JP7649955B2 - Map generation method, program, map generation system, and mobile robot equipped with the same - Google Patents

Description

The present disclosure relates to a map generation method, a program, a map generation system, and a mobile robot equipped with the same. More specifically, the present disclosure relates to a map generation method, a program, a map generation system, and a mobile robot equipped with the same, which generate an overall map of a moving area in which a mobile robot moves.

Patent Document 1 discloses a system in which a robot explores the interior of a room, which is an unknown environment, and creates a map of the room. During exploration, the robot autonomously navigates the environment and executes a process to detect objects (e.g., walls) present in the environment. When the robot detects an object in the environment, it saves the detected object as map data.

Special Publication No. 2020-533720

When controlling the movement of a robot using a map created by the above system, the position of the robot is specified, for example, by the coordinates of a two-dimensional Cartesian coordinate system represented by two orthogonal axes (e.g., the X-axis and the Y-axis) set on the map. Here, if the X-axis or the Y-axis on the map is not parallel to the wall of the room, in order to move the robot along the wall, it is necessary to set the movement route of the robot so that the robot moves in a direction that intersects diagonally with the X-axis and the Y-axis, respectively. This poses the problem that it becomes difficult to design the movement route for the robot (mobile robot).

The objective of the present disclosure is to provide a map generation method, program, and map generation system that can generate a map that makes it easy to design a route for a mobile robot to travel, and a mobile robot equipped with the same.

A map generation method according to one aspect of the present disclosure is a map generation method for generating an overall map of a moving area in which a mobile robot moves. The map generation method includes a partial map generation process, a map synthesis process, a selection process, and a correction process. In the partial map generation process, a plurality of partial maps corresponding to a plurality of partial areas in the moving area are generated. In the map synthesis process, the plurality of partial maps are synthesized to generate the overall map. In the selection process, a representative map having a direction element for identifying a direction is selected from the plurality of partial maps. In the correction process, the orientation of the overall map generated in the map synthesis process is corrected based on the direction element present in the representative map.

A program according to one aspect of the present disclosure is a program for causing a computer system to execute the map generation method.

A map generation system according to one aspect of the present disclosure generates an overall map of a moving area in which a mobile robot moves. The map generation system includes a partial map generation unit, a map synthesis unit, a selection unit, and a correction unit. The partial map generation unit generates a plurality of partial maps each corresponding to a plurality of partial areas in the moving area. The map synthesis unit synthesizes the plurality of partial maps to generate the overall map. The selection unit selects, from the plurality of partial maps, a representative map having a direction element for identifying a direction. The correction unit corrects the orientation of the overall map generated by the map synthesis unit based on the direction element present in the representative map.

A mobile robot according to one embodiment of the present disclosure includes a mobile body, a movement control unit that controls the movement of the mobile body, a range sensor that detects objects present around the mobile body, and the map generation system.

According to the present disclosure, it is possible to generate a map that makes it easy to design a route for a mobile robot to travel.

FIG. 1 is a schematic system configuration diagram of a robot system including a map generation system according to an embodiment of the present disclosure. FIG. 2 is a schematic plan view of a moving area for which the map generating system generates a map. FIG. 3 is a diagram showing a partial map of the first straight section generated by the map generation system. FIG. 4 is a diagram showing a partial map of the first turning section generated by the map generating system. FIG. 5 is a diagram showing a partial map of the second straight section generated by the map generation system. FIG. 6 is a diagram showing a partial map of the third straight section generated by the map generating system. FIG. 7 is a diagram showing a partial map of the fourth straight section generated by the map generating system. FIG. 8 is a diagram showing a partial map of the fifth straight section generated by the map generating system. FIG. 9 is a diagram showing a partial map of the sixth straight section generated by the map generating system. FIG. 10 is a diagram showing a partial map of the seventh straight section generated by the map generating system. FIG. 11 is a diagram showing a composite map obtained by the map generating system of the above by combining a plurality of partial maps. FIG. 12 is a diagram showing a composite map obtained by the map generating system of the above-mentioned embodiment by combining a plurality of partial maps and erasing the frame lines of the plurality of partial maps. FIG. 13 is a diagram showing a partial map of the first straight section generated by the map generation system. FIG. 14 is a diagram for explaining a detection method in which the map generating system detects a linear movement area from a representative drawing. FIG. 15 is a diagram for explaining a detection method in which the map generation system detects a linear movement area from a representative drawing. FIG. 16 is a diagram for explaining a detection method in which the map generating system detects a linear movement area from a representative drawing. FIG. 17 is a diagram for explaining a detection method in which the map generation system detects a linear movement area from a representative drawing. FIG. 18 is a diagram for explaining a detection method in which the map generating system detects a linear movement area from a representative drawing. FIG. 19 is a diagram for explaining a detection method in which the map generating system detects a linear movement area from a representative drawing. FIG. 20 is a flowchart illustrating the operation of the map generating system.

(Embodiment)
(1) Overview A map generation method according to this embodiment, a program therefor, a map generation system that executes the map generation method, and a mobile robot equipped with the same will be described with reference to Figures 1 to 20. Each figure described in the following embodiment is a schematic diagram, and the ratio of sizes and thicknesses of each component in each figure does not necessarily reflect the actual dimensional ratio.

Figure 1 is a schematic system configuration diagram of a robot system 1 including a mobile robot 3 equipped with a map generation system 7. The robot system 1 is a system for controlling the mobile robot 3 that moves within a predetermined movement area A1 (see Figure 2). As shown in Figure 1, the robot system 1 includes the mobile robot 3 and a control system 2 that controls the mobile robot 3.

The map generation system 7 generates an overall map MP1 (see FIG. 12) of the movement area A1 in which the mobile robot 3 moves. The map generation system 7 includes a partial map generation unit 71, a map synthesis unit 72, a selection unit 73, and a correction unit 74.

The partial map generation unit 71 generates a number of partial maps MP21 to MP28 (see Figures 3 to 10) that respectively correspond to a number of partial areas within the movement area A1.

The map synthesis unit 72 synthesizes multiple partial maps MP21 to MP28 to generate the overall map MP1 (see Figure 12).

The selection unit 73 selects a representative map from the multiple partial maps MP21 to MP28 that contains a directional element for identifying a direction.

The correction unit 74 corrects the orientation of the overall map MP1 generated by the map synthesis unit 72 based on the directional elements present in the representative map.

The "mobile robot" in this disclosure includes an automated guided vehicle (AGV) and a drone. The "mobile robot" in this disclosure is, for example, a wheeled, crawler, or legged (including walking) robot. After acquiring data of the overall map MP1 generated by the map generation system 7 from the map generation system 7, the mobile robot 3 moves autonomously along a movement path based on, for example, a control instruction received from the control system 2. In other words, the control system 2 indirectly controls the movement of the mobile robot 3 by outputting a control instruction to the mobile robot 3. Note that the mobile robot 3 may have a function of not only moving within a predetermined movement area A1, but also performing various tasks such as, for example, transport, picking, welding, mounting, display, customer service, security, assembly, and inspection. In the following embodiment, an example will be described in which the mobile robot 3 is an AGV that transports an object by moving within a movement area A1 in a facility such as a shopping mall. Before the map generation system 7 generates the overall map MP1 of the moving area A1, the mobile robot 3 does not have data on the overall map MP1. Therefore, a controller for inputting control instructions is connected to the mobile robot 3, and the user operates the controller to manually input one or more control instructions (e.g., a control instruction for multiple straight movements or multiple turning movements) that instruct a series of operations, thereby inputting one or more control instructions to the mobile robot 3. The mobile robot 3 performs a series of operations (a series of straight movements or a series of turning operations) in the moving area A1 based on the one or more control instructions input from the controller, and the partial map generation unit 71 generates a partial map of a partial area including the area in which the mobile robot 3 performed the series of operations. The communication between the controller and the mobile robot 3 may be wired communication or wireless communication.

