How to calibrate the radio wave sensor

Abstract

This method is for adjusting a radio wave sensor that transmits radio waves to a reference object which includes a reflection part, and that receives reflected radio waves which are the radio waves reflected by the reflection part, the method comprising: at least one step among a step for moving the reference object and a step for moving the reflection part such that a temporal change is produced in detection data obtained from the reflected waves; and a step for distinguishing between the reflected waves and noise by using said temporal change in the detection data.

Description

[Technical Field]

[0001] This disclosure relates to a method for adjusting a radio wave sensor, a processing device, and a computer program. This application claims priority to Japanese Patent Application No. 2020-041167, filed on March 10, 2020, and incorporates by reference all of the contents of said Japanese application. [Background technology]

[0002] Patent Document 1 discloses a radio wave sensor that emits radio waves in a target area set to include a crosswalk and detects objects. Patent Document 2 discloses recognizing deviations in the direction of the radio wave sensor by measuring the direction of a reference object installed in a target area set to include a crosswalk. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-90138 [Patent Document 2] Japanese Patent Application Publication No. 2018-162977 Summary of the Invention

[0004] One aspect of the present disclosure is a method for adjusting a radio wave sensor that transmits radio waves to a reference object having a reflecting unit and receives reflected waves, which are radio waves reflected by the reflecting unit, and includes at least one of a step of moving the reference object and a step of moving the reflecting unit so that detection data obtained from the reflected waves changes over time, and a step of distinguishing the reflected waves from noise using the change in the detection data over time.

[0005] Another aspect of the present disclosure is a processing device, which is used in a method for adjusting a radio wave sensor, the method including at least one of moving a reference object having a reflecting unit and moving the reflecting unit so that a temporal change occurs in detection data obtained from reflected waves, which are radio waves transmitted to the reference object and reflected by the reflecting unit, The apparatus further includes a determination unit configured to distinguish between the reflected wave and noise using the temporal change in the detection data.

[0006] Another aspect of the present disclosure is a computer program for operating a computer as a processing device used in a method for adjusting a radio wave sensor, the method including at least one of moving a reference object having a reflecting unit and moving the reflecting unit so that a temporal change occurs in detection data obtained from reflected waves, which are radio waves transmitted to the reference object and reflected by the reflecting unit, and causing a processor of the computer to execute an operation for distinguishing the reflected waves from noise using the temporal change in the detection data. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing a radio wave sensor and a crosswalk near the radio wave sensor. [Figure 2] FIG. 2 is a configuration diagram of the radio wave sensor, the processing device, and the reference device. [Figure 3] FIG. 3 is a flowchart of the radio wave sensor installation work. [Figure 4] FIG. 4 is an explanatory diagram of the installation work of the radio wave sensor. [Figure 5] FIG. 5 is an explanatory diagram of the installation work of the radio wave sensor. [Figure 6] FIG. 6 is an explanatory diagram of the installation work of the radio wave sensor. [Figure 7] FIG. 7 is a diagram showing a radio wave sensor and a crosswalk near the radio wave sensor. [Figure 8]FIG. 8 shows the detection result screen of the radio wave sensor. [Figure 9] FIG. 9 is a flowchart of the first example. [Figure 10] FIG. 10 is an explanatory diagram of the first example. [Figure 11] FIG. 11 is a flowchart of the first example. [Figure 12] FIG. 12 is a flowchart of the second example. [Figure 13] FIG. 13 is an explanatory diagram of the second example. [Figure 14] FIG. 14 is an explanatory diagram of the second example. [Figure 15] FIG. 15 is an explanatory diagram of the second example. [Figure 16] FIG. 16 is a diagram showing periodically changing reflection intensity. [Figure 17] FIG. 17 is a flowchart of the second example. [Figure 18] FIG. 18 is a flowchart of the third example. DETAILED DESCRIPTION OF THE INVENTION

[0008] [Problem to be solved by this disclosure]

[0009] As disclosed in Patent Document 2, when adjusting the orientation of a radio wave sensor, a reference object is installed at a predetermined position, such as a reference position. The reference object is detected by the radio wave sensor in order to adjust the radio wave sensor. However, in a situation where an object other than the reference object is present near the position where the reference object is installed, the radio wave sensor receives not only reflected waves from the reference object but also reflected waves (noise) from the other objects. For this reason, it may be difficult to distinguish between the reference object and objects other than the reference object. In other words, it may be difficult to distinguish between reflected waves from the reference object and noise.

[0010] For example, if the target area includes a crosswalk and many pedestrians are present on the crosswalk, even if a reference object is installed at the reference position where the reference object should be installed, many pedestrians will be present at positions other than the reference position. This makes it difficult to identify which of the many objects detected by the radio wave sensor is the reference object. If the reference object cannot be identified separately from other objects, for example, it will be impossible to determine the coordinates corresponding to the reference position where the reference object is installed in the coordinate system of the radio wave sensor.

[0011] Therefore, when adjusting a radio wave sensor based on the radio wave reflected by a reference object, it is desirable to make it easier to distinguish between the reflected wave and noise.

[0012] [Effects of this disclosure] According to the present disclosure, when adjusting a radio wave sensor based on radio waves reflected by a reference object, it is possible to easily distinguish between reflected waves and noise.

