Radio wave sensor setting method, radio wave sensor setting device, and radio wave sensor

Abstract

A radio wave sensor setting method according to the present invention comprises: a step for acquiring, respectively from a first image sensor and a second image sensor, a first image and a second image each including a target area from which an object on a road is to be detected by a radio wave sensor; a step for determining a first identification point for identifying the target area in each of the acquired first image and second image; a step for converting a first image coordinate value, which is a coordinate value of the first identification point in a coordinate system of the first image, and a second image coordinate value, which is a coordinate value of the first identification point in a coordinate system of the second image, into a first sensor coordinate value that is a coordinate value of the first identification point in a coordinate system set for the radio wave sensor; and a step for setting a detection area which corresponds to the target area in the sensor coordinate system on the basis of the first sensor coordinate value.

Description

Radio wave sensor setting method, radio wave sensor setting device, and radio wave sensor

[0001] This application claims priority to Japanese Patent Application No. 2023-113925 filed on July 11, 2023, and incorporates by reference the entire contents of that application.

[0002] For the purpose of traffic monitoring, radio wave sensors are installed at positions where they can detect objects such as vehicles and pedestrians on roads (including intersections). Radio wave sensors installed in such infrastructure (road facilities) are used, for example, to measure the traffic volume of vehicles traveling on the road and to detect pedestrians on crosswalks. In order to use a radio wave sensor for traffic monitoring, it is necessary to set areas to be detected (hereinafter referred to as "detection areas"), such as roadways, lanes, crosswalks, and sidewalks, in the coordinate system of the radio wave sensor (see, for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2017-090078

[0004] A radio wave sensor setting method according to one aspect of the present disclosure includes the steps of acquiring a first image and a second image from a first image sensor and a second image sensor, respectively, the first image and the second image including a target area for object detection on a road by the radio wave sensor; determining a first specific point that identifies the target area in each of the acquired first image and the second image; converting first image coordinate values ​​that are the coordinate values ​​of the first specific point in a first image coordinate system, which is the coordinate system of the first image, and second image coordinate values ​​that are the coordinate values ​​of the first specific point in a second image coordinate system, which is the coordinate system of the second image, into first sensor coordinate values ​​that are the coordinate values ​​of the first specific point in a sensor coordinate system, which is a coordinate system set in the radio wave sensor; and setting a detection area corresponding to the target area in the sensor coordinate system based on the first sensor coordinate values.

[0005] FIG. 1 is a diagram illustrating an example of use of an infrastructure radio wave sensor according to an embodiment. FIG. 2 is a perspective view illustrating an example of the external configuration of an infrastructure radio wave sensor according to an embodiment. FIG. 3 is a block diagram illustrating an example of the hardware configuration of an infrastructure radio wave sensor according to an embodiment. FIG. 4 is a block diagram illustrating an example of the hardware configuration of a setting device according to an embodiment. FIG. 5 is a functional block diagram illustrating an example of functions of the setting device according to an embodiment. FIG. 6 is a diagram for explaining a stereo matching method. FIG. 7 is a diagram illustrating an example of a first specific point. FIG. 8 is a diagram for explaining conversion from coordinate values ​​of a first specific point in an intermediate coordinate system to coordinate values ​​of the first specific point in a sensor coordinate system. FIG. 9A is a diagram illustrating a first example of a display of a set detection area. FIG. 9B is a diagram illustrating a second example of a display of a set detection area. FIG. 10 is a diagram illustrating an example of a second specific point. FIG. 11 is a flowchart illustrating an example of an operation of the setting device according to an embodiment.

[0006] <Problem to be Solved by the Present Disclosure> In order to accurately detect pedestrians on a crosswalk, it is necessary to accurately set the detection area for the radio wave sensor. Conventionally, to set the detection area for a crosswalk, workers would measure the position of the crosswalk, the distance from the radio wave sensor, etc., or install reflectors on the crosswalk that can be detected by the radio wave sensor, but this work required a large number of people and was time-consuming.

[0007] Effect of the Present Disclosure According to the present disclosure, it is possible to reduce the burden on an operator required to set the detection area of ​​a radio wave sensor.

[0008] <Outline of Embodiments of the Present Disclosure> Below, an outline of embodiments of the present disclosure will be listed and described.

[0009] (1) A radio wave sensor setting method according to this embodiment includes the steps of acquiring, from a first image sensor and a second image sensor, a first image and a second image, respectively, including a target area for object detection on a road by the radio wave sensor; determining a first specific point in each of the acquired first and second images that identifies the target area; converting first image coordinate values, which are the coordinate values ​​of the first specific point in a first image coordinate system that is a coordinate system of the first image, and second image coordinate values, which are the coordinate values ​​of the first specific point in a second image coordinate system that is a coordinate system of the second image, into first sensor coordinate values, which are the coordinate values ​​of the first specific point in a sensor coordinate system that is a coordinate system set in the radio wave sensor; and setting a detection area corresponding to the target area in the sensor coordinate system based on the first sensor coordinate values. This allows the detection area to be set by determining the first specific point. This reduces the burden on an operator required to set the detection area of ​​the radio wave sensor.

[0010] (2) In the above (1), the determining step may determine the first image coordinate values ​​by accepting designation of the first image coordinate values ​​in the first image from a user. This allows the coordinate values ​​of a first specific point designated by the user in the first image to be determined as the first image coordinate values.

[0011] (3) In the above (2), the determining step may determine the second image coordinate values ​​by accepting designation of the second image coordinate values ​​in the second image from a user. This allows the coordinate values ​​of a first specific point designated by the user in the second image to be determined as the second image coordinate values.

[0012] (4) In the above (2), in the determining step, coordinate values ​​in the second image coordinate system corresponding to the determined first image coordinate values ​​may be identified by image processing on the second image, and the identified coordinate values ​​in the second image coordinate system may be determined as the second image coordinate values. In this way, if a user specifies the first image coordinate values, the second image coordinate values ​​can be determined by image processing on the second image, thereby reducing the burden on the user.

[0013] (5) In the above (1), in the determining step, the first image coordinate values ​​may be determined by recognizing the first specific point in the first image through image processing, and the second image coordinate values ​​may be determined by recognizing the first specific point in the second image through image processing. This allows the first image coordinate values ​​and the second image coordinate values ​​to be determined through image processing, thereby reducing the burden on the user.

[0014] (6) In any one of (1) to (5) above, the converting step may include a step of converting the first image coordinate values ​​and the second image coordinate values ​​into intermediate coordinate values ​​that are coordinate values ​​of the first specific point in an intermediate coordinate system that is a three-dimensional coordinate system formed by the first image and the second image, and a step of converting the intermediate coordinate values ​​into the first sensor coordinate values. The intermediate coordinate values ​​in the intermediate coordinate system can be determined by three-dimensional distance measurement from the parallax between the first image and the second image, and the first sensor coordinate values ​​can be determined from the intermediate coordinate values ​​based on the relative deviation amount (distance difference and angle difference) between the intermediate coordinate system and the sensor coordinate system.

[0015] (7) In any one of (1) to (6) above, the setting method may further include a step of determining whether the detection area set based on the first sensor coordinate values ​​is included in a radio wave irradiation area of ​​the radio wave sensor. If the detection area is not included in the radio wave irradiation area, objects within the detection area cannot be accurately detected. By determining whether the detection area is included in the radio wave irradiation area, it is possible to determine whether the detection area is an appropriate detection area.

[0016] (8) In any one of (1) to (7) above, the setting method may further include a step of superimposing and displaying the detection area set based on the first sensor coordinate values ​​and a radio wave irradiation area of ​​the radio wave sensor, thereby allowing a user to easily check whether the detection area is included in the radio wave irradiation area.

[0017] (9) In any one of (1) to (8) above, the setting method may further include the steps of: determining a second specific point in each of the first image and the second image, the second specific point specifying a non-target area including an object to be excluded from detection; converting third image coordinate values ​​that are coordinate values ​​of the second specific point in the first image coordinate system and fourth image coordinate values ​​that are coordinate values ​​of the second specific point in the second image coordinate system into second sensor coordinate values ​​that are coordinate values ​​of the second specific point in the sensor coordinate system; and setting an exclusion area in the sensor coordinate system that corresponds to the non-target area based on the second sensor coordinate values. This makes it possible to set an exclusion area that prevents stationary objects such as trees, buildings, and structures near the detection area from being mistaken for detection target objects such as vehicles and pedestrians.

[0018] (10) In any one of (1) to (9) above, the setting method may further include a step of adjusting an angle of at least one of the first image sensor and the second image sensor with respect to an antenna for transmitting and receiving radio waves included in the radio wave sensor, and in the step of acquiring the first image and the second image, the first image and the second image output from the first image sensor and the second image sensor, respectively, may be acquired after the angle of at least one of the first image sensor and the second image sensor is adjusted. This makes it possible to acquire the first image and the second image used for setting the detection area after adjusting the angle of the first image sensor and the second image sensor with respect to the antenna.

[0019] (11) In any one of (1) to (10) above, the setting method may further include changing a conversion parameter used to convert the first image coordinate values ​​and the second image coordinate values ​​into the first sensor coordinate values, depending on an adjustment amount of the angles of the first image sensor and the second image sensor relative to the antenna. This makes it possible to obtain appropriate first sensor coordinate values ​​when the angles of the first image sensor and the second image sensor relative to the antenna are adjusted.

[0020] (12) A radio wave sensor setting device according to this embodiment includes: an acquisition unit that acquires, from a first image sensor and a second image sensor, first and second images including a target area for object detection on a road by the radio wave sensor; a determination unit that determines a first specific point that identifies the target area in each of the first and second images acquired by the acquisition unit; a conversion unit that converts first image coordinate values ​​that are the coordinate values ​​of the first specific point in a first image coordinate system, which is a coordinate system of the first image, and second image coordinate values ​​that are the coordinate values ​​of the first specific point in a second image coordinate system, which is a coordinate system of the second image, into first sensor coordinate values ​​that are the coordinate values ​​of the first specific point in a sensor coordinate system, which is a coordinate system set in the radio wave sensor; and a setting unit that sets a detection area corresponding to the target area in the sensor coordinate system based on the first sensor coordinate values. This allows the detection area to be set by determining the first specific point. This reduces the burden on an operator required to set the detection area of ​​the radio wave sensor.

