MOBILE BODY CONTROL DEVICE, METHOD FOR CONTROLLING MOBILE BODY, AND MOBILE BODY SYSTEM

Abstract

To make it possible to prevent collision of a moving body even in the event that the moving body moves through an area where it is hard to perform communications, and enhance transport efficiency while preventing the collision.SOLUTION: A moving body controller uses wireless communications to control movements of plural moving bodies within a moving body control area. The moving body controller includes one or more arithmetic units and one or more memory units. The one or more memory units store pieces of management information representing present positions of the respective moving bodies. The one or more arithmetic units identify an exclusive control area on the basis of a result of measurement of wireless communication quality within the moving body control area, and perform control based on the pieces of management information the movements of the respective moving bodies so that the number of moving bodies concurrently existing within the exclusive control area will be equal to or smaller than a stipulated number of moving bodies.SELECTED DRAWING: Figure 13

Description

[Technical field]

[0001] The present disclosure relates to control of movement of a moving device. [Background technology]

[0002] Mobile robots such as automated guided vehicles are being used to resolve labor shortages and improve efficiency in goods transportation operations in logistics warehouses and manufacturing plants. These mobile robots may be remotely controlled by a central control device for their movement path and speed, or each mobile robot may control its movement path and speed autonomously. In either case, safe and efficient goods transportation is required. In other words, it is necessary to control the movement of mobile robots in a way that prevents collisions and improves transportation efficiency.

[0003] Regarding this safe movement control, for example, there is a technology disclosed in Patent Document 1. Specifically, it discloses that "each autonomous mobile device 2 in the autonomous mobile system 1 is equipped with an autonomous traveling means 3 for autonomous traveling, a device information storage means 4 that stores its own identification information and information indicating its own operating status, an interface 5 for communication with other autonomous mobile devices 2 and for a user to input a destination and a traveling command, a target device extraction means 6 that extracts other autonomous mobile devices moving on a route that intersects with the route of the autonomous mobile device when heading to the next node, a time determination means 7 that determines whether the time when both devices reach the intersection will be within a predetermined time when the other autonomous mobile device 2 is extracted, and a movement determination means 8 that determines which device will move first based on the priority of both devices when the time ...

[0004] However, in the above technology, information on the other mobile robot is collected through communication, and if this communication fails and the information on the other mobile robot cannot be obtained, collisions between the mobile robots cannot be prevented. In particular, when using wireless communication means, there may be areas where communication is temporarily difficult, such as behind obstacles, and it is necessary to prepare for communication failures. Although not disclosed in Patent Document 1, it is easy to imagine that safety could be ensured by stopping on the spot when it detects that communication is difficult, or by moving at an extremely slow speed that will not break even if it collides, but in such cases, transportation efficiency would decrease.

[0005] Regarding the occurrence of areas where communication is difficult, for example, Patent Document 2 discloses a technology that "a mobile object management system (100, 200) has a plurality of mobile objects (10) each moving according to a guidance command, a traffic management device (50) that transmits a guidance command to each mobile object, and at least one wireless access point (2) that is connected to each mobile object by radio and to the traffic management device by radio or wire and relays communication between each mobile object and the traffic management device. Each mobile object generates status data (32) indicating a communication status by communicating with a specified wireless access point, and transmits the status data to the outside via the specified wireless access point. The traffic management device uses the status data acquired from each mobile object to change the first guidance command to a second guidance command when the first guidance command meets a condition indicating that communication is difficult to maintain." This allows the mobile robot to travel safely while avoiding areas where communication is difficult.

[0006] However, the above techniques cannot improve transportation efficiency. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent Application No. 2006-113687 [Patent Document 2] Patent Application No. 2019-148870 Summary of the Invention [Problem to be solved by the invention]

[0008] Therefore, with regard to the movement control of mobile robots such as automatic guided vehicles, there is a demand for technology that can prevent collisions between mobile robots even when the mobile robots are traveling in areas where communication is difficult, and that can improve transportation efficiency when preventing collisions. [Means for solving the problem]

[0009] One aspect of the present disclosure is a mobile object control device that controls the movement of multiple mobile objects within a mobile object control area using wireless communication. The mobile object control device includes one or more arithmetic devices and one or more storage devices. The one or more storage devices store management information indicating a current position of each of the multiple mobile objects. The one or more arithmetic devices identify an exclusive control area based on a measurement result of wireless communication quality within the mobile object control area, and control the movement of the multiple mobile objects based on the management information so that the number of mobile objects simultaneously present within the exclusive control area is equal to or less than a specified number. Effect of the Invention