[0013] [Description of the embodiments of the present disclosure]

[0014] (1) A method according to an embodiment is a method for adjusting a radio wave sensor that transmits radio waves to a reference object having a reflecting unit and receives reflected waves, which are radio waves reflected by the reflecting unit, and includes at least one of moving the reference object and moving the reflecting unit so that temporal changes occur in detection data obtained from the reflected waves, and distinguishing the reflected waves from noise using the temporal changes in the detection data. In this case, the detection data obtained from the reflected waves changes over time depending on the movement of the reference object or the reflecting unit, making it easy to distinguish between reflected waves and noise.

[0015] (2) The step of moving the reference object or the step of moving the reflecting unit may include moving the reference object or the reflecting unit so as to cause a temporal change in at least one of the radio wave intensity and the phase of the reflected wave. In this case, the reflected wave can be distinguished from noise by the temporal change in the radio wave intensity or the phase.

[0016] (3) The step of moving the reflecting unit may include periodically moving the reflecting unit. In this case, the change in the detection data over time also becomes periodic, making it easier to distinguish reflected waves from noise.

[0017] (4) The step of moving the reflecting unit may include moving the reflecting unit while maintaining the position of the reference object. In this case, the reflected wave can be distinguished from noise by the movement while maintaining the position.

[0018] (5) The step of moving the reference object may include moving the reference object so that the position of the reference object changes. In this case, the change in position makes it possible to distinguish reflected waves from noise.

[0019] (6) A method according to an embodiment may include a step of moving the reference object and a step of moving the reflecting unit, wherein the step of moving the reflecting unit includes moving the reflecting unit while maintaining a position of the reference object, and the step of moving the reference object may include moving the reference object so that the position of the reference object changes. In this case, it is possible to distinguish reflected waves from noise by both the movement while maintaining the position and the change in position.

[0020] (7) In the method according to the embodiment, the reflecting unit may be moved while maintaining the position of the reference object, and then the reference object may be moved so as to change its position. In this case, the reflected wave and noise can be distinguished by the movement while maintaining the position, and then the reflected wave and noise can be reliably distinguished by the change in position.

[0021] (8) Moving the reflecting unit while maintaining the position of the reference object may include moving the reflecting unit at a reference position, and the reference position may be a position where the reference object is installed for adjusting the radio wave sensor. In this case, the reference position can be recognized by recognizing the reference object.

[0022] (9) Moving the reference object so as to change its position includes moving the reference object from a position other than a reference position to the reference position, and the reference position may be a position where the reference object is installed for adjusting the radio wave sensor. In this case, the reference position can be recognized by moving the reference object.

[0023] (10) The method according to the embodiment may further include a step of outputting the change in the detection data over time. The output may be, for example, a display on a display or an audio output. By outputting the change in the detection data over time, an operator can understand the change in the detection data over time.

[0024] (11) The detection data may include at least one data selected from the group consisting of data indicating the radio wave intensity of the reflected wave, data indicating the phase of the reflected wave, and data indicating the position of the reference object. In this case, the reflected wave is distinguished from noise using these data.

[0025] (12) The step of distinguishing between the reflected wave and the noise may be performed by a processing device that executes a process for distinguishing between the reflected wave and the noise. In this case, the discrimination can be performed efficiently by the processing device.

[0026] (13) The processing may include the processing device determining whether the temporal change in the detection data follows a predetermined movement of the reference object or the reflecting part, which makes it easier to distinguish between reflected waves and noise.

[0027] (14) A processing device according to an embodiment is a processing device used in a method for adjusting a radio wave sensor, which includes at least one of a step of moving a reference object having a reflecting unit and a step of moving the reflecting unit so that a temporal change occurs in detection data obtained from reflected waves, which are radio waves transmitted to the reference object and reflected by the reflecting unit, and which includes a determination unit configured to distinguish between the reflected waves and noise using the temporal change in the detection data.

[0028] (15) A computer program according to an embodiment is a computer program for operating a computer as a processing device used in a method for adjusting a radio wave sensor, the method including at least one of moving a reference object having a reflecting unit and moving the reflecting unit so that a temporal change occurs in detection data obtained from reflected waves, which are radio waves transmitted to the reference object and reflected by the reflecting unit, and causing the computer to execute a process for distinguishing between the reflected waves and noise using the temporal change in the detection data. The computer program is stored in a computer-readable, non-transitory storage medium.

[0029] [Details of the embodiments of the present disclosure]

[0030] 1 shows a radio wave sensor 10 adjusted by the adjustment method according to the embodiment and a crosswalk 110 included in a target area 100 for detection by the radio wave sensor 10. Note that the target area 100 is not limited to an area that includes the crosswalk 110.

[0031] The radio wave sensor 10 of the embodiment is installed to detect objects within a target area 100. The radio wave sensor 10 of the embodiment is infrastructure (road equipment) installed on or near a road, and detects objects such as pedestrians. The radio wave sensor 10 is installed at a relatively high position, supported by an appropriate support member 10A such as a traffic signal pole. The target area 100 is a range set in the radio wave sensor 10 as a range in which object detection is required, within the range in which the radio wave sensor 10 can detect objects.

[0032] Objects detected by the radio wave sensor 10 are, for example, pedestrians, bicycles, motorcycles, guardrails, utility poles, and signs. The target area 100 is set to include a crosswalk 110 and parts of sidewalks 111 and 112. The crosswalk 110 is provided to connect the sidewalks 111 and 112. The crosswalk 110 is also provided to cross a roadway 113 between the sidewalks 111 and 112. The sidewalks 111 and 112 included in the target area 100 are areas adjacent to the crosswalk 110, where pedestrians wait to cross the crosswalk 110.

