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In order to meet increasing demands for safety and comfort in a vehicle compartment, automatic adjustment of seat, mirrors, steering wheel has been developed. The multiplex wiring system was constructed for the automatic adjustment of the cockpit elements to drivers preferred positions or to physique-matched settings based on ergonomic data. This paper describes the construction of the multiplex system and functions of automatic adjustment of the cockpit elements for comfortable driving position and better visibility.

Spray motion visualization, mixture strength measurement, flame spectral analyses and flame behavior observation were performed in order to elucidate the mixture preparation and the combustion processes in Mitsubishi GDI engine. The effects of in-cylinder flow called reverse tumble on the charge stratification were clarified. It preserves the mixture inside the spherical piston cavity, and extends the optimum injection timing range. Mixture strength at the spark plug and at the spark timing can be controlled by changing the injection timing. It was concluded that reverse tumble plays a significant role for extending the freedom of mixing. The characteristics of the stratified charge combustion were clarified through the flame radiation analyses. A first flame front with UV luminescence propagates rapidly and covers all over the combustion chamber at the early stage of combustion.

A study was conducted to obtain basic data on frontal crash deformation of compact cars (mini-sized motor vehicle). A compact car is lighter in weight than the other type of passenger cars due to the category size. In case of a ordinary passenger vehicle to compact car crash, it was assumed that the deformed value which leads to a higher speed as a barrier equivalent velocity becomes bigger than that of a ordinary passenger vehicles. For analyzing a frontal crash characteristics of compact cars, three experimental collisions which compact cars were crashed to a frontal full-lap barrier with velocities of 85 and 100 km/h and half-lap offset barrier with velocity of 85 km/h were performed. This study deals with the process of frontal deformation and the energy absorption diagram of the compact car body, and these are discussed to compare with the publicized data on small passenger vehicles.

Several different steel sheets were tested for energy absorption, using hat square columns and dynamic crash testing. Results indicate that steel sheets containing large volume fraction of retained austenite have relatively high energy absorption. The relationship between retained austenite and energy absorption was analyzed. These special steel sheets have already been successfully used for production body parts, such a front-side-member, without difficulties arising in volume production.

This paper describes the method to improve the energy absorption characteristics during the vehicle frontal collision. The method is to control the collapse phases of the members constituting the vehicle body and to increase collapse force of a member. This phase-control can be accomplished by superimposing the crest of the collapse force curve, which one member causes, on the trough of any other members'. The bulkheads installed in the members are useful. to control the phase and to increase the collapse force. Numerical analysis and experiment of a vehicle collision show that the control leads to the improvement of energy absorption characteristics and load transmission efficiency.

Improvements for pedestrian head protection in a car-pedestrian accident have been discussed in several countries. Test methods for evaluating head protection have been proposed, and most are sub-systems using rigid headforms with or without headskin. In those tests, HIC is used as a criterion for head protection. This paper discusses the test conditions and requirements of the headform impact test. The influence of different test conditions and their importance on head impact test requirements, were verified. The primary items cited are as follows: (1) The results of the rigid headform were similar to that of the human cadaver skull in cases without skull fractures. Consequently, the rigid headform can be used for the impactor simulating a condition without skull fracture. (2) In the cases of HIC≤1000, the force-deformation curves of the hoodtops showed similar characteristics with maximum dynamic deformations over 60mm. (3) Impactor mass affected the maximum acceleration and HIC.

This paper is a compilation of the present state of research in Japan relating to offset frontal crashes using a deformable barrier. It contains an analysis of actual accidents in Japan, accident reproducibility tests implemented using vehicles as examples of representative accidents and a consolidation of the results of studies of reproductive techniques reproduced using a deformable barrier based on the accident reproducibility test results. In the deformable barrier tests, in the case of changes in the offset ratio, barrier face form, barrier face rigidity, crash velocity and the like, the degree of change of vehicle behavior, dummy behavior, vehicle deformation and the dummy injury values have been compared with the results study of accident reproducibility tests. From these results, basic data was obtained relating to test methods for offset deformable barrier collisions.

To investigate the human head impact tolerance in terms of changes in vital functions, a series of head impact experiments was performed using live monkeys, which are morphologically analogous to humans. To find a causal relationship between the impact and changes in vital functions, three kinds of experimental conditions were used: translational acceleration impact and rotational acceleration impact (both using a head restraint mask with broad contact area), and impact of the unrestrained head against a padded flat surface. The results indicated that the concussion, cerebral contusion and skull fracture in the monkeys depended on: i) the translational and rotational acceleration impact; ii) the contact area of the impact; iii) the amplitude and duration of the imposed head acceleration*; iv) the direction of the impact region (whether frontal or occipital).

Road visibility is an important problem in traffic safety. We are developing a computer simulation program to evaluate road visibility with headlamps for night driving. The simulation program under development aims to indicate visually the various changes in visibility. Road visibility changes in a complicated manner due to road alignment and facilities. This paper presents a computer simulation program which can express road alignment and road illuminance in perspective, as the first stage of the project. The features of the simulation program are that it can set up road alignment in accordance with a real road, and that it can set up at any horizontal or vertical alignment and superelevation, and also that it can deal with the shadow zone where the light of headlamps is shut off by guard rails and dazzle protection facilities.