Radio wave sensor setting method, setting device, and computer program

Abstract

This radio wave sensor setting method sets up, for a radio wave sensor, a detection area defined on a road, and comprises: a step for obtaining the coordinate values, in a latitude-longitude coordinate system, of each of a plurality of definition points that define the detection area; a step for converting the coordinate values of each of the plurality of definition points in the latitude-longitude coordinate system to coordinate values in a unique coordinate system used by the radio wave sensor; and a step for setting up the detection area for the radio wave sensor on the basis of the coordinate values of each of the plurality of definition points in the unique coordinate system.

Description

Radio wave sensor setting method, setting device, and computer program

[0001] This disclosure relates to a method, a device, and a computer program for setting a radio wave sensor. This application claims priority to Japanese Application No. 2022-126892 filed on August 9, 2022, and incorporates by reference the entire contents of that Japanese 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 or intersections. Such infrastructure (road facility) radio wave sensors are used, for example, to measure the traffic volume of vehicles traveling on roads and detect pedestrians on crosswalks. To use a radio wave sensor for traffic monitoring, it is necessary to set the detection target area (hereinafter referred to as the "detection area"), such as the roadway, lanes, crosswalks, and sidewalks, in the coordinate system of the radio wave sensor.

[0003] When setting a detection area in a radio wave sensor, a reference object may be used. For example, the detection area is set by placing the reference object at a position that allows identification of the area to be set as the detection area (e.g., a crosswalk), and detecting the reference object with the radio wave sensor. However, there are many objects other than the reference object, such as vehicles and pedestrians, on roads, crosswalks, sidewalks, etc. Therefore, even if an attempt is made to detect reflected waves from the reference object in the radio wave area, it may be difficult to distinguish them from reflected waves (noise) from objects other than the reference object.

[0004] Patent document 1 discloses a method in which a radio wave sensor transmits radio waves to a reference object having a reflecting part while the reference object is being moved, the radio wave sensor receives the waves reflected by the reflecting part, and uses the temporal changes that occur in the detection data obtained from the reflected waves to distinguish between the waves reflected by the reflecting part and noise.

[0005] International Publication No. 2021 / 181981

[0006] A radio wave sensor setting method according to one aspect of the present disclosure is a method for setting a detection area defined on a road on a radio wave sensor, and includes the steps of acquiring coordinate values ​​in a latitude-longitude coordinate system for each of a plurality of definition points that define the detection area, converting the coordinate values ​​in the latitude-longitude coordinate system for each of the plurality of definition points into coordinate values ​​in an intrinsic coordinate system used in the radio wave sensor, and setting the detection area on the radio wave sensor based on the coordinate values ​​in the intrinsic coordinate system for each of the plurality of definition points.

[0007] FIG. 1 is a diagram illustrating an example of use of a radio wave sensor according to an embodiment. FIG. 2 is a block diagram illustrating an example of the hardware configuration of a setting device according to an embodiment. FIG. 3 is a functional block diagram illustrating an example of the functions of the setting device according to an embodiment. FIG. 4 is a diagram illustrating an example of setting a detection area. FIG. 5 is a diagram illustrating an example of correcting a measurement value of a distance to a specific point. FIG. 6 is a diagram illustrating an example of generating a conversion formula. FIG. 7 is a flowchart illustrating an example of a procedure for setting a detection area. FIG. 8 is a flowchart illustrating an example of a conversion formula generation process. FIG. 9 is a flowchart illustrating an example of a detection area setting process.

[0008] <Problem to be Solved by the Present Disclosure> In the method disclosed in Patent Document 1, when the number of detection positions increases in order to set the detection area, it is necessary to move the reference object at each position. Furthermore, it is necessary to acquire redundant detection data including temporal changes for each detection position. For this reason, setting up the radio wave sensor requires a lot of effort and time.

[0009] Effect of the Present Disclosure According to the present disclosure, it is possible to reduce the effort and time required to set up a radio wave sensor.

[0010] <Outline of Embodiments of the Present Disclosure> Below, an outline of embodiments of the present disclosure will be listed and described.

[0011] (1) A radio wave sensor setting method according to this embodiment is a method for setting a detection area defined on a road on a radio wave sensor, and includes the steps of acquiring coordinate values ​​in a latitude-longitude coordinate system for each of a plurality of definition points that define the detection area, converting the coordinate values ​​in the latitude-longitude coordinate system for each of the plurality of definition points into coordinate values ​​in a unique coordinate system used by the radio wave sensor, and setting the detection area on the radio wave sensor based on the coordinate values ​​in the unique coordinate system for each of the plurality of definition points. This allows the detection area to be set on the radio wave sensor by acquiring coordinate values ​​in the latitude-longitude coordinate system that can be acquired without using a radio wave sensor. This reduces the effort and time required to set the radio wave sensor.