The "mobile area" in this disclosure is a space in which one or more mobile robots 3 are deployed, and the mobile robots 3 move within this mobile area A1 upon receiving control instructions from the control system 2. Examples of the mobile area A1 include stores (e.g., shopping malls, etc.), warehouses, factories, construction sites, logistics centers, offices, parks, homes, schools, hospitals, stations, airports, and parking lots. Furthermore, when the mobile robot 3 is deployed inside a vehicle, such as inside a ship, train, or airplane, the inside of the vehicle becomes the mobile area A1. In the following embodiment, an example is described in which the mobile area A1 is a store such as a shopping mall.

The overall map MP1 is a map that represents the entire moving area A1. When the mobile robot 3 moves inside a facility, the moving area A1 may be the entire inside of the facility, or may be only the area inside the facility where the mobile robot 3 moves. The multiple partial maps MP21 to MP28 are maps that respectively correspond to multiple partial areas in the moving area A1. The multiple partial areas represented by the multiple partial maps MP21 to MP28 may partially overlap, or may not overlap at all. The map synthesis unit 72 generates the overall map MP1 by synthesizing multiple partial maps. For example, the map synthesis unit 72 generates the overall map MP1 by synthesizing the multiple partial maps MP21 to MP28 by superimposing the multiple partial maps MP21 to MP28 on a map area that represents the entire moving area A1. The size of the overall map MP1 is preferably set to match the size of the map that is created by synthesizing the multiple partial maps MP21 to MP28.

A "directional element" is an element that can identify the direction of the representative map among the elements displayed on the representative map. The directional element is preferably an element that has a straight line portion with a certain length so that the direction of the representative map can be identified. The directional element may include, for example, a straight line element that represents a wall or cabinet with a certain length that exists in the movement area A1. In other words, the directional element may include, for example, a straight line element that exists in the representative map and has a length equal to or greater than a first threshold. The first threshold is preferably, for example, a length several times the total length of the mobile robot 3, and the length of the first threshold can be changed appropriately depending on the size of the mobile robot 3, the width of the movement area A1, etc. In addition, the directional element may include, for example, a linear movement area that represents a linear passage that exists in the movement area A1. In other words, the directional element may include a linear movement area that is an area in which the mobile robot 3 can move linearly and has a length equal to or greater than a second threshold. The width of the linear movement area may be equal to or greater than the width of the mobile robot 3, and when the mobile robot 3 transports an object, it may be equal to or greater than the maximum width of the mobile robot 3 and the object. In addition, the second threshold is preferably a length that is, for example, several times the total length of the mobile robot 3, and the length of the second threshold can be changed as appropriate depending on the size of the mobile robot 3, the width of the movement area A1, etc.

The correction unit 74 corrects the orientation of the overall map MP1 based on the directional elements present in the representative map, and can correct the orientation of the overall map MP1 so that, for example, one of the two orthogonal axes set in the overall map MP1 is parallel to the orientation of the directional elements. As a result, when moving the mobile robot 3 along the directional elements, it is sufficient to move the mobile robot 3 along the orthogonal axis set in the overall map MP1. Therefore, the map generation system 7 of this embodiment can generate an overall map MP1 that makes it easy to design the travel route along which the mobile robot 3 will travel.

As described above, the mobile robot 3 of this embodiment is equipped with a map generation system 7. The mobile robot 3 is also equipped with a moving body 30 (see FIG. 2), a movement control unit 37, and a range sensor 33.

The movement control unit 37 controls the movement of the moving body 30.

The range sensor 33 detects objects present around the moving body 30 (e.g., the walls of a room that is the moving area A1).

The mobile robot 3 is equipped with a map generation system 7, which allows the mobile robot 3 to generate an overall map MP1 that makes it easy to design the route along which the mobile robot 3 will travel.

(2) Details Below, a map generation system 7 that executes a map generation method according to this embodiment, a mobile robot 3 equipped with the map generation system, and a robot system 1 including the mobile robot 3 will be described with reference to FIGS. 1 to 20.

As described above, the robot system 1 includes the mobile robot 3 and the control system 2 that controls the movement of the mobile robot 3. The robot system 1 also includes a creation support system 4 in which application software is installed for setting a route along which the mobile robot 3 can move in the movement area A1. The robot system 1 also includes operation terminals 5 and 6 in which application software is installed for monitoring the operating state of the mobile robot 3 and inputting movement instructions for the mobile robot 3 to the control system 2. The operation terminal 5 is, for example, a notebook personal computer, and the operation terminal 6 is, for example, a tablet computer. One or more wireless access points AP1 that relay communication between the mobile robot 3 and the control system 2 are installed in the movement area A1.

(2.1) Mobile Robot As described above, the mobile robot 3 includes the mobile body 30, the movement control unit 37, the range measurement sensor 33, and the map generation system 7. The mobile robot 3 also includes a second control unit 36 having the functions of the movement control unit 37 and the map generation system 7, a second communication unit 31, a second storage unit 32, a position estimation unit 34, and a traveling system 35.

The mobile robot 3 is, for example, a robot that runs on wheels on the floor of a facility that will be the mobile area A1. The running system 35 controls the rotation direction and speed of multiple drive wheels to allow the robot to run in a desired direction at a desired speed on the floor of the facility that will be the mobile area A1.

The second communication unit 31 performs wireless communication with the control system 2. Specifically, the second communication unit 31 communicates with the control system 2 and the like via the wireless access point AP1 and the network NT1. As the communication method between the second communication unit 31 and the wireless access point AP1, an appropriate communication method such as wireless communication or wired communication is adopted.

The second storage unit 32 has at least one of the following memories: a RAM (Random Access Memory) and a ROM (Read Only Memory). The second storage unit 32 stores at least map information including a plurality of partial maps created by the map generation system 7 and an overall map MP1 of the entire movement area A1. The second storage unit 32 also stores identification information and the like assigned to the mobile robot 3.

The range sensor 33 detects objects present within a measurement range centered on the range sensor 33. The range sensor 33 includes, for example, a sensor such as LiDAR (Light Detection and Ranging). LiDAR irradiates light (laser light) to the surroundings and measures the distance to and direction of an object based on the light reflected by objects present around the mobile robot 3. Note that the range sensor 33 is not limited to LiDAR, and may include sensors such as radar (Radio Detection and Ranging), sonar sensors, and image sensors (cameras). Radar is a sensor that uses electromagnetic waves (radio waves) such as microwaves to measure the distance to and direction of an object based on the waves reflected by objects present around the mobile robot 3.

When the overall map MP1 has been generated by the map generation system 7, the position estimation unit 34 estimates the position (current position) of the mobile robot 3 in the movement area A1 based on the overall map MP1 stored in the second storage unit 32. The position estimation unit 34 estimates the position coordinates of the current position in the movement area A1 based on, for example, detection information of surrounding objects (e.g., walls, shelves, equipment, etc. present in the movement area A1) by the range measurement sensor 33 and the overall map MP1. Note that when the overall map MP1 has not been generated and the partial map generation unit 71 is generating a partial map, the position estimation unit 34 estimates the position (current position) of the mobile robot 3 based on the partial map that is in the process of being generated.

The position estimation unit 34 may estimate the position coordinates of the current position of the mobile robot 3 in the mobile area A1 using a local positioning system (LPS) that uses a radio wave beacon. The position estimation unit 34 may estimate the current position based on the radio wave intensity when a beacon signal transmitted from each of a plurality of transmitters installed above the mobile area A1 (such as the ceiling of the facility) is received by a receiver installed in the mobile robot 3 and the installation position of each transmitter. The position estimation unit 34 may also estimate the position coordinates of the current position of the mobile robot 3 using a global navigation satellite system (GNSS) such as the Global Positioning System (GPS).