[0021] (13) A radio wave sensor according to this embodiment includes an antenna that transmits radio waves to an area on a road and receives waves reflected by an object within the area, a detection circuit that detects the position of the object based on the reflected waves received by the antenna, a housing that accommodates the antenna and the detection circuit, and mounting portions provided on the housing for mounting a first image sensor and a second image sensor, respectively. This allows the first image sensor and the second image sensor used to define the detection area to be mounted on the housing.

[0022] (14) In the above (13), the mounting portion may include an angle adjustment mechanism for adjusting angles of the first image sensor and the second image sensor relative to the antenna, thereby making it possible to adjust the angles of the first image sensor and the second image sensor relative to the antenna.

[0023] The present disclosure can be realized not only as a radio wave sensor setting method having the above-described characteristic processes as steps, but also as a radio wave sensor setting device having a characteristic configuration, or as a radio wave sensor having a characteristic configuration. Furthermore, the present disclosure can be realized as a computer program for causing a setting device to execute the characteristic processes, or as a semiconductor integrated circuit as part or all of the radio wave sensor setting device, or as a system including the radio wave sensor setting device.

[0024] <Details of Embodiments of the Present Disclosure> Hereinafter, details of embodiments of the present disclosure will be described with reference to the drawings. Note that at least some of the embodiments described below may be combined in any manner.

[0025] 1 is a diagram showing an example of use of an infrastructure radio wave sensor according to an embodiment. The infrastructure radio wave sensor 10 according to this embodiment is a radio wave radar for traffic monitoring, and detects objects (pedestrians, bicycles (including riders), and vehicles) on a crosswalk 20. The infrastructure radio wave sensor 10 is, for example, a millimeter-wave radar.

[0026] The infrastructure radio wave sensor 10 is attached to a structure 50 provided on a road. The structure 50 is several meters tall, and the infrastructure radio wave sensor 10 is installed several meters above the ground. The structure 50 includes, for example, a pole 51 and an arm 52 provided near the top end of the pole 51, and the infrastructure radio wave sensor 10 is attached to the arm 52.

[0027] The infrastructure radio wave sensor 10 emits radio waves (millimeter waves) onto the crosswalk 20 and receives the reflected waves to detect an object (e.g., a pedestrian or a bicycle) on the crosswalk 20. More specifically, the infrastructure radio wave sensor 10 can detect the distance from the infrastructure radio wave sensor 10 to the object on the crosswalk 20, the speed of the object (the speed in the straight line connecting the infrastructure radio wave sensor 10 and the object), and the horizontal angle (azimuth angle) of the position of the object relative to the radio wave emission axis.

[0028] The infrastructure radio wave sensor 10 sets a detection area 30, which is a range on the road in which to detect objects. The detection area 30 is set as part of a radio wave irradiation area 40 of the infrastructure radio wave sensor 10. In other words, the radio wave irradiation area 40 covers the detection area 30. In order for the infrastructure radio wave sensor 10 to monitor the traffic conditions across the entire crosswalk 20, the detection area 30 may be set to include the entire crosswalk 20. Note that the radio wave irradiation area 40 is a range in which an object reflects the radio waves irradiated by the infrastructure radio wave sensor 10 and the infrastructure radio wave sensor 10 can detect the object based on the reflected waves from the object, and does not include a range in which the infrastructure radio wave sensor 10 cannot detect an object even if it can irradiate radio waves. However, the radio wave irradiation area 40 is not limited to this and may be the entire range in which the infrastructure radio wave sensor 10 can irradiate radio waves.

[0029] For example, the infrastructure radio wave sensor 10 used to measure the number of pedestrians and bicycles (hereinafter also referred to as "pedestrians") crossing the crosswalk 20 or to control traffic signals installed at the crosswalk 20 is required to detect not only pedestrians on the crosswalk but also pedestrians waiting to cross on the sidewalk adjacent to the crosswalk 20. For this reason, for example, the detection area 30 includes not only the area of ​​the crosswalk 20 but also an area on the sidewalk where pedestrians wait to cross. In other words, the detection area 30 is an area extending from the crosswalk 20 on both sides in the longitudinal direction of the crosswalk (the direction in which pedestrians walk on the crosswalk).

[0030] A coordinate space for detecting objects is set in the infrastructure radio wave sensor 10. Hereinafter, the coordinate system set in the infrastructure radio wave sensor 10 is also referred to as the "sensor coordinate system." For example, the sensor coordinate system is a Cartesian coordinate system with an origin at a point on the ground vertically below the infrastructure radio wave sensor 10, two mutually orthogonal horizontal axes as the X-axis and Y-axis, and a vertical axis passing through the origin as the Z-axis. For example, the Y-axis is an intersection line between a vertical plane relative to the ground and the ground, which includes the radio wave irradiation axis of the infrastructure radio wave sensor 10 (the normal to the radio wave irradiation surface of the infrastructure radio wave sensor 10). Hereinafter, the direction of this intersection line is also referred to as the "radio wave irradiation direction." The X-axis is an axis perpendicular to the Y-axis and parallel to the ground. The Z-axis is an axis perpendicular to the X-axis and Y-axis and perpendicular to the ground.

[0031] In order for the infrastructure radio wave sensor 10 to accurately detect an object on the crosswalk 20, it is necessary to accurately set a detection area 30 in the coordinate space of the sensor coordinate system (hereinafter also referred to as the "sensor coordinate space"). In this embodiment, the setting device determines the detection area 30 in the sensor coordinate space of the infrastructure radio wave sensor 10.

[0032] 2. Hardware Configuration of the Infrastructure Radio Wave Sensor FIG. 2 is a perspective view showing an example of the external configuration of the infrastructure radio wave sensor 10 according to the embodiment. As shown in FIG. 2, the infrastructure radio wave sensor 10 includes a housing 140 having a transmitting / receiving surface 140a on one surface for transmitting and receiving radio waves. The housing 140 houses a transmitting / receiving unit 104 and a detection circuit 120. The transmitting / receiving unit 104 includes a transmitting antenna 105a and multiple (e.g., four) receiving antennas 106a. The infrastructure radio wave sensor 10 transmits modulated waves, which are radio waves, from the transmitting antenna 105a through the transmitting / receiving surface 140a. The modulated waves hit an object and are reflected, and the receiving antenna 106a receives the reflected waves. The receiving antenna 106a is an example of an "antenna." The transmitting / receiving unit 104 and the detection circuit 120 perform signal processing on the transmitted wave signal and the received wave signal to detect the distance to the object, the speed of the object, and the azimuth angle at which the object is located.

[0033] The housing 140 of the infrastructure radio wave sensor 10 according to this embodiment is provided with a first mounting portion 141 for mounting the first image sensor 131 and a second mounting portion 142 for mounting the second image sensor 132. The first mounting portion 141 is provided on a first side surface of the housing 140 (in the example of FIG. 2 , the right side surface as viewed in the direction of radio wave emission), and the second mounting portion 142 is provided on a second side surface of the housing 140 (in the example of FIG. 2 , the left side surface as viewed in the direction of radio wave emission).

[0034] The first image sensor 131 is built into a first imaging device 131A such as a smartphone or a camera, and the second image sensor 132 is built into a second imaging device 132A such as a smartphone or a camera. The first attachment portion 141 is capable of holding the first imaging device 131A, and the second attachment portion 142 is capable of holding the second imaging device 132A. That is, the first attachment portion 141 holds the first imaging device 131A, thereby attaching the first image sensor 131 to the first attachment portion 141. The second attachment portion 142 holds the second imaging device 132A, thereby attaching the second image sensor 132 to the second attachment portion 142.

[0035] The first mounting portion 141 and the second mounting portion 142 are configured so that the first image sensor 131 of the first imaging device 131A mounted on the first mounting portion 141 and the second image sensor 132 of the second imaging device 132A mounted on the second mounting portion 142 face the same direction. In other words, when the first imaging device 131A is mounted on the first mounting portion 141 and the second imaging device 132A is mounted on the second mounting portion 142, the fields of view of the first image sensor 131 and the second image sensor 132 include the same object. For example, if the field of view of the first image sensor 131 includes the pedestrian crossing 20, the field of view of the second image sensor 132 also includes the pedestrian crossing 20.

[0036] For example, the first mounting portion 141 includes an angle adjustment mechanism having, for example, a rotating shaft and a bearing, and is configured to be able to adjust the angle with respect to the housing 140 (i.e., with respect to the transmitting antenna 105a and the receiving antenna 106a). Similarly, the second mounting portion 142 includes an angle adjustment mechanism having, for example, a rotating shaft and a bearing, and is configured to be able to adjust the angle with respect to the housing 140.

[0037] More specifically, the first mounting portion 141 and the second mounting portion 142 are linked together. That is, the angle of the first mounting portion 141 relative to the housing 140 is adjusted by the same amount as the angle adjustment amount of the first mounting portion 141 relative to the housing 140. As a result, the relative angle of the first image sensor 131 relative to the housing 140 and the relative angle of the second image sensor 132 relative to the housing 140 are always the same.

[0038] The first mounting portion 141 and the second mounting portion 142 may be rotatable independently of each other. In this case, the angle of the first mounting portion 141 and the angle of the second mounting portion 142 are adjusted independently. For example, the worker may adjust the angles of the first mounting portion 141 and the second mounting portion 142 individually so that the first image sensor 131 of the first imaging device 131A attached to the first mounting portion 141 and the second image sensor 132 of the second imaging device 132A attached to the second mounting portion 142 face in the same direction.

[0039] The infrastructure radio wave sensor 10 includes an angle sensor 141A. The angle sensor 141A detects the angle adjustment amount of the first attachment portion 141.

[0040] 3 is a block diagram showing an example of the hardware configuration of the infrastructure radio wave sensor 10 according to the embodiment. The infrastructure radio wave sensor 10 includes a transmitting / receiving unit 104 and a detection circuit 120.

[0041] The detection circuit 120 includes a processor 101, a non-volatile memory 102, a volatile memory 103, a communication interface 107, and an input / output interface 108.

[0042] The transmitting / receiving unit 104 includes a transmitting circuit 105 and a receiving circuit 106 .

