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The aim of this research was to find vehicle characteristics including stiffness that is effective for compatibility performance. Compatibility is said to be affected by three factors: vehicle mass, geometry and stiffness (1, 2). Of these factors, stiffness has more flexibility at the design stage than vehicle mass and geometry which are limited by the vehicle application. However, the stiffness is assumed to have a conflict issue between the self-protection and the partner-protection (3). In this research, it was analyzed comprehensively how some defined factors such as stiffness, mass, crash stroke and other vehicle characteristics indices relate to each occupant injury rate of the case and its partner vehicle in the real-world accidents. Both “front-to-front” and “front-to-side” crash occupants were covered.

Continuous improvement of side airbag safety performance is an important step because it is associated with many public domain tests and regulations. Thus, occupant restraint with a side airbag is critical and it is necessary to develop tools that can be utilized to help in design of side airbags. Though many papers on side impact safety have been published, only a few papers are related to MADYMO simulations of side airbags. This paper describes an improved injury prediction and optimization approach using a MADYMO model for side impact. This model consists of 3 parts: dummy, trim and airbag in FEM. In this study, a side impact with a ES-2, EuroSID-2, was simulated in MADYMO as follows: First, component tests were conducted for trim and airbag respectively to establish correlation. Second, these component models were then integrated into a MADYMO model, which has high correlation with a crash simulator that is capable of replicating physical vehicle tests.

Flat panel displays for automobiles are facing a new era with the development of navigation systems. As navigation systems become more important as driver's assistance devices, development of birds-eye-view and 3D displays continues, as well as improvements for larger display screens and higher mounting positions. In response to the progress of mobile multimedia technologies, demands for larger display screens and larger aspect ratios have been increasing. Significance for improvements to anti-glare features or view angles has increased as they provide better visibility and the increase layout options. The use of human machine information interaction, which interfaces visual, audio and tactile senses, makes it possible to realize safer, more convenient and comfortable multimedia era vehicle

Most of the side impact air bag systems in the current market are designed to protect the thorax area only. The new Head and Thorax SRS Side Impact Air Bag system, which Nissan recently introduced into the market, was designed to help provide additional protection for the head in certain side impacts. The system may help protect occupant head contacts when the vehicle collides into a tree, or the high hood of a large striking vehicle. This paper introduces the additional features and function of the new Head and Thorax SRS Side Impact Air Bag system, and some evaluation results in laboratory testing.

Development of anti-whiplash technology is one of the hottest issues in the automotive safety field because of the frequent occurrence of rear impact accidents. We analyzed the whiplash mechanism and conducted a study to seek the optimized seat characteristics with BioRID II and MADYMO simulations. A parameter study was made to construct a conceptual theory to decrease NIC, Neck Injury Criteria, with the MADYMO model. As a result of the study, head restraint position and seatback stiffness were found to affect dummy movement and injury values. Applying the NIC mechanism and the influential parameters to the MADYMO model, the optimized seat characteristics for whiplash prevention were obtained.

CFRP (Carbon Fiber Reinforced Plastic) materials have been extensively used in racing cars because of its high stiffness and lightweight. Recently, car crash safety is becoming increasingly important even for racing cars. CFRP has also a merit on crash safety because it offers the freedom to set the material characteristics where needed and the needless of considering remaining length after the impact. In this analysis, a multi-layered shell material is applied to reproduce the crash characteristics of the CFRP structure. Fundamental crash test data of simple specimens are used to verify the material characteristics of CFRP, and applied to the Crash-Box of a Nissan GT500 racing car. The simulation showed good correlation with the actual test, and the final design was based on these analyses without the need of repeating impact tests.

The accuracy of FE (Finite Element) side impact dummy characteristics is important when using FE vehicle model for vehicle development. This study evaluated the response characteristics of FE SID-lls dummy (5TH female) model that was developed by FTSS using FE code PAM-CRASH™. This paper will describe improvements of computational evaluation method and FE dummy model in the sled tests simulated interior. For the various impact conditions, good correlation between FE calculation and the sled test results was obtained.