[0010] Even when a mobile object moves through an area where wireless communication is difficult, collisions can be prevented, and transportation efficiency can be improved when collisions are prevented. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a block diagram of a mobile control system according to an embodiment of the present specification. [Figure 2A] Functional configuration diagram of a mobile control device according to an embodiment of the present specification [Figure 2B] FIG. 1 is a hardware configuration diagram of a mobile control device according to an embodiment of the present specification. [Diagram 3] Functional configuration diagram of a moving body according to an embodiment of the present specification [Figure 4] A communication sequence diagram between a mobile object and a mobile object control device in an embodiment of this specification, part 1 [Diagram 5] Communication sequence diagram 2 between a mobile object and a mobile object control device in an embodiment of this specification [Figure 6] Example of transportation information table in mobile control device [Figure 7] Example of a mobile unit state table in a mobile unit control device [Figure 8] Warehouse map information table in the mobile control device [Figure 9] Information on items in a moving vehicle [Figure 10] Mobile vehicle operation status table [Figure 11] Flowchart of the mobility control function, part 1 [Figure 12] Flowchart of the mobility control function, part 2 [Figure 13] Flowchart of the route calculation function [Figure 14] Flowchart of mobile state management function [Figure 15] Routing control diagram [Figure 16] Example 1 of exclusive control according to the embodiment of this specification [Figure 17] Example 2 of exclusive control according to the embodiment of this specification [Figure 18] Exclusive control diagram DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] First, the common parts to the following embodiments will be described. FIG. 1 is a configuration diagram of a mobile body system for a logistics warehouse according to an embodiment of this specification. Note that the mobile body system of the embodiment of this specification can be applied to a site other than a logistics warehouse. The mobile body system includes multiple mobile bodies 101 and a mobile body control device 102 that controls the movement of the multiple mobile bodies 101 within a movement control area.

[0013] A mobile object 101 carries an item in a warehouse 107. The mobile object control system includes a mobile object control device (WCS) 102, a user interface 103 for inputting setting values ​​and displaying the operating status of the mobile object, and a wireless base station 104. In the warehouse 107, shelves 105 for storing items are installed, and there are communication-difficult areas (hereinafter referred to as NG areas) 106 caused by the shadows of the shelves and stored items.

[0014] The mobile object control device 102 divides the entire warehouse 107 into mesh-like partial regions as shown by dotted lines in Fig. 1, and manages communication quality for each region. This enables efficient management. For example, the minimum length of the sides of a mesh region can be determined based on the accuracy of the position coordinate measurement of the mobile object (A), the stopping ability of the mobile object (B), and the size of the mobile object (C). The shape (size) of each mesh region is determined, for example, so that each mobile object can automatically avoid collision with other mobile objects. Note that wireless communication quality does not have to be managed for each mesh region.

[0015] More specifically, for example, the larger of (A) and (B) + (C) may be set as the minimum value of the length of the mesh side. By making the mesh smaller within a range that can guarantee that moving objects will not collide, it is possible to manage areas where communication is difficult in smaller units, and the number of times that the movement exclusive control of the embodiment of this specification is executed can be reduced. This makes it possible to further suppress the decrease in efficiency of transportation work caused by movement exclusive control for ensuring safety.

[0016] The communication quality is constantly measured by the mobile object 101 while it is transporting goods. This allows the communication quality of the area in which the mobile object moves to be measured efficiently. The communication quality may also be measured by another device installed in the warehouse. The mobile object 101 may measure the communication quality multiple times while moving within one area. Methods for determining the communication quality measurement value of the area from multiple measurement values ​​include using the average value, using the maximum value, and so on.

[0017] Details will be described in the explanation of FIG. 2A, but an area where the communication quality measurement value has deteriorated and communication is judged to be difficult is the NG area 106. In this area, for safety reasons, it is considered that moving objects are made to travel at a low speed or to stop temporarily to prevent collisions between moving objects. However, this may reduce the efficiency of transporting goods.