[0043] The transmission circuit 105 includes a transmission antenna 105a. The number of transmission antennas 105a is not limited to one, and may be multiple. The transmission circuit 105 generates a modulated wave and transmits the generated modulated wave from the transmission antenna 105a.

[0044] The receiving circuit 106 includes a receiving antenna 106a. Multiple (four in the figure) receiving antennas 106a are provided to detect the azimuth angle of an object. The receiving circuit 106 performs signal processing on the received reflected waves. The reflected wave data generated by the signal processing is provided to the processor 101. The processor 101 analyzes the reflected wave data to detect the position (distance and azimuth angle) and speed of the object.

[0045] The volatile memory 103 is a semiconductor memory such as an SRAM (Static Random Access Memory) or a DRAM (Dynamic Random Access Memory). The non-volatile memory 102 is a flash memory, a hard disk, a ROM (Read Only Memory), or the like. The non-volatile memory 102 stores a control program 110, which is a computer program, and data used to execute the control program 110. The functions of the infrastructure radio wave sensor 10 are realized when the processor 101 executes the control program 110. The control program 110 can be stored in a recording medium such as a flash memory, a ROM, or a CD-ROM. The processor 101 can detect the position (distance and azimuth) and speed of an object using the control program 110.

[0046] The processor 101 is, for example, a CPU (Central Processing Unit). However, the processor 101 is not limited to a CPU. The processor 101 may also be a GPU (Graphics Processing Unit). The processor 101 may also be, for example, an ASIC (Application Specific Integrated Circuit) or a programmable logic device such as an FPGA (Field Programmable Gate Array). In this case, the ASIC or programmable logic device is configured to be able to execute the same processing as the control program 110.

[0047] The communication interface 107 can communicate with external devices. The communication interface 107 is connected to the setting device 200 (see FIG. 4) by wire and can transmit data of the detection result (hereinafter also referred to as "detection data") to the setting device 200. The communication interface 107 is a wireless communication interface and may be able to communicate with the setting device 200 wirelessly.

[0048] The nonvolatile memory 102 stores setting information 111 for the detection area 30. The setting information 111 includes position information of the detection area 30 in the sensor coordinate space.

[0049] The input / output interface 108 is connected to the first imaging device 131A and the second imaging device 132A. The input / output interface 108 receives an input of an image (first image) output from the first imaging device 131A, and receives an input of an image (second image) output from the second imaging device 132A.

[0050] Furthermore, the input / output interface 108 is connected to an angle sensor 141 A. The input / output interface 108 receives the detection value of the angle adjustment amount of the first attachment portion 141 and the second attachment portion 142 output from the angle sensor 141 A.

[0051] 4 is a block diagram showing an example of the hardware configuration of a setting device according to an embodiment. The setting device 200 according to this embodiment is used to set the detection area 30 of the infrastructure radio wave sensor 10. The setting device 200 includes a processor 201, a non-volatile memory 202, a volatile memory 203, an input / output interface 204, a graphics controller 205, and a communication interface 206. The setting device 200 further includes an input device 211 and a display device 212. Note that at least one of the input device 211 and the display device 212 may be an external device connected to the setting device 200.

[0052] The volatile memory 203 is, for example, a semiconductor memory such as an SRAM or a DRAM. The non-volatile memory 202 is, for example, a flash memory, a hard disk, a ROM, or the like. The non-volatile memory 202 stores a setting program 210, which is a computer program, and data used to execute the setting program 210. The functions of the setting device 200 are realized when the setting program 210 is executed by the processor 201. The setting program 210 can be stored in a recording medium such as a flash memory, a ROM, or a CD-ROM. The processor 201 sets the detection area 30 of the infrastructure radio wave sensor 10 using the setting program 210.

[0053] The processor 201 is, for example, a CPU. However, the processor 201 is not limited to a CPU. The processor 201 may be a GPU. The processor 201 may be, for example, an ASIC or a programmable logic device such as an FPGA. In this case, the ASIC or programmable logic device is configured to be able to execute the same processing as the setting program 210.

[0054] For example, the input device 211 includes a keyboard and a pointing device such as a mouse. The input device 211 may be a capacitive or pressure-sensitive touchpad overlaid on the screen of the display device 212. The input device 211 is used to input data to the setting device 200. The input / output interface 204 is connected to the input device 211. The input / output interface 204 receives input data from the input device 211 and provides the received data to the processor 201.

[0055] The display device 212 includes, for example, a liquid crystal panel or an OEL (organic electroluminescence) panel. The display device 212 can display text or graphic information. The graphics controller 205 is connected to the display device 212 and controls the display on the display device 212. The graphics controller 205 includes, for example, a GPU and a VRAM (Video RAM), stores data to be displayed on the display device 212 in the VRAM, periodically reads one frame of video data from the VRAM, and generates a video signal. The generated video signal is output to the display device 212, and the video is displayed on the display device 212. The function of the graphics controller 205 may be included in the processor 201. A portion of the area of ​​the volatile memory 203 may be used as the VRAM.

[0056] The communication interface 206 can communicate with an external device. For example, the communication interface 206 is connected to the infrastructure radio wave sensor 10 via a communication cable, and can communicate with the infrastructure radio wave sensor 10. The communication interface 206 may be a wireless communication interface and can communicate with the infrastructure radio wave sensor 10 wirelessly.

[0057] 4. Functions of the Infrastructure Radio Wave Sensor The infrastructure radio wave sensor 10 has an object detection function as described below, as a result of the processor 101 executing the control program 110 .

[0058] The infrastructure radio wave sensor 10 detects the position and speed of an object based on the reflected waves that are generated when radio waves are irradiated onto the object and reflected by the object.

[0059] Specifically, the infrastructure radio wave sensor 10 generates reflected wave data that indicates information including the signal level of the reflected wave for each position where the radio wave is irradiated. The transmission circuit 105 transmits a transmission signal, which is a modulated wave, from the transmission antenna 105a. The transmission signal from the transmission antenna 105a is reflected by an object. The receiving antenna 106a receives the reflected wave from the object. The detection circuit 120 combines the modulated wave signal output from the transmission circuit 105 with the reflected wave signal output from the receiving circuit 106 to generate an intermediate frequency signal (hereinafter referred to as an "IF signal"). The detection circuit 120 performs a fast Fourier transform (FFT) on the IF signal to obtain information on distance, speed, and azimuth angle. The detection circuit 120 generates reflected wave data based on the obtained distance and azimuth angle information.

[0060] The detection circuit 120 extracts reflection points, which are peak points included in the reflected wave data. The reflected wave data includes data indicating the waveform of the reflected wave for distance and data indicating the waveform of the reflected wave for angle. The detection circuit 120 extracts peak points from each of the waveform of the reflected wave for distance and the waveform of the reflected wave for angle. The detection circuit 120 determines the reflection points by associating the peak points in the reflected wave for distance with the peak points in the reflected wave for angle.

[0061] Radio waves emitted from the infrastructure radio wave sensor 10 may be reflected by multiple objects simultaneously. The detection circuit 120 groups reflection points on the same object. The detection circuit 120 identifies the position of the object based on the reflected waves received by the receiving antenna 106a. The position of the object is expressed as a coordinate value in the sensor coordinate system. Specifically, the detection circuit 120 determines a representative value of the reflection points belonging to the same group and sets the determined representative value as the position of the object. For example, the representative value is the center of gravity. However, the position of the object may also be a representative value other than the center of gravity of the multiple reflection points. For example, the representative value may be the average value of the reflection points or the median value of the reflection points.

[0062] A transmission signal (chirp) is transmitted from the transmitting antenna 105a at regular intervals. A moving object reflects the transmission signal at two different points, and the receiving antenna 106a receives each reflected wave. The detection circuit 120 detects the speed of the moving object from the phase difference between multiple IF signals obtained from the object.

[0063] The detection circuit 120 tracks detected objects. Specifically, the detection circuit 120 assigns an ID to each detected object. The detection circuit 120 outputs detection results of the object's position and speed at regular time intervals. The detection circuit 120 identifies currently detected objects that are the same as the previously detected object. For example, the detection circuit 120 estimates the current position of object a based on the previous movement direction and speed of object a. The detection circuit 120 identifies the currently detected object that is closest to the position estimated from the previous movement direction and speed of object a as object a. An object identified as the same as the previously detected object inherits the ID of the previously detected object.

[0064] The detection circuit 120 outputs the result of object detection by the infrastructure radio wave sensor 10. The detection result includes the object's position (distance and azimuth), speed, ID, and time information indicating the detection time. The detection circuit 120 outputs the object detection result at regular time intervals.

[0065] 5 is a functional block diagram showing an example of functions of the setting device according to the embodiment. When the processor 201 executes the setting program 210, the setting device 200 functions as an acquisition unit 221, a first determination unit 222, a first conversion unit 223, a first setting unit 224, a display control unit 225, a first determination unit 226, a parameter change unit 227, a second determination unit 228, a second determination unit 229, a second conversion unit 230, and a second setting unit 231.

[0066] The infrastructure radio wave sensor 10 is attached to the structure 50. When attaching the infrastructure radio wave sensor 10 to the structure 50, the worker adjusts the attachment angle of the infrastructure radio wave sensor 10 so that the transmitting and receiving surface 140a faces the area where object detection is to be performed, for example, the crosswalk 20.

[0067] Once the infrastructure radio wave sensor 10 is attached to the structure 50, the worker performs the work of setting the detection area 30. First, the worker attaches the first imaging device 131A to the first mounting portion 141 of the infrastructure radio wave sensor 10, and attaches the second imaging device 132A to the second mounting portion 142. At this time, the worker adjusts the angles of the first mounting portion 141 and the second mounting portion 142 so that the crosswalk 20 is included in the field of view of the first image sensor 131 and the field of view of the second image sensor 132.

[0068] For example, the first image sensor 131 and the second image sensor 132 output images synchronously, i.e., the first image sensor 131 outputs a first image and the second image sensor 132 outputs a second image at the same time.