[0033] The shape of the target area 100 is, for example, a rectangle as shown in Fig. 1. The rectangle-shaped target area 100 has four area edges 100A, 100B, 100C, and 100D. The shape of the target area 100 is not particularly limited. The shape of the target area 100 is determined appropriately based on the shape of the crosswalk 110, the shapes of the sidewalks 111 and 112, and the shape of the roadway 113.

[0034] The radio wave sensor 10 according to the embodiment detects an object by transmitting radio waves and receiving reflected waves from the object. The radio wave sensor 10 according to the embodiment is, for example, a millimeter-wave radar. As shown in FIG. 2 , the radio wave sensor 10 includes a transmitter 11 and a receiver 12.

[0035] The transmitter 11 has a transmitting antenna and a transmitting circuit, and transmits a signal for object detection as a radio wave. The transmitted signal is, for example, a frequency modulated continuous wave (FMCW). The transmitted signal is reflected by an object and becomes a reflected wave.

[0036] The receiver 12 has a receiving antenna and a receiving circuit, and receives the reflected wave from the object. The receiver 12 outputs a signal of the reflected wave to a signal processing circuit 13 provided in the radio wave sensor 10.

[0037] Based on the reflected wave signal, the signal processing circuit 13 generates detection data indicating the distance from the radio wave sensor 10 to the object, the direction of the object relative to the radio wave sensor 10, the speed of the object, the intensity of the reflected wave from the object, the phase of the reflected wave, etc. The radio wave sensor 10 can output the detection data to the outside of the radio wave sensor 10 via a communication interface 14. The communication interface 14 is used to connect to external devices such as a processing device 30 described below. The communication interface 14 may be a wireless communication interface or a wired communication interface.

[0038] The processing device 30 is used to adjust the radio wave sensor 10 when installing or maintaining the radio wave sensor 10. Adjustment of the radio wave sensor 10 includes, for example, adjusting the orientation of the radio wave sensor 10 or adjusting the settings of the radio wave sensor 10. The processing device 30 receives object detection data from the radio wave sensor 10 in order to adjust the radio wave sensor 10. As an example, the processing device 30 is used by being connected to the radio wave sensor 10 so as to be able to communicate with it, but it may also be provided within the radio wave sensor 10 itself.

[0039] As shown in FIG. 2 , the processing device 30 is configured by a computer including a processor 31 and a storage device 32 connected to the processor 31. The storage device 32 in the embodiment includes a primary storage device and a secondary storage device. The primary storage device is, for example, a random access memory (RAM) made of semiconductor memory. The secondary storage device is, for example, a hard disk drive or a solid-state drive. In the present disclosure, the storage device 32 may also be referred to as a memory. The storage device 32 stores a computer program 32A for causing the processor 31 to execute a process for adjusting the radio wave sensor 10. The processor 31 reads and executes the computer program 32A from the storage device 32, thereby executing the process for adjusting the radio wave sensor 10. In the embodiment, the process for adjusting the radio wave sensor 10 includes a process based on the detection data acquired from the radio wave sensor 10 and a control process for the reference device 50. The process based on the detection data acquired from the radio wave sensor 10 includes a determination process for distinguishing between reflected waves and noise. The processor 31 that executes the determination process operates as a determination unit 31A that distinguishes between reflected waves and noise.

[0040] The processing device 30 includes a display 33 for presenting necessary information to an adjuster (operator) who operates the processing device 30 to adjust the radio wave sensor 10. The display 33 displays a screen used to adjust the radio wave sensor 10. The processing device 30 also includes a communication interface 34 for connection to the radio wave sensor 10 and external devices such as the reference device 50.

[0041] The reference device 50 is used as a reference object for adjusting the radio wave sensor 10. When adjusting the radio wave sensor 10, the reference device 50 is installed at a predetermined location and is detected by the radio wave sensor 10. The reference device 50 reflects radio waves transmitted from the radio wave sensor 10 for detection by the radio wave sensor 10.

[0042] The reference device 50 includes a reflector whose movement (operation) is controlled by a controller 51. The reflector may be, for example, a reflector 52, or a module including the reflector 52 as one of its components. The reflector 52 is formed of a material that efficiently reflects radio waves. Providing the reflector 52 in the reference device 50 makes it easier for the radio wave sensor 10 to detect the reference device 50. The reflector 52 is made of, for example, metal. The reference device 50 includes a reflector driver 53 that moves the reflector 52. The reflector driver 53 changes the attitude of the reflector 52. The reflector driver 53 includes, for example, a motor. The motor swings the reflector 52, for example, but the movement of the reflector 52 is not limited to swinging.

[0043] The movement of the reflector 52 is preferably a movement that changes over time the intensity of the reflected waves that reach the radio wave sensor 10. For example, if the reflector 52 has a surface that reflects radio waves, the movement that changes over time the intensity of the reflected waves that reach the radio wave sensor 10 is a movement that changes the attitude of the reflector between an attitude in which the reflecting surface faces the radio wave sensor 10 directly and an attitude in which the reflecting surface does not face the radio wave sensor 10 directly.

