JP2023072733A - Moving body controller, moving body control method, and moving body system - Google Patents

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

The present disclosure relates to movement control of moving devices.

Mobile robots, such as automatic guided vehicles, are used in order to eliminate labor shortages and improve efficiency in the transportation of goods in distribution warehouses and manufacturing factories. These mobile robots may be remotely controlled by a central control unit for their moving paths and moving speeds, or may control their moving paths and moving speeds autonomously. In both cases safe and efficient transportation of goods is required. That is, it is necessary to control the movement so as to prevent the mobile robot from colliding and improve the transportation efficiency.

Regarding this safe movement control, there is a technique disclosed in Patent Document 1, for example. Specifically, "each autonomous mobile device 2 in the autonomous mobile system 1 includes an autonomous traveling means 3 for autonomous traveling, a device information storage means 4 that stores information indicating its own identification information and its own operating state, and other An interface 5 for communicating with the autonomous mobile device 2 and for the user to input a destination and travel commands, and extracting other autonomous mobile devices that move on a route intersecting the route of the autonomous mobile device when heading to the next node. Target device extraction means 6, time determination means 7 for determining whether the time for both devices to reach the intersection when another autonomous mobile device 2 is extracted is within a predetermined time, and arrival at the intersection A movement determination means 8 is provided for determining which device should be moved first based on the priority of both devices when the time comes within a predetermined time. This can prevent mobile robots from colliding.

However, in the above technique, information on the opponent mobile robot is collected by communication, and collision of the mobile robots cannot be prevented if this communication fails and the information on the opponent mobile robot cannot be obtained. In particular, when wireless communication means is used, there may be an area where communication becomes temporarily difficult, such as behind an obstacle, and it is necessary to prepare for communication failure. In addition, although not disclosed in Patent Document 1, safety can be ensured by, for example, stopping on the spot when communication difficulties are detected, or moving at an extremely low speed to the extent that it will not break even if it collides. can easily be considered, but in that case the transportation efficiency will decrease.

In addition, regarding the occurrence of areas where communication is difficult, for example, Patent Document 2 states, "A mobile object management system (100, 200) includes a plurality of mobile objects (10) each moving according to a guidance command and each moving object (10) moving according to a guidance command. An operation management device (50) for transmitting a guidance command to a body, connected wirelessly to each moving object, and connected to the operation management device wirelessly or by wire for communication between each moving object and the operation management device. and at least one wireless access point (2) that relays the wireless access point (2). Using the state data obtained from each mobile object, the operation management device determines that if the first guidance command meets the condition indicating that it is difficult to maintain communication, , change the first lead command to the second lead command.” technology. This allows the mobile robot to travel safely while avoiding areas where communication is difficult.

However, the above technique cannot improve the transportation efficiency.

Japanese Patent Application No. 2006-113687 Japanese Patent Application No. 2019-148870

Therefore, regarding movement control of mobile robots such as automatic guided vehicles, it is possible to suppress collisions of mobile robots even when the mobile robots travel in areas where communication is difficult, and to improve transportation efficiency when suppressing collisions. A technology to

One aspect of the present disclosure is a mobile body control device that controls movement of a plurality of mobile bodies within a mobile body control area using wireless communication. The mobile body control device includes one or more arithmetic units and one or more storage devices. The one or more storage devices store management information indicating current positions of the plurality of moving bodies. The one or more computing devices identify an exclusive control area based on the measurement result of wireless communication quality in the mobile object control area, and determine that the number of mobile objects simultaneously existing in the exclusive control area is equal to or less than a specified number. movement of the plurality of moving bodies is controlled based on the management information.

Collisions can be suppressed even when a mobile object moves in an area where wireless communication is difficult, and transportation efficiency can be improved when collisions are suppressed.

1 is a configuration diagram of a mobile control system according to an embodiment of the present specification; FIG. 1 is a functional configuration diagram of a mobile body control device according to an embodiment of the present specification; FIG. 1 is a hardware configuration diagram of a mobile body control device according to an embodiment of the present specification; FIG. Functional configuration diagram of a moving body according to an embodiment of the present specification FIG. 1 is a communication sequence diagram between a mobile unit and a mobile unit control device according to the embodiment of the present specification; FIG. 2 is a communication sequence diagram between a mobile unit and a mobile unit control device according to the embodiment of the present specification; Example of transportation information table in mobile unit control device Example of mobile status table in mobile controller Warehouse MAP information table in mobile control device Item information table in mobile Operation status table in moving object Flowchart 1 of mobile control function Flowchart 2 of mobile control function Flowchart of moving route calculation function Flowchart of mobile state management function Diagram of route control Example 1 of exclusive control according to the embodiment of this specification Example 2 of exclusive control according to the embodiment of this specification Illustration of exclusive control