[0012] (2) In the above (1), the method for setting the radio wave sensor may further include generating a conversion formula for converting coordinate values ​​of the latitude-longitude coordinate system into coordinate values ​​of the inherent coordinate system based on coordinate values ​​of the latitude-longitude coordinate system and coordinate values ​​of the inherent coordinate system for a plurality of points. By generating a conversion formula for each radio wave sensor, it is possible to correctly set the detection area for the radio wave sensor.

[0013] (3) In the above (2), the plurality of points used to generate the transformation formula may be different from the plurality of defining points, thereby enabling the transformation formula to be generated using points suitable for generating the transformation formula.

[0014] (4) In the above (2) or (3), the plurality of points used to generate the transformation formula may include the origin of the intrinsic coordinate system, thereby making it possible to easily generate the transformation formula.

[0015] (5) In the above (4), the plurality of points used to generate the transformation formula may further include a point on a coordinate axis other than the origin in the intrinsic coordinate system, thereby making it easier to generate the transformation formula.

[0016] (6) In the above (5), the coordinate axes may extend along a reference line that is an intersection line between a vertical plane including the radio wave emission axis of the radio wave sensor and the ground. This allows the point used to generate the conversion formula to be a point in front of the radio wave sensor, making it easy to determine the point.

[0017] (7) In any one of (2) to (6) above, the method for setting the radio wave sensor may further include the steps of acquiring coordinate values ​​in the latitude and longitude coordinate system for the plurality of points used to generate the conversion formula, and detecting, by the radio wave sensor, reference objects placed at each of the plurality of points used to generate the conversion formula, thereby acquiring coordinate values ​​in the intrinsic coordinate system for the plurality of points used to generate the conversion formula. In this way, by detecting the reference objects with the radio wave sensor, it is possible to obtain the coordinate values ​​in the intrinsic coordinate system used to generate the conversion formula.

[0018] (8) In the above (7), in the step of acquiring the coordinate values ​​of the intrinsic coordinate system, the coordinate values ​​of the intrinsic coordinate system of the plurality of points used to generate the conversion formula may be acquired by correcting the measured value of the distance to the reference object by the radio wave sensor based on the height of the radio wave sensor from the ground. This makes it possible to obtain accurate coordinate values ​​of the intrinsic coordinate system used to generate the conversion formula.

[0019] (9) In the above (7) or (8), in the step of acquiring coordinate values ​​in the latitude-longitude coordinate system, the coordinate values ​​in the latitude-longitude coordinate system for the plurality of points used to generate the conversion formula may be acquired before starting the radio wave sensor, thereby reducing the effort required to set up the radio wave sensor.

[0020] (10) A setting device according to this embodiment is a setting device for setting a detection area defined on a road in a radio wave sensor, and includes an input unit that accepts coordinate values ​​in a latitude-longitude coordinate system for each of a plurality of definition points that define the detection area, a conversion unit that converts the coordinate values ​​in the latitude-longitude coordinate system for each of the plurality of definition points into coordinate values ​​in an intrinsic coordinate system used by the radio wave sensor, and a setting unit that sets the detection area in the radio wave sensor based on the coordinate values ​​in the intrinsic coordinate system for each of the plurality of definition points. This allows the detection area to be set in the radio wave sensor by obtaining coordinate values ​​in the latitude-longitude coordinate system that can be obtained without using a radio wave sensor. This reduces the effort and time required to set the radio wave sensor.

[0021] (11) A computer program according to this embodiment is a computer program for setting a detection area defined on a road in a radio wave sensor, and causes a computer to execute the following steps: acquiring coordinate values ​​in a latitude-longitude coordinate system for each of a plurality of definition points that define the detection area; converting the coordinate values ​​in the latitude-longitude coordinate system for each of the plurality of definition points into coordinate values ​​in a unique coordinate system used by the radio wave sensor; and setting the detection area in the radio wave sensor based on the coordinate values ​​in the unique coordinate system for each of the plurality of definition points. This allows the detection area to be set in the radio wave sensor by acquiring coordinate values ​​in the latitude-longitude coordinate system that can be obtained without using a radio wave sensor. This reduces the effort and time required to set the radio wave sensor.

[0022] The present disclosure can be realized not only as a setting method for a radio wave sensor including the characteristic steps described above, but also as a setting device having a characteristic configuration, or as a computer program for causing a computer to execute the characteristic steps. The present disclosure can be realized as a setting system including the setting device, or as a semiconductor integrated circuit in which part or all of the setting device is implemented.