[0018] In the embodiment of this specification, exclusive control of the movement of each moving body 101 is realized so that there are always a specified number or less of moving bodies within the NG area 106. The NG area 106 is an example of an exclusive control area. This can reduce the possibility of collisions between moving bodies within the NG area. The specified number is, for example, one body, which can more reliably prevent collisions between the moving bodies 101 within the NG area. In addition, transportation efficiency is improved by moving the moving bodies at the same speed as outside the NG area. An example of this method will be described in more detail below. In the following, it is assumed that the number of moving bodies permitted to exist in the NG area is one. EXAMPLES

[0019] 2A is a functional configuration diagram of the mobile object control device 102. Implemented are a mobile object control function 201, a setting value holding function 202, a communication function 203, a mobile object status table 204, a transportation information table 205, a warehouse MAP information table 206, a communication quality judgment function 207, and a movement route calculation function 208. The mobile object status table 204, the transportation information table 205, and the warehouse MAP information table 206 are examples of management information for controlling and managing the mobile object 101.

[0020] The mobile object control function 201 is a function that mainly calculates the moving route and speed of the mobile object 101, creates transportation information and a moving route notification message, and transmits them to the mobile object 101. The processing of the mobile object control function 201 will be described in detail with reference to Figs. 11 and 12.

[0021] The setting value holding function 202 is a function for holding and managing setting values ​​input from the user interface 103. The setting values ​​include, for example, the total number of moving objects, the moving object stopping performance of the moving object (the number of seconds from receiving a stop instruction to stopping), the high speed of the moving object, the low speed of the moving object, the communication quality threshold (communication delay time, communication data loss rate, etc.), and a movement route recalculation instruction.

[0022] The movement route recalculation instruction is normally off, but is turned on when the user issues a command from the user interface 103. When it is on, the exclusive movement control of the moving object according to this embodiment is immediately executed, and when the control is completed, the movement route recalculation instruction is turned off. This is because the user is monitoring the movement status of the moving object displayed on the user interface 103, and when the user determines it is necessary, the moving object movement control system according to this embodiment is forced to execute exclusive movement control of the moving object.

[0023] The communication function 203 is a function for transmitting and receiving information to and from the mobile object 101. The mobile object status table 204, the transportation information table 205, and the warehouse MAP information table 206 are respectively described in Fig. 6, Fig. 7, and Fig. 8. The communication quality determination function 207 is a function for comparing the communication quality measurement value measured by the mobile object 101 with the communication quality threshold value stored in the setting value storage function 202, and determining that the area where the mobile object 101 measured the communication quality is an NG area if the communication quality measurement value exceeds the communication quality threshold value, that is, if the measured communication quality is inferior to a predetermined communication quality. The movement route calculation function 208 is a function for realizing exclusive movement control of the mobile object. It will be described in detail in Fig. 13.

[0024] 2B is a block diagram showing a schematic example of a hardware configuration of the mobile object control device 102. The mobile object control device 102 includes a calculation device 121 having calculation performance, and a main memory device 122 that provides a memory area for storing programs executed by the calculation device 121 and data to be processed. The calculation device 121 is, for example, a CPU including one or more cores, and the main memory device 122 is, for example, a RAM including a volatile memory area.

[0025] The mobile object control device 102 further includes a communication interface 126 that performs data communication with other computers and external storage devices, and an auxiliary storage device 123 that provides a non-volatile storage area using a HDD (Hard Disk Drive), flash memory, etc. The mobile object control device 102 also includes an input device 124 that accepts operations from a user, and an output device 125 that presents the output results of each process to the user.

[0026] The input device 124 includes, for example, a keyboard and a mouse, and the output device 125 includes, for example, a monitor and a printer. These components of the mobile control device 102 can communicate with each other via an internal bus 127.

[0027] The programs executed by the arithmetic device 121 and data to be processed are loaded, for example, from the auxiliary storage device 123 to the main storage device 122. Functional units such as a mobile object control function 201, a setting value holding function 202, a communication quality determination function 207, and a movement route calculation function 208 shown in FIG. 2A can be implemented by the arithmetic device 121 executing corresponding programs. In addition, the communication function 203 can be implemented by the arithmetic device 121 using the communication interface 126. Various data or information such as a mobile object status table 204, a warehouse MAP information table 206, and a transportation information table 209 shown in FIG. 2A can be stored, for example, in the auxiliary storage device 123.

[0028] The mobile object control device 102 may be a physical computer system (one or more physical computers) or a system built on a group of computing resources (multiple computing resources) such as a cloud platform. The mobile object control device 102 may be a portable device such as a smartphone or tablet. The computer system or the group of computing resources includes one or more interface devices, one or more storage devices (including, for example, a main storage device and an auxiliary storage device), and one or more arithmetic devices.

