Signal control system and signal control method

Abstract

A signal control system is provided with: a means for assessing passage possibility that is capable of acquiring an image of a road from a camera disposed near the road in an area being controlled and, on the basis of an abnormality in the image captured by the camera, assesses whether a road section that starts at an intersection is passable; and, a signal control means for controlling a traffic light at an intersection that includes the road section, so as to deter traffic from entering an impassable section.

Description

[Technical Field]

[0001] The present invention relates to a signal control system, a signal control method, and a program recording medium. [Background technology]

[0002] Patent Document 1 discloses a traffic signal control device that can perform traffic response control to increase vehicle safety in the event of a disaster and suppress traffic disruptions in the event of a disaster. The traffic signal control device described in this document stores evacuation routes within a control area in the event of a disaster, and performs guidance control to set signal control parameters for intersections included in the evacuation routes so that vehicles can easily travel along the evacuation routes when a disaster actually occurs within the control area. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-305090 Summary of the Invention [Problem to be solved by the invention]

[0004] The following analysis has been provided by the inventor. The method of Patent Document 1 requires that evacuation routes be set in advance. This poses a problem in that it is not possible to provide guidance that takes into account blocked sections of the evacuation route. Furthermore, if a road is blocked due to road surface damage or a vehicle accident, the additional influx of vehicles into that section may cause congestion and delay evacuation.

[0005] The present invention aims to provide a signal control system, a signal control method, and a program recording medium that can prevent further inflow of vehicles into a section that is closed due to road surface damage, a vehicle accident, etc. [Means for solving the problem]

[0006] According to the first viewpoint, cameras placed around the roads in the area to be controlled It is possible to obtain road images from A signal control system is provided that includes a passability determination means that determines whether a road section starting from an intersection is passable based on abnormalities in the image captured by the camera, and a signal control means that controls traffic signals at the intersection that includes the road section to prevent traffic from flowing into the closed section.

[0007] According to a second aspect, there is provided a traffic signal control method in which a computer capable of acquiring images from cameras arranged around roads in a control target area determines whether a road section starting from an intersection is passable or not based on abnormalities in the images taken by the cameras, and controls a traffic signal at an intersection including the road section to prevent traffic from flowing into the closed section. This method is linked to a specific machine, namely a computer capable of acquiring images from cameras arranged around roads in a control target area.

[0008] According to a third aspect, there is provided a computer program (hereinafter, "program") for realizing the functions of the signal control system described above. This computer program is input to a computer device via an input device or a communication interface from the outside, stored in a storage device, and drives a processor according to predetermined steps or processes. This program can display the processing results, including intermediate states as needed, at each stage on a display device, or can communicate with the outside via the communication interface. For example, a computer device for this purpose typically includes a processor, a storage device, an input device, a communication interface, and, as needed, a display device, all of which are connectable to one another via a bus. This program can be recorded on a computer-readable (non-transitive) storage medium. That is, the present invention can also be embodied as a computer program product. [Effects of the Invention]

[0009] The present invention can contribute to preventing further influx of vehicles into sections that are closed due to road surface damage, vehicle accidents, etc. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a diagram showing a configuration of an embodiment of the present invention; [Figure 2] FIG. 2 is a diagram for explaining the operation of one embodiment of the present invention. [Figure 3] FIG. 2 is a diagram for explaining the operation of one embodiment of the present invention. [Figure 4] 1 is a diagram illustrating a configuration of a signal control system according to a first embodiment of the present invention. [Figure 5] FIG. 2 is a diagram showing an example of the arrangement of fixed cameras used in the first embodiment of the present invention. [Figure 6] FIG. 3 is a diagram illustrating an example of camera information stored in a camera information storage unit according to the first embodiment of the present invention. [Figure 7] 3 is a diagram showing an example of traffic light information stored in a traffic light information storage unit according to the first embodiment of the present invention; FIG. [Figure 8] 3 is a flowchart showing the operation of the signal control system according to the first embodiment of the present invention. [Figure 9] FIG. 2 is a diagram for explaining the operation of the signal control system according to the first embodiment of the present invention. [Figure 10] FIG. 2 is a diagram for explaining the operation of the signal control system according to the first embodiment of the present invention. [Figure 11] FIG. 10 is a diagram for explaining the configuration and operation of a traffic light used in a second embodiment of the present invention. [Figure 12] FIG. 10 is a diagram illustrating a configuration of a signal control system according to a third embodiment of the present invention. [Figure 13] FIG. 10 is a diagram for explaining the operation of the signal control system according to the fourth embodiment of the present invention. [Figure 14] FIG. 1 is a diagram showing the configuration of a computer that can function as the signal control system of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] First, an overview of one embodiment of the present invention will be described with reference to the drawings. Note that the reference numerals in this overview are used for convenience to identify each element as an example to facilitate understanding, and are not intended to limit the present invention to the illustrated embodiment. Furthermore, connecting lines between blocks in the drawings and the like referred to in the following description include both bidirectional and unidirectional lines. Unidirectional arrows are used to schematically indicate the flow of main signals (data) and do not exclude bidirectionality. Furthermore, ports or interfaces are present at the input / output connection points of each block in the drawings, but are not shown. A program is executed via a computer device, which includes, for example, a processor, a storage device, an input device, a communication interface, and, if necessary, a display device. Furthermore, this computer device is configured to be able to communicate with internal or external devices (including computers) via the communication interface, whether wired or wireless.