[0023] <Details of the embodiments of the present disclosure> Hereinafter, the details of the 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.

[0024] 1 is a diagram showing an example of use of a radio wave sensor according to an embodiment. The radio wave sensor 10 according to this embodiment is a radio wave radar for traffic monitoring, and detects pedestrians at a crosswalk 20. The radio wave sensor 10 is, for example, a millimeter wave radar.

[0025] The radio wave sensor 10 is attached to a structure 50 provided on a road. The structure 50 is several meters tall, and the 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 radio wave sensor 10 is attached to the arm 52.

[0026] The radio wave sensor 10 detects objects (vehicles, pedestrians, bicycles, etc.) on the road by emitting radio waves (millimeter waves) onto a road, such as a roadway, a lane, a crosswalk, a sidewalk, etc., and receiving the reflected waves. In the example shown in Fig. 1, the radio wave sensor 10 detects pedestrians, bicycles, etc. on a crosswalk 20. More specifically, the radio wave sensor 10 can detect the distance from the radio wave sensor 10 to an object on the crosswalk 20, the speed of the object, and the horizontal angle (azimuth angle) of the position of the object relative to the radio wave emission axis.

[0027] The radio wave sensor 10 sets detection areas 30A, 30B, and 30C, which are ranges on the road for detecting objects. The detection areas 30A, 30B, and 30C are set as part of the radio wave irradiation range 40 of the radio wave sensor 10. In other words, the radio wave irradiation range 40 covers the detection areas 30A, 30B, and 30C. In order for the radio wave sensor 10 to monitor the traffic conditions across the entire crosswalk 20, it is preferable to set detection areas 30A, 30B, and 30C that include the entire crosswalk 20. Note that the radio wave irradiation range 40 is a range in which an object reflects the radio waves irradiated by the radio wave sensor 10 and the 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 radio wave sensor 10 cannot detect an object even if it can irradiate radio waves. However, the radio wave irradiation range 40 is not limited to this and may be the entire range in which the radio wave sensor 10 can irradiate radio waves.

[0028] Detection area 30A is an area that includes crosswalk 20. Detection areas 30B and 30C are areas that include waiting areas where pedestrians wait on the sidewalk for a traffic light before crossing crosswalk 20. Detection area 30B is located closer to radio wave sensor 10 than detection area 30A, and detection area 30C is located farther from radio wave sensor 10 than detection area 30A.

[0029] The detection areas 30A, 30B, and 30C are examples of detection areas, and the detection areas are not limited to these. For example, a detection area may be set on a roadway without a crosswalk, or a detection area may be set for each lane.

[0030] Unless the detection areas 30A, 30B, and 30C are set correctly, the radio wave sensor 10 described above cannot correctly detect pedestrians crossing the crosswalk 20 or pedestrians waiting at a traffic light in the waiting area. Therefore, the detection areas 30A, 30B, and 30C must be correctly set in the radio wave sensor 10. In this embodiment, an operator uses a setting device to set the detection areas 30A, 30B, and 30C in the radio wave sensor 10 described above.

[0031] 2 is a block diagram showing an example of the hardware configuration of a setting device according to this embodiment. The setting device 100 according to this embodiment is used by an operator (user) who sets the detection area of ​​the radio wave sensor 10. The setting device 100 includes a processor 101, a non-volatile memory 102, a volatile memory 103, an input device 104, a display device 105, and a communication interface (communication I / F) 106.

[0032] The volatile memory 103 is, for example, a semiconductor memory such as an SRAM (Static Random Access Memory) or a DRAM (Dynamic Random Access Memory). The non-volatile memory 102 is, for example, a flash memory, a hard disk, or a ROM (Read Only Memory). The non-volatile memory 102 stores a setting program 107, which is a computer program, and data used to execute the setting program 107. Each function of the setting device 100 is realized when the processor 101 executes the setting program 107, which is a computer program stored in the computer's storage device. The setting program 107 can be stored in a recording medium such as a flash memory, a ROM, or a CD-ROM. The processor 101 sets the detection area of ​​the radio wave sensor 10 using the setting program 107.

[0033] 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 be a GPU (Graphics Processing Unit). The processor 101 is, for example, a multi-core processor. The processor 101 may be a single-core processor. The processor 101 may be, for example, an ASIC (Application Specific Integrated Circuit) or a programmable logic device such as a gate array or 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 setting program 107.

[0034] For example, the input device 104 includes a keyboard and a pointing device such as a mouse. The input device 104 may also be a capacitive or pressure-sensitive touchpad overlaid on the screen of the display device 105. The input device 104 is used to input data to the setting device 100.

