JPWO2019054209A1 - Map making system and map making device - Google Patents

Abstract

The map creation system (101, 200) is fixedly installed in the space where the moving body moves, and a fixed sensor (103) that senses a part of the space at a plurality of different times and outputs sensor data at each time. And a map creation device (105) that receives sensor data at each time and creates a map of at least a part of the space. The sensor data (231, 223) at each time indicates the position of an object (221, 223) existing in a part of the space at each time. The map creation device (105) is a storage device (107) that stores sensor data at each time, and a map of a part of the space based on the position of a fixed object that is commonly included in all the sensor data at each time. It has a signal processing circuit (109) that creates certain local map data.

Description

The present disclosure relates to a map making system and a map making device.

Autonomous mobile robots that autonomously move in space along a predetermined path have been developed. The autonomous mobile robot senses the surrounding space using an external sensor such as a laser distance sensor, matches the sensing result with a map prepared in advance, and estimates (identifies) its current position and posture. .. The autonomous mobile robot can move along the path while controlling its current position and posture.

Japanese Unexamined Patent Publication No. 2005-326944 and Japanese Patent Application Laid-Open No. 2014-509417 disclose a map making technique used for matching. In each case, the laser distance sensor or the laser scanner is moved to scan the surrounding area and create a map of the scanned area. Objects that were in the area at the time the scan was performed are reflected on the map.

Japanese Unexamined Patent Publication No. 2005-326944 Japanese Patent Publication No. 2014-509417

The created map may reflect moving objects such as luggage. If the moving object is removed when the robot performs matching using such a map, the sensing result of the robot and the map may differ, and the estimation accuracy of the position and the posture may decrease.

An exemplary, but not limited, embodiment of the present application provides a technique for creating a map in which a moving object is referenced to estimate its position, taking into account the presence of moving objects.

The exemplary map-making system according to the present disclosure is a map-making system that creates a map that a moving body refers to in order to estimate its own position, and is fixedly installed in a space in which the moving body moves, and a plurality of maps are created. A fixed sensor that senses a part of the space at different times and outputs sensor data at each time, and a map creation device that receives the sensor data at each time and creates a map of at least a part of the space. The sensor data at each time indicates the position of an object existing in a part of the space at each time, and the map-making device includes a storage device for storing the sensor data at each time. It is provided with a signal processing circuit that creates local map data that is a map of a part of the space based on the position of a fixed object that is commonly included in all the sensor data at each time.

The above-mentioned comprehensive or specific embodiment may be realized by a system, a method, an integrated circuit, a computer program, or a recording medium. Alternatively, it may be realized by any combination of systems, devices, methods, integrated circuits, computer programs, and recording media.

According to the mapping system according to the exemplary embodiment of the present invention, it is possible to create a map in which a moving body is referred to for estimating its own position in consideration of the existence of a moving object.

FIG. 1 is a block diagram showing a schematic configuration of a moving body according to an exemplary embodiment of the present disclosure. FIG. 2 is a diagram showing an outline of a control system for controlling the traveling of each AGV according to the present disclosure. FIG. 3 is a diagram showing an example of a moving space in which an AGV exists. FIG. 4A is a diagram showing an AGV and a tow truck before being connected. FIG. 4B is a diagram showing a connected AGV and a tow truck. FIG. 5 is an external view of an exemplary AGV according to the present embodiment. FIG. 6A is a diagram showing a first hardware configuration example of the AGV. FIG. 6B is a diagram showing a second hardware configuration example of the AGV. FIG. 7A is a diagram showing an AGV that generates a map while moving. FIG. 7B is a diagram showing an AGV that generates a map while moving. FIG. 7C is a diagram showing an AGV that generates a map while moving. FIG. 7D is a diagram showing an AGV that generates a map while moving. FIG. 7E is a diagram showing an AGV that generates a map while moving. FIG. 7F is a diagram schematically showing a part of the completed map. FIG. 8 is a diagram showing an example in which a map of one floor is configured by a plurality of partial maps. FIG. 9 is a diagram showing a hardware configuration example of the operation management device. FIG. 10 is a diagram schematically showing an example of the movement route of the AGV determined by the operation management device. FIG. 11A is a bird's-eye view of a moving space in which a plurality of fixed sensors are installed. FIG. 11B is a diagram showing a configuration example of a map creation system including a fixed sensor and a map creation device. FIG. 12 is a perspective view showing the appearance of a laser range finder, which is an example of a fixed sensor. FIG. 13 is a hardware block diagram showing an internal configuration of a laser range finder, which is an example of a fixed sensor. FIG. 14 is a diagram showing an object existing in the moving space and a fixed sensor including the object in the field of view. FIG. 15 is a diagram showing a local map including sensor data output from a fixed sensor during a certain period. FIG. 16 is a diagram showing an updated local map. FIG. 17 is a flowchart showing a processing procedure of the map creating device. FIG. 18 is a diagram showing the transition of sensor data output from the fixed sensor when a plurality of objects appear at different times and at different positions. FIG. 19 is a diagram showing an example of a local map showing a fixed object and a movable object in a distinguishable manner. FIG. 20 is a diagram showing a point cloud representing a fixed object whose existence frequency is equal to or higher than a threshold value. FIG. 21 is a diagram showing a grid map displayed in a darker color as the value of the frequency of existence increases. FIG. 22 is a flowchart showing a processing procedure of a map creating device for creating a map displaying a fixed object and a movable object.

<Terminology>
Before describing embodiments of the present disclosure, definitions of terms used herein will be described.

An "automated guided vehicle" (AGV) means an automated guided vehicle that manually or automatically loads luggage into the body, automatically travels to a designated location, and manually or automatically unloads. "Automated guided vehicles" include unmanned tow trucks and unmanned forklifts.

The term "unmanned" means that no person is required to steer the vehicle, and does not exclude automatic guided vehicles carrying "people (eg, those who load and unload luggage)".

An "unmanned towing vehicle" is an untracked vehicle that automatically travels to a designated place by towing a trolley that manually or automatically loads and unloads luggage.

An "unmanned forklift" is an unmanned aerial vehicle equipped with a mast that raises and lowers a fork for transferring luggage, automatically transfers the luggage to the fork, etc., and automatically travels to a designated place to perform automatic cargo handling work.

A "trackless vehicle" is a vehicle that includes wheels and an electric motor or engine that rotates the wheels.

A "moving body" is a device that carries a person or luggage to move, and includes a driving device such as a wheel, a two-legged or multi-legged walking device, or a propeller that generates a driving force (traction) for movement. The term "mobile" in the present disclosure includes mobile robots, service robots, and drones as well as automatic guided vehicles in the narrow sense.

"Automated driving" includes traveling based on a command of a computer operation management system to which an automatic guided vehicle is connected by communication, and autonomous driving by a control device provided in the automated guided vehicle. Autonomous traveling includes not only traveling of an automated guided vehicle toward a destination along a predetermined route, but also traveling of following a tracking target. Further, the automatic guided vehicle may temporarily perform manual traveling based on the instruction of the operator. "Automatic driving" generally includes both "guided" driving and "guideless" driving, but in the present disclosure it means "guideless" driving.

The "guide type" is a method in which derivatives are installed continuously or intermittently and an unmanned carrier is guided by using the derivatives.

The "guideless type" is a method of guiding without installing a derivative. The automatic guided vehicle according to the embodiment of the present disclosure includes a self-position estimation device and can travel in a guideless manner.

The "self-position estimation device" is a device that estimates the self-position on the environmental map based on the sensor data acquired by an external sensor such as a laser range finder.

