Moving body control device and moving body control system

Abstract

To provide a moving body control device and a moving body control system that can automatically travel a moving body without increasing the burden on workers even when a process layout is changed.SOLUTION: A moving body control device 20 is capable of communicating with a plurality of wireless markers M arranged in an area in which a moving body 10 can travel automatically, and includes a setting unit 29, a measurement instruction unit 33, an estimation unit, and a travel instruction unit. The setting unit 29 sets map information related to a travel route 5 of the moving body 10. The measurement instruction unit 33 instructs the wireless marker M to be used to measure a distance between the wireless marker M to be used and the moving body 10. The estimation unit acquires distance information including the measured distance from the wireless marker M to be used, and estimates a position of the moving body 10 based on the acquired distance information. The travel instruction unit automatically drives the moving body 10 along the travel route 5 based on the estimated position of the moving body 10 and map information.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a mobile object control device and a mobile object control system. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there has been known a system in which a moving body such as an automatic guided vehicle (AGV) detects magnetism from magnetic markers laid on a floor surface and automatically travels along a travel route.

[0003] In the system disclosed in Patent Document 1, a first magnetic tape is laid as a magnetic marker in a branching area of ​​a travel route where the route branches, and a second magnetic tape is laid as a magnetic marker in areas other than the branching area. The first magnetic tape has one of a north pole and a south pole, and the second magnetic tape has the other of a north pole and a south pole.

[0004] With this configuration, the mobile object can derive the amount of change in the detected magnetism over time, and determine whether the vehicle is entering or exiting the branch area based on the amount of change in the magnetism that has been derived over time. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2022-163855 A Summary of the Invention [Problem to be solved by the invention]

[0006] In recent years, it has been considered to introduce the above-mentioned system to automate the manufacturing process of wire harnesses.

[0007] In the manufacturing process of wire harnesses, the process layout may change in response to design changes such as changes in vehicle specifications.

[0008] However, in the above-mentioned system, there is a possibility that the magnetic markers may be hidden by process equipment due to changes in the process layout. In this case, the mobile body cannot detect the magnetism of the magnetic tape and cannot travel automatically.

[0009] One way to deal with this problem would be to re-lay the magnetic markers every time the process layout is changed, but this would increase the burden on workers.

[0010] For this reason, further improvements were needed to enable the vehicle to travel automatically without increasing the burden on workers, even when the process layout is changed.

[0011] The present invention has been made in consideration of the problems inherent in the conventional techniques, and an object of the present invention is to provide a mobile body control device and a mobile body control system that can automatically travel a mobile body without increasing the burden on workers even when the process layout is changed. [Means for solving the problem]

[0012] A mobile body control device according to a first aspect of the present invention is capable of communicating with a plurality of wireless markers arranged in an area in which a mobile body can travel automatically, and includes a setting unit that sets map information related to a travel route of the mobile body, a selection unit that selects a plurality of wireless markers to be used from the plurality of wireless markers based on the travel route, a measurement instruction unit that instructs the wireless markers to be used to measure a distance between the wireless markers to be used and the mobile body, an estimation unit that acquires distance information including the measured distance from the wireless marker to be used and estimates a position of the mobile body based on the acquired distance information, and a travel instruction unit that automatically travels the mobile body along the travel route based on the estimated position of the mobile body and the map information.

[0013] A mobile body control system according to a second aspect of the present invention includes a mobile body, a plurality of wireless markers arranged in an area in which the mobile body can travel automatically, and a mobile body control device capable of communicating with the plurality of wireless markers, wherein the mobile body control device includes a setting unit that sets map information regarding a travel route of the mobile body, a selection unit that selects a plurality of wireless markers to be used from the plurality of wireless markers based on the travel route, a measurement instruction unit that instructs the wireless marker to be used to measure a distance between the wireless marker to be used and the mobile body, an estimation unit that acquires distance information including the measured distance from the wireless marker to be used and estimates a position of the mobile body based on the acquired distance information, and a travel instruction unit that automatically travels the mobile body along the travel route based on the estimated position of the mobile body and the map information, and each wireless marker includes a measurement unit that measures the distance to the mobile body based on an instruction from the mobile body control device, and a transmission unit that transmits the distance information including the measured distance to the mobile body control device. Effect of the Invention

[0014] According to the present invention, it is possible to provide a mobile body control device and a mobile body control system that can automatically travel a mobile body without increasing the burden on workers, even when the process layout is changed. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a schematic diagram showing the overall configuration of a mobile object control system according to this embodiment. [Diagram 2] FIG. 2 is a block diagram showing an example of the configuration of a moving body according to this embodiment. [Diagram 3] FIG. 3 is a block diagram showing an example of the functional configuration of the mobile object control device according to the present embodiment. [Figure 4] FIG. 4 is a block diagram showing an example of the functional configuration of the wireless marker according to this embodiment. [Diagram 5]FIG. 5 is a block diagram showing an example of a hardware configuration of the wireless marker according to this embodiment. [Figure 6] FIG. 6 is a diagram for explaining a frame structure of communication data according to this embodiment. [Figure 7] FIG. 7 is a diagram showing an example of a flowchart of a procedure for selecting a wireless marker according to the present embodiment. [Figure 8] FIG. 8 is a diagram for explaining calculation of the elevation angle of the wireless marker according to this embodiment. [Figure 9] FIG. 9 is a diagram for explaining the order determination of wireless markers according to the present embodiment. [Figure 10] FIG. 10 is a diagram showing an example of a flowchart of a control procedure for a moving object according to this embodiment. [Figure 11] FIG. 11 is a diagram showing an example of a distance measurement process sequence according to the present embodiment. [Figure 12] FIG. 12 is a diagram showing an example of a flowchart of the map matching process according to this embodiment. [Figure 13] FIG. 13 is a diagram for explaining map matching according to this embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, the mobile object control system and the mobile object control device according to the present embodiment will be described in detail with reference to the drawings. Note that the same or similar reference numerals are used to designate the same functions and configurations, and the description thereof will be omitted as appropriate.

[0017] [Overall schematic configuration of the mobility control system] First, a configuration of a mobile object control system 1 according to this embodiment will be described. In this embodiment, the mobile object control system 1 is provided in a manufacturing process in a factory 3. The mobile object control system 1 is provided, for example, in a manufacturing process of wire harnesses.

[0018] Fig. 1 is an overall schematic configuration diagram of a mobile object control system 1. As shown in Fig. 1, the mobile object control system 1 includes a mobile object 10, a mobile object control device 20, and wireless markers M1 to M20. In this embodiment, when the wireless markers M1 to M20 are not distinguished from one another, they are simply referred to as wireless marker M. The number of wireless markers M is not limited to 20, and may be a number other than 20 depending on the size of the area in which the mobile object 10 can travel automatically, the accuracy in estimating the position of the mobile object 10, and the like.

[0019] In the mobile object control system 1, the mobile object 10 receives operation instructions from a mobile object control device 20 via one or more wireless markers M, and performs a plurality of manufacturing tasks while traveling automatically. The mobile object 10 is, for example, an automatic guided vehicle (AGV: Auto Guided Vehicle).

[0020] The mobile object control device 20 is provided in the factory 3 and is communicatively connected to the wireless marker M1. The mobile object control device 20 may be provided outside the factory 3 as long as it is communicatively connected to the wireless marker M1.

[0021] In this embodiment, the mobile object control device 20 is indirectly communicatively connected to each of the wireless markers M2 to M20 via one or more other wireless markers M including the wireless marker M1. The mobile object control device 20 may be directly communicatively connected to each of the wireless markers M2 to M20.

[0022] When an operator determines a travel route 5 along which the mobile body 10 will automatically travel based on the layout of the manufacturing process, the mobile body control device 20 sets map information relating to the travel route 5 through the operator's operation. Specifically, the mobile body control device 20 sets the travel route 5 on map data within the factory 3 that has been stored in advance. Based on the travel route 5, the mobile body control device 20 selects multiple wireless markers M to be used for estimating the position of the mobile body 10 from the wireless markers M1 to M20.

[0023] The mobile object control device 20 acquires distance information from a predetermined number of wireless markers M among the selected wireless markers M, and estimates the position of the mobile object 10 based on the acquired distance information. The mobile object control device 20 generates operation instructions for the mobile object 10 based on the estimated position of the mobile object 10 and map information related to the travel route 5, and automatically drives the mobile object 10 along the travel route 5.

[0024] The wireless markers M1 to M20 are placed in an area in the factory 3 where the mobile object 10 can travel automatically. In this embodiment, the wireless markers M1 to M20 are placed above the area (for example, on the ceiling of the factory 3 located above the area). Note that the placement of the wireless markers M1 to M20 is not limited to above the area, and may be below the area or buried in the ground of the area.

[0025] When the wireless markers M1 to M20 are placed below the area or buried in the ground of the area, some of the wireless markers M1 to M20 may be hidden by process equipment due to changes in the process layout, which may impede wireless communication with the moving body 10. However, as described below, since the positioning of the moving body 10 is performed using a plurality of wireless markers M to be used, there is no problem even if some of the wireless markers M1 to M20 are hidden by process equipment.

[0026] In this embodiment, the wireless markers M1 to M20 are arranged in a 5×4 matrix. Specifically, the wireless markers M1 to M4 are arranged in the first row with a distance d1 between them, and the wireless markers M5 to M8 are arranged in the second row with a distance d1 between them. The wireless markers M9 to M12 are arranged in the third row with a distance d1 between them, and the wireless markers M13 to M16 are arranged in the fourth row with a distance d1 between them. The wireless markers M17 to M20 are arranged in the fifth row with a distance d1 between them.

