SEISAN KENKYU
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Volume 66 , Issue 2
Showing 1-30 articles out of 30 articles from the selected issue
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Special Section ITS World Congress Tokyo 2013
Introduction to Special Section
Research Review
  • Mostafa KAMALI, Shintaro ONO, Katsushi IKEUCHI
    Volume 66 (2014) Issue 2 Pages 87-94
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    We propose a method for detecting and stabilizing shaky frames of omnidirectional videos captured by omnidirectional camera systems mounted on top a car. We introduce a technique to detect frames where the video has unwanted shakes and jitters. This enables us to avoid stabilizing all frames of the video that can be very time-consuming in long videos. The main difference between two consecutive frames, specially when the video is shaky, is caused by camera rotation. We decouple rotation and translation and compensate only for rotation. We use a fast and robust method to estimate the camera rotation between two consecutive spherical frames. Our method uses only two pairs of corresponding points as seeds in RANSAC that makes the computation faster than other methods. Our experiments show that our results are comparable to those methods that compensate for both rotation and translation but our method is faster and more robust.
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  • Kohei KOIDE, Kenichi ISHINAZAKA, Masahide SASAKI, Takashi OGUCHI Takes ...
    Volume 66 (2014) Issue 2 Pages 95-100
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    Japanese ITS advancements have greatly contributed to the solution of road traffic problems such as traffic accidents and congestion. The success of ITS is a product of governmental initiative and cooperative relationships between the industrial,governmental, and academic sectors. Their efforts have popularized in-vehicle units of Japanese mission critical systems over the last twenty years, with the result that the car navigation systems, Vehicle Information Communication System (VICS) and Electronic Toll Collection system (ETC) have been put to use in over 30 million and 50 million vehicles,respectively.As well, ITS has become of major importance in government road traffic policies.
    We think that the future direction which Japanese ITS should aim at is not only enriching Japanese mission critical systems, but also realizing sustainable traffic society in local cities. For that purpose, we think it important to make a mechanism in which citizens can customize ITS according to their needs and the administration needs of local cities.
    This paper proposes two kinds of ITS promotion measures for the advancement of future Japanese ITS. One is measures which use ITS more effectively in governmental ITS strategies and policies. Another is measures which promote the introduction and practical implementation of ITS smoothly in local cities.
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  • Ashwani KUMAR, Yoshihiro SATO, Takeshi OISHI, Shintaro ONO, Katsushi I ...
    Volume 66 (2014) Issue 2 Pages 101-107
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    For 3D modeling of urban structures in world coordinate system using GPS, the position accuracy is of- ten degraded due to multipath signals and reflection of signals from the surrounding buildings. Multipath signals can be identified and mitigated by measuring power of received signals. However, reflected signals which are not accompanied by direct signals can not be identified using signal power measurement. In this paper, we propose a method to identify reflected signals using range data and exclude such signals from position calculation using weighted non-linear solution by trilateration. Large improvements in position accuracy obtained in urban scenario verify the proposed method. We reconstructed 3D models of large scale buildings using improved GPS positions. Experiments results show that the proposed method works effectively in urban scenario.
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  • Shunsuke MIURA, Shoma HISAKA, Shunsuke KAMIJO
    Volume 66 (2014) Issue 2 Pages 109-115
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    Global Navigation Satellite Systems (GNSSs) suffers from multipath effect in urban canyons. Many approaches have been employed to eliminate multipath signals in order to reduce positioning errors. Among these, ideas that consider surrounding buildings to evaluate possible multipath have gained most interest. However, such approaches, although successful, require many satellites after eliminating multipath signals. This study proposes an approach in which the multipaths themselves are used for positioning error correction. The proposed algorithm evaluates the pseudoranges of the possible multipath signals by referring to the building geometry. The proposed method was verified through field experiments in urban canyons in Tokyo.
