著者

大北 由紀子 菅沢 深 毛利 宏

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.854, pp.17-00085-17-00085, 2017 (Released:2017-10-25)

参考文献数

9

被引用文献数

2

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It has been well known that the drivers' looking aside behavior is one of the cause of traffic accidents. However, it is difficult to investigate the causal relationship between the looking aside and accident. The authors analyzed the features of drivers' looking aside behavior by using the drive recorder data. It is found that this behavior occurs when three conditions stated below are satisfied. The first one is that the time headway is long enough. The second one is that the required deceleration for collision avoidance is supposed to be small. The third is that there is enough time for the drivers to push brake pedal and stop the car safely. Drivers' looking aside behavior under dangerous situation doesn't always lead to an accident, but when the looking aside period is too long, this behavior tends to cause an accident. In addition to the above, it is found that in the low speed range, drivers try to keep a constant headway distance. The mechanism of this trend is clarified.

著者

小山 陸 毛利 宏 風間 恵介 塩澤 裕樹 今村 政道 柏村 聡

出版者

公益社団法人 自動車技術会

雑誌

自動車技術会論文集 (ISSN:02878321)

巻号頁・発行日

vol.51, no.5, pp.785-788, 2020 (Released:2020-08-28)

参考文献数

5

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車体スリップ角推定手法を新たに提案する.本手法では車体前後方向,及び横方向の加速度センサ信号に加え車輪速センサ信号を用いる.提案手法では積分器を必要とせず,信号の代数演算のみで車体スリップ角の推定が可能である.実車実験で取得した信号を用いて,提案手法が従来手法に比べて正しく推定出来ることを示した.

著者

古性 裕之 毛利 宏

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.856, pp.17-00203-17-00203, 2017 (Released:2017-12-25)

参考文献数

14

被引用文献数

1

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We propose curve contour detection algorithm for road white line detection based on Helmholtz principle. White line detection is widely used in driver support systems used mainly in highway or major arterial road. As the common road will be the target of operational area for autonomous vehicle, it is thought to be necessary to develop a new detection algorithm that can deal with various types of road. This paper proposes model-less algorithm that is constructed on a new edge feature inspired by Helmholtz principle through the analysis of the limit of Hough transform. This feature is basically same as Hough defined feature of edge count on the line except two remarkable points. The one is the restriction of count area and the other is the way of count which affords to detect curve line as well as straight line. Implementation by convolutional neural network is explained and the relation between tunable parameters and the detection performance as well as the processing time are discussed. Comparison between conventional methods such as Hough transform or machine learned contour detection algorithm BEL is explained for test image and images taken by on-board camera to show the superiority of proposed algorithm. We demonstrate that proposed algorithm that can apply to diverse road environments but is hardly affected by noise can be realized.

著者

古性 裕之 毛利 宏

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.854, pp.17-00095-17-00095, 2017 (Released:2017-10-25)

参考文献数

14

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We propose image processing method for road white-line detection using brightness gradient direction of edges. Many methods for white-line detection have been proposed for standardized roads. These methods use model fitting for the detection of edges on white-line contour. So it is difficult to apply these methods to non-standardized roads for which modeling is difficult. To expand the scope of white-line detection to common roads in the future, it is necessary to achieve processing without models. Clustering based on position proximity of edges is one approach. However, there is concern about degrading noise reduction that has so far been done by model fitting. In this study, we developed an edge clustering method that utilizes the characteristics of edges on white-line contours; proximity of position as well as proximity of brightness gradient direction. In the proposed method, edges are first clustered based on proximity of gradient direction. And for each cluster, edges are again clustered based on proximity of position. Edge filter bank is specially designed for the first clustering and the effectiveness compared to conventional filter bank is explained. By applying the method to the images taken by on-board camera, we demonstrate that white-line detection that can apply to diverse road environments but is hardly affected by noise can be realized.

著者

円谷 悠 毛利 宏

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.854, pp.17-00114-17-00114, 2017 (Released:2017-10-25)

参考文献数

8

被引用文献数

1

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This paper describes an investigation on the nonlinear filter that can realize its gain and phase characteristics independently. In the driver-vehicle closed loop system, it is reported that there is an optimal value in vehicle phase delay, i.e., excessive large or small delay deteriorates vehicle maneuverability. However, there is a strict relationship between the gain and phase delay in linear system. It is difficult to evaluate the gain and phase delay of vehicle response independently. In this investigation, we tried to design a non-linear filter that can set the relationship between gain and phase delay arbitrarily by using neural network. We investigate the effect of the gain and phase delay corresponding to the steering angle input on the ease of driving by using driving simulator, and evaluate the control performance on the lane change task. We verified that the ease of driving is improved by reducing a phase delay and decreasing a high frequency gain.

