Roadside device and notification method

Abstract

To improve a technology for notifying pedestrians and vehicles of warning information.SOLUTION: A roadside device 20 comprises a control unit 24 which stores a reference image photographed in a state in which the roadside device 20 is installed at a reference posture, calculates a deviation amount between a photographic range of an image photographed after the reference image is stored and a photographic range of the reference image, and notifies a server 30 of information prompting restoration of a posture of the roadside device 20 when the deviation amount is a threshold or greater.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a roadside device and a notification method.

Background Art

[0002] Conventionally, technologies for notifying pedestrians and vehicles of information have been known. For example, Patent Document 1 discloses a notification system that notifies vehicles and pedestrians other than the automated driving vehicle of passage permission or caution information, etc., according to the behavior of an automated driving vehicle scheduled to pass through a predetermined traffic area.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The roadside device can be installed at any location, and when a pedestrian is detected from the video of a camera mounted on the roadside device, a notification is made. Here, for example, if the orientation of the roadside device changes unintentionally for some reason after installation, such as a pedestrian hitting the roadside device, the angle of view or the shooting range of the camera changes, and the detection accuracy of pedestrians may decrease. Therefore, there is room for improvement in the technology for notifying pedestrians and vehicles of information.

[0005] In view of such circumstances, an object of the present disclosure is to improve the technology for notifying pedestrians and vehicles of information.

Means for Solving the Problems

[0006] The roadside device according to an embodiment of the present disclosure is a roadside device including a notification unit, a photographing unit, a storage unit, and a control unit. The control unit stores a reference image photographed by the photographing unit in the storage unit in a state where the roadside device is installed in a reference posture. After the reference image is stored, the control unit calculates a deviation amount between a photographing range of an image photographed by the photographing unit and a photographing range of the reference image. When the deviation amount is equal to or greater than a threshold value, the control unit notifies the server via the notification unit of information prompting restoration of the posture of the roadside device.

[0007] A notification method according to an embodiment of the present disclosure is a notification method executed by a roadside device. The method includes storing a reference image photographed in a state where the roadside device is installed in a reference posture, calculating a deviation amount between a photographing range of a photographed image and a photographing range of the reference image after the reference image is stored, and notifying the server of information prompting restoration of the posture of the roadside device when the deviation amount is equal to or greater than a threshold value.

Advantages of the Invention

[0008] According to an embodiment of the present disclosure, the technology for notifying pedestrians and vehicles of information is improved.

Brief Description of the Drawings

[0009]

Figure 1

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Embodiments for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present disclosure will be described.

[0011] (Overview of Embodiment) Referring to FIG. 1, an overview of the system 1 according to an embodiment of the present disclosure will be described. The system 1 includes a vehicle 10, a roadside device 20, and a server 30. The vehicle 10, the roadside device 20, and the server 30 are communicably connected to a network 2 including, for example, the Internet and a mobile communication network.

[0012] The vehicle 10 is, for example, an automobile, but is not limited thereto and may be any vehicle. The automobile may be a gasoline vehicle, a BEV (Battery Electric Vehicle), an HEV (Hybrid Electric Vehicle), a PHEV (Plug-in Hybrid Electric Vehicle), an FCEV (Fuel Cell Electric Vehicle), or the like, but is not limited thereto. In the present disclosure, the vehicle 10 is an autonomous driving vehicle 10 having an autonomous driving function. However, the vehicle 10 is not limited to the autonomous driving vehicle 10. The number of autonomous driving vehicles 10 included in the system 1 may be arbitrarily determined. The autonomous driving vehicle 10 is communicably connected to the roadside device 20 via the network 2.

[0013] The roadside device 20 is an information communication device that, when detecting a pedestrian heading for the road from a camera image, notifies the pedestrian and notifies the autonomous driving vehicle 10 approaching the pedestrian. In addition, the roadside device 20 notifies the server 30 of information for promoting the restoration of the posture of the roadside device 20. The roadside device 20 is communicably connected to the autonomous driving vehicle 10 and the server 30 via the network 2.