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  • Hiromasa NIIMI, Naohisa AOKI, Shunsuke KAMIJO
    Volume 66 (2014) Issue 2 Pages 117-123
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    In order to solve the congestion problems in urban road network, we would like to propose an algorithm to optimize offset value of each intersection by considering boundary conditions of offset values at adjacent intersections and platoons. A proposed algorithm maximizes the overlap of green-time among adjacent intersections where traveling time of each link should be considered to estimate the green-time overlap and to predict platoons. Traffic simulations were performed using VISSIM, and the proposed algorithm was proved to improve the traffic efficiency. In this paper, simulations were done in the conditions of under-saturated traffics.
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  • Kazuma FUKUMOTO, Hiroshi KAWASAKI, Shintaro ONO, Hiroshi KOYASU, Katsu ...
    Volume 66 (2014) Issue 2 Pages 125-132
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    Recently, a number of researches are conducted to construct the actual city into computers for the purpose of web services, ITS, disaster analysis, landscape simulations and so on. Further, with the spread of on-vehicle video cameras, it becomes common to share the on-vehicle video on website. If locations of the videos are available, the data can be efficiently used for virtual city construction. In this paper, we propose a method to realize localization of anonymous on-vehicle videos uploaded on the web by using video matching technique with Temporal Height Image (THI), Affine SIFT and Bag of Feature (BoF). THI retains information of relative building heights from temporal image sequences and the Affine SIFT realizes a robust matching for variance of both camera speed and driving lane. Finally, BoF representation allows us to realize a stable matching with less computational cost. We conducted several experiments using real image sequences of the actual city to show the successful results of the proposed method.
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  • Katsushi IKEUCHI, Masao KUWAHARA, Takashi OGUCHI, Shintaro ONO, Takesh ...
    Volume 66 (2014) Issue 2 Pages 133-139
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    For reducing CO2 emissions from road traffic, general citizens as well as drivers and industries should perform eco-friendly travel behavior. We are going to realize this by distributing and presenting the "Regional Transport Information" for citizens, using information and communication technologies - traffic situations at some spots are observed by monitoring cameras and probe information, the situation of the whole area is estimated by interpolating them, the amount of CO2 emission is calculated, and visualized and displayed through information devices. Field operation tests are also performed in Kashiwa City to explore acceptance and effectiveness of the system. This document reports the detail of the system and intermediate result of the experiment.
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  • Shinichi SAKAMOTO, Sakae YOKOYAMA
    Volume 66 (2014) Issue 2 Pages 141-146
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    Road traffic noise is one of serious impacts which are generated from road network. In order to keep moderate sound environment in crowded and busy cities, noise mitigation measures are important. In Japan, advanced noise control technologies have been developed on basis of experience of serious pollution issues in 1960s and 1970s. In this report, noise control technologies developing in Japan is firstly described and advanced researches on noise reduction and noise prediction against road traffic will be introduced.
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  • Ayumi HAN, Shintaro ONO, Katsushi IKEUCHI, Yoshihiro SUDA, Masato SASA ...
    Volume 66 (2014) Issue 2 Pages 147-154
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    The innovative road marking ‘Optical Dot System’ (ODS) was conceived through the ‘Sequence Design’ (SD) project for driving environment improvement, seeking a new approach of the measures for safety in Metropolitan Expressways (MEX) in 2006. In this paper we attempt to report the circumstances of ODS development including the experiments and evaluations. ODS has been installed on a two lane highway in MEX, at the section of vertical alignment beyond the junction, where 60% of total traffic exceeded the speed limit.
    Soon after the installation, a speed reduction was observed in high speed traffics areas with a downward grade, especially in the nighttime. The shift showed a nearly 20% decrease from the high range (100-120km/h) to the mid-range (80-100km/h). In parallel, we performed the subject experiment at the laboratory in Univ. of Tokyo (UT) to evaluate the direct impact of ODS to drivers’ perception and behavior by using the Driving Simulator3) to generate Virtual Reality of the highway. The experimental results supported the hypothesis that driving was controlled by ODS. After four years of the installation in MEX, we analyzed the collected data in the section of ODS to verify the transition for six years (incl. two years data before the installation). The resulting trend in speed reduction has been maintained through the four years. The sustainable long term effectiveness of ODS has been proven.
