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Improvement of pedestrian safety is considered a priority in crash injury protection. Dummies, however, are not able to give a humanlike and repeatable impact response in pedestrian tests. The Biomechanical Laboratory of ONSER in France and the Department of Traffic Safety of Chalmers University in Götheborg, Sweden have designed a new dummy for pedestrian testing. The dummy is designed according to the latest available anthropometric and biomechanical data. Its symmetry around the vertical axis allows repeatability for the kinematic and injury parameters. It allows a measurement of uncommon biomechanical parameters related to injury mechanisms. Its leg is instrumented to determine the distribution of forces and momenta applied to the leg.

Since numerous years, the vehicle industry is interested in occupant safety. The dummy use in crash tests allowed to create protective means like the belt and the airbag that diminished the injuries of the head and the thorax, which are often lethal for the car occupant. An other objective appears now: to improve the car safety to avoid the injuries which are not fatal but which can cause disability and which cause great cost in hospitalization and rehabilitation. The lower extremity protection, in particular the one of the ankle and the foot region, has become the subject of diverse research efforts by its high percentage of injuries in car crashes. But the dummy mechanics cannot reproduce the accurate ankle and the foot kinematics during an impact loading like in vehicle crash. Therefore, ankle/foot complex numerical models are an essential tool for the car safety improvement.

Over the past few years, we made use, almost systematically, of transducers in order to detect submarining. We nave acquired a certain knowledge of submarining process and we have thought that it was necessary to take stock of this phenomenon. Different types of submarining transducers are reviewed in this paper. We will see that these techniques need still improvements and they are open to criticism. In fact, it can be considerated that submarining detection is not entirely resolved and it is a subject which raises some important questions.

Injuries to the thorax in frontal impact accidents remain an important problem even for restrained occupants. During a frontal accident a significant portion of the forces restraining the occupant pass through the thoracic belt and deform the chest with the possibility of serious thoracic injuries. It is therefore important to understand the deformation of the human thorax when loaded by a thoracic belt and to understand how accurately crash dummies used in standard tests reproduce these deformations. This paper describes results of 19 tests in which a diagonal shoulder belt dynamically loaded the thorax of unembalmed cadavers and dummies (1). In all the tests, thoracic external deformations were measured using string potentiometers and two External Peripheral Instrument for Deformation Measurement (EPIDM) transducers (2).

Pelvic fracture is a typical lesion sustained by the occupant of a vehicle involved in a lateral impact collision who is seated on the impact side. If this fracture is generally not severe by itself, it is nevertheless often associated with severe abdominal lesions. Study of injury mechanisms in lateral impact collisions shows that there are two ways of ensuring a better protection of the occupant in this type of accident: first by preventing intrusion so that the contact velocity “occupant/inner door” is decreased, secondly by absorbing the shock of the occupant against the inner door, especially at pelvis and thorax levels. It is necessary to have a good knowledge of human tolerance to fracture of the considered body segment in order to determine the mechanical properties of the padding material. The aim of this study is to determine the tolerance of the human pelvis.

Since many years, the vehicle industry is interested in occupant safety. The dummy use in crash tests allowed to create protective means like the belt and the airbag that diminished the injuries of the head and the thorax, which are often lethal for the car occupant. An other objective appears now: to improve the car safety to avoid the injuries which are not fatal but which can cause disability and which cause great cost in hospitalization and rehabilitation. The lower extremity protection, in particular the one of the ankle and the foot region, has become the subject of diverse research efforts by its high percentage of injuries in car crashes. But the dummy mechanics cannot reproduce the accurate ankle and the foot kinematics during an impact loading like in vehicle crash. Therefore, ankle/foot complex numerical models are an essential tool for the car safety improvement.

The thorax is frequently involved in side impact accidents; in such accidents, injuries to the thorax are related to the intrusion. The position of the impacted side arm can affect the occuring of thoracic injuries in side impact. This study describes the results of 15 side impact thoracic tests performed on 8 cadavers; most of these tests are conducted with arm involvement (the upper arm is places along the thorax and the impact is transmitted to the thorax through the arm). The results of these tests are compared to the results of 6 tests previously published, conducted without arm involvement (the impact was applied directly to the thorax). From these results, it appears that the arm offers a limited protection when it is placed along the thorax, by distributing impact forces on the chest, and that the BLUR criterion is not well correlated with the thoracic injuries severity.

INRETS has performed in its Crash and Biomechanics Research Laboratory (LCB) series of frontal impact barrier tests with modern passenger cars in different test conditions. Three tests are made with each selected models: On the cars decelerations are recorded in different points for crashworthiness analysis. Two fully instrumented Part 572 dummies are installed in the front seats and are restrained using the vehicles belts. It is proposed to correlate the values of protection criteria with the parameters defining the test conditions and those characterizing the car behaviour during the crash test.

The protection of car occupants against side impact accidents needs a better knowledge of injury mechanisms and of tolerance which are necessary to propose protection criteria. The results of the study reported in this paper give the values of pelvic fracture impact force and indicate the variation of this parameter in relation to the anthropometric parameter. The injuries produced by these tests were compared to pelvic injuries sustained in side impact real accidents; static tests made with half a pelvis have shown that the pubic rami were the deformed part of the pelvis. According to these findings, we have tried to correlate the impact force values and the values of a parameter linked with the bending process. This relationship have been found very well correlated. These results allow to propose a pelvic human tolerance parameter from which a protection criterion for pelvis in side impact could be derivated.

This paper provides an overview of the progress and of the research projects of the French Government in the area of road vehicle safety. It presents the main topics covered by the French national research program for research and development in land transports, shows the importance of international cooperation in safety research and proposes further issues to improve vehicle safety.