[0035] The display device 105 includes, for example, a liquid crystal panel or an OEL (organic electroluminescence) panel, and is capable of displaying text or graphic information.

[0036] The communication I / F 106 can communicate with the radio wave sensor 10. The communication I / F 106 is, for example, a wired communication interface and is connected to the radio wave sensor 10 via a signal line. The communication I / F 106 may be a wireless communication interface. The communication I / F 106 can, for example, receive object detection results (position information of the detected object) from the radio wave sensor 10 and transmit setting data of the detection area determined using the setting device 100 to the radio wave sensor 10.

[0037] 3 is a functional block diagram showing an example of the functions of the setting device according to this embodiment. When the processor 101 executes the setting program 107, the setting device 100 functions as an input unit 110, a receiving unit 111, a correcting unit 112, a generating unit 113, a converting unit 114, and a setting unit 115.

[0038] The input unit 110 is mainly realized by the input device 104. The receiving unit 111 is mainly realized by the communication I / F 106. The correcting unit 112, the generating unit 113, the converting unit 114, and the setting unit 115 are mainly realized by the processor 101.

[0039] 4 is a diagram illustrating an example of setting a detection area. Before or after attaching the radio wave sensor 10 to the structure 50, the user determines a plurality of specific points P1 and P2 used to generate a conversion formula for converting coordinate values ​​in a latitude-longitude coordinate system (hereinafter also referred to as "latitude-longitude coordinate values") into coordinate values ​​in the inherent coordinate system of the radio wave sensor 10 (hereinafter also referred to as "intrinsic coordinate values"). The number of specific points is, for example, two.

[0040] The specific points P1 and P2 are points on the ground and are points included in the radio wave irradiation range 40. For example, the specific point P1 is a point vertically below the radio wave sensor 10. For example, the specific point P2 is a point in front of the radio wave sensor 10. More specifically, the specific point P2 is a point on an intersection line (hereinafter referred to as the "reference line") L0 between the ground and a vertical plane including the radio wave irradiation axis of the radio wave sensor 10 (the normal direction of the radio wave irradiation surface of the radio wave sensor 10). However, the specific points P1 and P2 are not limited to these points and may be any two points included in the radio wave irradiation range 40.

[0041] The user measures the latitude and longitude coordinate values ​​of the specific points P1 and P2 using a Global Navigation Satellite System (GNSS) receiver (not shown). The measurement of the latitude and longitude coordinate values ​​of the specific points P1 and P2 is performed, for example, before the radio wave sensor 10 is energized and activated.

[0042] 3, the user inputs the measured latitude and longitude coordinate values ​​of the specific points P1 and P2 into the setting device 100. The input unit 110 receives the latitude and longitude coordinate values ​​of the specific points P1 and P2.

[0043] The intrinsic coordinate system is a coordinate system used in the radio wave sensor 10 and is unique to the radio wave sensor 10. For example, the intrinsic coordinate system is an orthogonal coordinate system with a point vertically below the radio wave sensor 10 as the origin, a reference line L0 as the first coordinate axis (y-axis), and a horizontal axis perpendicular to the reference line L0 as the second coordinate axis (x-axis). In other words, the y-axis of the intrinsic coordinate system in this case extends along the reference line L0. When the specific point P1 is a point vertically below the radio wave sensor 10, the specific point P1 is the origin of the intrinsic coordinate system. When the specific point P2 is a point in front of the radio wave sensor 10, the specific point P2 is a point on the y-axis of the intrinsic coordinate system.

[0044] The user acquires the unique coordinate values ​​of specific points P1 and P2. Specifically, the user places a reference object at specific point P2 and measures the unique coordinate values ​​of the reference object using the radio wave sensor 10. The radio wave sensor 10 detects the reference object and measures the position (distance and azimuth) of the reference object, i.e., the unique coordinate values. The radio wave sensor 10 transmits the measured unique coordinate values ​​of specific point P2. The receiving unit 111 receives the unique coordinate values ​​of specific point P2.

[0045] If the specific point P1 is the origin of the specific coordinate system, there is no need to measure the specific coordinate values ​​of the specific point P1 using the radio wave sensor 10. In this case, the specific coordinate values ​​of the specific point P1 are set in advance. For example, the specific coordinate values ​​of the specific point P1 are pre-stored in the non-volatile memory 102, and the setting device 100 can acquire these by reading the specific coordinate values ​​of the specific point P1 from the non-volatile memory 102. If the specific point P1 is a point other than the origin of the specific coordinate system, the user places a reference object at the specific point P1 and measures the position of the reference object using the radio wave sensor 10 to acquire the specific coordinate values ​​of the specific point P1. In this case, the radio wave sensor 10 transmits the specific coordinate values ​​of the specific point P1, and the receiving unit 111 receives the specific coordinate values ​​of the specific point P1.