[0029] When a function is realized by executing a program by a computing device, the defined process is performed using a storage device and / or an interface device, etc., as appropriate, and therefore the function may be considered to be at least a part of the computing device. A process described using a function as the subject may be considered to be a process performed by the computing device or a system having a processor thereof.

[0030] The program may be installed from a program source. The program source may be, for example, a program distribution computer or a computer-readable storage medium (for example, a computer-readable non-transitory storage medium). The description of each function is an example, and multiple functions may be combined into one function, or one function may be divided into multiple functions.

[0031] Fig. 3 is a functional configuration diagram of the moving object 101. The functional configuration of the moving object 101 can be realized, for example, by a computer configuration such as that described with reference to Fig. 2B. A status management function 301, an item information table 302, a wireless communication function 303, an operation status table 304, a communication quality measurement function 305, a position coordinate acquisition function 306, and a traveling function 307 are implemented.

[0032] The state management function 301 is a function for creating and transmitting a position and speed information notification message 401 for notifying the mobile object control device 102 of its own current position, movement speed, and communication quality measurement value. It also has a function for creating and transmitting an operation state notification message for notifying the mobile object control device 102 of its own operation state, such as arrival at a movement destination.

[0033] The wireless communication function 303 is a function for executing wireless communication via a wireless LAN, etc. The item information table 302 and the operation state table 304 will be described with reference to Figs. 9 and 10, respectively.

[0034] The communication quality measurement function 305 is a function that measures the communication delay time and communication data loss rate between the mobile object control device 102. In general, when transmitting information, a transmission time and a unique sequence number are assigned to each piece of information to be transmitted. When receiving information, the communication delay time is calculated from the difference between the reception time and the assigned transmission time. In addition, a missing piece of information (loss) is detected by the unique sequence number assigned to each piece of information, and the information loss rate is calculated. This calculation of the information loss rate is performed periodically, for example, every 10 seconds.

[0035] The position coordinate acquisition function 306 is a function for acquiring the current position of the mobile object in the warehouse. For example, a marker such as a QR code (registered trademark) indicating the position information in the warehouse is installed in each area, and the marker is photographed by a camera mounted on the mobile object to acquire the position information. The traveling function 307 is a function for the mobile object to travel under remote instructions or autonomously.

[0036] 4 is a sequence diagram of a position / speed information notification message 401 and a transportation information and movement route notification message 402. Details will be described in FIG. 11, but when the mobile object control device 102 receives the position / speed information notification message 401 from the mobile object 101, it judges the communication quality of the relevant area. As a result, if a normal area changes to a NG area, or conversely, if a NG area changes to a normal area, it executes route control for the associated mobile object 101. The mobile object control device 102 creates a transportation information and movement route notification message 402 and transmits it to the associated mobile object 101.

[0037] Fig. 5 is a sequence diagram of an operating status notification message 501 and a transportation information and movement route notification message 402. This transportation information and movement route notification message 402 has the same content as that in Fig. 4, and is also used in Fig. 5. Although details will be described in Fig. 12, when the mobile object control device 102 receives an operating status notification message 501 from a mobile object 101, it executes route control for the mobile object 101. The mobile object control device 102 creates a transportation information and movement route notification message 402 and transmits it to the mobile object 101.

[0038] 6 is an example of a transport information table 205 held by the mobile object control device 102. The transport information table 205 indicates, for each item stored in the warehouse, a transport order 601, a unique item number 602, item shelf coordinates 603 indicating the storage position, destination coordinates 604, and an allocation status 605. The allocation status 605 indicates whether the transport of the item has been allocated to any mobile object.

[0039] The mobile object control device 102 assigns a mobile object 101 to transport each item based on the transport information table 205, and calculates the travel route and travel speed. For example, among the mobile objects waiting to be transported, the mobile object control device 102 assigns the mobile object that is closest to the item shelf coordinates 603 where the item is located to transport the item. In addition, the mobile object control device 102 calculates the travel route that will result in the shortest travel distance, and calculates the travel speed, including deceleration around curves, so as to minimize the travel time.

[0040] 7 shows an example of the moving object status table 204 held by the moving object control device 102. The moving object status table 204 indicates a unique moving object ID 701, a status 702, position coordinates 703, a speed 704, a transported item number 705, a moving route and a speed 706.

[0041] Status 702 holds whether the mobile unit 101 is transporting an item, is stopped, or is moving toward the item to be transported. Location coordinates 703 indicate the current location of the mobile unit 101, and are managed separately from the mesh that manages communication quality, and indicate the physical location within the warehouse. Generally, a certain point within the warehouse is taken as the reference point, and the relative planar coordinates (unit: meters) from that point are expressed.