[0069] The acquisition unit 221 acquires the first image and the second image from the first image sensor 131 and the second image sensor 132, respectively. In a specific example, the first image is output from the first imaging device 131A to the infrastructure radio wave sensor 10, and the second image is output from the second imaging device 132A to the infrastructure radio wave sensor 10. The infrastructure radio wave sensor 10 transmits each of the first image and the second image to the setting device 200. The acquisition unit 221 acquires the first image and the second image by receiving them. In another example, the first imaging device 131A may directly transmit the first image to the setting device 200, and the second imaging device 132A may directly transmit the second image to the setting device 200. The acquisition unit 221 can acquire the first image and the second image by receiving the first image transmitted from the first imaging device 131A and the second image transmitted from the second imaging device 132A.

[0070] Each of the first image and the second image acquired by the acquisition unit 221 includes a crosswalk 20 (target area) that is the target of object detection on the road.

[0071] The first and second images are obtained by capturing images of the same object from different fields of view, and the position of the captured object in three-dimensional coordinate space can be identified by stereo matching using the first and second images.

[0072] 6 is a diagram for explaining the stereo matching method. The first image sensor 131 and the second image sensor 132 output a first image 301 and a second image 302 of a field of view including the same object OB, respectively.

[0073] An image coordinate system (first image coordinate system and second image coordinate system) is defined for each of the first image 301 and the second image 302. The image coordinate system is a two-dimensional Cartesian coordinate system with the upper left corner of the image as the origin and configured with a first axis with the right direction being positive and a second axis with the downward direction being positive. Hereinafter, the first axis in the first image 301 is defined as x_R and the second axis is defined as y_R. The first axis in the second image 302 is defined as x_L and the second axis is defined as y_L.

[0074] A first image 301 captured by the first image sensor 131 includes a point P_R, which is an image of the object OB. A second image 302 captured by the second image sensor 132 includes a point P_L, which is an image of the object OB. The coordinate value of the point P_R in the first image coordinate system (x_R, y_R) and the coordinate value of the point P_L in the second image coordinate system (x_L, y_L) are determined according to the distance (parallax) between the first image sensor 131 and the second image sensor 132.

[0075] In the stereo matching method, the coordinate values ​​of the target OB in a three-dimensional coordinate system (x, y, z) are identified based on the coordinate values ​​of the point P_R in the first image coordinate system (x_R, y_R) and the coordinate values ​​of the point P_L in the second image coordinate system (x_L, y_L). In other words, in the stereo matching method, the coordinate values ​​of the point P_R in the first image coordinate system (x_R, y_R) and the coordinate values ​​of the point P_L in the second image coordinate system (x_L, y_L) are converted into coordinate values ​​of the target OB in the three-dimensional coordinate system (x, y, z). The three-dimensional coordinate system (x, y, z) is a three-dimensional coordinate system formed by the first image 301 and the second image 302, and hereinafter this three-dimensional coordinate system will also be referred to as an "intermediate coordinate system."

[0076] Returning to FIG. 5, the first determination unit 222 determines a first specific point that identifies the crosswalk 20 in each of the acquired first and second images.

[0077] For example, the first specific points are the four vertices of a quadrangular crosswalk. However, the number of first specific points is not limited to 4. For example, if the crosswalk is a polygon having n vertices (an n-gon), the first specific points are each of the n vertices.

[0078] Fig. 7 is a diagram showing an example of a first specific point. In Fig. 7, the crosswalk 20 is a rectangle. Therefore, the first specific points of the crosswalk 20 are its four vertices. The first image 301 includes an image 20_1 of the crosswalk 20, and the second image 302 includes an image 20_2 of the crosswalk 20. Because the first image 301 and the second image 302 are images in different fields of view, the images 20_1 and 20_2 are rectangles with different shapes.

[0079] In the first image 301, the first specific points of the crosswalk 20 correspond to the vertices p11, p12, p13, and p14 of the rectangular image 20_1. Therefore, the coordinate values ​​of the first specific points in the first image coordinate system (x_R, y_R) (hereinafter also referred to as "first image coordinate values") are p11 (x11_R, y11_R), p12 (x12_R, y12_R), p13 (x13_R, y13_R), and p14 (x14_R, y14_R).

[0080] In the second image 302, the first specific point of the crosswalk 20 corresponds to the vertices p21, p22, p23, and p24 of the rectangular image 20_2. Therefore, the coordinate values ​​of the first specific point in the second image coordinate system (x_L, y_L) (hereinafter also referred to as "second image coordinate values") are p21 (x21_L, y21_L), p22 (x22_L, y22_L), p23 (x23_L, y23_L), and p24 (x24_L, y24_L).

[0081] The first determination unit 222 determines first image coordinate values ​​p11 (x11_R, y11_R), p12 (x12_R, y12_R), p13 (x13_R, y13_R), and p14 (x14_R, y14_R) of the first specific point in such a first image 301, and determines second image coordinate values ​​p21 (x21_L, y21_L), p22 (x22_L, y22_L), p23 (x23_L, y23_L), and p24 (x24_L, y24_L) of the first specific point in the second image coordinate system (x_L, y_L).

[0082] In a specific example, the first determination unit 222 determines the first image coordinate values ​​by accepting a user's designation of the first image coordinate values ​​in the first image 301. For example, each of the first image 301 and the second image 302 is displayed on the display device 212. Points on the first image 301 and the second image 302 displayed on the screen can be designated by the input device 211. Specifically, the user can designate points on the first image 301 and the second image 302 displayed on the touch panel by touching them. The user designates the first image coordinate values ​​p11 (x11_R, y11_R), p12 (x12_R, y12_R), p13 (x13_R, y13_R), and p14 (x14_R, y14_R) of the first specific point by touching the four corners of the image 20_1 of the crosswalk 20 in the displayed first image 301. The first determination unit 222 receives coordinate values ​​designated by the user, and determines the designated coordinate values ​​as first image coordinate values ​​of the first specific point.

[0083] In a more specific example, the first determination unit 222 determines the second image coordinate values ​​by accepting designation from the user of second image coordinate values ​​in the second image 302. For example, the user touches four corners of the image 20_2 of the crosswalk 20 in the displayed second image 302 to specify second image coordinate values ​​p21 (x21_L, y21_L), p22 (x22_L, y22_L), p23 (x23_L, y23_L), and p24 (x24_L, y24_L) of the first specific point. The first determination unit 222 accepts the designation of the coordinate values ​​from the user and determines the specified coordinate values ​​as the second image coordinate values ​​of the first specific point.

[0084] A pattern for specifying the first image coordinate values ​​of the first specific points in the first image 301 and the second image coordinate values ​​of the first specific points in the second image 302 may be determined in advance. For example, a pattern may be determined in which four first specific points in the first image 301 are specified in clockwise order from the top left first specific point, and four first specific points in the second image 302 are specified in clockwise order from the top left first specific point. In a more specific example, a pattern may be determined in which the first specific points in the first image 301 and the first specific points in the second image 302 are specified alternately. That is, the user designates a first specific point p11 at the upper left in the first image 301, a first specific point p21 at the upper left in the second image 302, a first specific point p12 at the upper right in the first image 301, a first specific point p22 at the upper right in the second image 302, a first specific point p13 at the lower right in the first image 301, a first specific point p23 at the lower right in the second image 302, a first specific point p14 at the lower left in the first image 301, and a first specific point p24 at the lower left in the second image 302. This allows the first determination unit 222 to easily recognize corresponding points in the images 20_1 and 20_2.

[0085] However, the method for determining the first image coordinate values ​​of the first specific point in the first image 301 and the second image coordinate values ​​of the first specific point in the second image 302 is not limited to the above. For example, the first determination unit 222 may determine coordinate values ​​in the second image coordinate system corresponding to the determined first image coordinate values ​​by performing image processing on the second image 302, and determine the determined coordinate values ​​in the second image coordinate system as the second image coordinate values.

[0086] 6 , when the first image sensor 131 and the second image sensor 132 are aligned horizontally, the coordinate values ​​of the second axes y_R and y_L of a point P_R, which is an image of the target OB in the first image 301, and a point P_L, which is an image of the target OB in the second image 302, generally coincide with each other. Therefore, when the first image coordinate values ​​of the first specific point in the first image 301 are determined, the first specific point in the second image 302 can be recognized by image processing based on the determined first image coordinate values. Specifically, a range in which the coordinate values ​​of the second axis y_L in the second image 302 are close to the coordinate values ​​of the second axis y_L of the first specific point in the first image 301 (for example, a predetermined range centered on the coordinate value of the second axis y_L of the first specific point in the first image 301) is determined as the search range. An image of the surroundings of the first specific point is extracted from the first image 301, and pattern matching is performed between the extracted image and the image of the search range in the second image 302, and the coordinate value of the point with the highest similarity can be determined as point P_L, which is the image of the target OB in the second image 302.

[0087] Returning to Figure 7, the first determination unit 222 performs the image processing described above using each of the surrounding images of the first specific points p11, p12, p13, and p14 in the first image 301, thereby being able to determine the second coordinate values ​​p21 (x21_L, y21_L), p22 (x22_L, y22_L), p23 (x23_L, y23_L), and p24 (x24_L, y24_L) of the first specific points p21, p22, p23, and p24 in the second image 302.

[0088] As yet another example, the first determination unit 222 may perform image processing on each of the first image 301 and the second image 302, and recognize a first specific point in the first image 301 and a first specific point in the second image 302. In a specific example, image features of a corner of a pedestrian crossing are stored, and a portion in the first image 301 that matches the feature is recognized as the first specific point, and a portion in the second image 302 that matches the feature is recognized as the first specific point. This allows the first determination unit 222 to determine the first image coordinate value of the first specific point in the first image 301 and the second image coordinate value of the first specific point in the second image 302 without user designation.

[0089] Returning to Figure 5, the first conversion unit 223 converts the first image coordinate values, which are the coordinate values ​​of the first specific point in the first image coordinate system of the first image 301, and the second image coordinate values, which are the coordinate values ​​of the first specific point in the second image coordinate system of the second image 302, into first sensor coordinate values, which are the coordinate values ​​of the first specific point in the sensor coordinate system set in the infrastructure radio wave sensor 10.

[0090] In a specific example, the first conversion unit 223 converts the first image coordinate values ​​and the second image coordinate values ​​into coordinate values ​​(intermediate coordinate values) of a first specific point in an intermediate coordinate system, which is a three-dimensional coordinate system formed by the first image 301 and the second image 302.