[0046] The correction unit 112 obtains the unique coordinate values ​​of the specific points P1 and P2 by correcting the measurement value of the distance to the reference object obtained by the radio wave sensor 10 based on the height of the radio wave sensor 10 from the ground (hereinafter also referred to as the "installation height"). Specifically, the correction unit 112 corrects the unique coordinate value of the specific point P2 based on the installation height of the radio wave sensor 10.

[0047] FIG. 5 is a diagram illustrating an example of correcting the distance measurement value of a specific point. The radio wave sensor 10 detects a reference object 300 placed at a specific point P2 and measures the distance Lg to the reference object 300. For simplicity, it is assumed that the specific point P2 is on the reference line L0, i.e., the y-axis. In this case, the radio wave sensor 10 measures the specific coordinate value of the specific point P2 as (0, Lg). However, the specific coordinate value (0, Lg) of the specific point P2 output from the radio wave sensor 10 includes an error due to the installation height H of the radio wave sensor 10. In other words, the distance yp between the specific points P1 and P2 is different from the distance Lg between the radio wave sensor 10 and the specific point P2.

[0048] The correction unit 112 corrects the inherent coordinate values ​​of the specific point P2 using Pythagoras' theorem. Specifically, in the right triangle formed by the radio wave sensor 10, the specific point P1, and the specific point P2, ２ =yp ２ +H ２ Using this relationship, the correction unit 112 calculates the distance yp from the distance Lg and the installation height H. The correction unit 112 obtains the correct inherent coordinate values ​​(0, yp) of the specific point P2.

[0049] The correction unit 112 does not need to correct the unique coordinate values ​​of the specific point P2. For example, if the specific point P2 is sufficiently far from the radio wave sensor 10, the distance Lg between the radio wave sensor 10 and the specific point P2 will be close to the distance yg between the specific point P1 and the specific point P2, and the error can be ignored. In such a case, the correction unit 112 can be omitted.

[0050] Returning to FIG. 3, the generation unit 113 generates a conversion formula for converting the latitude and longitude coordinate values ​​into the inherent coordinate values ​​based on the latitude and longitude coordinate values ​​and inherent coordinate values ​​of the specific points P1 and P2.

[0051] An example of generating a conversion formula will be described in detail below. Fig. 6 is a diagram for explaining an example of generating a conversion formula. In Fig. 6, coordinate axes Lon and Lat of the latitude-longitude coordinate system are indicated by solid lines, and coordinate axes x and y of the intrinsic coordinate system are indicated by dashed lines. Coordinate axis Lon is the longitude coordinate axis, and coordinate axis Lat is the latitude coordinate axis. θ is the deviation angle of the intrinsic coordinate system with respect to the latitude-longitude coordinate system. The latitude-longitude coordinate value of specific point P1 is (Lon0, Lat0), and the latitude-longitude coordinate value of specific point P2 is (Lon1, Lat1).

[0052] The conversion formula is defined by formula (1). The generator 113 generates a transformation equation by determining the parameters θ, L1, and L2 in equation (1).

[0053] The specific point P2 is set approximately in front of the radio wave sensor 10, but there are cases where the specific point P2 is set off from the reference line L0 due to a deviation in the installation angle of the radio wave sensor 10, a deviation in the setting position of the specific point P2, etc. The generation unit 113 determines the deviation amount DB of the specific point P2 from the reference line L0 from the unique coordinate value of the specific point P2.

[0054] The distance L1 per degree of latitude and the distance L2 per degree of longitude vary depending on the location on the Earth. Therefore, the generation unit 113 calculates L1 and L2 at the installation location of the radio wave sensor 10 from a planar rectangular coordinate system. For example, the generation unit 113 acquires the coordinate values ​​of points (Lon0+1, Lat0) and (Lon0, Lat0+1) in a planar rectangular coordinate system whose origin is the latitude and longitude coordinate value (Lon0, Lat0) of the specific point P1, and calculates L1 and L2. Note that a planar rectangular coordinate system is a coordinate system in which the curved surface of the Earth is projected onto a plane.

[0055] The generation unit 113 calculates the difference (x_diff, y_diff) between the coordinate values ​​of the specific point P1 and the coordinate values ​​of the specific point P2 in the plane rectangular coordinate system. The generation unit 113 determines θ from equation (2).

[0056] This completes the generation of the conversion formula.

