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The advanced Pedestrian Legform Impactor (aPLI) incorporates a number of enhancements for improved lower limb injury prediction capability with respect to its predecessor, the FlexPLI. The aPLI also incorporates a simplified upper body part (SUBP), connected to the lower limb via a mechanical hip joint, that expands the impactor’s applicability to evaluate pedestrian’s lower limb injury risk also in high-bumper cars.As the aPLI has been developed to be used in standardized testing, further considerations on the impactor’s manufacturability, robustness, durability, usability, and repeatability need to be accounted for.. The aim of this study is to define and verify, by means of numerical analysis, a battery of design modifications that may simplify the manufacturing and use of physical aPLIs, without reducing the impactors’ biofidelity. Eight candidate parameters were investigated in a two-step numerical analysis.

ISO 26262, an international functional safety standard of electrical and/or electronic systems (E/E systems) for motor vehicles, was published in November 2011 and it is expected that the scope will be extended to motorcycles in a second edition of ISO 26262 going to be published in 2018. ISO/DIS 26262 second edition published in 2016 has Part 12 as a new part in order to apply ISO 26262 to motorcycle. Proper estimation of Exposure, Controllability, and Severity in accordance with ISO/DIS 26262 Part 12, are key factors to determine Motorcycle Safety Integrity Level. To estimate precise these factors, there would be a case that it might not be appropriate to apply studies done for passenger car to motorcycle, and it would be necessary to apply motorcycle specific knowledge and estimation methods. In our previous studies we clarified these motorcycle specific issues and studied the method for the adaptation.

ISO 26262, an international functional safety standard of electrical and/or electronic systems (E/E systems) for motor vehicles, was published in November 2011 and it is expected that the scope will be extended to motorcycles in a second edition of ISO 26262 going to be published in 2018. In order to apply ISO 26262 to motorcycle, proper estimation of Exposure, Controllability, and Severity are key factors to determine Motorcycle Safety Integrity Level (MSIL). Exposure is a factor to indicate the probability of the state of an operational situation that can be hazardous with the E/E system malfunction. And it is not easy to estimate the motorcycle Exposure due to less availability of back ground data in actual operational situation compared to motor vehicle. Therefore real traffic situation should be investigated in order to provide rationales for MSIL determination.

Current legform impact test methods using the FlexPLI have been developed to protect pedestrians from lower limb injuries in collisions with low-bumper vehicles. For this type of vehicles, the influence of the upper body on the bending load generated in the lower limb is compensated by setting the impact height of the FlexPLI 50 mm above that of pedestrians. However, neither the effectiveness of the compensation method of the FlexPLI nor the influence of the upper body on the bending load generated in the lower limb of a pedestrian has been clarified with high-bumper vehicles. In this study, therefore, two computer simulation analyses were conducted in order to analyze: (1) The influence of the upper body on the bending load generated in the lower limb of a pedestrian when impacted by high-bumper vehicles and (2) The effectiveness of the compensation method for the lack of the upper body by increasing impact height of the FlexPLI for high-bumper vehicles.

ISO 12405-1,2 specifies international testing standards for lithium-ion batteries for vehicles. In the mechanical shock test is used to determine if the battery is damaged due to the shock imposed when the vehicle runs over a curb or similar minor accidents. Therefore, we conducted minor collision tests against a curb using an actual vehicle and compared the test results with the conditions specified in ISO 12405-1,2. The results confirmed that the impulse wave obtained using an actual vehicle within the range of the test in this study differs from the shape of the impulse wave specified in ISO 12405-1,2.

The objective of the current study was to provide a comprehensive characterization of human biomechanical response to whole-body, lateral impact. Three approximately 50th-percentile adult male PMHS were subjected to right-side pure lateral impacts at 4.3 ± 0.1 m/s using a rigid wall mounted to a rail-mounted sled. Each subject was positioned on a rigid seat and held stationary by a system of tethers until immediately prior to being impacted by the moving wall with 100 mm pelvic offset. Displacement data were obtained using an optoelectronic stereophotogrammetric system that was used to track the 3D motions of the impacting wall sled; seat sled, and reflective targets secured to the head, spine, extremities, ribcage, and shoulder complex of each subject. Kinematic data were also recorded using 3-axis accelerometer cubes secured to the head, pelvis, and spine at the levels of T1, T6, T11, and L3. Chest deformation in the transverse plane was recorded using a single chestband.

The SAE Fuel Cell Vehicle (FCV) Safety Working Group has been addressing FCV safety for over 9 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable as a Recommended Practice for FCV development with regard to the identification of hazards and the definition of countermeasures to mitigate these hazards such that FCVs can be operated in the same manner as conventional gasoline internal combustion engine (ICE)-powered vehicles. SAE J2578 is currently being revised so that it will continue to be relevant as FCV development moves forward. For example, test methods were refined to verify the acceptability of hydrogen discharges when parking in residential garages and commercial structures and after crash tests prescribed by government regulation, and electrical requirements were updated to reflect the complexities of modern electrical circuits which interconnect both AC and DC circuits to improve efficiency and reduce cost.