[0044] The reference device 50 of the embodiment includes a vehicle 54 for self-propelled movement. The vehicle 54 includes wheels or caterpillars driven by a drive source such as an engine or a motor. The location of the reflector 52 (position coordinates on the road) changes depending on the vehicle 54.

[0045] The controller 51 of the reference device 50 controls the movement of the reflector 52 and the movement (movement) of the reference device 50 by the running body 54. The reference device 50 receives commands from an external device such as the processing device 30 and is remotely controlled in accordance with the commands. For communication with the external device, the reference device 50 is provided with a communication interface 55. For example, when the controller 51 of the reference device 50 receives a command to change the attitude of the reflector 52 from the processing device 30, it controls the operation of the reflector driving unit 53 in accordance with the command. Furthermore, when the controller 51 receives a movement command from the processing device 30, it causes the running body 54 to run in accordance with the command.

[0046] 3 to 6 show the steps for installing the radio wave sensor 10. First, in step S11 of Fig. 3, the target area 100 is determined, and in step S12, the installation position of the radio wave sensor 10 is determined. In step S13, the orientation of the radio wave sensor 10 when installed is determined. Steps S11 to S13 are tasks performed on a desk before the installation of the radio wave sensor 10.

[0047] In step S11, the range of the target area 100 is appropriately determined based on the shape of the crosswalk 110, the shapes of the sidewalks 111 and 112, and the shape of the roadway 113 on a map or satellite photograph including the location where the radio wave sensor 10 is installed (see Figure 4).

[0048] In the next step S12, the installation position of the radio wave sensor 10 is determined taking into consideration the presence of components (such as traffic signals) that can serve as support components 10A for the radio wave sensor 10 (see FIG. 4). Furthermore, in step S13, an orientation D (reference direction) for the radio wave sensor 10 at the time of installation is determined based on the directional characteristics of the radio wave sensor 10 so that reflected power is increased throughout the target area 100 (see FIG. 4). In conjunction with determining the orientation D of the radio wave sensor 10, a reference position A that exists in the orientation D to which the radio wave sensor 10 should face is also determined. When the radio wave sensor 10 is installed at the installation site, the orientation of the radio wave sensor 10 is adjusted so that the radio wave sensor 10 faces the reference position A (see FIG. 4).

[0049] Step S14 and subsequent steps are performed at the installation site of the radio wave sensor 10. In step S14, the radio wave sensor 10 is attached to the installation position determined in step S12. The radio wave sensor 10 is attached to a support member 10A such as a traffic signal pole. When the attachment in step S14 is completed, the orientation of the radio wave sensor 10 has not been adjusted. Therefore, when step S14 is completed, the detectable range 500 of the radio wave sensor 10 may not cover the entire target area 100, as shown in FIG. 5.

[0050] In step S15, the orientation (angle) of the radio wave sensor 10 is adjusted. The adjustment of the orientation of the radio wave sensor 10 includes at least one of adjusting the horizontal orientation (angle) and adjusting the vertical orientation (angle) of the radio wave sensor 10. The horizontal orientation is adjusted by the adjuster rotating the radio wave sensor 10 left and right so that the radio wave sensor 10 faces the reference direction D. This adjustment causes the target area 100 to fall within the detectable range 500 of the radio wave sensor 10. The vertical orientation is adjusted by the adjuster rotating the orientation of the radio wave sensor 10 up and down. The vertical orientation is adjusted so that the radio wave sensor 10 faces a depression angle at which the reflected power from the target area 100 is high.

[0051] In step S16, the target area 100 is set in the radio wave sensor 10. The setting in step S15 is performed using the processing device 30 connected to the radio wave sensor 10. In setting the target area 100 in step S15, the target area 100 determined in step S11 is set in the coordinate system of the radio wave sensor 10 after the orientation adjustment.

[0052] To confirm whether the target area 100 has been set correctly, a reference object such as a reference device 50 is placed within the target area 100 near an area edge 100A (reference position), as shown in Fig. 6. Fig. 6 also shows detection result screens 600A and 600B displayed on the display 33 of the processing device 30. The detection result screens 600A and 600B include a sensor display 610 showing the position of the radio wave sensor 10, a target area display 620 showing the target area 100, and a detected object display 630 showing a detected object.

[0053] If the setting of the target area 100 has been performed correctly, the detected object display 630 is located within the target area display 620, as shown on screen 600A in Fig. 6. In this case, the setting of the target area 100 is complete.

[0054] On the other hand, if the target area 100 has not been set correctly, the detected object display 630 will be located outside the target area display 620, as shown on screen 600B in Fig. 6. In this case, the target area 100 needs to be reset. After resetting the target area 100 using the processing device 30, the adjuster checks again whether the target area 100 has been set correctly.

[0055] As described above, when adjusting the orientation of the radio wave sensor 10 and checking the setting of the target area 100, a reference object is placed at a predetermined reference position (such as the reference position in FIG. 4 or the area edge 100A in FIG. 6). The radio wave sensor 100 then detects the reference object placed at the reference position. However, in the case of a crosswalk 110 where many pedestrians are present, it becomes difficult to distinguish between the pedestrians and the reference object. For example, as shown in FIG. 7, assume that pedestrians W1, W2, W3, W4, W5, and W6 are each present in or near the target area 100. In this situation, if a reference object 50A equipped with a reflector 52 is placed at the area edge 100A, the reflected waves from the pedestrians W1, W2, W3, W4, W5, and W6 and the reflected wave from the reflector 52 are detected in the same manner, making it difficult to distinguish between them. The reflected waves from the pedestrians become noise that makes it difficult to distinguish between the reflected waves from the reflector 52. Noise sources are not limited to pedestrians; bicycles, motorcycles, guardrails, signs, utility poles, etc. can also be noise sources.