[0091] That is, the first conversion unit 223 converts the first image coordinate value of the first specific point in the first image 301 and the second image coordinate value of the first specific point in the second image 302 into the coordinate value of the first specific point in the intermediate coordinate system using a stereo matching method.

[0092] 7 , a first specific point p11 in the first image 301 corresponds to a first specific point p21 in the second image 302. A first specific point p12 in the first image 301 corresponds to a first specific point p22 in the second image 302. A first specific point p13 in the first image 301 corresponds to a first specific point p23 in the second image 302. A first specific point p14 in the first image 301 corresponds to a first specific point p24 in the second image 302. The first conversion unit 223 converts the first image coordinate values ​​(x11_R, y11_R) of the first specific point p11 and the second image coordinate values ​​(x21_L, y21_L) of the first specific point p21, which correspond to each other, into coordinate values ​​(x1, y1, z1) of the first specific point p1 in the intermediate coordinate system (x, y, z). The first conversion unit 223 converts the first image coordinate values ​​(x12_R, y12_R) of the corresponding first specific point p12 and the second image coordinate values ​​(x22_L, y22_L) of the corresponding first specific point p22 into coordinate values ​​(x2, y2, z2) of the first specific point p2 in the intermediate coordinate system (x, y, z). The first conversion unit 223 converts the first image coordinate values ​​(x13_R, y13_R) of the corresponding first specific point p13 and the second image coordinate values ​​(x23_L, y23_L) of the corresponding first specific point p23 into coordinate values ​​(x3, y3, z3) of the first specific point p3 in the intermediate coordinate system (x, y, z). The first conversion unit 223 converts the first image coordinate values ​​(x14_R, y14_R) of the corresponding first specific point p14 and the second image coordinate values ​​(x24_L, y24_L) of the corresponding first specific point p24 into the coordinate values ​​(x4, y4, z4) of the first specific point p4 in the intermediate coordinate system (x, y, z).

[0093] Returning to FIG. 5, the first conversion unit 223 converts the intermediate coordinate values ​​of the first specific point in the intermediate coordinate system into coordinate values ​​of the first specific point in the sensor coordinate system (first sensor coordinate values).

[0094] FIG. 8 is a diagram for explaining conversion from the coordinate values ​​of the first specific point in the intermediate coordinate system to the coordinate values ​​of the first specific point in the sensor coordinate system.

[0095] The intermediate coordinate system (x, y, z) and the sensor coordinate system (X, Y, Z) are different coordinate systems. Therefore, in order to use the position of the crosswalk 20 identified by the first image sensor 131 and the second image sensor 132 to set the detection area 30, the coordinate values ​​of the crosswalk 20 in the intermediate coordinate system must be converted into coordinate values ​​in the sensor coordinate system.

[0096] Specifically, the first conversion unit 223 converts the intermediate coordinate values ​​into sensor coordinate values ​​for each first specific point. That is, the first conversion unit 223 converts the coordinate values ​​(x1, y1, z1) of the first specific point p1 in the intermediate coordinate system (x, y, z) into the coordinate values ​​(X1, Y1, Z1) of the first specific point P1 in the sensor coordinate system (X, Y, Z). The first conversion unit 223 converts the coordinate values ​​(x2, y2, z2) of the first specific point p2 in the intermediate coordinate system (x, y, z) into the coordinate values ​​(X2, Y2, Z2) of the first specific point P2 in the sensor coordinate system (X, Y, Z). The first conversion unit 223 converts the coordinate values ​​(x3, y3, z3) of the first specific point p3 in the intermediate coordinate system (x, y, z) into coordinate values ​​(X3, Y3, Z3) of the first specific point P3 in the sensor coordinate system (X, Y, Z). The first conversion unit 223 converts the coordinate values ​​(x4, y4, z4) of the first specific point p4 in the intermediate coordinate system (x, y, z) into coordinate values ​​(X4, Y4, Z4) of the first specific point P4 in the sensor coordinate system (X, Y, Z).

[0097] The relative positional relationship between the intermediate coordinate system (x, y, z) and the sensor coordinate system (X, Y, Z) is determined by the relative positional relationship between the first image sensor 131 and the second image sensor 132 and the transmitting antenna 105 a and the receiving antenna 106 a. Therefore, for coordinate transformation from the intermediate coordinate system (x, y, z) to the sensor coordinate system (X, Y, Z), transformation parameters determined from the relative positional relationship between the first image sensor 131 and the second image sensor 132 and the transmitting antenna 105 a and the receiving antenna 106 a are used.

[0098] Returning to Figure 5, the first setting unit 224 sets a detection area 30 corresponding to the crosswalk 20 in the sensor coordinate system (X, Y, Z) based on the coordinate values ​​(first sensor coordinate values) of first specific points P1, P2, P3, and P4 in the sensor coordinate system (X, Y, Z).

[0099] Specifically, the first setting unit 224 determines the coordinate values ​​of the vertices of the detection area 30 in the sensor coordinate system (X, Y, Z) based on the coordinate values ​​of the first specific points P1, P2, P3, and P4 in the sensor coordinate system (X, Y, Z). As described above, the detection area 30 is an area extending from the crosswalk 20 to both sides in the longitudinal direction of the crosswalk. For example, the first setting unit 224 extends the rectangle of the crosswalk 20 specified by the first specific points P1, P2, P3, and P4 in the longitudinal direction by a predetermined ratio. For example, the longitudinal direction may be the average of the direction connecting P1 and P2 and the direction connecting P3 and P4, or may be the Y-axis direction in the sensor coordinate system (X, Y, Z).

[0100] The first setting unit 224 sets the detection area 30 corresponding to the crosswalk 20 in the sensor coordinate system based on the coordinate values ​​of each vertex of the detection area 30 in the sensor coordinate system (X, Y, Z). In a specific example, after determining the coordinate values ​​of each vertex of the detection area 30 in the sensor coordinate system (X, Y, Z), the first setting unit 224 generates setting information 111 including the determined coordinate values ​​and stores the generated setting information 111 in the non-volatile memory 202. The first setting unit 224 transmits the generated setting information 111 to the infrastructure radio wave sensor 10 and stores the setting information 111 in the non-volatile memory 102 of the infrastructure radio wave sensor 10. In this way, the detection area 30 is set in the infrastructure radio wave sensor 10.

[0101] The display control unit 225 displays the detection area 30 set by the first setting unit 224 and the radio wave irradiation area 40 of the infrastructure radio wave sensor 10 in a superimposed manner on the display device 212. Specifically, for example, position information of the radio wave irradiation area 40 in the sensor coordinate system (X, Y, Z) is stored in the non-volatile memory 202. The display control unit 225 can display the radio wave irradiation area 40 on the display device 212 using the position information of the radio wave irradiation area 40 in the sensor coordinate system (X, Y, Z).

[0102] 9A is a diagram showing a first example of the display of the set detection area. For example, the display control unit 225 displays a first image 301 (or a second image 302) on the display device 212, and superimposes a virtual frame 30A that virtually represents the detection area 30 and a virtual frame 40A that virtually represents the radio wave irradiation area 40 on the first image 301. This allows the user to easily confirm the positional relationship between the detection area 30 and the crosswalk 20, and the positional relationship between the detection area 30 and the radio wave irradiation area 40.

[0103] 9A shows an example in which the detection area 30 is included within the radio wave irradiation area 40, i.e., the entire virtual frame 30A is included within the virtual frame 40A. In this case, the infrastructure radio wave sensor 10 can detect objects in the entire detection area 30.

[0104] 9B is a diagram showing a second example of a display of the set detection area. Fig. 9B shows an example in which the entire detection area 30 is not included within the radio wave irradiation area 40, and part of the detection area 30 is outside the radio wave irradiation area 40. That is, in Fig. 9B, part of the imaginary frame 30A is outside the imaginary frame 40A. In this case, the infrastructure radio wave sensor 10 cannot detect an object in part of the detection area 30 (the part outside the radio wave irradiation area 40).

[0105] 5 , the first determination unit 226 determines whether or not the detection area 30 set by the first setting unit 224 is included in the radio wave irradiation area 40 of the infrastructure radio wave sensor 10. Specifically, the first determination unit 226 determines whether or not the detection area 30 is included in the radio wave irradiation area 40 based on the setting information 111 stored in the non-volatile memory 202 by the first setting unit 224 and the position information of the radio wave irradiation area 40 described above.

[0106] If the first determination unit 226 determines that the detection area 30 is included in the radio wave irradiation area 40, the infrastructure radio wave sensor 10 can detect objects in the entire detection area 30. Therefore, the detection area 30 has been set correctly, and there is no need to reset the detection area 30. On the other hand, if the first determination unit 226 determines that a part of the detection area 30 falls outside the radio wave irradiation area 40, the infrastructure radio wave sensor 10 cannot detect objects in that part of the detection area 30. Therefore, the detection area 30 has been set incorrectly, and the detection area 30 needs to be reset.

[0107] If the first determination unit 226 determines that part of the detection area 30 falls outside the radio wave irradiation area 40, the user adjusts the installation angle of the infrastructure radio wave sensor 10 so that the entire detection area 30 is included in the radio wave irradiation area 40. As a result, the crosswalk 20 may no longer fit within the field of view of the first image sensor 131 and the second image sensor 132. In this case, the user adjusts the angles of the first imaging device 131A and the second imaging device 132A relative to the housing 140 so that the crosswalk 20 fits within the field of view of the first image sensor 131 and the second image sensor 132.

[0108] When the relative angles between the first image sensor 131 and the second image sensor 132 and the infrastructure radio wave sensor 10 (the transmitting antenna 105a and the receiving antenna 106a) change, the relative positional relationship between the intermediate coordinate system and the sensor coordinate system no longer corresponds to the relative positional relationship between the first image sensor 131 and the second image sensor 132 and the infrastructure radio wave sensor 10. For this reason, it is necessary to change the transformation parameters that indicate the relative positional relationship between the intermediate coordinate system and the sensor coordinate system according to the angle adjustment amount of the first mounting portion 141 and the second mounting portion 142.

