Yasuhiro Matsui

Comparison of pedestrian subsystem safety tests using impactors and full-scale dummy tests

The study had two objectives: to clarify the differences between the injury related responses of full scale pedestrian dummy and results of sub-system tests obtained under impact conditions simulating car-pedestrian accidents; and to propose modifications of current sub-systems test methods. The study results demonstrate, using compact car and sport utility vehicles, that the headform and upper legform test procedures may overestimate severity of impact between car front and pedestrian head and pelvis, especially for SUVs. Additionally, the current legform impactor may not be suitable for evaluation of the aggressiveness of a high bumper car front.

Improvement of accelerometers for pedestrian headform impactors in testing following Japanese vehicle safety regulations

Most pedestrian deaths in car–pedestrian accidents are due to head injuries. In 2005, the Japanese Ministry of Land, Infrastructure, Transport and Tourism (J–MLIT) began assessing the safety of bonnets impacting on pedestrians heads using headform impactors with designated technical specifications. J–MLIT has used Type Approval Regulation Version 1 of headform impactors fitted with small un–damped accelerometers since 2005. Meanwhile, oil–damped accelerometers have been used by J–MLIT Type Approval Regulation Version 2 headform impactors since 2010. This paper summarises the development of pedestrian headform impactors used in headform impact tests in Japan and points to increasing safety levels.

Pedestrian kinematics due to impacts by various passenger cars using full-scale dummy

Experiments were performed in which a Polar (Honda RD the EEVC/WG17 upper legform test procedure seems to overestimate the energy of the impact between the pedestrian waist and SUV front, whereas it appropriately simulates the energy of impact between the pedestrian thigh and front of a medium-size sedan and compact car; and the EEVC/WG17 headform test procedure may overestimate the severity of impact between the car front and the pedestrians head.

Occupant responses in child restraint systems in side impact tests

Accident data show that the injury risks to children seated in Child Restraint Systems (CRSs) are higher in side collisions than any other type. To investigate this, it is necessary to understand the occupant responses in various CRSs. While a sled test procedure has been discussed by the International Organisation for Standardisation for evaluating CRS performance, for which full car side impact tests were conducted with a Q3s child dummy seated in a Forward-Facing (FF) CRS, and a CRABI Six-Month-Old (6MO) infant dummy seated in a Rear-Facing (RF) CRS and also placed in car-bed restraint. In FF and RF CRS tests, the chest was loaded by an intruding door and the resulting chest deflection of the Q3s child dummy in the FF CRS was comparable with the Injury Assessment Reference Value (IARV). In tests with the FF and RF CRSs, the dummy heads were contained within the CRS shell during the entire impact event; and the HICs were small. Although all injury criteria of the CRABI 6MO infant dummy in the car-bed restraint were smaller than the IARVs, a calculated crotch harness force was large.

Pedestrian leg protection performance in current vehicle design in an event of vehicle-to-pedestrian accident

Accident data show that leg injuries are the most common injuries in non-fatal pedestrian traffic accidents. The investigation reported in this article focuses on evaluating the pedestrian protection provided by the front bumpers of three different types of current Japanese vehicle: sedan, sport utility vehicle and K-car (engine displacement of 660 cc or less). The investigation used the Transport Research Laboratory (TRL) legform impactor. The protection performance related to knee ligament injury and tibia fracture greatly depended on the vehicles frontal shape and the stiffness of both the bumper and the bonnet or grill of the vehicle. The study showed that for the three vehicles tested, the pedestrian leg protection performance at the bumper centre location was excellent but the performance of the bumper in front of the longitudinal members was poor.

818 TRL脚部インパクタおよびフレキシブル脚部インパクタの実車衝突試験における特性(S02-4 インパクトバイオメカニクス(4) 転倒および下肢傷害,21世紀地球環境革命の機械工学:人・マイクロナノ・エネルギー・環境)

Pedestrian protection is one of the key topics of discussion in the area of vehicle safety legislation in Europe and Japan. Leg injuries are the most common injuries found in non-fatal pedestrian accidents. The EC regulation and Euro NCAP are evaluating pedestrian leg protection performance in current vehicles. The TRL legform impactor is specified by the EC regulation, where Phase 1 took effect during 2005 and a draft phase 2 is scheduled to take effect in 2013. The global technical regulation (GTR) pedestrian protection test protocol was made basically using the TRL legform impactor. However, a flexible legform impactor has been under development. When the flexible legform impactor development is fully completed and evaluated, it is possible that both legform impactors may be determined to be useful in the GTR. Thus, the objective of this study is to investigate the characteristics of pedestrian leg protection performance of the frontal area of current vehicles using the TRL legform impactor and the flexible legform impactor. Different types of vehicles (sedan, sport utility vehicle (SUV), height wagon, and 1 box car) were used. The center of the bumper and center of the side members (i.e., the vehicles main longitudinal beams) were selected as impact locations for the legform impactors tests. This paper discusses an equivalence of injury assessment between the TRL legform impactor and flexible legform impactor. The full text of this paper may be found at: http://www-nrd.nhtsa.dot.gov/pdf/esv/esv21/09-0206.pdf For the covering abstract see ITRD E145407.