The "outside world sensor" is a sensor that senses the external state of a moving body. External world sensors include, for example, a laser range finder (also called a range finder), a camera (or image sensor), a lidar (Light Detection and Ranging), a millimeter wave radar, and a magnetic sensor.

The "inner world sensor" is a sensor that senses the internal state of a moving body. Internal world sensors include, for example, rotary encoders (hereinafter, may be simply referred to as “encoders”), acceleration sensors, and angular acceleration sensors (eg, gyro sensors).

"SLAM" is an abbreviation for Simultaneous Localization and Mapping, which means that self-position estimation and environmental mapping are performed at the same time.

<Exemplary Embodiment>
Hereinafter, an example of the map creation device and the map creation system according to the present disclosure will be described with reference to the attached drawings. In addition, more detailed explanation than necessary may be omitted. For example, a detailed explanation of already well-known matters or a duplicate explanation for substantially the same configuration may be omitted. This is to avoid unnecessary redundancy of the following description and to facilitate the understanding of those skilled in the art. The inventors provide accompanying drawings and the following description for those skilled in the art to fully understand the present disclosure. These are not intended to limit the subject matter described in the claims.

FIG. 1 is a block diagram showing a schematic configuration of a map creation system according to an exemplary embodiment of the present disclosure.

The map creation system 101 is used to create a map that the moving body refers to to estimate its own position. The map creation system 101 includes one or more fixed sensors 103a, 103b, 103c and a map creation device 105.

The fixed sensors 103a, 103b, and 103c are fixedly installed at different positions in the space in which the moving body moves (hereinafter referred to as "moving space"). Each of the fixed sensors 103a, 103b, and 103c senses (scans) the surrounding space at periodic or random timings, and outputs scan data (sensor data) at each time. The sensor data at each time indicates the position of an object existing in a part of the moving space at each time.

The fixed sensors 103a, 103b, 103c are carried in and installed when a new map of the space in which the moving body moves is created or recreated, and are removed after the collection of data for map creation is completed. obtain. The fixed sensors 103a, 103b, 103c may be fixed at the time of acquiring the scan data.

The map creating device 105 receives sensor data at each time from each of the fixed sensors 103a, 103b, and 103c, and creates a map of at least a part of the moving space. This will be described more specifically.

The map creating device 105 includes a storage device 107, a signal processing circuit 109, and an interface device 111 that receives sensor data at each time output from each fixed sensor. The interface device 111 can be a wired or wireless communication terminal and / or a communication circuit.

In FIG. 1, it is assumed that the map creating device 105 receives the sensor data each time the sensor data at each time is output from each fixed sensor. However, after each fixed sensor 103 acquires the sensor data at each time, it may be stored in an internal storage device and later collectively transferred to the map creating device 105. The transfer may be performed via a wired or wireless communication line, or may be performed via a storage medium such as a memory card.

The storage device 107 stores sensor data at each time received from each fixed sensor via the interface device 111. Further, the storage device 107 may store the map data M of the entire moving space in advance. Further, the storage device 107 may acquire and store the scan data obtained by each scan from the AGV or the like that moves around while scanning the entire moving space in order to create the map data. It is possible to create a map of the entire moving space while matching the scan data obtained from the AGV or the like with the sensor data obtained from each fixed sensor at each time.

The signal processing circuit 109 uses the sensor data stored in the storage device 107 to perform the following processing for each fixed sensor. For convenience of explanation, the fixed sensor 103a will be described as an example, but the same applies to the other fixed sensors 103b and 103c.

The signal processing circuit 109 acquires a set SDa of sensor data output from the fixed sensor 103a and acquired at a plurality of different times from the storage device 107. The signal processing circuit 109 creates local map data based on the position of an object that is commonly included in all the sensor data at each time. The "object commonly included in all the sensor data at each time" referred to here means an object that did not move during the sensing period by the fixed sensor, and is hereinafter referred to as a "fixed object". A fixed object is typically a wall or pillar that exists in a moving space. Any object that has not moved during the sensing period by the fixed sensor 103a is included in the "fixed object" even if it is a baggage that can be moved.

According to the above processing, it is possible to create a local map that reflects the position of the fixed object at least with respect to the space sensed by each fixed sensor.

The signal processing circuit 109 may update the map data M of the storage device 107 by using the created local map data. The updated map data M is transmitted to, for example, the moving bodies 10a to 10d, and each moving body is referred to for estimating its own position.

In the above example, the set SDa of the sensor data acquired at a plurality of different times may include an object that is not included in all of the sensor data at each time but is included only in a part thereof. .. The object is hereinafter referred to as a "movable object". A movable object is typically a load that has been placed on the floor of the moving space and then moved or removed, or a new load placed on the floor of the moving space. Movable objects may also include moving AGVs and people.

The signal processing circuit 109 may create a local map showing only the position of the fixed object, or may create a local map showing the position of the fixed object and the position of the movable object in an identifiable manner. An example of the latter is to identifiable the position of a fixed object when the existence frequency (ratio) of each movable object existing in the sensor data acquired at a plurality of different times is equal to or higher than a predetermined value. Examples of distinguishable display modes are that the fixed object and the movable object are displayed with different characters or icons, that the fixed object is displayed in the darkest color, while the frequency (ratio) of each movable object becomes smaller. It may be displayed in a light color.

Hereinafter, a more specific example when the moving body is an automatic guided vehicle will be described. In this specification, an abbreviation may be used to describe an automatic guided vehicle as "AGV". The following description can be similarly applied to mobile objects other than AGVs, such as mobile robots, drones, and manned vehicles, as long as there is no contradiction.

(1) Basic configuration of the system FIG. 2 shows a basic configuration example of the exemplary mobile management system 100 according to the present disclosure. The mobile body management system 100 includes at least one AGV 10 and an operation management device 50 that manages the operation of the AGV 10. FIG. 2 also shows a terminal device 20 operated by the user 1.

The AGV10 is an automatic guided vehicle capable of "guideless" traveling that does not require a derivative such as a magnetic tape for traveling. The AGV 10 can perform self-position estimation and transmit the estimation result to the terminal device 20 and the operation management device 50. The AGV 10 can automatically travel in the moving space S according to a command from the operation management device 50. The AGV10 can also operate in a "tracking mode" that follows a person or other moving object to move.

The operation management device 50 is a computer system that tracks the position of each AGV10 and manages the traveling of each AGV10. The operation management device 50 may be a desktop PC, a notebook PC, and / or a server computer. The operation management device 50 communicates with each AGV 10 via the plurality of access points 2. For example, the operation management device 50 transmits data of the coordinates of the position where each AGV10 should go next to each AGV10. Each AGV 10 periodically transmits data indicating its position and orientation to the operation management device 50, for example, every 100 milliseconds. When the AGV 10 reaches the instructed position, the operation management device 50 further transmits the coordinate data of the position to be next. The AGV 10 can also travel in the moving space S in response to the operation of the user 1 input to the terminal device 20. An example of the terminal device 20 is a tablet computer. Typically, the traveling of the AGV 10 using the terminal device 20 is performed at the time of creating the map, and the traveling of the AGV 10 using the operation management device 50 is performed after the map is created.

FIG. 3 shows an example of the moving space S in which three AGVs 10a, 10b and 10c exist. It is assumed that both AGVs are traveling in the depth direction in the figure. The AGVs 10a and 10b are transporting the load placed on the top plate. The AGV10c follows the front AGV10b and travels. For convenience of explanation, reference numerals 10a, 10b and 10c have been added in FIG. 3, but hereinafter, they will be referred to as “AGV10”.

