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In highly automated vehicles (HAVs), new seat configurations may be desirable to allow occupants to perform new activities. One of the current HAV concepts is the swiveled seat layout, which might facilitate communication between occupants. The main objective of this study was to investigate the effects of seat swiveling angles on occupant kinematics and injury risk predicted by a Human Body Model (HBM) during a frontal impact. A detailed 50th percentile male HBM (GHBMC M50-O) was subjected to two frontal crash pulses in a sled setup. The model was positioned on a semi-rigid seat and restrained using a pre-inflated airbag and a three-point seatbelt. Simulations included four seat swiveling angles (0, -10, -20, and -30 degrees), three occupant positions (Sedan driver, large VAN driver or Laptop user), two airbag initial locations (nominal or matching the head Y location), and the inclusion of lateral supports on the seat pan.

Child dummies used in certification dynamic tests have not been improved since their marketing and their approval as European regulation dummies. Their main shortcoming lies in a too high and therefore unrealistic stiffness of the torso front part. The paper addresses a study carried out in the aim of solving this problem. It includes two parts: in a first section, the changes brought to the dummy torso and intended to improve its biofidelity and to reduce stiffness drastically are described. In order to reach such an objective, the lower part of the upper torso was remodelled; the pelvis profile was redefined and the geometrical and mechanical characteristics of the foam used for the abdominal insert were changed. The results obtained using two transducers installed in the abdominal section are then presented. The measurement principle of the first transducer consists in a pressure measurement, and the principle of the second one in a load measurement.

Accident studies show that frontal collisions, both as regards the number of people killed and those seriously-injured, are by far the type of crash with the most serious consequences. In order to improve this situation, it is necessary to ensure that the means used to restrain occupants work as efficiently as possible, whilst preserving the occupant compartment and thus by eliminating intrusion on the occupant restrained by seat-belts and pretensioners. In frontal collisions where vehicle intrusion is minor, the main lesions caused to occupantss are thoracic, mainly rib fractures resulting from the seat-belt. In collisions where intrusion is substantial, the lower members are particularly vulnerable. In the coming years, we will see developments which include more solidly-built cars, as offset crash test procedures are widely used to evaluate the passive safety of production vehicles.

Child restraint systems (CRS) for cars are intended to protect children in the case of a car accident. Unfortunately their effectiveness is still too low: in the range 30–50 % when it would be expected to be much higher. The low effectiveness of child restraint systems can partly be explained for the youngest passengers by their greater cervical vulnerability and for the oldest (from 3 to 12 years old) by the morphological immaturity of the pelvis. However, tools available to evaluate the effectiveness of CRS are very poor, as well as knowledge on injury mechanisms and criteria. The CREST project was created to develop the knowledge on child behaviour and tolerances, the final aim being to propose new test procedures for determining the effectiveness of CRS using instrumented child dummies. Eleven partners were involved, namely Fiat Auto-SpA (with Elasis), INRETS, PSA Peugeot Citroën, Renault, TNO Automotive, TUB, RICE, BAST, GDV, MUH, VTI.

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.

This paper presents comprehensive dorsiflexion responses and tolerances obtained from two types of dynamic tests on whole cadavers conducted at the Renault/PSA Laboratory of Accidentology and Biomechanics (LAB): sled tests and sub-system tests. In all the experiments (on whole cadavers), forces and moments within the ankle joint were accurately measured by means of a custom-designed 6-axis load cell implanted in the tibia, leaving all surrounding musculature intact. The results derived from both the sled tests and the subsystem tests are very similar. Moment-rotation curves are provided for the ankle joint. The force in the Achilles tendon which is not directly measured is calculated using the forces applied to the foot and the forces measured in the tibia.

A new approach has been developed to facilitate the measurement of head angular acceleration in automobile crash tests. It consists of two parts: an array of 12 linear accelerometers mounted in a Hybrid III dummy head and an electronic signal processor mounted on the dummy spine. The accelerometer outputs are led to conventional data acquisition equipment and also to the signal processor which digitizes the raw acceleration signals, stores them, and computes the 3-D angular acceleration. This acceleration and the 3-D linear acceleration of the head c.g. are available in real time or post test. The equipment has been evaluated on a mini-sled, with various configurations of head loading and kinematics, and also in Hyge sled tests performed at 40 km/h with a 3 point belted Hybrid III dummy. The angular accelerations returned by the signal processor in both test settings corresponded closely to those computed off-line from the raw data.

Numerous cadaver tests have been performed in the past to define the behaviour and tolerance of the thorax under side impact conditions. To take into account the various test conditions and measurements techniques or parameters, a lumped parameter model is used to reproduce these tests and thus to compute the protection criteria in the same way. The correlation between the calculated criteria and the observed injuries is then analysed as a basis for discussion of their consistency and relevance. The second part of the paper deals with the transposition of tolerance criteria to the Eurosid 1 dummy, using simulation tests under different conditions (impactor test, free-fall test, imposed velocity). The results show that this transposition depends on the test conditions, because of the limited biofidelity of the Eurosid 1 dummy.