[0014] The server 30 is a computer owned by the administrator (management center) of the roadside device 20. The server 30 communicates with the roadside device 20 via the network 2.

[0015] First, the outline of this embodiment will be described, and the details will be described later. The roadside device 20 stores a reference image captured by the imaging unit 22 in the storage unit 23 in a state where the roadside device 20 is installed in a reference posture. After the reference image is stored, the deviation amount between the imaging range of the image captured by the imaging unit 22 and the imaging range of the reference image is calculated. When the deviation amount is equal to or greater than a threshold value, information prompting the restoration of the posture of the roadside device 20 is notified to the server 30 via the notification unit 21.

[0016] In this way, when the deviation amount between the imaging range of the captured image and the imaging range of the reference image is equal to or greater than the threshold value, the roadside device 20 notifies the server 30 of information prompting the restoration of the posture of the roadside device 20. The administrator of the server 30 that has received the notification can recognize the change in the posture that has occurred in the roadside device 20 at an early stage, and thus can quickly take measures such as returning the posture of the roadside device 20 to the reference posture. Therefore, the technology for notifying information to pedestrians and vehicles is improved in terms of improving the detection accuracy of pedestrians heading towards the roadway.

[0017] Next, each component of the system 1 will be described in detail.

[0018] (Configuration of the vehicle) As shown in FIG. 1, the vehicle 10 (autonomous vehicle 10) includes a communication unit 11, an output unit 12, and a control unit 13.

[0019] The communication unit 11 includes one or more communication interfaces connected to the network 2. The communication interface corresponds to, for example, a mobile communication standard such as 4G (4th Generation) or 5G (5th Generation), or an in-vehicle network (for example, CAN (Controller Area Network)), but is not limited thereto. In this embodiment, the autonomous vehicle 10 communicates with the roadside device 20 via the communication unit 11 and the network 2.

[0020] The output unit 12 includes at least one voice output interface capable of outputting voice, and at least one display interface capable of displaying characters or video. The voice output interface is, for example, a speaker that outputs information received from the roadside device 20 by voice. The display interface is, for example, a display such as an LCD or an organic EL display that outputs map information or information received from the roadside device 20 by characters or video. However, the voice output interface and the display interface are not limited to these.

[0021] The control unit 13 includes one or more processors, one or more programmable circuits, one or more dedicated circuits, or a combination thereof. The processor is, for example, a general-purpose processor such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit), or a dedicated processor specialized for specific processing, but is not limited thereto. The programmable circuit is, for example, an FPGA (Field-Programmable Gate Array), but is not limited thereto. The dedicated circuit is, for example, an ASIC (Application Specific Integrated Circuit), but is not limited thereto. The control unit 13 controls the operation of the entire autonomous vehicle 10.

[0022] (Configuration of roadside device) As shown in FIG. 1, the roadside device 20 includes a notification unit 21, a photographing unit 22, a storage unit 23, a control unit 24, and a support column 20A.

[0023] The notification unit 21 includes one or more communication interfaces connected to the network 2. The communication interface corresponds to, for example, a mobile communication standard, a wired LAN (Local Area Network) standard, or a wireless LAN standard, but is not limited thereto, and may correspond to any communication standard. In the present embodiment, the roadside device 20 communicates with the autonomous vehicle 10 and the server 30 via the notification unit 21 and the network 2.

[0024] Furthermore, the notification unit 21 includes at least one of (i) a speaker that notifies a pedestrian of the approach of the autonomous vehicle 10 by voice, (ii) a display that notifies by characters or video, and (iii) a signal lamp that notifies by flashing of light, but the information notification method is not limited to these.

[0025] The imaging unit 22 includes a video camera 22A and captures a moving image or a still image of a pedestrian heading toward the roadway.

[0026] The storage unit 23 includes one or more memories. Each memory included in the storage unit 23 may function as, for example, a main storage device, an auxiliary storage device, or a cache memory. The storage unit 23 stores any information used for the operation of the roadside device 20. For example, the storage unit 23 may store a system program, an application program, a database, and images captured by the imaging unit 22. The information stored in the storage unit 23 may be updated with information acquired from the network 2 via the communication unit 211, for example.

