Transport System

Abstract

To enhance accuracy of position estimation of a carrying robot.SOLUTION: A control unit (10) of a transport system (1) uses self-position information obtained from a transport robot (30) and information about the position of the transport robot included in distance information obtained from transport robots other than the transport robot in question to calculate estimated position information about the position of the transport robot.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a transport system equipped with a transport robot. [Background technology]

[0002] Self-propelled transport robots such as automated guided vehicles (AGVs) and automated guided forklifts (AGFs) have been proposed for use in factories, warehouses, etc. A transport system that realizes automation of transport in factories, etc. is configured by controlling a plurality of such transport robots by a control device through wireless communication. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-48689 A Summary of the Invention [Problem to be solved by the invention]

[0004] A transport robot that can determine its own position based on distance information obtained from distance sensors such as LiDAR (Light Detection And Ranging) and stereo cameras is also being considered. Such a transport robot can autonomously determine its travel route without the need to install guides showing a predetermined travel route on the floor of a factory or warehouse.

[0005] Therefore, the application of such a transport robot has the advantage of being able to build a flexible transport system that can handle a wide variety of transport tasks in factories and warehouses and can flexibly respond to changes in the line. However, a transport system that uses a transport robot that autonomously determines its travel route has a problem in that it is difficult to improve the accuracy of determining the position of the transport robot, compared to a transport system that uses a transport robot that travels only along a predetermined route along a guide.

[0006] In one aspect, the present invention has been made in consideration of the above-mentioned situation, and aims to improve the accuracy of determining the position of a transport robot in a transport system that uses a transport robot that autonomously determines its traveling route. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the present invention employs the following configuration: A transport system according to one aspect of the present invention includes a plurality of self-propelled transport robots and a control device that communicates with the plurality of transport robots, the transport robots each having a sensor that detects a distance to a surrounding object and outputs the distance information, and a self-position calculation unit that calculates self-position information related to the transport robot's own position using the distance information, the control device includes an inherent state acquisition unit that acquires the self-position information and the distance information from each of the plurality of transport robots, an estimated position calculation unit that calculates estimated position information related to the position of the transport robot using the self-position information acquired from the transport robot and information related to the position of the transport robot included in the distance information acquired from a transport robot other than the transport robot, and an estimated position transmission unit that notifies the transport robot of the estimated position of the transport robot.

[0008] According to the above configuration, in a transport system using a transport robot that autonomously determines its travel route, it is possible to improve the accuracy of determining the position of the transport robot.

[0009] In the transport system according to the above aspect, the estimated position calculation unit may calculate the estimated position information by using the self-position information acquired from the transport robot other than the transport robot. According to the above configuration, the method of calculating the estimated position information by the estimated position calculation unit is further specified.

[0010] In the transport system according to the above aspect, the self-location information and the estimated location information may each include information on a position on a floor surface where the transport robot is traveling and information on a direction of the transport robot. According to the above configuration, the self-location information and the estimated location information are more specifically specified.

[0011] In the transport system according to the above aspect, the transport robot may further include a travel mechanism for causing the transport robot to travel, and a travel control unit for controlling the travel mechanism and calculating odometry data of the transport robot, and the self-position calculation unit may be configured to calculate the self-position information based on the odometry data and the distance information. According to the above configuration, the method of calculating the self-position information by the self-position calculation unit is more specific.

[0012] In the transport system according to the above aspect, the transport robot may further include a slave storage unit that stores identification information of the transport robot, and a unique state notification unit that transmits unique information including the distance information and the self-position information attached to the identification information, and the unique state acquisition unit may further acquire the identification information from a plurality of the transport robots. With the above configuration, the transport robot can be easily identified when each unit of the control device handles information related to the transport robot.