The anatomical dimensions, inertial properties, and mechanical responses of cadaver leg, foot, and ankle specimens were evaluated relative to those of human volunteers and current anthropometric test devices. Dummy designs tested included the Hybrid III, Hybrid III with soft joint stops, ALEX I, and the GM/FTSS lower limbs. Static and dynamic tests of the leg, foot, and ankle were conducted at the laboratories of the Renault Biomedical Research Department and the University of Virginia. The inertial and geometric properties of the dummy lower limbs were measured and compared with cadaver properties and published volunteer values. Compression tests of the leg were performed using static and dynamic loading to determine compliance of the foot and ankle. Quasi-static rotational properties for dorsiflexion and inversion/eversion motion were obtained for the dummy, cadaver, and volunteer joints of the hindfoot.

Experimental crash data are examined to determine how vehicle rigidity influences seat belt operation. Total occupant braking distance is maximized when a vehicle has high frontal deformation, as belt loading occurs at impact. However, for any given vehicle optimum conditions occur when: 1. Dead time between impact and belt loading is minimized. 2. Seat belt webbing characteristics are matched to vehicle structure to use maximum available braking distance.

Children are often involved in automotive accidents especially as car occupants. Their protection presents particular problems in the first years of life, due to large changes in their morphology and behaviour. The aim of this paper is to contribute towards the development of a better evaluation of the child's tolerance to impact. Car accident investigations are analysed to bring information on injury mechanisms and severities. Free fall accidents are other sources of data used to correlate injuries with impact conditions. Theoretical analysis is considered for extrapolation of experimental data obtained from adult humans and animal surrogates. Then crash simulations with child cadavers and primates restrained in child seats are analysed and the estimation of tolerance levels for children is discussed.

The European Side Impact Dummy “EUROSID”, and the Sid Impact Dummy “SID” were extensively tested in the frame of an experimental program conducted by the C.C.M.C. in Europe. The principal objective of this study was the evaluation of the biofidelity of both dummies according to impact response requirements selected by the ISO/TC22/SC12/WG5 experts, these requirements being, at the present the best and most updated technical informations available to assess the biofidelity of a dummy in side impact. The test matrix comprised 40 impactor tests, 75 free fall tests and 7 sled tests. Each dummy region covered by ISO requirements was tested. In this paper the performance of EUROSID and SID dummies are, on the basis of available results, compared with human response data proposed by ISO.

In order to obtain data about human head tolerance, the APR Laboratory of Biomechanics has developed a specific methodology for volunteer boxers. These ones are used because they expose themselves, in their normal body activities, to direct head impacts similar in nature to those experienced by vehicle occupants under crash conditions. This paper describes the specific experimental technique that permits association of the severity of the blows, measured in terms of physical parameters, to corresponding physiological effects, measured in medical terms.

Although the neck is one of the least frequently injured body regions, it does play a considerable role in the solicitations of the head in side impact. It can, in fact, be said that the kinematic and dynamic conditions that govern, for instance, a head impact against a vehicle structure depend on the cervical segment. With a view to characterizing such conditions, i.e. head and neck responses, the LPB-APR conducted a research program including sled tests involving cadavers. These tests were conducted at a low and high G-level sled deceleration, respectively, with the low-violence tests being carried out following collaboration with the Naval Biodynamics Laboratory (New Orleans). Such tests enable direct comparison between volunteer data and cadaver data. The scope of this paper is to present a synthesis of the data obtained from LPB-APR low and high G-level tests, including, in particular, data obtained from new high severity tests.

In view of the lack of data concerning child protection, an accidentological and experimental work was engaged. The goal of this international research involving experts from seven countries was two-fold: In one hand, to establish protection principles, gathering and analysing real crashes involving restrained children. In the other hand, to identify and to quantify injury mechanisms in order to increase knowledge on child tolerances. To realize this second part, real crash reconstructions were performed, in order to correlate observed injuries with recorded parameters on dummies. This paper mainly presents four real crashes with the corresponding reconstructions. A special analysis of injury mechanisms in relation with their respective pertinent parameters is then proposed.

In the ECE 127 Regulation on pedestrian leg protection, as well as in the Euro NCAP test protocol, a legform impactor hits the vehicle at the speed of 40 kph. In these tests, the knee is fully extended and the leg is not coupled to the upper body. However, the typical configuration of a pedestrian impact differs since the knee is flexed during most of the gait cycle and the hip joint applies an unknown force to the femur. This study aimed at investigating the influence of the inertia of the upper body (modelled using an upper body mass fixed at the proximal end of the femur) and the initial knee flexion angle on the lower limb injury outcome. In total, 18 tests were conducted on 18 legs from 9 Post Mortem Human Subjects (PMHS). The principle of these tests was to impact the leg at 40 kph using a sled equipped with 3 crushing steel tubes, the stiffness of which were representative of the front face of a European sedan (bonnet leading edge, bumper and spoiler).

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 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.

The Test Device for Human Occupant Restraint (THOR) is an advanced crash test dummy designed for frontal impact. Originally released in a 50th percentile male version (THOR-50M), a female 5th version (THOR-05F) was prototyped in 2017 (Wang et al., 2017) and compared with biofidelity sub-system tests (Wang et al., 2018). The same year, Trosseille et al. (2018) published response corridors using nine 5th percentile female Post Mortem Human Subjects (PMHS) tested in three sled configurations, including both submarining and non-submarining cases. The goal of this paper is to provide an initial evaluation of the THOR-05F biofidelity in a full-scale sled test, by comparing its response with the PMHS corridors published by Trosseille et al. (2018). Significant similarities between PMHS and THOR-05F were observed: as in Trosseille et al. (2018), the THOR-05F did not submarine in configuration 1, and submarined in configurations 2 and 3.