Search

The effectiveness of matching the heights of front rails was investigated based on car-to-car crash tests conducted by the Ministry of Land, Infrastructure and Transport in Japan. Two minicar-to-large car crash tests were conducted with different conditions of front rail heights. In the test of the original ride height (where the minicar front rails were lower than the large car), the minicar underrode the large car and the upper location of the minicar structure deformed. In the second test, car ride heights were modified so that the front rail heights for each vehicle were matched. For this case, the front rails of both cars deformed and dummy injury criteria in the minicar were reduced. The height of front rails and their deformations were also examined in car-to-car crash test data. In the tests where the front rails were lower than the other cars, their longitudinal deformations tended to be small but vertical deformations were large. It was shown that matching of the height of front rails was effective for improving the structural energy absorption and for the reduction of the dummy injury criteria. [ABSTRACT FROM AUTHOR]

Bicyclist and pedestrian injuries in collisions with vehicles in Japan were investigated based on national and in-depth accident data analyses and mathematical simulations. In an impact with a bonnet-type vehicle, a bicyclist slides over the bonnet of the vehicle, behavior that is not observed for pedestrians. As a result, the bicyclist’s head tends to strike a bonnet-type vehicle at a more rearward location in comparison with pedestrians. The first contact position of a bicycle with a vehicle, the vehicle front-end geometry and the bicycle velocity affect whether the bicyclist’s head strikes the vehicle or not. Due to the bent-knee posture of a bicyclist’s legs, the types of leg injuries sustained by bicyclists and their causes differ from those seen for pedestrians. Component test procedures have been proposed for evaluating pedestrian safety, but some modifications of the head impact area and angle are necessary when applying these methods to bicyclists. [Copyright &y& Elsevier]

• Understand the kinematic behavior and injury risk of children in collisions. • The effects of seat belts and head restraints of child seats were investigated. • From fall tests, the head restraint reduced the severity of the impact on the head. • The usage of the seat belt changed the kinematic behavior of the child dummy. • From collision tests, head restraints and seat belts reduced the risks of injury. In Japan, traffic accidents involving bicycles have become a serious problem as a result of the increase in the use of bicycles due to the rising concerns of environmental and health problems. In recent years, bicycles equipped with child seats have become a popular means of transportation for preschool children in urban areas in Japan. Under such adverse circumstances, it is necessary to conduct more studies and evaluations to prevent traffic accidents and the resulting injuries involving bicycles with children. For accident prevention and damage mitigation, this study mainly aims to understand the kinematic behavior and injury risk of children in collisions involving bicycles equipped with child seats through experiments. First, fall tests were conducted to evaluate the effect of the integrated head restraints (also commonly known as headrests) of child seats. It was confirmed that head restraints can reduce the impact of head collisions with the road surface. Second, side collision tests were conducted between a car and a bicycle equipped with a child seat, and the effects of the seat belt and head restraint of the child seat were investigated. It was shown that the kinematic behavior of the child dummy significantly was changed depending on wearing the seat belt. In the condition that the seat belt was not fastened, the child dummy was ejected out of the child seat while rotating toward the hood after the impact with the front of the car. In contrast, when the seat belt was fastened, the child dummy was restrained in the child seat and moved together with the bicycle from the start of the collision until the complete stop. Thus, it was found that using child seats with head restraints and using seat belts can reduce the risk of injury to children during an impact with the road surface, because the child dummy in the tests impacted the road surface only after the bicycle already had contact with the road surface. [ABSTRACT FROM AUTHOR]

Pedestrian protection is one of the key topics for safety measures in traffic accidents all over the world. To analyze the relation between the collision site of the vehicle bumper and the severity of the lower extremity injuries, we performed biomechanical experiments. We compared the applied external force and the risks of subsequent injuries between the impact of the center and side positions of the front bumper. These comparisons were performed by practical impact tests with eight typical different types of cars which were typical of the current vehicle fleets. The tests were made using the TRL legform impactor which was a mechanical substitute of a pedestrian lower extremity. The TRL impactor is used all over the world for assessing the safety of car bumpers. It was found that the risks of lower extremity injuries in the impacts at the side positions, in front of the vehicle's side member, were significantly higher than those at the center. In the tests, we found that foam materials around the rigid front cross member had a significant effect on reducing the lower extremity injury risks and especially tibia fracture risk against vehicle bumper center collisions, but had little effect at the sides of the bumper over the vehicle's side members where the foam was thinner. We also found that the front shape of the vehicle affected the risk of ligaments injuries. According to these results, the information of impact locations of cars in vehicle-to-pedestrian traffic accidents is valuable for clinicians to diagnose patients with lower extremity injuries in traffic accidents and for forensic pathologists to analyze the accident reconstruction. Furthermore, the results suggest that testing of the bumper area in front of the main longitudinal beams should be included in the car safety legislation to require pedestrian safety., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Purpose: To clarify the incidence and mechanisms of maxillofacial injuries sustained by motor vehicle passengers, in-depth data from the Institute for Traffic Accident Research and Data Analysis, Japan, were retrospectively analyzed., Materials and Methods: From the Institute for Traffic Accident Research and Data Analysis in-depth data for 1993 through 2005, data were collected for 226 individuals with maxillofacial injuries who were adult passengers involved in frontal motor vehicle collisions. The accident information, a subject's medical data, and anatomic Injury Severity Scores were examined., Results: The median Injury Severity Score was 2, and the mean equivalent barrier speed of the vehicles was 35.2 ± 13.0 km/hour. The most common maxillofacial injuries were lacerations (46.7%), followed by abrasions (41.9%), fractures (14.0%), and dental injuries (5.7%). Maxillofacial fractures occurred more often in unrestrained drivers without airbag deployment (18.4%) and less often in restrained drivers with airbag deployment (4.3%). The incidences of fractures caused by impacts with areas other than the steering wheel were markedly decreased using any safety device (35.5% to 0%)., Conclusion: Combined use of seat belts and airbags by occupants decreases fractures compared with completely unrestrained occupants. Furthermore, wearing a seat belt prevents the free flight of drivers within a vehicle and contact with the interior of a vehicle (other than the steering wheel). Although the anatomic Injury Severity Score of maxillofacial injuries was relatively low, because these injuries are also associated with socioeconomic costs, the correct use of safety devices and further development of more effective injury prevention systems are needed., (Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)