[0027] Moreover, the wireless markers M1, M5, M9, M13, and M17 are arranged in a first row with a distance d2 between them, the wireless markers M2, M6, M10, M14, and M18 are arranged in a second row with a distance d2 between them, the wireless markers M3, M7, M11, M15, and M19 are arranged in a third row with a distance d2 between them, and the wireless markers M4, M8, M12, M16, and M20 are arranged in a fourth row with a distance d2 between them.

[0028] The wireless markers M1 to M20 are not limited to being arranged in a 5×4 matrix, but may be arranged in an m×n matrix with the number of rows m being other than five and the number of columns n being other than four.

[0029] In this embodiment, the row direction of the matrix is ​​defined as the X direction, the column direction of the matrix is ​​defined as the Y direction, and the height direction of the factory 3 is defined as the Z direction (see FIGS. 1, 8, and 9). The X direction, Y direction, and Z direction are mutually perpendicular.

[0030] In this embodiment, numbers 1 to 20 are assigned to the wireless markers M1 to M20 as identification information, respectively.

[0031] Each of the wireless markers M1 to M20 measures the distance to the moving body 10 based on an instruction (request message) from the moving body control device 20, and transmits distance information including the measured distance to the moving body control device 20. When each of the wireless markers M1 to M20 receives an operation instruction for the moving body 10, it transmits the operation instruction to the moving body 10.

[0032] Each of the wireless markers M1 to M20 is communicably connected to the moving object 10 according to the position of the moving object 10. Each of the wireless markers M1 to M20 performs wireless communication with the moving object 10 in accordance with IEEE802.11az or IEEE802.11bf.

[0033] The wireless marker M1 and the mobile object control device 20 are connected to each other so as to be able to communicate with each other. The wireless markers M1 and M2 are connected to each other so as to be able to communicate with each other. The wireless markers M2 and M3 are connected to each other so as to be able to communicate with each other. The wireless markers M3 and M4 are connected to each other so as to be able to communicate with each other. The wireless markers M4 and M8 are connected to each other so as to be able to communicate with each other.

[0034] The wireless markers M7 and M8 are connected to each other so as to be able to communicate with each other. The wireless markers M6 and M7 are connected to each other so as to be able to communicate with each other. The wireless markers M5 and M6 are connected to each other so as to be able to communicate with each other. The wireless markers M5 and M9 are connected to each other so as to be able to communicate with each other.

[0035] The wireless markers M9 and M10 are connected to each other so as to be able to communicate with each other. The wireless markers M10 and M11 are connected to each other so as to be able to communicate with each other. The wireless markers M11 and M12 are connected to each other so as to be able to communicate with each other. The wireless markers M12 and M16 are connected to each other so as to be able to communicate with each other.

[0036] The wireless markers M15 and M16 are connected to each other so as to be able to communicate with each other. The wireless markers M14 and M15 are connected to each other so as to be able to communicate with each other. The wireless markers M13 and M14 are connected to each other so as to be able to communicate with each other. The wireless markers M13 and M17 are connected to each other so as to be able to communicate with each other.

[0037] The wireless markers M17 and M18 are connected to each other so as to be able to communicate with each other. The wireless markers M18 and M19 are connected to each other so as to be able to communicate with each other. The wireless markers M19 and M20 are connected to each other so as to be able to communicate with each other.

[0038] With this configuration, a communication path is formed within factory 3 in the following order: wireless markers M1, M2, M3, M4, M8, M7, M6, M5, M9, M10, M11, M12, M16, M15, M14, M13, M17, M18, M19, and M20.

[0039] For example, when the wireless marker M3 transmits distance information to the mobile object control device 20, the distance information is relayed in the order of wireless markers M2 and M1, and then transmitted from the wireless marker M3 to the mobile object control device 20. Similarly, when the mobile object control device 20 transmits an operation instruction for the mobile object 10 to the wireless marker M3, the operation instruction is relayed in the order of wireless markers M1 and M2, and then transmitted from the mobile object control device 20 to the wireless marker M3.

[0040] In this embodiment, the travel route 5 has points P1 to P4 where the traveling direction of the moving body 10 is changed. As described later, at each of the points P1 to P4, the position of the moving body 10 is measured and an operation instruction is transmitted to the moving body 10. The points P1 to P4 are also called measurement points.

[0041] In the travel route 5, a route P1-P2 between the points P1 and P2 is parallel to the X-axis, and wireless markers M1 to M4 are located above the route P1-P2. A route P2-P3 between the points P2 and P3 is parallel to the Y-axis, and wireless markers M4 and M8 are located above the route P2-P3.

[0042] A path P3-P4 between the point P3 and the point P4 is parallel to the X-axis, and wireless markers M5 to M8 are located above the path P3-P4. A path P4-P1 between the point P4 and the point P1 is parallel to the Y-axis, and wireless markers M1 and M5 are located above the path P4-P1.

[0043] The travel path 5 is not limited to the above-mentioned path, and can be set appropriately according to the layout of the manufacturing process. Meanwhile, the arrangement of the wireless markers M1 to M20 is fixed. Therefore, the positional relationship between the travel path 5 and the wireless markers M1 to M20 is changed according to the layout of the manufacturing process.

[0044] [Mobile configuration] Next, a description will be given of the configuration of the mobile object 10. Fig. 2 is a block diagram showing an example of the configuration of the mobile object 10. As shown in Fig. 2, the mobile object 10 includes a wireless communication device 11, an RTC (REAL-TIME CLOCK) 13, and a control device 15.

[0045] The wireless communication device 11 performs wireless communication conforming to IEEE802.11az or IEEE802.11bf with the wireless markers M. The wireless communication device 11 receives an operation instruction from the mobile object control device 20 via one or more wireless markers M.

[0046] When wireless communication conforming to IEEE802.11az is performed between the wireless communication device 11 and the wireless marker M, when the wireless communication device 11 receives a measurement frame from the wireless marker M, it transmits a report frame to the wireless marker M in response to the measurement frame.

[0047] In wireless communication conforming to IEEE802.11az, the measurement frames and the report frames are transmitted and received according to a Fine Timing Measurement (FTM) protocol. For this reason, the measurement frames and the report frames are also called FTM frames.

[0048] The RTC 13 generates the time for the mobile unit 10 based on an internal clock.

[0049] The control device 15 adjusts the moving speed and moving direction of the moving body 10 based on the operation instructions transmitted from the moving body control device 20, and causes the moving body 10 to move forward, backward, turn left, turn right, stop, etc. Through such control, the moving body 10 performs automatic traveling.

[0050] When wireless communication conforming to IEEE802.11az is performed between the wireless communication device 11 and the wireless marker M, the control device 15 generates a report frame when the wireless communication device 11 receives a measurement frame. When the control device 15 generates the report frame, the control device 15 causes the wireless communication device 11 to transmit the report frame to the wireless marker M, with the report frame including the reception time of the measurement frame.

[0051] In addition, when the control device 15 generates a report frame, instead of including the reception time of the measurement frame in the report frame, the control device 15 may include the transmission time of the report frame in the report frame and have the wireless communication device 11 transmit the report frame toward the wireless marker M.

[0052] [Configuration of mobile control device] Next, the configuration of the mobile object control device 20 will be described. Fig. 3 is a block diagram showing an example of the functional configuration of the mobile object control device 20. As shown in Fig. 3, the mobile object control device 20 includes a wireless transmission unit 21, a wireless reception unit 23, a control unit 25, a storage unit 27, a setting unit 29, a selection unit 31, a measurement instruction unit 33, a position calculation unit 35, a determination unit 37, a matching execution unit 39, and an instruction unit 41. The configuration that realizes the function of the position calculation unit 35 and the function of the determination unit 37 is also collectively referred to as an estimation unit. The configuration that realizes the function of the matching execution unit 39 and the function of the instruction unit 41 is also collectively referred to as a travel instruction unit.

[0053] The wireless transmission unit 21 transmits a wireless signal to the wireless marker M1. The wireless transmission unit 21 indirectly transmits a wireless signal to each of the wireless markers M2 to M20 via one or more other wireless markers M including the wireless marker M1. The wireless signal is, for example, a synchronization signal, a request message, and an operation instruction for the moving object 10.

[0054] The wireless receiving unit 23 receives a wireless signal from the wireless marker M1. The wireless receiving unit 23 indirectly receives a wireless signal from each of the wireless markers M2 to M20 via one or more other wireless markers M including the wireless marker M1. The wireless signal is, for example, distance information.

[0055] The control unit 25 controls the overall processing in the mobile object control device 20. Specifically, the control unit 25 controls the operation of each of the wireless transmission unit 21, the wireless reception unit 23, the storage unit 27, the setting unit 29, the selection unit 31, the measurement instruction unit 33, the position calculation unit 35, the determination unit 37, the matching execution unit 39, and the instruction unit 41.

[0056] The control unit 25 periodically transmits a synchronization signal to the wireless markers M1 to M20 via the wireless transmission unit 21. Upon receiving the synchronization signal, each of the wireless markers M1 to M20 synchronizes the time of its own device with the synchronization signal. This allows the times of the wireless markers M1 to M20 to be synchronized with one another.

[0057] The memory unit 27 pre-stores control parameters necessary for wireless communication, map data within the factory 3, position information of the wireless markers M1 to M20, addresses of the wireless markers M1 to M20, identification information of the wireless markers M1 to M20, the address of the mobile control device 20, and identification information of the positioning group described later.

[0058] The memory unit 27 stores map information and error ranges related to the travel route 5 set by the setting unit 29, and identification information of the wireless marker M to be used selected by the selection unit 31. The memory unit 27 stores distance information received by the wireless receiving unit 23, the position of the moving body 10 calculated (estimated) by the position calculation unit 35, the current position of the moving body 10 determined by the determination unit 37, etc.