[0013] The control device according to each aspect of the present invention may be realized by a computer. In this case, the control program of the control device that realizes the control device by the computer by operating the computer as each part (software element) of the control device, and the computer-readable recording medium on which it is recorded, also fall within the scope of the present invention. Effect of the Invention

[0014] According to one aspect of the present invention, in a transport system using a transport robot that autonomously determines a travel route, the accuracy of determining the position of the transport robot is improved. [Brief description of the drawings]

[0015] [Figure 1] 1 is a block diagram showing a configuration of a main part of a transport system according to an embodiment of the present invention. [Diagram 2] 1 is a diagram showing an example of an external shape of a transport robot of a transport system according to an embodiment of the present invention; [Diagram 3] 1 is a floor map diagrammatically illustrating an example of a factory to which a conveying system according to an embodiment of the present invention is applied; [Figure 4] 1A and 1B are diagrams for explaining a method in which a transport robot detects surrounding objects using a distance sensor. [Diagram 5] 5 is a graph showing distance information output by a distance sensor of a transport robot in the example shown in FIG. 4. FIG. [Figure 6] 1 is a diagram for explaining a method for the transport robot to detect surrounding objects using a distance sensor, and shows a situation in which an obstacle exists in a monitoring area. [Figure 7] FIG. 5 is a diagram showing a situation in which another transport robot is further present within the monitoring range of the transport robot in the example shown in FIG. 4. [Figure 8] 8 is a graph showing distance information output by a distance sensor of a transport robot in the example shown in FIG. 7. FIG. [Figure 9] FIG. 13 is a diagram showing a situation in which a specific transport robot is present within the monitoring range of a plurality of other transport robots. [Figure 10] 4 is a flowchart illustrating a characteristic operation executed by the transport system according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] [Embodiment] Hereinafter, an embodiment according to one aspect of the present invention will be described with reference to the drawings.

[0017] §1 Examples of application An example of a situation in which the present invention is applied will be described with reference to Fig. 1. Fig. 1 is a block diagram showing the configuration of a transport system 1 according to a first embodiment. The transport system 1 includes a control device 10 and a plurality of self-propelled transport robots 30. The control device 10 communicates with the plurality of transport robots 30 and issues instructions to each of the transport robots 30.

[0018] 1, the internal configuration of one transport robot 30 is shown in detail, but the other transport robots 30 have similar internal configurations. The transport robot 30 has a distance sensor 36 (sensor) that detects the distance to surrounding objects and outputs the distance information, and a self-position calculation unit 33 that calculates self-position information regarding its own position using the distance information.

[0019] The control device 10 has an inherent state acquisition unit 13 that acquires the self-position information and the distance information from each of the transport robots 30. The control device 10 has an estimated position calculation unit that calculates estimated position information regarding the position of the other transport robot using information regarding the position of the other transport robot contained in the distance information acquired from each of the transport robots 30 and the self-position information of the other transport robot. Furthermore, the control device 10 has an estimated position transmission unit that notifies the other transport robot of the estimated position of the other transport robot.

[0020] In the transport system 1 of embodiment 1, estimated position information, which is information regarding the position of the self-propelled transport robot 30, is calculated by the control device 10 based not only on the self-position information calculated by the transport robot 30 (hereinafter, "self-machine"), but also on the distance information from transport robots other than the transport robot 30 (hereinafter, "other machines").

[0021] Then, the estimated position information is notified to the transport robot 30, which is the transport robot itself, from the control device 10. Therefore, in the transport system 1, the transport robot 30 can estimate its own position based on the estimated position information with higher accuracy than the self-position information. Therefore, a transport system with higher accuracy of position estimation of the self-propelled transport robot can be realized.

[0022] §2 Configuration Example <Applications of the transport system> Fig. 2 is a diagram showing an example of the appearance of the transport robot 30 of the transport system 1 according to this application example. Fig. 3 is a diagram showing a schematic floor map of a factory 100, which is an example of an area such as a factory or warehouse to which the transport system 1 according to this application example can be applied.

