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To estimate the behaviour of the thorax of the human cadaver and Hybrid III a total of 33 belt impact tests were performed with the two surrogates. These tests have shown that the Hybrid III thorax is stiffer than that of the cadaver and that the internal thoracic deflection transducer may not necessarily record the maximum thoracic deflection. The belt load was lower value with the cadavers, which confirms the differences in stiffness. A belt force of 10 KN in the cadaver tests was associated with an average of 6 rib fractures. If we consider the relationship between the thoracic deflection and the number of rib fracture cadavers showing 5 or more rib fractures sustained an external thoracic deflection at least of 7.5 cm measured at the mid sternum. The analysis of V*C parameter indicates an average V*C value of 0.77 for 6 rib fractures, and the values of V*C measured on Hybrid III are sligthly lower than those of cadaver tests.

The WorldSID is a new, advanced Worldwide Side Impact Dummy that has the anthropometry of a mid-sized adult male. It has a mass of 77.3 kg, a standing height of 1753 mm and a seated height of 911 mm. Almost every body region is a new, innovative design, setting the WorldSID apart from all existing side impact dummies. It incorporates over 200 available data channels, in-dummy wiring, and an in-dummy data acquisition system (DAS). The dummy is designed to be used for research and future harmonized side impact test procedures as defined by the International Harmonized Research Activities (IHRA) and other organizations. It is expected to have a biofidelity classification of “good” to “excellent” using the International Organization for Standardization (ISO) dummy classification scale. The WorldSID will be the basis for the future development of a side impact dummy family.

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.

Improvements for pedestrian head protection in a car-pedestrian accident have been discussed in several countries. Test methods for evaluating head protection have been proposed, and most are sub-systems using rigid headforms with or without headskin. In those tests, HIC is used as a criterion for head protection. This paper discusses the test conditions and requirements of the headform impact test. The influence of different test conditions and their importance on head impact test requirements, were verified. The primary items cited are as follows: (1) The results of the rigid headform were similar to that of the human cadaver skull in cases without skull fractures. Consequently, the rigid headform can be used for the impactor simulating a condition without skull fracture. (2) In the cases of HIC≤1000, the force-deformation curves of the hoodtops showed similar characteristics with maximum dynamic deformations over 60mm. (3) Impactor mass affected the maximum acceleration and HIC.

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).

This paper contains the results of 50% offset frontal collision tests which were conducted in order to analyze impact situation of ankle/foot regions during car-to-car crashes with both 50km/h running speeds. We took high-speed films of the footwell regions, and measured impact forces of Hybrid-III lower legs, three-axis accelerations of the toe-board, floor and brake pedal in the tests. In the same collision configuration, we conducted the tests under four different test conditions of driver seating situations as follows: with seatbelts + stepping on the brake pedal, with seatbelts + stepping on the accelerator pedal, without seatbelts + stepping on the brake pedal, and without seatbelts + stepping on the accelerator pedal. In this paper, we focused on motions and impact forces of lower legs, on intrusions and movements of the floor, toe-board and pedals, and on interactions with them during crashes.

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.

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.

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.

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.

Eight barrier to car side impact tests were conducted with dummies and with cadavers. The barrier and the test configuration were those proposed by NHTSA for side impact car testing. Two types of car were used: an unmodified (baseline) Rabbit, and a modified (for side impact protection) Rabbit. The modifications concern the reinforcement of the side structures and the use of an internal padding for protection of pelvis and thorax. The results of these tests show a good repeatability of car deformation, a decrease of injury related parameters with the modified Rabbit, and a change in the velocity of car elements and body regions.

In order to establish a systematic approach to the study on the injuries sustained by motorcycle riders in accidents and the assessment of protective devices fitted to motorcycles, this research develops a computer simulation model of motorcycle-to-vehicle collision model based on multibody kinematics and dynamics using MADYMO (MAthematical DYnamic MOdel). The effectiveness of the motorcycle-to-vehicle crash model is verified using data of 14 full-scale tests. Comparisons between the simulation peak head acceleration results and the full-scale crash tests data demonstrate a satisfactory agreement between them. The simulation results along with the test data indicate that the leg protectors fitted to the motorcycle can induce harmful consequences to the rider head in some configurations, regardless of their aimed protective effects on the rider’s legs. The findings obtained in this study also provide basis for further improvement of the current model.

The results of biomechanical testing of the WorldSID prototype dummy are presented in this paper. The WorldSID dummy is a new, advanced Worldwide Side Impact Dummy that has the anthropometry of a mid-sized adult male. The first prototype of this dummy has been evaluated by the WorldSID Task Group against previously established corridors for its critical body regions. The response corridors are defined in the International Organization of Standardization (ISO) Technical Report 9790. The prototype is the first version of the WorldSID dummy to be built and tested. This dummy has been subjected to a rigorous program of testing to evaluate, first and foremost its biofidelity, but also its repeatability. Following this initial evaluation, any required modifications will be incorporated into a pre-production version of the WorldSID dummy so that it rates “good” to “excellent” on the ISO dummy biofidelity scale – a rating exceeding that of all current side impact dummies.