[0012] In one embodiment, the present invention can be realized by a traffic light control system 10 configured to acquire road images from cameras 20 arranged around roads in a control target area, as shown in Fig. 1. This traffic light control system 10 includes a passability determination means 11 and a signal control means 12 capable of controlling a traffic signal (hereinafter referred to as a traffic light) 30.

[0013] More specifically, the passability determination means 11 determines whether a road section starting from an intersection is passable or not based on abnormalities in the image captured by the camera 20. Then, the traffic light control means 12 controls the traffic lights at the intersection including the road section to prevent traffic from flowing into the closed section.

[0014] For example, it is assumed that evacuation routes are set in the area to be controlled as shown in Fig. 2. Then, when the signal control system 10 detects an abnormality in the image captured by the camera 20, it operates as follows.

[0015] First, the signal control system 10 determines whether or not a road section starting from an intersection is passable based on an abnormality in an image captured by the camera 20. Here, it is assumed that an abnormality indicated by the symbol X in Fig. 3 has been detected and the road section is determined to be impassable.

[0016] At this time, the signal control means 12 controls the traffic signals at the intersection including the road section in order to prevent traffic from flowing into the closed section where the abnormality indicated by the symbol X has been detected. In the example of Fig. 3, the signal control is performed using the blue light arrow to prevent vehicles moving from the north side (upper side of Fig. 3) along the evacuation route from entering the closed section (specifically, no left turns).

[0017] This prevents vehicles traveling from the north (upper side of Figure 3) along the evacuation route from entering the closed section, worsening congestion at the scene, and causing further secondary damage to the vehicle. While the above example describes the use of blue arrow lights to prohibit entry into the closed section, the signal light pattern is not limited to this, as long as it can prevent entry into the closed section. For example, at the relevant intersection, red lights may be lit or flashing, and a message may be displayed to drivers via audio or a sign to notify them that they are prohibited from entering the closed section.

[0018] [First embodiment] Next, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 4 is a diagram showing the configuration of the first embodiment of the present invention. Referring to FIG. 4, the configuration of a signal control system 100 connected to a camera 200, a camera information storage unit 103, and a traffic light information storage unit 104 is shown. The signal control system 100 includes a passability determination unit 101 and a signal control unit 102. Such a signal control system 100 can be realized by a traffic control server or an MEC (Multi-access Edge Computing) server installed near the service area. In addition to these devices, the signal control system 100 can also adopt a distributed configuration in which some functions are distributed to computers installed in the traffic lights.

[0019] Fig. 5 is a diagram showing an example of the placement of camera 200 used in the first embodiment of the present invention. In the following embodiment, a description will be given assuming that camera 200 is attached to a traffic light 500 at an intersection, as shown in Fig. 5. One advantage of using such a camera attached to traffic light 500 is that, as shown in Fig. 5, it can be installed in a position that provides a view of the intersection and the road beyond, and that existing signal control systems can be used for power supply and communication means. Of course, camera 200 is not limited to camera 200 attached to traffic light 500 shown in Fig. 5, and any other camera installed around the road can be used.