[0109] The parameter change unit 227 changes a transformation parameter indicating the relative positional relationship between the intermediate coordinate system and the sensor coordinate system in accordance with the angle adjustment amount of the first mounting portion 141 and the second mounting portion 142. For example, the parameter change unit 227 changes the transformation parameter using the angle adjustment amount detected by the angle sensor 141A. By changing the transformation parameter, the parameter change unit 227 causes the relative positional relationship between the intermediate coordinate system and the sensor coordinate system to correspond to the relative positional relationship between the first image sensor 131, the second image sensor 132, and the infrastructure radio wave sensor 10.

[0110] When the transformation parameters are changed by the parameter change unit 227, the acquisition unit 221 acquires the first image 301 and the second image 302 after the angles of the first attachment portion 141 and the second attachment portion 142 have been adjusted. The newly acquired first image 301 and second image 302 are used to set the detection area 30 as described above.

[0111] If the first determination unit 226 determines that the detection area 30 is included in the radio wave irradiation area 40, the second determination unit 228 determines whether or not a detection failure will occur in the detection area 30 by the infrastructure radio wave sensor 10. That is, if the first determination unit 226 determines that the detection area 30 is included in the radio wave irradiation area 40, setting information 111 for the detection area 30 is transmitted to the infrastructure radio wave sensor 10, and the setting information 111 is stored in the non-volatile memory 102 of the infrastructure radio wave sensor 10. As a result, the detection area 30 created by the setting device 200 is reflected in the infrastructure radio wave sensor 10. The infrastructure radio wave sensor 10 performs object detection using the newly set detection area 30. The infrastructure radio wave sensor 10 transmits detection data to the setting device 200. The second determination unit 228 determines whether or not a detection failure will occur using the detection data transmitted from the infrastructure radio wave sensor 10.

[0112] For example, the second determination unit 228 may use the result of a worker walking in a specific pattern at a specific position on the crosswalk 20 and the infrastructure radio wave sensor 10 detecting the walking worker as a result of the worker being detected. For example, the worker walks counterclockwise around the perimeter of the crosswalk 20, and the infrastructure radio wave sensor 10 detects the worker. The second determination unit 228 determines that a detection failure has not occurred if it is able to detect an object moving throughout the entire perimeter of the detection area 30 set in the sensor coordinate system. The second determination unit 228 determines that a detection failure has occurred if it is unable to detect an object (worker) in at least a portion of the perimeter of the detection area 30.

[0113] Even if the entire detection area 30 is included in the radio wave irradiation area 40, if a detection failure occurs, it is considered that there is an area where the infrastructure radio wave sensor 10 is not able to properly receive reflected waves. Therefore, if a detection failure occurs, the infrastructure radio wave sensor 10 is not able to detect an object in part of the detection area 30. Therefore, the detection area 30 is not set correctly, and it is necessary to reset the detection area 30.

[0114] If the second determination unit 228 determines that a detection failure has occurred, the user adjusts the installation angle of the infrastructure radio wave sensor 10. As a result, the crosswalk 20 may no longer fit within the fields of view of the first image sensor 131 and the second image sensor 132. In this case, the user adjusts the angles of the first imaging device 131A and the second imaging device 132A relative to the housing 140 so that the crosswalk 20 fits within the fields of view of the first image sensor 131 and the second image sensor 132. In this case, the parameter change unit 227 changes the transformation parameter that indicates the relative positional relationship between the intermediate coordinate system and the sensor coordinate system, depending on the angle adjustment amount of the first mounting unit 141 and the second mounting unit 142.

[0115] Objects that are constantly detected by the infrastructure radio wave sensor 10, such as stationary objects such as traffic light poles and frequently detected objects such as shrubs, can cause false detection of passersby. For this reason, an exclusion area is set in the infrastructure radio wave sensor 10 to prevent false detection of stationary objects such as buildings and structures near the detection area and frequently detected objects such as trees as the object to be detected.

[0116] The second determination unit 229 determines second specific points in each of the first image 301 and the second image 302 that identify non-target areas that include objects to be excluded from detection targets.

[0117] For example, the non-target area may be a rectangular area. The second specific points are four vertices of the quadrangular non-target area. However, the number of second specific points is not limited to four. For example, if the non-target area is a polygon having m vertices (an m-gon), the second specific points are each of the m vertices.

[0118] FIG. 10 is a diagram showing an example of a second specific point. In FIG. 10, the non-target area is a rectangle. Therefore, the second specific points are the four vertices of the non-target area. In the example of FIG. 10, the objects to be excluded from detection are a tree, a pedestrian traffic light (hereinafter referred to as a "first traffic light") installed on the sidewalk opposite the sidewalk on which the infrastructure radio wave sensor 10 is installed across the crosswalk 20 (hereinafter referred to as a "first traffic light"), and a pedestrian traffic light (hereinafter referred to as a "second traffic light") installed on the sidewalk on which the infrastructure radio wave sensor 10 is installed.

[0119] 10 , a first image 301 includes an image 21_1 of a tree, and a second image 302 includes an image 21_2 of a tree. The first image 301 includes an image 22_1 of a first traffic light, and a second image 302 includes an image 22_2 of the first traffic light. The first image 301 includes an image 23_1 of a second traffic light, and a second image 302 includes an image 23_2 of the second traffic light.

[0120] In the first image 301, a non-target area 401_1 including a tree image 21_1 is defined, a non-target area 402_1 including a first traffic light image 22_1 is defined, and a non-target area 403_1 including a second traffic light image 23_1 is defined. In the second image 302, a non-target area 401_2 including a tree is defined, a non-target area 402_2 including a first traffic light is defined, and a non-target area 403_2 including a second traffic light is defined.

[0121] In the first image 301, the second specific points corresponding to the trees are vertices p31, p32, p33, and p34 of the non-target area 401_1. Therefore, the coordinate values ​​of the second specific points of the non-target area 401_1 in the first image coordinate system (x_R, y_R) (hereinafter also referred to as "third image coordinate values") are p31 (x31_R, y31_R), p32 (x32_R, y32_R), p33 (x33_R, y33_R), and p34 (x34_R, y34_R).

[0122] In the second image 302, the second specific points corresponding to the trees are vertices p41, p42, p43, and p44 of the non-target area 401_2. Therefore, the coordinate values ​​of the second specific points of the non-target area 401_2 in the second image coordinate system (x_L, y_L) (hereinafter also referred to as "fourth image coordinate values") are p41 (x41_L, y41_L), p42 (x42_L, y42_L), p43 (x43_L, y43_L), and p44 (x44_L, y44_L).

[0123] In the first image 301, the second specific points corresponding to the second traffic light are vertices p71, p72, p73, and p74 of the non-target area 403_1. Therefore, the third image coordinate values ​​of the second specific points of the non-target area 403_1 in the first image coordinate system (x_R, y_R) are p71 (x71_R, y71_R), p72 (x72_R, y72_R), p73 (x73_R, y73_R), and p74 (x74_R, y74_R).

[0124] In the second image 302, the second specific points corresponding to the second traffic light are vertices p81, p82, p83, and p84 of the non-target area 403_2. Therefore, the fourth image coordinate values ​​of the second specific points of the non-target area 403_2 in the second image coordinate system (x_L, y_L) are p81 (x81_L, y81_L), p82 (x82_L, y82_L), p83 (x83_L, y83_L), and p84 (x84_L, y84_L).

[0125] The following describes the setting of the exclusion areas by the non-target areas 401_1 and 401_2 of trees as a representative example. The setting of the exclusion areas by the non-target areas 402_1 and 402_2 of the first traffic light and the non-target areas 403_1 and 403_2 of the second traffic light is similar.

[0126] The second determination unit 229 determines third image coordinate values ​​p31 (x31_R, y31_R), p32 (x32_R, y32_R), p33 (x33_R, y33_R), and p34 (x34_R, y34_R) of the second specific point in such a first image 301, and determines fourth image coordinate values ​​p41 (x41_L, y41_L), p42 (x42_L, y42_L), p43 (x43_L, y43_L), and p44 (x44_L, y44_L) of the second specific point in the second image coordinate system (x_L, y_L).

[0127] In a specific example, the second determination unit 229 determines the third image coordinate values ​​by accepting a user specification of the third image coordinate values ​​in the first image 301. For example, the user specifies the third image coordinate values ​​p31 (x31_R, y31_R), p32 (x32_R, y32_R), p33 (x33_R, y33_R), and p34 (x34_R, y34_R) of the second specific point by touching the four corners of a rectangle surrounding the tree image 21_1 in the first image 301 displayed on the display device 212. The second determination unit 229 accepts the specification of the coordinate values ​​from the user and determines the specified coordinate values ​​as the third image coordinate values ​​of the second specific point.

[0128] In a more specific example, the second determination unit 229 determines the fourth image coordinate values ​​by accepting a user specification of the fourth image coordinate values ​​in the second image 302. For example, the user specifies the fourth image coordinate values ​​p41 (x41_L, y41_L), p42 (x42_L, y42_L), p43 (x43_L, y43_L), and p44 (x44_L, y44_L) of the second specific point by touching the four corners of a rectangle surrounding the tree image 21_2 in the displayed second image 302. The second determination unit 229 accepts the specification of the coordinate values ​​from the user and determines the specified coordinate values ​​as the fourth image coordinate values ​​of the second specific point.

[0129] A pattern for specifying the third image coordinate values ​​of the second specific points in the first image 301 and the fourth image coordinate values ​​of the second specific points in the second image 302 may be determined in advance. For example, a pattern may be determined in which four second specific points in the first image 301 are specified in clockwise order from the top left second specific point, and four second specific points in the second image 302 are specified in clockwise order from the top left second specific point. In a more specific example, a pattern may be determined in which the second specific points in the first image 301 and the second specific points in the second image 302 are specified alternately. That is, the user designates the second specific point p31 at the upper left in the first image 301, the second specific point p41 at the upper left in the second image 302, the second specific point p32 at the upper right in the first image 301, the second specific point p42 at the upper right in the second image 302, the second specific point p33 at the lower right in the first image 301, the second specific point p43 at the lower right in the second image 302, the second specific point p34 at the lower left in the first image 301, and the second specific point p44 at the lower left in the second image 302. This allows the second determination unit 229 to easily recognize corresponding points in the images 21_1 and 22_2.