The second control unit 36 controls the overall operation of the mobile robot 3. The second control unit 36 is mainly composed of, for example, a computer system having one or more processors and memory. The functions of the second control unit 36, for example the functions of the movement control unit 37 and the map generation system 7, are realized by the processor of the computer system executing a program recorded in the memory of the computer system. The program may be recorded in the memory, or may be provided via a telecommunications line such as the Internet, or may be recorded on a non-temporary recording medium such as a memory card and provided.

The second control unit 36 causes the position estimation unit 34 to perform an operation of estimating the current position every time a predetermined update period (e.g., 0.1 seconds) elapses, and updates the estimation result of the current position of the mobile robot 3. Then, the second control unit 36 causes the second communication unit 31 to transmit the estimation result of the current position together with the identification information of the mobile robot 3 to the mobile robot 3.

When the movement control unit 37 has acquired data of the overall map MP1 generated by the map generation system 7 from the map generation system 7, the movement control unit 37 moves the mobile robot 3 based on, for example, a control instruction received by the second communication unit 31 from the control system 2. The control instruction from the control system 2 includes information about a movement route for moving the mobile robot 3 from a first point to a second point, and includes, for example, the coordinates of a node corresponding to the first point and a node corresponding to the second point. The control instruction may also include the coordinates of a node corresponding to one or more third points through which the mobile robot 3 passes on its way from the first point to the second point.

When the movement control unit 37 receives a control instruction from the control system 2, it controls the traveling system 35 based on the position (current position) estimated by the position estimation unit 34, the map information of the movement area A1, and the control instruction, and moves the mobile robot 3 along the movement path.

As described above, the map generation system 7 includes a partial map generation unit 71, a map synthesis unit 72, a selection unit 73, and a correction unit 74. The map generation system 7 further includes a noise removal unit 75.

The map generation system 7 is a system for generating an overall map MP1 that represents the entire moving area A1. When generating the overall map MP1, the mobile robot 3 patrols the moving area A1, and the map generation system 7 generates the overall map MP1 of the moving area A1 based on information about objects detected by the range sensor 33 during the patrol.

Here, the patrol route that the mobile robot 3 patrols within the moving area A1 to generate the overall map MP1 is divided into a plurality of sections in which the mobile robot 3 performs a series of operations. The series of operations includes a series of straight movements in which the mobile robot 3 moves straight in one direction, and a series of turning movements in which the mobile robot 3 turns in one direction. Therefore, the plurality of sections includes one or more straight sections in which a series of straight movements is performed, and one or more turning sections in which a series of turning movements is performed. Here, the "series of straight movements" is not limited to the movement of the mobile robot 3 moving forward straight, but may include the movement of the mobile robot 3 moving straight and the movement of turning at a predetermined allowable angle or less. In other words, the series of straight movements may include a movement in which the mobile robot 3 moves forward while moving laterally within a predetermined allowable range in a direction perpendicular to the direction in which the mobile robot 3 moves straight. In addition, the "series of turning movements" includes a movement of turning on the spot (pivot turning) without including a straight movement. A "series of turning movements" includes a single turning movement or multiple turning movements performed consecutively, the total turning angle of which exceeds the allowable angle.

Figure 2 shows an example of a patrol route that the mobile robot 3 patrols to create an overall map, using multiple arrows. The patrol route shown in Figure 2 includes, for example, seven straight sections (first to seventh straight sections M1 to M7) and, for example, six turning sections (first to sixth turning sections R1 to R6).

The partial map generating unit 71 generates a plurality of partial maps MP21 to MP28 (see Figures 3 to 10) corresponding to the plurality of partial areas within the movement area A1. While the mobile robot 3 moves through the partial area to be created among the plurality of partial areas, the partial map generating unit 71 generates a partial map corresponding to the partial area to be created by measuring the positions of objects present within the measurement range of the range sensor 33 provided on the mobile robot 3.

In this embodiment, each time the mobile robot 3 performs a series of straight movements or a series of turning movements while patrolling the patrol route, a partial map is created based on the position of the target object measured by the range sensor 33. More specifically, the mobile robot 3 executes a series of movements (a series of straight movements or a series of turning movements) based on a control instruction manually input by, for example, a user using a controller. When the mobile robot 3 finishes a series of movements based on a control instruction, the user manually inputs the next control instruction to the mobile robot 3, causing the mobile robot 3 to execute the series of movements based on the control instruction. In this way, the user inputs multiple control instructions to the mobile robot 3 in sequence, causing the mobile robot 3 to execute multiple movements based on the multiple control instructions in sequence and move along the patrol route.

Here, the partial map generating unit 71 generates a partial map of the partial area moved while the mobile robot 3 performs a series of operations based on the control instruction (for example, a series of straight movements or a series of turning movements). In other words, at the timing when the control instruction input to the mobile robot 3 or the control instruction executed by the mobile robot 3 is switched, the partial map generating unit 71 generates a partial map of the partial area moved while the mobile robot 3 performs a series of operations based on the control instruction. Therefore, when the mobile robot 3 moves (straight or turning) along a patrol route as shown in FIG. 2, the partial map generating unit 71 generates a partial map each time the mobile robot 3 moves through the first to seventh straight sections M1 to M7 and the first to sixth turning sections R1 to R6. Here, the size of the partial map is the size of the area that can be measured while the mobile robot 3 moves (straight or turning). Therefore, the size of each of the multiple partial maps created while the mobile robot 3 moves through the multiple sections (the first to seventh straight sections M1 to M7, and the first to sixth turning sections R1 to R6) is a size that corresponds to the amount of movement (movement distance or movement angle) in each section. Furthermore, the area represented by the partial map created by the mobile robot 3 moving through each of the multiple sections becomes a partial area. Note that, although the two partial areas corresponding to two adjacent sections among the multiple sections partially overlap, they may be separate areas.

The map synthesis unit 72 synthesizes a plurality of partial maps to generate the overall map MP1. Specifically, the map synthesis unit 72 generates the overall map MP1 by superimposing a plurality of partial maps (e.g., partial maps MP21 to MP28) generated by the mobile robot 3 traveling through a plurality of sections included in the patrol route onto a map area representing the entire movement area A1. In FIG. 11, for the sake of convenience, the frames of the plurality of partial maps MP21 to MP28 are each shown with a dashed line, but the overall map MP1 generated by the map synthesis unit 72 is a map without the frames of the plurality of partial maps MP21 to MP28 as shown in FIG. 12. Note that, although arrows representing two orthogonal axes (X-axis and Y-axis) set in the overall map MP1 are shown in FIG. 11 and FIG. 12, the arrows representing the X-axis and Y-axis are shown merely for the sake of convenience and do not actually exist.

The selection unit 73 selects a representative map that contains directional elements (e.g., straight line elements, straight line movement areas, etc.) for specifying a direction from among the multiple partial maps MP21 to MP28 generated by the partial map generation unit 71. For example, the direction of a map showing the interior of a room can be specified by the direction of the walls of the room, cabinets present in the room, or passages through which the mobile robot 3 can move straight within the room. Therefore, it is preferable for the selection unit 73 to select as the representative map from among the multiple partial maps MP21 to MP28 a partial map that contains directional elements that include at least one of straight line elements such as walls or cabinets, and straight line movement areas that represent passages through which the mobile robot 3 can move straight, etc.

The inventors have estimated that a partial map of a straight section where the mobile robot 3 moves in a straight line is more likely to have a straight line element or a directional element such as a straight line movement area than a partial map of a straight section where the mobile robot moves in a straight line is shorter. Therefore, in the partial map generation process for generating the partial map, the selection unit 73 selects the partial map of the partial area where the mobile robot moves in a straight line the longest for map generation as the representative map. If a directional element cannot be detected in the representative map selected by the selection unit 73, the selection unit 73 may select a partial map generated while the mobile robot 3 moves in the straight section where the straight line movement distance is the next longest as the representative map. The correction unit 74 detects the directional element from the representative map selected by the selection unit 73 and corrects the direction of the entire map MP1, and the process for detecting the directional element can be reduced compared to the case where the process for detecting the directional element is performed for all of the multiple partial maps MP21 to MP28.