[0057] Referring to Figure 4, before or after attaching the radio wave sensor 10 to the structure 50, the user determines definition points P11, P12, P21, P22, P31, P32, P41, and P42 for defining the detection areas 30A, 30B, and 30C, and measures the latitude and longitude coordinate values ​​of the definition points P11, P12, P21, P22, P31, P32, P41, and P42 using a GNSS receiver. When measuring the latitude and longitude coordinate values ​​of the specific points P1 and P2, the user may measure the latitude and longitude coordinate values ​​of the definition points P11, P12, P21, P22, P31, P32, P41, and P42. Alternatively, the user may measure the latitude and longitude coordinate values ​​of the specific points P1 and P2, and then measure the latitude and longitude coordinate values ​​of the definition points P11, P12, P21, P22, P31, P32, P41, and P42, for example, after generating a conversion formula. The measurement of the latitude and longitude coordinate values ​​of the definition points P11, P12, P21, P22, P31, P32, P41, and P42 is performed, for example, before powering on and starting up the radio wave sensor 10. For example, as shown in FIG. 4 , all of the definition points P11, P12, P21, P22, P31, P32, P41, and P42 may be different from the specific points P1 and P2. For example, two of the definition points P11, P12, P21, P22, P31, P32, P41, and P42 may be set as the specific points P1 and P2.

[0058] 3, the user inputs the latitude and longitude coordinate values ​​of the measured definition points P11, P12, P21, P22, P31, P32, P41, and P42 into the setting device 100. The input unit 110 receives the latitude and longitude coordinate values ​​of the definition points P11, P12, P21, P22, P31, P32, P41, and P42.

[0059] The conversion unit 114 converts the latitude and longitude coordinate values ​​of each of the definition points P11, P12, P21, P22, P31, P32, P41, and P42 into inherent coordinate values. That is, the conversion unit 114 substitutes the latitude and longitude coordinate values ​​of each of the definition points P11, P12, P21, P22, P31, P32, P41, and P42 into Lon and Lat of the conversion formula to calculate inherent coordinate values ​​(x, y).

[0060] The setting unit 115 sets the detection areas 30A, 30B, and 30C in the radio wave sensor based on the unique coordinate values ​​of each of the definition points P11, P12, P21, P22, P31, P32, P41, and P42. Specifically, the setting unit 115 generates setting data for setting the detection areas 30A, 30B, and 30C, and transmits the generated setting data to the radio wave sensor 10. The setting data includes the unique coordinate values ​​of each of the definition points P11, P12, P21, P22, P31, P32, P41, and P42. The radio wave sensor 10 receives the setting data and sets the detection areas 30A, 30B, and 30C based on the setting data.

[0061] 4. Setting Operation of Detection Area Hereinafter, a description will be given of a setting operation of a detection area using the setting device 100. Fig. 7 is a flowchart showing an example of the procedure for setting an detection area.

[0062] Before energizing and activating the radio wave sensor 10, the user determines two specific points P1 and P2 and measures the latitude and longitude coordinate values ​​of the specific points P1 and P2 using a GNSS receiver (step S1). Furthermore, before energizing and activating the radio wave sensor 10, the user determines definition points P11, P12, P21, P22, P31, P32, P41, and P42 and measures the latitude and longitude coordinate values ​​of the definition points P11, P12, P21, P22, P31, P32, P41, and P42 using the GNSS receiver (step S2).

[0063] The user turns on the radio wave sensor 10 and starts it up (step S3), which puts the radio wave sensor 10 into a state where it can detect an object.

[0064] The user places the reference object 300 at at least the specific point P2 of the specific points P1 and P2, and causes the radio wave sensor 10 to detect the reference object. The radio wave sensor 10 detects the reference object 300 and measures the intrinsic coordinate values ​​of the reference object (i.e., the specific point P2) (step S4). Note that if the specific point P1 is the origin of the intrinsic coordinate system (directly below the radio wave sensor 10), there is no need to measure the intrinsic coordinate values ​​of the specific point P1. However, if the specific point P1 is a point other than the origin of the intrinsic coordinate system, the user places the reference object 300 at the specific point P1, and the radio wave sensor 10 also measures the intrinsic coordinate values ​​of the specific point P1.

[0065] The user connects the setting device 100 to the radio wave sensor 10. The setting device 100 generates a conversion formula for converting coordinates between latitude and longitude coordinate values ​​and inherent coordinate values ​​(step S5).

[0066] The user inputs the latitude and longitude coordinate values ​​of the definition points P11, P12, P21, P22, P31, P32, P41, and P42 into the setting device 100. The setting device 100 converts the latitude and longitude coordinate values ​​of the definition points P11, P12, P21, P22, P31, P32, P41, and P42 into unique coordinate values ​​and sets the detection areas 30A, 30B, and 30C in the radio wave sensor 10 (step S6). This completes the detection area setting process.