In addition to the method of transporting the luggage placed on the top plate, the AGV10 can also transport the luggage by using a towing trolley connected to itself. FIG. 4A shows the AGV 10 and the tow truck 5 before being connected. Casters are provided on each foot of the tow truck 5. The AGV 10 is mechanically connected to the towing carriage 5. FIG. 4B shows the connected AGV 10 and the tow truck 5. When the AGV 10 travels, the towing carriage 5 is towed by the AGV 10. By towing the towing trolley 5, the AGV 10 can carry the load mounted on the towing trolley 5.

The connection method between the AGV 10 and the towing carriage 5 is arbitrary. An example will be described here. A plate 6 is fixed to the top plate of the AGV 10. The tow truck 5 is provided with a guide 7 having a slit. The AGV 10 approaches the towing carriage 5 and inserts the plate 6 into the slit of the guide 7. When the insertion is completed, the AGV 10 penetrates the plate 6 and the guide 7 with an electromagnetic lock type pin (not shown) to lock the electromagnetic lock. As a result, the AGV 10 and the towing carriage 5 are physically connected.

See FIG. 2 again. Each AGV 10 and the terminal device 20 can be connected to each other on a one-to-one basis, for example, to perform communication conforming to the Bluetooth (registered trademark) standard. Each AGV 10 and the terminal device 20 can also perform Wi-Fi (registered trademark) compliant communication using one or a plurality of access points 2. The plurality of access points 2 are connected to each other via, for example, a switching hub 3. Two access points 2a and 2b are shown in FIG. The AGV10 is wirelessly connected to the access point 2a. The terminal device 20 is wirelessly connected to the access point 2b. The data transmitted by the AGV 10 is received by the access point 2a, transferred to the access point 2b via the switching hub 3, and transmitted from the access point 2b to the terminal device 20. Further, the data transmitted by the terminal device 20 is received by the access point 2b, transferred to the access point 2a via the switching hub 3, and transmitted from the access point 2a to the AGV10. As a result, bidirectional communication between the AGV 10 and the terminal device 20 is realized. The plurality of access points 2 are also connected to the operation management device 50 via the switching hub 3. As a result, bidirectional communication is also realized between the operation management device 50 and each AGV 10.

(2) Creation of environmental map A map in the moving space S is created so that the AGV10 can travel while estimating its own position. The AGV10 is equipped with a position estimation device and a laser range finder, and can create a map by using the output of the laser range finder.

The AGV10 shifts to the data acquisition mode by the operation of the user. In the data acquisition mode, the AGV 10 starts acquiring sensor data using the laser range finder. The laser range finder periodically emits a laser beam of, for example, infrared or visible light to the surroundings to scan the surrounding space S. The laser beam is reflected, for example, on the surface of a structure such as a wall or a pillar, or an object placed on the floor. The laser range finder receives the reflected light of the laser beam, calculates the distance to each reflection point, and outputs the measurement result data showing the position of each reflection point. The position of each reflection point reflects the arrival direction and distance of the reflected light. The measurement result data obtained by one scan is sometimes called "measurement data" or "sensor data".

The position estimation device stores the sensor data in the storage device. When the acquisition of the sensor data in the moving space S is completed, the sensor data stored in the storage device is transmitted to the external device. The external device is, for example, a computer having a signal processing processor and having a mapping program installed.

The signal processor of the external device superimposes the sensor data obtained for each scan. A map of the space S can be created by repeatedly performing the superposition process by the signal processing processor. The external device transmits the created map data to the AGV10. The AGV10 stores the created map data in an internal storage device. The external device may be the operation management device 50 or another device.

The map may be created by the AGV 10 instead of the external device. A circuit such as an AGV10 microcontroller unit (microcomputer) may perform the processing performed by the signal processing processor of the external device described above. When creating a map in AGV10, it is not necessary to transmit the accumulated sensor data to an external device. The data capacity of the sensor data is generally considered to be large. Since it is not necessary to transmit the sensor data to the external device, it is possible to avoid occupying the communication line.

The movement in the moving space S for acquiring the sensor data can be realized by the AGV 10 traveling according to the operation of the user. For example, the AGV 10 wirelessly receives a travel command from the user via the terminal device 20 instructing the user to move in each of the front, rear, left, and right directions. The AGV10 travels back and forth and left and right in the moving space S according to a traveling command to create a map. When the AGV 10 is connected to a control device such as a joystick by wire, the map may be created by traveling in the moving space S in front, back, left and right according to a control signal from the control device. Sensor data may be acquired by a person pushing a measuring trolley equipped with a laser range finder.

Although a plurality of AGVs 10 are shown in FIGS. 2 and 3, the number of AGVs may be one. When a plurality of AGVs 10 exist, the user 1 can use the terminal device 20 to select one AGV10 from the plurality of registered AGVs and have the user 1 create a map of the moving space S.

After the map is created, each AGV10 can automatically travel while estimating its own position using the map. The process of estimating the self-position will be described later.

(3) The configuration diagram 5 of the AGV is an external view of an exemplary AGV 10 according to the present embodiment. The AGV 10 has two drive wheels 11a and 11b, four casters 11c, 11d, 11e and 11f, a frame 12, a transfer table 13, a traveling control device 14, and a laser range finder 15. The two drive wheels 11a and 11b are provided on the right side and the left side of the AGV 10, respectively. The four casters 11c, 11d, 11e and 11f are arranged at the four corners of the AGV10. The AGV10 also has a plurality of motors connected to the two drive wheels 11a and 11b, but the plurality of motors are not shown in FIG. Further, FIG. 5 shows one drive wheel 11a and two casters 11c and 11e located on the right side of the AGV 10, and a caster 11f located on the left rear portion, but the left drive wheel 11b and the left front portion are shown. Caster 11d is not specified because it is hidden behind the frame 12. The four casters 11c, 11d, 11e and 11f can freely rotate. In the following description, the drive wheels 11a and the drive wheels 11b will also be referred to as wheels 11a and wheels 11b, respectively.

The travel control device 14 is a device that controls the operation of the AGV 10, and mainly includes an integrated circuit including a microcomputer (described later), electronic components, and a substrate on which they are mounted. The travel control device 14 performs data transmission / reception and preprocessing calculation with the terminal device 20 described above.

The laser range finder 15 is an optical device that measures the distance to a reflection point by emitting, for example, an infrared or visible light laser beam 15a and detecting the reflected light of the laser beam 15a. In the present embodiment, the laser range finder 15 of the AGV 10 is a pulsed laser beam, for example, in a space within a range of 135 degrees to the left and right (270 degrees in total) with reference to the front surface of the AGV 10 while changing the direction every 0.25 degrees. It emits 15a and detects the reflected light of each laser beam 15a. As a result, it is possible to obtain data on the distance to the reflection point in the direction determined by the angle of 1081 steps in total every 0.25 degrees. In the present embodiment, the scanning of the surrounding space performed by the laser range finder 15 is substantially parallel to the floor surface and is planar (two-dimensional). However, the laser range finder 15 may scan in the height direction.

Based on the position and orientation (orientation) of the AGV10 and the scan result of the laser range finder 15, the AGV10 can create a map of the space S. The map may reflect the placement of walls, pillars and other structures around the AGV, and objects placed on the floor. The map data is stored in a storage device provided in the AGV10.

Generally, the position and posture of the moving body is called a pose. The position and orientation of the moving body in the two-dimensional plane are represented by the position coordinates (x, y) in the XY Cartesian coordinate system and the angle θ with respect to the X axis. The position and posture of the AGV 10, that is, the pose (x, y, θ) may be simply referred to as “position” below.

The position of the reflection point as seen from the radiation position of the laser beam 15a can be represented using polar coordinates determined by the angle and distance. In this embodiment, the laser range finder 15 outputs sensor data expressed in polar coordinates. However, the laser range finder 15 may convert the position expressed in polar coordinates into orthogonal coordinates and output it.