The selection unit 73 may also select two or more partial maps generated while the mobile robot 3 moves through two or more straight sections in which the linear movement distance is equal to or greater than the third threshold, and the correction unit 74 may detect directional elements from the two or more partial maps to perform correction processing. In other words, the selection unit 73 may select, in the partial map generation process, two or more partial maps in which the linear movement distance of the mobile robot 3 for map generation is equal to or greater than the third threshold, in order as representative maps. Then, the correction unit 74 may correct the orientation of the entire map MP1 generated by the map synthesis unit 72 based on the directional elements present in the two or more partial maps selected as representative maps. Here, the third threshold may be set as a distance of a predetermined length (absolute value), or may be set as a relative value (e.g., a value of 90%) with respect to the linear movement distance in the section in which the linear movement distance is the longest. The selection unit 73 selects one partial map as the representative map from the two or more partial maps in a predetermined order. The order in which the representative maps are selected is, for example, in order of the linear movement distance. When the correction unit 74 detects a directional element from the partial map selected as the representative map, the selection unit 73 ends the process of switching the representative map, and the correction unit 74 corrects the orientation of the entire map MP1 based on the directional element. In this way, by detecting a directional element from two or more partial maps whose travel distance is equal to or greater than the third threshold, the process of detecting the directional element can be reduced compared to the case where the process of detecting the directional element is performed from all of the multiple partial maps.

The correction unit 74 corrects the orientation of the overall map MP1 generated by the map synthesis unit 72 based on the direction elements present in the representative map selected by the selection unit 73. In the overall map MP1, a two-dimensional orthogonal coordinate system made up of two orthogonal axes (X-axis and Y-axis) is set in order to identify the position of the mobile robot 3. The overall map MP1 is, for example, a horizontally long rectangular map, with the longer side of the overall map MP1 being the X-axis direction and the shorter side of the overall map MP1 being the Y-axis direction. The correction unit 74 corrects the orientation of the overall map MP1 so that the direction elements are parallel to the X-axis direction or the Y-axis direction. In other words, the correction unit 74 corrects the orientation of all elements displayed on the overall map MP1 so that the direction elements are parallel to the X-axis direction or the Y-axis direction of the overall map MP1.

The correction unit 74 may correct the orientation of the multiple partial maps MP21 to MP28 before they are combined, based on the directional elements present in the representative map. In other words, the correction unit 74 may generate an overall map MP1 with corrected orientation by having the map combination unit 72 combine the multiple partial maps MP21 to MP28 after their orientations have been corrected. Here, if a directional element can be detected in each of the multiple partial maps MP21 to MP28, the correction unit 74 may correct the orientation of each of the multiple partial maps MP21 to MP28, based on the directional element detected in each of the multiple partial maps MP21 to MP28. Then, the map combination unit 72 may generate an overall map MP1 by combining the multiple partial maps MP21 to MP28 after their orientations have been corrected by the correction unit 74.

The noise removal unit 75 executes a noise removal process for removing objects located on the movement route along which the mobile robot 3 moved for map generation in the partial map generation process in at least one of the multiple partial maps MP21 to MP28 and the overall map MP1. When generating the partial maps MP21 to MP28, if a person or object is present on the movement route (the above-mentioned patrol route) of the mobile robot 3 before or after the mobile robot 3 passes, a partial map may be generated in which an object is present on the movement route. If an object is present on the movement route, this movement route cannot be used as a route along which the mobile robot 3 moves. However, since the movement route is the route along which the mobile robot 3 moved in order to generate the partial maps MP21 to MP28, it is considered to be a route along which the mobile robot 3 can pass without any problems. Therefore, the noise removal unit 75 removes objects located on the movement route on the multiple partial maps MP21 to MP28, and can generate partial maps MP21 to MP28 in which no objects that would be an obstacle to the movement of the mobile robot 3 are present on the movement route. The noise removal unit 75 may remove objects located on the movement route from the overall map MP1 after it has been synthesized by the map synthesis unit 72, and can generate an overall map MP1 in which no objects that would be an obstacle to the movement of the mobile robot 3 are present on the movement route.

(2.2) Creation Support System The creation support system 4 is realized, for example, by a computer system. The creation support system 4 acquires data of the overall map MP1 created by the mobile robot 3, for example, via the control system 2. The creation support system 4 supports the task of creating map information that sets on the overall map MP1 a route along which the mobile robot 3 can move within the movement area A1. The map information created by the creation support system 4 is held by the control system 2 and the mobile robot 3. The control system 2 controls the movement of the mobile robot 3 based on this map information. The creation support system 4 may be located inside or outside the facility.

The creation support system 4 includes a third communication unit 41, a third memory unit 42, a UI unit 43, and a route creation unit 44.

The third communication unit 41 communicates with the control system 2 and the like via the network NT1. As the communication method between the third communication unit 41 and the control system 2, an appropriate communication method such as wireless communication or wired communication is adopted.

The third memory unit 42 has at least one of RAM and ROM. The third memory unit 42 stores the overall map MP1 created by the mobile robot 3 and the map information created by the path creation unit 44.

The UI unit 43 has an input unit (e.g., a keyboard, a mouse, a pointing device, a touch panel, etc.) that accepts user operations, and a display device that displays a screen for creating map information, etc. The UI unit 43 outputs information that the user inputs using the input unit to the route creation unit 44.

The route creation unit 44 creates map information based on the overall map MP1 created by the mobile robot 3 and information on routes that the mobile robot 3 can travel, which is input from the UI unit 43. Using the UI unit 43, the user sets multiple nodes on the overall map MP1 that the mobile robot 3 can travel on, and one or more links between any two nodes that indicate sections along which the mobile robot 3 can travel. Here, the route along which the mobile robot 3 can travel is composed of multiple nodes and one or more links connecting any two nodes. When the setting information for the nodes and links is input from the UI unit 43, the route creation unit 44 creates map information by adding setting information on routes along which the mobile robot 3 can travel to the overall map MP1.

When the route creation unit 44 finishes creating the map information, it stores the created map information data in the third storage unit 42 and transmits it from the third communication unit 41 to the control system 2. The control system 2 stores the map information data received from the creation support system 4 in the first storage unit 22.

(2.3) Control System The control system 2 is realized by, for example, a computer system. The control system 2 outputs control instructions including at least one of an instruction to move the mobile robot 3 and an instruction to transport an object by the mobile robot 3. The control system 2 may be located inside a facility included in the movement area A1 or outside the facility.

The control system 2 includes a first communication unit 21, a first memory unit 22, a route search unit 23, and a first control unit 24.

The first communication unit 21 communicates with the mobile robot 3 via the network NT1 and the wireless access point AP1. The first communication unit 21 also communicates with the creation support system 4 and the operation terminals 5 and 6 via the network NT1. The first communication unit 21 may also communicate with the operation terminals 5 and 6 via the network NT1 and the wireless access point AP1. An appropriate communication method such as wireless communication or wired communication is adopted as the communication method between the first communication unit 21 and the wireless access point AP1, the creation support system 4, and the operation terminals 5 and 6.

The first storage unit 22 has at least one of a RAM and a ROM. The first storage unit 22 stores first map information related to a map of the movement area A1, route information indicating the movement route of the mobile robot 3 searched by the route search unit 23, and the like.

The route search unit 23 searches for a travel route along which the mobile robot 3 will move, based on the first map information, current position information regarding the current position of the mobile robot 3 received from the mobile robot 3, and transport instruction information received from the operation terminal 5 or 6. Based on the first map information and the transport instruction information, the route search unit 23 searches for a travel route along which, for example, the mobile robot 3 will move from its current position to the location of an object, and then transport the object to the destination location.

When a first node serving as a starting point and a second node serving as a destination point are specified from among the multiple nodes set in the first map information, the route search unit 23 searches for a travel route from the first node to the second node. Here, the route search unit 23 may search for a route that shortens the travel distance or travel time of the mobile robot 3 between the first node and the second node as the travel route.