[0023] A self-propelled transport robot 30 that transports objects to be transported, such as finished products, semi-finished products, parts, raw materials, tools, jigs, packaging materials, and cassettes for storing them, is deployed in the factory 100. Furthermore, a self-propelled transport robot 30M having a robot arm (manipulator) for grasping the object to be transported provided on the transport robot as a cart may be deployed as a part of the transport system 1.

[0024] The transfer robot 30M is an example of the transfer robot 30, and in the following description, is included in the transfer robot 30. The transfer robot 30 may take the form of an automatic guided vehicle, an AGF, or other self-propelled transfer device.

[0025] In the factory 100, shelves 110 on which the objects to be transported can be placed are installed. In addition, in the factory 100, production facilities are also installed for performing processing, assembly, treatment, inspection, etc. on the objects to be transported or using the objects to be transported. The transport robot 30 of the transport system 1 can transport the objects to be transported between these facilities.

[0026] 3, the position of each transport robot 30 is represented by XY coordinates defined on the floor of the factory 100. The orientation of each transport robot 30 is represented by an angle θ defined with respect to the XY coordinates. In this manner, the position and orientation of each transport robot 30 can be represented as (X, Y, θ). Hereinafter, in this specification, information relating to the position of the transport robot refers to information relating to the position and orientation (X, Y, θ) of such a transport robot.

[0027] <Conveyor system configuration overview> The following describes a more specific configuration example and operation of the transport system 1. As shown in Fig. 1, the transport system 1 includes a control device 10 and a plurality of self-propelled transport robots 30. The control device 10 is an information processing system that is responsible for managing transport and may also be called a transport system server (AMHS server: Automated Material Handling System Server) or the like.

[0028] Based on a command from a higher-level information processing system or the like, the control device 10 transmits more specific transport instructions to the transport robot 30 in the transport system 1. The control device 10 may be any information processing system capable of executing such processing, and does not need to be a device physically housed in a single housing.

[0029] When the transport system 1 is applied to a production factory, the upper information processing system that manages the production of products in the production factory is sometimes called a manufacturing execution system server (MES server).When the transport system 1 is applied to a logistics warehouse, the upper information processing system that manages the entry and exit of stored items in the logistics warehouse is sometimes called a warehouse management system server (WMS server).

[0030] <Configuration of the transport robot> 1, the transport robot 30 has the following functional blocks: an instruction receiving unit 31, a travel control unit 32, a self-position calculation unit 33, a specific state notification unit 34, and an estimated position acquisition unit 35. The transport robot 30 also has a distance sensor 36, a slave storage unit 37, a travel mechanism unit 38, and a slave communication unit 39.

[0031] The distance sensor 36 is disposed on the front side of the transfer robot 30, and monitors the forward traveling direction of the transfer robot 30. As shown in Fig. 2, in the specific example of the first embodiment, the distance sensor 36 is composed of two LiDARs, and can obtain distance information indicating the distance to an object existing within the monitoring area.

[0032] The monitored area may, for example, include a range of about 120° to the left and right from the front in the traveling direction of the transport robot 30. Examples of such distance information will be described later. Note that distance information is also generally called a distance image.

[0033] The number of LiDARs arranged on the transport robot 30 may be one or more, and if there are more than one, they may be arranged so as to monitor the rear as well. In addition, the type of distance sensor is not limited to LiDAR, and may be a sensor that acquires distance images such as a stereo camera or a ToF (Time-of-Flight) camera, or may be one that uses other methods.

[0034] The slave storage unit 37 is a recording device provided in the transport robot 30. The slave storage unit 37 stores identification information of the transport robot 30 and map information of the floor of the factory 100, and also stores various information and travel history necessary for the transport robot 30 to perform travel, a control program for the transport robot 30, etc., as appropriate.

[0035] The travel mechanism 38 is a mechanism for causing the transport robot 30 to travel on a floor surface, which is operated under the control of the travel control unit 32. In the external view of the transport robot 30 in FIG. 2, wheels 38A, which are part of the travel mechanism 38, are shown.

