Search Results

ESP (Electronic Stability Programme) systems enable the stability of a car to be maintained during critical manoeuvres and to correct potential understeering or oversteering. As a result, ESP could help improve car safety by avoiding loss of vehicle control accidents as well as by reducing their severity or consequences. This paper describes an evaluation of the potential effectiveness of ESP if it was installed more widely. It is based on data from the European Accident Causation Survey (or “EACS”) which contains information about 1,674 accidents in 5 European countries. Analysis of the EACS data shows that in approximately 18% of all injury accidents and in 34% of fatal accidents, ESP would have a certain influence (either reducing the likelihood of an accident or avoiding the accident altogether). Where accident causation was identified as “loss of vehicle control”, ESP would have a certain benefit in 42% of cases with injury outcome and in 67% of the fatal crashes.

The analysis of accidents studied by LAB shows that, among injured belted drivers involved in frontal crashes, in cars without airbags, head injury risk is the highest along with lower limbs ‘s one. The LAB investigation of severe accidents, involving new car models, regularly carried out all over the French territory, has given the opportunity to analyse head injury risks for about 300 belted drivers in crashes with airbags. The average severity of these accidents was in the range of EuroNCAP tests. (between 36 and 65 km/h EES) The present paper’s purpose is to compare the risk of head injury for belted drivers with and without airbag. Other body area injury risk, like neck and upper limbs, has also been considered. These severe accidents analysis shows high airbag efficiency in reducing severe facial and brain injuries.

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.

Computational techniques are being used more and more in automotive safety engineering. However there is still a need for further development of biofidelic tools for assessing human responses in crash situations. We therefore designed a 3D finite element model of the human body and constituted a large experimental database for the purpose of validation. The geometry of the seated 50th percentile adult male was chosen for the model. The number of elements used to represent the anatomy was limited to 10 000. The material laws come from existing literature and, when necessary, parameter identification processes were used. Special attention was paid to the constitution of the validation database. Boundary conditions and results from most of the available cadaver and volunteer experiments were analyzed. In total, more than 30 test configurations were selected.

The present study describes the development of a refined finite element model of the human pelvis. The objectives of this research work were to: Statistically study the human pelvis geometry, and develop a parameterized model. Mechanically validate the model with regard to the available in-house experimental data. Model the injury mechanisms observed in the experimental studies. The significant dimensions of the pelvis were identified by statistical analysis of the pelvis geometry based on the Reynolds et al. data [1]. Those dimensions were used to classify the in-house tested pelves. An interpolation technique (Kriging [2, 3, 4, 5, 6, 7 and 8]) was then used in order to distort a reference mesh and adapt its geometry to the measured geometry of the tested pelvis. The mechanical validation of the model was carried out by comparing numerical and experimental results, and the influence of the geometrical variations on the behavior of the pelvis was thus assessed.

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.