[0059] The setting unit 29 sets map information related to the travel route 5. Specifically, the setting unit 29 sets the travel route 5 on map data within the factory 3 pre-stored in the storage unit 27. As a result, the storage unit 27 stores the map information related to the travel route 5. In this embodiment, the map information related to the travel route 5 includes position information of points P1 to P4 on the travel route 5.

[0060] The setting unit 29 sets an error range that is allowable when estimating the current position of the moving body 10, and stores the error range in the storage unit 27. As described later, the determination unit 37 uses the error range when determining the current position of the moving body 10.

[0061] The selection unit 31 selects a wireless marker M to be used when estimating the position of the moving body 10 from among the wireless markers M1 to M20, based on the travel route 5. The wireless marker M to be used when estimating the position of the moving body 10 is also referred to as a wireless marker M to be used.

[0062] The selection unit 31 first excludes wireless markers M that are hidden by a shadow from the travel route 5 due to an operation by the worker, from the wireless markers M to be used. In this embodiment, it is assumed that there is no wireless marker M that is hidden by a shadow from the travel route 5.

[0063] The selection unit 31 selects a wireless marker M to be used from among the wireless markers M1 to M20 based on the magnitude of the elevation angle of the wireless markers M1 to M20 at the points P1 to P4 on the travel route 5.

[0064] Specifically, the selection unit 31 selects the largest elevation angle among the elevation angles at the points P1 to P4 on the travel route 5 for each wireless marker M. The selection unit 31 excludes, from the wireless markers M1 to M20, wireless markers M having an elevation angle equal to or smaller than a threshold value from the wireless markers M to be used. The selection unit 31 selects, from the wireless markers M1 to M20, wireless markers M having a value larger than the threshold value as the wireless markers M to be used.

[0065] The selection unit 31 stores the identification information of the wireless marker M selected as the wireless marker M to be used in the storage unit 27 as the identification information of the wireless marker M to be used.

[0066] In this embodiment, the angles of elevation of the wireless markers M1 to M20 at the points P1 to P4 on the travel route 5 are regarded as angles of elevation of the wireless markers M1 to M20 as seen from the moving object 10 at the points P1 to P4.

[0067] Here, when the wireless markers M1 to M20 are buried in the ground in an area where the moving body 10 can travel automatically, the selection unit 31 uses the depression angles of the wireless markers M1 to M20 instead of the elevation angles of the wireless markers M1 to M20. The elevation angles and depression angles are collectively referred to as elevation and depression angles.

[0068] When the selection unit 31 selects the wireless marker M to be used based on the travel route 5, the selection unit 31 does not change the selected wireless marker M to be used until the travel route 5 is changed.

[0069] The selection unit 31 groups the plurality of target wireless markers M into a plurality of positioning groups for each of a predetermined number of target wireless markers M in ascending order of elevation angle. In this embodiment, the predetermined number is set to 4. Note that, when the area in which the moving body 10 can automatically travel is narrow, the predetermined number may be a number less than 4.

[0070] In this embodiment, the selection unit 31 groups the first predetermined number of target wireless markers M in order from the largest elevation angle as a first positioning group, and groups the second predetermined number of target wireless markers M in order from the largest elevation angle as a second positioning group. In this manner, the selection unit 31 groups the nth predetermined number of target wireless markers M in order as the nth positioning group.

[0071] For example, it is assumed that the selection unit 31 has selected, in order from the largest elevation angle, wireless markers M2, M3, M6, M7, M1, M4, M5, M8, M10, M11, M9, M12, M14, M15, M13, and M16 as wireless markers M to be used. Note that the selection unit 31 has excluded wireless markers M17 to M20 from the wireless markers M to be used.

[0072] In this case, the selection unit 31 groups the wireless markers M2, M3, M6, and M7 as a first positioning group, and groups the wireless markers M1, M4, M5, and M8 as a second positioning group. The selection unit 31 groups the wireless markers M10, M11, M9, and M12 as a third positioning group, and groups the wireless markers M14, M15, M13, and M16 as a fourth positioning group.

[0073] The selection unit 31 stores in the storage unit 27 the identification information of the wireless marker M to be used in association with the identification information of the positioning group including the wireless marker M to be used.

[0074] The measurement instruction unit 33 judges whether or not it is time to measure the position of the moving body 10. When it is judged that the measurement timing has been reached, the measurement instruction unit 33 instructs the wireless marker M to be used to measure the distance to the moving body 10 by using a request message.

[0075] Specifically, the measurement instruction unit 33 transmits a request message to each of a predetermined number of target wireless markers M included in a specific positioning group via the wireless transmission unit 21 to measure the distance to the moving object 10.

[0076] In this embodiment, the measurement timing for measuring the position of the moving body 10 is the timing at which the moving body 10 can change its moving direction in response to an operation instruction from the moving body control device 20 at each of points P1 to P4 on the travel route 5.

[0077] When the setting unit 29 sets the error range, the measurement instruction unit 33 selects a measurement method to be used when the target wireless marker M measures the distance to the moving object 10 based on the size of the error range. Specifically, the measurement instruction unit 33 selects one of distance measurement conforming to IEEE802.11az and distance measurement conforming to IEEE802.11bf based on the size of the error range. The measurement instruction unit 33 instructs the target wireless marker M of the selected measurement method before the first measurement timing arrives.

[0078] In this embodiment, when the error range is 1 m or more, the measurement instructing unit 33 instructs the wireless marker M to use distance measurement conforming to IEEE802.11az when measuring the distance between the wireless marker M to be used and the moving body 10. When the error range is less than 1 m, the measurement instructing unit 33 instructs the wireless marker M to use distance measurement conforming to IEEE802.11bf when measuring the distance between the wireless marker M to be used and the moving body 10.

[0079] The position calculation unit 35 acquires distance information including the distance between the wireless marker M to be used and the moving body 10 from each of a predetermined number of wireless markers M to be used that are included in a specific positioning group via the wireless receiving unit 23. The position calculation unit 35 calculates (estimates) the position of the moving body 10 based on the acquired distance information of the predetermined number of items. The position calculation unit 35 stores the calculated (estimated) position of the moving body 10 in the storage unit 27. The position of the moving body 10 calculated (estimated) by the position calculation unit 35 is also referred to as the position of the moving body 10 in the specific positioning group.

[0080] When distance measurement conforming to IEEE802.11az is used, the wireless marker M to be used measures the distance to the moving body 10 by referring to the time information of the moving body 10, as described below. In this embodiment, the time of the wireless marker M to be used can be considered to be synchronized with the time of other wireless markers M to be used, due to a synchronization signal periodically transmitted from the moving body control device 20. However, the time of the wireless marker M to be used may not be synchronized with the time of the moving body 10. For this reason, when distance measurement conforming to IEEE802.11az is used, the position calculation unit 35 needs at least four equations to solve four unknowns, namely, the position (x, y, z) of the moving body 10 and the distance error s due to the clock error of the moving body 10, when calculating (estimating) the position of the moving body 10.

[0081] Here, if it is assumed that the distance ri acquired from the target wireless marker M included in a specific positioning group is the sum of the true value of the distance and the distance error s due to the clock error of the moving body 10, the following equation is established. Note that the position of the target wireless marker M is (xMi, yMi, zMi), which is stored in advance in the storage unit 27. ri={(xMi-x) 2 +(yMi-y) 2 +(zMi-z) 2} 1 / 2 +s

[0082] In this embodiment, the predetermined number is set to 4, so the position calculation unit 35 associates the above equation with each of the four target wireless markers M included in the specific positioning group. The position calculation unit 35 substitutes the position of the corresponding target wireless marker M and the distance acquired from the corresponding target wireless marker M into each equation, and solves for the four unknowns x, y, z, and s. In this way, the position calculation unit 35 can calculate (estimate) the position (x, y, z) of the moving body 10.

[0083] In addition, when the specified number is set to 5 or more and five or more wireless markers M to be used are included in a specific positioning group, the position calculation unit 35 uses the least squares method to calculate the optimal solution for the four unknowns x, y, z, and s from five or more equations.

[0084] On the other hand, when distance measurement conforming to IEEE802.11bf is used, the wireless marker M to be used measures the distance to the moving body 10 without referring to the time information of the moving body 10, as described below. For this reason, when distance measurement conforming to IEEE802.11bf is used, the position calculation unit 35 needs at least three equations to solve the three unknowns (x, y, z) that are the position of the moving body 10 when calculating (estimating) the position of the moving body 10.

[0085] Here, the following equation is established for the distance ri acquired from the target wireless marker M included in a specific positioning group. Note that the position of the target wireless marker M is (xMi, yMi, zMi) and is stored in advance in the storage unit 27. ri={(xMi-x) 2 +(yMi-y) 2 +(zMi-z) 2} 1 / 2

[0086] In this embodiment, the predetermined number is set to 4, and therefore the position calculation unit 35 associates the above equation with each of the four target wireless markers M included in the specific positioning group. The position calculation unit 35 substitutes the position of the corresponding target wireless marker M and the distance acquired from the corresponding target wireless marker M into each equation, and calculates the optimization of the three unknowns x, y, and z from the four equations using the least squares method. This allows the position calculation unit 35 to calculate (estimate) the position (x, y, z) of the moving body 10.

[0087] The determination unit 37 performs position determination of the moving body 10. Specifically, the determination unit 37 sequentially determines whether or not an error between the position of the moving body 10 in the first positioning group and the position of the moving body 10 in a positioning group other than the first positioning group is included within the error range set by the setting unit 29. If the error is included within the error range, the determination unit 37 determines the position of the moving body 10 in the first positioning group as the current position of the moving body 10, and stores it in the storage unit 27.