First, common parts of the following embodiments will be described. FIG. 1 is a configuration diagram of a mobile system for distribution warehouses according to an embodiment of the present specification. It should be noted that the mobile system of the embodiment of this specification can be applied to sites other than distribution warehouses. The mobile body system includes a plurality of mobile bodies 101 and a mobile body control device 102 that controls movement of the plurality of mobile bodies 101 within a movement control area.

The moving body 101 carries goods within the warehouse 107 . The mobile control system includes a mobile control unit (WCS) 102, a user interface 103 for entering settings and displaying mobile operating status, and a radio base station 104. FIG. In the warehouse 107, shelves 105 for storing articles are installed, and there is a difficult-to-communication area (hereinafter referred to as an NG area) 106 caused by the shadow of the shelves and the stored articles.

The mobile unit control device 102 divides the entire warehouse 107 into mesh-like partial areas as indicated by dotted lines in FIG. 1, and manages the communication quality in units of these areas. This enables efficient management. For example, the minimum value of the side length of the mesh area can be determined based on the position coordinate measurement accuracy (A) of the moving object, the ability to stop the moving object (B), and the size of the moving object (C). The shape (size) of each mesh region is determined, for example, so that each moving body can automatically avoid collisions with other moving bodies. Note that wireless communication quality may not be managed for each mesh area.

More specifically, for example, the larger one of (A) and (B)+(C) may be set as the minimum value of the mesh side length. By reducing the size of the mesh to the extent that it can be guaranteed that mobile bodies will not collide, it is possible to manage difficult-to-communicate areas in smaller units, and reduce the number of times the mobile exclusion control is executed according to the embodiments of the present specification. As a result, it is possible to further suppress the decrease in transport work efficiency due to movement exclusion control for ensuring safety.

The communication quality is constantly measured while the moving object 101 is carrying an article. As a result, it is possible to efficiently measure the communication quality in the area where the moving object moves. Communication quality may 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 region from a plurality of measurement values include methods such as using an average value and using a maximum value.

Although the details will be described in FIG. 2A, the NG area 106 is an area where the communication quality measurement value is degraded and communication is determined to be difficult. In this area, for safety reasons, it is conceivable that the moving bodies are driven at a low speed or temporarily stopped so as not to collide with each other. However, this can reduce the efficiency of conveying the goods.

In the embodiment of the present specification, exclusive control of the movement of each moving object 101 is realized so that the number of moving objects equal to or less than a specified number always exists 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 in the NG area. The prescribed number is, for example, 1, which can more reliably prevent collisions of the moving bodies 101 within the NG area. In addition, transportation efficiency is improved by moving at the same speed as outside the NG area. An example of the method will be described in more detail below. In the following, it is assumed that the number of moving bodies allowed to exist in the NG area is one.

FIG. 2A is a functional configuration diagram of the mobile body control device 102. As shown in FIG. A mobile control function 201, a set value holding function 202, a communication function 203, a mobile status table 204, a transportation information table 205, a warehouse MAP information table 206, a communication quality judgment function 207, and a moving route calculation function 208 are implemented. . The mobile unit status table 204 , transportation information table 205 , and warehouse MAP information table 206 are examples of management information for controlling and managing the mobile unit 101 .

The mobile unit control function 201 is mainly a function of calculating the moving route and speed of the mobile unit 101 , creating transportation information and a moving route notification message, and transmitting them to the mobile unit 101 . The processing of the mobile body control function 201 will be described in detail with reference to FIGS. 11 and 12. FIG.

The setting value holding function 202 is a function for holding and managing setting values input from the user interface 103 . The set values are, for example, the total number of mobile units, mobile stopping performance of mobile units (the number of seconds from receiving a stop instruction to stopping), high speed of mobile units, low speed of mobile units, communication quality threshold ( communication delay time, communication data loss rate, etc.), moving route recalculation instructions.