When a first node serving as a starting point, a third node serving as a relay point, and a second node serving as a destination point are specified from among the multiple nodes set in the first map information, the route search unit 23 searches for a travel route from the first node through the third node to arrive at the second node. Here, the route search unit 23 may search as a travel route a route that shortens the travel distance or travel time of the mobile robot 3 between the first node and the third node, and shortens the travel distance or travel time of the mobile robot 3 between the third node and the second node.

The first control unit 24 causes the path search unit 23 to search for a movement path for the mobile robot 3 based on the current position information received from the mobile robot 3, the transport instruction received from the operation terminal 5 or 6, and the first map information. The first control unit 24 creates a control instruction to move the mobile robot 3 along the movement path based on the path information searched by the path search unit 23, and causes the first communication unit 21 to transmit the control instruction to the mobile robot 3.

(2.4) Operation Terminal The operation terminals 5 and 6 are realized by, for example, a computer system. The operation terminals 5 and 6 are used to input, for example, a transport instruction for instructing the transport of an object to the control system 2.

The operation terminal 5 or 6 includes a UI unit that accepts user operations and a fourth communication unit that communicates with the control system 2 via the network NT1 or the like. The fourth communication unit may also communicate with the control system 2 via the wireless access point AP1 and the network NT1 or the like.

When a user inputs a transport instruction to transport an object in the movement area A1 to a desired destination using, for example, the UI section of the operation terminal 5, the operation terminal 5 transmits transport instruction information based on the transport instruction input by the user to the control system 2 via the network NT1 or the like. The transport instruction information includes, for example, at least information on the object to be transported, information on the location of the object, and information on the location of the destination of the object.

(3) Description of Operation The operation of the map generation system 7 of this embodiment will be described with reference to Figures 2 to 20. Note that the flowchart shown in Figure 20 is merely an example of the map generation method according to this embodiment, and the order of the processes may be changed as appropriate, and processes may be added or omitted as appropriate.

When the map generation system 7 generates an overall map MP1 of the moving area A1, the mobile robot 3 moves along a patrol course (path indicated by arrows in FIG. 2) that patrols the moving area A1 based on control instructions from the control system 2, for example, and the partial map generation unit 71 generates the partial map. Here, the patrol course shown in FIG. 2 includes multiple sections that respectively correspond to the multiple partial areas. The multiple sections include multiple straight sections M1-M7 along which the mobile robot 3 moves straight, and multiple turning sections R1-R6 along which the mobile robot 3 moves in a turning motion.

To move the mobile robot 3 along a patrol course, the user operates the controller with the mobile robot 3 at the starting point of each section and inputs control instructions to move the robot through each section.

When the mobile robot 3 moves through a certain section based on control instructions input from the controller (step S1), the partial map generator 71 generates a partial map representing a partial area including the section based on the measurement results measured by the range sensor 33 during the movement (step S2).

Here, we will explain the multiple partial maps that are generated by the mobile robot 3 moving along the patrol course shown in Figure 2 with reference to Figures 3 to 10.

First, the mobile robot 3 moves 10 m in a straight line in an arbitrary direction from point P1, which is the starting point of the patrol course, to point P2. The section from point P1 to point P2 is called the first straight section M1. The partial map generation unit 71 generates a partial map MP21 (see FIG. 3) of a partial area corresponding to the first straight section M1. When the generation of the entire map MP1 is started, the coordinate system of the partial map MP21 is not determined. Therefore, the partial map generation unit 71 creates the partial map MP21 by provisionally determining the coordinates of point P1, which is the starting point, as (0,0), the direction in which the mobile robot 3 advances in the first straight section M1 as the X-axis direction, and the direction perpendicular to the X-axis direction as the Y-axis direction. In addition, in the first straight section M1, the direction in which the mobile robot 3 advances is provisionally determined as the negative X-axis direction, and the rightward direction as viewed from the mobile robot 3 is provisionally determined as the positive Y-axis direction. In the first straight section M1, the mobile robot 3 moves forward 10 m, so the coordinates of point P2 are (-10, 0).

The mobile robot 3 turns 90 degrees clockwise around point P2. The section in which it turns around point P2 is called the first turning section R1. The partial map generator 71 generates a partial map MP22 (see FIG. 4) of the partial area corresponding to the first turning section R1.

The mobile robot 3 moves 1 m in a straight line from point P2 in the positive direction of the Y axis to point P3 (-10, 1). The section from point P2 to point P3 is called the second straight line section M2. The partial map generation unit 71 generates a partial map MP23 (see FIG. 5) of the partial area corresponding to the second straight line section M2.

The mobile robot 3 turns 90 degrees counterclockwise around point P3. The section in which it turns and moves around point P3 is called the second turning section R2. The partial map generator 71 generates a partial map of a partial area corresponding to the second turning section R2 around point P3. Note that partial maps generated in turning sections after the second turning section R2 are not shown.

The mobile robot 3 moves 3 m in a straight line in the negative direction of the X-axis from point P3 to point P4 (-13, 1). The section from point P3 to point P4 is called the third straight line section M3. The partial map generation unit 71 generates a partial map MP24 (see FIG. 6) of the partial area corresponding to the third straight line section M3.

The mobile robot 3 turns 90 degrees clockwise around point P4. The section in which it turns and moves around point P4 is called the third turning section R3. The partial map generator 71 generates a partial map of a partial area corresponding to the third turning section R3 around point P4.

The mobile robot 3 moves 7 m in a straight line from point P4 in the positive direction of the Y axis to point P5 (-13, 8). The section from point P4 to point P5 is called the fourth straight line section M4. The partial map generator 71 generates a partial map MP25 (see FIG. 7) of a partial area corresponding to the fourth straight line section M4. Note that because there is an obstacle in the fourth straight line section M4, the mobile robot 3 cannot move straight from point P4 to point P5, and moves straight from point P4 to point P5 by performing a series of straight line movements that include straight line movements and turning movements at a predetermined allowable angle or less.

The mobile robot 3 turns approximately 45 degrees clockwise around point P5. The section in which it turns around point P5 is called the fourth turning section R4. The partial map generator 71 generates a partial map of a partial area corresponding to the fourth turning section R4 around point P5.

The mobile robot 3 moves 5 m in a straight line from point P5 in the positive direction of the X-axis to point P6 (-8, 8). The section from point P5 to point P6 is called the fifth straight line section M5. The partial map generation unit 71 generates a partial map MP26 (see FIG. 8) of the partial area corresponding to the fifth straight line section M5.

The mobile robot 3 turns approximately 90 degrees clockwise around point P6. The section in which it turns and moves around point P6 is called the fifth turning section R5. The partial map generator 71 generates a partial map of a partial area corresponding to the fifth turning section R5 around point P6.

The mobile robot 3 moves 8 m in a straight line from point P6 in the negative Y-axis direction to point P7 (0, 8). The section from point P6 to point P7 is called the sixth straight line section M6. The partial map generating unit 71 generates a partial map MP27 (see FIG. 9) of the partial area corresponding to the sixth straight line section M6.

The mobile robot 3 turns approximately 90 degrees counterclockwise around point P7. The section in which the robot turns around point P7 is called the sixth turning section R6. The partial map generator 71 generates a partial map of a partial area corresponding to the sixth turning section R6 around point P7.

The mobile robot 3 moves 8 m in a straight line from point P7 in the positive direction of the X-axis to point P8 (0,0). Point P8 is the same point as the starting point P1. The section from point P7 to point P8 (point P1) is called the seventh straight line section M7. The partial map generation unit 71 generates a partial map MP28 (see FIG. 10) of the partial area corresponding to the seventh straight line section M7.

