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In the initial design stage, it is important to discuss what kind of body concept is effective from a viewpoint of environment burden reduction. This paper describes the importance of both weight reduction and recycling through conducting LCA (Life Cycle Assessment) for four kinds of body structures. In addition, using each software, DFMA (Design for Manufacture and Assembly), DFE (Design for Environment) and LCA to parts unit, each effectiveness was discussed through the assessment of the material-hybrid body.

Many efforts have been made to understand the mechanism of whiplash injury. Recently, the cervical facet joint capsules have been focused on as a potential site of injury. An experimental approach has been taken to analyze the vertebral motion and to estimate joint capsule stretch that was thought to be a potential cause of pain. The purpose of this study is to analyze the kinematics of the cervical facet joint using a human FE model in order to better understand the injury mechanism. The Total Human Model for Safety (THUMS) was used to visually analyze the local and global kinematics of the spine. Soft tissues in the neck were newly modeled and introduced into THUMS for estimating the loading level in rear impacts. The model was first validated against human test data in the literature by comparing vertebrae motion as well as head and neck responses. Joint capsule strain was estimated from a maximum principal strain output from the elements representing the capsule tissues.

In FOA (First Order Analysis) any vehicle body structure might be interpreted as a collective simple structure that can be decomposed into 3 fundamental structure types. The first structure is the “BEAM”, whose cross sectional properties as well as its material dominates the mechanical behavior, the second is the “PANEL (shear panel, plate, and shell)”, whose mechanical behavior can be varied by changing its geometrical properties in the thickness direction, i.e. adding beads or flanges. The third structure is the “JOINT”, which connects the proceeding structures, and transfer complex three-dimensional loads with three-dimensional deformation. In the present work, we shall propose a methodology to identify a portion of an arbitrary FE model of an automotive body structure, with a “BEAM” structure in the FOA approach. In the latter chapter of this paper, cross section loads will be related with cross sectional properties in the aspect of the element strain energy concept.

Approximately 20% of traffic fatalities in United States 2012 were caused by rollover accidents. Mostly injured parts were head, chest, backbone and arms. In order to clarify the injury mechanism of rollover accidents, kinematics of six kinds of Anthropomorphic Test Devices (ATD) and Post Mortem Human Subjects (PMHS) in the rolling compartment, whose body size is 50th percentile male (AM50), were researched by Zhang et al.(2014) using rollover buck testing system. It was clarified from the research that flexibility of the backbone and thoracic vertebra affected to occupant’s kinematics. On the other hand, the kinematics research of body size except AM50 will be needed in order to decrease traffic fatalities. There were few reports about the researches of occupant kinematics using FE models of body sizes except AM50.

A method for applying soap film geometry to an automobile body structure has been developed. Its curved surface reduce both interior noise and damping material application because of its high rigidity and uneven deformation mode. This paper demonstrates these mechanism, benchmarks their performance with conventional flat and bead panels and presents an application to the floor panel of an automobile body.

Teammate Advanced Drive is a driving support system with state-of-the-art automated driving technology that has been developed for customers’ safe and secure driving on highways based on the Toyota’s Mobility Teammate Concept. This SAE Level 2 (L2) system assists overtaking, lane changes, and branching to the destination, in addition to providing hands-free lane centering and car following. The automated driving technology includes self-localization onto a High Definition Map, multi-modal sensing to cover 360 degrees of the surrounding environment using fusion of LiDARs, cameras, and radars, and a redundant architecture to realize fail-safe operation when a malfunction or system limitation occurs. High-performance computing is provided to implement deep learning for predicting and responding to various situations that may be encountered while driving.

Due to the relative high speed and short distance between the door and occupant, side impact presents a challenging task when analyzing the input force from the door to the occupant. The new FMVSS214 Final Rule in 2007 and the new NCAP in 2008 mandated the use of a SID-IIs in the oblique pole impact test and in the rear seat during an MDB side impact test. Therefore, a high-precision measurement and calculation of the three-dimensional dummy kinematics, as well as the interaction of force inside the dummy (internal force) and force exerted from outside the dummy (external force) will help provide efficient evaluation of design requirements for the door trim and supplemental restraint systems that meet legally mandated requirements.

