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Riley P.O.,University of Virginia | Arregui-Dalmases C.,University of Virginia | Arregui-Dalmases C.,Polytechnic University of Catalonia | Purtserov S.,University of Virginia | And 8 more authors.
Traffic Injury Prevention | Year: 2012

A test series involving direct right-side impact of a moving wall on unsupported, unrestrained cadavers with no arms was undertaken to better understand human kinematics and injury mechanisms during side impact at realistic speeds. The tests conducted provided a unique opportunity for a detailed analysis of the kinematics resulting from side impact. Specifically, this study evaluated the 3-dimensional (3D) kinematics of 3 unrestrained male cadavers subjected to lateral impact by a multi-element load wall carried by a pneumatically propelled rail-mounted sled reproducing a conceptual side crash impact. Three translations and 3 rotations characterize the movement of a solid body in the space, the 6 degrees of freedom (6DoF) kinematics of 15 bone segments were obtained from the 3D marker motions and computed tomography (CT)-defined relationships between the maker array mounts and the bones. The moving wall initially made contact with the lateral aspect of the pelvis, which initiated lateral motion of the spinal segments beginning with the pelvis and moving sequentially up through the lumbar spine to the thorax. Analyzing the 6DoF motions kinematics of the ribs and sternum followed right shoulder contact with the wall. Overall thoracic motion was assessed by combining the thoracic bone segments as a single rigid body. The kinematic data presented in this research provides quantified subject responses and boundary condition interactions that are currently unavailable for lateral impact. © 2012 Taylor and Francis Group, LLC.


Nakamura Y.,Japan Automobile Manufacturers Association Inc.
Proceedings of the International Display Workshops | Year: 2012

JAMA executed the road tests to analyze driver's workload of various operations to the navigation systems. As a result, the JAMA guidelines regulated the world's first numerical criterion for display operations while driving. The paper describes the grounds of the criterion.


Antona-Makoshi J.,Japan Automobile Research Institute | Yamamoto Y.,Japan Automobile Research Institute | Kato R.,Japan Automobile Research Institute | Sato F.,Japan Automobile Research Institute | And 3 more authors.
International Journal of Automotive Engineering | Year: 2015

An anatomically detailed age-specific finite element model of the thoracic region of an average size Japanese elderly male was developed. The model was validated against original series of experimental data both at component and at assembled-structural level. With the validated model, a simulation based age-dependent parametric study was conducted. The results show that rib cortical bone and muscle softening due to ageing affect the structural thoracic response under controlled belt loading conditions. The thoracic model will be implemented into a full scale elderly model and is intended to support the deployment of elderly-specific safety improvement strategies. © 2015 Society of Automotive Engineers of Japan, Inc.


De Dios E.D.P.,University of Navarra | Kindig M.,University of Virginia | Arregui-Dalmases C.,University of Navarra | Crandall J.,University of Virginia | And 4 more authors.
International Journal of Crashworthiness | Year: 2011

Efforts to mitigate thoracic injury under lateral impact require an understanding of the structural and fracture characteristics of individual ribs under lateral loading. While a number of studies have loaded segments of rib under three-point bending, this study is the first to investigate lateral loading onto entire ribs. Fifteen individual ribs were extracted, positioned upright and a lateral displacement at 1 m/sec was applied. Displacements at the time of fracture were relatively constant across rib levels at 18.3 ±3.7 mm. Fracture forces ranged from 27 N to 270 N at the anterior extremity and 103 N to 326 N at the posterior extremity; this was also insensitive to rib number. The strain gages indicated that the point immediately opposite the loader on the rib's internal surface experienced the highest tensile strains, while elsewhere the internal surface was in compression and the external surface was in tension. This structural-level rib characterisation can help to better understand the mechanisms of thoracic injury under lateral impact. © 2011 Taylor & Francis.


Kitamura S.,Japan Automobile Manufacturers Association Inc.
Annual Fuels and Lubes Asia Conference and Exhibition | Year: 2013

A presentation on JAMA engine oil activities covers engine design trends; improvement of engine oil quality; recommendations and benefits of low viscosity engine oil; international standardization of PCMO; Japanese OEM's recommendation on PCMO (Passenger Car Motor Oil); and market trends in Asia. This is an abstract of a paper presented at the 19th Annual Fuels & Lubes Asia Conference (Bangkok, Thailand 3/13-15/2013).


Matsuki M.,Japan Automobile Manufacturers Association Inc.
Annual Fuels and Lubes Asia Conference and Exhibition | Year: 2013

A discussion covers the exhaust emission regulation trends and global harmonization; examples of fuel quality improvement, which include fuel quality guideline update for World Wide Fuel Charter and the UN and biodiesel study in Japan auto-oil program; and future direction of gasoline and diesel fuels. This is an abstract of a paper presented at the 19th Annual Fuels & Lubes Asia Conference (Bangkok, Thailand 3/13-15/2013).


