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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.

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.

Improvement in the accessibility assessment of the seatbelts using a Digital Human Model requires a precise description of driver belt donning movement and of the associated discomfort. In order for automotive designers to be able to simulate seatbelt reaching movement, a general approach of motion simulation for complex and specific tasks has been proposed in this paper. It consists of three steps: constitution of a structured database, selection of an appropriate movement and its adaptation to meet new constraints. From an experiment, a database of 644 movements of automotive seatbelt reaching movements has been built-up. In order to structure the database, the temporal and spatial characteristics of the trajectories of main markers (e.g. markers attached to the hand and the torso) as well as joint movements were analysed, allowing us to identify motion control strategies.

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.

Driving posture study is essential for the evaluation of the occupant packaging. This paper presents a method of reconstructing driver’s postures in a real vehicle using a 3D laser scanner and Human Builder (HB), the digital human modeling tool under CATIA. The scanning data was at first converted into the format readable by CATIA, and then a personalized HB manikin was generated mainly using stature, sitting height and weight. Its pelvis position and joint angles were manually adjusted so as to match the manikin with the scan envelop. If needed, a fine adjustment of some anthropometric dimensions was also preceded. Finally the personalized manikin was put in the vehicle coordinate system, and joint angels and joint positions were extracted for further analysis.

A new experimental seat was designed to investigate sitting biomechanics. Previous literature suggested links between sitting discomfort and shear force, however, research on this topic is limited. The evaluation of sitting discomfort derived from past research has been primarily associated with seat pressure distribution. The key innovative feature of the experimental seat is not only pressure distribution evaluation but shear forces as well. The seat pan of the experimental seat compromises of a matrix of 52 cylinders, each equipped with a tri-axial force sensor, enabling us to measure both normal and tangential forces. The position of each cylinder is also adjustable permitting a uniform pressure distribution underneath the soft tissue of the buttocks and thighs. Backrest, armrests, seat pan and flooring are highly adjustable and equipped with forces sensors to measure contact forces.

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.

Monitoring driver’s postures has extensive applications. The postural information could be used for the development of smart airbags, for detecting possible fatigue in long travel and for recognizing activities which may determine if the driver has enough time to take over the control in an intelligent vehicle when encountering hazardous situations. Microsoft Kinect is one of the best candidates for monitoring driver’s posture thanks to its innovative feature of real time motion capture without use of markers and its low cost. However, when body parts are partially occluded, the accuracy of Kinect data will drop markedly. Inspired by previous researches, the present work focused on testing a data driven approach for improving driver’s upper body movement reconstruction with a Kinect camera. Firstly, we organize a database of accurately captured driver poses from different motion clips with filtered structures, including a global motion graph and multiple local motion graphs.

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.

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.

In addition to three main commercial human models (Ramsis, Jack, Safework), there exists also many non-commercial ones used in research laboratories. Sometimes, it becomes necessary to convert motion data from one model to another. This occurs in the case of the European research project REALMAN. In this project, three models (Ramsis, Jack and Man3D) are used by different partners. As they have different kinematic architectures, we have to write converters allowing collected motion data to be used by all three human models. In this paper, we present the method developed for converting the data from the Human Solution's Ramsis to Man3D, a noncommercial model developed at INRETS. We have shown that it is possible to convert motion data from one manikin to another using a method based on skeleton model comparison.

This paper presents the first experiment managed within the framework of the regional French project ST2 (French acronym for Sciences and Technologies for Safety in Transports). This program aims to study human pre-crash behavior in order to improve the efficiency of passive safety protection systems. An experiment was carried out using a driving simulator of LAMIH for investigating drivers frontal pre-crash postural changes. A scenario of an unavoidable crash was designed. To increase the level of realism during the crash, a real impact was added between the windscreen and a foam rubber block in addition to a truck horn sound. Risk car driver postures just before a frontal crash have been determined. The results have shown that none of the subjects adopted the standardized driving position during the collision and 30% of the subjects adopted a position with the left hand placed in front of steering wheel which can be considered as a risk position.

Realistic motion reconstruction is the first step for ‘human like’ motion simulation by a digital human. In a recent European research project REALMAN (IST 2000-29357), a model-based motion reconstruction method from external marker trajectories was developed. It consists of two steps. The first one is to define a digital twin of a real subject using the technique of superimposing a digital human model upon at least two photos of different view, and identifying marker positions on it. In a second step, joint angles are estimated by using a kinematic model of the human body which is described using natural coordinates: coordinates of points and components of unit vectors for defining the joint locations. The model includes a detailed description of the torso, arms and legs, with simplified hands and feet. A total of 26 joints are used, connecting 27 rigid links, among them 6 located on the spine.

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.

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.