[0130] However, the method for determining the third image coordinate value of the second specific point in first image 301 and the fourth image coordinate value of the second specific point in second image 302 is not limited to the above. For example, the second determination unit 229 may determine, by image processing on second image 302, coordinate values ​​in the second image coordinate system that correspond to the determined third image coordinate values, and determine the determined coordinate values ​​in the second image coordinate system as the fourth image coordinate values. The method for determining coordinate values ​​by image processing in the second determination unit 229 is similar to the method for determining coordinate values ​​by image processing in the first determination unit 222, and therefore description thereof will be omitted.

[0131] As yet another example, the second determination unit 229 may perform image processing (e.g., image recognition processing using a trained model) on each of the first image 301 and the second image 302 to recognize a second specific point in the first image 301 and a second specific point in the second image 302. In a specific example, trees, traffic signals, and the like are predefined in the setting device 200 as objects to be excluded from detection targets. The second determination unit 229 recognizes objects to be excluded from detection targets in each of the first image 301 and the second image 302. The second determination unit 229 determines the vertices of a rectangle that encloses the image of the object recognized in the first image 301 as the second specific points, and determines the vertices of the rectangle that encloses the image of the recognized object as the second specific points. This allows the second determination unit 229 to determine a third image coordinate value of the second specific point in the first image 301 and a fourth image coordinate value of the second specific point in the second image 302 without user designation.

[0132] Returning to Figure 5, the second conversion unit 230 converts the third image coordinate values, which are the coordinate values ​​of the second specific point in the first image coordinate system of the first image 301, and the fourth image coordinate values, which are the coordinate values ​​of the second specific point in the second image coordinate system of the second image 302, into second sensor coordinate values, which are the coordinate values ​​of the second specific point in the sensor coordinate system set in the infrastructure radio wave sensor 10.

[0133] In a specific example, the second conversion unit 230 converts the third image coordinate value and the fourth image coordinate value into coordinate values ​​of a second specific point in the intermediate coordinate system.

[0134] That is, the second conversion unit 230 converts, by stereo matching, the third image coordinate value of the second specific point in the first image 301 and the fourth image coordinate value of the second specific point in the second image 302 into the coordinate value of the second specific point in the intermediate coordinate system. The coordinate conversion by the second conversion unit 230 using the stereo matching method is similar to the coordinate conversion by the first conversion unit 223 using the stereo matching method, and therefore a description thereof will be omitted.

[0135] Furthermore, the second conversion unit 230 converts the coordinate values ​​of the second specific point in the intermediate coordinate system into coordinate values ​​of the second specific point in the sensor coordinate system (second sensor coordinate values). The coordinate conversion from the intermediate coordinate system to the sensor coordinate system by the second conversion unit 230 is similar to the coordinate conversion from the intermediate coordinate system to the sensor coordinate system by the first conversion unit 223, and therefore a description thereof will be omitted. Note that the coordinate conversion by the second conversion unit 230 uses the conversion parameters used in the coordinate conversion by the first conversion unit 223.

[0136] The second setting unit 231 sets an exclusion area corresponding to the non-target area in the sensor coordinate system based on the coordinate values ​​of the second specific point in the sensor coordinate system (second sensor coordinate values).

[0137] Specifically, the second setting unit 231 sets the exclusion area by taking the coordinate values ​​of each second specific point in the sensor coordinate system as the coordinate values ​​of the vertices of the exclusion area. For example, the coordinate values ​​of each second specific point in the non-target area corresponding to a tree are set as the coordinate values ​​of the exclusion area. Therefore, in the sensor coordinate system, a rectangular area including the tree becomes the exclusion area. Similarly, the second setting unit 231 takes the coordinate values ​​of each second specific point in the non-target area corresponding to the first traffic light as the coordinate values ​​of the exclusion area. As a result, in the sensor coordinate system, a rectangular area including the first traffic light becomes the exclusion area. The second setting unit 231 takes the coordinate values ​​of each second specific point in the non-target area corresponding to the second traffic light as the coordinate values ​​of the exclusion area. As a result, in the sensor coordinate system, a rectangular area including the second traffic light becomes the exclusion area.

[0138] The second setting unit 231 sets an exclusion area in the sensor coordinate system that corresponds to the non-target area, based on the coordinate values ​​of each vertex of the exclusion area in the sensor coordinate system. In a specific example, after determining the coordinate values ​​of each vertex of the exclusion area in the sensor coordinate system, the second setting unit 231 generates setting information 111 including the determined coordinate values ​​and stores the generated setting information 111 in the non-volatile memory 202. The second setting unit 231 transmits the generated setting information 111 to the infrastructure radio wave sensor 10, and stores the setting information 111 in the non-volatile memory 102 of the infrastructure radio wave sensor 10. In this way, the exclusion area is set in the infrastructure radio wave sensor 10.

[0139] 6. Setting Operation of Setting Device The operation of the setting device 200 for setting a detection area for the infrastructure radio wave sensor 10 will be described below.

[0140] FIG. 11 is a flowchart illustrating an example of the operation of the setting device according to the embodiment.

[0141] The worker attaches the infrastructure radio wave sensor 10 to the structure 50 and points the infrastructure radio wave sensor 10 toward the crosswalk 20. The worker attaches the first imaging device 131A to the first mounting portion 141 of the infrastructure radio wave sensor 10 and attaches the second imaging device 132A to the second mounting portion 142. At this time, the worker adjusts the angles of the first mounting portion 141 and the second mounting portion 142 so that the crosswalk 20 is included in the field of view of the first image sensor 131 and the field of view of the second image sensor 132.

[0142] The first image sensor 131 and the second image sensor 132 synchronously output a first image 301 and a second image 302, respectively, to the detection circuit 120 of the infrastructure radio wave sensor 10. The detection circuit 120 transmits the first image 301 and the second image 302, respectively, to the setting device 200.

[0143] The setting device 200 receives the first image 301 and the second image 302, and the processor 201 acquires the first image 301 and the second image 302 (step S101).

[0144] The processor 201 determines first specific points that identify the crosswalk 20 in each of the acquired first image 301 and second image 302 (step S102). Specifically, the processor 201 determines the four corners of the images 20_1 and 20_2 of the crosswalk 20 in each of the first image 301 and the second image 302 as the first specific points. The first specific points may be determined by the user specifying the first specific points on the images, or may be determined by image recognition processing.

[0145] The processor 201 executes coordinate transformation processing to transform the coordinate values ​​of the first specific point in the first image coordinate system of the first image 301 (first image coordinate values) and the coordinate values ​​of the first specific point in the second image coordinate system of the second image 302 (second image coordinate values) into coordinate values ​​of the first specific point in the sensor coordinate system (first sensor coordinate values). Specifically, the processor 201 first transforms the first image coordinate values ​​and the second image coordinate values ​​into coordinate values ​​of the first specific point in the intermediate coordinate system (intermediate coordinate values) by a stereo matching method. Next, the processor 201 transforms the intermediate coordinate values ​​of the first specific point in the intermediate coordinate system into coordinate values ​​of the first specific point in the sensor coordinate system (first sensor coordinate values).

[0146] Next, the processor 201 sets a detection area 30 corresponding to the crosswalk 20 in the sensor coordinate system based on the first sensor coordinate value of the first specific point in the sensor coordinate system (step S104). Specifically, the processor 201 extends the rectangle of the crosswalk 20 specified by the first specific point in the longitudinal direction by a predetermined ratio to determine the detection area in the sensor coordinate system. The processor 201 generates setting information 111 including the coordinate values ​​of the determined detection area and stores the generated setting information 111 in the non-volatile memory 202. The processor 201 then transmits the generated setting information 111 to the infrastructure radio wave sensor 10, causing the non-volatile memory 102 of the infrastructure radio wave sensor 10 to store the setting information 111.

[0147] The processor 201 causes the display device 212 to display the set detection area 30 (a virtual frame 30A indicating the detection area 30) and the radio wave irradiation area 40 (a virtual frame 40A indicating the detection area 30) in a superimposed manner (step S105).

[0148] The processor 201 determines whether the set detection area 30 is included in the radio wave irradiation area 40 (step S106).

[0149] If at least a part of the detection area 30 is outside the radio wave irradiation area 40 (NO in step S106), for example, the processor 101 causes the display device 212 to display information indicating that the setting of the detection area 30 is inappropriate (abnormal). This notifies the user that at least a part of the detection area 30 is outside the radio wave irradiation area 40. Note that the user can also understand that at least a part of the detection area 30 is outside the radio wave irradiation area 40 by checking the positional relationship between the detection area 20 and the radio wave irradiation area 40 superimposed and displayed on the display device 212.

[0150] The user adjusts the installation angle of the infrastructure radio wave sensor 10 so that the crosswalk 20 is included in the radio wave irradiation area 40. Furthermore, the user adjusts the angles of the first imaging device 131A and the second imaging device 132A relative to the housing 140 so that the crosswalk 20 is included in the field of view of the first image sensor 131 and the second image sensor 132.

[0151] The angle sensor 141A detects the angle adjustment amount of the first attachment portion 141 (and the second attachment portion 142). The angle sensor 141A outputs the detection result of the angle adjustment amount to the detection circuit 120 of the infrastructure radio wave sensor 10. The detection circuit 120 transmits the angle adjustment amount to the setting device 200.

[0152] The setting device 200 receives the angle adjustment amount detected by the angle sensor 141A, and the processor 201 acquires the angle adjustment amount (step S107). The processor 201 changes the transformation parameters indicating the relative positional relationship between the intermediate coordinate system and the sensor coordinate system according to the angle adjustment amount of the first mounting portion 141 (and the second mounting portion 142) (step S108). After step S108, the processor 201 returns to step S101.

[0153] If the entire detection area 30 is included in the radio wave irradiation area 40 (YES in step S106), detection data is output from the infrastructure radio wave sensor 10 to the setting device 200, and the processor 201 acquires the detection data (step S109). At this time, for example, the worker walks around the perimeter of the crosswalk 20. As a result, detection data indicating the result of object detection by the infrastructure radio wave sensor 10 while the worker is walking around the perimeter of the crosswalk 20 is provided to the processor 201.