著者

川勝 俊輝 毛利 宏

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.854, pp.17-00099-17-00099, 2017 (Released:2017-10-25)

参考文献数

8

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Many articles have reported that the white lines painted on both sides of highways are used by automatically driven vehicles to control their lateral movement when driving. They are detected by stereo cameras or radars. And GPS is used as an additional information for improving its robustness and reliability. However, when we think about an urban area, the stereo cameras and radars cannot recognize any white lines because white lines do not exist at intersection. Therefore, a method for controlling a vehicle without environmental recognition becomes necessary. In our method, the steering angle is controlled by using simple map information comprising nodes and links of roads, which are widely used in navigation systems, and the data of the vehicle's position, which is obtained continuously. In addition, by using two front gaze points to solve the problem associated with one front gaze point, we propose a method that allows a vehicle to steer smoothly when turning at intersection. We performed an experiment using an actual vehicle under the same conditions as those used in the simulation. The results confirmed the validity of our proposed method because the target steering angles at each corner and the driving trajectory of the actual vehicle were almost the same as those obtained using the simulation.

著者

西崎 浩平 毛利 宏

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.852, pp.17-00137-17-00137, 2017 (Released:2017-08-25)

参考文献数

12

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Preceding vehicle following control system has been investigated widely. In many previous studies, the vehicular gap is assumed to be short, so the following vehicle can travel stably only by using heading angle toward preceding vehicle. However, the vehicle gap sometimes becomes longer at the complex surroundings such as intersection, so there is a problem that the following vehicle tends to travel along a shortcut path. Therefore, the preceding vehicle trajectory needs to be recognized correctly, but it is impossible because the system can use only current preceding vehicle position. We proposed the algorithm of the preceding vehicle trajectory generation. In the algorithm, the relative preceding vehicle position that is recognized at each period is hold. And each position is converted into the coordinate fixed to the present ego-vehicle. After that point sequence is generated by each position data. By using least squares method, the preceding vehicle point sequence is approximated by a curve line as the preceding vehicle trajectory. By using the trajectory as the target path for course following control, it becomes possible to follow the preceding vehicle regardless of the vehicular gap. Moreover, the validity of the proposed method is confirmed by the experiment conducted with an actual vehicle.

著者

風間 恵介 川勝 俊輝 赤木 康宏 毛利 宏

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.849, pp.17-00014-17-00014, 2017 (Released:2017-05-25)

参考文献数

17

被引用文献数

2

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This paper describes the development of a new localization method using a simple 2D map. The general method for localization using a 2D map is to match between the boundary line on the 2D map and the detected boundaries in the real world, i.e. lane markers, walls of building, or curbs. It is necessary to create a differential process in order to detect boundary lines of the road. If these methods try to detect small changes, the false-detection rate increases due to enhanced noises; if they try to reduce the effect of noise, boundary lines are misdetected. The estimation result of this method deteriorates drastically if the false-detection or misdetection of the boundary line occurs. We propose the new localization method based on the road area detection. First, the road map is extracted from the boundary lines on a 2D map. Next, the road plane image is made by the road area detected using LiDAR in the real world. Finally, the road map and the road plane image are matched by image registration. We confirmed that the proposed method have accurate estimation performance with several noise and low-cost calculation from the simulation. And we conducted the performance validation of proposed method in the real world. As a result, we confirmed the same tendency as simulation results.

著者

毛利 宏 永井 正夫

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. C編 (ISSN:03875024)

巻号頁・発行日

vol.67, no.664, pp.3836-3843, 2001-12-25

被引用文献数

3

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This paper compares two path-tracking control procedures, one using the steering angle as the control input and the other using steering torque as the input. This comparison will make clear the characteristics of both approaches. While steering angle control provides superior robustness, the control system configuration does not allow the driver to intervene in the steering process. In contrast, steering torque control provides some degree of freedom for allowing the driver to steer even during the control process, thus offering the potential for the provision of a steering assist mechanism.