[0088] When the error between the position of the moving body 10 in the first positioning group and the current positioning group is not included within the error range for all positioning groups other than the first positioning group, the determination unit 37 causes the position calculation unit 35 to calculate (estimate) the position of the moving body 10 based on the distance information acquired from all of the intended wireless markers M. The determination unit 37 determines the position of the moving body 10 calculated (estimated) based on the distance information acquired from all of the intended wireless markers M as the current position of the moving body 10 and stores it in the memory unit 27.

[0089] The matching execution unit 39 calculates the moving speed, moving direction, etc. of the moving body 10 based on the current position of the moving body 10 determined by the determination unit 37, the map information on the travel route 5 set by the setting unit 29, and the moving speed of the moving body 10 included in the operation instruction at the previous measurement timing. In this case, the matching execution unit 39 may use the current moving speed of the moving body 10 separately acquired by the moving body control device 20 instead of the speed information of the moving body 10 included in the operation instruction at the previous measurement timing.

[0090] The matching execution unit 39 compares the position of one of points P1 to P4 on the driving route 5 on the map data within the factory 3 where the moving body 10 should be located at the current measurement timing with the current position of the moving body 10 determined by the judgment unit 37.

[0091] When the current position of the moving body 10 is deviated from the position of the one point, the matching execution unit 39 calculates the moving speed, moving direction, etc. of the moving body 10 so that the moving body 10 is located within a predetermined error range centered on the one point. In addition, the matching execution unit 39 calculates the moving speed, moving direction, etc. of the moving body 10 so that the moving body 10 changes its moving direction at the one point and moves to the next point among the points P1 to P on the travel route 5.

[0092] In addition, when the moving body 10 stops at each measurement timing, the matching execution unit 39 may calculate the moving speed and moving direction of the moving body 10 based only on the current position of the moving body 10 and map information regarding the travel route 5.

[0093] The instruction unit 41 generates an operation instruction including the moving speed, moving direction, etc. of the moving body 10 calculated by the matching execution unit 39. The instruction unit 41 transmits the generated operation instruction to the moving body 10 via the wireless transmission unit 21 and one or more wireless markers M including the wireless marker M1. As a result, the instruction unit 41 causes the moving body 10 to automatically travel along the travel route 5.

[0094] Here, there are multiple communication paths from the mobile object control device 20 to the mobile object 10, but the instruction unit 41 selects a communication path with a good radio wave environment from among the multiple communication paths and transmits an operation instruction.

[0095] [Wireless marker configuration] Next, a description will be given of the configuration of the wireless marker M. Fig. 4 is a block diagram showing an example of the functional configuration of the wireless marker M according to this embodiment. As shown in Fig. 4, the wireless marker M includes a wireless transmitting unit 51, a wireless receiving unit 53, a control unit 55, a storage unit 57, a time unit 59, a generating unit 61, a changing unit 63, a switching unit 65, a measuring unit 67, an FTM executing unit 69, and a sensing executing unit 71.

[0096] The wireless transmission unit 51 transmits a wireless signal to an adjacent wireless marker M. When the wireless marker M is the wireless marker M1, the wireless transmission unit 51 transmits a wireless signal to the mobile object control device 20. When the wireless marker M is any of the wireless markers M2 to M20, the wireless marker M transmits a wireless signal to the mobile object control device 20 via one or more other wireless markers M including the wireless marker M1. The wireless signal is, for example, distance information.

[0097] The wireless receiving unit 53 receives a wireless signal from an adjacent wireless marker M. When the wireless marker M is the wireless marker M1, the wireless receiving unit 53 receives a wireless signal from the moving object control device 20. When the wireless marker M is any of the wireless markers M2 to M20, the wireless marker M receives a wireless signal from the moving object control device 20 via one or more other wireless markers M including the wireless marker M1. The wireless signal is, for example, a synchronization signal, a request message, or an operation instruction for the moving object 10.

[0098] The wireless transmission unit 51 and the wireless transmission unit 51 may be disposed at different positions to improve sensing accuracy in distance measurement conforming to IEEE802.11bf performed by a sensing execution unit 71 described later. The wireless transmission unit 51 and the wireless transmission unit 51 are also simply referred to as a transmission unit and a reception unit, respectively.

[0099] The control unit 55 controls the entire processing in the wireless marker M. Specifically, the control unit 55 controls the operation of each of the wireless transmission unit 51, the wireless reception unit 53, the storage unit 57, the time unit 59, the generation unit 61, the change unit 63, the switching unit 65, the measurement unit 67, the FTM execution unit 69, and the sensing execution unit 71.

[0100] The storage unit 57 pre-stores control parameters necessary for wireless communication, position information of the wireless markers M1-M20 including the own device, addresses of the wireless markers M1-M20 including the own device, identification information of the wireless markers M1-M20 including the own device, the address of the moving body 10, and the address of the moving body control device 20. The storage unit 57 stores the distance between the wireless marker M and the moving body 10 acquired by the measurement unit 67.

[0101] The time unit 59 generates the time of its own device. The time unit 59 periodically receives a synchronization signal from the mobile object control device 20 via the wireless receiving unit 53. When the time unit 59 receives the synchronization signal, it synchronizes the time of its own device with the synchronization signal.

[0102] The generating unit 61 generates communication data to be relayed by one or more other wireless markers M. When generating the communication data, the generating unit 61 sets a frame of the communication data. Fig. 6 is a diagram for explaining the frame structure of the communication data. As shown in Fig. 6, the frame of the communication data is composed of a preamble field, a header field, a data field, and an FCS (Frame Check Sequence) field.

[0103] The preamble field contains a specific sequence of bits that the receiver uses to synchronize with the frame. The header fields contain the primary destination address, primary source address, secondary destination address, and secondary source address.

[0104] In this embodiment, two devices corresponding to the start point and the end point of the communication path of the communication data are called the first source device and the first destination device, respectively. In addition, among two devices that can directly communicate with each other on the communication path of the communication data, the device corresponding to the source of the communication data is called the second source device, and the device corresponding to the destination of the communication data is called the second destination device.

[0105] The primary destination address in the header field is set to the address of the primary destination device. The primary source address in the header field is set to the address of the primary source device. The secondary destination address in the header field is set to the address of the secondary destination device. The secondary source address in the header field is set to the address of the secondary source device.

[0106] The data field contains the data to be transmitted, and the FCS field contains a bit string that the receiver uses to determine whether the frame is error-free.

[0107] For example, when the wireless marker M transmits distance information including the distance to the mobile body 10 to the mobile body control device 20, the generation unit 61 sets the distance information in the data field of the communication data. In this case, the generation unit 61 sets the address of the mobile body control device 20 and the address of the own device in the first destination address and the first source address, respectively. The generation unit 61 sets the address of another wireless marker M adjacent to the own device on the mobile body control device 20 side and the address of the own device in the second destination address and the second source address, respectively.

[0108] The distance information includes the distance between the wireless marker M and the moving object 10 and the identification information of the wireless marker M.

[0109] The above-mentioned frame structure is also applied to the communication data that the mobile object control device 20 transmits to the wireless marker M.

[0110] For example, when the mobile object control device 20 transmits a request message to the wireless marker M, it sets the request message in the data field of the communication data. In this case, the mobile object control device 20 sets the address of the wireless marker M and the address of its own device in the first destination address and the first source address, respectively. The mobile object control device 20 sets the address of the wireless marker M1 and the address of its own device in the second destination address and the second source address, respectively.

[0111] Furthermore, when the mobile object control device 20 transmits an operation instruction to the mobile object 10, it sets the operation instruction in the data field of the communication data. In this case, the address of the wireless marker M that transmits the operation instruction to the mobile object 10 and the address of the own device are set in the first destination address and the first source address, respectively. The generation unit 61 sets the address of the wireless marker M1 and the address of the own device in the second destination address and the second source address, respectively.

[0112] The operation instruction includes the moving speed and moving direction of the moving object 10, etc.

[0113] When the wireless marker M relays communication data, the change unit 63 changes the frame setting of the communication data received via the wireless receiving unit 53. Specifically, the change unit 63 determines whether or not the address of the own device is not set in the first destination address in the header field of the communication data and the address of the own device is set in the second destination address.

[0114] When the address of the own device is not set in the first destination address and the address of the own device is set in the second destination address, the change unit 63 checks which of the two adjacent other wireless markers M is set in the second source address.

[0115] When the address of one of the two adjacent other wireless markers M is set as the second source address, the change unit 63 changes the second destination address from the address of the own device to the address of the other of the two adjacent other wireless markers M. The change unit 63 changes the second source address from the address of one of the two adjacent other wireless markers M to the address of the own device.

[0116] When the change unit 63 changes the frame setting of the communication data, it transmits the communication data via the wireless transmission unit 51. This enables the wireless marker M to relay the communication data.

[0117] When the address of the own device is set in the first destination address of the header field of the communication data, the change unit 63 determines that the communication data is addressed to the own device and reads the data field of the communication data. When a request message is set in the data field of the communication data, the control unit 55 starts the measurement unit 67. When an operation instruction is set in the data field of the communication data, the control unit 55 transmits the operation instruction to the mobile unit 10 via the wireless transmission unit 51.

[0118] The switching unit 65 switches between an FTM execution unit 69 that executes distance measurement conforming to IEEE802.11az and a sensing execution unit 71 that executes distance measurement conforming to IEEE802.11bf based on an instruction from the mobile object control device 20. Specifically, the switching unit 65 starts the FTM execution unit 69 and stops the sensing execution unit 71 in order to switch to distance measurement conforming to IEEE802.11az based on an instruction from the mobile object control device 20. On the other hand, the switching unit 65 starts the sensing execution unit 71 and stops the FTM execution unit 69 in order to switch to distance measurement conforming to IEEE802.11bf based on an instruction from the mobile object control device 20.