[0154] The processor 201 determines, based on the detection data, whether a detection failure will occur in the detection area 30 by the infrastructure radio wave sensor 10 (step S110). If it is determined that a detection failure will occur (YES in step S110), the processor 201 displays information indicating that the setting of the detection area 30 is inappropriate (abnormal) on the display device 212. This notifies the user that a detection failure has occurred. In this case, the processor 201 proceeds to step S107.

[0155] When it is determined that no detection failure has occurred (NO in step S110), the processor 201 determines second specific points that specify non-target areas including objects to be excluded from detection targets in each of the first image 301 and the second image 302 (step S111). Specifically, the processor 201 determines the four corners of a rectangle that surrounds an object to be excluded from detection targets, such as a tree or a traffic signal, in each of the first image 301 and the second image 302 as the second specific points. The second specific points may be determined by a user specifying the second specific points on the images, or may be determined by image recognition processing.

[0156] The processor 201 executes coordinate transformation processing to transform the coordinate values ​​of the second specific point in the first image coordinate system of the first image 301 (third image coordinate values) and the coordinate values ​​of the second specific point in the second image coordinate system of the second image 302 (fourth image coordinate values) into coordinate values ​​of the second specific point in the sensor coordinate system (second sensor coordinate values). Specifically, the processor 201 first transforms the third image coordinate values ​​and the fourth image coordinate values ​​into coordinate values ​​of the second specific point in the intermediate coordinate system by a stereo matching method. Next, the processor 201 transforms the coordinate values ​​of the second specific point in the intermediate coordinate system into coordinate values ​​of the second specific point in the sensor coordinate system (second sensor coordinate values).

[0157] Next, the processor 201 sets an exclusion area in the sensor coordinate system corresponding to the non-target area based on the second sensor coordinate values ​​of the second specific point in the sensor coordinate system (step S113). The processor 201 generates setting information 111 including the coordinate values ​​of the exclusion area and stores the generated setting information 111 in the non-volatile memory 202. The processor 201 then transmits the generated setting information 111 to the infrastructure radio wave sensor 10, causing the non-volatile memory 102 of the infrastructure radio wave sensor 10 to store the setting information 111. This completes the setting of the detection area 30 in the infrastructure radio wave sensor 10.

[0158] 7. Variations In the above-described embodiment, a two-stage coordinate transformation process has been described in which the stereo matching method is used to transform the coordinate values ​​of the first specific point in the first image coordinate system of the first image 301 (first image coordinate values) and the coordinate values ​​of the first specific point in the second image coordinate system of the second image 302 (second image coordinate values) into coordinate values ​​of the first specific point in an intermediate coordinate system (intermediate coordinate values), and then the intermediate coordinate values ​​of the first specific point in the intermediate coordinate system are transformed into coordinate values ​​of the first specific point in the sensor coordinate system (first sensor coordinate values). However, this is not limiting. Direct transformation from the first image coordinate values ​​and the second image coordinate values ​​to the first sensor coordinate values ​​is also possible. The same applies to the coordinate transformation process of the second specific point that identifies the non-target area.

[0159] In the above-described embodiment, a method for setting the detection area 30 for the infrastructure radio wave sensor 10 that detects pedestrians on the crosswalk 20 has been described, but the present disclosure is not limited to this. For example, the method disclosed herein can also be used to set the detection area for an infrastructure radio wave sensor that detects vehicles traveling on a roadway.

[0160] [8. Supplementary Note] The embodiments disclosed herein are illustrative in all respects and are not restrictive. The scope of the present disclosure is defined by the claims, not the above-described embodiments, and includes meanings equivalent to the claims and all modifications within the scope thereof.

[0161] 10 Infrastructure radio wave sensor 20 Crosswalk (target area) 30 Detection area 40 Radio wave irradiation area 50 Structure 51 Pole 52 Arm 101 Processor 102 Non-volatile memory 103 Volatile memory 104 Transmitter / receiver 105 Transmission circuit 105a Transmission antenna 106 Receiving circuit 106a Receiving antenna (antenna) 107 Communication interface 108 Input / output interface 110 Control program 111 Setting information 120 Detection circuit 131 First image sensor 131A First imaging device 132 Second image sensor 132A Second imaging device 140 Housing 140a Transmission / reception surface 141 First mounting portion 141A Angle sensor 142 Second mounting portion 200 Setting device 201 Processor 202 Non-volatile memory 203 Volatile memory 204 Input / output interface 205 Graphic controller 206 Communication interface 210 Setting program 211 Input device 212 Display device 221 Acquisition unit 222 First determination unit 223 First conversion unit 224 First setting unit 225 Display control unit 226 First judgment unit 227 Parameter change unit 228 Second judgment unit 229 Second determination unit 230 Second conversion unit 231 Second setting unit 301 First image 302 Second image 20_1, 20_2 Crosswalk images p11, p21, p12, p22, p13, p23, p14, p24, p1, p2, p3, p4, P1, P2, P3, P4 First specific points 30A, 40A Virtual frames 21_1, 21_2 Tree images 22_1, 22_2 Traffic light image 23_1, 23_2 Traffic light image 401_1, 402_1, 403_1, 401_2, 402_2, 403_2 Non-target area p31, p32, p33, p34, p41, p42, p43, p44, p51, p52, p53, p54, p61, p62, p63, p64, p71, p72, p73, p74, p81, p82, p83, p84 Second specific point

Claims

1. The steps include acquiring a first image and a second image from the first image sensor and the second image sensor, respectively, which include the target area for object detection on the road by the radio wave sensor, The steps include determining a first specific point for identifying the target area in each of the acquired first and second images, The steps include converting the first image coordinate values, which are the coordinate values ​​of the first specific point in the first image coordinate system, which is the coordinate system of the first image, and the second image coordinate values, which are the coordinate values ​​of the first specific point in the second image coordinate system, which is the coordinate system of the second image, into first sensor coordinate values, which are the coordinate values ​​of the first specific point in the sensor coordinate system, which is the coordinate system set for the radio wave sensor, A step of setting a detection area corresponding to the target area in the sensor coordinate system based on the coordinate values ​​of the first sensor, including, How to set up the radio wave sensor.

2. In the step of determining the above, the first image coordinate values ​​are determined by receiving a specification from the user for the first image coordinate values ​​in the first image. A method for setting up a radio wave sensor according to claim 1.

3. In the step of determining the above, the second image coordinate values ​​are determined by receiving a user's specification of the second image coordinate values ​​in the second image. The method for setting up the radio wave sensor according to claim 2.

4. In the step of determining, the coordinate values ​​in the second image coordinate system corresponding to the determined first image coordinate values ​​are identified by image processing of the second image, and the identified coordinate values ​​in the second image coordinate system are determined as the second image coordinate values. The method for setting up the radio wave sensor according to claim 2.

5. In the step of determining the above, the first image coordinate values ​​are determined by recognizing the first specific point in the first image by image processing, and the second image coordinate values ​​are determined by recognizing the first specific point in the second image by image processing. A method for setting up a radio wave sensor according to claim 1.

6. The aforementioned conversion step is: The steps include converting the first image coordinate values ​​and the second image coordinate values ​​into intermediate coordinate values ​​which are the coordinate values ​​of the first specific point in an intermediate coordinate system that is a three-dimensional coordinate system composed of the first image and the second image, The steps include converting the intermediate coordinate values ​​to the first sensor coordinate values, including, A method for setting up a radio wave sensor according to claim 1.

7. The step further includes determining whether the detection area set based on the first sensor coordinate values ​​is included in the radio wave irradiation area of ​​the radio wave sensor, A method for setting up a radio wave sensor according to claim 1.

8. The step further includes displaying the detection area set based on the coordinate values ​​of the first sensor and the radio wave irradiation area of ​​the radio wave sensor superimposed on each other. A method for setting up a radio wave sensor according to claim 1.

9. The steps include determining a second specific point in each of the first and second images that identifies a non-target area containing an object to be excluded from detection, The steps include converting the third image coordinate value, which is the coordinate value of the second specific point in the first image coordinate system, and the fourth image coordinate value, which is the coordinate value of the second specific point in the second image coordinate system, into the second sensor coordinate value, which is the coordinate value of the second specific point in the sensor coordinate system. A step of setting an exclusion area corresponding to the non-target area in the sensor coordinate system based on the second sensor coordinate values, Further including, A method for setting up a radio wave sensor according to claim 1.

10. The method further includes the step of adjusting the angle of at least one of the first image sensor and the second image sensor with respect to the antenna for transmitting and receiving radio waves included in the radio wave sensor, In the step of acquiring the first image and the second image, after the angle of at least one of the first image sensor and the second image sensor has been adjusted, the first image and the second image are acquired from the output of the first image sensor and the second image sensor, respectively. A method for setting a radio wave sensor according to any one of claims 1 to 9.

11. The method further includes the step of changing the conversion parameters used to convert the first image coordinate values ​​and the second image coordinate values ​​to the first sensor coordinate values, in accordance with the amount of angle adjustment of the first image sensor and the second image sensor with respect to the antenna. A method for setting up a radio wave sensor according to claim 10.

12. An acquisition unit acquires a first image and a second image from the first image sensor and the second image sensor, respectively, which include the target area for object detection on the road by the radio wave sensor. A determination unit determines a first specific point for identifying the target area in each of the first and second images acquired by the acquisition unit, A conversion unit converts the first image coordinate values, which are the coordinate values ​​of the first specific point in the first image coordinate system, which is the coordinate system of the first image, and the second image coordinate values, which are the coordinate values ​​of the first specific point in the second image coordinate system, which is the coordinate system of the second image, into first sensor coordinate values, which are the coordinate values ​​of the first specific point in the sensor coordinate system, which is the coordinate system set for the radio wave sensor. A setting unit sets a detection area corresponding to the target area in the sensor coordinate system based on the first sensor coordinate values, Equipped with, A setting device for radio wave sensors.

13. An antenna that transmits radio waves to an area on a road and receives reflected waves of the radio waves from an object in the area, A detection circuit that detects the position of the object based on the reflected wave received by the antenna, A housing that houses the antenna and the detection circuit, Mounting portions are provided on the housing for attaching the first image sensor and the second image sensor, respectively. Equipped with, Radio wave sensor.

14. The mounting portion includes an angle adjustment mechanism for adjusting the angle of at least one of the first image sensor and the second image sensor relative to the antenna. The radio wave sensor according to claim 13.