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Flutter is not a simple phenomenon derived from non-linearity of the tire's cornering characteristics or existence of the tire unbalanced mass, but rather is a compound dynamic phenomenon. In the experiment, an interesting beat phenomenon was found, which was derived from the coexistence of forced vibration and self-excited vibrations. Consequently, a deeper understanding was obtained concerning the effect of play and friction on the flutter of steering system. This study explained flutter phenomenon by using mathematical model for driver/vehicle system.

The traffic laws in the People's Republic of China are well established. The present city traffic condition is, however, serious and the rate of traffic accidents is very high. In this study, traffic conflict data in Tianjin are collected and analyzed in order to obtain the basic cues for reducing accidents. On the basis of the results obtained three kinds of countermeasure; improvements of traffic signal systems, passing through methods of bicycles and driving maneuvers of drivers, are proposed.

The skill acquisition process of novice drivers under conditions of steady-state cornering with a rear wheel steering vehicle is compared with the visual and control performance of experienced drivers. After a short-term training session, the vehicle control skills of the novice drivers were considerably improved. The above findings correspond with the results that novice drivers perform with a front wheel steering vehicle. The visual behavior of the novice drivers, however, presented a striking contrast to that of the experienced drivers. The experienced drivers concentrated their eye fixations on the inside of the course, while the novice drivers paid more attention to the vehicle's direction of travel.

The perceptual performance of horizontal space judgment for novice and experienced drivers is investigated. Two of poles were used for the space judgment. The judgment tasks involved the evaluation of three different pole spacings at two separate distances. The drivers were required to judge the possibility of negotiating between the poles. When the drivers were positioned at a long distance from the visual objective, their space judgment between poles was narrower than that when they were positioned at a short distance. When the judgment object was placed at a short distance, the novice drivers tended to judge the space narrower than the experienced drivers. Furthermore, the response time of judgment for the novice drivers whose skill progress speed was slow, became long when the judgment object was placed at a long distance.

Visual and driving behavior of novice and experienced drivers is investigated when they negotiate the vehicle between standing or moving obstructions (pedestrian and vehicle) on both sides. As the driving tasks became difficult, they sampled the right obstruction at a higher rate than the left one regardless of the position of pedestrian or vehicle. However, the novice drivers whose skill acquisition speed was slow tended to increase their fixation rate for the vehicle's direction of travel. With respect to driving behavior, vehicle speed at the meeting point for the novice drivers was faster than that for the experienced drivers. The novice drivers drove on the right obstruction side systematically irrespective of the driving tasks.

The skill acquisition process of novice drivers under conditions of steady-state cornering is compared with the visual and control performance of experienced drivers. After a short-term training session, the cornering speed of the novice drivers was close to that of the experienced drivers. The visual sampling strategies for the experienced drivers were critically concerned with the inside of the course. The novice drivers, however, tended to pay much attention to the outside of the course. In addition, the search and scan patterns for the novice and experienced drivers were different. It was found that the acquisition speed of visual sampling strategies was slower than that of vehicle handling for the novice drivers in the skill acquisition process.

In this study, the obstacle negotiation behavior of novice drivers is investigated under the influence of alcohol. Following results are obtained that the fixation durations for the intoxicated subjects increased in proportion to the blood alcohol concentration levels and the subjects tended to fix intensively on the specific objects for negotiation cues. All subjects exhibited the unusual saccadic movements at the intoxicated conditions.

In this study, the novice driver behavior involved in traffic conflicts is investigated in order to obtain the cues of driver education program for avoiding traffic accidents. Following results are obtained that when the novice drivers encounter the oncoming vehicles, they fixate the vehicles at higher rate than the conflict objects and induce the traffic conflicts. In case of no oncoming vehicles, they also induce the conflicts because their strategies of visual search are critically concerned with the vehicle's direction of travel. They cause other traffic conflicts because it is difficult for them to maintain their vehicle on the correct lane position.

This study investigates the driver/vehicle responses as affected by oncoming vehicles and obstructions. The results showed that in most cases neither the novice drivers nor the experienced ones fixated the oncoming vehicles, but that the drivers anticipated the roadway ahead at great distances, and monitored the oncoming vehicles with peripheral vision. There were no significant differences in the vehicle lateral displacement for the avoidance behavior between the novice and experienced drivers. However, the fixation time for the obstructions was shorter and the completion time of fixations was earlier for the novice drivers as compared to those for the experienced drivers. The strategies of visual search for the novice drivers were critically concerned with the vehicle's direction of travel.

Junior college students of the automotive course are required to get the credits of the automotive engineering in which vehicle performance is instructed. Since no Japanese colleges have test roads, vehicle performance closely related with the lecture of automotive engineering has not been experimented. This paper proposes the education methods in which CAI (computer aided instruction) materials are used. The CAI materials include two examples of the simulation of vehicle performance, the brake test and the power performance test. The instruction programs expand the theoretical equations and display the vehicle performance using the animation and graphics technique. The results show that the CAI materials are able to be substituted for test roads to study the vehicle performance tests.

This study investigates the visual behavior of novice and experienced drivers with three tasks when the stop line disappears from a driver's view before he/she performs a stopping maneuver. The tasks were stopping right in front of the stop line, (a) after traveling in a straight line, (b) after pulling over to the left line, and (c) after pulling over to the right line. The results showed that the range of horizontal fixation locations for the experienced drivers was wider than that for the novice drivers and that the experienced drivers looked closer in front of the car than the novice drivers. These results suggest that the strategies of visual search for the novice drivers were critically concerned with the vehicle's direction of travel under the conditions of high driving tasks.

This study investigates the drivers' visual behavior in obtaining information through door and fender mirror systems. The novice and experienced drivers had no differences in their pattern of eye-head coordination in mirror glance behavior. Both door and fender mirror systems on the right (driver) side appeared to have no differences for the novice and experienced drivers. However, the response time for the left (passenger) door mirror glance of the novice drivers was longer than that of the experienced drivers. This may be attributed to the location of the left door mirror which makes an angle over 70° to the straight ahead of the drivers. Left fender mirror, rather than left door mirror, would be recommended for the novice drivers.

This study investigates the drivers' visual behavior that occurs under conditions of obstacle avoidance with normal and restricted viewing. In the normal viewing, the experienced drivers concentrated on the visual objectives for obstacle avoidance, while the novice drivers sampled the direction of travel quite frequently. In the restricted viewing, the male novice drivers under 20 initiated the compensating visual behavior, but the female novice drivers over 30 displayed the same or a regressive tendency compared with normal viewing. The experienced drivers scanned the obstructions closer in front of the vehicle than the novice drivers in order to increase their intake of visual information.

A new and simple technique of simultaneous measurements was developed to investigate changes in drivers’ eye fixations. Using an eye marker system and reference targets mounted on the front bumper of a vehicle, the visual behavior of novice drivers was compared with that of experienced drivers to find visual cues of skillful handling. It was found that the increase in horizontal angular displacement of fixations is approximately linear with the increase in the head displacement. Coefficient of determination for the novice groups is smaller than that for the experienced groups. Vertical angular displacement of fixations was almost the same for both the novice and experienced drivers, but head displacement for the novice drivers was the head-up type and that of the experienced drivers was the general or direct type.