[0056] 8 shows a detection result screen 600 that is displayed on the display 33 of the processing device 30 when pedestrians W1, W2, W3, W4, W5, and W6 and a reference object 50A are present as shown in FIG. 7. The detection results w1, w2, w3, w4, w5, and w6 in FIG. 8 correspond to the pedestrians W1, W2, W3, W4, W5, and W6 in FIG. 7, respectively. Furthermore, the detection result 50a in FIG. 8 corresponds to the reference object 50A in FIG. 7. On the detection result screen 600, both the pedestrians and the reference object are detected as some kind of object, so it may not be easy to distinguish between them.

[0057] FIG. 9 shows a first example of a method for distinguishing between a pedestrian and a reference object (a method for distinguishing between noise, which is a reflected wave from a pedestrian or the like, and a reflected wave from a reflector). Here, as an example, a reference device 50 according to the embodiment is used as the reference object, and the same applies to second and third examples described later. However, the reference object may also be a person holding a reflector. Also, here, as an example, the reference position where the reference device 50 should be installed is the area edge 100A of the target area 100 shown in FIG. 7.

[0058] First, in step S101 of FIG. 9, the reference device 50 (reference object) moves to position B1 (initial position) away from the area edge 100A, which is the reference position. Position B1 is preferably a position where there are no pedestrians or other reflecting objects. Position B1 is preferably outside the target area 100, where there are few pedestrians and the like. Position B1 is preferably within the detectable range 500 of the radio wave sensor 10. In other words, position B1 is preferably within a range that can be displayed on the detection result screen 600.

[0059] If there is no position where other objects such as pedestrians do not exist (step S102), the reference device 50 waits for a certain time until a position where other objects do not exist is available (step S103). When a position where other objects do not exist is available, the reference device 50 moves to the position where other objects do not exist.

[0060] When the reference device 50 is located at the area edge 100A, which is the reference position, the adjustment staff member who sets the reference position refers to the display 33 of the processing device 30 and recognizes the reference device 50 on the screen 600 (step S104). At this time, the reference device 50 is located at position B1, which is away from the area edge 100A, which is the reference position. Therefore, even if a pedestrian or the like is present near the area edge 100A, the adjustment staff member can easily distinguish between the pedestrian and the reference device 50 on the screen 600. In other words, if detection results w1, w2, w3, w4, w5, and w6 of a pedestrian or the like are not present near the detection result 50a indicating the reference device 50 on the screen 600, it is relatively easy to recognize the presence of the reference device 50 on the screen 600.

[0061] Next, the reference device 50 moves to the area edge 100A, which is the reference position (step S105). The movement path (reference path) of the reference device 50 is preferably determined in advance. When the reference device 50 moves, the detection result 50a indicating the reference device 50 moves on the screen 600, as shown in FIG. 10. This allows the adjuster to check the movement trajectory P of the reference device 50 on the screen 600.

[0062] The reference device 50's movement, such as moving, makes it easier to distinguish it from stationary objects such as utility poles. Moreover, the reference device 50's unique movement makes it easier to distinguish it from other moving objects such as pedestrians. For example, if a reference path along which the reference device 50 moves is determined in advance and the coordinator knows this reference path, the coordinator can easily recognize an object having a movement trajectory P along this reference path as the reference device 50 (step S106). Therefore, the coordinator can reliably distinguish the reference device 50 from other objects such as pedestrians.

[0063] The reference route preferably includes a route that a pedestrian does not normally take. For example, a route that a pedestrian does not normally take is a route that a pedestrian takes while meandering toward the area edge 100A, which is the reference position. By having the reference device 50 move along a route that a pedestrian does not normally take, it becomes easier to distinguish between the reference device 50 and a pedestrian, etc.

[0064] Note that movement of the reference device 50 may cause a change in the phase of the reflected wave over time. The adjuster may recognize the reference device 50 based on the change in the phase of the reflected wave. It is preferable that the change in the phase of the reflected wave has a regularity specific to the reference device 50, which is different from the change in the phase of the reflected wave from a pedestrian or the like. The adjuster may also recognize the reference device 50 based on the intensity of the reflected wave, which changes in accordance with the change in the phase of the reflected wave.

[0065] When the reference device 50 reaches the area edge 100A, which is the reference position, it stops at that position (step S107). When the reference device 50 stops, the display of the detection result 50a of the reference device 50 on the screen 600 also stops. Therefore, the adjustment staff can recognize the stopping position of the reference device 50 on the screen 600 as the position coordinates (reference point) of the reference position in the coordinate system of the radio wave sensor 10 (step S108). In this way, the adjustment staff can easily determine that the reference device 50 has reached the reference position by checking the movement trajectory of the reference device 50.

