Notification system

Abstract

To provide a notification system that gives a road surface sign to a traveling vehicle according to a proper timing dependent on a road situation.SOLUTION: A notification system includes plural road lamps which are connected to be able to communicate directly with one another and installed along a road. Each of the road lamps includes a video processing unit that detects presence or absence of a pedestrian who crosses a road and advances, and presence or absence of a vehicle which travels on the road, on the basis of image data obtained by imaging the road, a first signal processing unit that generates a pedestrian sense single in the event that a pedestrian is present, and transmits the pedestrian sense signal to the other road lamps, a second signal processing unit that generates a vehicle sense signal in the event that a vehicle is present, and transmits the vehicle sense signal to the other road lamps existing in the advancing direction of the vehicle, and a notification execution unit that, when both the pedestrian sense signal and vehicle sense signal sent from any other road lamps are received, makes notification for calling attention.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present disclosure relates to a notification system. [Background technology]

[0002] JP 2020-87884 A (Patent Document 1) describes a street light system that includes a plurality of street lights that are installed along roads on which vehicles travel and can be lit in a plurality of light colors including at least one warning color, each having a sound sensor that collects sound from the surrounding area and generates collected sound data; an acoustic signal processing unit that receives the collected sound data and detects a target sound that indicates an emergency vehicle and its source position based on the collected sound data, and generates emergency vehicle route data that indicates the current position and direction of travel of the emergency vehicle; and a light color control unit that generates a warning color lighting signal that instructs at least one street light installed on the path of the emergency vehicle to light up in a warning color based on the emergency vehicle route data. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-87884 Summary of the Invention [Problem to be solved by the invention]

[0004] One of the objectives of a specific aspect of the present disclosure is to provide a notification system that can notify traveling vehicles and the like of road markings and the like at appropriate timing according to road conditions. [Means for solving the problem]

[0005] An alarm system according to one aspect of the present disclosure includes: A notification system including a plurality of road lights installed along a road, which are directly connected to each other so as to be able to communicate with each other, Each of the plurality of roadway lights is an image processing unit that detects the presence or absence of a pedestrian crossing the road and the presence or absence of a vehicle traveling on the road based on image data obtained by photographing the road; a first signal processing unit that generates a pedestrian detection signal when the pedestrian is present and transmits the pedestrian detection signal to the other road lights; If the vehicle exists, sensing signal and transmits the vehicle detection signal to other road lights that are present in the traveling direction of the vehicle; and The pedestrian detection signal transmitted from the other road light and the vehicle sensing signal a notification execution unit that issues a notification to call attention when both of the above signals are received; Including, the first signal processing unit calculates an estimated crossing time required for the pedestrian to cross based on the moving speed of the pedestrian and the width of the road, and determines the road light to which the pedestrian detection signal is to be transmitted from among the other road lights according to the estimated crossing time. It is an alarm system.

[0006] According to the above configuration, a notification system is provided that can notify traveling vehicles of road markings and the like at appropriate timing according to road conditions. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram illustrating a schematic configuration of a notification system according to an embodiment. [Figure 2] Fig. 2(A) is a block diagram showing the overall configuration of the notification system, and Fig. 2(B) is a diagram showing a schematic diagram of the installation state of each road light. [Figure 3] FIG. 3 is a block diagram showing the configuration of each road light. [Figure 4] FIG. 4 is a diagram illustrating an example of the configuration of a computer system. [Figure 5] FIG. 5 is a diagram for explaining the photographing range of a street light camera and the information to be detected. [Figure 6]FIG. 6 is a flowchart showing the operation procedure of the road light. [Figure 7] FIG. 7 is a diagram schematically illustrating an example of a road situation. [Figure 8] FIG. 8 is a diagram for explaining the operation of each road light of the road drawing system in the road situation shown in FIG. [Figure 9] FIG. 9 is a diagram schematically showing another example of road conditions. [Figure 10] FIG. 10 is a diagram for explaining the operation of each road light of the road drawing system in the road situation shown in FIG. [Figure 11] FIG. 11 is a diagram illustrating an example of road data. DETAILED DESCRIPTION OF THE INVENTION