Flow velocity distributions in the passenger compartment were measured from visualized images of particle flow paths obtained with a full-scale model. The flow paths were visualized using an approach that combined a particle tracing method with a pulse-laser light technique. Air was used as the fluid medium with the full-scale passenger compartment model and water was used as the fluid medium with a one-fourth scale model. A comparison of the results obtained with the two models confirmed that there was good agreement between the flow velocity distributions. Using the full-scale model, measurements were also made of the flow velocity distributions when two dummies were placed in the front-seats.

Evaluations of dummy injury readings obtained in regulatory crash tests and new car assessment program tests provide indices for the development of crash safety performance in the process of developing new vehicles. Based on these indices, vehicle body structures and occupant restraint systems are designed to meet the required occupant injury criteria. There are many types of regulatory tests and new car assessment program tests that are conducted to evaluate vehicle safety performance in side impacts. Factoring all of the multiple test configurations into the development of new vehicles requires advanced design capabilities based on a good understanding of the mechanisms producing dummy injury readings. In recent years, advances in computer-aided engineering (CAE) tools and computer processing power have made it possible to run simulations of occupant restraint systems such as side airbags and seatbelts.

The progress of computer technology and CAE methodology makes it possible to simulate dummy injury readings in vehicle crash simulations. Dummy neck injuries are generally more difficult to simulate than injuries to other regions such as the head or chest. Accordingly, improving the accuracy of dummy neck injury data is a major concern in frontal occupant safety simulations. This paper describes the use of an advanced airbag modeling methodology to improve the accuracy of dummy neck injury readings. First, the following items incorporated in the advanced airbag model are explained. (1) The Finite Point Method (FPM) is used to simulate the flow of gas. (2) A folding model is applied to simulate the folded condition. (3) The fabric material properties used in the simulation take into account anisotropy in the fiber directions and the nonlinear, hysteresis characteristics of stiffness.

A side impact is one of the severest crash configurations among real-world accidents. In the US market, even though most vehicles have achieved top ratings in crash performance assessment programs in recent years, there has hardly been any sign of a decline in side-impact fatalities for the last few years, according to statistics retrieved from the National Highway Traffic Safety Administration’s Fatality Analysis Reporting System. In response to this trend, the Insurance Institute for Highway Safety (IIHS) is planning to introduce a new test protocol for side impact assessment. One of the points to be clarified in current side impact tests is whether the present side moving deformable barrier (MDB), which includes the barrier face and cart, faithfully reproduces a real-world car-to-car crash.

In this report, we proposed an objective evaluation method of the seat lateral support according to the mechanisms to create the performance differences that we reported previously [1]. First, we showed an effect of scrutinizing Seat Pressure Distribution's change during vehicle turn to gain a quantitative index for explaining subjective evaluation results. Second, we showed the examples of the differences of the results according to the subjects and selected the best-correlated subject among them with a market survey result. Then, we contrived a loading condition to SAE manikin to reproduce the subject's Seat Pressure Distribution. Final, by a specific calculation of the Seat Pressure Distribution, the method to indicate the performance rating that had strong correlation with market survey was clarified.

Seat lumbar support is thought to be essential for seating comfort as it plays important role in the driver's fatigue during long term driving. We tried to evaluate the lumbar support performance objectively with Seat Pressure Distribution. First, the tolerance in the measurement was eliminated by application of ASPECT manikin that reproduced a human seating torso posture [1, 2]. Second, an analysis method to visualize the seat support balance on the human back was developed. Third, a hypothesis for the optimal support balance to minimize the fatigue was proposed according to the fatigue growing mechanisms. Examining the deviation of each seat result from the optimal support, the performances were quantitatively evaluated. In addition to that, the effect of the lumbar support adjuster was taken into consideration to predict the market evaluation more precisely.

