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 an alert system.

Background Art

[0002] Japanese Unexamined Patent Application Publication No. 2020-87884 (Patent Document 1) describes a streetlight system including a plurality of streetlights installed along a road on which a vehicle travels, capable of lighting with a plurality of light colors including at least one warning color, each having a sound sensor that picks up sound from the surroundings and generates sound collection data, a sound signal processing unit that receives the sound collection data, detects a target sound indicating an emergency vehicle and its generation position based on the sound collection data, and generates emergency vehicle route data indicating the current position and traveling direction of the emergency vehicle, and a light color control unit that generates a warning color lighting signal for instructing lighting in a warning color for at least one streetlight installed on the route of the emergency vehicle based on the emergency vehicle route data.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] One of the objectives of the specific aspect according to the present disclosure is to provide an alert system capable of alerting a traveling vehicle or the like with road markings or the like at an appropriate timing according to road conditions.

Means for Solving the Problems

[0005] A notification system in one aspect of the present disclosure is a notification system comprising (a) a plurality of streetlights installed along a road and directly connected to each other in a manner that enables communication between them, (b) each of the plurality of streetlights comprising (b1) 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, (b2) a first signal processing unit that generates a pedestrian detection signal when a pedestrian is present and transmits the pedestrian detection signal to the other streetlights, (b3) a second signal processing unit that generates a vehicle detection signal when a vehicle is present and transmits the vehicle detection signal to the other streetlights in the direction of travel of the vehicle, and (b4) a notification execution unit that provides a warning when it receives both the pedestrian detection signal and the vehicle detection signal transmitted from the other streetlights.

[0006] According to the above configuration, a notification system is provided that can notify vehicles of road markings and other information at an appropriate time according to road conditions. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is a diagram illustrating the schematic configuration of a notification system according to one embodiment. [Figure 2] Figure 2(A) is a block diagram showing the overall configuration of the notification system. Figure 2(B) is a schematic diagram showing the installation status of each street light. [Figure 3] Figure 3 is a block diagram showing the configuration of each street light. [Figure 4] Figure 4 shows an example of a computer system configuration. [Figure 5] Figure 5 is a diagram illustrating the camera's field of view and the information it detects. [Figure 6] Figure 6 is a flowchart showing the operation procedure of a street light. [Figure 7] Figure 7 is a schematic diagram illustrating an example of road conditions. [Figure 8]Figure 8 is a diagram illustrating the operation of each street light in the road drawing system under the road conditions shown in Figure 7. [Figure 9] Figure 9 is a schematic diagram illustrating road conditions in another example. [Figure 10] Figure 10 is a diagram illustrating the operation of each street light in the road drawing system under the road conditions shown in Figure 9. [Figure 11] Figure 11 is a diagram illustrating an example of road data. [Modes for carrying out the invention]

[0008] Figure 1 is a diagram illustrating the schematic configuration of a notification system according to one embodiment. Figure 1 schematically shows an overhead view of a road. The notification system 100 of this embodiment is composed of multiple road lights placed along the side of the road, and when there is a pedestrian (crosser) 102 crossing the road and there are vehicles 103 and 104 on the road, it draws road marking images 105 and 106 on the road surface that are visible to the occupants (e.g., drivers) of each vehicle 103 and 104. By drawing such road marking images 105 and 106, the occupants of each vehicle 103 and 104 can be alerted to the presence of the pedestrian 102, and the pedestrian 102 can also be alerted to the presence of the vehicles 103 and 104.

[0009] Figure 2(A) is a block diagram showing the overall configuration of the notification system. The illustrated notification system 100 consists of multiple streetlights A1, A2, A3...A9 and a management server 10 that is connected to each of these streetlights A1 to A9 in a manner that enables communication.

[0010] Each of the streetlights A1 to A9 is connected to each other so that they can communicate directly without going through the management server 10. Specifically, each of the streetlights A1 to A9 is associated with each other as a single group, and they are connected to each other so that they can communicate with each other within this group. Data transmitted from one streetlight can be transmitted to all other streetlights and can be shared within the group. Each of the streetlights A1 to A9 is assigned a unique identification number for its own identification, as well as its installation location (latitude and longitude).