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  • Ayumi HAN, Shintaro ONO, Katsushi IKEUCHI, Masato SASAKI
    Volume 66 (2014) Issue 2 Pages 155-160
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    The ‘Optical Dot System’ (ODS), originally developed by the principal author, is a ‘Sequence Design’ (SD) to improve vehicle safety by controlling the speed with a layout of oval-shaped road markings for highway and rural roads. The long lasting effectiveness has been proven for cars, as cited in previous research in 2012. However, in shared roads, the frequent occurrences of bicycle accidents involving pedestrians are a serious issue. In Japan the ownership rate of bicycles is one in 1.5 persons (2007); this is quite high compared to the ownership level in the Netherlands and Germany. In order to address this problem, ODS was resized to be adopted for bicycles. In this research, we performed the subject test at an actual site with cyclists, cycling a downward grade in vertical alignment on a long bridge. The test section was composed of three different road markings: ‘ODS/large’, ‘ODS/small’, ‘traversal line’, with ‘plain’; no markings, as the comparison criteria. The results showed that the cycling speeds on ODS sections were significantly decreased, while, the ‘traversal line’ had no speed control effect, as was the case with the ‘plain’ road. The subjects were instructed to cycle at pleasant, smooth speed, but they were not aware of being controlled by ODS. Significant effectiveness of ODS was proven for autonomously controlling bicycle speed.
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  • Shoma HISAKA, Shunsuke MIURA, Shunsuke KAMIJO
    Volume 66 (2014) Issue 2 Pages 161-167
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    We have proposed a dedicated onboard“ sensor” system utilizing wireless communication devices for surveillance of road users in terms of collision avoidance. Our“ sensor” system estimates the positions of transmitters on road users by comparing the strengths of communications signals of ZigBee devices. According to our experimental results, our system has competitiveness to the system utilizes TDOA localization such as GNSS, at the point of robustness against multipaths in urban canyon. Moreover, our system thought to be capable of detecting road users in non line-of-sight area whom the vision sensors cannot observe. Therefore the system is promising as a composition element of a sensor fusion system for road safety, is the final target. In this work, we report about field operational experiments at real intersections. In experiments at real intersections, we tested the localization ability of our system and GNSS. The proposed system successfully detected the near pedestrians.
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  • Zhipeng WANG, Masataka KAGESAWA, Shintaro ONO, Atsuhiko BANNO , Takesh ...
    Volume 66 (2014) Issue 2 Pages 169-171
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    Vehicle positioning is of great importance to driving assistance and vehicles’ navigation. In tunnel environment, positioning is challenging, since neither GPS sensors nor ordinary cameras function properly. In this paper, we propose a real-time solution for positioning of vehicles. In tunnels, we can gain the absolute coordinates of some specific objects, here the emergency telephone indicators, which are some special lights. Then during the travelling in tunnels, we sense the environment using infrared cameras and detect the emergency telephone indicators to infer the experimental vehicle’s position. In our detection method, we make use of both the emergency telephone indicators’ appearance information and motion information. Through well balancing the pipeline, by making time-consuming steps deal with fewer instances, we gain a real-time detection method with promising detection results.
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  • Hiromitsu ISHIKO, Kimihiko NAKANO, Rencheng ZHENG, Kenji HAGITA, Makot ...
    Volume 66 (2014) Issue 2 Pages 173-178
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    A car navigation system by a smart phone is newly developed, and it is expected that the navigation system can give more convenient and assistant information to drivers. However, sometimes the navigation system may become disturbance to the drivers, and cause distraction during driving, which may result in a traffic accident. Therefore it is an urgent work to evaluate safety of the car navigation system by a smart phone. A car navigation system was integrated into an advanced driving simulator, where the car navigation system can be utilized during driving for studying drivers’ behaviors. The driving experiment was successfully completed by changing the position and size of the display of the navigation system, and driver’s behaviors were recorded. The experimental results indicated that safety of the car navigation system can be evaluated by using the driving simulator.