[0008] FIG. 1 is a diagram illustrating a schematic configuration of a notification system according to an embodiment. FIG. 1 schematically illustrates a road viewed from above. The notification system 100 according to this embodiment includes a plurality of road lights arranged at the side of a road. When a pedestrian (crossing person) 102 is crossing the road and a moving vehicle 103 or 104 is present on the road, road marking images 105 and 106 are drawn on the road surface visible to passengers (e.g., drivers) of the moving vehicles 103 and 104. Drawing these road marking images 105 and 106 alerts passengers of the moving vehicles 103 and 104 to the presence of the pedestrian 102, and also alerts the pedestrian 102 to the presence of the vehicles 103 and 104.

[0009] 2(A) is a block diagram showing the overall configuration of a notification system 100. The notification system 100 shown in the figure includes a plurality of street lights A1, A2, A3,...A9, and a management server 10 connected to each of these street lights A1 to A9 so as to be able to communicate with each other.

[0010] The street lights A1 to A9 are connected to each other so that they can communicate directly with each other without going through the management server 10. Specifically, the street lights A1 to A9 are associated with each other as one group, and are connected to each other so that they can communicate with each other within this group. Data transmitted from one street light can be transmitted to all other street lights and can be shared within the group. Each of the street lights A1 to A9 is assigned an individual identification number to identify it, and also assigned an installation location (latitude and longitude).

[0011] The road lights A1 to A9 are arranged at intervals along the road 12 on one side of the road 12, as shown in Fig. 2(B), for example. In the illustrated example, the mutual intervals D between the road lights A1 to A9 are constant, but this is not limiting. The road lights A1 to A9 are arranged above the road by supports, and are configured to irradiate light onto the road surface of the road 12 and to form road marking images 105, 106 (see Fig. 1).

[0012] The management server 10 is connected to each of the street lights A1 to A9 in a one-to-one communication manner. Communication between the management server 10 and each of the street lights A1 to A9 is configured to occur only when necessary in order to reduce the amount of communication data. Specifically, when a malfunction such as an inability to perform autonomous control is determined to have occurred in each of the street lights A1 to A9 by its own self-diagnosis function, the street light having the malfunction transmits data including malfunction information to the management server 10. In this case, the management server 10 takes over control of the street light having the malfunction.

[0013] Furthermore, the management server 10 communicates with each of the street lights A1 to A9 when a system update or the like becomes necessary. Furthermore, as necessary, the management server 10 can request each of the street lights A1 to A9 to transmit data indicating the operating status, image data generated by the cameras equipped in each of the street lights A1 to A9, and other data communicated between each of the street lights A1 to A9, and can also acquire this data.

[0014] 3 is a block diagram showing the configuration of each street light. Note that although the configuration of street light A1 is shown here, the other road lights A2 to A9 also have the same configuration as road light A1. The illustrated road light A1 is configured to include a camera 21, an autonomous control unit 22, a street light illumination unit 23, a notification control unit 24, a notification unit 25, and a communication unit 26.

[0015] The camera 21 is connected to the autonomous control unit 22, and captures an image of a road within a predetermined range corresponding to the location where the street light A1 is installed, and outputs the image data to the autonomous control unit 22.

[0016] The autonomous control unit 22 has an image processing unit 31 that detects the presence or absence of objects such as pedestrians and vehicles, as well as their respective traveling directions and speeds, by performing predetermined image processing on image data (video data) output from the camera 21, and a signal generation unit 32 that generates a signal indicating that the object has been detected in accordance with the object detection results by the image processing unit 31, and outputs the data to a signal transmission unit 33 of the communication unit 26. The autonomous control unit 22 can be realized, for example, by executing a predetermined operating program in a computer system such as that shown in Fig. 4, which will be described later.

[0017] The road light emitting unit 23 is connected to the autonomous control unit 22, and is turned on under the control of the autonomous control unit 22 at a predetermined time such as at night to emit light onto the road.