A total of eight low-speed, rear-end impact tests using two Post Mortem Human Subjects (PMHS) in a seated posture are reported. These tests were conducted using a HYGE-style mini-sled. Two test conditions were employed: 8 kph without a headrestraint or 16 kph with a headrestraint. Upper-body kinematics were captured for each test using a combination of transducers and high-speed video. A 3-2-2-2-accelerometer package was used to measure the generalized 3D kinematics of both the head and pelvis. An angular rate sensor and two single-axis linear accelerometers were used to measure angular speed, angular acceleration, and linear acceleration of T1 in the sagittal plane. Two high-speed video cameras were used to track targets rigidly attached to the head, T1, and pelvis. The cervical spine kinematics were captured with a high-speed, biplane x-ray system by tracking radiopaque markers implanted into each cervical vertebra.

Test procedures to assess vehicle compatibility were investigated based on a series of crash tests. Structural interaction and compartment strength are significant for compatibility, and full-width tests and overload tests have been proposed to assess these key factors. Full-width rigid and deformable barrier test results were compared with respect to force distributions, structural deformation and dummy responses. In full-width deformable tests, forces from structures can be clearly shown in barrier force distributions. The average height of force (AHOF) determined in full rigid and deformable barrier tests were similar. From car-to-car tests, it was demonstrated that stiffening the compartment of small cars is an effective and direct way to improve compatibility. To evaluate the compartment strength, five overload tests were carried out. The rebound force is proposed as a compartment strength criterion.

JAMA-JARI has developed a biofidelic flexible pedestrian leg-form impactor (Flex-PLI 2004) by making several modifications to the Flex-PLI 2003 to improve usability, durability and biofidelity. Biofidelity evaluation for the Flex-PLI 2004 was estimated at the component level (thigh, knee, and leg individually) as well as at the assembly level (thigh-knee-leg complex), using an objective impactor biofidelity evaluation system based on a method developed by Rhule et al. to eliminate any subjective prejudice in an impactor biofidelity evaluation. Applying the biofidelity evaluation system to the Flex-PLI 2004, the average impactor biofidelity rank (IBR) score became 1.22 at the component level and 1.26 at the assembly level. These IBR scores mean that the Flex-PLI 2004 has good biofidelity at the component level as well as at the assembly level.

Frontal vehicle collisions often result in foot injury of the front seat occupant. Therefore, it is very important to understand the mechanism of the foot injury. For that purpose, several impact experiments have been conducted using a partial human lower extremity. In addition, recently several impact response analyses using a human FE model have been conducted to understand the mechanism. In the present circumstances, a verified FE model is needed, and the verification of kinematical biofidelity is very important in the first place. In this connection, a foot FE model (based on an existing human FE model) was improved to create a foot FE model, which can be used for study of foot injury mechanism in this research. And the kinematics of foot bones of the model was verified by comparing the bone movements of the FE model with the movement of human foot during heel impact.

A biofidelic flexible pedestrian leg-form impactor, called Flex-PLI, was developed by the Japan Automobile Manufactures Association, Inc. (JAMA) and the Japan Automobile Research Institute (JARI). Its latest version is called Flex-PLI 2003. The Flex-PLI 2003 responses have been validated at the component level (thigh, leg, and knee independently) but not at the assembly level (thigh-knee-leg complex). Furthermore, there was no FE Flex-PLI model. This research developed a FE Flex-PLI 2003R model (Flex-PLI 2003R means that the thigh and leg mass of Flex-PLI 2003 is adjusted to AM 50). The FE Flex-PLI 2003R model biofidelity has been evaluated at both the component level and the assembly level, where it demonstrated high biofidelity.

The main objective of the present study is to determine experimentally the injury patterns and response of the human thigh in lateral impacts simulating more closely the real impact conditions in car-pedestrian accidents. We conducted in-vitro experiments on thirteen thighs of eight completely intact Post Mortem Human Subjects (PMHSs). The thigh was hit by a ram at a speed of 35 km/h at the mid-shaft of the femur in each completely intact PMHS. Since the effect of cumulative injuries should be avoided, each thigh was impacted only once. Three impact energies were used; 450J, 600J and 700J. The PMHS motion was not constrained so as to simulate the walking posture of a pedestrian. We analyzed the peak values of the impact force of the ram and the femur acceleration. Injury was assessed by dissecting the lower extremities.