[0119] In a state in which the switching unit 65 activates the FTM execution unit 69 and stops the sensing execution unit 71, the measurement unit 67 executes distance measurement conforming to IEEE802.11az using the FTM execution unit 69 based on a request message from the mobile object control device 20. The measurement unit 67 acquires the distance between the wireless marker M and the mobile object 10 calculated by the FTM execution unit 69.

[0120] On the other hand, in a state in which the switching unit 65 activates the sensing execution unit 71 and stops the FTM execution unit 69, the measurement unit 67 uses the sensing execution unit 71 to perform distance measurement in accordance with IEEE802.11bf based on a request message from the mobile object control device 20. The measurement unit 67 acquires the distance between the wireless marker M and the mobile object 10 calculated by the sensing execution unit 71.

[0121] The FTM execution unit 69 executes distance measurement conforming to IEEE802.11az. Specifically, the FTM execution unit 69 measures the distance between the wireless marker M and the moving object 10 based on the FTM protocol. In response to an instruction from the measurement unit 67, the FTM execution unit 69 transmits a measurement frame conforming to IEEE802.11az to the moving object 10 via the wireless transmission unit 51. When transmitting the measurement frame conforming to IEEE802.11az, the FTM execution unit 69 temporarily stores the transmission time of the measurement frame in the storage unit 57.

[0122] The FTM execution unit 69 transmits a measurement frame conforming to IEEE802.11az to the mobile unit 10 via the wireless transmission unit 51, and then receives a report frame conforming to IEEE802.11az from the mobile unit 10 via the wireless reception unit 53, and reads the reception time of the measurement frame from the report frame.

[0123] When the FTM execution unit 69 reads the reception time of the measurement frame, it calculates the difference between the transmission time of the measurement frame temporarily stored in the storage unit 57 and the reception time of the read measurement frame.

[0124] Here, the calculated difference between the transmission time and reception time of the measurement frame represents the time it takes for the radio waves used to transmit the measurement frame to reach the moving body 10 from the wireless marker M. The FTM execution unit 69 multiplies the calculated difference between the transmission time and reception time of the measurement frame by the speed of radio waves (light) to calculate the distance between the wireless marker M and the moving body 10.

[0125] In addition, when the mobile body 10 is configured to include the transmission time of the report frame in the report frame and transmit it to the wireless marker M, the FTM execution unit 69 temporarily stores the reception time of the report frame in the memory unit 57 instead of the transmission time of the measurement frame.

[0126] In this case, when the FTM execution unit 69 receives a reporting frame from the mobile object 10, it reads the transmission time of the reporting frame from the reporting frame. When the FTM execution unit 69 reads the transmission time of the reporting frame, it calculates the difference between the read transmission time of the reporting frame and the reception time of the reporting frame temporarily stored in the storage unit 57.

[0127] Here, the calculated difference between the transmission time and reception time of the report frame represents the time it takes for the radio waves used to transmit the report frame to reach the wireless marker M from the moving body 10. The FTM execution unit 69 multiplies the calculated difference between the transmission time and reception time of the report frame by the speed of radio waves (light) to calculate the distance between the wireless marker M and the moving body 10.

[0128] Since IEEE802.11az is one of the standards for WLAN, ranging conforming to IEEE802.11az is also called ranging using WLAN frames. Furthermore, ranging conforming to IEEE802.11az is also called ranging based on time of arrival (ToA), since ranging is based on the time when the moving object 10 receives a measurement frame or the time when the wireless marker M receives a report frame.

[0129] The sensing execution unit 71 executes distance measurement conforming to IEEE802.11bf. Specifically, the sensing execution unit 71 measures the distance between the wireless marker M and the moving object 10 based on WLAN sensing. The sensing execution unit 71 emits radio waves from the wireless transmission unit 51 in response to an instruction from the measurement unit 67.

[0130] After emitting radio waves from the wireless transmitting unit 51, the sensing executing unit 71 receives, at the wireless receiving unit 53, a composite wave of the radio waves (direct waves) emitted from the wireless transmitting unit 51 and the radio waves (delayed waves) reflected by the moving body 10 or the like. The sensing executing unit 71 measures channel state information (CSI) based on the composite wave of the radio waves received by the wireless receiving unit 53, and calculates the distance between the wireless marker M and the moving body 10.

[0131] Here, the principle of WLAN sensing used in IEEE802.11bf will be described. In IEEE802.11bf, OFDM (Orthogonal Frequency Division Multiplexing) transmission is adopted. OFDM is composed of multiple subcarriers according to the bandwidth. When radio waves are emitted from the radio transmitter 51 of the wireless marker M using multiple subcarriers, the composite wave of the radio waves at the radio receiver 53 differs for each frequency according to the delay time until the radio waves reach the radio receiver 53 by the moving object 10. Therefore, in the frequency domain, a frequency spectrum according to the delay time is obtained. This frequency spectrum is channel state information that represents the multipath propagation state.

[0132] Therefore, the sensing execution unit 71 can measure channel state information based on the composite wave of the radio waves received by the wireless receiving unit 53, and obtain the delay time caused by the moving body 10 by comparing the measured channel state information with the frequency spectrum corresponding to each delay time pre-stored in the storage unit 57. The sensing execution unit 71 calculates the distance between the wireless marker M and the moving body 10 based on the obtained delay time.

[0133] The sensing execution unit 71 performs ranging in accordance with IEEE802.11bf using a frequency in the range of 1 GHz or more and 7.125 GHz or less. Since IEEE802.11bf is one of the standards for WLAN, ranging in accordance with IEEE802.11bf is also called ranging using WLAN sensing.

[0134] [Wireless marker hardware configuration] Next, a description will be given of a hardware configuration of the wireless marker M. FIG.

[0135] As shown in FIG. 5, the wireless marker M includes a CPU (Central Processing Unit) 101, a ROM (Read Only Memory) 103, a RAM (Random Access Memory) 105, a storage 107, an antenna 109, a transmission / reception circuit 111, an RTC 113, and an interface 115.

[0136] The CPU 101 executes a program stored in the ROM 103. The CPU 101 performs calculations on data loaded into the RAM 105 in accordance with the program, and comprehensively controls each part of the wireless marker M. The CPU is also called a processor.

[0137] The ROM 103 stores programs and the like executed by the CPU 101. In this embodiment, the ROM 103 stores at least a program for controlling distance measurement conforming to IEEE802.11az and distance measurement conforming to IEEE802.11bf. The RAM 105 temporarily holds calculation data when the CPU 101 executes the programs stored in the ROM 103. The ROM and RAM are also referred to as non-volatile memory and volatile memory, respectively.

[0138] The storage 107 stores the information stored in the above-mentioned storage unit 57. The CPU 101 controls reading and writing of data from and to the storage 107 in accordance with a program stored in the ROM 103. The storage 107 is, for example, a hard disk drive (HDD) or a solid state drive (SSD), and the storage 107 may be a combination of an HDD and an SSD.

[0139] The antenna 109 emits radio waves under the control of the CPU 101. The transmission / reception circuit 111 performs various processes for wireless communication under the control of the CPU 101. The RTC 113 generates the time of the wireless marker M based on an internal clock. The interface 115 is connected to an external device (not shown) wirelessly or by wire.

[0140] Similarly, the mobile object control device 20 also has a hardware configuration as shown in Fig. 5. In this case, the ROM stores at least a program for controlling a procedure for selecting the wireless marker M and a procedure for controlling the mobile object 10, which will be described later. In addition, the storage stores the information stored in the storage unit 27 described above.

[0141] [Procedure for selecting wireless markers] Next, the procedure for selecting a wireless marker will be described. Fig. 7 is a diagram showing an example of a flowchart of the procedure for selecting a wireless marker. The procedure for selecting a wireless marker is a procedure for selecting a wireless marker M to be used from the wireless markers M1 to M20 based on the magnitude of the elevation angle of the wireless markers M1 to M20 at the points P1 to P4 of the travel route 5, and determining the order of positioning.

[0142] 7, in the mobile object control device 20, the setting unit 29 sets a travel route 5 on map data within the factory 3 previously stored in the storage unit 27, and causes the storage unit 27 to store map information regarding the travel route 5 (step S1). When the travel route 5 is set, the selection unit 31 excludes wireless markers M that are hidden by shadows from the travel route 5 by an operation of the worker from wireless markers M to be used. In this embodiment, it is assumed that there are no wireless markers M that are hidden by shadows from the travel route 5.

[0143] The selection unit 31 calculates the elevation angles of the wireless markers M1 to M20 at the points P1 to P4 on the travel route 5 (step S3). Fig. 8 is a diagram for explaining the calculation of the elevation angle of the wireless marker M. Note that in Fig. 8, the wireless markers M9 to M20 are omitted from the illustration.

[0144] The selection unit 31 reads out the position information (xP1, yP1, zP1) of the point P1 on the travel route 5 and the position information (xMi, yMi, zMi) of the wireless marker Mi from the storage unit 27. Note that the subscript i takes a value from 1 to 20.

[0145] The selection unit 31 calculates the elevation angle of the wireless marker Mi at the point P1 using position information (xP1, yP1, zP1) of the point P1 and position information (xMi, yMi, zMi) of the wireless marker Mi. This allows the selection unit 31 to calculate the elevation angles of the wireless markers M1 to M20 at the point P1.

[0146] Similarly, the selection unit 31 calculates the elevation angles of the wireless markers M1 to M20 at the point P2, the elevation angles of the wireless markers M1 to M20 at the point P3, and the elevation angles of the wireless markers M1 to M20 at the point P4. As shown in Fig. 8, the points P2, P3, and P4 have position information (xP2, yP2, zP2), (xP3, yP3, zP3), and (xP4, yP4, zP4), respectively.