[0018] The notification control unit 24 is connected to the autonomous control unit 22, and controls the operation of the notification unit 25 based on signals generated by the signal generation unit 32 of the autonomous control unit 22, causing a predetermined road surface marking image to be drawn on the road. The notification control unit 24 is also connected to the signal receiving unit 34 of the communication unit 26, and controls the operation of the notification unit 25 based on signal data indicating the detection state of an object that is transmitted from the other road lights A2 to A9 and received by the signal receiving unit 34, causing a predetermined road surface marking image to be drawn on the road.

[0019] The notification unit 25 is connected to the notification control unit 24, and its operation is controlled by the notification control unit 24 to draw a predetermined road marking image on the road. The road marking image by the notification unit 25 can be set to various types such as letters, symbols, icons, etc. Furthermore, the notification by the notification unit 25 is not limited to a road marking image, but may be a side warning light, or may be a mode in which a notification is made directly to vehicles near the road light A1 via communication such as dedicated short-range communication. The following description will be mainly given taking a road marking image as an example.

[0020] The communication unit 26 is connected to the autonomous control unit 22, and is used for the street light A1 to perform data communication with the other street lights A2 to A9, and has a signal transmission unit 33 that transmits signal data generated by the signal generation unit 32 to each of the communication units 26 of the other street lights A2 to A9, and a signal reception unit 34 that receives signal data transmitted from each of the communication units 26 of the other street lights A2 to A9. The communication unit 26 is also connected to the notification control unit 24, and the signal data received by the signal reception unit 34 is also passed to the notification control unit 24.

[0021] In this embodiment, the signal generating unit 32 of the autonomous control unit 22 and the signal transmitting unit 33 of the communication unit 26 constitute a "first signal processing unit" and a "second signal processing unit", and the notification control unit 24, the notification unit 25, and the signal receiving unit 34 of the communication unit 26 constitute an "alert execution unit".

[0022] Fig. 4 is a diagram showing an example of the configuration of a computer system. The autonomous control unit 22, notification control unit 24, and communication unit 26 of each of the above-mentioned street lights A1, etc. can be configured using, for example, a computer system as shown in the figure. Specifically, the computer system shown in Fig. 4 is configured to include a CPU (Central Processing Unit) 201, a ROM (Read Only Memory) 202, a RAM (Temporary Storage Memory) 203, a storage device 204, a communication device 205, and an input / output unit 206. These CPUs 201, etc. are connected to each other via a bus so that they can communicate with each other.

[0023] The CPU 201 performs information processing by reading and executing a program 207 stored in the storage device 204. The ROM 202 stores basic control programs and the like required for the operation of the CPU 201. The RAM 203 temporarily stores data required for the information processing of the CPU 201. The storage device 204 is a large-capacity storage device for storing data, and is configured with a hard disk drive, a solid-state drive, or the like. The communication device 205 performs processing related to data communication with other external devices. The input / output unit 206 is an interface for connecting with external devices, and in this embodiment is used for connecting with the camera 21, the street light illumination unit 23, and the like.

[0024] FIG. 5 is a diagram illustrating the image capture range of a street light camera and the information detected. In FIG. 5, a predetermined range of the road corresponding to the installation position of the street light A1 is shown as a schematic view from above as an example, but the same applies to the other road lights A2 to A9. The angle of view and other factors of the image capture range of the camera 21 are set so as to include at least the range bounded by reference lines 140, 141 on both the left and right sides of the installation position of the street light A1 in the figure, and the near lane 130 and the far lane 131 based on the installation position of the street light A1. The same applies to the other road lights A2 to A9. It is preferable that the image capture range of each of the road lights A1 to A9 is set so that there are no gaps between the image capture ranges of adjacent road lights.

[0025] As shown in the figure, for example, it is assumed that there is a vehicle 103 traveling to the right in the figure in the lane behind the center line 132 based on the installation position of the road light A1, a vehicle 104 traveling to the left in the figure in front of the center line 132, and a pedestrian 102 attempting to cross from the front side to the back side of the center line 132. At this time, the image processing unit 31 of the autonomous control unit 22 detects the traveling direction and moving speed of each of the vehicles 103 and 104 by image processing.