[0020] The passability determining unit 101 detects abnormalities in the image captured by the camera 200. The following methods can be considered as methods for detecting abnormalities in the image. (1) Comparison with a reference image of the road taken in advance The passability determination unit 101 compares a reference image of the road taken in advance with the image taken by the camera 200. This makes it possible to detect damage to the road, the presence or absence of fallen objects, the presence or absence of flooding, etc. (2) Abnormalities in the flow of vehicles on the road The passability determination unit 101 compares the pre-set vehicle flow line on the road with the vehicle flow line in the image captured by the camera 200. This method can also detect the presence or absence of damage to the road or fallen objects. (3) Whether or not there is any movement of the vehicle in the image in opposition to the signal lights. The passability determination unit 101 checks the state of the traffic lights in the image and the movement of the vehicle in the image, and if the vehicle's movement is contrary to the state of the traffic lights, it presumes that there is an abnormality on the road. For example, if the traffic lights in the image are green but the vehicle is not moving for a long time, the passability determination unit 101 determines that there is an abnormality. At this time, the passability determination unit 101 may also check whether or not there is a person in the vehicle. For example, if a vehicle is stopped in the center of a lane and there is no person in the vehicle, it can be assumed that the person in the vehicle has left the vehicle for some reason. In this case, the passability determination unit 101 also determines that there is an abnormality.

[0021] When an abnormality is detected in an image as described above, the passability determination unit 101 determines whether the road section shown in the image is passable or not based on the content of the abnormality. For example, the passability determination unit 101 determines whether the road section is passable or not based on the size of holes or fallen objects on the road and the degree of flooding. In addition, if the flow of vehicles on the road significantly deviates from the normal flow of vehicles or if vehicles are not moving, the passability determination unit 101 can also determine whether the road section is passable or not based on the extent of the deviation.

[0022] If it is determined that the road is impassable, the passability determining unit 101 refers to the camera information storage unit 103, identifies the impassable section (non-passable section), and requests the signal control unit 102 to perform control.

[0023] Fig. 6 is a diagram showing an example of camera information stored in the camera information storage unit 103. In the example of Fig. 6, a road section (photographed section) photographed by each camera 200 is set. For example, if the camera 200 with camera ID = 0001 determines that a road is impassable, the road section between intersections A001 and A002 is identified as the impassable section.

[0024] When the signal control unit 102 receives information about the closed section from the passability determination unit 101, it references the traffic light information storage unit 104 to acquire information about the traffic lights 500 at the intersections on both ends of the closed section. It then causes the traffic lights 500 on both ends of the closed section to start displaying a light pattern that prohibits entry into the closed section.

[0025] Fig. 7 is a diagram showing an example of traffic light information stored in the traffic light information storage unit 104. In the example of Fig. 7, the IDs of the traffic lights located at each intersection and their type information are set. For example, it is shown that intersection A001 has four traffic lights with traffic light IDs 1001N to 1001W, all of which have three arrow lights indicating left, straight, and right.

[0026] The signal control unit 102 refers to the traffic light information as described above, determines a light pattern that prohibits entry into the closed section according to the type information, and starts displaying the light pattern.

[0027] Next, the operation of this embodiment will be described in detail with reference to the drawings. Fig. 8 is a flow chart showing the operation of the signal control system 100 according to the first embodiment of the present invention after detecting an abnormality in an image. Referring to Fig. 8, first, the signal control system 100 refers to the camera information storage unit 103 to identify the road section in which the abnormality in the image was detected (step S001). Here, for example, it is assumed that the section between intersections A001 and A002 in Fig. 9 has become blocked.

[0028] Next, the traffic light control system 100 refers to the traffic light information storage unit 104 to identify traffic lights at intersections that are endpoints of the identified road section (step S002). For example, it is assumed here that traffic lights 1001N, 1001W, and 1001S at intersection A001 in Figures 9 and 10 have been identified.

[0029] Next, the signal control system 100 determines the control content to be instructed to the identified traffic light (step S003). In order to prevent entry into the aforementioned closed section, the signal control system 100 determines, for example, for traffic light 1001N in Fig. 9, the aspect of a green light arrow that allows only straight ahead and right turns, instead of a green light. Similarly, for example, for traffic light 1001S in Fig. 9, the signal control system 100 determines, for example, for traffic light 1001W in Fig. 10, the aspect of a green light arrow that allows only right turns and left turns, instead of a green light.

[0030] Finally, the signal control system 100 notifies the identified traffic light of the determined control content (step S004). As a result, vehicles are prevented from entering the closed section, as shown in Figures 9 and 10. Although omitted in Figures 9 and 10, the traffic light at intersection A002 may also be instructed to turn on its lights to prevent vehicles from entering the closed section.