When the mobile robot 3 finishes moving along the patrol route, the generation of partial maps is completed for all of the sections (i.e., the multiple partial areas) included in the patrol route. When the partial map generation unit 71 completes the generation of all partial maps, or when the mobile robot 3 has completed traveling through all partial areas (step S3: Yes), the selection unit 73 selects a representative map from the multiple partial maps (step S4). For example, the selection unit 73 selects, from among the multiple partial maps, a partial map corresponding to a partial area in which the mobile robot 3 moves in a straight line the longest as the representative map. Table 1 below shows the relationship between the partial maps MP21, MP23 to MP28 generated in the first to seventh straight sections M1 to M7, respectively, and the straight line movement distance in the first to seventh straight sections M1 to M7. In the example of Table 1, the selection unit 73 selects the partial map MP21 in which the mobile robot 3 moves in a straight line the longest as the representative map.

When the representative map is selected, the correction unit 74 performs a process of detecting directional elements (straight line elements or linear movement areas) from the representative map. First, the correction unit 74 determines whether or not straight line elements are present in the partial map MP21 selected as the representative map (step S5). The correction unit 74 performs a process of detecting straight line elements extending in one direction from the representative map, and determines whether or not the length of the detected straight line elements is equal to or greater than a first threshold. If a straight line element whose length is equal to or greater than the first threshold is present in the representative map (step S5: Yes), the correction unit 74 detects the straight line element whose length is equal to or greater than the first threshold as a straight line element, and estimates the angle at which the straight line element intersects with the X-axis (step S6).

On the other hand, if the representative map does not contain a straight line element whose length is equal to or greater than the first threshold (step S5: No), the correction unit 74 determines whether or not a straight-line movement area exists in the partial map MP21 selected as the representative map (step S7).

Figure 14 shows an example of a partial map MP30 in which a linear movement area DE2 exists, and the process of detecting the linear movement area DE2 will be explained using this partial map MP30 as an example.

As shown in FIG. 15, the correction unit 74 draws multiple line segments L1 and L2 in the blank areas of the partial map M30 so that they are arranged at equal intervals parallel to the X-axis direction. Here, the solid line segment L1 is a line segment whose length is equal to or greater than the second threshold, and the dotted line segment L2 is a line segment whose length is less than the second threshold. In the example of FIG. 15, there is one line segment L1 whose length is equal to or greater than the second threshold.

The correction unit 74 draws the multiple line segments L1 and L2 in the blank area of the partial map M30 by increasing the intersection angle θ1 between the multiple line segments L1 and L2 and the X-axis direction (the line segment L4 parallel to the X-axis direction) by a predetermined angle (for example, 1 degree). Figure 16 shows an example of drawing the multiple line segments L1 and L2 when the intersection angle θ1 is 1 degree, Figure 17 shows an example of drawing the multiple line segments L1 and L2 when the intersection angle θ1 is 3 degrees, and Figure 18 shows an example of drawing the multiple line segments L1 and L2 when the intersection angle θ1 is 5 degrees. Here, the correction unit 74 detects the area in which the multiple line segments L1 are arranged as the linear movement area DE2 when the number of line segments L1 whose length is equal to or greater than the second threshold is maximum. In other words, the correction unit 74 detects the area where the number of line segments L1 is maximum when multiple line segments L1 whose length is equal to or greater than the second threshold are arranged in parallel at equal intervals as the linear movement area DE2. In the example shown in FIG. 16 to FIG. 18, when multiple line segments L1 and L2 are drawn so that the crossing angle θ1 is 3 degrees, the number of line segments L1 is the maximum of seven. Therefore, when the crossing angle θ1 is 3 degrees, the correction unit 74 detects the area where multiple line segments L1 are arranged in parallel at equal intervals (step S7: Yes) as the linear movement area DE2. In addition, the correction unit 74 estimates the crossing angle θ1 when the number of line segments L1 is maximum as the angle at which the linear movement area DE2 intersects with the X-axis (step S8).

On the other hand, if the representative map does not include a linear movement area (step S7: No), the selection unit 73 selects a new representative map from one or more partial maps that have not been selected as the representative map (step S9). The correction unit 74 then returns to step S5 and performs processing to detect directional elements (straight line elements or linear movement areas) from the new representative map.

When the correction unit 74 detects directional elements from the representative map and estimates the angles of the directional elements (steps S6 and S8), the map synthesis unit 72 synthesizes multiple partial images to generate an overall map MP1 (see Figures 11 and 12) (step S10).

Then, the correction unit 74 corrects the orientation of the entire map MP1 based on the orientation of the direction element detected from the representative map (step S11). FIG. 3 is an example of a partial map MP21 detected as a representative map. In the example of FIG. 3, the orientation of the straight line element DE1 present in the partial map MP21 is parallel to the X-axis direction, so the correction unit 74 does not correct the orientation of the entire map MP1. On the other hand, as shown in FIG. 13, when the intersection angle between the straight line element DE1 present in the partial map MP21 and the line segment L3 parallel to the X-axis is θ2, the correction unit 74 corrects the orientation of the entire map MP1 by rotating the entire map MP1 by an angle (-θ2). In the entire map MP1 whose orientation has been corrected, the walls of the room represented by the straight line element DE1 become parallel to the X-axis direction.

Also, as shown in Figure 17, when the intersection angle between the linear movement area present in the partial map MP30 and a line segment L4 parallel to the X-axis is θ1, the correction unit 74 corrects the orientation of the entire map MP1 by rotating the entire map MP1 by an angle (-θ1). Figure 19 shows the state in which the partial map MP30 has been rotated by an angle (-θ1), and in the partial map MP30 whose orientation has been corrected, the extension direction of the linear movement area becomes parallel to the X-axis direction.

In this way, the correction unit 74 corrects the orientation of the overall map MP1 based on the orientation of the directional element (straight line element or linear movement area), thereby generating an overall map MP1 in which the orientation of the directional element is parallel to either the X-axis direction or the Y-axis direction. In other words, in the overall map MP1, a wall or cabinet represented by a straight line element that is a directional element, or a linear passage represented by a linear movement area, is arranged parallel to either the X-axis direction or the Y-axis direction.

For example, if the overall map MP1 is generated so that the wall represented by the directional element is parallel to the X-axis direction, then the control system 2 only needs to give the mobile robot 3 a control instruction to move it from coordinates (X1, Y1) to coordinates (X2, Y1) if the mobile robot 3 is to move parallel to the wall. Also, the control system 2 only needs to give the mobile robot 3 a control instruction to move it from coordinates (X1, Y1) to coordinates (X1, Y2) if the mobile robot 3 is to move in a direction perpendicular to the wall. Therefore, since it is only necessary to give the mobile robot 3 a control instruction to change either the X or Y coordinate, it becomes easy to specify the destination coordinates, and a map can be generated that makes it easy to design the route the mobile robot 3 will travel.

When the correction process of step S11 is completed, the noise removal unit 75 performs a noise removal process (step S12) to remove objects located on the movement route (the above-mentioned patrol route) along which the mobile robot 3 moved in order to generate the map in the partial map generation process (step S2) in the overall map MP1. Although a person or object that is temporarily on the movement route before or after the mobile robot 3 passes may be displayed on the partial map, the movement route is a route that the mobile robot 3 has traveled on. Therefore, by the noise removal unit 75 removing objects located on the movement route (the above-mentioned patrol route) in the overall map MP1, the control system 2 can use the movement route as a path along which the mobile robot 3 can move. The noise removal unit 75 may perform a noise removal process to remove objects located on the movement route in multiple partial maps, or may generate the overall map MP1 by combining the partial maps after noise removal.

In the flowchart of FIG. 20, the map generation system 7 detects straight line elements from the representative map, and detects linear movement areas if the straight line elements cannot be detected, but the order of detection may be reversed. That is, the map generation system 7 may detect straight line movement areas from the representative map, and detect straight line elements if the straight line movement areas cannot be detected. Furthermore, the map generation system 7 may perform both a process of detecting straight line elements from the representative map and a process of detecting straight line movement areas from the representative map, and correct the orientation of the overall map MP1 based on the straight line elements or the straight line movement areas. In addition, when both straight line elements and straight line movement areas are detected from the representative map, it is easier to identify the direction of the straight line elements than the straight line movement areas, so it is preferable that the correction unit 74 corrects the orientation of the overall map MP1 based on the straight line elements.