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  • Sungjoon HONG, Shigeyuki YAMABE, Takashi OGUCHI, Yoshihiro SUDA
    Volume 66 (2014) Issue 2 Pages 179-185
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    To mitigate the traffic congestion at merging sections in urban expressway networks, a dynamic lane operation is being studied in Japan, which dynamically switches one lane to either approach of a merging section with more traffic demand. To evaluate the safety concern, the lane-change behavior when one lane is closed by variable barrier that is informed by variable message sign (VMS) is analyzed in this study. A driving simulation experiment is conducted for the analysis considering the implementation of the dynamic lane operation for merging sections at Route C1 of Tokyo Metropolitan Expressway. Traffic condition and the distance between a lane-closure point and the VMS are considered as critical factors affecting the risky behavior, and their influence on the lane change behavior is studied.
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  • Takahiro TSUBOTA, Ashish BHASKAR, Edward CHUNG
    Volume 66 (2014) Issue 2 Pages 187-192
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    This research aims to develop a reliable density estimation method for signalised arterials based on cumulative counts from upstream and downstream detectors. Although traffic density is a key variable for analysing network performance, its estimation is still challenging due to counting errors associated with urban arterials with mid-link sinks and sources. In order to overcome the issue, CUmulative plots and Probe Integration for Travel timE estimation (CUPRITE) is expanded for density estimation. CUPRITE reduces or cancels the counting inconsistencies when vehicles’ conservation is not satisfied within a section by utilising probe vehicles’ samples. The method is tested in a controlled environment, and the authors demonstrate the effectiveness of CUPRITE for density estimation in a signalised section.
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  • Daisuke OSHIMA, Shinji TANAKA, Tomoyoshi SHIRAISHI, Tadashi KOMIYA, H ...
    Volume 66 (2014) Issue 2 Pages 193-198
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    As global warming has become a major issue in recent years, there is much demand for reliable methodologies to estimate CO2 emission volume from vehicle traffic, using traffic simulation models and emission models. To gain international acceptance for an evaluation result of CO2 emission using a simulation model, the Energy ITS Project proposed a framework for validation of traffic simulation models and CO2 emission models, and reached a consensus through international discussion.
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  • Hisatomo HANABUSA, Masato KOBAYASHI, Katsuaki KOIDE, Ryota HORIGUCHI, ...
    Volume 66 (2014) Issue 2 Pages 199-203
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    This paper describes the development of an on-line traffic simulation system called the “Nowcast Traffic Simulation System” for road traffic in urban areas. The system can reproduce the traffic situation based on various types of traffic data provided in real time such as floating car data and traffic sensor data. The output data is used for several traffic information services, including CO2 monitoring. In this paper, we explain the concept of the Nowcast Traffic Simulation System and its theoretical framework followed by an example of a demonstration experiment in Kashiwa City in Japan.
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  • Tawin TIRATANAPAKHOM, Takashi OGUCHI, Shinji TANAKA, Sungjoon HONG, Hi ...
    Volume 66 (2014) Issue 2 Pages 205-209
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    The analyses of route choice behavior based on revealed preference (RP) data are rare because of the difficulty of observing route choice decisions in practice. On Tokyo metropolitan expressway, traffic surveillance and electronic toll collection (ETC) systems provide rich sources of traffic condition and behavior data. This paper analyzes route choice and route switching behavior using the observed route choice decisions collected from ETC data in the selected study area. Moreover, the paper identifies and evaluates the importance of attributes relating to traffic condition information and drivers’ traveling characteristics derived from both ETC and detector data.
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  • Haruhisa AKATSUKA, Takashi OGUCHI, Daisuke OSHIMA, Sungjoon HONG, Hisa ...
    Volume 66 (2014) Issue 2 Pages 211-214
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    There are several problems that should be solved in order to raise the penetration rate of electric vehicle (EV). One problem is the short cruising distance that makes EVs frequently recharged. Long recharge time is another problem. However, it is believed that EVs can contribute to the conservation of energy and environment. This study aims at analysing the actual recharging behavior by traffic simulation and optimizing the placement of recharging stations. To take into account the electricity consumption of EVs in the simulation, trip chains of each EV are estimated from existing Origin-Destination volume data and the simulation model is customized. The study area is the inside of Ring Route 8 in Metropolitan Tokyo and its vicinity, Japan. This study also examines the potential congestion caused by recharging behaviour of EV.