[0042] Speed ​​704 is the moving speed of the moving object when it passes position coordinate 703, that is, the current moving speed. Transported item number 705 is the number of the item transported by the moving object, which corresponds to item number 602 in FIG. 6. If the transported item number 705 is not assigned, it means that the moving object 101 is waiting. Movement path and speed 706 indicates the movement path and movement speed of each moving object 101 for transporting an item, and is the calculation result of the movement path calculation function 208. After the three numbers in parentheses, the first two indicate the position coordinates, and the third number indicates the movement speed to the next position coordinate.

[0043] FIG. 8 is an example of the warehouse map information table 206 held by the mobile object control device 102. The warehouse map information table 206 shows objects 801, start point coordinates 802, and end point coordinates 803. The object 801 shows whether each object is an item shelf 105 in the warehouse, a passageway for a mobile object, or a NG area 106. The start point coordinates 802 and end point coordinates 803 show the size of the object (unit: meters). These coordinates are in the same coordinate system as the position coordinates 703 in FIG. 7. Each time the communication quality described in FIG. 4 is judged, the number of rows in the NG area increases or decreases depending on the result. Details of this will be explained in FIG. 11.

[0044] FIG. 9 is an example of an item information table 302 held by the mobile object 101. The item information table 302 shows information on items transported by the mobile object 101. The item information table 302 shows an item number 901, item shelf coordinates 902, and destination coordinates 903. These are the same as the item number 602, item shelf coordinates 603, and destination coordinates 604 in FIG. 6, respectively, and are notified from the mobile object control device 102 by a transportation information and movement route notification message 402. The mobile object 101 moves to the location indicated by the item shelf coordinates 902 and loads the item. It then moves to the location indicated by the destination coordinates 903 and unloads the item. The mobile object 101 repeats this operation.

[0045] 10 shows an operational status table 304 held by the mobile object 101. The operational status table 304 indicates a status 1001, a position coordinate 1002, a speed 1003, and a communication quality measurement value 1004. These are notified to the mobile object control device 102 by a position and speed information notification message 401. The status 1001, the position coordinate 1002, and the speed 1003 have the same contents as the status 702, the position coordinate 703, and the speed 704 in FIG.

[0046] 11 and 12 are flowcharts of the mobile object control function 201 of the mobile object control device 102. In Fig. 11, in step 1101, the mobile object control function 201 waits for a position and speed information notification message 401 from the mobile object 101. Upon receiving the message in step 1102, the mobile object control function 201 updates the mobile object status table 204 in step 1103 and updates the warehouse MAP information table 206 in step 1104 based on the message contents.

[0047] In step 1103, the mobile object control function 201 updates the status 702, the position coordinates 703, and the speed 704 in the mobile object status table 204. In step 1104, the mobile object control function 201 adds or deletes rows in the warehouse MAP information table 206 that relate to NG areas.

[0048] Specifically, as described in Fig. 2A, the mobile object control function 201 performs a NG area determination based on the communication quality measurement value notified from the mobile object 101 by the communication quality determination function 207. If an existing NG area changes to a normal area as a result, the mobile object control function 201 deletes the row in question from the warehouse MAP information table 206. Conversely, if an NG area is increased, a new row is added to the warehouse MAP information table 206. At this time, the area including the position coordinates 703 of the mobile object 101 is regarded as the newly increased NG area.

[0049] In step 1105, when the NG area is reduced as a result of the communication quality judgment, the mobile object control function 201 checks the moving path and speed 706 column of the mobile object status table 204 in Fig. 7 to see if there is a mobile object 101 that has the area on its moving path. If there is, the process proceeds to step 1106, and if there is not, the process proceeds to step 1107.

[0050] In step 1106, the moving object control function 201 cancels the exclusive control of the moving object 101. That is, the moving speed that has been reduced due to waiting for the exclusive control on the moving route is updated to the maximum speed. Next, the process proceeds to step 1108.

[0051] In step 1107, it is confirmed in the same manner as in step 1105 whether the number of NG areas has increased as a result of the communication quality determination in step 1104, and if so, whether there is a moving body 101 that has the NG area on its movement route. If NO, the process returns to step 1101. If YES, in step 1301, the movement route of the moving body 101 is calculated by the movement route calculation function 208. Details of this movement route calculation will be described with reference to FIG.

