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The movements of the driver's foot from the accelerator to the brake pedal in normal and emergency braking situations were recorded using VTR (Video Tape Recorder) cameras and then analyzed using the three-dimensional image processing system (Peak Motus). The displacement and velocity of driver's foot motion was also precisely measured by a CCD (Charge Coupled Device) laser displacement sensor. Data of instantaneous velocity and the elapsed time of driver's sole motion immediately after releasing the accelerator pedal were obtained. Using this information, a feasibility study of the braking assistant system was undertaken before application of the brake pedal in an emergency situation.

An aspect of recent human interface concerns suitable and comfortable maneuvering system for drivers. An operation device with a Joy-stick was developed, that was compared with a conventional steering wheel by actual vehicle traveling tests. The vehicle’s motion under slalom travel conditions was filmed by VTR (Video Tape Recorder) cameras and was analyzed using the image processing system. Driver’s heart rate was also measured to examine his mental load while maneuver. An optimum steer angle with respect to an angle of inclination of the Joy-stick by driver’s manipulation was examined using the driving simulator.

We paid attention to the correlations of individual driver’s behavior, the vehicle motion and the road environment, and conducted the travel experiments to investigate the characteristics of the driver’s operation behavior. Driver’s behavior was shot by CCD cameras set in the cabin, and the vehicle motion was simultaneously taken by digital video cameras set on the test course. We analyzed quantitatively the both movements using the three-dimensional image processing system. As the result, driver’s behavior affected by his set up seat position was made clear quantitatively as shown in the moving traces of his body and arms.

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.

To evaluate a driver's task and stress level objectively while maneuvering a vehicle, we paid attention for human's physiological responses under the condition. The eccrine sweat on a palm and a forehead, heart rate and a face temperature of a subject driver were monitored and measured continuously and quantitatively using the specified direct sweat measuring equipment, the electrocardiograph and the infrared thermometer respectively. As a result of having analyzed these data physiologically, we propose that the driver's stress level can be objectively determined by the quantity of eccrine sweat, changes of heart rate and changes of face temperature.

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.

In the large cities of Asian countries, the traffic flow at many intersections is controlled by traffic signals. Most of the vehicles there are obliged to stop or to decrease their mean speed. For the purpose of reducing the fuel consumption of vehicles, the authors paid their attention to the method of passing through a series of traffic signals and carried out the experiments for several traveling modes of the vehicles. As a result, we proposed to the drivers that they drove according to the controlled-traveling-mode which consisted of controlling the speed, the acceleration and the deceleration of the vehicle according to the time interval of each traffic signal. When a driver was forced to run in the controlled-traveling-mode instead of the ordinary- traveling-mode, the fuel consumption of the vehicle improved about 20 percent although the traveling time was the same. The improvement was 10 percent for a group of traveling vehicles.

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.

This study quantitatively analyzed the movement of a driver's upper body in relationship to vehicle motion using Peak Motus, the three-dimensional image processing system. Consequently, this analysis method proved useful and effective in introducing the correlation between driver behavior and vehicle motion with numerical values. It was found that while cornering, the drivers tended to incline their upper bodies to one side against centrifugal force and turn their heads in advance in the direction the vehicle was heading.

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.