[0011] Each of the streetlights A1 to A9 is positioned along the road 12 on one outer side of the road 12, spaced apart from each other, as shown in Figure 2(B), for example. In the illustrated example, the distance D between each of the streetlights A1 to A9 is constant, but is not limited to this. Each of the streetlights A1 to A9 is positioned above the road by a support pole and is configured to emit light onto the road surface of the road 12 and to form road marking images 105, 106 (see Figure 1).

[0012] The management server 10 is connected to each of the streetlights A1 to A9 on a one-to-one basis for communication. Communication between the management server 10 and each of the streetlights A1 to A9 is configured to communicate only when necessary in order to reduce the amount of data transmitted. Specifically, when each of the streetlights A1 to A9 determines, through its own self-diagnostic function, that streetlight has a malfunction, such as being unable to perform autonomous control, it sends data containing malfunction information to the management server 10. In this case, the management server 10 takes over the control of the malfunctioning streetlight.

[0013] Furthermore, the management server 10 communicates with each street light A1 to A9 when necessary, such as for system updates. The management server 10 can also, as needed, request each street light A1 to A9 to transmit data indicating its operating status, image data generated by cameras installed in each street light A1 to A9, and other data communicated between each street light A1 to A9, and can acquire such data.

[0014] FIG. 3 is a block diagram showing the configuration of each street light. Here, the configuration of street light A1 is shown, but street lights A2 to A9 also have the same configuration as street light A1. The illustrated street light A1 includes 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, captures an image of a predetermined range of the road 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 includes a video processing unit 31 that performs predetermined image processing on the image data (video data) output from the camera 21 to detect the presence or absence of objects such as pedestrians and vehicles, their respective traveling directions, and speeds, and a signal generation unit 32 that generates a signal indicating that these objects have been detected according to the detection result of the objects by the video processing unit 31 and outputs the data to the signal transmission unit 33 of the communication unit 26. This autonomous control unit 22 can be realized by executing a predetermined operation program in a computer system as shown in FIG. 4 described later, for example.

[0017] The street light irradiation unit 23 is connected to the autonomous control unit 22 and lights up during a predetermined time period such as at night under the control of the autonomous control unit 22 to irradiate light onto the road.

[0018] The notification control unit 24 is connected to the autonomous control unit 22, controls the operation of the notification unit 25 based on the signal generated by the signal generation unit 32 of the autonomous control unit 22, and causes a predetermined road surface marking image to be drawn on the road. In addition, the notification control unit 24 is connected to the signal reception unit 34 of the communication unit 26, controls the operation of the notification unit 25 based on the data of the signal indicating the detection state of the object transmitted from other street lights A2 to A9 and received by the signal reception unit 34, and causes 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 in various ways, such as characters, symbols, or icons. Furthermore, the notification by the notification unit 25 is not limited to a road marking image; it may also be a side warning light, or it may be a method of directly notifying nearby vehicles of the road light A1 through communication such as dedicated narrow-area communication. In the following explanation, we will mainly use road marking images as an example.

[0020] The communication unit 26 is connected to the autonomous control unit 22 and is used for data communication between streetlight A1 and other streetlights A2 to A9. It includes a signal transmission unit 33 that transmits signal data generated by the signal generation unit 32 to each communication unit 26 of the other streetlights A2 to A9, and a signal receiving unit 34 that receives signal data transmitted from each communication unit 26 of the other streetlights A2 to A9. The communication unit 26 is also connected to the notification control unit 24, and the signal data received by the signal receiving unit 34 is also passed to the notification control unit 24.

[0021] In this embodiment, the signal generation unit 32 of the autonomous control unit 22 and the signal transmission unit 33 of the communication unit 26 constitute the "first signal processing unit" and the "second signal processing unit," while the notification control unit 24, notification unit 25, and the signal receiving unit 34 of the communication unit 26 constitute the "notification execution unit."