[0036] The slave communication unit 39 is a communication interface for the transport robot 30 to communicate with the control device 10. Since real-time distance information is included in the communication with the transport robot 30 through the slave communication unit 39, it is preferable that the communication is high-speed, low-latency, and multi-connection. Therefore, it is preferable that the slave communication unit 39 communicates with the master communication unit 19 of the control device 10 using 5G (5th Generation) communication or Wi-Fi 6 (Wi-Fi: registered trademark). In the external view of the transport robot 30 in FIG. 2, an antenna 39A that is a part of the slave communication unit 39 is shown.

[0037] The instruction receiving unit 31 is a functional block that receives instructions from the control device 10 via the slave communication unit 39. The travel control unit 32 is a functional block that controls the travel mechanism unit 38 and drives the transport robot 30. The travel control unit 32 also calculates odometry data based on operation information of each mechanism from the travel mechanism unit 38, specifically, the rotary encoder output of the motor, etc. The odometry data is information that indicates the position of the transport robot 30 during or after travel relative to the position of the transport robot 30 at a certain point in time.

[0038] The self-position calculation unit 33 is a functional block that calculates the approximate position of the transport robot 30 from the odometry data, and further calculates self-position information regarding the self-position of the transport robot 30 by comparing the distance information with map information around the approximate position. The inherent state notification unit 34 is a functional block that notifies the control device 10 of inherent information of the transport robot 30 via the slave communication unit 39. The estimated position acquisition unit 35 is a functional block that acquires estimated position information from the control device 10 via the slave communication unit 39. The estimated position information will be described later.

[0039] Here, the unique information refers to information about the unique state of each individual transport robot 30 itself, and includes distance information and self-position information. Furthermore, the unique information may include information about the operation of the transport robot 30, the loading state of the transport object, the remaining battery level, and other internal states of the transport robot 30.

[0040] As a basic operation, the transfer robot 30 performs required transfer according to instructions from the control device 10 as follows. The instruction receiving unit 31 receives a transfer instruction from the control device 10 via the slave communication unit 39. The travel control unit 32 controls the travel mechanism unit 38 based on information on the self-position and the position information of the transfer destination included in the transfer instruction, and causes the transfer robot 30 to travel to the transfer destination. At that time, the self-position calculation unit 33 continues to update the self-position information based on the odometry data from the travel control unit 32 and the distance information from the distance sensor 36.

[0041] <Control device configuration> 1, the control device 10 has functional blocks of a higher-level command receiving unit 11, an instruction issuing unit 12, an inherent state acquiring unit 13, a positional relationship calculating unit 14, an estimated position calculating unit 15, and an estimated position transmitting unit 16. The control device 10 also has a master storage unit 17, a higher-level communication unit 18, and a master communication unit 19.

[0042] The master storage unit 17 is a recording device provided in the control device 10. The master storage unit 17 stores map information of the floor of the factory 100 and the control program of the control device 10, and also stores unique information and operation logs of each transport robot 30 as appropriate. The upper communication unit 18 is a communication interface for the control device 10 to communicate with a higher-level information processing system. The master communication unit 19 is a communication interface for the control device 10 to communicate with the transport robot 30.

[0043] The upper command receiving unit 11 is a functional block that receives commands from a higher-level information processing system via the upper communication unit 18. The command issuing unit 12 issues commands to each of the transport robots 30 based on the commands from the higher-level information processing system, and transmits the commands to each of the transport robots 30 via the master communication unit 19.

[0044] At that time, the instruction issuing unit 12 issues an appropriate instruction to each of the transport robots 30 to execute a command from a higher-level information processing system, with reference to the inherent state of each of the transport robots 30 acquired by the inherent state acquiring unit 13. The functions of the positional relationship calculating unit 14, the estimated position calculating unit 15, and the estimated position transmitting unit 16 will be described later.