Since the structure and operating principle of the laser range finder are known, further detailed description thereof will be omitted in this specification. Examples of objects that can be detected by the laser range finder 15 are people, luggage, shelves, and walls.

The laser range finder 15 is an example of an external sensor for sensing the surrounding space and acquiring sensor data. Other examples of such external sensors include image sensors and ultrasonic sensors.

The travel control device 14 can estimate its own current position by comparing the measurement result of the laser range finder 15 with the map data held by itself. The map data held may be map data created by another AGV10.

FIG. 6A shows a first hardware configuration example of the AGV10. FIG. 6A also shows a specific configuration of the travel control device 14.

The AGV 10 includes a travel control device 14, a laser range finder 15, two motors 16a and 16b, a drive device 17, wheels 11a and 11b, and two rotary encoders 18a and 18b.

The travel control device 14 includes a microcomputer 14a, a memory 14b, a storage device 14c, a communication circuit 14d, and a position estimation device 14e. The microcomputer 14a, the memory 14b, the storage device 14c, the communication circuit 14d, and the position estimation device 14e are connected by a communication bus 14f, and data can be exchanged with each other. The laser range finder 15 is also connected to the communication bus 14f via a communication interface (not shown), and transmits the measurement data as the measurement result to the microcomputer 14a, the position estimation device 14e and / or the memory 14b.

The microcomputer 14a is a processor or a control circuit (computer) that performs an operation for controlling the entire AGV 10 including the travel control device 14. Typically, the microcomputer 14a is a semiconductor integrated circuit. The microcomputer 14a transmits a PWM (Pulse Width Modulation) signal, which is a control signal, to the drive device 17 to control the drive device 17 and adjust the voltage applied to the motor. As a result, each of the motors 16a and 16b rotates at a desired rotation speed.

One or more control circuits (for example, a microcomputer) that control the drive of the left and right motors 16a and 16b may be provided independently of the microcomputer 14a. For example, the motor drive device 17 may include two microcomputers that control the drive of the motors 16a and 16b, respectively. The two microcomputers may perform coordinate calculation using the encoder information output from the encoders 18a and 18b, respectively, and estimate the moving distance of the AGV 10 from a given initial position. Further, the two microcomputers may control the motor drive circuits 17a and 17b by using the encoder information.

The memory 14b is a volatile storage device that stores a computer program executed by the microcomputer 14a. The memory 14b can also be used as a work memory when the microcomputer 14a and the position estimation device 14e perform calculations.

The storage device 14c is a non-volatile semiconductor memory device. However, the storage device 14c may be a magnetic recording medium typified by a hard disk or an optical recording medium typified by an optical disk. Further, the storage device 14c may include a head device for writing and / or reading data to any recording medium and a control device for the head device.

The storage device 14c stores the map data M of the traveling space S and the data (traveling route data) R of one or a plurality of traveling routes. The map data M is created by the AGV 10 operating in the map creation mode and stored in the storage device 14c. The travel route data R is transmitted from the outside after the map data M is created. In the present embodiment, the map data M and the travel route data R are stored in the same storage device 14c, but may be stored in different storage devices.

An example of the travel route data R will be described.

When the terminal device 20 is a tablet computer, the AGV 10 receives the travel route data R indicating the travel route from the tablet computer. The traveling route data R at this time includes marker data indicating the positions of a plurality of markers. The "marker" indicates a passing position (passage point) of the traveling AGV 10. The travel route data R includes at least the position information of the start marker indicating the travel start position and the end marker indicating the travel end position. The travel route data R may further include the position information of the markers of one or more intermediate waypoints. When the traveling route includes one or more intermediate waypoints, the route from the start marker to the end marker via the traveling waypoints in order is defined as the traveling route. The data of each marker may include, in addition to the coordinate data of the marker, data of the direction (angle) and the traveling speed of the AGV 10 until the movement to the next marker. When the AGV 10 temporarily stops at the position of each marker and performs self-position estimation and notification to the terminal device 20, the data of each marker is the acceleration time required for acceleration until the traveling speed is reached, and / or , The data of the deceleration time required for deceleration from the traveling speed to the stop at the position of the next marker may be included.

The operation management device 50 (for example, a PC and / or a server computer) may control the movement of the AGV 10 instead of the terminal device 20. In that case, the operation management device 50 may instruct the AGV 10 to move to the next marker each time the AGV 10 reaches the marker. For example, the AGV 10 receives from the operation management device 50 the coordinate data of the target position to be headed next, or the data of the distance to the target position and the angle to be traveled as the travel route data R indicating the travel route.

The AGV 10 can travel along the stored travel route while estimating its own position using the created map and the sensor data output by the laser range finder 15 acquired during travel.

The communication circuit 14d is, for example, a wireless communication circuit that performs wireless communication conforming to the Bluetooth (registered trademark) and / or Wi-Fi (registered trademark) standard. Both standards include wireless communication standards that utilize frequencies in the 2.4 GHz band. For example, in the mode in which the AGV 10 is run to create a map, the communication circuit 14d performs wireless communication conforming to the Bluetooth (registered trademark) standard and communicates with the terminal device 20 on a one-to-one basis.

The position estimation device 14e performs a map creation process and a self-position estimation process during traveling. The position estimation device 14e creates a map of the moving space S based on the position and orientation of the AGV 10 and the scan result of the laser range finder. During traveling, the position estimation device 14e receives the sensor data from the laser range finder 15 and reads out the map data M stored in the storage device 14c. By matching the local map data (sensor data) created from the scan results of the laser range finder 15 with the map data M in a wider range, the self-position (x, y, θ) on the map data M can be determined. To identify. The position estimation device 14e generates "reliability" data indicating the degree to which the local map data matches the map data M. The self-position (x, y, θ) and reliability data can be transmitted from the AGV 10 to the terminal device 20 or the operation management device 50. The terminal device 20 or the operation management device 50 can receive the self-position (x, y, θ) and reliability data and display them on the built-in or connected display device.

In the present embodiment, the microcomputer 14a and the position estimation device 14e are considered to be separate components, but this is an example. It may be one chip circuit or a semiconductor integrated circuit capable of independently performing each operation of the microcomputer 14a and the position estimation device 14e. FIG. 6A shows a chip circuit 14g including the microcomputer 14a and the position estimation device 14e. Hereinafter, an example in which the microcomputer 14a and the position estimation device 14e are provided separately and independently will be described.

The two motors 16a and 16b are attached to the two wheels 11a and 11b, respectively, to rotate each wheel. That is, the two wheels 11a and 11b are driving wheels, respectively. In the present specification, the motor 16a and the motor 16b are described as being motors for driving the right wheel and the left wheel of the AGV10, respectively.

The moving body 10 further includes an encoder unit 18 for measuring the rotation position or rotation speed of the wheels 11a and 11b. The encoder unit 18 includes a first rotary encoder 18a and a second rotary encoder 18b. The first rotary encoder 18a measures the rotation of the power transmission mechanism from the motor 16a to the wheels 11a at any position. The second rotary encoder 18b measures the rotation of the power transmission mechanism from the motor 16b to the wheels 11b at any position. The encoder unit 18 transmits the signals acquired by the rotary encoders 18a and 18b to the microcomputer 14a. The microcomputer 14a may control the movement of the moving body 10 by using not only the signal received from the position estimation device 14e but also the signal received from the encoder unit 18.