The European Enhanced Vehicle-Safety Committee (EEVC) has proposed a test procedure to assess the protection vehicles provide to the lower extremity of pedestrians during a collision. This procedure utilizes a legform impactor developed by the Transport Research Laboratory (TRL). However, the TRL Pedestrian Legform Impactor (TRL-PLI) is composed of rigid long bones (cannot simulate the bone flexibility of the human) and rather stiff knee joint. The differences lead to a lack of biofidelity of the TRL-PLI, i.e., unnaturally stiff responses are observed. This study develops a biofidelic Flexible Pedestrian Legform Impactor (Flex-PLI) that can simulate human bone flexibility and human knee joint stiffness properly. The Flex-PLI can also measure many of the injury parameters, long bone strains at multiple locations, knee ligament elongations, and the compression forces between the femoral condyles and tibial plateau in comparison to the TRL-PLI.

Numerous studies of pelvic tolerance to lateral impact aimed at protecting car occupants have been conducted on Post Mortem Human Subjects (PMHSs) in a sitting posture. However, it remains unclear whether or not the results of these studies are relevant when evaluating the injury risk to walking pedestrians impacted by a car. Therefore, the first objective of the present study is to determine the injury tolerance and to describe the injury mechanisms of the human pelvis in lateral impacts simulating car-pedestrian accidents. The second objective is to obtain data for validation of mathematical models of the pelvis. In-vitro experiments were conducted on twelve PMHSs in simulated standing position. The trochanter of each PMHS was hit by a ram at speed of 32 km/h, and the pelvic motion was constrained by a bolt. This type of pelvic constraint is difficult to simulate in mathematical models.

The strength of the passenger compartment is crucial for occupant safety in severe car-to-car frontal offset collisions. Car-to-car crash tests including minicars were carried out, and a low end of crash force was observed in a final stage of impact for cars with large intrusion into the passenger compartment. From overload tests, the strength could be evaluated from collapsing the passenger compartment. Based on the test, the end of crash force as well as the maximum forces might be important criteria to determine the passenger compartment strength, which in turn could predict the large intrusion into the passenger compartment in car-to-car crashes. A 64 km/h ODB test was insufficient to evaluate the potential strength of the passenger compartment because the maximum forces could not be determined in this test.

Single cylinder engine testing was carried out to clearly understand the test results of multi-cylinder engines reported by the Diesel WG in JCAP (Japan Clean Air Program) (1), (2), (3) and (4). In this tests, engine specifications such as fuel injection pressure, nozzle hole diameter, turbo-charging pressure, EGR rate, and fuel properties such as 1-, 2-, 3-ring aromatics content, n-,i-paraffins content, and T90 were parametrically changed and their influence on the emissions were studied. PM emission generally increased in each engine condition with increased aromatic contents and T90. In particular, multi ring aromatics brought about large increases in PM regardless of the engine conditions. The influence of fuel properties on NOx emission is smaller than the influence on PM emission. Some other fuels that have various side chain structures of 1-ring aromatics, normal paraffins only and various naphthene contents were also investigated.

Evaluation of car front aggressiveness in car-pedestrian accidents is typically done using sub-system tests. Three such tests have been proposed by EEVC/WG17: 1) the legform to bumper test, 2) the upper legform to bonnet leading edge test, and 3) the headform to bonnet top test. These tests were developed to evaluate performance of the car structure at car to pedestrian impact speed of 11.1 m/s (40 km/h), and each of them has its own impactor, impact conditions and injury criteria. However, it has not been determined yet to what extent the EEVC sub-system tests represent real-world pedestrian accidents. Therefore, there are two objectives of this study. First, 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-to-pedestrian accidents. Second, to propose modifications of current sub-system test methods. In the present study, the Polar (Honda R&D) dummy was used.

The goal of the present study was to develop a new legform impactor that accurately represents both the impact force (i.e., force between the leg and impacting mass)and leg kinematics in lateral impacts simulating car-pedestrian accidents. In its development we utilized the knee joint of the pedestrian dummy called Polar-2 (HONDA R&D) in which the cruciate and collateral ligaments are represented by means of springs and cables, the geometry of the femoral condyles is simplified using ellipsoidal surfaces, and the tibial meniscus is represented by an elastomeric pad. The impactor was evaluated by comparing its responses with published experimental results obtained using postmortem human subjects (PMHS). The evaluation was done under two conditions: 1)impact point near the ankle area (bending tests),and 2)impact point 84 mm below the knee joint center (shearing tests). Two impact speeds were used: 5.56 m/s and 11.11 m/s.

The New Car Assessment Program in Japan (JNCAP) was launched in 1995 in order to improve car safety performance. According to this program, installation conditions of safety devices and the results for braking performance and full- frontal crash tests are published every year. Introduction of JNCAP significantly increases the installation rate of safety devices and contributes much in enhancement of safety as seen in the decrease in the average injury severity of drivers and passengers. Side impact and offset frontal crash tests were introduced in 1999 and 2000, respectively. At present, the overall crash safety rating is carried out based on the results of the full-frontal, offset frontal, and side impact tests.