[0031] As described above, according to this embodiment, the camera 200 can detect sections that are closed due to road surface damage, vehicle accidents, etc., and can prevent further inflow of vehicles into the closed section.

[0032] [Second embodiment] Next, a second embodiment will be described in which, instead of the blue arrow light, a flashing red light and a message are displayed to prohibit vehicles from entering the closed section. The configuration and operation of the second embodiment are almost the same as those of the first embodiment, so the following description will focus on the differences.

[0033] Fig. 11 is a diagram for explaining the configuration and operation of a traffic light used in the second embodiment of the present invention. As shown in Fig. 11, the traffic light used in the second embodiment is equipped with an electric display board 31, which is capable of displaying a message along with a flashing red light.

[0034] When the signal control unit 102 of this embodiment receives information about a closed section from the passability determination unit 101, it causes the traffic lights at both ends of the closed section to flash red lights and display a message prohibiting entry into the closed section. In the example of Fig. 11, the message displayed is "No right turn due to road flooding." This makes it possible to issue an instruction equivalent to the green arrow light on the traffic light 1001S in Fig. 9.

[0035] According to this embodiment, in addition to the effects of the first embodiment, Not only the display of lights, It will be possible to communicate the status of the closed section and the reason for prohibiting entry. Of course, instead of displaying the message "Road flooded, no right turns," it would also be possible to make announcements such as "Road flooded between intersections A001 and A002" or "No entry east from intersection A001" from speakers installed in traffic lights, etc.

[0036] In the above-described embodiment, the electric indicator board 31 need only be installed in a location visible to the driver of the vehicle, and does not necessarily have to be attached to a traffic light.

[0037] [Third embodiment] Next, we will explain a third embodiment, which not only controls traffic signals but also notifies vehicles in the surrounding area of ​​the existence and location of blocked sections. The configuration and operation of the second embodiment are almost the same as those of the first embodiment, so the following explanation will focus on the differences.

[0038] Fig. 12 is a block diagram showing the configuration of a signal control system 100a according to the third embodiment of the present invention. The difference from the signal control system 100 according to the first embodiment shown in Fig. 4 is that an interrupted section occurrence notification unit 105 is added.

[0039] When the blocked section occurrence notification unit 105 receives notification that a blocked section exists from the passability determination unit 101, it functions as a notification means for transmitting the location of the blocked section to the on-board terminal of the vehicle 400 in the control target area. Note that the method of notifying the vehicle 400 of the blocked section from the signal control system 100a can be to notify the on-board terminal as road traffic information using any communication means provided by a communication carrier, such as a wireless communication line, a broadcast line, or road-to-vehicle communication.

[0040] The on-board terminal of the vehicle 400 that receives the notification of the unserviceable section can display that fact on a display device or the location on a map. Furthermore, if a route guidance service is in progress, the on-board terminal of the vehicle 400 can also provide guidance on a detour route that avoids the unserviceable section.

[0041] Furthermore, if the vehicle 400 in the control target area is an autonomous vehicle, or if the driving route is known in advance, the signal control system 100a may calculate a detour route. In this case, the signal control system 100a may provide the calculated detour route in addition to the blocked section.

[0042] As described above, according to this embodiment, it is possible to reliably notify vehicles 400 in the control target area of ​​the occurrence of an unserviceable section.

[0043] [Fourth embodiment] The first and second embodiments described above can also be combined. Specifically, a fourth embodiment will be described in which the signal control system 100 selectively displays (A) a blue light arrow or (B) a red light flashing and a message based on the content of an abnormality in an image captured by the camera 200. The configuration and operation of the fourth embodiment are almost the same as those of the first embodiment, so the following description will focus on the differences.

[0044] FIG. 13 is a diagram illustrating a specific example of signal control by the signal control system according to the fourth embodiment of the present invention. In FIG. 13, the symbol X indicates a closed section containing an abnormality. In the example of FIG. 13, the signal control system 100 selectively displays (A) a green arrow light or (B) a flashing red arrow light and outputs a message based on the distance between the traffic light and a location determined to be abnormal in the image captured by the camera. Specifically, the signal control system 100 instructs the traffic light at intersection A002, which is close to the closed section, to display (A) a green arrow light to prevent vehicles from entering the closed section (first control). Meanwhile, the signal control system instructs the traffic light at intersection A001, which is far from the closed section, to flash (B) a red arrow light and output a message (second control). As a result, the signal control system reduces the number of vehicles heading from intersection A001 to intersection A002 and explicitly specifies the direction of travel at the immediately preceding intersection A002.