[0027] The control unit 24 includes one or more processors, one or more programmable circuits, one or more dedicated circuits, or a combination thereof. The control unit 24 controls the operation of the entire roadside device 20.

[0028] The support column 20A is a column used to support the roadside device 20 (the notification unit 21, the imaging unit 22, the storage unit 23, and the control unit 24). The support column 20A is installed on the roadside strip of the roadway or the like, but the installation location is not limited to this.

[0029] (Configuration of the server) As shown in FIG. 1, the server 30 includes a communication unit 31, a storage unit 32, and a control unit 33.

[0030] The communication unit 31 includes one or more communication interfaces for connecting to the network 2. The communication interface may correspond to, for example, a mobile communication standard, a wired LAN (Local Area Network) standard, or a wireless LAN standard, but is not limited thereto and may correspond to any communication standard. In the present embodiment, the server 30 communicates with the roadside device 20 via the communication unit 31 and the network 2.

[0031] The storage unit 32 includes one or more memories. Each memory included in the storage unit 32 may function as, for example, a main storage device, an auxiliary storage device, or a cache memory. The storage unit 32 stores any information used for the operation of the server 30. For example, the storage unit 32 may store a system program, an application program, a database, and information about the roadside device 20 to be managed. The information stored in the storage unit 32 may be updated with information acquired from the network 2 via the communication unit 31, for example.

[0032] The control unit 33 includes one or more processors, one or more programmable circuits, one or more dedicated circuits, or a combination thereof. The control unit 33 controls the operation of the entire server 30.

[0033] (Operation flow of roadside device) With reference to FIG. 2, the operation of the roadside device 20 according to the present embodiment will be described. This operation relates to the notification of information for promoting the restoration of the posture of the roadside device 20.

[0034] FIG. 3 is a schematic diagram showing an installation example of the roadside device. As shown in FIG. 3, the autonomous vehicle 10 travels on the road lane 3, and the pedestrian 4 crosses the road lane 3 at a crosswalk 5 or the like. The roadside device 20 can be installed at any location. In the example shown in FIG. 3, the roadside device 20 is attached to a support column 20A installed in the roadside strip 6 of the road lane 3 near the crosswalk 5, for example. The imaging unit 22 of the roadside device 20 includes a video camera 22A. The position and orientation of the video camera 22A are adjusted so as to be able to detect the pedestrian 4 heading towards the road lane.

[0035] S101 - S102: The control unit 24 stores the reference image captured by the imaging unit 22 (video camera 22A) in the storage unit 23 in a state where the roadside device 20 is installed in the reference posture.

[0036] The imaging unit 22 (video camera 22A) captures a moving image or a still image of the pedestrian 4 heading towards the roadway 3. In the example of FIG. 3, the video camera 22A is attached to, for example, a support column 20A installed on the roadside strip 6 of the roadway 3, but the attachment location may be any location on the support column 20A.

[0037] FIG. 4 is a schematic diagram showing an example of the posture of the roadside device 20. As shown in FIG. 4, in the present disclosure, the reference posture is the posture of the support column 20A that supports the roadside device 20, and it is the posture in which the support column 20A faces the vertical direction lp. However, the support column 20A may be set up with a predetermined tolerance α in the circumferential direction from the vertical direction lp. The video camera 22A attached to the support column 20A set up in such a basic posture is adjusted to a position and orientation capable of securing an imaging range R1 for detecting the pedestrian 4 heading towards the roadway 3. As shown in FIG. 4, when the posture of the support column 20A changes from the basic posture due to a collision of a vehicle (motorcycle), etc., the imaging range of the video camera 22A shifts (changes) accordingly.

[0038] S103: The imaging unit 22 starts imaging the image.

[0039] The control unit 24 starts imaging the image after the reference image is stored. The control unit 24 may store the captured image in the storage unit 23 every time the imaging unit 22 captures an image.