The movement route recalculation instruction is normally off, but is turned on when the user gives an instruction from the user interface 103 . When it is ON, the movement exclusive control of the moving body according to this embodiment is immediately executed, and when the control is completed, the movement route recalculation instruction is turned OFF. The user monitors the movement status of the mobile body displayed on the user interface 103, and when the user determines that it is necessary, the mobile body movement control system according to the present embodiment is forced to move the mobile body. It is for executing exclusive control.

A communication function 203 is a function for transmitting and receiving information to and from the mobile object 101 . The mobile unit status table 204, the transportation information table 205, and the warehouse MAP information table 206 will be described with reference to FIGS. 6, 7, and 8, respectively. The communication quality determination function 207 compares the communication quality measurement value measured by the mobile object 101 with the communication quality threshold held by the setting value holding function 202, and if the communication quality measurement value exceeds the communication quality threshold, that is, This is a function of determining an area where the communication quality is measured by the mobile object 101 as an NG area when the measured communication quality is inferior to a predetermined communication quality. The movement route calculation function 208 is a function that implements the movement exclusive control of the moving object. Details will be described with reference to FIG.

FIG. 2B is a block diagram schematically showing a hardware configuration example of the mobile body control device 102. As shown in FIG. The mobile body control device 102 includes an arithmetic device 121 having arithmetic performance, and a main storage device 122 that provides a storage area for storing programs to be executed by the arithmetic device 121 and data to be processed. The arithmetic device 121 is, for example, a CPU including one or more cores, and the main storage device 122 is, for example, a RAM including a volatile storage area.

The mobile body control device 102 further includes a communication interface 126 that performs data communication with other computer devices 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, or the like. ,including. The mobile body control device 102 also includes an input device 124 that receives an operation from the user, and an output device 125 that presents the output results of each process to the user.

Input device 124 includes, for example, a keyboard and mouse, and output device 125 includes, for example, monitor and printer. These components of mobile controller 102 can communicate via internal bus 127 .

Programs to be executed by the arithmetic device 121 and data to be processed are loaded from the auxiliary storage device 123 to the main storage device 122, for example. Functional units such as the mobile unit control function 201, the setting value holding function 202, the communication quality determination function 207, and the moving route calculation function 208 shown in FIG. . Also, the communication function 203 can be implemented by the computing device 121 using the communication interface 126 . Various data or information such as the mobile unit status table 204, the warehouse MAP information table 206, and the transportation information table 209 shown in FIG. 2A can be stored in the auxiliary storage device 123, for example.

The mobile control device 102 may be a physical computer system (one or more physical computers) or a system built on a computing resource group (a plurality of computing resources) such as a cloud platform. The mobile body control device 102 may be a mobile device such as a smart phone or a tablet. A computer system or group of computing resources includes one or more interface devices, one or more storage devices (including, for example, main storage devices and auxiliary storage devices), and one or more computing devices.

When a function is realized by executing a program by an arithmetic device, the function is at least a part of the arithmetic device because the specified processing is performed using a storage device and/or an interface device as appropriate. may The processing described with function as the subject may be processing performed by a system having an arithmetic device or its processor.

Programs may be installed from program sources. The program source may be, for example, a program distribution computer or a computer-readable storage medium (eg, 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.

FIG. 3 is a functional configuration diagram of the moving body 101. As shown in FIG. The functional configuration of the mobile object 101 can be realized by, for example, the computer configuration described with reference to FIG. 2B. A state management function 301, an article information table 302, a wireless communication function 303, an operating state table 304, a communication quality measurement function 305, a position coordinate acquisition function 306, and a travel function 307 are implemented.

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

A wireless communication function 303 is a function for executing wireless communication via a wireless LAN or the like. The article information table 302 and the operating state table 304 will be described with reference to FIGS. 9 and 10, respectively.

The communication quality measurement function 305 is a function for measuring communication delay time and communication data loss rate with the mobile control device 102 . Generally, when transmitting information, a transmission time and a unique sequence number are assigned to each piece of information to be transmitted. When information is received, the communication delay time is calculated from the difference between the reception time and the assigned transmission time. Also, information loss is detected by a unique sequence number assigned to each piece of information, and an information loss rate is calculated. This information loss rate calculation is performed periodically, for example, every 10 seconds.

The position coordinate acquisition function 306 is a function for acquiring the current position of the moving object within the warehouse. For example, a marker such as a QR code (registered trademark) indicating positional information in the warehouse can be placed in each area, and the positional information can be obtained by photographing the marker with a camera mounted on a moving body. The running function 307 is a function in which the moving body receives a remote instruction or runs autonomously.