[0022] Figure 4 shows 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 streetlights A1 can be configured using a computer system like the one shown. Specifically, the computer system shown in Figure 4 includes a CPU (Central Processing Unit) 201, ROM (Read-Only Memory) 202, RAM (Temporary Memory) 203, storage device 204, communication device 205, and input / output unit 206. These components, such as the CPU 201, are connected to each other via a bus so that they can communicate with one another.

[0023] The CPU 201 performs information processing by reading and executing the program 207 stored in the memory device 204. The ROM 202 stores basic control programs and other information necessary for the operation of the CPU 201. The RAM 203 temporarily stores data necessary for information processing by the CPU 201. The memory device 204 is a large-capacity storage device for storing data and is composed of a hard disk drive or a solid-state drive. 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, etc.

[0024] Figure 5 is a diagram illustrating the shooting range and detected information of a streetlamp camera. In Figure 5, as an example, a schematic view from above of a predetermined area of ​​road corresponding to the installation position of streetlamp A1 is shown, but the same applies to the other streetlamps A2 to A9. The shooting range of camera 21 is set to include at least the area enclosed by the reference lines 140 and 141 on both the left and right sides of the installation position of streetlamp A1 in the figure, and the lane 130 on the near side and the lane 131 on the far side, based on the installation position of streetlamp A1. The same applies to the other streetlamps A2 to A9. Furthermore, it is preferable that the shooting range for each of the streetlamps A1 to A9 is set so that there are no gaps between the shooting ranges of adjacent streetlamps.

[0025] As shown in the figure, for example, with respect to the installation position of streetlamp A1, a vehicle 103 traveling to the right in the figure is located in the lane beyond the center line 132, a vehicle 104 traveling to the left in the figure is located in front of the center line 132, and a pedestrian 102 is attempting to cross from the front of the center line 132 towards the back. In this case, the video processing unit 31 of the autonomous control unit 22 detects the direction of travel and speed of movement for each of the vehicles 103 and 104 by image processing.

[0026] Furthermore, the video processing unit 31 detects the direction of travel and speed of the pedestrian 102, who is crossing the road, through image processing. The video processing unit 31 then detects the pedestrian 102 as a crosser if the direction of travel of the pedestrian 102 is in the direction of crossing the road. Alternatively, regardless of the direction of travel of the pedestrian 102, if a pedestrian 102 is present in the shooting range, the pedestrian 102 may be uniformly detected as a crosser.

[0027] The signal generation unit 32 of the autonomous control unit 22 generates a vehicle detection signal indicating the presence of vehicles 103 and 104 based on the detection results from the video processing unit 31, and generates a pedestrian detection signal indicating the presence of a pedestrian 102 crossing the road. These vehicle detection signals and pedestrian detection signals are transmitted to the necessary road lights among the other road lights A2 to A9. The method for determining the necessary road lights is described below.

[0028] As described above, let D be the distance between adjacent streetlights (see Figure 2), let V1 be the speed of pedestrian 102 crossing the road, V2 be the legal speed limit set for the road, and L be the road width. In this case, the number of streetlights to which a pedestrian detection signal is to be transmitted can be calculated, for example, using the following formula.

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

[0030] Here, α is a value used to correct the legal speed limit V2 according to actual road conditions, and can be set to a value equivalent to the difference between the actual average speed of vehicles observed on the target road over a certain period of time and the legal speed limit V2.

[0031] In the above calculation formula, the (L / V1) term is used to estimate the time required for pedestrian 102 to cross the road (crossing time). By multiplying this crossing time by the (V2+α) term, an estimated distance traveled by each vehicle within the crossing time can be obtained. By dividing this estimated distance by the distance D between streetlights, an estimated number of streetlights can be obtained for the distance traveled by each vehicle. The "+1" is added to allow for a margin in the number of streetlights, and this can be set to 2 or more depending on the situation. Based on the number of streetlights obtained by this calculation formula, data for pedestrian detection signals is transmitted to the streetlights on both sides of the vicinity. For example, if the number of streetlights obtained for streetlight A5 is 2, data for pedestrian detection signals will be transmitted to streetlights A3, A4, A6, and A7, which are two on either side of streetlight A5.