[0026] Furthermore, the image processing unit 31 detects the moving direction and moving speed of the pedestrian 102 who is crossing the road by image processing. If the moving direction of the pedestrian 102 is the direction in which the pedestrian 102 is crossing the road, the image processing unit 31 detects the pedestrian 102 as a crosser. Note that regardless of the moving direction of the pedestrian 102, if the pedestrian 102 is present within the shooting range, the pedestrian 102 may be uniformly detected as a crosser.

[0027] Based on the detection results from the video processing unit 31, the signal generating unit 32 of the autonomous control unit 22 generates a vehicle detection signal indicating the presence of a vehicle 103 or vehicle 104, and generates a pedestrian detection signal indicating the presence of a pedestrian 102 crossing the street. The data of the vehicle detection signal and the pedestrian detection signal are each transmitted to a necessary road light among the other road lights A2 to A9. The method of determining the necessary road light will be described below.

[0028] As described above, the distance between adjacent road lights is D (see FIG. 2), the moving speed of the pedestrian 102 who is crossing is V1, the legal speed set for the road is V2, and the road width is L. In this case, the number of road lights that are targets for transmitting a pedestrian detection signal can be calculated, for example, using the following formula:

[0029] Number of street lights = {((L / V1) × (V2 + α)) / D} + 1

[0030] Here, α is a value for correcting the legal speed V2 according to the actual road conditions, and can be set to a value equivalent to the difference between the legal speed V2 and the average actual vehicle speed obtained by observing the target road over a certain period of time, for example.

[0031] In the above formula, the term (L / V1) is a term that calculates an estimate of the time (crossing time) required for a pedestrian 102 to cross the road. Multiplying this crossing time by the term (V2 + α) gives an estimate of the distance traveled by each vehicle during the crossing time. Dividing this estimated travel distance by the distance D between road lights gives an estimate of the number of road lights equivalent to the distance traveled by each vehicle. Furthermore, the addition of "+1" is to allow for a margin in the number of road lights, and this may be set to two or more depending on the situation. Based on the number of road lights calculated using this formula, pedestrian detection signal data is transmitted to neighboring road lights on both sides. For example, if the number of road lights calculated for road light A5 is two, pedestrian detection signal data is transmitted to road lights A3, A4, A6, and A7, the two road lights on either side of road light A5.

[0032] Below are some specific numerical examples and examples of calculating the number of street lights based on those examples. If the road width L is 7 (m), the moving speed V1 of the pedestrian 102 crossing is 1.3 (m / s), the legal speed V2 is 50 (km / h), i.e., 14 (m / s), the correction value α is 0 (m / s), and the distance D between the road lights is 30 (m), the number of road lights calculated based on the above calculation formula is 3.5, which can be rounded up to 4. In this case, using a certain road light as the base, pedestrian detection signal data is transmitted to four road lights on each side of it.

[0033] Furthermore, regardless of the presence or absence of a pedestrian 102, when vehicles 103 and 104 are present, the number of road lights that are targets for transmitting vehicle detection signals can be calculated as follows based on the expected stopping distance F predicted based on the vehicle speeds (traveling speeds) of these vehicles. Note that the expected stopping distance F refers to the distance that is expected to be required for a vehicle to stop, and may be determined based on the legal speed V2. Furthermore, the expected stopping distance F may be set variably depending on the weather, such as when it is raining.

[0034] Number of street lights = (F / D) + 1

[0035] As an example, if the expected stopping distance F on a dry road surface when the traveling speed is 50 km / h is 24.5 m and the distance D between road lights is 30 m, the number of road lights according to the above calculation formula is 1.81, which can be rounded up to 2. In this case, using a certain road light as the reference, vehicle detection signal data is transmitted to two road lights that exist in the direction of travel of the vehicle. For example, if only vehicle 103 is detected at road light A5 and its traveling direction is toward road light A6, vehicle detection signal data is transmitted to this road light A6 and the next road light A7.

[0036] 6 is a flowchart showing the operation procedure of a street light. Here, the operation of the street light A1 will be explained using the flowchart as an example, but it is assumed that the other street lights A2 to A9 are also performing similar operations in parallel. The order of each process can be changed as long as it does not cause inconsistencies in the control results, and other processes not explained can also be added, and these embodiments are not excluded.