FIG. 4 is a sequence diagram of the position/velocity information notification message 401 and the transportation information and moving route notification message 402. As shown in FIG. Details will be described with reference to FIG. 11, but when the mobile body control device 102 receives the position/speed information notification message 401 from the mobile body 101, it determines the communication quality of the area. As a result, when an area that has been a normal area has changed to an NG area, or conversely when an NG area has changed to a normal area, route control is executed for the related moving object 101 . The mobile controller 102 prepares and sends a transport information and travel route notification message 402 to the associated mobile 101 .

FIG. 5 is a sequence diagram of the operating status notification message 501 and the transportation information and moving route notification message 402. As shown in FIG. This transportation information and moving route notification message 402 has the same content as that of FIG. 4, and is also used in FIG. Details will be described in FIG. The mobile body control device 102 creates transportation information and a moving route notification message 402 and transmits it to the mobile body 101 .

FIG. 6 is an example of the transportation information table 205 held by the mobile body control device 102 . The transportation information table 205 shows a transportation order 601, a unique item number 602, an item shelf coordinate 603 indicating a storage position, a transportation destination coordinate 604, and an allocation state 605 for items stored in the warehouse. . Allocation state 605 indicates whether the shipment of the item has been allocated to any mobiles.

The mobile body control device 102 assigns the mobile body 101 to transport each article based on the transportation information table 205, and calculates the movement route and the movement speed. For example, the mobile body control device 102 allocates the mobile body closest to the article shelf coordinates 603 on which the article is arranged among the mobile bodies waiting for transportation to carry the article. Also, a moving route with the shortest moving distance is calculated, and a moving speed is calculated so that the moving time including deceleration at a curve is the shortest.

FIG. 7 is an example of the mobile body state table 204 held by the mobile body control device 102 . Mobile status table 204 shows unique mobile ID 701 , status 702 , position coordinates 703 , velocity 704 , consignment item number 705 , movement path and velocity 706 .

The status 702 holds whether the moving body 101 is transporting an item, is stopped, or is moving toward an item to be transported. A position coordinate 703 indicates the current position of the mobile object 101, is managed separately from the mesh that manages the communication quality, and indicates the physical position within the warehouse. Generally, a certain point in the warehouse is taken as a reference point, and relative plane coordinates (unit: meter) from that point are used.

A speed 704 is the moving speed of the moving object when it passes through the position coordinates 703, that is, the current moving speed. The transported article number 705 is the number of the article to be carried by the moving body, which is the article number 602 in FIG. If the transport item number 705 is not assigned, it means that the mobile unit 101 is on standby. A movement path and speed 706 indicates the movement path and movement speed of each moving body 101 for transporting an article, and is the calculation result of the movement path calculation function 208 . After three numbers in parentheses, the first two indicate position coordinates, and the third number indicates the movement speed to the next position coordinate.

FIG. 8 is an example of the warehouse MAP information table 206 held by the mobile unit control device 102 . The warehouse MAP information table 206 shows an object 801 , start point coordinates 802 and end point coordinates 803 . The target object 801 indicates whether each target object is an article shelf 105 existing in the warehouse, a passageway of a moving body, or an NG area 106 . Start point coordinates 802 and end point coordinates 803 represent the size of the object (unit: meter). These coordinates are in the same coordinate system as the position coordinates 703 in FIG. It should be noted that each time the communication quality is determined as described in FIG. 4, the number of rows in the NG area increases or decreases. Details of this will be described in FIG.

FIG. 9 is an example of an article information table 302 held by the moving body 101. As shown in FIG. The article information table 302 shows information on articles carried by the moving body 101 . The article information table 302 shows an article number 901 , article shelf coordinates 902 , and destination coordinates 903 . These have the same contents as the article number 602, article shelf coordinates 603, and transportation destination coordinates 604 in FIG. The moving body 101 moves to the place indicated by the goods shelf coordinates 902 and loads the goods. Then, it moves to the location indicated by the destination coordinates 903 and unloads the article. The moving body 101 repeats this work.

FIG. 10 shows the operating state table 304 held by the moving body 101. As shown in FIG. The operating state table 304 shows status 1001 , position coordinates 1002 , speed 1003 and communication quality measurement value 1004 . These are notified to the mobile body control device 102 by the position/velocity information notification message 401 . Status 1001, position coordinates 1002, and speed 1003 are the same as status 702, position coordinates 703, and speed 704 in FIG.