[0066] 11 shows the communication processing and information processing performed by the processing device 30 and the reference device 50 in the procedure shown in FIG. 9. First, the processing device 30 transmits a first command to the reference device 50 to move the reference device 50 to the initial position B1 (step S201). The reference device 50, having received the first command, moves to the initial position B1 (step S211). Note that the reference device 50 may be installed at the initial position B1 by an adjuster. Furthermore, the processor 31 of the processing device 30 that transmits the first command functions as a command unit that transmits a command to the reference device 50 (reference object) to move the reference object so that a temporal change occurs in the detection data obtained from the reflected waves of the radio waves by the reference object.

[0067] Next, the processing device 30 transmits a second command to the reference device 50 to move the reference device 50 to the area edge 100A, which is the reference position (step S202). The second command may include data indicating a reference path from the initial position to the reference position. The controller 51 of the reference device 50 that has received the second command controls the traveling object 54 to move the reference device 50 along the reference path to the area edge 100A, which is the reference position (step S212). As the reference device 50 moves, the coordinate position of the reference device 50 detected by the radio wave sensor 10 changes. In addition, in the embodiment, the reflector 52 does not move while the reference device 50 moves, but it may move. The processor 31 of the processing device 30 that transmits the second command functions as a command unit that transmits a command to the reference device 50 (reference object) to move the reference object so that a temporal change occurs in the detection data obtained from the radio wave reflected by the reference object.

[0068] In FIG. 11 , the processing device 30 executes a process for recognizing the reference device 50 from among the objects detected by the radio wave sensor 10, distinguishing it from other objects, and for recognizing the reference position. To recognize the reference device 50, the processing device 30 has predetermined reference path data (data indicating the reference movement of the reference object). The processing device 30 acquires detection data from the radio wave sensor 10 and recognizes, from among the objects detected by the radio wave sensor 10, an object that is moving in accordance with the reference path data as the reference device 50 (step S203). Since the detection data includes coordinate data of the detected objects, the processing device 30 recognizes the movement path P of each object based on the temporal change in coordinates indicated by the coordinate data. The processing device 30 then compares the reference path data with the recognized movement path P and recognizes an object moving along the movement path P that is along the reference path as the reference device 50. Note that the processing device 30 may also recognize the reference device 50 by analyzing the temporal change in phase using phase data of the reflected wave included in the detection data. Furthermore, the reference device 50 may be recognized by an adjuster instead of the processing device 30 .

[0069] When the reference device 50 stops at the area edge 100A, which is the reference position, the processing device 30 recognizes the stopping position as the reference position in the coordinate system of the radio wave sensor 10 (step S204). In this way, the processing device 30 can easily recognize the reference position by recognizing the movement trajectory P of the reference device 50. Note that the reference position may be recognized by an adjuster instead of the processing device 30.

[0070] 12 shows a second example of a method for distinguishing between pedestrians and reference objects (a method for distinguishing between noise, which is a wave reflected from a pedestrian or the like, and a wave reflected from a reflector). In this example, the reference position where the reference device 50 should be installed is the area edge 100A of the target area 100.

[0071] In the second example, first, the reference device 50 is placed at the area edge 100A, which is the reference position (step S301). Next, the reflector 52 moves at the reference position (step S302). Here, the movement of the reflector 52 is, for example, a swing including a left-right movement or an up-down movement. The movement of the reflector 52 may also include a forward-backward movement. During the swing, the running object 54 is stopped at the reference position, and therefore the coordinate position of the reference device 50 detected by the radio wave sensor 10 (the position in two-dimensional coordinates on the road surface) is maintained.

[0072] As the reflector 52 swings, the state in which the radio wave reflecting surface of the reflector 52 faces the radio wave sensor 10 is ensured discretely or periodically. When the radio wave reflecting surface of the reflector 52 faces the radio wave sensor 10 directly, a strong reflection intensity is obtained. Because the swinging causes the state in which the radio wave reflecting surface of the reflector 52 faces the radio wave sensor 10 discretely or periodically, a strong reflection intensity is also obtained discretely or periodically (step S303).

[0073] As shown in Figure 13, when the reflector 52 is installed in a fixed position, the radio wave reflecting surface 52a of the reflector 52 may not be correctly oriented toward the radio wave sensor 10. In this case, the reflected wave R of the transmitted wave T from the radio wave sensor 10 will have fewer components directed toward the radio wave sensor 10. As a result, the intensity of the reflected wave R detected by the radio wave sensor 10 will be weak. Therefore, even if a reflector 52 with good reflection efficiency is used, a sufficiently high reflection intensity cannot be obtained, making it difficult to distinguish the reflected wave from other objects such as pedestrians. Furthermore, when the reflector 52 is installed in a fixed position, it will be difficult to distinguish the reflected wave from stationary objects such as utility poles.

[0074] On the other hand, when the reflector 52 is swung as in the second example, the state in which the reflective surface 52a of the reflector 52 faces the radio wave sensor 10 is ensured discretely or periodically, as shown in Fig. 14. During the swinging motion, the intensities of the reflected waves R2 and R3 are weak when the reflective surface 52a faces the radio wave sensor 10, but the intensity of the reflected wave R1 is high when the reflective surface 52a faces the radio wave sensor 10. Therefore, swinging the reflector 52 provides strong reflection intensity discretely or periodically.