[0045] Note that the example in Figure 13 is merely one example, and various modifications can be made based on the content of the abnormality in the image. For example, (B) red lights may be flashed and a message may be output at intersection A002 close to the closed section, and (A) blue lights and an arrow may be output at intersection A001 away from the closed section. In this case, it may be preferable to change the content of the message at intersection A002 close to the closed section. For example, a message informing of the danger of entering the closed section, such as "Flooded area ahead, submerged vehicles ahead," may be displayed.

[0046] As described above, according to this embodiment, it is possible to control traffic volume in stages according to the content of the abnormality in the image, and it is possible to reduce the occurrence of congestion around intersections where traffic is restricted.

[0047] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and further modifications, substitutions, and adjustments can be made without departing from the basic technical concept of the present invention. For example, the device configurations, element configurations, and data representations shown in the drawings are examples intended to aid in understanding the present invention, and the present invention is not limited to the configurations shown in these drawings.

[0048] For example, in the above embodiment, the camera 200 is described as a camera installed at an intersection, but the example of the camera 200 is not limited to this. Also, in the above embodiment, the signal control system is described as detecting the occurrence of an interrupted section based on an image from the camera, but the signal control system may also detect the occurrence of an interrupted section by referring to other information. For example, the signal control system may also detect the occurrence of an interrupted section by using disaster information from local governments and the Japan Meteorological Agency, and information from probe cars.

[0049] In addition, in the above embodiment, the camera information storage unit 103 and the traffic light information storage unit 104 are described as being provided outside the signal control system, but these storage units may also be provided in an auxiliary storage device of a computer that constitutes the signal control system.

[0050] In addition, in the above-described embodiments, the signal control system has been described as using a blue arrow light, a flashing red light, and message output, but the light pattern is not limited to this as long as it can prevent traffic from flowing into the closed section. For example, if permitted by traffic laws and regulations, a configuration can be adopted in which a flashing red light is turned on simultaneously with a blue arrow light, or a flashing blue light is used to attract the driver's attention.

[0051] The procedures shown in the above-described embodiments can be realized by a program that causes a computer (9000 in FIG. 14) that functions as a signal control system to realize the functions of the signal control system. Such a computer is exemplified by a configuration including a CPU (Central Processing Unit) 9010, a communication interface 9020, a memory 9030, and an auxiliary storage device 9040 in FIG. 14. That is, the CPU 9010 in FIG. 14 may be made to execute a passability determination program and a signal control program.

[0052] In other words, each part (processing means, function) of the above-mentioned signal control systems 100, 100a can be realized by a computer program that causes a processor installed in these devices to execute each of the above-mentioned processes using its hardware.

[0053] Finally, preferred embodiments of the present invention will be summarized. [First form] (See the first aspect of the signal control system above.) [Second form] The signal control means of the above-mentioned signal control system is The control contents of the traffic signal include: A configuration can be adopted in which blue light arrows are used to prevent traffic from entering the closed section. [Third Form] The signal control means of the above-mentioned signal control system is The control contents of the traffic light further include: A configuration can be adopted in which control is implemented to change the lighting devices in all directions to flashing red lights and to output a message prohibiting the closed section. [Fourth Form] The signal control means of the above-mentioned signal control system is Based on the content of the abnormality in the image captured by the camera, a first control to prevent traffic from entering the closed section by means of a blue light arrow; or A second control that changes the lighting devices in all directions to flashing red lights and outputs a message prohibiting the non-serviceable section; It is possible to adopt a configuration that implements any one of the above. [Fifth Form] The signal control means of the above-mentioned signal control system is Based on the distance between the traffic light and the location determined to be abnormal in the image captured by the camera, A configuration can be adopted in which either the first control or the second control is performed. [Sixth Form] The judgment means of the above-mentioned signal control system can be configured to detect abnormalities in the road by comparing it with a reference image of the road taken in advance, and to judge whether the road section is passable or not. [7th form] The judgment means of the above-mentioned signal control system can be configured to detect abnormalities in the road by comparing the pre-set vehicle movement lines on the road with the vehicle movement lines in the image, and to judge whether the road section is passable or not. [8th form] The determination means of the above-mentioned signal control system can be configured to detect road abnormalities based on the presence or absence of vehicle movement in the image contrary to the signal lights, and determine whether the road section is passable or not. [9th Form] The above-mentioned signal control system further comprises: The control system may be configured to include a notification means for notifying vehicles located in the control target area of ​​the occurrence of the non-operational section. [10th Form] (See the second aspect of signal control method above.) [11th Form] (See the program recording medium according to the third aspect above.) The tenth and eleventh embodiments can be expanded into the second to ninth embodiments in the same manner as the first embodiment.