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

At step 1103 , the mobile body control function 201 updates the status 702 , position coordinates 703 and speed 704 in the mobile body state table 204 . At step 1104 , the mobile unit control function 201 adds or deletes rows relating to the NG area in the warehouse MAP information table 206 .

Specifically, the mobile unit control function 201 performs NG area determination based on the communication quality measurement value notified from the mobile unit 101 by the communication quality determination function 207, as described with reference to FIG. 2A. As a result, when the existing NG area is changed to the normal area, the mobile body control function 201 deletes the row in the warehouse MAP information table 206 . Conversely, when the number of NG areas increases, a new row is added to the warehouse MAP information table 206 . At this time, the area including the position coordinates 703 of the moving object 101 is set as a newly added NG area.

In step 1105, the mobile unit control function 201 determines whether there is a mobile unit 101 that has the area on the movement route when the NG area is reduced as a result of the communication quality judgment, or the movement status table 204 in FIG. Check the Route and Velocity 706 column. If it exists, proceed to step 1106; otherwise, proceed to step 1107.

At step 1106 , the mobile body control function 201 cancels the exclusive control of the mobile body 101 . That is, the moving speed that has been reduced due to waiting for exclusive control on the moving route is updated to the maximum speed. Then proceed to step 1108 .

In step 1107, as in step 1105, it is confirmed whether the number of NG areas has increased as a result of determining the communication quality in step 1104 and, if so, whether there is a moving object 101 having the NG area on the moving route. If NO, return to step 1101 . If YES, at step 1301 , the moving route calculation function 208 calculates the moving route for the moving object 101 . The details of this moving route calculation will be described with reference to FIG.

In step 1108 , mobile unit control function 201 creates transportation information and travel route notification message 402 containing the calculated or updated travel route and travel speed, and sends it to mobile unit 101 .

At step 1201 in FIG. Upon receiving the message in step 1202, the mobile unit control function 201 calculates the moving route of the mobile unit 101 by using the moving route calculation function 208 based on the contents of the message in step 1301. FIG. Details of this will be described in FIG. Subsequently, in step 1203 , transportation information including the calculated moving route and moving speed and moving route notification message 402 are created and transmitted to the mobile unit 101 .

FIG. 13 is a flow chart of the movement route calculation function 208 of the mobile body control device. FIG. 15 shows a conceptual diagram of moving route calculation. The processing of FIG. 13 is executed for one target moving body 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 passing through the NG area. Also, as described with reference to FIG. 12, a travel route is calculated for the mobile unit 101 that receives the active status notification message 501 .

At step 1302, the movement route calculation function 208 calculates the shortest route with the shortest movement distance from the position coordinates 703 of the moving body 101 and the position coordinates of the destination point. As for the destination point, if an article to be transported has already been assigned to the moving body 101, the article number is obtained by referring to the article number to be transported 705 in FIG. The destination coordinates 604 in the line having the same article number 602 in FIG. 6 are the destination points. If the goods to be transported have not been allocated, the item number 602 with the smallest transport order 601 is searched for in the allocation status 605 of "unallocated" by referring to FIG. At this time, the article shelf coordinate 603 becomes the destination point.

At step 1303, the movement route calculation function 208 refers to the warehouse MAP information table 206 and checks whether the shortest route includes an NG area. If an NG area is included (1303: YES), go to step 1306; If the NG area is not included (1303: NO), there is no problem in traveling on the shortest route at the maximum speed.

At step 1306, the moving route calculation function 208 calculates the second shortest route by detouring the NG area. If there are multiple NG areas on the shortest route, a route that bypasses all the NG areas is selected. The following steps 1307-1310 are performed for each NG region on the path.

First, in step 1307, the movement route calculation function 208 finds out all moving objects that include the NG area found in step 1303 on the movement route. This is done by referring to the moving path and speed 706 of the moving body state table 204 .

At step 1308 , the moving route calculation function 208 calculates the entry time and leaving time of the NG area for all moving objects identified at step 1307 . This is done by referring to the position coordinates 703 and the moving path and speed 706 of the moving body state table 204 . A movement path and speed 706 represents the entire movement path of the moving body 101 . Since the position coordinates 703 represent the current position, they represent a point in the middle of the entire moving route.