[0067] The setting device 100 executes a conversion formula generation process in step S5. Fig. 8 is a flowchart showing an example of the conversion formula generation process.

[0068] The user inputs the latitude and longitude coordinate values ​​of the specific points P1 and P2 measured by the GNSS receiver to the setting device 100. The processor 101 of the setting device 100 accepts the input latitude and longitude coordinate values ​​of the specific points P1 and P2 (step S101).

[0069] The radio wave sensor 10 transmits at least the unique coordinate values ​​of the specific point P2. The setting device 100 receives at least the unique coordinate values ​​of the specific point P2 (step S102). If the specific point P1 is set as the origin of the unique coordinate system, the processor 101 reads the unique coordinate values ​​of the specific point P1 from, for example, the non-volatile memory 102. For example, if the origin is defined as the unique coordinate values ​​of the specific point P1 in the setting program 107, the processor 101 does not need to read the unique coordinate values ​​of the specific point P1 from the non-volatile memory 102.

[0070] The processor 101 corrects the unique coordinate values ​​of the specific point P2 based on the installation height H of the radio wave sensor 10 (step S103).

[0071] The processor 101 generates a transformation formula based on the latitude and longitude coordinate values ​​of the specific points P1 and P2 and the unique coordinate values ​​of the specific points P1 and P2 (step S104). Specifically, the processor 101 determines the above-mentioned parameters θ, L1, and L2.

[0072] The processor 101 stores the determined parameters θ, L1, and L2 in the nonvolatile memory 102 and memorizes the conversion formula (step S105). This completes the conversion formula generation process.

[0073] The setting device 100 executes a detection area setting process in step S6. Fig. 9 is a flowchart showing an example of the detection area setting process.

[0074] The user inputs the latitude and longitude coordinate values ​​of the definition points P11, P12, P21, P22, P31, P32, P41, and P42 measured by the GNSS receiver into the setting device 100. The processor 101 of the setting device 100 accepts the input latitude and longitude coordinate values ​​of the definition points P11, P12, P21, P22, P31, P32, P41, and P42 (step S201).

[0075] The processor 101 converts the latitude and longitude coordinate values ​​of the definition points P11, P12, P21, P22, P31, P32, P41, and P42 into unique coordinate values ​​using a conversion formula (step S202).

[0076] The processor 101 generates setting data including the unique coordinate values ​​of the definition points P11, P12, P21, P22, P31, P32, P41, and P42. The processor 101 transmits the generated setting data to the radio wave sensor 10, and sets the detection areas 30A, 30B, and 30C in the radio wave sensor 10 (step S203). This completes the detection area setting process.

[0077] [5. Modifications] In the above-described embodiment, the latitude and longitude coordinate values ​​of the definition points P11, P12, P21, P22, P31, P32, P41, and P42 are converted into intrinsic coordinate values. However, this is not limiting. For example, coordinate values ​​of the definition points P11, P12, P21, P22, P31, P32, P41, and P42 in a coordinate system other than the latitude and longitude coordinate system may be converted into intrinsic coordinate values. In a specific example, a coordinate system defined in an aerial photograph, such as the pixel coordinate system of the aerial photograph image, may be used. In this example, the user identifies the coordinate values ​​of the specific points P1 and P2 in the pixel coordinate system (hereinafter also referred to as "pixel coordinate values") from the aerial photograph image and measures the intrinsic coordinate values ​​of the specific points P1 and P2 using the radio wave sensor 10. The setting device 100 generates a conversion formula for converting pixel coordinate values ​​into intrinsic coordinate values ​​based on the pixel coordinate values ​​and intrinsic coordinate values ​​of the specific points P1 and P2. The user specifies pixel coordinate values ​​of definition points P11, P12, P21, P22, P31, P32, P41, and P42 from the aerial photograph image and inputs the specified pixel coordinate values ​​to the setting device 100. The setting device 100 converts the input pixel coordinate values ​​of definition points P11, P12, P21, P22, P31, P32, P41, and P42 into inherent coordinate values ​​using a conversion formula, and sets detection areas 30A, 30B, and 30C in the radio wave sensor 10 based on the converted inherent coordinate values.

[0078] In the above-described embodiment, the latitude and longitude coordinate values ​​of the definition points P11, P12, P21, P22, P31, P32, P41, and P42 are converted into unique coordinate values ​​using the setting device 100, which is separate from the radio wave sensor 10. However, this is not limiting. For example, the function of the setting device 100 may be provided in the radio wave sensor 10, and the radio wave sensor 10 may convert the latitude and longitude coordinate values ​​of the definition points P11, P12, P21, P22, P31, P32, P41, and P42 into unique coordinate values. Furthermore, in this case, the radio wave sensor 10 may generate the conversion formula.