(4) Modifications The above embodiment is merely one of various embodiments of the present disclosure. The above embodiment can be modified in various ways depending on the design and the like as long as the object of the present disclosure can be achieved. In addition, the same function as the map generation system 7 may be embodied in a map generation method, a computer program, or a non-transitory recording medium on which a program is recorded. A map generation method according to one aspect is a method for generating an entire map MP1 of a moving area A1 in which a mobile robot 3 moves. The map generation method includes a map generation step, a map synthesis step, a selection step, and a correction step. In the partial map generation step, a plurality of partial maps corresponding to a plurality of partial areas in the moving area A1 are generated. In the map synthesis step, the plurality of partial maps are synthesized to generate the entire map MP1. In the selection step, a representative map having a direction element for specifying a direction is selected from the plurality of partial maps. In the correction step, the orientation of the entire map MP1 generated in the map synthesis step is corrected based on the direction element present in the representative map. A (computer) program according to one aspect is a program for causing a computer system to execute the above map generation method.

Below, we will list some variations of the above embodiment. The variations described below can be applied in appropriate combinations.

The executing entity of the map generation system 7 or the map generation method in the present disclosure includes a computer system. The computer system is mainly composed of a processor and a memory as hardware. The processor executes a program recorded in the memory of the computer system, thereby realizing the function of the executing entity of the map generation system 7 or the map generation method in the present disclosure. The program may be pre-recorded in the memory of the computer system, may be provided through an electric communication line, or may be provided by being recorded in a non-transitory recording medium such as a memory card, an optical disk, or a hard disk drive that can be read by the computer system. The processor of the computer system is composed of one or more electronic circuits including a semiconductor integrated circuit (IC) or a large scale integrated circuit (LSI). The integrated circuits such as IC or LSI referred to here are called different names depending on the degree of integration, and include integrated circuits called system LSI, VLSI (Very Large Scale Integration), or ULSI (Ultra Large Scale Integration). Furthermore, a field-programmable gate array (FPGA) that is programmed after the manufacture of the LSI, or a logic device that allows reconfiguration of the connection relationship within the LSI or reconfiguration of the circuit partition within the LSI, can also be used as a processor. The electronic circuits may be integrated into one chip, or may be distributed among multiple chips. The chips may be integrated into one device, or may be distributed among multiple devices. The computer system referred to here includes a microcontroller having one or more processors and one or more memories. Therefore, the microcontroller is also composed of one or more electronic circuits including a semiconductor integrated circuit or a large-scale integrated circuit.

In addition, it is not essential for the map generation system 7 that multiple functions are concentrated in one housing, and the components of the map generation system 7 may be distributed across multiple housings. Furthermore, at least some of the functions of the map generation system 7 may be realized by the cloud (cloud computing) or the like.

In addition, in the above robot system 1, the control system 2, the creation support system 4, and the operation terminals 5 and 6 are realized by separate computer systems, but the control system 2 may have the functions of the operation terminals 5 and 6, or the creation support system 4 may have the functions of the operation terminals 5 and 6. Also, the operation terminals 5 and 6, the control system 2, and the creation support system 4 may be realized by one computer system. That is, in the above robot system 1, the control system 2, the creation support system 4, and the operation terminals 5 and 6 are distributed among multiple devices, but at least some of the functions of the control system 2, the creation support system 4, and the operation terminals 5 and 6 may be integrated into one housing.

In the above embodiment, the map generation system 7 is provided in the mobile robot 3, but it is not essential that the map generation system 7 is provided in the mobile robot 3, and the map generation system 7 may be provided outside the mobile robot 3.

In the robot system 1 described in the above embodiment, the number of mobile robots 3 is one, but the robot system 1 may include multiple mobile robots 3. Even if the robot system 1 includes multiple mobile robots 3, it is sufficient that one of the multiple mobile robots 3 is equipped with the map generation system 7, and the map generation system 7 equipped in one mobile robot 3 generates the entire map of the moving area A1. In addition, the multiple partial maps used to generate the entire map may be generated by one mobile robot 3, or may be generated by multiple mobile robots 3 in a shared manner. Then, the map synthesis unit 72 equipped in one of the mobile robots 3 may generate the entire map by synthesizing the multiple partial maps generated by the multiple mobile robots 3. In addition, a server capable of communicating with the multiple mobile robots 3 may include the map synthesis unit 72, and the map synthesis unit 72 equipped in the server may generate the entire map by synthesizing the multiple partial maps generated by the multiple mobile robots 3.

In addition, the mobile robot 3 is not limited to an AGV, but may be an automated truck or material handling equipment such as a forklift.

In addition, when the mobile robot 3 is a transport robot that transports an object, the object transported by the mobile robot 3 is an article, or a pallet or cart on which the article is placed. When the mobile robot 3 is used in a factory, the object transported by the mobile robot 3 may include parts or materials to be supplied to a manufacturing device, a finished product or semi-finished product manufactured by the manufacturing device, or a parts supplying device that supplies parts to the manufacturing device.

(summary)
As described above, the map generation method of the first aspect is a map generation method for generating an overall map (MP1) of a moving area (A1) in which a mobile robot (3) moves. The map generation method includes a partial map generation step, a map synthesis step, a selection step, and a correction step. In the partial map generation step, a plurality of partial maps (MP21 to MP28) corresponding to a plurality of partial areas in the moving area (A1) are generated. In the map synthesis step, the plurality of partial maps (MP21 to MP28) are synthesized to generate an overall map (MP1). In the selection step, a representative map having direction elements (DE1, DE2) for specifying a direction is selected from the plurality of partial maps (MP21 to MP28). In the correction step, the orientation of the overall map (MP1) generated in the map synthesis step is corrected based on the direction elements (DE1, DE2) present in the representative map.

According to this aspect, in the correction process, the orientation of the overall map (MP1) is corrected based on the directional elements (DE1, DE2) present in the representative map, and the orientation of the overall map (MP1) can be corrected so that, for example, one of the two orthogonal axes set in the overall map (MP1) is parallel to the orientation of the directional elements (DE1, DE2). As a result, when moving the mobile robot (3) along the directional elements present in the overall map (MP1), it is sufficient to move the mobile robot (3) along the orthogonal axis set in the overall map (MP1). Therefore, according to the map generation method of the first aspect, it is possible to generate an overall map (MP1) that makes it easy to design a movement route for the mobile robot (3) to move.

In the map generation method of the second aspect, in the first aspect, the directional elements include straight line elements (DE1) that exist in the representative map and whose length is equal to or greater than a first threshold value.

According to this aspect, the orientation of the overall map (MP1) can be corrected based on the straight line element (DE1) present in the representative map.

In the map generation method of the third aspect, in the first or second aspect, the directional element includes a linear movement area (DE2) that exists in the representative map. The direction of the linear movement area (DE2) is an area in which the mobile robot (3) can move linearly, and the length is equal to or greater than the second threshold.

According to this aspect, the orientation of the overall map (MP1) can be corrected based on the orientation of the linear movement area (DE2) present in the representative map.

In the fourth aspect of the map generation method, in the third aspect, the correction step detects, from the representative map, an area in which the number of line segments (LN1) is maximum when multiple line segments (LN1) whose length is equal to or greater than a second threshold are arranged in parallel at equal intervals, as the linear movement area (DE2).

According to this aspect, the orientation of the overall map (MP1) can be corrected based on the orientation of the linear movement area (DE2) present in the representative map.

