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A theoretical study was conducted to prove that the Part 572 dummy submarines more easily than human cadavers because of their different pelvic shapes. The three-dimensional geometrical definition of the lap-belt was developed in this paper for the study of the submarining problem. It was found that not only the lap-belt angles from side view (β1) but also from the upper view in respect to the X-axis (β2) play a significant role in the submarining tendency for each side. The anti-submarining scale is defined by a coefficient which is a function of both angles β1, β2 and the orientation of the upper half of the pelvic notch. A series of sled tests was performed on human cadavers, the Part 572 dummy and the modified dummy. Good agreement was found between the present theory and the experimental results.

Current comparisons between active and passive restraint systems are still subjective and emotional. Statistical data, accident surveys, theoretical studies, and crash test results allow a technical analysis. Taking into account technological problems related to various devices and considering their economical incidence and their efficiency, it is possible to form an objective opinion. Conclusion is that the different principles of restraints are not opposed, but appear as successive steps of a same evolution.

A large number of experiments involving cadavers - including real-world-accident reconstructions - have been performed for the purpose of enhancing the state of knowledge concerning tolerance levels and protection criteria relevant to side-impact conditions. However, the scatter of the findings, as well as the considerable differences in injury severity levels (differences that cannot be accounted for by age differences alone) have limited the conclusions that it was possible to draw from these investigations in terms of criteria, mainly concerning thoracic protection. The major cause of scatter is the considerable differences in skeleton quality between subjects. Analysis of the rib characterization test findings made it possible to define a thoracic resistance index enabling the establishment of a classification of subjects. This index, which was validated with our sample, allowed us to evaluate the pertinence of the various side-impact protection criteria considered.

Experimental simulations of car pedestrian collisions were conducted with production cars impacting a pedestrian dummy derived from PART 572 ; the tests were performed under well standardized conditions to try to limit experimental dispersions. The results corresponding to one series of tests are presented. The comparison of kinematical behaviour of this dummy and human subjects impacted by an other way under identical realistic test conditions displayed differences in kinematics and response at impact between these two kinds of surrogates. These differences can be explained largely by the greater stiffness of the PART 572 dummy, as compared to human subjects. For this reason, it was determined to duplicate the tests performed with the PART 572 dummy with a new series of tests with one APROD dummy, modified in a pedestrian version.

PRAKIMOD has until now been mostly used for simulating pedestrian accidents. It is also a very convenient tool for studying frontal crashes, especially for determining the values of data that are not easily accessible from direct measurements. After a short description of the model and of the belt system, three examples of application are shown. The first one concerns the distribution of energy transfers from a dummy restrained by a shoulder belt and a knee bolster to the different parts of its environment and to the frontal structure of a car. The second one is an attempt to evaluate the respective influences of some parameters (such as the joint stiffnesses or mass distributions among the body parts) on the dummy's propensity for submarining. The third one concerns the problem of separating the effects of neck forces on the one hand, and of a direct impact on the steering wheel on the other hand.

This paper deals with frontal crash simulations with 3 point seat-belts, in which the conventional anthropomorphic test dummy has been replaced by a fresh unembalmed cadaver. Numerous test conditions have been used. Here are the complete results on the thorax for 31 cadavers in dynamic tests and 7 others in static tests. Specific interest in the thorax comes from the examination of injuries which has shown that, for a normal test, severe injuries are seldom located elsewhere than in the thorax. Methodology, which is the first described, states in particular how the cadavers are prepared with reconstitution of blood pressure and lung inflation and how skeleton strength is characterized. Among the results shown are those for the thorax autopsies, the corresponding seat belt restraint forces, some measurements with dummies used simultaneously and some data on recorded thorax deflections.

Car-pedestrian accidents were selected with reference to criteria like relevance in terms of injury severities representativity and reproducibility aiming to as accurate as possible reconstructions by dummy and cadaver tests. Parameters necessary for performance of these reconstructions were evaluated from the data of accident investigation teams. Preliminary tests were performed by research departments of automobile manufacturers to check the estimated conditions of these accidents before performing their reconstructions. A particular aim was to obtain insights into the mechanisms leading to injuries in pedestrian accidents; more generally reconstructing actual accidents is a privilegied approach to determine human tolerance limits and the corresponding protection criteria on dummies; the injuries resulting from the actual accidents are consequently compared with the data measured on dummies and cadavers in the reconstruction experiments.

This study is related to the modifications of Part 572 dummy for lateral impact, to aid in the evaluation of the injury reducing potential of automotive lateral protection systems. This was done by modifying the rib cage, arms and shoulders of Part 572 so that its impact performance more closely simulates that of a human. According to biomechanical data coming from cadaver testing, the arm was modified by reducing the size of the structural members and increasing the padding of the arm; the mobility of the shoulder was increased in both forward and upward directions. Moreover, the shoulder was modified to become transversely collapsible to a certain extent. The rib cage was redesigned so as to give a more realistic deformation. The measurement of lateral chest deflection was also incorporated into the rib cage design. The frontal impact characteristics of the dummy, both for impact and belts, were left unchanged.

Anthropometric data relative to the pelvis have been obtained from X-rays of volunteers and Part 572 dummy, as well as pelvic bones of 28 human skeletons. Consequently, modifications in the pelvic portion of Part 572 dummy are proposed. These are based on the study in the difference of tendancy to submarining, the difference of the pelvic shape, and the abdominal flexibility between Part 572 dummy and the human being.