[0037] The autonomous control unit 22 of the street light A1 performs a self-diagnosis to determine whether autonomous control is possible, and if autonomous control is not possible (step S11; NO), the autonomous control unit 22 transitions to a fail-safe control mode (step S12). The fail-safe control mode is a mode in which alternative control is performed by the management server 10.

[0038] If autonomous control is possible (step S11; YES), the image processing unit 31 of the autonomous control unit 22 performs image processing based on image data obtained from the camera 21, and if lanes are distinguishable (step S13; YES), the process proceeds to detection processing for pedestrians and moving vehicles. Here, "lanes are distinguishable" does not refer to a situation where lanes are hidden by snow or the like and cannot be detected by image processing, but rather a situation where lanes can be detected. The processing when lanes are not distinguishable (steps S25 and S26) will be described later.

[0039] If a pedestrian is present within the image capturing range (step S14; YES), the image processing unit 31 detects the crossing direction of the pedestrian and detects the crossing time of the pedestrian based on the road width L and the moving speed V1 of the pedestrian (step S15). sensing signal The number of street lights to which the signal is to be transmitted is calculated based on the above formula (step S16).

[0040] The signal generating unit 32 generates a pedestrian detection signal and detects the pedestrian with respect to other road lights determined based on the number of road lights calculated in step S16. sensing signal The data is transmitted (step S17).

[0041] On the other hand, if there is no pedestrian crossing the street (step S14; NO), the image processor 31 skips the processes of steps S15 to S17 and proceeds to the next process. Specifically, if there is a vehicle traveling within the shooting range (step S18; YES), the image processor 31 detects the vehicle's traveling direction and vehicle speed (step S19). The vehicle speed can be calculated, for example, based on the amount of change in the vehicle's position between one time and the next time and the elapsed time.

[0042] Next, the signal generating unit 32 calculates the number of road lights to which a vehicle detection signal is to be transmitted using the above formula based on the estimated stopping distance predicted from the calculated vehicle speed (step S20).

[0043] The signal generating unit 32 generates a vehicle detection signal and transmits data of this vehicle detection signal to other road lights determined based on the number of road lights calculated in step S20 (step S21). If no vehicle is present (step S18; NO), the process proceeds to step S22 without performing the processes of steps S19 to S21.

[0044] If the signal receiving unit 34 of the communication unit 26 has received the vehicle detection signal data transmitted from another road light (step S22; YES), and if the signal receiving unit 34 of the communication unit 26 has received the pedestrian detection signal data transmitted from another road light (step S23; YES), the notification control unit 24 controls the notification unit 25 to form a predetermined road marking image on the road surface. As a result, the road marking image is formed on the road surface (step S24). Thereafter, the process returns to step S11, and the subsequent processes are repeated.

[0045] If the vehicle detection signal data is not received from another road light (step S22; NO), or if the pedestrian detection signal data is not received from another road light (step S23; NO), the notification control unit 24 does not perform control to form a road marking image. In this case, too, the process returns to step S11, and the subsequent processes are repeated.

[0046] Furthermore, if the lanes cannot be identified in step S13 (step S13; NO), the image processor 31 reads out road data that has been prepared in advance and stored in a memory (not shown) (step S25), and synthesizes area information such as lanes with the image data acquired by the camera 21 based on this road data (step S26). The road data referred to here is assumed to be extracted from image data captured by the camera 21 of each road light A1, etc., when the road lights A1 to A9 are initially installed, for example, and stored in memory. By using such road data, it is possible to execute the processes from step S14 onwards even when lanes cannot be detected due to snow accumulation or the like. As shown in the figure, after the process of step S26 is performed, the process proceeds to step S14.