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  • Yoshihiro SUDA, Kimihiko NAKANO, Takayuki HIRASAWA, Hidenori YOSHIDA, ...
    Volume 66 (2014) Issue 2 Pages 215-218
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    This paper introduces the contents of field operation tests (FOT) of an innovative advanced safety vehicle (ASV) services scheduled to be demonstrated by the Hiroshima ITS promotion council. The proposing services are realized by vehicle-to vehicle (V2V) communications between private cars and public transport vehicles, using dedicated on-board units on both vehicles and which premises the usage of ITS-dedicated radio frequency band. The images of developing services for the ITSWC2013 post congress tour between a tramcar and a private car have been described.
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  • Hiroki NAKAMURA, Kimihiko NAKANO, Rencheng ZHENG, Masanori OHORI
    Volume 66 (2014) Issue 2 Pages 219-223
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    Advanced driver assistance systems need to be made adaptive to changes in driver conditions to improve their performance. To achieve this, we require accurate, non-invasive estimates of driver neuromuscular admittance. Previous research has shown correlation between driver grip strength and driver stress and correlation between human neuromuscular admittance and grip strength. Hence, neuromuscular admittance can be estimated for the non-invasive estimation of driver stress. In this research, a method of measuring neuromuscular admittance using sensors of a power steering system is proposed and its performance is examined in an experiment using a driving simulator. Neuromuscular admittance is estimated from the measured feedback torque of the power steering and steering wheel angle, and the feasibility of the system is shown in the case of highway entrance and passing situations.
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  • Toshiyuki SUGIMACHI, Takanori FUKAO, Takuma ARIO, Yoshitada SUZUKI, Hi ...
    Volume 66 (2014) Issue 2 Pages 225-230
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    In Japan, a new project for reducing CO2, called "Energy ITS project" has started since 2008 by New Energy and Industrial Technology Development Organization (NEDO) for reducing CO2 emissions. This project aims to develop techniques for the autonomous platooning of heavy-duty trucks to reduce their air resistance in expressway driving. Platooning needs lateral and longitudinal control. This paper describes novel lateral and longitudinal control. Lateral control method is based on path following. Longitudinal control method uses information acquired from the front and rear trucks by inter-vehicle communication. And a steering control methods using feedfoward control to deal with a road cant and a deviation from a target course by a disturbance are proposed. The experimental results of autonomous platooning are provided to evaluate the effectiveness of the method. In this experiment, the platoon is composed of four trucks, and two kind trucks are used.
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  • Seungyong LEE, Kimihiko NAKANO, Masanori OHORI, Masahiko AKI
    Volume 66 (2014) Issue 2 Pages 231-236
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    Automatic platooning is an advanced traffic system aimed at solving environmental and traffic problems in the transportation field. Identifying accurate parameters for vehicle control in any driving conditions can guarantee high performance in automatic platooning. In this study, an identification method is proposed for the yaw moment of inertia that is essential parameter for the steering control. The performance of the proposed estimation method was evaluated through experiments using GPS measurement system with two different road conditions, one on a straight flat road and the other on a banked curved road. The validity of the proposed identification method using GPS measurement system was verified by comparing the measured yaw moments of inertia on the banked curved road condition.
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  • Masahiko AKI, Teerapat ROJANAARPA, Kimihiko NAKANO, Yoshihiro SUDA, To ...
    Volume 66 (2014) Issue 2 Pages 237-243
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    This paper deals with a feasibility study of an ECU and sensor systems for automatic driving of a heavy-duty vehicle. The energy-saving ITS project has been researching for the automatic platoon driving of heavy-duty vehicles using an ECU and several sensing systems which were a camera / a laser radar lane marking recognition system and a road surface recognition system . In this research, a usability of the sensing system was examined by a long term measurement and a practical logistic environment. An evaluation of the ECU and the sensing systems were carried out during work on an actual logistic truck.