[0045] <Principle of Estimated Position Calculation> Hereinafter, the principle of calculating the estimated position of the transport robot 30 in the transport system 1 according to the configuration example will be described with reference to Fig. 4 to Fig. 9. Fig. 4 is a diagram showing a situation in which the transport robot 30 measures the distance to a surrounding object using the distance sensor 36 on the floor of the factory 100. Fig. 5 is a diagram showing the distance information output by the distance sensor 36 at that time in the form of a graph.

[0046] The map information includes information about the positions of shelves and production equipment placed on the floor of the factory 100. For the production equipment 120a shown in Fig. 4, information about the positions of the four corners of the casing is registered in the map information as point landmarks MC1 to MC4.

[0047] Information about the positions of lines (sides) connecting corners of the production facility 120a is registered in the map information as line landmarks ML1 to ML4. Similarly, point landmarks MC5 to MC8 and line landmarks ML5 to ML8 are registered in the map information for the production facility 120b.

[0048] In Fig. 4, the monitoring range R of the distance sensor 36 of the transfer robot 30 is indicated by a dotted line. Fig. 5 is a diagram showing distance information in a graph, with the horizontal axis representing the angle from the front of the transfer robot 30, i.e., the orientation with respect to the transfer robot 30, and the vertical axis representing the distance from the reference point of the transfer robot 30. The monitoring range R is also shown in Fig. 5. As shown in Fig. 5, the distance information output by the distance sensor 36 includes information on the distance to an object located within the monitoring range R.

[0049] The self-position calculation unit 33 calculates the approximate position, including the orientation of the transport robot 30, from information about the past self-position and odometry data, and matches the map information of the vicinity of the area where the monitoring range R is assumed to be located with the distance information. Since the approximate position calculated from the odometry data contains an error, a deviation occurs between the map information and the distance information. The self-position calculation unit 33 calculates self-position information, which is information about the position of the transport robot 30 itself, by correcting the deviation from the approximate position.

[0050] 6 shows a situation in which a worker W is standing within the monitoring range R of the distance sensor 36 of the transfer robot 30, and a temporarily placed object Ob is also placed therein. Due to the occurrence of occlusion by the worker W and the temporarily placed object Ob, an obstructed area Da is generated in which the distance sensor 36 cannot grasp the distance to an object registered in the map information.

[0051] In such a case, it is easily understood that there is a decrease in the accuracy of the self-location information calculated by the self-location calculation unit 33. Therefore, the self-location calculation unit 33 also calculates accuracy information about the certainty of the self-location information according to the matching situation between the map information and the distance information, for example, how many point landmarks and line landmarks have been matched.

[0052] Fig. 7 shows a situation in which another transport robot 30b comes to be present within the monitoring range R of the distance sensor 36 of the transport robot 30a in the situation of Fig. 4. Fig. 8 is a graph corresponding to Fig. 5 at that time. As shown in the figure, the distance information acquired by the transport robot 30a includes information regarding the position of the other transport robot 30b.

[0053] That is, by analyzing the distance information acquired by the transport robot 30a, it is possible to obtain information on the distance and direction of the other transport robot 30b from the transport robot 30a, and on the orientation of the transport robot 30b. Therefore, it is understood that the position including the orientation of the transport robot 30b can be calculated from the self-position information of the transport robot 30a and the distance information acquired by the transport robot 30a.

[0054] 9 shows a situation where the transport robot 30a is within the monitoring range Rb of the transport robot 30b and within the monitoring range Rc of the transport robot 30c. There are three types of information regarding the position of the transport robot 30a: (i) its own position information calculated by the transport robot 30a; (ii) information regarding the position of the transport robot 30a derived from its own position information calculated by the transport robot 30b and distance information of the transport robot 30b; (iii) information regarding the position of the transport robot 30a derived from its own position information calculated by the transport robot 30c and distance information of the transport robot 30c.

[0055] By integrating these pieces of information to calculate information about the position of the transport robot 30a, (i) it becomes possible to further improve accuracy compared to relying only on the self-position information calculated by the transport robot 30a. More specifically, it is possible to integrate these pieces of information and obtain an estimated value of the position as follows.