[0054] The disclosures of the above-cited patent documents are incorporated herein by reference and may be used as the basis or part of the present invention, as necessary. Modifications and adjustments of the embodiments and examples are possible within the scope of the entire disclosure of the present invention (including the claims), and further based on its basic technical concept. Furthermore, various combinations and selections (including partial deletions) of the various disclosed elements (including each element of each claim, each element of each embodiment or example, each element of each drawing, etc.) are possible within the scope of the disclosure of the present invention. In other words, the present invention naturally embraces various modifications and alterations that would be possible by a person skilled in the art in accordance with the entire disclosure and technical concept, including the claims. In particular, with regard to the numerical ranges set forth herein, any numerical value or subrange within that range should be construed as specifically set forth, even if not otherwise specified. Furthermore, the disclosures of the above-cited documents, when used in part or in whole in combination with the disclosures herein as part of the disclosure of the present invention, in accordance with the spirit of the present invention, are also deemed to be included in the disclosures of this application. [Explanation of symbols]

[0055] 10, 100, 100a signal control system 11 Passability determination means 12 Signal control means 20,200 cameras 30, 500, 1001N, 1001S, 1001W, 1002W traffic lights 31 Electric display board 101 Passability determination section 102 Signal control section 103 Camera information storage unit 104 Traffic light information storage unit 105 Unserviceable section occurrence notification section 400 vehicles A001~A003 intersection X Section not in service 9000 computers 9010 CPU 9020 Communication Interface 9030 Memory

Claims

1. It is possible to acquire images of roads from cameras placed around roads in the area to be controlled, a passability determination means for determining whether a road section starting from an intersection is passable based on an abnormality in the image captured by the camera; a signal control means for controlling a traffic signal at an intersection including the road section so as to prevent traffic from flowing into the closed section; a notification means for notifying vehicles located in the control target area of ​​the occurrence of the non-serviceable section; a camera information storage means for storing, for each camera, the road section photographed by that camera; The passability determination means determines that the road section stored in the camera information storage means in association with the camera that captured the image in which the abnormality was detected is the impassable section. Signal control system.

2. The signal control means The control contents of the traffic signal include: The blue arrow lights will be used to prevent traffic from entering the closed section. The signal control system of claim 1.

3. The signal control means The control contents of the traffic signal further include: The lights in all directions are changed to flashing red lights, and a message prohibiting entry into the closed section is output.

3. The signal control system according to claim 1 or 2.

4. The signal control means Based on the content of the abnormality in the image captured by the camera, a first control that prevents traffic from entering the closed section by means of a blue light arrow; or A second control that changes the lighting devices in all directions to flashing red lights and outputs a message prohibiting entry into the closed section; Implement one of the following:

4. The signal control system according to claim 1.

5. The signal control means Based on the distance between the traffic signal and the location determined to be abnormal in the image captured by the camera, Implementing either the first control or the second control. The signal control system of claim 4.

6. 6. A signal control system according to claim 1, wherein the passability determination means detects abnormalities in the road by comparing the image with a reference image of the road taken in advance, and determines whether the road section is passable.

7. the passability determination means detects abnormalities in the road by comparing a predetermined path of vehicles on the road with the path of vehicles in the image, and determines whether the road section is passable; 7. A signal control system according to any one of claims 1 to 6.

8. 8. The traffic signal control system according to claim 1, wherein the passability determination means detects abnormalities in the road based on the presence or absence of vehicle movement in the image contrary to signal lights, and determines whether the road section is passable.

9. A traffic light control method executed by a computer capable of acquiring images from cameras arranged around roads in a control target area, comprising: the computer includes a camera information storage means for storing, for each camera, the road section photographed by that camera; The signal control method includes: a passability determination step of determining whether a road section starting from an intersection is passable or not based on an abnormality in the image captured by the camera; a signal control step of controlling a traffic signal at an intersection including the road section so as to prevent traffic from flowing into the closed section; a notification step of notifying vehicles located in the control target area of ​​the occurrence of the non-serviceable section, In the passability determination step, the road section stored in the camera information storage means in association with the camera that captured the image in which the abnormality was detected is determined to be the closed section.

Images