Antona-Makoshi J.,Japan Automobile Research Institute | Yamamoto Y.,Japan Automobile Research Institute | Kato R.,Japan Automobile Research Institute | Sato F.,Japan Automobile Research Institute | And 3 more authors.
Traffic Injury Prevention | Year: 2015

Objectives: The ultimate goal of this research is to reduce thoracic injuries due to traffic crashes, especially in the elderly. The specific objective is to develop and validate a full-body finite element model under 2 distinct settings that account for factors relevant for thoracic fragility of elderly: one setting representative of an average size male and one representative of an average size Japanese elderly male. Methods: A new thorax finite element model was developed from medical images of a 71-year-old average Japanese male elderly size (161cm, 60 kg) postmortem human subject (PMHS). The model was validated at component and assembled levels against original series of published test data obtained from the same elderly specimen. The model was completed with extremities and head of a model previously developed. The rib cage and the thoracic flesh materials were assigned age-dependent properties and the model geometry was scaled up to simulate a 50th percentile male. Thereafter, the model was validated against existing biomechanical data for younger and elderly subjects, including hub-to-thorax impacts and frontal impact sled PMHS test data. Finally, a parametric study was conducted with the new models to understand the effect of size and aging factors on thoracic response and risk of rib fractures. Results: The model behaved in agreement with tabletop test experiments in intact, denuded, and eviscerated tissue conditions. In frontal impact sled conditions, the model showed good 3-dimensional head and spine kinematics, as well as rib cage multipoint deflections. When properties representative of an aging person were simulated, both the rib cage deformation and the predicted number of rib fractures increased. The effects of age factors such as rib cortical thickness, mechanical properties, and failure thresholds on the model responses were consistent with the literature. Aged and thereby softened flesh reduced load transfer between ribs; the coupling of the rib cage was reduced. Aged costal cartilage increased the severity of the diagonal belt loading sustained by the lower loaded rib cage. Conclusions: When age-specific parameters were implemented in a finite element (FE) model of the thorax, the rib cage kinematics and thorax injury risk increased. When the effect of size was isolated, 2 factors, in addition to rib material properties, were found to be important: flesh and costal cartilage properties. These 2 were identified to affect rib cage deformation mechanisms and may potentially increase the risk of rib fractures. © 2015, © Jacobo Antona-Makoshi, Yoshihiro Yamamoto, Ryosuke Kato, Fusako Sato, Susumu Ejima, Yasuhiro Dokko, and Tsuyoshi Yasuki. Published with license by Taylor & Francis


Isshiki T.,Japan Automobile Research Institute | Konosu A.,Japan Automobile Research Institute | Takahashi Y.,Japan Automobile Manufacturers Association Inc.
2014 IRCOBI Conference Proceedings - International Research Council on the Biomechanics of Injury | Year: 2014

The current test methods using a legform impactor cannot appropriately evaluate the probability of pedestrian lower limb injuries when applied to vehicles with high bumpers (high-bumper vehicles) because of a lack of pedestrian upper body part/function in the impactors. Therefore, since 2010 we have been developing a legform impact test method that can evaluate the probability of pedestrian lower limb injuries when applied to any type of vehicle, including high-bumper vehicles. In this research, as the second step of our study, we developed a finite element (FE) model of a Simplified Upper Body Part (SUBP) that can appropriately consider the influences of the upper body part of pedestrians. First of all, because it can be considered that the influences of the upper body part of pedestrians are passed on to the lower limb via the hip joint located at the top of the lower limb, we analyzed the influence of differences in load conditions applied to the hip joint on the probability of lower limb injuries. As a result, we identified factors that significantly influence the probability of lower limb injuries. Next, we developed a SUBP FE model considering the above-mentioned influential factors using the optimization method. As a result, we succeeded in developing a SUBP FE model that can appropriately consider the influences of the upper body part of pedestrians.


Tagawa T.,Japan Automobile Research Institute | Uchida N.,Japan Automobile Research Institute | Kawakoshi M.,Japan Automobile Research Institute | Aga M.,Japan Automobile Manufacturers Association Inc.
SAE Technical Papers | Year: 2010

Naturalistic driving data has been accumulated by driving data recorders to understand factors that contribute to collisions. Among the rear end conflicts at signalized intersections in the data, conflict data between the following vehicles and suddenly stopping lead vehicles were frequently observed just after their start. To investigate the following drivers' behaviour in a realistic driving situation without collision danger, an instrumented vehicle equipped with a liquid-crystal display ahead of the windshield was developed, and an experiment reproducing such conflict on the display was conducted. It was found that a lead vehicle's rapid start (2.8m/s 2 on average) before quitting its right turn caused the following vehicle's brake reaction time to be longer than a slow start (0.8m/s 2 on average) did. This result suggests that a following driver's premature decision to start rapidly increases the risk of rear end collisions. Copyright © 2010 SAE International.


Isshiki T.,Japan Automobile Research Institute | Konosu A.,Japan Automobile Research Institute | Takahashi Y.,Japan Automobile Manufacturers Association Inc.
SAE International Journal of Transportation Safety | Year: 2015

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. The results show that the upper body significantly influenced the bending load generated in the lower limb of a pedestrian. This influence was found to be bumper height dependent. In addition, method of compensation for the lack of the upper body by increasing impact height of the FlexPLI was found not to work for high-bumper vehicles effectively. These results suggest the need to develop a new test method that appropriately incorporates upper body representation regardless of bumper height. Copyright © 2015 SAE International.

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