[0056] For example, for coordinate X, it is assumed that estimated values ​​X1 to X3 are obtained by the above (i) to (iii). The simple average of estimated values ​​X1 to X3 can be used as the integrated location estimate. Alternatively, the weighted average using weighting coefficients determined according to the respective accuracy information for estimated values ​​X1 to X3 can be used as the integrated location estimate.

[0057] Alternatively, for each of the estimated values ​​X1 to X3, a probability distribution function such as a normal distribution having a variance determined according to the respective accuracy information and a peak at each estimated value can be calculated, and the peak of the distribution function obtained by adding up these probability distribution functions can be used as the integrated position estimate. The same applies to the coordinate Y and the direction θ.

[0058] 9, the transport robot 30b is present within the monitoring range Ra of the transport robot 30a and within the monitoring range Rc of the transport robot 30c. Therefore, information on the position of the transport robot 30b can be calculated with improved accuracy based on information from the other transport robots 30a and 30c in a similar manner. In this way, it becomes possible to obtain information on the position of the transport robot with improved accuracy based on the mutual information between the transport robots.

[0059] <Control device operation> The characteristic operation of the transport system 1 based on the above-mentioned principle of the estimated position calculation will be described below with reference to the flow chart of Fig. 10. In the transport system 1, when the transport robot 30 is executing the transport operation, the flow shown in Fig. 10 is repeatedly executed in real time.

[0060] Step S1: In each of the transfer robots 30 of the transfer system 1, distance information is acquired by the distance sensor 36. In addition, the travel control unit 32 calculates odometry data.

[0061] Step S2: In each of the transfer robots 30 in the transfer system 1, the self-position calculation unit 33 calculates self-position information based on the distance information and the odometry data.

[0062] Step S3: In each transport robot 30 of the transport system 1, the unique state notification unit transmits unique information including distance information and self-position information, together with the identification information of the transport robot 30 itself stored in the slave memory unit 37, to the control device 10 via the slave communication unit 39.

[0063] Step S4: The unique state acquisition unit 13 of the control device 10 acquires, via the master communication unit 19, unique information to which identification information is attached from each of the transfer robots 30.

[0064] Step S5: The positional relationship calculation unit 14 of the control device 10 calculates the monitoring range R of each transport robot 30 from the self-position information of each transport robot 30 included in the unique information. At this time, each transport robot 30 is identified based on the identification information of the transport robot 30 attached to the unique information. Furthermore, the positional relationship calculation unit 14 calculates which other transport robot 30 each transport robot 30 is within its monitoring range R based on each self-position information and each calculated monitoring range R.

[0065] Step S6: The estimated position calculation unit 15 of the control device 10 calculates estimated position information on the position of each transport robot 30. At this time, the estimated position calculation unit 15 uses the self-position information acquired from the transport robot 30, information on the position of the transport robot included in the distance information acquired from the transport robots 30 other than the transport robot 30, and the self-position information acquired from the transport robots 30 other than the transport robot 30. The calculation of the estimated position information is performed based on the method of calculating the "integrated position estimate" described in the above principle of estimated position calculation.

[0066] Step S7: The estimated position transmission unit 16 of the control device 10 transmits the estimated position information of each transport robot 30 calculated by the estimated position calculation unit 15 to each transport robot 30 via the master communication unit 19. At that time, the estimated position transmission unit 16 identifies each transport robot 30 based on the acquired identification information of the transport robot 30.

[0067] Step S8: In each of the transport robots 30 in the transport system 1, the estimated position acquisition unit 35 acquires the estimated position information of the own robot from the control device 10 through the slave communication unit 39. The estimated position acquisition unit 35 updates the information on the position of the own robot based on the acquired estimated position information.

[0068] According to the transport system 1 according to the configuration example, the position estimation of the transport robot 30 is performed based not only on the distance information from its own distance sensor 36, but also on the distance information from the distance sensors 36 of the other devices. Therefore, the accuracy of the position estimation of the transport robot 30 can be improved compared to the case where the position estimation is performed based only on the distance information from its own distance sensor 36.