[0032] The following shows specific numerical examples and calculations of the number of streetlights based on them. Assuming the road width L is 7 (m), the pedestrian crossing speed V1 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 streetlights is 30 (m), the number of streetlights calculated using the above formula is 3.5, which can be rounded up to 4. In this case, data for pedestrian detection signals is transmitted to 4 streetlights on each side of a given streetlight.

[0033] Furthermore, regardless of the presence or absence of pedestrians 102, if vehicles 103 and 104 are present, the number of streetlights to which vehicle detection signals are to be transmitted can be determined as follows, based on the estimated stopping distance F predicted by the speed (travel speed) of these vehicles. The estimated stopping distance F is the distance that is expected to be required for a vehicle to come to a stop, and may be determined based on the legal speed limit V2. The estimated stopping distance F may also be set to be variable depending on the weather, such as in rainy weather.

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

[0035] For example, if the assumed stopping distance F on a dry road surface at a driving speed of 50 km / h is 24.5 m, and the distance D between streetlights is 30 m, then the number of streetlights calculated using the above formula is 1.81, which can be rounded up to 2. In this case, vehicle detection signal data is transmitted to two streetlights located in the direction of the vehicle's travel, using a given streetlight as a reference. For example, if only vehicle 103 is detected at streetlight A5, and its direction of travel is towards streetlight A6, then vehicle detection signal data is transmitted to streetlight A6 and the next streetlight A7.

[0036] Figure 6 is a flowchart illustrating the operation procedure of a streetlamp. Here, streetlamp A1 is used as an example to explain its operation according to the flowchart, but it is assumed that other streetlamps A2 to A9 perform similar operations in parallel. Furthermore, the order of each process can be changed as long as it does not cause inconsistencies in the control results, and other processes not described may be added, and these variations are not excluded.

[0037] The autonomous control unit 22 of the street light A1 performs a self-diagnosis to determine if autonomous control is possible. If autonomous control is not possible (step S11; NO), it switches to fail-safe control mode (step S12). 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 video processing unit 31 of the autonomous control unit 22 performs image processing based on the image data obtained from the camera 21, and if the lane can be identified (step S13; YES), it proceeds to the detection process of pedestrians and moving vehicles. "Lane can be identified" here means a situation in which the lane can be detected, not a situation in which the lane is hidden by the effects of snow, for example and detection by image processing cannot be performed. The processing when the lane cannot be identified (steps S25, S26) will be described later.

[0039] If a pedestrian is present in the shooting range (step S14; YES), the video processing unit 31 detects the direction of the pedestrian's crossing and, based on the road width L and the pedestrian's movement speed V1, detects the time the pedestrian crosses (step S15). The signal generation unit 32 calculates the number of streetlights to which the pedestrian detection signal will be transmitted based on the above calculation formula (step S16).

[0040] The signal generation unit 32 generates a pedestrian detection signal and transmits this pedestrian detection signal data to other road lights determined based on the number of road lights calculated in step S16 (step S17).

[0041] On the other hand, if there are no pedestrians crossing the road (step S14; NO), the video processing unit 31 does not perform the processes in steps S15 to S17 and proceeds to the next process. Specifically, if there is a moving vehicle in the shooting range (step S18; YES), the video processing unit 31 detects the direction of travel of the vehicle and also detects the vehicle speed (step S19). The vehicle speed can be determined, for example, based on the amount of change in the vehicle's position between a certain time and the next time and the elapsed time.

[0042] Next, the signal generation unit 32 calculates the number of streetlights to which a vehicle detection signal will be transmitted using the above calculation formula, based on the estimated stopping distance predicted by the determined vehicle speed (step S20).