[0052] In step 1108 , the mobile entity control function 201 creates a transportation information and movement route notification message 402 including the calculated or updated movement route and movement speed, and transmits it to the mobile entity 101 .

[0053] 12, in step 1201, the mobile object control function 201 waits for an operating state notification message 501 from the mobile object 101. When the message is received in step 1202, in step 1301, the mobile object control function 201 calculates the movement route of the mobile object 101 by the movement route calculation function 208 based on the message contents. This will be described in detail in Fig. 13. Next, in step 1203, the transportation information and movement route notification message 402 including the calculated movement route and movement speed is created and transmitted to the mobile object 101.

[0054] Fig. 13 is a flowchart of the movement route calculation function 208 of the mobile object control device. A conceptual diagram of the movement route calculation is shown in Fig. 15. The process of Fig. 13 is executed for one target moving object 101. As described with reference to Fig. 11, when a new NG area occurs, the process of Fig. 13 is executed for each moving object 101 that passes through the NG area. Also, as described with reference to Fig. 12, a movement route is calculated for a moving object 101 that has received an operating state notification message 501.

[0055] In step 1302, the movement path calculation function 208 calculates the shortest route with the shortest movement distance from the position coordinates 703 of the moving object 101 and the position coordinates of the destination point. For the destination point, if a transported item has already been assigned to the moving object 101, the transported item number 705 in Fig. 7 is referenced to obtain the item number. The destination coordinates 604 in the row with the same item number 602 in Fig. 6 becomes the destination point. If a transported item has not been assigned, Fig. 6 is referenced to find the item number 602 with the smallest transport order 601 among those with an assignment status 605 of "Not assigned". At this time, the item shelf coordinates 603 becomes the destination point.

[0056] In step 1303, the movement route calculation function 208 checks whether or not the shortest route includes a NG area by referring to the warehouse map information table 206. If the NG area is included (1303: YES), the process proceeds to step 1306. If the NG area is not included (1303: NO), there is no problem with always traveling at maximum speed on the shortest route, so the shortest route and maximum speed are set as the movement route and movement speed, and the process proceeds to step 1304.

[0057] In step 1306, the movement route calculation function 208 calculates the second shortest route that bypasses the no-go area. If there are multiple no-go areas on the shortest route, the route that bypasses all of the no-go areas is selected. The following steps 1307 to 1310 are performed for each no-go area on the route.

[0058] First, in step 1307, the movement route calculation function 208 finds out all moving objects whose movement route includes the NG area found in step 1303. This is done by referring to the movement route and speed 706 in the moving object state table 204.

[0059] In step 1308, the movement path calculation function 208 calculates the entry times and exit times of the NG area for all moving objects identified in step 1307. This is done by referring to the position coordinates 703 and the movement path and speed 706 in the moving object status table 204. The movement path and speed 706 represent the entire movement path of the moving object 101. The position coordinates 703 represent the current position, and therefore represent a point along the entire movement path.

[0060] The movement path calculation function 208 calculates the movement time for the remaining movement path from the current position to the destination point. The entry time into the NG area can be calculated by adding this movement time to the current time. If another NG area is passed before arriving at the NG area, the waiting time at that time is also added. The exit time can be calculated by calculating the length of the NG area in the direction of travel of the moving object, and calculating the time required for the moving object to pass through assuming that the moving object is moving at its maximum speed, and adding this to the entry time.

[0061] In step 1309, the movement path calculation function 208 confirms that the entry time of each moving body 101 into the NG area calculated in step 1308 is later than the exit time of all moving bodies that previously entered the NG area. If YES, proceed to step 1304, and if NO, proceed to step 1310.

[0062] In step 1310, the movement path calculation function 208 calculates the movement exclusive control waiting time. The moving object control function 201 performs movement exclusive control so that multiple moving objects do not enter a certain NG area at the same time. In other words, the movement speed of the following moving object is adjusted to delay the entry time so that the following moving object does not enter the NG area until the exit time of the moving object that entered the NG area first has passed. The delayed time at this time is the movement exclusive control waiting time. By shortening this movement exclusive control waiting time, the efficiency of transporting goods by the moving object 101 can be improved. This will be described in detail in FIG. 18.

[0063] In step 1304, the movement route calculation function 208 calculates the movement time for each calculated movement route. At this time, if there is a waiting time due to the movement exclusive control calculated in step 1310, this is added. If the moving object 101 passes through multiple NG areas, the waiting times for all the NG areas are added.