Collisions between opened doors and approaching vehicles such as bicycles are common occurrences in urban areas around the world. For example, in Chicago, 20% of all bicycle accidents involve collisions with doors, which occur over 300 times a year. In addition, there are concerns about a further rise in accidents due to the recent increase in home delivery services and bicycle commuting during the COVID-19 pandemic. Some advanced driver assistance systems (ADAS) that are designed to help prevent this type of accident have already been introduced. These systems detect approaching vehicles with sensors and alert the person opening the door via LED lights or a buzzer when the door is opened. The occupant must understand the meaning of the alert and stop opening the door quickly to prevent an accident. However, if the occupant is an elderly person or a child, it is difficult to stop opening the door quickly.

We have developed a Hall effect device based height sensor of a smaller size, and with higher temperature operation durability, as compared to conventional devices. Downsizing of the sensor is realized by decreasing a number of parts, and by employing a short bearing. Improvement in heat resistance is achieved by adopting an IC with sufficient heat resistance and a SmCo magnet with high coercive force. In addition, a sensor of a high degree of accuracy is accomplished by improvements in linearity and robustness of magnetic characteristics. Development of a small, heat-resistant and accurate height sensor will promote the spread of systems using a height sensor, such as a High Intensity Discharge (HID) headlamp.

This paper describes that a method has been developed to estimate the range of the scatter of Head Injury Criterion (HIC) values in pedestrian impact tests, which could help to reduce the range of the scatter of HIC values by applying the stochastic method for Finite Element (FE) analysis. A major advantage of this method is that it enables the range of scatter of HIC values to be estimated and to explain the mechanics of the behavior. The test procedure of pedestrian impact allows some tolerances for the resultant conditions of impact such that the distance of actual impact location from the selected point is within 10 mm and the impact velocity is within ±0.7 km/h [1]. A HIC value calculated by impact simulation under a deterministic impact condition with the nominal input data does not necessarily represent the variation of measured data in impactor tests.

1 The principal characteristics required of sealing materials used in the body shop have focused on their adhesion to oily steel sheets and quick curing performance. Means for attaining these characteristics have been narrowed down to a basic resin system and a curing system. Various techniques have been studied to ensure proper anti-corrosion performance at the sealer application boundaries and thin application areas. They include the addition of anti-corrosion fillers, the provision of conductivity (through electro-deposition), and the application of a micro foam film over the application boundaries. Thus, prospects for attaining the same level of anti-corrosion performance as existing materials have been achieved.

This paper describes the development of a simplified fracture finite element (FE) model for resistance spot welds (RSW) of ultra-high-strength steel (UHSS) that can be incorporated into large-scale vehicle FE model. It is known that the RSW of UHSS generates two types of fracture modes: heat-affected zone (HAZ) and nugget zone fractures. Lap shear and peeling coupon tests using UHSS sheets found that the different RSW fracture modes occurred at different nugget diameters. To analyze this phenomenon, detailed simulated coupon tests were carried out using solid hexahedral elements. The analytical results revealed that RSW fractures are defined by both the application of plastic strain on the elements and the stress triaxiality state of the elements. A detailed model incorporating a new fracture criteria model recreated the different UHSS RSW fracture modes and achieved a close correlation with the coupon test results.

Weight reduction for a fuel cell vehicle (FCV) is important to contribute a long driving range. One approach to reduce vehicle weight involves using a carbon fiber reinforced plastic (CFRP) which has a high specific strength and stiffness. However, a conventional thermoset CFRP requires a long chemical reaction time and it is not easy to introduce into mass production vehicles. In this study, a new compression-moldable thermoplastic CFRP material for mass production body structural parts was developed and applied to the stack frame of the Toyota Mirai.