A movement route calculation function 208 calculates the movement time for the remaining movement route from the current position to the destination point. By adding this movement time to the current time, the entry time to the NG area can be calculated. When passing through another NG area before arriving at the NG area, the waiting time at that time is also added. The leaving time can be obtained by calculating the length of the traveling direction of the moving body in the NG area, calculating the time required for the moving body to pass through assuming that the moving body moves at the maximum speed, and adding it to the entry time.

At step 1309, the moving route calculation function 208 determines that the time at which each moving body 101 enters the NG area calculated at step 1308 is later than the leaving time of all the moving bodies that previously entered the NG area. confirm. If YES, go to step 1304 ; if NO, go to step 1310 .

At step 1310, the movement route calculation function 208 calculates the movement exclusive control waiting time. The moving object control function 201 performs movement exclusion control so that multiple moving objects do not enter a certain NG area at the same time. That is, the moving speed of the following moving body is adjusted to delay the entry time so that the following moving body does not enter the NG area until the leaving time of the moving body that has previously entered the NG area has passed. The time delayed at this time is the migration exclusive control waiting time. By shortening this movement exclusive control waiting time, it is possible to improve the efficiency of transporting goods by the moving body 101 . Details of this will be explained in FIG.

At step 1304, the movement path calculation function 208 calculates the movement time for each calculated movement path. At this time, if there is a waiting time due to movement exclusive control calculated in step 1310, this is added. When the moving body 101 passes through multiple NG areas, the waiting times of all NG areas are added.

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 no NG area is included (1303: NO), the shortest distance is selected.

If it is determined in step 1303 that the NG area is included (1303: YES), the route with the shortest travel time is selected from the detour route and the shortest route. In other words, if the calculated amount of time delay (waiting time) is larger than the travel time delay calculated assuming that the area where the communication quality is degraded is detoured, the detour route is preferentially selected. .

In one example, when a certain NG area is determined to be an NG area and a predetermined specified time has passed, the movement route calculation function 208 calculates a movement route including the NG area even if the movement time is not the shortest. preferentially selected as a result of By intentionally causing the mobile object 101 to pass through the NG area, it becomes possible to measure and update the communication quality of the NG area. As a result, it is possible to periodically ascertain that the communication quality has returned to normal, and to suppress execution of unnecessary exclusive control.

FIG. 14 is a flow chart of the state management function 301 of the moving body 101. As shown in FIG. 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 . Subsequently, in step 1402, the communication quality measurement value is acquired from the communication quality measurement function 305. FIG.

Furthermore, at step 1403 , the state management function 301 acquires the current speed from the running function 307 . At step 1404, a position/velocity information notification message containing these three pieces of information is created and transmitted while moving. Finally, in step 1405, an operating status notification message containing the contents of the operating status table 304 is created and sent.

FIG. 15 is a conceptual diagram of moving route calculation. Assume that the moving body 101 at the position shown in the figure moves to the transportation destination indicated by the black circle. Although the movement route P1 with the shortest distance is calculated, the NG area 106 exists on the route. Therefore, the detour route P2 with the second shortest distance is also calculated.

FIG. 16 is a diagram showing a case where the movement exclusion control of FIG. 13 is required. In the figure, the movement paths of the moving body 101A and the moving body 101B intersect, and there is an NG area 106A at the intersection. Under this condition, while the moving object 101A is staying in the NG area 106A, the moving object 101B also enters the NG area 106A. Due to the difficulty of communication, it is predicted that they will hide behind shelves and will not be able to recognize each other until just before, and will collide. In order to avoid this, the moving body 101A is caused to pass through the NG area 106A first, and then the moving body 101B is caused to pass through the NG area 106A. Note that the moving body 101B can enter the NG area 106A after the moving body 101A has entered the NG area 106B.

FIG. 17 is a diagram showing another example requiring the movement exclusive control of FIG. NG areas 106A and 106B are present in portions where the movement paths of the moving body 101A and the moving body 101B overlap. The exclusive control first causes the moving object 101A to pass through the NG area 106A, and then causes the moving object 101B to pass through the NG area 106A. Also, the moving object 101A is allowed to pass through the NG area 106B first, and the moving object 101B is allowed to pass through the NG area 106B later. Immediately after the moving body 101A passes through the NG area 106A or NG area 106B, the moving body 101B is caused to enter the NG area 106A or NG area 106B.

FIG. 18 is a conceptual diagram of movement exclusion control. FIG. 18 schematically shows a stay time 1801 of a moving object 101 in a certain NG area in chronological order. A stay time 1801 represents the time from when the moving object 101 enters the NG area until it leaves the area. That is, one moving body occupies the NG area during the staying time.