This paper presents a method for optimizing occupant restraint system parameters in vehicle frontal crashes. Simulation models incorporating restraint systems and dummies are used for predicting injury indexes. A full-scale survey of all of the design parameters related to the injury indexes would require a vast number of simulations. Therefore, the Design of Experiments (DOE) method involving a minimum number of experiments is more realistic. However, dummy behavior often shows discontinuity if the dummy comes in contact with the steering wheel, so it is not predicted well with usual DOE methods. This paper shows how to incorporate such discontinuity in a DOE study and how to optimize the restraint system parameters to reduce occupant injury indexes. It also discusses the feasibility of this method for integrated optimization of 50th percentile and 5th percentile dummies.

This paper outlines the most important characteristics of the practical type air bag now being developed by Nissan Motor Co., Ltd. It explains the results of various occupant protection tests conducted at 16 to 64 km/h (10 to 40 mph) speeds, and the related problems we have encountered. It further discusses the effects of several type of occupant protection systems installed on small-sized cars and the relationships between those effects and limited crash speeds. An examination and analysis of air bag performance test results is also included. Despite all efforts made, there yet remain several problems to be solved. For example, (a) in high-speed collisions it is difficult to reduce femur load by means of air bag systems alone; (b) passengers such as three-year-old infants and 5th percentile female adults display a tendency toward submarining: (c) when the environmental temperature is extremely low, it is difficult for the air bag to meet the MVSS Occupant Protection Requirements.

An automatic, falling, occupant-protecting net is being developed for spreading in front of automobile occupants in the time interval between vehicle impact and occupant collision. The device is designed to counteract forward body acceleration and minimize head, neck, and chest injuries. This device was investigated by sled and barrier tests using anthropomorphic dummies. Significant improvements in occupant kinematics and remarkable reduction in head and chest impact force has been observed. Some problems such as whiplash injury await solution but continuing investigation of proposed measures of correction show that they are not insurmountable.

LCD instrument panels incorporating the following new techniques have been developed and put into practical use. The back illumination using white-light cold cathode discharge tubes, coupled with added dye and twisted nematic LCD panels, represents a liquid crystal display with good visibility and high-quality appearance. In addition, a fast display response time of less than 0.1 seconds at −30°C, and a two-toned display on a single segment have been achieved by the adoption of a heating system and three polarizers.

This paper discusses the influence of variations in the vehicle deceleration curve on dummy injury criteria for a passive seat belt-restrained dummy using MVMA-2D crash victim simulation and sled tests for frontal crash analysis. The MVMA-2D simulation and sled tests verified that the vehicle deceleration curve exhibiting the higher Residual Deformation (RD) produces smaller dummy injury criteria. Also, using MVMA-2D simulation, the peak levels of the first and second waves were changed as parameters to ensure accurate evaluation of the influence of the deceleration curve on dummy injury criteria. Moreover, this paper also discusses Nissan's use of both occupant kinematic simulation and vehicle structural sisulation for frontal crash in the development of its vehicles.

A human-centered systems analysis was applied to the adverse aircraft weather encounter problem in order to identify desirable functions of weather and icing information. The importance of contingency planning was identified as emerging from a system safety design methodology as well as from results of other aviation decision-making studies. The relationship between contingency planning support and information on regions clear of adverse weather was investigated in a scenario-based analysis. A rapid prototype example of the key elements in the depiction of icing conditions was developed in a case study, and the implications for the components of the icing information system were articulated.

This paper describes the equivalent temperature based on the mesh-free simulation proposed by the previous papers (Part1 and Part2) under the transient heating condition in a 3D-CAD vehicle cabin including the thermal manikin which takes into account the clothing shape. For this purpose, firstly, the experiments of vehicle cabin measuring for the thermal environment including the equivalent temperature are carried out under the transient heating condition. Then, the calculated results of the thermal environment in the vehicle cabin are compared with time series experimental data under the transient condition. They correspond to the experiments including transient changes well. The transient calculated equivalent temperature of thermal manikin is also compared with experiments. As a result, since it is difficult to control the thermal manikin ideally in the experiment, it is difficult to compare the transient behavior.