The drive device 17 has motor drive circuits 17a and 17b for adjusting the voltage applied to each of the two motors 16a and 16b. Each of the motor drive circuits 17a and 17b includes a so-called inverter circuit. The motor drive circuits 17a and 17b turn on or off the current flowing through each motor by the PWM signal transmitted from the microcomputer 14a or the microcomputer in the motor drive circuit 17a, thereby adjusting the voltage applied to the motor.

FIG. 6B shows a second hardware configuration example of the AGV10. The second hardware configuration example differs from the first hardware configuration example (FIG. 6A) in that it has a laser positioning system 14h and that the microcomputer 14a is connected to each component on a one-to-one basis. To do.

The laser positioning system 14h includes a position estimation device 14e and a laser range finder 15. The position estimation device 14e and the laser range finder 15 are connected by, for example, an Ethernet (registered trademark) cable. Each operation of the position estimation device 14e and the laser range finder 15 is as described above. The laser positioning system 14h outputs information indicating the pose (x, y, θ) of the AGV 10 to the microcomputer 14a.

The microcomputer 14a has various general-purpose I / O interfaces or general-purpose input / output ports (not shown). The microcomputer 14a is directly connected to other components in the travel control device 14, such as the communication circuit 14d and the laser positioning system 14h, via the general-purpose input / output port.

Except for the configuration described above with respect to FIG. 6B, the configuration is the same as that of FIG. 6A. Therefore, the description of the common configuration will be omitted.

The AGV 10 in the embodiment of the present disclosure may include a safety sensor such as a bumper switch (not shown). The AGV10 may include an inertial measurement unit such as a gyro sensor. By using the measurement data by the rotary encoders 18a and 18b or the internal sensor such as the inertial measurement unit, it is possible to estimate the movement distance and the change amount (angle) of the posture of the AGV10. These distance and angle estimates are called odometry data and can exert a function of assisting the position and orientation information obtained by the position estimation device 14e.

(4) Map data FIGS. 7A to 7F schematically show an AGV 10 moving while acquiring sensor data. The user 1 may manually move the AGV 10 while operating the terminal device 20. Alternatively, the unit including the travel control device 14 shown in FIGS. 6A and 6B, or the AGV10 itself may be placed on the trolley, and the user 1 may manually push or pull the trolley to acquire sensor data.

FIG. 7A shows an AGV 10 that scans the surrounding space using the laser range finder 15. A laser beam is emitted at a predetermined step angle to perform scanning. The illustrated scan range is an example schematically shown, and is different from the above-mentioned scan range of 270 degrees in total.

In each of FIGS. 7A to 7F, the positions of the reflection points of the laser beam are schematically shown by using a plurality of black points 4 represented by the symbol “•”. The laser beam scan is performed at short intervals while the position and orientation of the laser range finder 15 changes. Therefore, the actual number of reflection points is much larger than the number of reflection points 4 shown in the figure. The position estimation device 14e stores the positions of the black spots 4 obtained during traveling, for example, in the memory 14b. The map data is gradually completed by continuously scanning while the AGV10 is running. In FIGS. 7B-7E, only the scan range is shown for brevity. The scan range is an example and is different from the above-mentioned example of total 270 degrees.

The map may be created by using the microcomputer 14a in the AGV10 or an external computer based on the sensor data after acquiring the amount of sensor data required for map creation. Alternatively, a map may be created in real time based on the sensor data acquired by the moving AGV10.

FIG. 7F schematically shows a part of the completed map 40. In the map shown in FIG. 7F, the free space is partitioned by a point cloud corresponding to a collection of reflection points of the laser beam. Another example of a map is an occupied grid map that distinguishes between the space occupied by an object and the free space on a grid-by-grid basis. The position estimation device 14e stores map data (map data M) in the memory 14b or the storage device 14c. The number or density of sunspots shown is an example.

The map data thus obtained can be shared by a plurality of AGV10s.

A typical example of an algorithm in which the AGV10 estimates its own position based on map data is ICP (Iterative Closest Point) matching. As described above, by matching the local map data (sensor data) created from the scan result of the laser range finder 15 with the map data M in a wider range, the self-position (x,) on the map data M is performed. y, θ) can be estimated.

When the area in which the AGV 10 travels is wide, the amount of map data M increases. Therefore, inconveniences such as an increase in map creation time and a large amount of time required for self-position estimation may occur. When such an inconvenience occurs, the map data M may be created and recorded separately for a plurality of partial map data.

FIG. 8 shows an example in which the entire area of one floor of one factory is covered by the combination of the four partial map data M1, M2, M3, and M4. In this example, one partial map data covers an area of 50m x 50m. A rectangular overlapping area having a width of 5 m is provided at the boundary between two adjacent maps in each of the X and Y directions. This overlapping area is called a "map switching area". When the AGV 10 traveling while referring to one partial map reaches the map switching area, it switches to traveling referring to another adjacent partial map. The number of partial maps is not limited to four, and may be appropriately set according to the area of the floor on which the AGV10 travels, the performance of the computer that performs map creation and self-position estimation. The size of the partial map data and the width of the overlapping area are not limited to the above example, and may be set arbitrarily.

(5) Configuration Example of Operation Management Device FIG. 9 shows a hardware configuration example of the operation management device 50. The operation management device 50 includes a CPU 51, a memory 52, a position database (position DB) 53, a communication circuit 54, a map database (map DB) 55, and an image processing circuit 56.

The CPU 51, the memory 52, the position DB 53, the communication circuit 54, the map DB 55, and the image processing circuit 56 are connected by a communication bus 57, and data can be exchanged with each other.

The CPU 51 is a signal processing circuit (computer) that controls the operation of the operation management device 50. Typically, the CPU 51 is a semiconductor integrated circuit.

The memory 52 is a volatile storage device that stores a computer program executed by the CPU 51. The memory 52 can also be used as a work memory when the CPU 51 performs an operation.

The position DB 53 stores position data indicating each position that can be a destination of each AGV 10. Location data can be represented, for example, by coordinates virtually set within the factory by the administrator. Location data is determined by the administrator.

The communication circuit 54 performs wired communication conforming to, for example, an Ethernet (registered trademark) standard. The communication circuit 54 is connected to the access point 2 (FIG. 1) by wire, and can communicate with the AGV 10 via the access point 2. The communication circuit 54 receives data to be transmitted to the AGV 10 from the CPU 51 via the bus 57. Further, the communication circuit 54 transmits the data (notification) received from the AGV 10 to the CPU 51 and / or the memory 52 via the bus 57.

The map DB 55 stores map data of the inside of a factory or the like on which the AGV 10 runs. The map may be the same as or different from the map 40 (FIG. 7F). The data format does not matter as long as the map has a one-to-one correspondence with the position of each AGV10. For example, the map stored in the map DB 55 may be a map created by CAD.

The position DB 53 and the map DB 55 may be built on a non-volatile semiconductor memory, a magnetic recording medium typified by a hard disk, or an optical recording medium typified by an optical disk.

The image processing circuit 56 is a circuit that generates video data to be displayed on the monitor 58. The image processing circuit 56 operates exclusively when the administrator operates the operation management device 50. In this embodiment, further detailed description will be omitted. The monitor 59 may be integrated with the operation management device 50. Further, the CPU 51 may perform the processing of the image processing circuit 56.

(6) Operation of the Operation Management Device The outline of the operation of the operation management device 50 will be described with reference to FIG. FIG. 10 is a diagram schematically showing an example of the movement route of the AGV 10 determined by the operation management device 50.

The outline of the operation of the AGV 10 and the operation management device 50 is as follows. In the following, an example will be described in which a certain AGV 10 is currently in the position M ₁ , passes through several positions, and travels to the final destination position M _{n + 1} (a positive integer greater than or equal to n: 1). .. In the position DB 53, coordinate data indicating each position such as the position M ₂ to be passed next to the position M _{1 and} the position M ₃ to be passed next to the position M ₂ is recorded.