In the map generation method of the fifth aspect, in any of the first to fourth aspects, in the partial map generation step, while the mobile robot (3) moves through a partial area to be generated among a plurality of partial areas, the range sensor (33) equipped on the mobile robot (3) measures the positions of objects present within the measurement range, thereby generating partial maps (MP21 to MP28) corresponding to the partial area to be generated.

According to this embodiment, partial maps (MP21 to MP28) can be generated based on the measurement results obtained by the range sensor (33) while the mobile robot (3) moves through the partial area.

The sixth aspect of the map generation method is any one of the first to fifth aspects, in which, in the partial map generation step, each time the mobile robot (3) performs a series of actions based on the control instructions, a partial map (MP21 to MP28) of the partial area traveled during the series of actions is generated.

According to this embodiment, partial maps (MP21 to MP28) can be generated when a series of operations based on a control instruction is completed, in other words, when the control instruction is switched.

The map generation method of the seventh aspect is the fifth or sixth aspect and includes a noise removal step. In the noise removal step, objects located on the route traveled by the mobile robot (3) for map generation in the partial map generation step are removed from at least one of the plurality of partial maps (MP21 to MP28) and the overall map (MP1).

According to this aspect, it is possible to generate an overall map (MP1) in which no objects exist on the travel route.

In the map generation method of the eighth aspect, in any of the fifth to seventh aspects, in the selection step, the partial map (MP21 to MP28) of the partial area in which the mobile robot (3) has traveled the longest linear distance for map generation in the partial map generation step is selected as the representative map.

According to this aspect, partial maps (MP21 to MP28) in which straight line elements or straight line movement areas are likely to exist can be selected as representative maps.

In the map generation method of the ninth aspect, in any of the fifth to seventh aspects, in the selection step, two or more partial maps (MP21 to MP28) in which the distance traveled in a straight line by the mobile robot (3) for map generation is equal to or greater than a third threshold value in the partial map generation step are selected in order as representative maps. In the correction step, the orientation of the overall map (MP1) generated in the map synthesis step is corrected based on the directional elements (DE1, DE2) present in the two or more partial maps (MP21 to MP28) selected as the representative maps.

According to this aspect, directional elements are detected from two or more partial maps (MP21 to MP28) in which the travel distance is equal to or greater than the third threshold, so the amount of processing required to detect directional elements can be reduced compared to when directional elements are detected from all of the multiple partial maps (MP21 to MP28).

The program of the tenth aspect is a program for causing a computer system to execute the map generation method of any one of the first to ninth aspects.

According to this aspect, it is possible to generate an overall map (MP1) that makes it easy to design the route along which the mobile robot (3) will move.

The map generation system of the eleventh aspect generates an overall map (MP1) of a moving area (A1) in which a mobile robot (3) moves. The map generation system includes a partial map generation unit (71), a map synthesis unit (72), a selection unit (73), and a correction unit (74). The partial map generation unit (71) generates a plurality of partial maps (MP21 to MP28) corresponding to a plurality of partial areas in the moving area (A1). The map synthesis unit (72) synthesizes the plurality of partial maps (MP21 to MP28) to generate an overall map (MP1). The selection unit (73) selects a representative map having direction elements (DE1, DE2) for specifying a direction from the plurality of partial maps (MP21 to MP28). The correction unit (74) corrects the orientation of the overall map (MP1) generated by the map synthesis unit (72) based on the direction elements (DE1, DE2) present in the representative map.

According to this aspect, the correction unit (74) corrects the orientation of the overall map (MP1) based on the directional elements (DE1, DE2) present in the representative map, and can correct the orientation of the overall map (MP1) so that, for example, at least one of the two orthogonal axes set in the overall map (MP1) is parallel to the orientation of the directional elements (DE1, DE2). As a result, when moving the mobile robot (3) along the directional elements present in the overall map (MP1), it is sufficient to move the mobile robot (3) along the orthogonal axes set in the overall map (MP1). Therefore, according to the map generation system (7) of the eleventh aspect, it is possible to generate an overall map (MP1) that makes it easy to design a movement route for the mobile robot (3) to move.

The mobile robot (3) of the 12th aspect includes a mobile body (30), a movement control unit (37) that controls the movement of the mobile body (30), a range sensor (33) that detects objects present around the mobile body (30), and the map generation system (7) of the 11th aspect.

According to this aspect, it is possible to generate an overall map (MP1) that makes it easy to design the route along which the mobile robot (3) will move.

Not limited to the above aspects, various configurations (including modified examples) of the map generation system (7) according to the above embodiment can be embodied as a map generation method, a (computer) program, or a non-transitory recording medium on which a program is recorded, etc.

The configurations according to the second to ninth aspects are not essential to the map generation method and may be omitted as appropriate.

3 Mobile robot 7 Map generation system 30 Mobile body 33 Range sensor 37 Movement control unit 71 Partial map generation unit 72 Map synthesis unit 73 Selection unit 74 Correction unit A1 Movement area DE1 Straight line element (directional element)
DE2 Linear movement area (directional element)
LN1 Line segment MP1 Overall map MP21-MP28 Partial maps

Claims (12)

A map generation method for generating an overall map of a moving area in which a mobile robot moves, comprising the steps of:
a partial map generating step of generating a plurality of partial maps respectively corresponding to a plurality of partial areas within the moving area;
a map synthesis step of synthesizing the plurality of partial maps to generate the overall map;
a selection step of selecting a representative map having a direction element for specifying a direction from the plurality of partial maps;
and a correction step of correcting the orientation of the entire map generated in the map synthesis step based on the directional element present in the representative map.
Map generation method. The directional elements include straight line elements that exist in the representative map and have a length equal to or greater than a first threshold value.
The map generating method of claim 1 . the direction element includes a linear movement area present in the representative map;
The linear movement area is an area in which the mobile robot can move linearly, and the length of the area is equal to or greater than a second threshold value.
A map generating method according to claim 1 or 2. In the correction step, a region in which a number of line segments, each having a length equal to or greater than the second threshold, is maximum when the line segments are arranged in parallel at equal intervals from the representative map is detected as the linear movement region.
The map generating method according to claim 3. In the partial map generating step, a range sensor provided in the mobile robot measures positions of objects present within a measurement range while the mobile robot moves through a partial region to be generated among the plurality of partial regions, thereby generating a partial map corresponding to the partial region to be generated.
A map generating method according to any one of claims 1 to 4. In the partial map generating step, each time the mobile robot performs a series of operations based on one or a plurality of control instructions, a partial map of a partial area through which the mobile robot has moved while performing the series of operations is generated.
A map generating method according to any one of claims 1 to 5. a noise removing step of removing, from at least one of the plurality of partial maps and the overall map, objects located on a route along which the mobile robot has moved for map generation in the partial map generating step,
A map generating method according to claim 5 or 6. In the selection step,
In the partial map generating step, a partial map of a partial area in which a linear movement distance traveled by the mobile robot is the longest for map generation is selected as the representative map.
A map generating method according to any one of claims 5 to 7. In the selection step, two or more partial maps in which a linear movement distance traveled by the mobile robot for map generation is equal to or greater than a third threshold are selected in order as the representative map in the partial map generation step,
In the correction step, a direction of the entire map generated in the map synthesis step is corrected based on the direction elements present in the two or more partial maps selected as the representative map.
A map generating method according to any one of claims 5 to 7. In the computer system,
A program for executing the map generating method according to any one of claims 1 to 9. A map generation system for generating an overall map of a moving area in which a mobile robot moves, comprising:
a partial map generating unit that generates a plurality of partial maps corresponding to a plurality of partial areas within the moving area;
a map synthesis unit that synthesizes the plurality of partial maps to generate the overall map;
a selection unit that selects a representative map having a direction element for specifying a direction from the plurality of partial maps;
A correction unit that corrects the orientation of the entire map generated by the map synthesis unit based on the directional element present in the representative map.
Map generation system. A moving body,
A movement control unit that controls the movement of the moving body;
A range sensor that detects an object existing around the moving object;
The map generating system according to claim 11,
Mobile robot.

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