[0147] In this embodiment, the angles of elevation of the wireless markers M1 to M20 at the points P1 to P4 on the travel route 5 are regarded as angles of elevation of the wireless markers M1 to M20 as seen from the moving object 10 at the points P1 to P4.

[0148] After calculating the elevation angles of the wireless markers M1 to M20 at the points P1 to P4 on the travel route 5, the selection unit 31 selects a wireless marker M to be used from the wireless markers M1 to M20 and determines the positioning order of the wireless markers M to be used (step S5).

[0149] First, the selection unit 31 selects a wireless marker M to be used from among the wireless markers M1 to M20 based on the magnitude of the elevation angle of the wireless markers M1 to M20 at the points P1 to P4 on the travel route 5. Specifically, the selection unit 31 selects the largest elevation angle of each wireless marker M from among the elevation angles at the points P1 to P4 on the travel route 5. The selection unit 31 excludes, from among the wireless markers M1 to M20, wireless markers M having an elevation angle equal to or smaller than a threshold value from the wireless markers M to be used. The selection unit 31 selects, from among the wireless markers M1 to M20, a wireless marker M having a value larger than the threshold value as the wireless marker M to be used.

[0150] When all of the wireless markers M1 to M20 have elevation angles equal to or smaller than the threshold value, the four wireless markers M having the largest elevation angles are selected from the wireless markers M1 to M20 as the wireless markers M to be used.

[0151] In this embodiment, the selection unit 31 selects the wireless markers M1 to M16 as the wireless markers M to be used.

[0152] Next, the selection unit 31 arranges the wireless markers M1 to M16 selected as the wireless markers M to be used in order of increasing elevation angle, and determines the order in which the positions of the wireless markers M to be used are to be measured.

[0153] Fig. 9 is a diagram for explaining the determination of the order of wireless markers M. Note that wireless markers M9 to M20 are omitted from Fig. 9. In the example shown in Fig. 9, the selection unit 31 compares the elevation angle θ (P1-M2) of the wireless marker M2 at point P1 with the elevation angle θ (P1-M8) of the wireless marker M8 at point P1. In this case, since the elevation angle θ (P1-M2) is greater than the elevation angle θ (P1-M8), the positioning order of the markers M to be used is, as far as point P1 is concerned, the wireless markers M2, M8.

[0154] In this embodiment, when comparing the elevation angles of two wireless markers M at the points P1 to P4 on the travel route 5, the selection unit 31 selects the largest elevation angle among the elevation angles at the points P1 to P4 on the travel route 5 for each wireless marker M. The selection unit 31 assigns a higher rank to the wireless marker M having the larger selected elevation angle among the two wireless markers M.

[0155] If the two selected elevation angles are the same, the wireless marker M having the smaller number assigned as the identification information to the two wireless markers M is given a higher ranking.

[0156] In this embodiment, the selection unit 31 determines the positioning order of the wireless markers M to be used in the following order: wireless markers M2, M3, M6, M7, M1, M4, M5, M8, M10, M11, M9, M12, M14, M15, M13, and M16.

[0157] When the selection unit 31 determines the positioning order of the wireless markers M to be used, the selection unit 31 groups the wireless markers M to be used into a plurality of positioning groups in descending order of positioning order, for each predetermined number of wireless markers M to be used. In this embodiment, the predetermined number is set to 4.

[0158] In this embodiment, the selection unit 31 groups the wireless markers M2, M3, M6, and M7 into a first positioning group, and groups the wireless markers M1, M4, M5, and M8 into a second positioning group. The selection unit 31 groups the wireless markers M10, M11, M9, and M12 into a third positioning group, and groups the wireless markers M14, M15, M13, and M16 into a fourth positioning group.

[0159] According to the above-mentioned selection procedure, the wireless marker M with a small elevation angle is not used as the target wireless marker M, so that the influence of multipath and the like can be eliminated and the positioning accuracy can be improved. Moreover, since the above-mentioned selection procedure is performed by the mobile object control device 20, no processing load is imposed on the wireless marker M and the mobile object 10, and the selection procedure can be easily performed.

[0160] [Control procedure for moving objects] Next, a control procedure for the moving body 10 will be described. Fig. 10 is a diagram showing an example of a flowchart of the control procedure for the moving body according to this embodiment. The control procedure for the moving body 10 is a control procedure for automatically traveling the moving body 10 along the travel route 5.

[0161] 10, in the moving body control device 20, the measurement instruction unit 33 judges whether or not it is time to measure the position of the moving body 10 (step S11). If the measurement instruction unit 33 judges that it is not time to measure the position of the moving body 10, the process returns to step S11 again, and makes the same judgment after a predetermined time has elapsed.

[0162] When the measurement instruction unit 33 determines that the measurement timing has been reached, it transmits a request message to each of the predetermined number of wireless markers M to be used that are included in the first positioning group via the wireless transmission unit 21 to request that they measure the distance to the moving object 10 (step S13). In this embodiment, the measurement instruction unit 33 transmits the request message via the wireless transmission unit 21 to each of the wireless markers M2, M3, M6, and M7 that are included in the first positioning group.

[0163] The position calculation unit 35 acquires distance information including the distance between the wireless marker M to be used and the moving body 10 from each of a predetermined number of wireless markers M to be used that are included in the first positioning group via the wireless receiving unit 23. The position calculation unit 35 calculates (estimates) the position of the moving body 10 based on the acquired distance information of the predetermined number of items (step S15). In this embodiment, the position calculation unit 35 acquires distance information from each of the wireless markers M2, M3, M6, and M7 that are included in the first positioning group via the wireless transmitting unit 21, and calculates (estimates) the position of the moving body 10.

[0164] When the position calculation unit 35 calculates (estimates) the position of the moving body 10, the measurement instruction unit 33 transmits a request message to each of the predetermined number of wireless markers M to be used that are included in the next positioning group via the wireless transmission unit 21 to request that the markers measure the distance to the moving body 10 (step S17). In this embodiment, the measurement instruction unit 33 transmits a request message via the wireless transmission unit 21 to each of the wireless markers M1, M4, M5, and M8 that are included in the second positioning group.

[0165] The position calculation unit 35 acquires distance information including the distance between the wireless marker M to be used and the moving body 10 from each of a predetermined number of wireless markers M to be used that are included in the second positioning group via the wireless receiving unit 23. The position calculation unit 35 calculates (estimates) the position of the moving body 10 based on the acquired distance information of the predetermined number of items (step S19). In this embodiment, the position calculation unit 35 acquires distance information from each of the wireless markers M1, M4, M5, and M8 that are included in the second positioning group via the wireless transmitting unit 21, and calculates (estimates) the position of the moving body 10.

[0166] When the position calculation unit 35 calculates (estimates) the position of the moving body 10, the determination unit 37 determines whether or not the error between the position of the moving body 10 in the first positioning group and the position of the moving body 10 in the second positioning group is included within the error range set by the setting unit 29 (step S21). When the determination unit 37 determines that the error is included within the error range, it determines the position of the moving body 10 in the first positioning group as the current position of the moving body 10, and proceeds to step S27.

[0167] When the determination unit 37 determines that the error is not within the error range, the measurement instruction unit 33 transmits a request message to each of the predetermined number of target wireless markers M included in the next positioning group via the wireless transmission unit 21 to measure the distance to the moving object 10 (step S23). In this embodiment, the measurement instruction unit 33 transmits a request message via the wireless transmission unit 21 to each of the wireless markers M10, M11, M9, and M12 included in the third positioning group, or each of the wireless markers M14, M15, M13, and M16 included in the fourth positioning group.

[0168] The position calculation unit 35 acquires distance information including the distance between the wireless marker M to be used and the moving body 10 from each of the predetermined number of wireless markers M to be used that are included in the next positioning group via the wireless receiving unit 23. The position calculation unit 35 calculates (estimates) the position of the moving body 10 based on the acquired distance information of the predetermined number of items (step S25). In this embodiment, the position calculation unit 35 acquires distance information from each of the wireless markers M10, M11, M9, and M12 that are included in the third positioning group or each of the wireless markers M14, M15, M13, and M16 that are included in the fourth positioning group via the wireless transmitting unit 21, and calculates (estimates) the position of the moving body 10.

[0169] When the position calculation unit 35 calculates (estimates) the position of the moving body 10, the determination unit 37 determines whether or not the error between the position of the moving body 10 in the first positioning group and the position of the moving body 10 in the next positioning group is within the error range set by the setting unit 29 (step S21). If the determination unit 37 determines that the error is within the error range, the position of the moving body 10 in the first positioning group is determined to be the current position of the moving body 10, and the process proceeds to step S27. If the determination unit 37 determines that the error is not within the error range, the process proceeds to step S23.

[0170] If the error between the position of the moving body 10 in the first positioning group and the current positioning group is not within the error range for all positioning groups other than the first positioning group, the determination unit 37 causes the position calculation unit 35 to calculate (estimate) the position of the moving body 10 based on the distance information acquired from all of the intended wireless markers M. The determination unit 37 determines the position of the moving body 10 calculated (estimated) based on the distance information acquired from all of the intended wireless markers M as the current position of the moving body 10, and proceeds to step S27.

[0171] When the determination unit 37 determines the current position of the moving object 10, the matching execution unit 39 executes a map matching process, which will be described later (step S27).

[0172] When the matching executing unit 39 executes the map matching process, the instruction unit 41 generates an operation instruction including the moving speed, moving direction, etc. of the moving body 10 calculated by the matching executing unit 39. The instruction unit 41 transmits the generated operation instruction to the moving body 10 via the wireless transmitting unit 21 and one or more wireless markers M including the wireless marker M1 (step S29). As a result, the instruction unit 41 causes the moving body 10 to automatically travel along the travel route 5.