[0040] S104: After the reference image is stored, the control unit 24 calculates the amount of deviation between the imaging range of the image captured by the imaging unit 22 (video camera 22A) and the imaging range of the reference image.

[0041] FIG. 5 is a schematic diagram for explaining the imaging range of an image. The imaging range R1 of the reference image at the time of installation shown in the left diagram of FIG. 5 may shift to the imaging range R2 due to a change in the posture of the support column 20A caused by some unintended factor after the operation of the roadside device 20. Unintended factors may include, for example, a collision of a vehicle or contact with a pedestrian as shown in FIG. 4, but the factors are not limited to these. When such a shift in the imaging range occurs, the detection accuracy of the pedestrian 4 may decrease. For example, in the example shown in FIG. 5, when the imaging range shifts to R2, the pedestrians 4 (a family of four people off by one) crossing the crosswalk 5 are outside the range of the imaging range R2 and cannot be detected.

[0042] S105: The control unit 24 determines whether or not the shift amount λ is equal to or greater than the threshold value X.

[0043] The shift amount λ is the ratio (%) obtained by dividing the area of the range where the imaging range R2 of the image captured by the imaging unit 22 does not overlap with the imaging range R1 of the reference image (the range where R2 is shifted from R1) by the area of the imaging range R1 of the reference image after the reference image is stored. The threshold value X is set to, for example, 20%, but the set value is not limited to 20%.

[0044] FIG. 6 is a schematic diagram for explaining the shift amount λ of the imaging range of an image. As shown in FIG. 6, it is assumed that the imaging range R1 of the reference image is shifted to the imaging range R2 due to some factor during the operation of the roadside device 20. In such a case, if the areas of the imaging ranges R1 and R2 are S1 and the area of the overlapping range of the imaging ranges R1 and R2 is S2, the shift amount λ (%) is calculated based on the following formula (1). λ = (S1 - S2) / S1 (1)

[0045] The control unit 24 determines whether or not the shift amount λ (%) is equal to or greater than the threshold value X (%) based on the following formula (2). λ ≥ X (2)

[0046] S106: When the shift amount λ is equal to or greater than the threshold value X, the control unit 24 notifies the server 30 of information prompting the restoration of the posture of the roadside device 20 via the notification unit 21.

[0047] Since the administrator of the server 30 that has received the notification can quickly recognize the change in the posture that has occurred in the roadside device 20, it is possible to quickly take measures such as returning the posture of the roadside device 20 to the reference posture. Further, each time the imaging unit 22 captures an image, the control unit 24 may temporarily store the captured image in the storage unit 23. When the deviation amount λ becomes equal to or greater than the threshold value X, the control unit 24 may transmit to the server 30 the image when the deviation amount λ becomes equal to or greater than the threshold value X and the image immediately before the deviation amount λ becomes equal to or greater than the threshold value X, so that the administrator of the server 30 can identify the cause of the deviation in the posture of the roadside device 20.

[0048] On the other hand, when the deviation amount λ is less than the threshold value X, the control unit 24 may continue to capture images by the imaging unit 22. Further, the control unit 24 may perform deviation correction of the captured image by image processing. By improving the accuracy of the captured image by deviation correction, the detection accuracy of the pedestrian 4 is further improved.

[0049] As described above, the roadside device 20 according to the present embodiment stores in the storage unit 23 a reference image captured by the imaging unit 22 in a state where the roadside device 20 is installed in the reference posture. After the reference image is stored, the control unit 24 calculates the deviation amount λ between the imaging range R2 of the image captured by the imaging unit 22 and the imaging range R1 of the reference image. When the deviation amount λ is equal to or greater than the threshold value X, the control unit 24 notifies the server 30 via the notification unit 21 of information prompting the restoration of the posture of the roadside device 20.

