About 40% of the outbreak factor of the traffic jam in the expressway in Japan is the speed reductions of a sag part and the uphill slope, and traffic jam cancellation in the sag part is an important problem. As for the traffic jam measures, construction and development of the reporting from the car navigation system with the soft aspect and the automatic driving to increase the traffic capacity with the hard aspect are performed. However, it takes cost and time so that they spread. In this study, we investigated road-marking measures that are effective for speed recovery in the highway sag by driving simulator experiments, targeting road markings that the driver is watching. As a result, the following two plans were found to be effective. A plan that changes the pitch of the arrow mark from dense to sparse for the purpose of enhancing the feeling of deceleration, and a plan that directly indicates “uphill” or “speed recovery” in letters.
The total number of fatalities in traffic accidents in Japan is decreasing due to the spread of traffic safety measures and the development of safety equipment for automobiles. However, there are still many fatalities in traffic accidents while riding automobiles. In this study, we conducted a demonstration experiment of traffic safety measures in the vicinity of an intersection with a high risk of rear-end collision, which has a slope and a curve just before the intersection, verified the prior and subsequent changes in the vehicle speed and driving position due to the introduction of rubber poles. As a result, the average speed of the car decreased by 2.5km / h at the straight part and 3.5km / h at the curve introduction part. In terms of vehicle type, the speed of the straight part of small cars / normal cars decreased by about 5.0km / h. In addition, the driving position is about 30 cm away from the central lane among all types. As a result of the difference between the average values of the speed before and after each driving position, the average speed was greatly reduced.
Currently, the introduction of LRT is being promoted in Utsunomiya City, but there is a concern about confusion centered on drivers who are unfamiliar after the introduction because it is a completely new model. For this reason, it is necessary to know in advance the driving rules and behavior of LRT. Therefore, we developed a 3DVR content that allows users to view the driving environment unique to orbital traffic on a head-mounted display, using the Haga / Utsunomiya LRT introduction plan as a case study. A questionnaire survey was conducted before and after each of the mainstream CG video and 3DVR contents, and the PR effects and changes in awareness of citizen drivers for each content were quantitatively evaluated. As a result, it was found that citizen PR using each content is effective in reducing the driver's anxiety because it can realistically experience the driving image of LRT. In addition, 3DVR was found to be more immersive than CG video and more effective for alerting while driving.
Both-way running of bicycles, which is commonly seen in Japan, but unique system in the world, has been focused on as serious safety problems at junctions and so on. In Kanazawa city, bicycle lanes in residential streets, which promote bicycles running on left side of the carriageway, have been introduced to solve this problem, and on-street instruction campaigns have been intensively carrying out. As a result, it was found that bicycle accidents decreased on the streets with bicycle lanes and in the districts of area-wide implemented of lanes. The aim of this study is to confirm the special spreading effects of bicycle behavior of left side running on the streets along the bicycle lane streets by the implementation of area-wide bicycle lane system. By employing Generalized Linear Models (GLM) the ratios of left side running of bicycles are statistically significant on the streets along the bicycle lane streets as well.
In this study, we tried to clarify the cause of speed reduction in non-congested condition and the factors that can determine whether or not traffic congestion will occur for three lane section of expressway. Using traffic flow survey results from image observation, we drew speed transition diagrams to find candidate factors for speed reduction. Then we performed multiple regression analysis to verify whether candidate factors have significant effects on speed reduction in non-congested condition. After that, we verified factors that can determine whether congestion occurred or not by discriminant analysis, keeping in mind that the number of data in congested and non-congested conditions differs greatly. As a result, it was suggested that biased lane utilization to right lane, large vehicles, velocity variance and formation of vehicle platoon affect speed reduction. When transitioning from non-congested to congested condition, left lane will begin to be used, and right lane utilization rate will be relatively low, so it was suggested that lane utilization and speed leveling occur.