The CPU 51 of the operation management device 50 reads out the coordinate data of the position M ₂ with reference to the position DB 53, and generates a travel command for the position M ₂ . The communication circuit 54 transmits a travel command to the AGV 10 via the access point 2.

The CPU 51 periodically receives data indicating the current position and posture from the AGV 10 via the access point 2. In this way, the operation management device 50 can track the position of each AGV 10. CPU51 determines that the current position of the AGV10 matches the position _{M 2,} reads the coordinate data of the position _{M 3,} and transmits the AGV10 generates a travel command to direct the position _{M 3.} That is, when the operation management device 50 determines that the AGV 10 has reached a certain position, it transmits a travel command to move to the position to be passed next. As a result, the AGV ₁₀ can reach the final target position M _{n + 1} . The above-mentioned passing position and target position of AGV10 may be referred to as "markers".

(7) Details of Map Creation System Next, a more specific example of the map creation system 200 according to the present embodiment will be described.

FIG. 11A is a bird's-eye view of the moving space S in which a plurality of fixed sensors 103 are installed. Further, FIG. 11B shows a configuration example of the map creation system 200 including the fixed sensor 103 and the map creation device 105. The map creating device 105 is connected to the access point 2 and the operation management device 50 via the hub 3.

Each fixed sensor 103 is fixedly installed in the moving space S, and at a plurality of different times, a part of the moving space S included in the field of view of each fixed sensor 103 is sensed to obtain sensor data at each time. It is wirelessly output to the map creation device 105.

As the fixed sensor 103, the above-mentioned "outside sensor" can be used. An example of the fixed sensor 103 is a laser range finder. Now, suppose that the fixed sensor 103 starts scanning at time T and outputs data on the position of the reflection point in a direction determined by an angle of 1081 steps in total every 0.25 degrees. The output data is a point cloud (Point Cloud) corresponding to a collection of reflection points of the laser beam. The set of these data is called "sensor data at time T". The maximum number of sensor data at time T is 1081. If the reflected light does not come back, the number of sensor data will be less than 1081.

Placing the fixed sensor 103 "fixedly" in the moving space S means that the position and angle (posture) of each fixed sensor 103 do not change, at least during scanning. The fixed sensor 103 does not have to be firmly fixed to the floor surface as long as the position and posture do not change. For example, the laser range finder 15 built in the stationary AGV 10 may be used as the fixed sensor 103.

The access point 2 receives the radio signal of the sensor data of each time output from each fixed sensor 103, and transmits the received sensor data to the map creating device 105 via the hub 3.

The map creation device 105 is a local map which is a partial map (local map) of the moving space S based on the position of the fixed object which is commonly included in all the sensor data of each time output from each fixed sensor 103. Create data. The map creation device 105 updates the map of the moving space S using the local map. When the map creation device 105 transmits the updated map of the moving space S to the operation management device 50, the operation management device 50 updates the map managed by itself with the received map. The operation management device 50 transmits, for example, an updated map to one or a plurality of AGVs managed by the operation management device 50. This allows each AGV to estimate its own position with reference to the latest map.

Unless otherwise specified, of the configurations shown in FIG. 11B, the same configurations as those in FIG. 2 are designated by the same reference numerals, and the description thereof will be omitted.

12 and 13 are a perspective view showing the appearance of the laser range finder, which is an example of the fixed sensor 103, and a hardware block view showing the internal configuration. See FIG. The fixed sensor 103 includes a CPU 201, a memory 203, a communication circuit 205, a drive circuit 207, and a laser device 209.

The CPU 201 is a semiconductor integrated circuit that controls the operation of the fixed sensor 103. The memory 203 is a storage device that temporarily stores the acquired sensor data. The communication circuit 205 transmits sensor data by wireless communication conforming to the Wi-Fi (registered trademark) standard. The drive circuit 207 generates a drive current to be passed through the laser device 209 according to a control signal from the CPU 201. The laser device 209 emits an infrared or visible light laser beam 15b based on the supplied drive current. Further, the laser device 209 has a light detector (not shown), and detects the reflected light of the emitted laser beam 15b.

The CPU 201 generates a control signal for instructing the timing of passing a current through the drive circuit 207 and the current value, and drives the drive circuit 207 by the control signal. Further, the CPU 201 calculates the distance to the reflection point by using the difference between the phase of the emitted laser beam 15b and the phase of the reflected light acquired by the photodetector of the laser device 209. Since the method of calculating the distance is well known, the description in this specification is omitted. The frequency of the laser beam 15b does not have to be one, but may be plural. The direction in which the reflected light of the laser beam 15b arrives represents the direction in which the object exists as seen from the fixed sensor 103.

The configuration of the laser range finder 15 (FIGS. 6A, 6B, etc.) is also the same as that of the fixed sensor 103 described above.

FIG. 14 shows objects 221 and 223 existing in the moving space S, and fixed sensors 103p to 103s including the objects 221 or 223 in the field of view. For convenience of understanding, the field of view of each fixed sensor 103p to 103s is indicated by a fan shape centered on each fixed sensor. The radius of the sector corresponds to the detectable distance of each fixed sensor, but the size of the radius of the sector shown is only an example.

In the example of FIG. 14, the fixed sensor 103p detects the object 221 and the fixed sensor 103q-103s detects the object 223. For example, the fixed sensor 103p can detect the orientation in which the object 221 exists and the distance to the object 221. The same applies to the fixed sensors 103q to 103s.

FIG. 15 shows a local map 41 including sensor data output from each fixed sensor 103p-103s during a period of time. Point clouds that do not exist in the previously obtained overall map and appear specifically in the sensor data are surrounded by alternate long and short dash lines 231 and 233. The point groups in the ellipse of the alternate long and short dash lines 231 and 233 are candidates for movable objects.

In the present embodiment, the sensor data in the alternate long and short dash line 231 is a set (point group) of reflection points output from the fixed sensor 103p, and indicates the position of the object 221. The sensor data in the alternate long and short dash line 233 is a set (point group) of reflection points output from the fixed sensor 103q to 103s, and indicates the position of the object 223.

Now, it is assumed that each fixed sensor 103p to 103s performs sensing once every hour for 24 hours. Then, consider an example in which the local map 41 is obtained in the first 8 hours, the local map 40 (FIG. 7F) is obtained in the next 8 hours, and the local map 41 is obtained again in the remaining 8 hours. In the case of this example, the objects 221 and 223 are "movable objects" because they are not included in all of the sensor data at each time, but are included in only a part of them.

In the present embodiment, when the local maps 40 and 41 are obtained by using a plurality of fixed sensors 103 including the fixed sensors 103p to 103s, the local map 40 is reflected in the entire map of the moving space S. That is, the position of the movable object is not reflected on the map of the moving space S, and only the position of the fixed object is reflected on the entire map of the moving space S.

Therefore, when the previously obtained overall map includes the local map 41, the map creation device 105 updates the local map 41 to the local map 40 that does not include the moving object. FIG. 16 shows the updated local map 40. It is understood that there is no sensor data in the area surrounded by the alternate long and short dash lines 241 and 243 of the local map 40, and the movable objects 221 and 223 included in the local map 41 (FIG. 15) are not reflected. To.

On the other hand, when the previously obtained overall map includes the local map 40, the map creation device 105 maintains the local map 40 without updating it even if the local map 41 is obtained later.

The above-mentioned specific example will be generalized and described. FIG. 17 is a flowchart showing a processing procedure of the map creating device 105.