[0050] According to such a configuration, when the deviation amount λ between the imaging range R2 of the captured image and the imaging range R1 of the reference image is equal to or greater than the threshold value X, the roadside device 20 notifies the server 30 of information prompting the restoration of the posture of the roadside device 20. Since the administrator of the server 30 that has received the notification can quickly recognize the change in the posture that has occurred in the roadside device 20, it is possible to quickly take measures such as returning the posture of the roadside device 20 to the reference posture. Therefore, the technology for notifying the pedestrian 4 and the vehicle 10 of information is improved in terms of improving the detection accuracy of the pedestrian 4 heading toward the road lane 3.

[0051] Although the present disclosure has been described based on the drawings and examples, it should be noted that those skilled in the art may make various modifications and alterations based on the present disclosure. Therefore, it should be noted that these modifications and alterations are included in the scope of the present disclosure. For example, the functions etc. included in each component or each step etc. can be rearranged so as not to be logically contradictory, and it is possible to combine or divide a plurality of components or steps etc. into one.

[0052] For example, in the above-described embodiment, an embodiment in which the configuration and operation of the roadside device 20 are distributed to a plurality of computers capable of communicating with each other is also possible. Also, for example, an embodiment in which some or all of the constituent elements of the roadside device 20 are provided at a plurality of locations for each functional unit, and each functional unit is communicably connected to each other by wire or wirelessly is also possible. For example, the imaging unit 22, the notification unit 21, the storage unit 23, and the control unit 24 may be installed at different positions on the same column 20A, or may be distributed and installed on a plurality of columns 20A.

[0053] For example, in the above-described embodiment, it has been explained that when the posture of the column 20A changes from the basic posture due to an unintended factor such as a collision of a vehicle (motorcycle), the imaging range R1 of the video camera 22A shifts to R2 accordingly. However, the factors causing the shift of the imaging range R1 of the video camera 22A are not limited to this. Temporal changes in the mounting portion of the video camera 22A, or collisions of people, animals, or objects with the video camera 22A itself can also be factors causing the shift of the imaging range R1.

[0054] Also, for example, an embodiment in which a general-purpose computer functions as the roadside device 20 according to the above-described embodiment is also possible. Specifically, a program describing the processing contents for realizing each function of the roadside device 20 according to the above-described embodiment is stored in the memory of a general-purpose computer, and the program is read out and executed by a processor. Therefore, the present disclosure can also be realized as a program executable by a processor or a non-transitory computer-readable medium storing the program.

Description of Reference Numerals

[0055] 1 System 2 Network 3 Road lane 4 Pedestrian 5 Crosswalk 6 Roadside strip 7 Sidewalk 10 Vehicle (autonomous vehicle) 11 Communication unit 12 Output unit 13 Control unit 20 Roadside device 20A Pole 21 Notification unit 22 Imaging unit 22A Video camera 23 Memory unit 24 Control unit 30 Server (administrator's server) 31 Communication unit 32 Memory unit 33 Control unit

Claims

1. A roadside device comprising a notification unit, a photographing unit, a storage unit, and a control unit, wherein the control unit stores a reference image captured by the photographing unit in the storage unit in a state where the roadside device is installed in a reference posture, and after the reference image is stored, calculates a deviation amount between a photographing range of an image captured by the photographing unit and a photographing range of the reference image, and when the deviation amount is equal to or greater than a threshold value, notifies a server of information prompting restoration of the posture of the roadside device via the notification unit.

2. The roadside device according to claim 1, wherein the reference posture is a posture in which a support column supporting the roadside device faces in the vertical direction.

3. The roadside device according to claim 1, wherein the deviation amount is a ratio obtained by dividing an area of a range where the photographing range of an image captured by the photographing unit does not overlap with the photographing range of the reference image by the area of the photographing range of the reference image after the reference image is stored.

4. The roadside device according to claim 1, wherein the control unit continues to capture an image by the photographing unit when the deviation amount is less than the threshold value.

5. A notification method executed by a roadside device, storing a reference image captured in a state where the roadside device is installed in a reference posture; calculating a deviation amount between a photographing range of an image captured after the reference image is stored and a photographing range of the reference image; and when the deviation amount is equal to or greater than a threshold value, notifying a server of information prompting restoration of the posture of the roadside device. Including the above steps, the notification method.

Images