[0043] The signal generation unit 32 generates a vehicle detection signal and transmits this vehicle detection signal data 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 processes in steps S19 to S21 are not performed and the process proceeds to step S22.

[0044] If the notification control unit 24 has received vehicle detection signal data transmitted from other streetlights by the signal receiving unit 34 of the communication unit 26 (step S22; YES), and if the data of pedestrian detection signal data transmitted from other streetlights has also been received by the signal receiving unit 34 of the communication unit 26 (step S23; YES), it controls the notification unit 25 to form a predetermined road marking image on the road surface. As a result, a road marking image is formed on the road surface (step S24). The process then returns to step S11, and the subsequent processing is repeated.

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

[0046] Furthermore, if the lane cannot be identified in step S13 (step S13; NO), the video processing unit 31 reads road data that has been prepared in advance and stored in memory (not shown) (step S25), and based on this road data, synthesizes area information such as lanes with the image data obtained by the camera 21 (step S26). The road data referred to here is, for example, extracted from image data of the shooting range of each road light A1 to A9, etc., captured by the camera 21, etc., during the initial installation of each road light A1 to A9, and stored in memory. By using such road data, the processes from step S14 onwards described above can be executed even when the lane cannot be detected due to snow cover, etc. As shown in the figure, after the processing in step S26 is performed, the process proceeds to step S14.

[0047] Figure 7 is a schematic diagram illustrating an example of road conditions. Figure 8 is a diagram illustrating the operation of each road light in the road rendering system in the road conditions shown in Figure 7. Here, we assume that on a road 12 with one lane in each direction, as shown in Figure 7, there are two vehicles 103 traveling in lane B on the far side of the diagram, one vehicle 104 traveling in lane C on the near side of the diagram, and a pedestrian 102 is outside the road (on the shoulder). In detail, one vehicle 103 in lane B is near road light A1 (opposite side of road light A2), and the other vehicle 103 is near road light A4, both traveling to the right in the diagram. Vehicle 104 in lane C is near road light A9 and is traveling to the left in the diagram. Pedestrian 102 is near road light A5 but is not crossing road 12. In other words, in this example, pedestrian 102 is not a crosser.

[0048] As shown in Figure 8, since pedestrian 102 is not a crosser, none of the streetlights A1 to A9 detect a crosser. Therefore, for both lane B (lane B) and lane C (lane C), none of the streetlights A1 to A9 generate or transmit a crosser detection signal, nor do they receive any crosser detection signals from other streetlights. On the other hand, streetlight A1 detects one vehicle 103 in lane B, and therefore transmits a vehicle detection signal to streetlight A2 located in the direction of travel of vehicle 103, according to the vehicle's speed. Since vehicle 103 is located in front of streetlight A1 (to the left in the figure), it also supplies a vehicle detection signal to its own notification control unit 24. The state of having a vehicle detection signal is indicated by a circle in the figure.

[0049] Furthermore, since streetlight A4 has detected another vehicle 103 in lane B, it transmits a vehicle detection signal to streetlights A5-A7 located in the direction of vehicle 103's travel, according to the vehicle's speed. Also, since streetlight A9 has detected vehicle 104 in lane C, it transmits a vehicle detection signal to streetlights A6-A8 located in the direction of vehicle 104's travel, according to the vehicle's speed. The state in which a vehicle detection signal is present is indicated by a circle in the figure.

[0050] Therefore, streetlights A1, A2, and A4-A8 each receive vehicle detection signals related to lane B and / or lane C, but do not receive pedestrian detection signals, and thus do not perform the operation to form a road marking image on the road surface. Also, streetlight A3 does not receive either vehicle detection signals or pedestrian detection signals, and therefore does not perform the operation to form a road marking image on the road surface. Consequently, in this example, none of streetlights A1-A9 form a road marking image.