[0075] The movement of the reflector 52 may be random or may be a regularly repeated periodic movement. If the movement of the reflector 52 is periodic, the change in reflection intensity will be periodic, making it easier to recognize the reference device 50. FIG. 15 shows a state in which the reflector 52 moves so as to alternate between a state M1 in which the reflective surface 52a of the reflector 52 does not directly face the radio wave sensor 10 and a state M2 in which the reflective surface 52a of the reflector 52 directly faces the radio wave sensor 10 every second. In a state in which the states M1 and M2 alternate every second, a strong reflection intensity is obtained every second, as shown in FIG. 16. The change in reflection intensity has a distinctive pattern that is not generated by reflected waves from ordinary pedestrians, etc., making it easier to recognize the reference device 50 and distinguish it from a pedestrian. Furthermore, the reference device 50's swinging or other movement makes it easier to distinguish it from stationary objects such as utility poles.

[0076] The change in reflection intensity is displayed on the screen 600 so that it can be seen by the adjustment personnel. Therefore, by referring to the screen 600, the adjustment personnel can distinguish an object whose reflection intensity changes in accordance with the movement of the reflector 52 from other objects such as pedestrians and recognize it as the reference device 50. The adjustment personnel can recognize the position of the reference device 50 on the screen 600 as the position coordinates of the reference coordinates in the coordinate system of the radio wave sensor 10 (step S304).

[0077] Note that the phase of the reflected wave may change over time due to the movement of the reflector 52. Therefore, the change in phase may be displayed on the screen 600, and the reference device 50 may be recognized based on the change in phase.

[0078] 17 shows the communication processing and information processing performed by the processing device 30 and the reference device 50 in the procedure shown in FIG. 12. Here, it is assumed that the reference device 50 is installed in advance at the area edge 100A, which is the reference position. The processing device 30 transmits a command to the reference device 50 to swing the reflector 52 (step S401). The controller 51 of the reference device 50, which receives this command, controls the reflector driving unit 53 to cause the reflector 52 to move, for example, swing (step S411).

[0079] In FIG. 17 , the processing device 30 executes a process for recognizing the reference device 50 from among the objects detected by the radio wave sensor 10, distinguishing it from other objects, and recognizing its reference position. To recognize the reference device 50, the processing device 30 has data indicating a predetermined movement pattern of the reflector 52 (data indicating the reference movement of the reference object). The processing device 30 acquires detection data from the radio wave sensor 10 and recognizes, from among the objects detected by the radio wave sensor 10, an object that moves in accordance with the data indicating the movement pattern of the reflector 52 (e.g., a regular movement) as the reference device 50 (step S402). Because the detection data includes data on the reflection intensity from the detected object, the processing device 30 can recognize the reference device 50 from among other objects, such as pedestrians, by analyzing the temporal change in the reflection intensity. Note that the reference device 50 may also be recognized by analyzing the temporal change in phase using data on the phase of the reflected wave included in the detection data.

[0080] When the processing device 30 recognizes the reference device 50, it recognizes the position of the reference device 50 as a reference position in the coordinate system of the radio wave sensor 10 (step S403). In this way, the processing device 30 can easily recognize the reference position by analyzing the change pattern of the reflection intensity.

[0081] FIG. 18 shows a third example of a method for distinguishing between pedestrians and reference objects (a method for distinguishing between noise, which is a wave reflected from a pedestrian or the like, and a wave reflected from a reflector). Here, too, the reference position where the reference device 50 should be installed is the area edge 100A of the target area 100. The third example roughly corresponds to a combination of the first and second examples. For points not specifically explained in the third example, the explanations of the first and second examples are applicable.

[0082] First, the processing device 30 transmits a first command to the reference device 50 to move the reference device 50 to the initial position B1 (step S501). The reference device 50, having received the first command, moves to the initial position B1 (step S511). Next, the processing device 30 transmits a second command to the reference device 50 to swing the reflector 52 (step S502). The controller 51 of the reference device 50, having received the second command, controls the reflector driving unit 53 to cause the reflector 52 to move, for example, swing (step S512). The processing device 30 acquires detection data from the radio wave sensor 10 and recognizes the reference device 50 based on a change in reflection intensity over time (step S503). By swinging the reference device 50 at the initial position B1, the processing device 30 can easily recognize the reference device 50 at the initial position B1.

[0083] Next, the processing device 30 transmits a third command to the reference device 50 to move the reference device 50 to the area edge 100A, which is the reference position (step S504). The third command may include data indicating a reference path from the initial position B1 to the reference position. Upon receiving the third command, the controller of the reference device 50 controls the traveling object 54 to move the reference device 50 along the reference path to the area edge 100A, which is the reference position (step S513).

[0084] The processing device 30 acquires the detection data from the radio wave sensor 10, and recognizes the reference device 50 moving from the initial position B1 while tracking it based on the coordinate data included in the detection data (step S505). In the third example, when the reference device 50 is at the initial position B1 (before moving to the reference position), the reference device 50 has already been recognized as distinct from other objects, so that the current position of the reference device 50 can be determined by tracking the object moving from the initial position B1.

[0085] When the reference device 50 stops at the area edge 100A, the processing device 30 recognizes the position of the area edge 100A as a reference position in the coordinate system of the radio wave sensor 10 (step S506). Note that the reference device 50 may further perform a swinging motion at the reference position.

[0086] As in the third example, the movement of the reference device 50 includes both the movement of the reference device 50 and the swinging of the reflector 52, which makes it easier to recognize the reference device 50.