[0047] FIG. 7 is a diagram schematically illustrating an example of a road situation. FIG. 8 is a diagram for explaining the operation of each road light of the road drawing system in the road situation shown in FIG. 7. Here, it is assumed that, on a road 12 with one opposing lane as shown in FIG. 7, there are two vehicles 103 traveling in lane B on the far side of the drawing, one vehicle 104 traveling in lane C on the near side of the drawing, and a pedestrian 102 outside the road (on the side of the road). More specifically, one vehicle 103 in lane B is near road light A1 (opposite road light A2), and the other vehicle 103 is near road light A4, and they are both traveling to the right in the drawing. Furthermore, a vehicle 104 in lane C is near road light A9 and traveling to the left in the drawing. A pedestrian 102 is near road light A5 but is not crossing the road 12. That is, in this example, the pedestrian 102 is not a pedestrian.

[0048] As shown in Figure 8, pedestrian 102 is not a pedestrian, and therefore none of the road lights A1 to A9 detects a pedestrian. Therefore, for either lane B (line B) or lane C (line C), none of the road lights A1 to A9 generate or transmit a pedestrian detection signal, nor do they receive a pedestrian detection signal from the other road lights. On the other hand, road light A1 detects one vehicle 103 in lane B, and therefore transmits a vehicle detection signal to road light A2 located in the direction of travel of vehicle 103 according to the vehicle's speed. Since this vehicle 103 is located in front of road light A1 (on the left side in the figure), it also supplies a vehicle detection signal to its own notification control unit 24. The states in which a vehicle detection signal is received are indicated by circles in the figure.

[0049] Furthermore, road light A4 has detected another vehicle 103 in lane B, and therefore transmits a vehicle detection signal to road lights A5 to A7 that are located in the traveling direction of vehicle 103, depending on the vehicle speed. Furthermore, road light A9 has detected vehicle 104 in lane C, and therefore transmits a vehicle detection signal to road lights A6 to A8 that are located in the traveling direction of vehicle 104, depending on the vehicle speed. The states in which a vehicle detection signal is received are indicated by circles in the diagram.

[0050] For this reason, each of the road lights A1, A2, A4 to A8 receives a vehicle detection signal for lane B and / or lane C, but does not receive a pedestrian detection signal, so does not perform an operation to form a road marking image on the road surface. Also, the road light A3 does not receive either a vehicle detection signal or a pedestrian detection signal, so does not perform an operation to form a road marking image on the road surface. Therefore, in this example, none of the road lights A1 to A9 form a road marking image.

[0051] FIG. 9 is a diagram schematically illustrating another example of a road situation. FIG. 10 is a diagram for explaining the operation of each road light of the road drawing system in the road situation shown in FIG. 9. Here, assume that, on a road 12 with one opposing lane as shown in FIG. 9, there are two vehicles 103 traveling in lane B on the far side of the figure, one vehicle 104 traveling in lane C on the near side of the figure, and a pedestrian 102 crossing the road in lane B near road light A5. More specifically, one vehicle 103 in lane B is near road light A1, and the other vehicle 103 is near road light A6, and both are traveling to the right in the figure. Furthermore, a vehicle 104 in lane C is near road light A7 and traveling to the left in the figure. Furthermore, a pedestrian 102 crossing the road is near road light A5 and is about to cross the road 12.

[0052] As shown in Fig. 10, the pedestrian 102 is detected as a pedestrian by the road light A5. Therefore, the road light A5 generates a pedestrian detection signal and transmits a pedestrian detection signal for lane B (line B pedestrian detection signal) to the three road lights A2 to A4 on the left side of the road light A5 in the figure, and also transmits a pedestrian detection signal for lane C (line C pedestrian detection signal) to the three road lights A6 to A8 on the right side of the road light A5 in the figure. In addition, because the pedestrian 102 is heading toward lane C, the road light A5 also supplies to its own notification control unit 24 a pedestrian detection signal for lane B (line B pedestrian detection signal) and a pedestrian detection signal for lane C (line C pedestrian detection signal).

[0053] In addition, since the road light A1 detects one vehicle 103 in lane B, it transmits a vehicle detection signal for lane B (B-line vehicle detection signal) to the road lights A2 to A5 that are present in the traveling direction of the vehicle 103 according to the vehicle speed.

[0054] In addition, since the road light A6 detects another vehicle 103 in lane B, it transmits a vehicle detection signal for lane B (B-line vehicle detection signal) to the road lights A7 to A9 that are present in the direction of travel of the vehicle 103, depending on the vehicle speed.