In order to realize this, when the time of stay of a certain mobile body collides with the time of entry of another mobile body into the NG area, the time of entry of the subsequent mobile body into the NG area is set after the time of the end of the stay time. delay to This delayed time is the movement exclusive control waiting time 1802 . In order to delay the entry time of the subsequent moving body, the moving body is temporarily stopped before the NG area or the moving speed is reduced.

Some of the functions of the mobile body control device 102 and the management information for realizing the functions may be omitted. For example, the mobile body control device 102 may execute exclusive control of the mobile body 101 in the NG area based on the current position of the mobile body 101 without determining the path of the mobile body.

In addition, the present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above-described embodiments have been described in detail in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the described configurations. In addition, it is possible to replace 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. Moreover, it is possible to add, delete, or replace a part of the configuration of each embodiment with another configuration.

Further, each of the configurations, functions, processing units, etc. described above may be realized by hardware, for example, by designing a part or all of them using an integrated circuit. Moreover, each of the above configurations, functions, etc. may be realized by software by a processor interpreting and executing a program for realizing each function. Information such as programs, tables, and files that implement each function can be placed in a recording device such as a memory, a hard disk, an SSD (Solid State Drive), or a recording medium such as an IC card or SD card.

In addition, the control lines and information lines indicate those considered necessary for explanation, and not all control lines and information lines are necessarily indicated on the product. In fact, it may be considered that almost all configurations are interconnected.

101 moving body 102 moving body control device (WCS)
106 communication difficult area (NG area)
201 Moving body control function 206 Warehouse MAP information table 208 Movement route calculation function 301 State management function 401 Position and speed information notification 402 Transportation information, movement route notification 501 Operation status notification 1801 Time required for the moving body to pass through the NG area 1802 Exclusive control wait time

Claims (9)

A mobile object control device that controls 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 current positions of the plurality of mobile bodies;
The one or more computing devices,
Identifying an exclusive control area based on a measurement result of wireless communication quality in the mobile control area,
A moving body control device that controls movement of the plurality of moving bodies based on the management information so that the number of moving bodies that exist simultaneously within the exclusive control area is equal to or less than a specified number. The mobile body control device according to claim 1,
The moving body control device, wherein the prescribed number is one. The mobile body control device according to claim 1,
A mobile body control device that receives the measurement results of the wireless communication quality from the plurality of mobile bodies. The mobile body control device according to claim 1,
The moving body control area is divided in advance into a plurality of partial areas,
The mobile body control device, wherein the one or more arithmetic devices determine the exclusive control region for each of the plurality of partial regions. The mobile body control device according to claim 4,
Each partial area of the plurality of partial areas has a size that allows each moving body of the plurality of moving bodies to automatically avoid a collision with another moving body. The mobile body control device according to claim 1,
the shortest route from the current position of the first moving body to the destination passes through the exclusive control area;
The one or more computing devices,
Estimate the travel time of the shortest route including the waiting time for passing the exclusive control area of the first moving body,
estimating the travel time of the detour route of the first moving body that detours the exclusive control area;
A mobile body control device that gives priority to the detour route over the shortest route when the travel time of the detour route is shorter than the travel time of the shortest route. In the mobile body control device according to claim 6,
the wireless communication quality is measured by the plurality of mobile bodies;
The moving body control device, wherein the one or more arithmetic devices give priority to the shortest route over the detour route when a specified time has passed since the exclusive control area was specified. A method for a mobile control device to control movement of a plurality of mobiles within a mobile control area using wireless communication, comprising:
The mobile body control device holds management information indicating current positions of each of the plurality of mobile bodies,
In the method, the mobile body control device
Acquiring a measurement result of wireless communication quality in the mobile control area,
Identifying an exclusive control area based on the measurement result,
controlling movement of the plurality of moving bodies based on the management information so that the number of moving bodies that exist simultaneously within the exclusive control is equal to or less than a prescribed number. A mobile system,
a plurality of moving bodies;
a mobile body control device that controls movement of the plurality of mobile bodies within the mobile body control area using wireless communication;
The moving body control device is
identifying an exclusive control area based on a measurement result of wireless communication quality in the mobile control area;
A moving body system that controls the movement of the plurality of moving bodies based on the current positions of the plurality of moving bodies so that the number of moving bodies simultaneously existing within the exclusive control area is equal to or less than a specified number.

Images