[0051] Figure 9 is a schematic diagram illustrating road conditions in another example. Figure 10 is a diagram illustrating the operation of each streetlamp in the road rendering system in the road conditions shown in Figure 9. Here, we assume that on a single-lane road 12 with opposing traffic, as shown in Figure 9, there are two vehicles 103 traveling in lane B (farthest from the viewer) and one vehicle 104 traveling in lane C (nearest from the viewer), and a pedestrian 102 crossing the road is located in lane B near streetlamp A5. In detail, one vehicle 103 in lane B is located near streetlamp A1, and the other vehicle 103 is located near streetlamp A6, both traveling to the right in the diagram. Vehicle 104 in lane C is located near streetlamp A7 and is traveling to the left in the diagram. Pedestrian 102 is located near streetlamp A5 and is about to cross the road 12.

[0052] As shown in Figure 10, pedestrian 102 is detected as a crosser by streetlight A5. Therefore, streetlight A5 generates a crosser detection signal and transmits a crosser detection signal related to lane B (lane B crosser detection signal) to the three streetlights A2-A4 on the left side of streetlight A5 in the figure, and a crosser detection signal related to lane C (lane C crosser detection signal) to the three streetlights A6-A8 on the right side of streetlight A5 in the figure. In addition, since pedestrian 102 is heading towards lane C, streetlight A5 also supplies a crosser detection signal related to lane B (lane B crosser detection signal) and a crosser detection signal related to lane C (lane C crosser detection signal) to its own notification control unit 24.

[0053] Furthermore, since streetlight A1 has detected one vehicle 103 in lane B, it transmits a vehicle detection signal (lane B vehicle detection signal) related to lane B to streetlights A2 to A5 located in the direction of travel of vehicle 103, according to the vehicle's speed.

[0054] Furthermore, since streetlight A6 has detected another vehicle 103 in lane B, it transmits a vehicle detection signal (lane B vehicle detection signal) related to lane B to streetlights A7 to A9 located in the direction of travel of vehicle 103, depending on the vehicle's speed.

[0055] Furthermore, since streetlight A7 has detected vehicle 104 in lane C, it transmits a vehicle detection signal (C-lane vehicle detection signal) related to lane C to streetlights A4 to A6 located in the direction of vehicle 104's travel, according to the vehicle's speed.

[0056] At this time, since streetlight A1 has not received either a vehicle detection signal or a pedestrian detection signal for lane B and / or lane C, it does not perform the operation of forming a road marking image on the road surface. Streetlights A2 to A5 have received a pedestrian detection signal (lane B pedestrian detection signal) and a vehicle detection signal (lane B vehicle detection signal) for lane B, so they form a road marking image 106 on the road surface of lane B as shown in Figure 9. In addition, since streetlights A5 and A6 have received a pedestrian detection signal (lane C pedestrian detection signal) and a vehicle detection signal (lane C vehicle detection signal) for lane C, they form a road marking image 105 on the road surface of lane C as shown in Figure 9. These road marking images 105 and 106 alert the occupants of each vehicle 103 and 104. In addition to the road marking images 105 and 106 as described above, notification may also be provided by side warning lights or by dedicated narrow-area communication.

[0057] According to the above embodiment, each of the grouped streetlights autonomously detects vehicles and pedestrians, and transmits and receives vehicle detection signals and pedestrian detection signals directly within the group without going through the server 10, based on the detection results. A road marking image is formed for each lane at the streetlights that have acquired both vehicle detection signals and pedestrian detection signals. As a result, unnecessary warnings are suppressed, and warnings (notifications) such as road markings can be provided to the occupants of each vehicle and pedestrians at an appropriate timing according to the road conditions.

[0058] Furthermore, since only the number and position of road lights corresponding to the speed of pedestrians and vehicles are used to form road marking images, an excessive number of road marking images are not created. Consequently, unnecessary warnings to vehicle occupants and pedestrians around the road are suppressed.

[0059] Furthermore, since data is transmitted and received directly between each street light without going through a host device such as server 10, communication delay is reduced, and vehicle detection signals and pedestrian detection signals can be transmitted and received more quickly. Consequently, control becomes possible with finer temporal resolution, making it possible to construct a notification system with excellent responsiveness.