[0064] Finally, in step 1305, the movement route calculation function 208 selects the movement route with the shortest movement time and the movement speed at that time as the result of the movement route calculation function. If it is determined in step 1303 that an NG area is not included (1303: NO), the shortest distance is selected.

[0065] If it is determined in step 1303 that an NG area is included (1303: YES), the route with the shorter travel time is selected from the detour route and the shortest route. In other words, if the calculated time delay (waiting time) is greater than the travel time delay calculated assuming that the area with deteriorated communication quality is detouring, the detour route is selected with priority.

[0066] In one example, if a predetermined time has passed since a certain NG area was determined to be an NG area, the movement route calculation function 208 preferentially selects a route that includes the NG area as the result of the movement route calculation, even if the movement time is not the shortest. By intentionally making the moving body 101 pass through the NG area, it becomes possible to measure and update the communication quality of the NG area. This makes it possible to periodically grasp that the communication quality has returned to normal and to suppress the implementation of unnecessary exclusive control.

[0067] 14 is a flowchart of the state management function 301 of the mobile unit 101. This flowchart is executed periodically. First, in step 1401, the state management function 301 acquires position coordinate information from the position coordinate acquisition function 306. Then, in step 1402, the state management function 301 acquires a communication quality measurement value from the communication quality measurement function 305.

[0068] Furthermore, in step 1403, the state management function 301 acquires the current speed from the driving function 307. In step 1404, a position and speed information notification message is created including these three pieces of information, and is transmitted. Finally, in step 1405, an operation state notification message including the contents of the operation state table 304 is created and transmitted.

[0069] Fig. 15 is a conceptual diagram of a movement route calculation. Let us assume that a moving object 101 located at the position in the figure moves to a destination represented by a black circle. A movement route P1 with the shortest distance is calculated, but an NG area 106 exists on the route. Therefore, a detour route P2 with the second shortest distance is also calculated.

[0070] FIG. 16 is a diagram showing a case where the movement exclusive control of FIG. 13 is required. In the diagram, the movement paths of the moving body 101A and the moving body 101B intersect, and there is a NG area 106A at the intersection. If things continue as they are, the moving body 101B will enter the NG area 106A while the moving body 101A is staying in the NG area 106A. Due to the difficulty in communication, the moving body 101B will hide behind a shelf and will not be able to recognize each other until just before, and it is predicted that they will collide. To avoid this, the moving body 101A is made to pass through the NG area 106A first, and the moving body 101B is made to pass through the NG area 106A afterwards. Note that the moving body 101B can enter the NG area 106A after the moving body 101A has entered the NG area 106B.

[0071] Fig. 17 is a diagram showing another example where the movement exclusion control of Fig. 13 is required. There are NG areas 106A and 106B in the part where the movement paths of the moving body 101A and the moving body 101B overlap. The exclusion control makes the moving body 101A pass through the NG area 106A first, and then the moving body 101B pass through the NG area 106A. Also, the moving body 101A passes through the NG area 106B first, and then the moving body 101B passes through the NG area 106B. Immediately after the moving body 101A passes through the NG area 106A or NG area 106B, the moving body 101B enters the NG area 106A or NG area 106B.

[0072] Fig. 18 is a conceptual diagram of the movement exclusion control. It is a schematic time series diagram of the stay time 1801 of a moving object 101 in a certain NG area. The stay time 1801 represents the time from when the moving object 101 enters the NG area to when it leaves. In other words, one moving object occupies the NG area during the stay time.

[0073] To achieve this, when the stay time of a certain moving object overlaps with the entry time of another moving object into the NG area, the entry time of the subsequent moving object into the NG area is delayed until after the end of the stay time. This delay time is the movement exclusive control waiting time 1802. In order to delay the entry time of the subsequent moving object, the subsequent moving object may stop temporarily just before the NG area or may slow down its movement speed.

[0074] Some of the functions of the mobile object control device 102 and the management information for implementing the functions may be omitted. For example, the mobile object control device 102 may execute exclusive control of the mobile object 101 in the NG area based on the current position of the mobile object 101 without determining the route of the mobile object.

[0075] The present invention is not limited to the above-mentioned embodiment, but includes various modified examples. For example, the above-mentioned embodiment has been described in detail to clearly explain the present invention, and is not necessarily limited to those including all of the configurations described. It is also possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. It is also possible to add, delete, or replace a part of the configuration of each embodiment with another configuration.

