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This paper describes the methods adopted to improve the image quality of the all-around view system. This system uses multiple vehicle-mounted cameras to capture images of the circumstances around the vehicle. The images undergo viewpoint transformation and are synthesized to create a single image seen from a virtual perspective overhead. The specific methods discussed here concern optimization of the design parameters for the camera orientation and a camera calibration method that does not involve physical movement of the cameras.

Hydraulic engine mounts(HEM) are replacing conventional rubber mounts to provide better ride quality and to reduce noise. However, detailed analysis of the HEM is needed to predict ideal performance conditions. In this study, the optimum design of a HEM is modelled using design optimization theory for a dynamic absorber. After determining ideal behavior by simulation, an experimental mounts is designed and tested to verify the model.

This study focused on European NCAP activities of introducing a new head protection evaluation procedure, as proposed by BASt (Federal Highway Research Institute - GERMANY). Various kinds of E-bikes are available in the market, ranging from E-bikes that have a small motor to assist the rider’s pedal-power i.e., pedelecs to somewhat more powerful E-bikes which is similar to a moped-style scooter. This paper focused on identifying the factors influencing bicyclist head kinematics during bicycle vs. passenger vehicle (PV) collisions at the intersection. Two AM50 bicyclist FE models are developed using i) GHBMC Human Body Model (HBM) and ii) WorldSID (WS) side impact dummy. Head kinematics of bicyclists of pedal-assist E-bike and normal bike were compared using CAE simulation. It is found that the vehicle’s impact velocity, type of bicycle, the mass of E-bike and bicycle traveling speed will influence the head kinematics.

This paper proposes a new hierarchical optimization technique for the vehicle body structure, by combining topology optimization and shape optimization based on the traction method. With the proposed approach, topology optimization is first performed on the overall allowable design domain in 3D. The surface is extracted from the optimization result and converted to a thin shell structure. Shape optimization based on the traction method is then applied to obtain an overall optimal body shape. In the shape optimization process, iterative calculations are performed in the course of consolidating parts by deleting those whose contribution is small. The result obtained by applying this method to the front frame structure of a vehicle is explained. The resultant optimal shape has stiffness greater than or equal to the original structure and is 35% lighter. This confirms the validity of the proposed technique. It was found, however, that some issues remain to be addressed.

The authors have proposed a new method to identify the important information which links to the basic principle of the design's physical behavior by using CAE technology, and this method was named as CAP (Computer-Aided Principle).This method can help the engineers to grasp the basic physical characteristic that governs the first-order behavior. In this study, the authors applied CAP to the simulations of the design of frontal crash phenomena, which are difficult to understand because of the problem of strong nonlinearity, and explored the possibilities for using CAP. The correlative physical parameters thus obtained can help designers to understand the essence of the phenomena involved.

The demands on valve seat insert materials, in terms of providing greater wear-resistance at higher temperatures, enhanced machinability and using non-environmentally hazardous materials at a reasonably low cost have intensified in recent years. Due therefore to these strong demands in the market, research was made into the possibility of producing a new valve seat insert material. As a result a high speed steel based new improved material was developed, which satisfies the necessary required demands and the evaluation trials, using actual gasoline engine endurance tests, were found to be very successful.

The spray formation and mixing processes in a direct-injection gasoline engine are examined by using a sophisticated air flow calculation model and an original spray model. The spray model for a spiral injector can evaluate the droplet size and spatial distribution under a wide range of parameters such as the initial cone angle, back pressure and injection pressure. This model also includes the droplet breakup process due to wall impingement. The arbitrary constants used in the spray model are derived theoretically without using any experimental data. Fuel vapor distributions just before ignition and combustion processes are analyzed for both homogeneous and stratified charge conditions.

In a previous study, we developed and validated a new driving posture focused on biomechanical loads for physical fatigue reduction in static long-term sitting. In this study, the posture was evaluated in dynamic long-term driving condition by qualitative and quantitative measurements. The results showed physical fatigue of the new posture was halved in comparison with the one of the conventional posture in same car by subjective evaluations. Physiological indices had same tendency with subjective evaluations. From the results, we extracted seven physiological indices as good measures of physical fatigue while driving. Therefore, fatigue reduction of the new posture was qualitatively validated by physiological measurements.