Examining the cause of car horns can lead to improvement of environmental problems, road structure and operation in car traffic. In this study, in order to evaluate the laws, regulations, road structure and operation methods on automobile, we selected a different country form Japan, Taiwan, investigated the occurrence of the horn with traffic conditions at intersections in Taipei city, and analyzed them from several viewpoints. First, we grasped the relationship between the total traffic volume and the number of the horns. After that, we picked up one of patterns of “vehicle interruption to other”, and analyzed this pattern to find out influential factors to cause the horn under the traffic conditions. As a result, from the first part, the number of horns generated increases in a certain traffic volume range. In the second part, it was shown that the horn occurrence rate on “vehicle interruption” is affected by the speed gap between two cars and interrupt direction of maneuvering car.
Real time traffic condition prediction enables travelers to make smart decisions about departure time to avoid congestion on highway. In recent years, it has become possible to obtain a variety of observation data for traffic condition, so data-driven methods are continuously being developed. The Electronic Toll Collection System 2.0 (ETC2.0) is an example of a data collection system that gathers traffic conditions such as vehicle position, vehicle speed and time information in a wide area network, among others. While this ETC2.0 data can provide us useful information, it is relatively sparse. It is desirable to accurately predict traffic conditions from sparse real data. In this research, the short-term prediction of speed contour map and travel time are performed by the pattern matching of the spatiotemporal traffic state with the ETC2.0 data. Specifically, we use the ETC2.0 probe data and show that the method we used can predict speed contour map and travel time even with sparse data.
The Japanese government and the Trucking Association have set the target number of fatal accidents per 10,000 trucks at 1.5, aiming for the safest transportation in the world. The trucking offices have been required to reform work styles and improve productivity. Among them, more efficient and effective measures must be taken to reach the safest level in the world. Therefore, in this study, we tried to extract factors that affect traffic accident experience using multiple data created in daily work. Consequently, we extracted the factors, including age, continuous running time, operation time zone, and the number of overspeeds, which are related to traffic accidents. In the future, we will aim to improve the accuracy of analysis and necessarily expand the collected data. If these problems can be solved, the existing data will be used to clarify about accidental factors to drivers, who should strengthen their guidance and improve the working environment.
In recent years, the number of accidents on residential roads in Japan has been slowing down. Among them, the number of deaths while walking and riding on bicycles accounted for about half, and these elderly and pedestrians are vulnerable. The occurrence of an accident is a serious problem. In contrast, the Public-Private ITS Concept 2017 is expected to prevent accidents by promoting the spread of autonomous driving. Therefore, in this study, when a conventional vehicle is replaced by an advanced safety vehicle, an analysis is performed using accidents that have occurred in order to construct a collision avoidance model for judging the effect of reducing accidents by automatic driving technology. It was. As a result, while the use of advanced safety automatic vehicles on local roads has confirmed the possibility of accident prevention, there are some accidents that are difficult to prevent with vehicles alone. It was found that it was necessary to consider measures to deal with the situation.
In the earthquake directly under the Tokyo metropolitan area that is expected to occur in the future, there is a concern about collision accidents and road blockages caused by the driver's steering wheel and brake operation due to the earthquake motion at the time of the disaster. In particular, on highways that run at high speed and high density near the epicenter, it is necessary to examine damage assumptions and countermeasures that take into account the driver's driving behavior during an earthquake. However, the driving behavior at the time of an earthquake is still in a situation where sufficient knowledge has not been obtained due to the difficulty of observation, and further elucidation is required. In this study, we obtained driving behavior data assuming an earthquake during indoor running experiments using DS. As a result, it was suggested that the deceleration behavior differs depending on the timing of the information provision on the earthquake early warning, and that the driver with less frequent driving tends to take a unique deceleration behavior during an earthquake.
Recently, with the increase in the number of foreign visitors to Japan, various efforts have been promoted by National Police Agency, Ministry of Land, Infrastructure, Transport and Tourism and private business operators to prevent accidents caused by the rapidly increasing use of foreign car rentals．In addition, urgent safety measures are required, but the cause has not been identified, so it has not been linked to specific measures. In this study, we compared the steep braking point between residents, japanese visitors and foreign visitors (residence: Taiwan, Korea, Hong Kong) to Japan using ETC2.0 probe data on the main island of Okinawa. As a result, the existing method for identifying accident risk points identified sections that were dangerous for foreign drivers visiting Japan, which are likely to be overlooked. The road traffic environment in this section was compared, and the relationship between steep braking by foreign visitors to Japan and the road traffic environment was clarified.