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  • Masahiko AKI, Kimihiko NAKANO, Yoshihiro SUDA, Yoshitada SUZUKI, Hirok ...
    Volume 66 (2014) Issue 2 Pages 245-248
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    This paper deals with development of a back-up brake system for improvement safety of brake systems in the energy-saving ITS project. In former development, a redundant brake system had parallel placed with a main brake system for keeping a safety in automatic platooning experiment. However, these main and redundant brake systems have the same-type EBS computer. In this paper, mechanical brake as a third brake system is developed by mechanical type system for safety improvement in automatic platooning experiments. Moreover, braking experiment using the heavy-duty vehicle was carried out. From the experimental results, a possibility of a practical use of the mechanical brake system was revealed for the automatic driving of the heavy-duty vehicle.
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  • Rencheng ZHENG, Kimihiko NAKANO, Shigeyuki YAMABE, Yoshihiro SUDA
    Volume 66 (2014) Issue 2 Pages 249-251
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    In Energy-Saving ITS Technology Project of Japan, a reliable automatic platooning of trucks is a main objective in highway transportation. The application of a driving simulator is useful to evaluate driving safety of the automatic platooning, and thus a new truck driving simulator was constructed to reproduce truck dynamics and control. A full-scale cabin of truck was integrated into the driving simulator. And a gap distance controller for longitudinal and lateral directions was designed for the automatic platooning. On the assumption of system failures in the processes of formation of the automatic platooning, driver behaviors for the emergency avoidance in a following truck were studied in the driving experiment using the truck driving simulator.
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  • ZRencheng ZHENG, Kimihiko NAKANO, Shigeyuki YAMABE, Takeki OGITSU, Shi ...
    Volume 66 (2014) Issue 2 Pages 253-257
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    A cooperative adaptive cruise control (CACC) system enables shorter gaps and tighter control of gaps using vehicle-vehicle communication, and the CACC system has significant positive effects on traffic flow in highway system. The study is about an applicable evaluation of human machine interface (HMI) for CACC of trucks using a truck driving simulator (DS) system. A novel truck DS was constructed to reproduce truck dynamics and control by integrating a full-scale cabin of truck into a universal DS system. And a gap distance controller for longitudinal and lateral directions was designed to realize the CACC of trucks. A HMI system prepared for the actual-vehicle CACC driving was used for examine the driver’s acceptance, which is mainly about whether the HMI help driver to realize safe and comfortable CACC driving when the HMI system real-time provides the advanced information service.
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Research Paper
Research Flash
  • Tadashi MASUOKA, Yutaka TOI, Taiichi NAGATA, Hideshi KAGAWA, Hirohide ...
    Volume 66 (2014) Issue 2 Pages 259-262
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    The elasto-viscoplastic constitutive equation based on the concept of continuum damage mechanics was formulated for the niobium alloy (C103) which was used as a thruster chamber material in a satellite. Fatigue life analysis based on damage mechanics was conducted to simulate the experimental data obtained by the strain controlled fatigue tests using round bar specimens made of the niobium alloy. Lots of material parameters in the constitutive equation are determined based on the experimental data. Stress-Strain curves and damage value evolutions were also evaluated and the validity of material parameters was illustrated by comparing calculated values with test results.
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  • Hideaki UEDA, Masanori OKA, Yutaka TOI
    Volume 66 (2014) Issue 2 Pages 263-266
    Released: March 31, 2014
    JOURNALS FREE ACCESS
    Heat treatment analysis has been studied by many researchers, and it is utilized to derive the appropriate heat treatment conditions. However, it is not fully tested and supported over the progress of the phase transformation. Especially, the Bainite transformation is classified as intermediate type transformation in general. However, it is almost treated as a diffusive transformation like the ferrite-pearlite transformation and used the KJMA formula to predict the transformation progress. So, in many cases, the amount of the Bainite generation after heat treatment deviates from the experimental results. In this study, we aim to find the problems about the traditional method, and extend the formula of the phase transformation. By comparing with the experimental results, we evaluate the usefulness of the present study.
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