[0173] [Distance measurement processing] Next, the distance measurement process will be described. The distance measurement process is a process executed between steps S13 and S15, between steps S17 and S19, and between steps S23 and S25 in the control procedure of the moving body 10. Fig. 11 is a diagram showing an example of the sequence of the distance measurement process.

[0174] Figure 11 shows a sequence in which, between steps S13 and S15 of the control procedure for the mobile body 10, the measurement instruction unit 33 in the mobile body control device 20 sends a request message to a wireless marker M2 included in the first positioning group, and the position calculation unit 35 acquires distance information from the wireless marker M2.

[0175] As shown in FIG. 11, in the mobile object control device 20, when the measurement instructing unit 33 determines the first positioning group as the positioning group for transmitting a request message (step S51), communication data including the request message is generated.

[0176] In this case, a request message is set in the data field of the communication data. The address of the wireless marker M2 and the address of the mobile object control device 20 are set in the first destination address and the first source address of the header field of the communication data, respectively. The address of the wireless marker M1 and the address of the mobile object control device 20 are set in the second destination address and the second source address of the header field of the communication data, respectively.

[0177] When the measurement instruction unit 33 generates the communication data including the request message, the measurement instruction unit 33 transmits the communication data to the wireless marker M1 via the wireless transmission unit 21 (step S53).

[0178] In the wireless marker M1, when the change unit 63 receives communication data via the wireless receiving unit 53, it sets the second destination address and the second source address in the header field of the communication data to the address of the wireless marker M2 and the address of the wireless marker M1, respectively (step S55).

[0179] After changing the second destination address and the second source address in the header field of the communication data, the change unit 63 transmits the communication data to the wireless marker M2 via the wireless transmission unit 51 (step S57).

[0180] In the wireless marker M2, when the measurement unit 67 receives the communication data including the request message via the wireless receiving unit 53, it executes distance measurement conforming to IEEE802.11az or distance measurement conforming to IEEE802.11bf using the FTM execution unit 69 or the sensing execution unit 71 based on the request message (step S59). The measurement unit 67 acquires the distance between the wireless marker M2 and the moving object 10 calculated by the FTM execution unit 69 or the sensing execution unit 71.

[0181] When the measurement unit 67 acquires the distance, the generation unit 61 generates communication data including distance information including the distance. In this case, the distance information is set in the data field of the communication data. The address of the mobile object control device 20 and the address of the wireless marker M2 are set in the first destination address and the first source address in the header field of the communication data, respectively. The address of the wireless marker M1 and the address of the wireless marker M2 are set in the second destination address and the second source address in the header field of the communication data, respectively.

[0182] When the generation unit 61 generates the communication data including the distance information, the generation unit 61 transmits the communication data to the wireless marker M1 via the wireless transmission unit 21 (step S61).

[0183] In the wireless marker M1, when the change unit 63 receives communication data via the wireless receiving unit 53, it sets the second destination address and the second source address in the header field of the communication data to the address of the mobile control device 20 and the address of the wireless marker M1, respectively (step S63).

[0184] After changing the second destination address and the second source address in the header field of the communication data, the change unit 63 transmits the communication data to the mobile object control device 20 via the wireless transmission unit 51 (step S65).

[0185] When the position calculation unit 35 receives communication data including distance information including distance via the wireless receiving unit 23, it calculates (estimates) the position of the moving body 10 based on the distance information received from the wireless marker M2 and the distance information received from the other wireless markers M3, M6, and M7 (step S67).

[0186] [Map matching process] Next, a description will be given of the map matching process, which is executed in S27 of the control procedure of the moving object 10. Fig. 12 is a diagram showing an example of a flowchart of the map matching process.

[0187] 12, in the mobile object control device 20, the matching execution unit 39 acquires map information of the travel route 5 from the storage unit 27 (step S81). The matching execution unit 39 compares the position of one of the points P1 to P4 of the travel route 5 on the map data within the factory 3 where the mobile object 10 should be located at the current measurement timing with the current position of the mobile object 10 determined by the determination unit 37 (step S83).

[0188] Based on the comparison, the matching executing unit 39 determines whether or not it is necessary to correct the current position of the moving body 10 (step S85). Specifically, the matching executing unit 39 determines whether or not the current position of the moving body 10 deviates from the position of the one point beyond a predetermined error range.

[0189] If the current position of the moving body 10 deviates from the position of the one point beyond a predetermined error range, the matching execution unit 39 determines that it is necessary to correct the current position of the moving body 10. In this case, the matching execution unit 39 calculates the moving speed, moving direction, etc. of the moving body 10 so that the moving body 10 is located within a predetermined error range centered on the one point, and corrects the position of the moving body 10 (step S89). This ends the process.

[0190] On the other hand, if the current position of the moving body 10 does not deviate from the position of the one point beyond the predetermined error range, the matching executing unit 39 determines that there is no need to correct the current position of the moving body 10. In this case, the matching executing unit 39 ends the process without correcting the position of the moving body 10.

[0191] Fig. 13 is a diagram for explaining map matching. As shown in Fig. 13, when the moving object 10 is present at position Pt0 on the travel route 5 at measurement timing (t=t0) on the map data, it is predicted that the moving object 10 will be present in area Pt1 at the next measurement timing (t=t1) based on the travel speed of the moving object 10 and the travel route 5.

[0192] At the next measurement timing (t=t1), if the moving object 10 is estimated to be in area PE based on positioning including error, area PE1 where area Pt1 and area PE overlap will be the location where the moving object 10 is located.

[0193] [Actions and Effects] According to this embodiment, the mobile object control device 20 is capable of communicating with a plurality of wireless markers M arranged in an area where the mobile object 10 can travel automatically, and includes a setting unit 29, a selection unit 31, a measurement instruction unit 33, an estimation unit, and a travel instruction unit. The setting unit 29 sets map information related to a travel route 5 of the mobile object 10. The selection unit 31 selects a plurality of wireless markers M to be used from the plurality of wireless markers M based on the travel route 5.

[0194] The measurement instruction unit 33 instructs the wireless marker M to be used to measure the distance between the wireless marker M to be used and the moving body 10. The estimation unit acquires distance information including the measured distance from the wireless marker M to be used, and estimates the position of the moving body 10 based on the acquired distance information. The travel instruction unit automatically travels the moving body 10 along the travel route 5 based on the estimated position of the moving body 10 and map information.

[0195] The estimation unit is configured to realize the functions of the position calculation unit 35 and the determination unit 37. The travel instruction unit is configured to realize the functions of the matching execution unit 39 and the instruction unit 41.

[0196] With the above-mentioned configuration, the position of the moving body 10 is measured using a plurality of target wireless markers M, so there is no problem even if some of the wireless markers M1 to M20 are hidden by process equipment due to changes in the process layout. The wireless markers M1 to M20 can be placed above or below an area in which the moving body 10 can travel automatically, and can also be buried in the ground of the area.

[0197] Therefore, even if the process layout is changed, the worker can cause the moving body to travel automatically by simply setting new map information regarding the travel route 5 without having to re-lay out the multiple wireless markers M.

[0198] Therefore, according to the mobile body control device 20 of this embodiment, even when the process layout is changed, the mobile body 10 can be automatically driven without increasing the burden on the worker.

[0199] According to this embodiment, the setting unit 29 sets an error range that is allowable when the estimation unit estimates the position of the moving object 10. The measurement instruction unit 33 selects one of distance measurement using a WLAN frame and distance measurement using WLAN sensing according to the size of the error range, and instructs the wireless marker M to be used to measure the distance using the selected one.

[0200] Here, as described above, distance measurement using a WLAN frame uses the time generated by the moving body 10 to calculate the distance between the target wireless marker M and the moving body 10. Therefore, the accuracy of the calculated distance depends on the accuracy of the RTC 13 of the moving body 10.

[0201] In contrast, as described above, distance measurement using WLAN sensing calculates the distance between the target wireless marker M and the moving object 10 by using the reflection of radio waves emitted from the target wireless marker M. Therefore, the accuracy of the calculated distance does not depend on the accuracy of the RTC 13 of the moving object 10. As a result, distance measurement using WLAN sensing can reduce the error range compared to distance measurement using WLAN frames.

[0202] Therefore, when the error range needs to be reduced, the above-mentioned configuration can easily be used to switch from measuring distance using WLAN frames to measuring distance using WLAN sensing, thereby reducing the burden on the operator.

[0203] According to the present embodiment, a plurality of points P1 to P4 at which distances are measured are set on the travel route 5. The selection unit 31 selects a plurality of wireless markers M to be used from among the plurality of wireless markers M based on the magnitudes of the elevation and depression angles of the plurality of wireless markers M at the plurality of points P1 to P4.

[0204] With the above-described configuration, a plurality of wireless markers M to be used are selected based on the magnitude of the elevation / depression angles of the plurality of wireless markers M at all measurement points on the travel route 5. Therefore, it is not necessary to change the selected wireless markers M to be used until the travel route 5 is changed, which reduces the burden on the worker.

[0205] According to this embodiment, the selection unit 31 selects the largest elevation / depression angle among the elevation / depression angles at the multiple points P1 to P4 for each wireless marker M. The selection unit 31 selects multiple wireless markers M having elevation / depression angles larger than a threshold value as wireless markers M to be used from the multiple wireless markers M. The selection unit 31 groups a predetermined number of wireless markers M to be used in ascending order of elevation / depression angles as a first positioning group, and groups the next predetermined number of wireless markers M to be used as a second positioning group.

[0206] The estimation unit estimates the position of the moving body 10 based on first distance information acquired from a target wireless marker M included in the first positioning group. The estimation unit estimates the position of the moving body 10 based on second distance information acquired from a target wireless marker M included in the second positioning group. When the estimation unit determines that the error between the position of the moving body 10 in the first positioning group and the position of the moving body 10 in the second positioning group is within a predetermined error range, the travel instruction unit causes the moving body 10 to automatically travel based on the position of the moving body 10 in the first positioning group and map information.