[0087] It should be noted that the embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the meanings described above, and is intended to include meanings equivalent to the claims and all modifications within the scope thereof.

[0088] [Note]

[0089] The present disclosure includes the following aspects.

[0090] A. A processing device used in a radio wave sensor adjustment method including at least one of a step of moving a reference object having a reflecting unit and a step of moving the reflecting unit so that a temporal change occurs in detection data obtained from reflected waves, which are radio waves transmitted to the reference object and reflected by the reflecting unit, and the processing device includes a determination unit configured to distinguish between the reflected waves and noise using the temporal change in the detection data; The determination unit is configured to distinguish the reflected wave from the noise by determining whether a temporal change in the detection data is a change in accordance with a predetermined movement of the reference object or the reflecting unit. Processing equipment. [Explanation of symbols]

[0091] 10 Radio wave sensor, 10A Support member, 11 Transmitter, 12 Receiver, 13 Signal processing circuit, 14 Communication interface, 30 Processing device, 31 Processor, 31A Determination unit, 32 Storage device, 32A Computer program, 33 Display, 34 Communication interface, 50 Reference device, 50A Reference object, 50a Detection result, 51 Controller, 52 Reflector, 52a Reflective surface, 53 Reflector drive unit, 54 Traveling body, 55 Communication interface, 100 Target area, 100A Area edge, 100B Area edge, 100C Area edge, 100D Area edge, 110 Crosswalk, 111 Sidewalk, 112 Sidewalk, 113 Roadway, 500 Detection range, 600 Detection result screen, 600A Detection result screen, 600B Detection result screen, 610 Sensor display, 620 Target area display, 630 detected object display, A reference position, B1 initial position, D reference direction, M1 state, M2 state, P movement trajectory (movement path), R reflected wave, R1 reflected wave, R2 reflected wave, R3 reflected wave, T transmitted wave, W1 pedestrian, W2 pedestrian, W3 pedestrian, W4 pedestrian, W5 pedestrian, W6 pedestrian, w1 detection result, w2 detection result, w3 detection result, w4 detection result, w5 detection result, w6 detection result

Claims

1. A method for adjusting a radio wave sensor that transmits radio waves to a reference object having a reflecting portion and receives reflected waves that are radio waves reflected by the reflecting portion, At least one of a step of moving the reference object and a step of moving the reflecting unit so that a temporal change known to an adjustment person occurs in the detection data obtained from the reflected wave; distinguishing the reflected wave from noise using the temporal change in the detection data; a step of identifying the reference object based on the reflected wave distinguished from the noise, and having an adjustment staff member recognize the stop position or placement position of the reference object based on the identified reference object as a reference position for adjusting the orientation of the radio wave sensor with respect to the detection target area; a step in which an adjuster adjusts the orientation of the radio wave sensor with respect to the target area based on the recognized reference position; A method for adjusting a radio wave sensor, comprising:

2. The step of moving the reference object or the step of moving the reflecting unit includes moving the reference object or the reflecting unit so that the temporal change occurs in at least one of the radio wave intensity of the reflected wave and the phase of the reflected wave. The method for adjusting a radio wave sensor according to claim 1 .

3. The step of moving the reflecting portion includes periodically moving the reflecting portion. A method for adjusting a radio wave sensor according to claim 1 or 2.

4. The step of moving the reflecting unit includes moving the reflecting unit while maintaining the position of the reference object. A method for adjusting a radio wave sensor according to any one of claims 1 to 3.

5. The step of moving the reference object includes moving the position of the reference object. A method for adjusting a radio wave sensor according to any one of claims 1 to 3.

6. a step of moving the reference object and a step of moving the reflecting unit, the step of moving the reflecting unit includes moving the reflecting unit while maintaining the position of the reference object; The step of moving the reference object includes moving the position of the reference object. A method for adjusting a radio wave sensor according to any one of claims 1 to 3.

7. The reflecting unit is moved while maintaining the position of the reference object, and then the position of the reference object is moved. The method for adjusting a radio wave sensor according to claim 6.

8. Moving the reflecting unit while maintaining the position of the reference object includes moving the reflecting unit at a reference position, the reference position being a position where the reference object is installed for adjusting the radio wave sensor. A method for adjusting a radio wave sensor according to any one of claims 4, 6 and 7.

9. Moving the position of the reference object includes moving the reference object from a position other than a reference position to the reference position, and the reference position is a position where the reference object is installed for adjusting the radio wave sensor. A method for adjusting a radio wave sensor according to any one of claims 5 to 7.

10. outputting the temporal change in the detection data by an output device; The outputting step includes: a step of displaying the temporal change in the detection data on a display unit, or a step of outputting the temporal change in the detection data as audio, A method for adjusting a radio wave sensor according to any one of claims 1 to 9.

11. The detection data includes at least one data selected from the group consisting of data indicating the radio wave intensity of the reflected wave, data indicating the phase of the reflected wave, and data indicating the position of the reference object. A method for adjusting a radio wave sensor according to any one of claims 1 to 10.

12. The step of distinguishing between the reflected wave and the noise is performed by a processing device that executes a process of distinguishing between the reflected wave and the noise. A method for adjusting a radio wave sensor according to any one of claims 1 to 11.

13. The processing includes the processing device determining whether the temporal change in the sensed data follows a predetermined movement of the reference object or the reflecting portion. The method for adjusting a radio wave sensor according to claim 12.

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