Since bumper reinforcements are positioned at front/rear ends of vehicles, weight reduction of the bumper reinforcements enhances vehicle dynamic performance by reducing a yaw moment of inertia. CFRP (Carbon Fiber Reinforced Plastic) composites are attractive lightweight materials due to their excellent specific strength and rigidity. However, because of their relatively high cost, applications of CFRP materials to vehicle structural parts are limited. In this study we have developed a lightweight, structural part, which consists of a thin-walled Al (Aluminum) bumper reinforcement with a UD (Unidirectional)-CFRP sheet. The intention is to prevent an increased part cost by reducing the amount of Al and by minimizing the amount of CFRP. Compared to Al, UD-CFRP sheets have even higher tensile strength and modulus. When vehicles crash, bumper reinforcements may be subjected to bending force.

A highly anti-corrosive organic-inorganic hybrid paint for automotive steel parts has been developed. The inorganic component included in the paint is silicon dioxide (SiO2), which has the capability to passivate zinc. By application of the paint on a trivalent chromatetreated zinc-plated steel sheet or a trivalent chromate-treated zinc-nickel-plated steel sheet, high anti-corrosion protection can be provided to steel materials. Particularly in the case of application over a zinc-nickel-plated steel sheet, 0 mm corrosion depth after a cyclic corrosion test (CCT) of 450 cycles was demonstrated.

In this study, we evaluated subjective nighttime discomfort-glare responds on three different types of planar and non-planar driver-side mirrors on two age groups. Fifty-six individuals (28 young [18-35 years] and 28 old [65 years and over]) participated in this experiment. Subjective discomfort-glare rating scores on three different types of driver-side mirrors were assessed utilizing De Boer's rating scale in a controlled nighttime driving environment (laboratory ambient illuminant level - l lux with headlight turned off). Three driver-side mirrors included: planar (“flat mirror” - reflectance ratio of 39.12%) and nonplanar (“curved mirror” - reflectance ratio of 8.78% and “blue mirror” - reflectance ratio of 7.77%; R=1400mm). The results indicated that with the same glare level (as measured by angle of incidence and illuminance on the front of the eyes), older adults reported lower De Boer's rating scores (i.e. worse feelings of glare) than their younger counterparts.

This paper describes a new method for objective evaluation of wind noise in the passenger compartment of a car. The loudness and direction of noise in each frequency band can be estimated by performing analyses based on human hearing properties. Therefore, those wind noise components that are annoying to the passengers or those wind noise components whose source location can be determined by the human listener can be identified objectively. Furthermore, the total loudness of wind noise can be estimated quite precisely by adding the loudness of the frequency bands for noise emanating from the direction of the side window.

Since wear resistance and fatigue strength are key requirements for chassis components, induction hardening is widely used to apply compressive stress for controlling crack growth. Therefore, it is crucial that the influence of defects is examined with compressive residual stress applied to parts. In this report, the relationship between crack depth and compressive residual stress is evaluated using a cylindrical specimen and a torsional fatigue test. The test results were found to be consistent with CAE simulations performed in advance. In the future, it will be necessary to make this method applicable to product design to further improve vehicle safety performance.

The use of a head-up display (HUD) system has become popular recently, as it can provide feedback information at a position easily seen by the driver. However, the outline of the HUD bezel often reflects on the windshield of a HUD equipped vehicle. This phenomenon occurs when the sun is at a high position and reflects off the top of the instrument panel and the front view is dark. For this reason, it can occur when driving on asphalt paved roads, causing annoyance to the driver. Under fixed environmental conditions, the vehicle based factors that influence the annoyance caused by reflected boundary lines are the position of the reflection, line thickness, and the contrast of the reflected boundary line. These can be represented by the conspicuity of a striped pattern (contrast sensitivity function). In previous research in 1991, M. S. Banks et al. studied a contrast sensitivity function that included the factors stated above.

We developed new microalloyed steels, containing about 0.05% sulfur, which have excellent as hot-forged toughness even when forged at the temperatures of about 1300°C(2375°F). We also estimated the various properties of the new microalloy steel in the as hot-forged condition, comparing them to quench and tempered SAE1055 steel used in the front axle of a small truck. The results showed the new steel has improved yield strength, fatigue strength, absorbed impact energy and machinability over the SAE1055 steel.