[0055] In addition, since the road light A7 detects the vehicle 104 in lane C, it transmits a vehicle detection signal related to lane C (lane C vehicle detection signal) to the road lights A4 to A6 present in the traveling direction of the vehicle 104 according to the vehicle speed.

[0056] At this time, the road light A1 does not perform an operation to form a road marking image on the road surface because it has not received either the vehicle detection signal or the pedestrian detection signal for lane B and / or lane C. The road lights A2 to A5 receive the pedestrian detection signal (B-line pedestrian detection signal) and the vehicle detection signal (B-line vehicle detection signal) for lane B, and therefore form a road marking image 106 on the road surface of lane B as shown in FIG. 9. Furthermore, the road lights A5 and A6 receive the pedestrian detection signal (C-line pedestrian detection signal) and the vehicle detection signal (C-line vehicle detection signal) for lane C, and therefore form a road marking image 105 on the road surface of lane C as shown in FIG. 9. These road marking images 105 and 106 alert the occupants of the vehicles 103 and 104. In addition to the road marking images 105 and 106 as described above, a warning may be given by side warning lights or by dedicated short-range communication.

[0057] According to the above embodiment, each of the plurality of grouped road lights autonomously detects vehicles and pedestrians, and transmits and receives data of vehicle detection signals and pedestrian detection signals according to the detection results directly within the group without going through the server 10. Road marking images are formed for each lane at road lights that have acquired both vehicle detection signals and pedestrian detection signals. This reduces unnecessary attention calls, and makes it possible to call (notify) the attention of vehicle occupants and pedestrians in each vehicle by road markings or the like at appropriate times according to road conditions.

[0058] Furthermore, because only road marking images are formed by road lights whose number and positions correspond to the speed of pedestrians and vehicles, more road marking images than necessary are not formed, thereby reducing unnecessary warnings to vehicle occupants and pedestrians around the road.

[0059] Furthermore, since data is sent and received directly between each road light without going through a host device such as the server 10, communication delays can be reduced and vehicle detection signal and pedestrian detection signal data can be sent and received more quickly. This allows for control with finer time resolution, making it possible to build a notification system with excellent responsiveness.

[0060] The present disclosure is not limited to the content of the above-described embodiment, and various modifications can be made within the scope of the gist of the present disclosure. For example, in the above-described embodiment, a pedestrian is shown as an example of a crossing person, but a rider of a bicycle or the like may also be treated as a crossing person.

[0061] Furthermore, when each road light detects a pedestrian and a vehicle, the position at which the road marking image is formed by the road light may be shifted to the left or right in the direction of travel of the vehicle, rather than directly below the road light. This prevents the road marking image from overlapping with the pedestrian or other person crossing the road, making the road marking image easier to see.

[0062] Furthermore, the color tone or image type of the road sign image may be changed between day and night. For example, it is conceivable to form a road sign image in a color tone that is not easily obscured by sunlight during the day (for example, a strong reddish color tone because sunlight is close to white), and to form a road sign image in a color tone that is not easily obscured by other lighting at night (for example, any color tone different from other lighting, such as a white color tone or a stronger reddish color tone if the other lighting is yellowish).

[0063] Furthermore, the illumination state of each road light may be changed when forming a road sign image. For example, it is possible to make the brightness of the road sign image brighter than the brightness of the illumination light from the road light illumination unit 23 when forming the road sign image.

[0064] In addition, when a pedestrian or other person crossing the road diagonally, the system predicts the crossing distance from the direction of travel, calculates the time required for the crossing based on the predicted crossing distance, and sensing signal Alternatively, the number of street lights to which the signal is to be transmitted may be calculated.

[0065] Furthermore, the vehicle to be detected is not limited to the four-wheeled vehicle in the above embodiment, but various other vehicles such as two-wheeled vehicles may be detected.

[0066] In the above embodiment, the road width L is treated as a known value, but it may be acquired from image data obtained by a camera or a distance measurement sensor. In this case, values ​​such as the road width and travel speed may be treated as absolute values ​​(actual values), or may be treated as relative values ​​based on the number of pixels in the image data, the frame rate, etc.

