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The non-physiological motions of human cervical vertebrae were analyzed in volunteer tests for rear-end impacts and were considered to be an important parameter for neck injuries. The objectives of this study are to improve the Marko de Jager neck model using volunteer test data and to analyze the influence of horizontal and vertical accelerations on cervical vertebral motion. In the beginning of this study, a neck model was positioned based on X-ray cineradiography of a volunteer. Motions of each vertebra were compared with those of volunteer test data for low speed rear-end impacts (4, 6, 8km/h). In these comparisons, the differences of vertebrae motions between the neck model and the volunteer tests were found. To improve the validity of the neck model, the connection properties and the bending properties of the upper and lower vertebrae of the model were modified to increase rigidity.

Researchers concerned with motorcycle occupant protection have attempted to develop ways to protect the motorcycle occupant from injury. In the hope of finding a means to protect the motorcycle occupant's lower extremities, the authors have investigated past research, designed a device that incorporates an energy-absorbing component, tested the device in a series of collisions with automobiles, and performed an analysis of the test results to assess the merits of the new device. Results show that although the device may under certain circumstances reduce lower leg injuries, there may be increased potential for upper leg, chest, and head injuries

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.

A simulation has been developed at the Japan Automobile Research Institute to predict the fuel economy of HEVs, which are currently being developed in the advanced clean energy vehicle research and development project of MITI/NEDO (ACE Project). The ACE Project includes six types of HEV. The effect of hybrid components efficiency on fuel economy was evaluated by sensitivity coefficient. The results show that the fuel economy of HEVs can improve that of the base vehicle by two times. The sensitivity coefficient of the battery is largest in the FCEV, while that of the motor is largest in the series or series/parallel HEVs.

Acidified 2,4-dinitrophenylhydrazine (DNPH) solution, or DNPH-impregnated cartridges are commonly used for the collection of automotive exhaust carbonyl compounds. There are some DNPH-carbonyl compounds in not in use DNPH cartridges and DNPH solution. Furthermore, concentrations of automotive exhaust carbonyl compounds are decreasing according to improvement of the purification technology for automotive exhaust. Automotive exhaust carbonyl compounds become to be difficult to be analyzed with DNPH collection method, because of these two reasons. It is thought that reliable analysis of acrolein in automotive exhaust is very difficult because concentration of DNPH-acrolein in extracted solution is not stable. Furthermore, it is found out that DNPH-acrolein in DNPH-cartridge is disappeared for short time storage in this research.

Seat belts for rear passengers are not commonly used, even though they can significantly reduce fatalities. A passenger seat belt reminder (PSBR) is installed in order to encourage seat belt use, but the effectiveness of PSBRs on the rear seat passenger has not yet been proven. We have developed a methodology to assess PSBR effectiveness. There are two pathways to encourage seat belt use. The first is that PSBR directly facilitates the passenger's use. The second is to motivate the driver request passengers to use seat belts. In the experiment, we asked participants sitting in the driver's seat to select one of five ranks of likelihood to encourage the passenger when a PSBR was presented. We also asked participants sitting in the rear passenger seat to select the rank of likelihood to use the belt voluntarily with PSBR and that to use the belt when the driver requested. The degree of likelihood was quantified by averaging the assigned percentage values to the ranks.

ISO26262 was intended only for passenger cars but can be applied to motorcycles if the Controllability (C) is subjectively evaluated by expert riders. Expert riders evaluate motorcycle performance from the viewpoint of ordinary riders. However, riding maneuvers of ordinary riders have not been confirmed by objective data. For this reason, it is important to understand the basic characteristics of riding maneuvers of both expert and ordinary riders. This study seeks to confirm the compatibility between the riding maneuvers of expert riders and those of ordinary riders. The riding maneuvers and vehicle behavior of four expert riders and 16 ordinary riders were compared using the results of a test assuming normal running.

The hydrogen consumption of fuel cell vehicles (FCV) can be measured by the gravimetric, pressure and flow methods within a ±1% error. These are the methods acknowledged by ISO and SAE [1, 2], but require the test vehicles to be modified in order to supply hydrogen from an external, rather than the onboard tank. Consequently, technical assistance of the vehicle manufacturer is necessary for this modification, while various components in the test vehicle must be readjusted. For these reasons, a measurement method free of vehicle modification is in great demand. The present study therefore developed an “oxygen balance method” which determines the amount of hydrogen that has reacted with oxygen in the fuel cell stack by measuring the oxygen concentration in exhaust gas.

