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Various types of tread pattern are designed depending on the usage of tire. However, there are few papers described about the relationship between the shape of tread rubber block and dynamic characteristics. The authors measured the dynamic characteristics of rubber block when it is slid to the various directions. As a result, it is understood that there is the special relation between the shape of block and the sliding direction. Generally, when a material body was slid, the direction of frictional force should correspond to a sliding direction. On the other hand, different results were provided in the case of rubber block. When the shape of block was symmetric toward the sliding direction, the direction of force corresponded to a sliding direction. However, in case of asymmetry, the direction of force did not agree with it, and it is found that the certain tendency was seen in a difference of the direction by the shape.

As the progress is made in vehicle dynamics analysis, tire models for vehicle dynamics analysis that are broadly applicable have been increasingly sought. Therefore, following the previous paper, the method to formulate a tire model consisting of theoretical and experimental equations, that represents, with high accuracy, the experimental characteristics of a tire, based on relatively simple theoretical equations - by obtaining the coefficients through experiments and further adding to them appropriate collections - is investigated in this paper. In the previous paper, the procedure to formulate a model that shows the changes in lateral force, driving-braking force and aligning moment, generated on a tire running at a constant velocity, due to slip angle, slip ratio, camber angle and load was presented. However, the change due to velocity was not taken into consideration.

The evaluation of ‘Maneuvering Feeling’ during driving should not only be judged subjectively by the driver but also judged objectively with scientific results. This paper will detail experiments conducted using two types of driving simulators. For the purpose of obtaining the objective evaluation of the driver's feeling under various driving conditions, specific color photographs were taken of the distribution of his face temperature. These were taken momentarily with an infrared camera. His blood pressure and heart rate also continuously measured his physiological responses. The face temperatures of almost all drivers tended to rise while driving. Especially so, when they encountered unexpected changes in the road environment. This was because of the driving task and stress incurred. There is a correlation between the face temperature, the blood pressure and the heart rate.

Easy-to-use tire models for vehicle dynamics analysis have been studied at various institutions. This paper presents a tire model consisting of theoretical and experimental equations representing the experimental characteristics of tires, by employing relatively simple theoretical equations (1), (2), (3) and (4)*, obtaining their coefficients through experiments, and adding further corrections. As a result, we have obtained a model representing the change of forces and moment generating in the tire, which are caused by slip angle, slip ratio, camber angle and load. This model has many advantages including easy correspondence to physical phenomena, higher possibilities of practical development and a possibility of rational correction of the errors during experiments.

The sudden darting out of a pedestrian or a vehicle onto the road was used as an unexpected situation to investigate the driver's response and behavior with the driving simulator. In this emergency situation, the driving operations to avoid the pedestrian or the crossing vehicle, and the percentage of having an accident depended on the driver's driving experience. Consequently, 55% of the subject drivers operated the steering wheel to avoid the pedestrian. The drivers who applied the brakes to avoid the pedestrian were a little less than 90% among the experienced drivers, but only half of the beginners. When even both the steering and braking were used to move to the other side to avoid the pedestrian, half of the experienced drivers had accidents, and about 65% of all of them had accidents. When the beginners tried to avoid the pedestrian in various ways, almost all of them had accidents.

The authors of the present paper report the measured physiological phenomena of a driver falling into the lowered alertness level and they evaluate the effectiveness of vibration stimulus added to a driver in the low alertness level as a means to keep the driver awake. From the survey test for 21 subjects, it was found the awakening whole-body vibration by the addition of which the alertness level of a driver could be heightened effectively, and it existed in the range between the amplitude of 1 to 15 mm and the frequency of 1 to 4 Hz.

In districts of Japan and other Asian countries where roads are not well developed, densely mixed automobile - bicycle traffic on old narrow roads is usual. According to Japanese statistics 1980, the number o£ fatalities in traffic accidents between bicycles and automobiles surpasses 10 percent of the total and certain measures to decrease this count are requested. In the present report, the authors paid attention to automobiles approaching bicycles from behind and passing by. At first, actual traffic states on narrow roads were recorded by VTR and many dangerous scenes were observed. Then simulative experiments were performed as follows; A narrow road was set with various obstacles e.g. power pole on one side. Several types of bicycles were operated there by subjects under various conditions e.g. passing automobile on the other side.