[0069] [Software implementation example] Each functional block of the control device 10 (particularly, the higher-level command receiving unit 11, the instruction issuing unit 12, the inherent state acquisition unit 13, the positional relationship calculation unit 14, the estimated position calculation unit 15, and the estimated position transmission unit 16) or the functional blocks of the transport robot 30 (particularly, the instruction receiving unit 31, the driving control unit 32, the self-position calculation unit 33, the inherent state notification unit 34, and the estimated position acquisition unit 35) may be realized by a logic circuit (hardware) formed in an integrated circuit (IC chip) or the like, or may be realized by software.

[0070] In the latter case, the control device 10 or the transport robot 30 includes a computer that executes instructions of a program, which is software that realizes each function. This computer includes, for example, one or more processors, and a computer-readable recording medium that stores the program. In the computer, the processor reads the program from the recording medium and executes it, thereby achieving the object of the present invention.

[0071] The processor may be, for example, a CPU (Central Processing Unit). The recording medium may be a "non-transitory tangible medium" such as a ROM (Read Only Memory), a tape, a disk, a card, a semiconductor memory, a programmable logic circuit, or the like. The device may further include a RAM (Random Access Memory) for expanding the program.

[0072] The program may be supplied to the computer via any transmission medium capable of transmitting the program (such as a communication network or a broadcast wave). Note that one aspect of the present invention may also be realized in the form of a data signal embedded in a carrier wave, in which the program is embodied by electronic transmission.

[0073] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the disclosed technical means are also included in the technical scope of the present invention. [Explanation of symbols]

[0074] 1. Transport system 10 Control device 11. Upper Command Reception Department 12 Instructions Issuance Department 13 Eigenstate acquisition unit 14 Positional relationship calculation section 15 Estimated position calculation section 16 Estimated position transmission unit 17 Master Storage Unit 18 Upper communication section 19 Master communication unit 30, 30a-30c, 30M Transport robot 31 Instruction Reception Department 32 Driving control unit 33 Self-position calculation section 34 Eigenstate notification unit 35 Estimated position acquisition unit 36 Distance Sensor 37 Slave Memory Unit 38 Travel mechanism 39 Slave communication unit R, Ra~Rc monitoring range

Claims

1. A plurality of self-propelled transport robots; a control device that communicates with the plurality of transport robots; the transport robot has a sensor that detects a distance to a surrounding object and outputs the distance information, and a self-position calculation unit that calculates self-position information regarding a position of the transport robot itself using the distance information; The control device includes: an inherent state acquisition unit that acquires the self-position information and the distance information from each of the plurality of transport robots; an estimated position calculation unit that calculates estimated position information regarding the position of the transport robot using the self-position information acquired from the transport robot and information regarding the position of the transport robot included in the distance information acquired from a transport robot other than the transport robot; and an estimated position transmitting unit that notifies the transport robot of the estimated position of the transport robot.

2. The estimated position calculation unit The transport system according to claim 1 , wherein the estimated position information is calculated by also using the self-position information acquired from transport robots other than the transport robot in question.

3. 3. The transport system according to claim 1, wherein the self-position information and the estimated position information each include information on a position on a floor surface where the transport robot is traveling and information on a direction of the transport robot.

4. The transport robot further comprises: A traveling mechanism for performing traveling; a travel control unit that controls the travel mechanism unit and calculates odometry data of the transport robot, The self-position calculation unit is The transportation system according to claim 1 , wherein the self-position information is calculated based on the odometry data and the distance information.

5. The transport robot further comprises: A slave storage unit that stores identification information of the transport robot; a unique state notification unit that transmits unique information including the distance information and the self-location information by attaching the unique information to the identification information, The transport system according to claim 1 , wherein the specific state acquisition unit further acquires the identification information from a plurality of the transport robots.

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