[0067] As mentioned in the above embodiment, road data may be calculated in advance and stored in memory in case lanes cannot be detected due to snow accumulation or other reasons. Specifically, lane information, vehicle travel direction, number of lanes, road width (side strip width, lane width, center line / median strip width), etc. may be stored in memory as coordinate values ​​for two-dimensional information of image data captured by a road light camera. For example, as illustrated in FIG. 11, the image capture range for lane C can be defined by the coordinate values ​​(x1, y1), (x2, y2), (x3, y3), and (x4, y4). The vehicle travel direction can be defined as the direction from (x2, y2) and (x3, y3) to (x1, y1) and (x4, y4). Lane B can be defined in a similar manner. [Explanation of symbols]

[0068] A1 to A9: road lights, 10: management server, 12: road, 21: camera, 22: autonomous control unit, 23: road light illumination unit, 24: notification control unit, 25: notification unit, 26: communication unit, 31: image processing unit, 32: signal generation unit, 33: signal transmission unit, 34: signal reception unit, 100: notification system, 102: pedestrian (crossing person), 103, 104: vehicle, 105, 106: road marking image

Claims

1. A notification system including a plurality of road lights installed along a road, which are directly connected to each other so as to be able to communicate with each other, Each of the plurality of roadway lights is an image processing unit that detects the presence or absence of a pedestrian crossing the road and the presence or absence of a vehicle traveling on the road based on image data obtained by photographing the road; a first signal processing unit that generates a pedestrian detection signal when the pedestrian is present and transmits the pedestrian detection signal to the other road lights; a second signal processing unit that generates a vehicle detection signal when the vehicle is present and transmits the vehicle detection signal to other road lights that are present in the traveling direction of the vehicle; a notification execution unit that issues a notification to call attention when receiving both the pedestrian detection signal and the vehicle detection signal transmitted from another road light; Including, the first signal processing unit calculates an estimated crossing time required for the pedestrian to cross based on the moving speed of the pedestrian and the width of the road, and determines the road light to which the pedestrian detection signal is to be transmitted from among the other road lights according to the estimated crossing time. Notification system.

2. The notification by the notification execution unit is at least one selected from the group consisting of forming a road sign image on the road, a side warning light, and calling the attention of the vehicle through short-range communication. The notification system according to claim 1 .

3. the second signal processing unit determines the road light to which the vehicle detection signal is to be transmitted from among the other road lights in accordance with an estimated stopping distance corresponding to the moving speed of the vehicle. The notification system according to claim 1 or 2.

4. A notification system including a plurality of road lights installed along a road, which are directly connected to each other so as to be able to communicate with each other, Each of the plurality of roadway lights is an image processing unit that detects the presence or absence of a pedestrian crossing the road and the presence or absence of a vehicle traveling on the road based on image data obtained by photographing the road; a first signal processing unit that generates a pedestrian detection signal when the pedestrian is present and transmits the pedestrian detection signal to the other road lights; a second signal processing unit that generates a vehicle detection signal when the vehicle is present and transmits the vehicle detection signal to other road lights that are present in the traveling direction of the vehicle; a notification execution unit that issues a notification to call attention when receiving both the pedestrian detection signal and the vehicle detection signal transmitted from another road light; Including, the second signal processing unit determines the road light to which the vehicle detection signal is to be transmitted from among the other road lights in accordance with an estimated stopping distance corresponding to the moving speed of the vehicle. Notification system.

5. the second signal processing unit determines the road light to which the vehicle detection signal is to be transmitted from among the other road lights that are present in the traveling direction of the vehicle, The notification system according to claim 4.

6. a management server that is communicably connected to each of the plurality of street lights and manages each of the plurality of street lights; each of the plurality of road lights transmits and receives the pedestrian detection signal and the vehicle detection signal directly to and from each other without going through the management server; The notification system according to any one of claims 1 to 5.

7. Each of the plurality of street lights includes a camera that generates the image data. The notification system according to any one of claims 1 to 6.

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