Electric vehicles have become more popular and may be involved in fires due to accidents. However, characteristics of fires in electric vehicles are not yet fully understood. The electrolytic solution of lithium-battery vehicles is inflammable, so combustion characteristics and gases generated may differ from those of gasoline cars. Therefore, we conducted fire tests on lithium-ion battery vehicles and gasoline vehicles and investigated the differences in combustion characteristics and gases generated. The fire tests revealed some differences in combustion characteristics. For example, in lithium-ion battery vehicles, the battery temperature remained high after combustion of the body. However, there was almost no difference in the maximum CO concentration measured 0.5 to 1 m above the roof and 1 m from the side of the body. Furthermore, HF was not detected in either type of vehicle when measured at the same positions as for CO.

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.

For applying ISO 26262 to motorcycles, controllability classification (C class evaluation) by expert riders is considered an appropriate technique. Expert riders have evaluated commercial product development for years and can appropriately conduct vehicle tests while observing safety restrictions (such as avoiding the risk of falling). Moreover, expert riders can ride safely and can stably evaluate motorcycle performance even if the test conditions are close to the limits of vehicle performance. This study aims to construct a motorcycle C class evaluation method based on an expert rider’s subjective evaluation. On the premise that expert riders can rate the C class, we improved a test procedure that used a subjective evaluation sheet as the concrete C class evaluation method for an actual hazardous event.

It was found that the finger blood pulse shows various fluctuations in different driving conditions. The nature of the finger blood pulse fluctuations was used for estimating a driver's internal state. Indexes suitable for expressing the fluctuations were moment and density; these indexes were calculated by using a return-map. However these results were measured by an off-line system and were calculated after the experiment. So, an on-line (real-time) system was needed in order to construct a driver's internal state monitoring system. As a first step, an online system for estimating the human internal state was developed. This system is available for estimating the human internal state every 30 seconds.

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.

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.

The SAE FCV Safety Working Group has been addressing fuel cell vehicle (FCV) safety for over 8 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable to 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. J2578 is currently being updated to clarify and update requirements so that it will continue to be relevant and useful in the future. An update to SAE J1766 for post-crash electrical safety was also published to reflect unique aspects of FCVs and to harmonize electrical requirements with international standards. In addition to revising SAE J2578 and J1766, the Working Group is also developing a new Technical Information Report (TIR) for vehicular hydrogen systems (SAE J2579).

The SAE Fuel Cell Vehicle (FCV) Safety Working Group has been addressing FCV safety for over 10 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 associated with the integration of hydrogen and electrical systems onto the vehicle 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. An update to SAE J1766 for post-crash electrical safety was also published in 2008 to reflect unique aspects of FCVs and to harmonize electrical requirements with international standards. In addition to SAE J2578 and J1766, the SAE FCV Safety Working Group also developed a Technical Information Report (TIR) for vehicular hydrogen systems (SAE J2579).

We have developed a new propane burner that satisfies the requirements of localized fire test which was presented in SAE technical paper 2011-01-0251. This paper introduces the specifications of this burner and reports its characteristics as determined from various fire exposure tests that we conducted in order to gather data. These tests included temperature and heat flux distribution on cylinder surfaces, which would be useful for the design of automotive compressed fuel cylinders. Our fire exposure tests included localized and engulfing fire tests to compare TPRD activation time, cylinder burst pressure and other parameters between different flame configurations and tests to identify the effects of an automotive compressed fuel cylinder on localized fire test results.

An impact test procedure with a legform addressing lower limb injuries in car-pedestrian accidents has been proposed by EEVC/WG17. Although a high frequency of lower limb fractures is observed in recent accident data, this test procedure assesses knee injuries with a focus on trauma to the ligamentous structures. The goal of this study is to establish a methodology to understand injury mechanisms of both ligamentous damages and bone fractures in car-pedestrian accidents. A finite element (FE) model of the human lower limb was developed using PAM-CRASH™. The commercially available H-Dummy™ lower limb model developed by Nihon ESI for a seated position was modified to represent the standing posture of pedestrians. Mechanical properties for both bony structures and knee ligaments were determined from our extensive literature survey, and were carefully implemented in the model considering their strain rate dependency in order to simulate the dynamic response of the lower limb accurately.

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.

It is becoming more and more necessary to achieve a sustainable low-carbon society by mobility not depending on oil. Electric vehicles are appropriate for such a society, but expensive battery cost and long charging time prohibit the promotion of EVs. One of the solutions is minimizing battery usage by ultra-low fuel efficiency, so we developed an ultrahigh-efficient electric commuter concept car “C-ta”, which requires as small a battery as possible. We assumed that drivers would use the car as a second car for short-distance daily use, such as commuting, shopping, transportation of family, etc. In order to improve fuel efficiency, we mainly considered an ultra-light weight body and chassis, to which CFRP (carbon fiber reinforced plastic) greatly contributes, ultra-low rolling resistance tires, and highly accurate vehicle control technology with four in-wheel motors.