First, one or more fixed sensors 103 sense a part (subspace) of the moving space S at time _Tn (n: 1, ..., N; N is an integer of 2 or more), and at each time. Output sensor data. The series of time T _n may be periodic or random. Case of installing a plurality of fixed sensors, each of the fixed sensors need not simultaneously perform sensing at time T _n. It suffices if the map creating device 105 can process using the sensor data received from each fixed sensor within a predetermined period.

In step S10, the map creation device 105 receives the sensor data at each time _{T n} from the fixed sensor. The signal processing circuit 109 stores the received sensor data in the storage device 107.

In step S11, the signal processing circuit 109, an object appearing in the sensor data for all time of the sensor data at time T _N from the time T ₁ is determined to be a stationary object, appears at the sensor data in some time only The object is determined to be a movable object. The signal processing circuit 109 can determine, for example, an object represented by the data obtained by calculating the logical product of the sensor data from the time T ₁ to the time _TN as a fixed object. The basis for this calculation is that the position and orientation of the fixed sensor 103 do not change, so that the position of the fixed object does not substantially change in the obtained sensor data.

On the other hand, the signal processing circuit 109 determines that the object appearing in the data obtained by calculating the negative product of the above-mentioned logical product and the logical product of each sensor data from time T ₁ to time _TN is a movable object. be able to.

In step S12, the signal processing circuit 109 creates a local map based on the position of the fixed object. Since the data obtained by the calculation result of the above-mentioned logical product represents the position of the fixed object, the signal processing circuit 109 can create a local map using the calculation result. If the created local map already matches a part of the whole map, the map is not updated. If it does not match, the corresponding part of the whole map may be updated to the created local map. ..

In the process of step S11 described above, there is a possibility that a fixed object existing behind the movable object is determined as a movable object. The laser beam of the fixed sensor was blocked by a moving object, but when the moving object is removed, the laser beam reaches the fixed object that was behind it. The set of reflection points (point cloud) of the laser beam reflects the position of the fixed object, but it does not exist in the sensor data of all the time T ₁ to time _TN obtained so far. .. As a result, the fixed object can be mistaken for a newly placed moving object.

The following methods can be considered to avoid misidentification. Consider a case where a fixed sensor 103 outputs sensor data at time t1 and t2 (t1 <t2), respectively, and the two sensor data do not match each other.

First example: If the movable object was present at time t1 but was removed at time t2, the two sensor data do not match. At this time, at time t1, a point cloud representing a movable object exists at a position relatively close to the fixed sensor 103, and at time t2, a newly detected point cloud exists at a position relatively far from the fixed sensor 103.

Second example: The movable object did not exist at time t1, but the two sensor data do not match even when it is newly placed at time t2. At this time, at time t1, a point cloud exists at a position relatively far from the fixed sensor 103, but at time t2, a newly detected point group representing a movable object appears at a position relatively close to it. ..

From the first and second examples, when two sensor data sensed by a fixed sensor 103 at different times do not match, the point cloud at a relatively distant position is actually fixed, such as a wall. It is likely to represent an object that is an object. Therefore, in the case of the first example, the sensor data after the time t2 is further used to determine whether or not the point group at a relatively distant position continues to exist at the same position, and the point group exists at the same position. If so, it can be determined that the point group is a fixed object. In the case of the second example, the sensor data before the time t1 is further used to determine whether or not the point group at a relatively distant position has existed at the same position from before, and the point group exists at the same position. If so, it can be determined that the point group is a fixed object.

FIG. 18 shows the transition of the sensor data output from the fixed sensor 103 when a plurality of objects appear at different times and at different positions. The example shown in FIG. 18 is an example based on sensor data output from all fixed sensors including the fixed sensor 103p to 103s (FIG. 14). Further, it is assumed that the entire map of the moving space S is prepared in advance.

The sensor data 251 exists during the entire period from time t = 1 to _TN . Therefore, the object represented by the sensor data 251 is a "fixed object".

On the other hand, the sensor data 253 exists only at time t = Tk and Tk + 1, and the sensor data 255 exists only at time t = Tk + m. Therefore, the sensor data 253 and 255 are "movable objects".

The signal processing circuit 109 of the map creating device 105 calculates the logical product of the sensor data at the time _TN from the time T ₁ to obtain the sensor data indicated at the time t = T ₁ or _TN . The signal processing circuit 109 reflects the obtained map data in a part of the entire map of the moving space S.

Next, an example of a process of creating a local map reflecting the position of a movable object will be described with reference to FIGS. 19 to 22. The determination process of the movable object and the fixed object is based on the above example.

FIG. 19 shows an example of a local map 42 showing a fixed object and a movable object in a distinguishable manner. In the example of FIG. 19, the position of a fixed object such as a wall is represented by a set of dots 261 indicated by “•”. On the other hand, the position of the movable object is represented by a set of marks 263 indicated by "X" (see the circle of the alternate long and short dash line).

By indicating the position of the movable object with a character different from the character of the fixed object, the operation management device 50 or a person can easily recognize the position of the movable object and determine the traveling route. Alternatively, since the administrator can easily recognize the position where a movable object such as a luggage is likely to be placed, the position where the luggage is temporarily placed can be adjusted so as not to interfere with the running of the AGV10. This makes it easier to improve the working environment of people and AGV10.

In addition to changing the character of the fixed object and the character of the moving object, the two may be distinguished by different icons and characters indicating the fixed object and the moving object, respectively.

Further, the position of the movable object having a certain period of existence or more is displayed on the local map, and the position of the movable object having an existence period of less than a certain period is not displayed on the local map. Good. Now, once we obtained point group in the scan at time T _k is referred to as one scan data or one sensor data. It is assumed that K (an integer of K: 1 or more and less than N) of the N scan data obtained at each time from time T ₁ to time _TN includes a point cloud of a movable object. Hereinafter, the value K is referred to as the "presence frequency" of the sensor data of the moving object. It can be said that the existence frequency is the ratio of the scan data including the point group of the moving object to the N scan data.

The signal processing circuit 109 identifiablely displays the position of the movable object on the local map when the value of the existence frequency K is equal to or greater than the threshold value. The threshold value may be represented by a fixed value, or may be represented by, for example, a value that varies depending on the ratio according to the total number of scans N. In the latter example, the threshold = N / 3.

Now, it is assumed that the point groups of the alternate long and short dash lines 231 and 233 shown in FIG. 15 are obtained. Each point group represents the position of a movable object. It is assumed that the existence frequency of the fixed object corresponding to the point group in the alternate long and short dash line 231 is equal to or higher than the threshold value, and the existence frequency of the fixed object corresponding to the point group in the alternate long and short dash line 233 is less than the threshold value. The local map at this time is shown in FIG. The local map 43 includes a point group within the alternate long and short dash line 231 indicating the position of the movable object whose existence frequency is equal to or higher than the threshold value, but indicates the position of the movable object whose existence frequency is less than the threshold value within the alternate long and short dash line 233. Does not include the point group of.

Further, the concept of the existence frequency K can be extended to the entire moving space S to create a local map or a map attached to the local map. The value of the existence frequency K of the point group of the fixed object existing in the moving space S is K = N. The value of the existence frequency K of the point group of the movable object is an integer value of 1 or more and less than N. Further, the value of the existence frequency K of the point cloud relating to the space where no object exists, that is, the free space such as the passage where the AGV10 can travel is K = 0.