[0207] The above-mentioned configuration can improve the accuracy of estimating the position of the moving body 10. Therefore, the reliability of the moving body control device 20 can be improved.

[0208] According to this embodiment, when the error range is 1 m or more, the measurement instruction unit 33 instructs the wireless marker M to be used to measure the distance between the wireless marker M to be used and the moving body 10 using a WLAN frame. When the error range is less than 1 m, the measurement instruction unit 33 instructs the wireless marker M to be used to measure the distance between the wireless marker M to be used and the moving body 10 using WLAN sensing.

[0209] With the above-mentioned configuration, when it is necessary to reduce the error range, it is possible to easily deal with the problem by switching from distance measurement using WLAN frames to distance measurement using WLAN sensing, thereby reducing the burden on the operator.

[0210] According to this embodiment, the points P1 to P4 are set on the travel route 5 at points where the traveling direction of the moving object 10 changes.

[0211] The above-described configuration makes it possible to suppress an increase in the number of times that an operation instruction is given to the moving body 10. Therefore, the load on the moving body control device 20 can be reduced.

[0212] According to this embodiment, the mobile object control system 1 includes a mobile object 10, a plurality of wireless markers M, and a mobile object control device 20. The plurality of wireless markers M are arranged in an area in which the mobile object 10 can travel automatically. The mobile object control device 20 is capable of communicating with the plurality of wireless markers M. The mobile object control device 20 includes a setting unit 29, a selection unit 31, a measurement instruction unit 33, an estimation unit, and a travel instruction unit.

[0213] The setting unit 29 sets map information related to a travel route 5 of the moving body 10. The selection unit 31 selects a plurality of wireless markers M to be used from among the plurality of wireless markers M based on the travel route 5. The measurement instruction unit 33 instructs the wireless markers M to be used to measure the distance between the wireless markers M to be used and the moving body 10.

[0214] The estimation unit acquires distance information including the measured distance from the wireless marker M to be used, and estimates the position of the moving body 10 based on the acquired distance information. The travel instruction unit automatically drives the moving body 10 along the travel route 5 based on the estimated position of the moving body 10 and map information.

[0215] Each wireless marker M includes a measurement unit 67 and a wireless transmission unit 51. The measurement unit 67 measures the distance to the moving body 10 based on an instruction from the moving body control device 20. The wireless transmission unit 51 transmits distance information including the measured distance to the moving body control device 20.

[0216] With the above-mentioned configuration, the position of the moving body 10 is measured using a plurality of target wireless markers M, so there is no problem even if some of the wireless markers M1 to M20 are hidden by process equipment due to changes in the process layout. The wireless markers M1 to M20 can be placed above or below an area in which the moving body 10 can travel automatically, and can also be buried in the ground of the area.

[0217] Therefore, even if the process layout is changed, the worker can cause the moving body to travel automatically by simply setting new map information regarding the travel route 5 without having to re-lay out the multiple wireless markers M.

[0218] Therefore, according to the mobile object control system 1 of the present embodiment, even when the process layout is changed, the mobile object 10 can be automatically driven without increasing the burden on the workers.

[0219] According to this embodiment, the setting unit 29 sets an error range that is permissible when the estimation unit estimates the position of the moving body 10. The measurement instruction unit 33 selects one of distance measurement using a WLAN frame and distance measurement using WLAN sensing according to the size of the error range, and instructs the wireless marker M to be used to measure the distance using the selected one. The measurement unit 67 measures the distance using the selected one based on an instruction from the moving body control device 20.

[0220] With the above-mentioned configuration, when it is necessary to reduce the error range, it is possible to easily deal with the problem by switching from distance measurement using WLAN frames to distance measurement using WLAN sensing, thereby reducing the burden on the operator.

[0221] According to this embodiment, a plurality of wireless markers M are arranged on the ceiling of an area within a building where the moving object 10 can travel automatically.

[0222] With the above-mentioned configuration, even if the process layout is changed, the wireless markers M are arranged on the ceiling of the area where the mobile body 10 can travel automatically, and therefore are not hidden by the process equipment. Therefore, the mobile body 10 can travel automatically without fail.

[0223] [Variations] In the above-described embodiment, the mobile object control system 1 is provided in the factory 3, but is not limited to this. The mobile object control system 1 may be provided in a building other than the factory 3, or outdoors.

[0224] In the above-described embodiment, the number of moving bodies 10 is one, but is not limited to this. The number of moving bodies 10 may be more than one. In this case, the moving body control device 20 and the wireless marker M store identification information of each moving body 10 and identify each moving body using the identification information. Each moving body automatically travels along the travel route 5 while keeping a distance from other moving bodies under the control of the moving body control device 20.

[0225] In the above-described embodiment, the operation instructions for the moving body 10 are transmitted at the points P1 to P4 on the travel route 5, but the present invention is not limited to this. The operation instructions for the moving body 10 may be transmitted, for example, in a manufacturing area on the travel route 5 by following a similar procedure.

[0226] Although the present embodiment has been described above, the present embodiment is not limited to this, and various modifications are possible within the scope of the gist of the present embodiment. [Explanation of symbols]

[0227] 1. Mobile control system 5. Route 10 Mobile 20 Mobile control device 29 Setting section 31 Selection Department 33 Measurement instruction section 35 Position calculation section 37 Judgment section 39 Matching Execution Department 41 Instruction part 51 Radio transmitter 67 Measuring part M Radio Marker P1, P2, P3, P4 points

Claims

1. A mobile object control device capable of communicating with a plurality of wireless markers arranged in an area in which a mobile object can travel automatically, A setting unit that sets map information related to a travel route of the moving object; a selection unit that selects a plurality of wireless markers to be used from the plurality of wireless markers based on the travel route; a measurement instruction unit that instructs the wireless marker to measure a distance between the wireless marker and the moving object; an estimation unit that acquires distance information including the measured distance from the wireless marker to be used and estimates a position of the moving object based on the acquired distance information; a travel instruction unit that automatically drives the moving object along the travel route based on the estimated position of the moving object and the map information; A mobile control device comprising:

2. the setting unit sets an allowable error range when the estimation unit estimates a position of the moving object; 2. The mobile control device according to claim 1, wherein the measurement instruction unit selects one of distance measurement using a wireless local area network (WLAN) frame and distance measurement using WLAN sensing depending on the size of the error range, and instructs the wireless marker to be used to measure the distance using the selected one.

3. A plurality of measurement points at which the distance is measured are set on the travel route, The mobile object control device according to claim 1 , wherein the selection unit selects a plurality of the wireless markers to be used from the plurality of wireless markers based on magnitudes of elevation and depression angles of the plurality of wireless markers at the plurality of measurement points.

4. The selection unit selects, for each wireless marker, a largest elevation / depression angle among the elevation / depression angles at the plurality of measurement points; the selection unit selects, from among the plurality of wireless markers, a plurality of wireless markers having elevation / depression angles larger than a threshold as the wireless markers to be used; the selection unit groups a predetermined number of wireless markers to be used in order from the largest elevation / depression angle as a first positioning group, and groups a next predetermined number of wireless markers to be used in order from the largest elevation / depression angle as a second positioning group; The estimation unit estimates a position of the moving object based on first distance information acquired from the wireless marker of the target of use included in the first positioning group; The estimation unit estimates a position of the moving object based on second distance information acquired from the wireless marker of the target of use included in the second positioning group; 4. The mobile body control device according to claim 3, wherein when an error between the position of the mobile body in the first positioning group and the position of the mobile body in the second positioning group is within a predetermined error range, the driving instruction unit automatically drives the mobile body based on the position of the mobile body in the first positioning group and the map information.

5. The measurement instruction unit instructs the target wireless marker to measure a distance between the target wireless marker and the moving object by using a wireless local area network (WLAN) frame when the error range is 1 m or more; The mobile body control device according to claim 4 , wherein the measurement instruction unit instructs the wireless marker to be used to measure the distance between the wireless marker to be used and the mobile body using WLAN sensing when the error range is less than 1 m.

6. The mobile object control device according to claim 3 , wherein the plurality of measurement points are set at points on the travel route where a traveling direction of the mobile object is changed.

7. A moving body, A plurality of wireless markers that are placed in an area in which the moving object can travel automatically; a mobile object control device capable of communicating with the plurality of wireless markers; Equipped with The mobile object control device includes: A setting unit that sets map information related to a travel route of the moving object; a selection unit that selects a plurality of wireless markers to be used from the plurality of wireless markers based on the travel route; a measurement instruction unit that instructs the wireless marker to measure a distance between the wireless marker and the moving object; an estimation unit that acquires distance information including the measured distance from the wireless marker to be used and estimates a position of the moving object based on the acquired distance information; a travel instruction unit that automatically drives the moving object along the travel route based on the estimated position of the moving object and the map information; Equipped with Each radio marker is A measurement unit that measures a distance to the moving body based on an instruction from the moving body control device; a transmission unit that transmits the distance information including the measured distance to the mobile object control device; A mobile control system comprising:

8. the setting unit sets an allowable error range when the estimation unit estimates a position of the moving object; the measurement instruction unit selects one of distance measurement using a wireless local area network (WLAN) frame and distance measurement using WLAN sensing according to a size of the error range, and instructs the wireless marker to measure the distance using the selected one; The mobile object control system according to claim 7 , wherein the measurement unit measures the distance using the selected one of the two based on an instruction from the mobile object control device.

9. The mobile object control system according to claim 7 , wherein the plurality of wireless markers are arranged on a ceiling of an area within a building where the mobile object can travel automatically.

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