A driver frontal airbag was chosen (European mid-size car sample) for this study. It was deployed against a force plate (14 tests in a total of 6 configurations), and used with Hybrid III 50th percentile dummy (HIII) in OOP tests (6 tests, 4 configurations). Special attention was paid to control the boundary conditions used in experiments in order to improve the modelling process.

The EuroSID-2re (ES-2re) Anthropomorphic Test Device (ATD) commonly known as the crash test dummy is also used in the military domain to assess the risk of injury of armored vehicles occupants from lateral impact. The loading conditions range from low velocity - long duration impacts (4 m/s - 50 ms) similar to the automotive domain, to high velocity - short duration impacts (28 m/s - 3 ms) corresponding to cases where the panel deforms under an explosion. The human shoulder response to lateral impact was investigated at bounds of the loading condition spectrum previously mentioned, and also at intermediate conditions (14 m/s - 9 ms) in previous studies. The aim of the current study is to provide additional insight at the intermediate loading conditions which are not found in the literature.

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.

The reality of the autonomous vehicle in a near future is growing and is expected to induce significant change in the occupant posture with respect to a standard driving posture. The delegated driving would allow sleeping and/or resting in a seat with a reclined posture. However, the data in the literature are rare on the body kinematics, human tolerance, and injury types in such reclined postures. The current study aims at increasing the knowledge in the domain and providing useful data to assess the relevance of the standard injury assessment tools such as anthropomorphic test devices or finite element human body models. For that purpose, a test series of three male Post-Mortem Human Subjects (PMHS) were performed in frontal impact at a 13.4 m/s delta V. The backseat inclination was 58 degrees with respect to the vertical axis. The semi-rigid seat developed by Uriot et al. (2015) was used with a stiffer seat ramp.

This study focuses on the phenomenon of lap belt slip on the iliac spines of the pelvis, commonly named “submarining ”. The first objective was to compare the interaction between the pelvis and the lap belt for both dummies and Post Mortem Human Subjects (PMHS). The second objective was to identify parameters influencing the lap belt hooking by the pelvis. For that purpose, a hydraulic test device was developed in order to impose the tension and kinematics of the lap belt such that they mimic what occurs in frontal car crashes. The pelvis was firmly fixed on the frame of this sub-system test-rig, while the belt anchorages were mobile. Fourteen tests on four Post-Mortem Human Subjects (PMHS) and fifteen tests on the THOR NT, Hybrid III 50th and Hybrid III 95th percentile dummies were carried out. The belt tension was kept constant while a dynamic rotation was imposed on the belt anchorages.

Despite the increasing knowledge of the thorax mechanics, the effects of inter-individual differences on the mechanical response are difficult to take into account. Several methods are available in the literature to refine the biofidelity corridors or to extrapolate them to other populations (eg: children, small females, large males). Because of the lack of concrete cases, the relevance of the assumptions is rarely investigated. In 2014, Baudrit et al. published data on thorax dynamic responses of small female and midsize male Post Mortem Human Subjects in side and forward oblique impact tests. The impactor mass was 23.4 kg for all the tests and the nominal impact speed was 4.3 m/s. The diameter of the rigid disk was 130 and 152 mm respectively for the small female specimens and for the midsize male specimens. The authors found that the maximum impact force was a function of the total body mass for each loading.

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.

Many studies have reported multiple rib fractures sustained by an Out-of-Position (OOP) driver subjected to a frontal airbag deployment, but the injury mechanisms and thresholds remain unclear. Two successive phases occur during the bag deployment: punch-out loading of the thorax, followed by a membrane effect (Horsch et al. 1990). The aim of this study was to investigate the thoracic injuries generated by each phase separately. Tests of nine post-mortem human surrogates (PMHS) were carried out on a static test bench using a driver side airbag module described by Petit et al. (2003). The steering wheel was replaced by a plate in order to increase the loading generated by the airbag. Three loading configurations were performed: membrane only, punch-out only, and both types combined. The membrane-only tests were performed with the thorax initially positioned at 13, 78 and 128 mm from the plate in order to vary the load magnitude.