[0060] It should be noted that this disclosure is not limited to the embodiments described above, and can be implemented in various ways within the scope of the gist of this disclosure. For example, in the embodiments described above, pedestrians were shown as an example of a person crossing the road, but a person riding a bicycle or the like may also be treated as a person crossing the road.

[0061] Furthermore, if a streetlamp detects both a pedestrian and a vehicle, it may be configured to create the road marking image not directly below the streetlamp, but shifted to either the left or right in the direction of the vehicle's movement. This avoids overlapping the road marking image with the pedestrian or other crossing person, making the road marking image more visible.

[0062] Furthermore, the color tone and image type of road markings may be changed between day and night. For example, during the day, road markings could be created with a color tone that is less likely to be obscured by sunlight (for example, a strong red tone since sunlight is close to white), and at night, road markings could be created with a color tone that is less likely to be obscured by other lighting (for example, any color tone that is different from other lighting; if other lighting is yellowish, a white tone or a stronger red tone may be used).

[0063] Furthermore, the lighting conditions may be changed when forming the road marking image at each streetlamp. For example, when forming the road marking image, the brightness of the road marking image may be made brighter than the brightness of the illumination light from the streetlamp lighting unit 23.

[0064] Furthermore, if a pedestrian or other person crossing the road is crossing diagonally, the crossing distance may be predicted from their direction of travel, the time required for their movement may be calculated based on the predicted crossing distance, and the number of streetlights to which a pedestrian detection signal should be transmitted may be calculated.

[0065] Furthermore, the vehicles to be detected are not limited to the four-wheeled vehicles in the embodiments described above, but may include various other vehicles such as two-wheeled vehicles.

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

[0067] Furthermore, as mentioned in the embodiments described above, road data may be obtained in advance and stored in memory in case lane detection is not possible due to snow or other reasons. Specifically, lane information, vehicle direction of travel, number of lanes, road width (shoulder width, lane width, center line / median width), etc., can be stored in memory as coordinate values ​​for the 2D information of image data from the street light camera. For example, as illustrated in Figure 11, the shooting range of lane C can be defined by the coordinate values ​​(x1,y1), (x2,y2), (x3,y3), and (x4,y4). The vehicle direction of travel can be defined as the direction from (x2,y2) and (x3,y3) to (x1,y1) and (x4,y4). The same definition can be applied to lane B. [Explanation of Symbols]

[0068] A1-A9: Streetlights, 10: Management server, 12: Road, 21: Camera, 22: Autonomous control unit, 23: Streetlight illumination unit, 24: Notification control unit, 25: Notification unit, 26: Communication unit, 31: Video processing unit, 32: Signal generation unit, 33: Signal transmission unit, 34: Signal reception unit, 100: Notification system, 102: Pedestrian (crosser), 103,104: Vehicle, 105,106: Road marking images

Claims

1. A notification system including a plurality of road lights installed along a road, the road lights being directly connected to each other so as to be able to communicate with each other, Each of the plurality of street 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 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 a traveling direction of the vehicle; a notification execution unit that issues a notification to call attention when the pedestrian detection signal and the vehicle detection signal transmitted from another road light are both received; Including, the first signal processing unit calculates an estimated crossing time required for the pedestrian to cross the road 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 marking image on the road, a side warning light, and calling the attention of the vehicle by 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 according to an expected 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, the road lights being directly connected to each other so as to be able to communicate with each other, Each of the plurality of street 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 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 a traveling direction of the vehicle; a notification execution unit that issues a notification to call attention when the pedestrian detection signal and the vehicle detection signal transmitted from another road light are both received; Including, the second signal processing unit determines, according to an assumed stopping distance corresponding to a moving speed of the vehicle, the road light to which the vehicle detection signal is to be transmitted from among the other road lights; Notification System

5. the second signal processing unit determines a road light to which the vehicle detection signal is to be transmitted from among the other road lights present in a 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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