[0079] [6. Supplementary Note] The embodiments disclosed herein are illustrative in all respects and are not restrictive. The scope of the present invention is defined by the claims, not the above-described embodiments, and includes meanings equivalent to the claims and all modifications within the scope thereof.

[0080] 10 Radio wave sensor 20 Crosswalk 30A, 30B, 30C Detection area 40 Radio wave irradiation range 50 Structure 51 Pole 52 Arm 100 Setting device 101 Processor 102 Non-volatile memory 103 Volatile memory 104 Input device 105 Display device 106 Communication interface (communication I / F) 107 Setting program 110 Input unit 111 Receiving unit 112 Correction unit 113 Generation unit 114 Conversion unit 115 Setting unit 300 Reference object P1, P2 Specific points P11, P12, P21, P22, P31, P32, P41, P42 Definition points

Claims

1. A method for setting a detection area defined on a road in a radio wave sensor, comprising the steps of: acquiring coordinate values ​​in a latitude / longitude coordinate system for each of a plurality of definition points that define the detection area; converting, for each of the plurality of definition points, coordinate values ​​of the latitude and longitude coordinate system into coordinate values ​​of a unique coordinate system used in the radio wave sensor; setting the detection area in the radio wave sensor based on coordinate values ​​of the unique coordinate system of each of the plurality of definition points; Including, How to configure the radio sensor.

2. generating a conversion equation for converting the coordinate values ​​of the latitude-longitude coordinate system into the coordinate values ​​of the intrinsic coordinate system based on the coordinate values ​​of the latitude-longitude coordinate system and the coordinate values ​​of the intrinsic coordinate system for a plurality of points; The method for setting the radio wave sensor according to claim 1 .

3. the plurality of points used to generate the transformation equation are different from the plurality of definition points; The method for setting a radio wave sensor according to claim 2 .

4. The plurality of points used to generate the transformation equation include the origin of the unique coordinate system. The method for setting a radio wave sensor according to claim 2 .

5. The plurality of points used to generate the transformation equation further includes points on coordinate axes other than the origin in the inherent coordinate system. The method for setting a radio wave sensor according to claim 4.

6. The coordinate axes extend along a reference line that is an intersection line between a vertical plane including the radio wave irradiation axis of the radio wave sensor and the ground. The method for setting a radio wave sensor according to claim 5.

7. The method for setting the radio wave sensor includes: acquiring coordinate values ​​of the latitude and longitude coordinate system for the plurality of points used to generate the transformation equation; a step of detecting a reference object disposed at each of the plurality of points used in generating the transformation equation by the radio wave sensor, thereby acquiring coordinate values ​​of a unique coordinate system of the plurality of points used in generating the transformation equation; Further comprising: The method for setting the radio wave sensor according to any one of claims 2 to 6.

8. In the step of acquiring the coordinate values ​​of the inherent coordinate system, a measurement value of a distance to the reference object measured by the radio wave sensor is corrected based on a height of the radio wave sensor from the ground to acquire coordinate values ​​of the inherent coordinate system of the plurality of points used for generating the conversion equation. The method for setting a radio wave sensor according to claim 7.

9. In the step of acquiring coordinate values ​​in the latitude and longitude coordinate system, before activating the radio wave sensor, coordinate values ​​in the latitude and longitude coordinate system for the plurality of points used in generating the conversion equation are acquired. The method for setting a radio wave sensor according to claim 7.

10. A setting device for setting a detection area defined on a road in a radio wave sensor, an input unit that receives coordinate values ​​in a latitude and longitude coordinate system at each of a plurality of definition points that define the detection area; a conversion unit that converts, for each of the plurality of definition points, a coordinate value of the latitude and longitude coordinate system into a coordinate value of a specific coordinate system used in the radio wave sensor; a setting unit that sets the detection area in the radio wave sensor based on coordinate values ​​of each of the plurality of definition points in the unique coordinate system; Equipped with Setting device.

11. A computer program for setting a detection area defined on a road in a radio wave sensor, On the computer, acquiring coordinate values ​​in a latitude / longitude coordinate system for each of a plurality of definition points that define the detection area; converting, for each of the plurality of definition points, coordinate values ​​of the latitude and longitude coordinate system into coordinate values ​​of a unique coordinate system used in the radio wave sensor; setting the detection area in the radio wave sensor based on coordinate values ​​of the unique coordinate system of each of the plurality of definition points; In order to execute Computer program.