The Computer-Aided Principle (CAP) is applied in this study as an effective approach to the crashworthiness design of the vehicle front-end structure. With this method, correlative parameters are extracted in a parametric study by using a cluster analysis. The results can help engineers to understand the fundamental mechanisms of structural phenomena. A simulation example of an offset frontal crash against a deformable barrier (ODB) is presented to show the effectiveness of the proposed method.

With SUVs and minivans accounting for a larger share of the US market in the past decade, rollover accidents have drawn greater attention, leading to more active research from different perspectives. This ranges from investigations for elucidating the basic causes and mechanisms of rollover accidents to studies of more advanced occupant protection measures. As the phenomenon of a rollover accident is longer in duration than frontal, side or rear impacts, it is relatively difficult [1] to simulate such accidents for experimental verification and also for proper evaluation of occupant restraint system performance. In this work, we focused on the trip-over type, which occurs most frequently, and performed simulations to reproduce real-world rollover accidents by combining PC-Crash and FEA.

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.

The probability or risk of traffic accidents must be estimated quantitatively in order to implement effective traffic safety measures. In this study, various statistical data and probability theory were used to examine a method for predicting the risk of crossing-collisions, representing a typical type of accident at intersections in Japan. Crossing-collisions are caused by a variety of factors, including the road geometry and traffic environment at intersections and the awareness and intentions of the drivers of the striking and struck vehicles. Bayes' theorem was applied to find the accident probability of each factor separately. Specifically, the probability of various factors being present at the time of a crossing-collision was estimated on the basis of traffic accident data and observation survey data.

Increasing expectations for stability at high speed call for the improvement of cars' aerodynamic performance, in particular lift reduction. However, due to styling constraints, traditional spoilers must be avoided and replaced by other solutions like underfloor components. Flow simulation is expected to be a useful tool for lift prediction, but the conventional models used so far did not represent complex geometry details such as the engine compartment and underfloor, and accuracy was insufficient. In the present study, a full vehicle simulation model, including the engine compartment and underfloor details, was used. Other improvements were also made such as optimization of the computational grid and the setting of boundary conditions for reproducing wind tunnel experiments or actual driving, making it possible to predict lift variations due to vehicle geometry changes.

In general, the improvement of vehicle body stiffness involves a trade-off with the body weight. The objective of this research is to derive the lightest-weight solution from the original vehicle model by finding the optimized spot-weld layout and body panel thickness, while keeping the body stiffness and number of spot welds constant. As the first step, a method of deriving the optimal layout of spot welds for maximizing body stiffness was developed by applying the topology optimization method. While this method is generally used in shape optimization of continuous solid structures, it was applied to discontinuous spot-weld positions in this work. As a result, the effect of the spot-weld layout on body stiffness was clarified. In the case of the body used for this research, body stiffness was improved by about 10% with respect to torsion and vertical and lateral bending.

In order to reduce traffic accidents and ease traffic congestion utilizing ITS (Intelligent Transportation System), a large-scale FOT (Field Operational Test) involving 2,000 ordinary drivers was launched in October 2006 in the city of Yokohama in Kanagawa, Japan. The test is slated to continue through March 2009. Target applications include Intersection Collision Avoidance using V-I (Vehicle-to-Infrastructure) communication, ISA (Intelligent Speed Advisory) using digital maps in the vehicle navigation system, and the probe system, which provides detailed traffic information. In this paper, the progress of this FOT will be introduced.

The brake-operated pre-crash seatbelt system retracts the seatbelt webbing by activating an electric motor attached to the seatbelt retractor. Detection of emergency braking is used as a trigger to activate the motor. Retracting the seatbelt helps to reduce an occupant's forward movement due to inertial force acting on the occupant's body during deceleration in braking. Addtionally, retraction of the seatbelt webbing also helps existing occupant restraint devices to work more effectively in a crash. The effectiveness of the pre-crash system was evaluated by considering two conditions combined. One involved the dynamic behavior of the vehicle and occupants prior to a crash. The other concerned the safety performance of the vehicle during the crash event. Experiments were conducted to measure the behavior of the vehicle and occupants under emergency braking prior to a crash.

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.

The numerical relations between occupant restraint systems and injury indexes were investigated by multi-parameter optimization of an integrated restraint system model of frontal crash simulations. This paper proposes a method of optimizing restraint systems in two types of test configurations: a 35-mph full overlap crash model and a 40-mph 40%-offset crash model.