[0076] In addition, the above-mentioned configurations, functions, processing units, etc. may be realized in part or in whole by hardware, for example, by designing them as integrated circuits. In addition, the above-mentioned configurations, functions, etc. may be realized in software by a processor interpreting and executing a program that realizes each function. Information such as the program, table, file, etc. that realizes each function can be stored in a memory, a recording device such as a hard disk or SSD (Solid State Drive), or a recording medium such as an IC card or SD card.

[0077] In addition, the control lines and information lines shown are those that are considered necessary for the explanation, and not all control lines and information lines in the product are necessarily shown. In reality, it can be considered that almost all components are connected to each other. [Explanation of symbols]

[0078] 101 Mobile 102 Mobile Control System (WCS) 106 Communication difficult area (NG area) 201 Mobile control function 206 Warehouse MAP information table 208 Movement route calculation function 301 State Management Function 401 Position speed information notification 402 Transportation information, travel route notification 501 Operational status notification 1801 The time required for a moving object to pass through the NG area 1802 Exclusive control wait time

Claims

1. A mobile object control device that controls the movement of a plurality of mobile objects within a mobile object control area using wireless communication, one or more computing devices; one or more storage devices; the one or more storage devices store management information indicating a current position of each of the plurality of moving objects; The one or more computing devices, identifying an exclusive control area based on a measurement result of wireless communication quality within the mobile object control area received from the plurality of mobile objects; controlling the movement of the plurality of moving objects based on the management information so that the number of moving objects simultaneously present within the exclusive control area is equal to or less than a prescribed number; the shortest route from the current location of the first moving object to the destination passes through the exclusive control area; The one or more computing devices, Estimating a travel time of the shortest route, including a waiting time for the first moving object to pass through the exclusive control area; estimating a travel time of a detour route of the first moving object that detours around the exclusive control area; If the travel time of the detour route is shorter than the travel time of the shortest route, the detour route is prioritized over the shortest route; When a specified time has elapsed since the exclusive control area was identified, the one or more computing devices prioritize the shortest route over the detour route.

2. The mobile object control device according to claim 1, A mobile control device, wherein the specified number is 1.

3. A mobile object control device as claimed in claim 1, The mobile object control area is divided into a plurality of partial areas in advance, The one or more calculation devices determine the exclusive control area for each of the plurality of partial areas.

4. A mobile object control device according to claim 3, A mobile object control device, wherein each partial area of ​​the plurality of partial areas has a size that enables each mobile object of the plurality of mobile objects to automatically avoid collision with other mobile objects.

5. A method for controlling movement of a plurality of moving objects within a moving object control area by a moving object control device using wireless communication, comprising: the mobile object control device holds management information indicating a current position of each of the plurality of mobile objects; The method further comprises the steps of: receiving measurement results of wireless communication quality within the mobile control area from the plurality of mobile objects; Identifying an exclusive control area based on the measurement result; controlling the movement of the plurality of moving objects based on the management information so that the number of moving objects simultaneously present within the exclusive control area is equal to or less than a specified number; the shortest route from the current location of the first moving object to the destination passes through the exclusive control area; The method further comprises the steps of: Estimating a travel time of the shortest route, including a waiting time for the first moving object to pass through the exclusive control area; estimating a travel time of a detour route of the first moving object that detours around the exclusive control area; If the travel time of the detour route is shorter than the travel time of the shortest route, the detour route is prioritized over the shortest route; the shortest route is prioritized over the detour route if a prescribed time has elapsed since the exclusive control area was identified.

6. A mobile system, comprising: A plurality of moving bodies; a mobile object control device that controls the movement of the plurality of mobile objects within a mobile object control area using wireless communication; The mobile object control device includes: identifying an exclusive control area based on a measurement result of wireless communication quality within the mobile object control area received from the plurality of mobile objects; controlling the movements of the plurality of moving objects based on current positions of the plurality of moving objects so that the number of moving objects simultaneously present within the exclusive control area is equal to or less than a specified number; the shortest route from the current location of the first moving object to the destination passes through the exclusive control area; The mobile object control device includes: Estimating a travel time of the shortest route, including a waiting time for the first moving object to pass through the exclusive control area; estimating a travel time of a detour route of the first moving object that detours around the exclusive control area; If the travel time of the detour route is shorter than the travel time of the shortest route, the detour route is prioritized over the shortest route; A mobile system that prioritizes the shortest route over the detour route if a specified time has elapsed since the exclusive control area was identified.

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