FIG. 21 shows a grid map 44 that is displayed darker as the value of the existence frequency K is larger. For convenience of description, the difference in color is represented by the difference in pattern, but it is possible to change the density on a gray scale, for example. The signal processing circuit 109 creates a grid map 44 by dividing the moving space S in a grid pattern, determining a representative K for each square, and representing the squares with a density corresponding to the value of K. .. In the grid map 44 according to the present embodiment, the passage (free space) in which the AGV 10 can travel is expressed in white, and the position where the non-travelable fixed object exists is displayed in a darker color than white. The squares where the movable object exists for a long time are displayed in a darker color. According to the grid map 44, even if the grid is not white, it can be determined that the path is less affected by the moving object if the density is low. Instead of the gray scale, it may be represented by a color corresponding to the value of the existence frequency K.

The grid map 44 may be created separately from the local map, or may be created as attribute information attached to the local map. When associated with the local map as attribute information, the AGV10 can also use the value of the existence frequency K as the "weight" of the position corresponding to each square. For example, it can be considered that a fixed object or an object similar to a fixed object exists in the area of the square where the value of the existence frequency K is large (the weight is large). On the other hand, the area of the square where the value of the existence frequency K is small (the weight is small) is a passage that can be traveled, or a passage where a movable object exists but the existence frequency is small, so that the influence on traveling is small. It can be regarded as being. The AGV10 may select a route with a small weight. In addition, for example, by using the reciprocal of the existence frequency K, the weight may be increased as the area of the square having a smaller influence on running.

According to the above processing, it is possible to create or maintain a map that is not affected by the moving object or a map that shows the magnitude of the influence of the moving object.

FIG. 22 is a flowchart showing a processing procedure of the map creation device 105 for creating a map displaying a fixed object and a movable object. Since the process from the start of the process to step S11 is the same as the procedure of the process of FIG. 17, the description thereof will be omitted again.

In step S13, the signal processing circuit 109 creates a local map in which a fixed object and a movable object are identifiablely displayed according to the determination result in step S11. Identification of a fixed object or a movable object can be realized by differentiating a character, an icon, a character, an existence frequency, a concentration according to the existence frequency, and the like.

In the above description, the installation position of the fixed sensor 103 is not particularly mentioned. However, if it is installed at a position where there are relatively many movable objects, the local map reflecting the movable objects can be updated more quickly.

Whether the region has a relatively large number of movable objects or a region with a relatively small number of movable objects can be known from the degree of matching when the AGV 10 actually travels and matches the sensor data and the map data. As described above, the position estimation device 14e of the AGV10 generates "reliability" data indicating the degree to which the local map data matches the map data M. When the AGV 10 is actually run, it can be estimated that the lower the reliability of the position or region, the more movable objects there are.

When the mobile body management system 100 is introduced, the AGV 10 is run in an environment where it is actually used, and a log of reliability data is stored in the storage device of the AGV 10. Later, the logs may be analyzed and one or more fixed sensors 103 may be installed to have a field of view that includes a position or region whose reliability is below a predetermined threshold.

In the above-described embodiment, the map creation device 105 is provided separately from the AGV 10 and the operation management device 50, but the microcomputer, CPU, etc. inside the AGV 10 or the operation management device 50 operate the map creation device 105. You may do it.

In the description of the above-described embodiment, an AGV traveling in a two-dimensional space (floor surface) is given as an example. However, the present disclosure may also apply to moving objects moving in three-dimensional space, such as flying objects (drones). When a drone creates a three-dimensional space map while flying, the two-dimensional space can be extended to the three-dimensional space.

The mobile body and mobile body management system of the present disclosure can be suitably used for moving and transporting items such as luggage, parts, and finished products in factories, warehouses, construction sites, physical distribution, hospitals, and the like.

1 ... User, 2a, 2b ... Access point, 10 ... AGV (moving body), 11a, 11b ... Drive wheels (wheels), 11c, 11d, 11e, 11f ... Caster, 12 ... frame, 13 ... transfer table, 14 ... travel control device, 14a ... microcomputer, 14b ... memory, 14c ... storage device, 14d ... communication circuit, 14e ... Positioning device, 16a, 16b ... motor, 15 ... laser range finder, 17a, 17b ... motor drive circuit, 20 ... terminal device (mobile computer such as tablet computer), 50 ... operation management Device, 51 ... CPU, 52 ... Memory, 53 ... Location database (location DB), 54 ... Communication circuit, 55 ... Map database (map DB), 56 ... Image processing circuit , 100 ... mobile management system, 101, 200 ... map creation system, 103 ... fixed sensor, 105 ... map creation device, 107 ... storage device, 109 ... signal processing circuit, 111 ... Interface device, M ... Overall map of moving space

Claims (9)

A mapping system that creates a map that a moving object refers to to estimate its own position.
A fixed sensor that is fixedly installed in the space where the moving body moves, senses a part of the space at a plurality of different times, and outputs sensor data at each time.
It is equipped with a mapping device that receives sensor data at each time and creates a map of at least a part of the space.
The sensor data at each time indicates the position of an object existing in a part of the space at each time.
The map-making device
A storage device that stores the sensor data at each time,
A map creation system including a signal processing circuit that creates local map data that is a map of a part of the space based on the position of a fixed object that is commonly included in all the sensor data at each time. The storage device stores the map data of the space in advance.
The map creation system according to claim 1, wherein the signal processing circuit uses the created local map data to update the map data stored in the storage device. The map creation system according to claim 1 or 2, wherein the signal processing circuit identifiablely indicates the position of a movable object included in a part of the sensor data at each time on a map of a part of the space. The fixed sensor senses a part of the space at time _Tn (n: 1, ..., N; N is an integer of 2 or more).
When the movable object is included in K sensor data (integer of K: 1 or more and less than N) out of N sensor data from time T ₁ to time _TN .
The map creation system according to claim 3, wherein the signal processing circuit identifiablely indicates the position of the movable object on a map of a part of the space when the value of K is equal to or greater than a threshold value. The fixed sensor senses a part of the space at time _Tn (n: 1, ..., N; N is an integer of 2 or more).
When the movable object is included in K sensor data (integer of K: 1 or more and less than N) out of N sensor data from time T ₁ to time _TN .
The mapping system according to claim 3 or 4, wherein the signal processing circuit shows the position of the movable object on a map of a part of the space at a concentration corresponding to a value of K. The fixed sensor senses a part of the space at time _Tn (n: 1, ..., N; N is an integer of 2 or more).
When the movable object is included in K sensor data (integer of K: 1 or more and less than N) out of N sensor data from time T ₁ to time _TN .
Any of claims 3 to 5, wherein the signal processing circuit determines a weight according to a value of K, includes the position of the movable object in a map of a part of the space, and associates the weight with the position of the movable object. The map creation system described in Crab. When the moving body estimates its own position using the map of the space,
The moving body is
With the motor
A drive device that controls the motor to move the moving body,
A memory for storing map data of the space and
A built-in sensor that senses the surrounding space and outputs sensor data,
It has a positioning device that collates the sensor data output by the built-in sensor with the map data of the space stored in the memory, estimates its own position, and outputs reliability data indicating the degree of matching of the collation. Ori,
The mapping system according to any one of claims 2 to 6, wherein the fixed sensor is installed at a position where the degree of matching of the collation is less than a threshold value based on the reliability data. The mapping system according to any one of claims 1 to 7, wherein the fixed sensor is a laser range finder built in a stationary moving body. A mapping device that creates a map that a moving object refers to to estimate its own position.
It is fixedly installed in the space where the moving body moves, senses a part of the space at a plurality of different times, and outputs sensor data indicating the position of an object existing in the part of the space at each time. An interface device that receives the sensor data from a fixed sensor,
A storage device that stores the sensor data at each time,
A map creation device including a signal processing circuit that creates local map data that is a map of a part of the space based on the position of a fixed object that is commonly included in all the sensor data at each time.

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