Self-travelling device

Abstract

To provide a device that regenerates a path by using a newly detected portion during self-travel even upon start of self-travel along a path generated from an unfinished map to improve the efficiency of self-travel.SOLUTION: A patrol travel control part 111 controls a cleaning part 17 to cause a self-travelling device to perform self-travelling along an outer edge while controlling a detection part 16 to cause the self-travelling device to detect the surroundings. A map creation part 112 specifies a shape of an outer edge of a cleaning region and a position and a shape of an obstacle based on data of an already detected portion to create a map. A path generation part 113 generates a path where travelling at the detected portion is performed. A path travelling part 114 causes the self-travelling device to detect the surroundings while travelling along the path. An additional area calculation part 115 calculates an area of an additional portion newly detected. A determination part 116, upon determination that the area of the additional area exceeds a threshold value, causes the path generation part 113 to regenerate a new path for travelling on a detected region including the additional portion where travelling has not yet been performed.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a technique for automatically generating a route along which a self-propelled device travels. [Background technology]

[0002] Various self-propelled devices that travel on their own to perform tasks, such as automatic cleaning robots and security and inspection robots, have been developed. In particular, there has been a growing demand in recent years for technology that allows self-propelled devices to travel thoroughly within a designated area. These self-propelled devices can perform various tasks, such as cleaning, security, and inspection, in a designated area with consistent quality, regardless of the worker's level of proficiency or concentration.

[0003] In order to make the self-propelled device travel thoroughly through a given area, as if it were painting the area, the self-propelled device itself (or its control device) must obtain a route for traveling through the area. Therefore, various technologies for the self-propelled device to generate its own route for traveling on its own are being considered.

[0004] Patent Document 1 discloses a self-propelled robot in which the robot body repeatedly rotates along an imaginary plane formed at a predetermined distance from the inner wall surface of a wall in a house, shifting this imaginary plane inward with each revolution, thereby causing the robot body to propel itself.

[0005] Patent Document 2 discloses a robot cleaner that performs a basic cleaning operation to clean while traveling according to a predetermined traveling rule, then performs an uncleaned area cleaning operation to clean areas that were not cleaned in the basic cleaning operation, and then performs a peripheral cleaning operation to clean around obstacles.

[0006] Patent document 3 discloses an autonomous robot that detects obstacles within a work area, divides the work area into cells, and during work, creates a map by recording the obstacles detected in the work area and the positions of tasks that have been completed on a cell-by-cell basis, recognizes the nearest unworked cell on the map from the current position, and when it detects an obstacle ahead in the direction of travel, performs work while autonomously driving to the recognized unworked cell. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2005-339408 A [Patent Document 2] JP 2005-211366 A [Patent Document 3] JP 2004-326692 A Summary of the Invention [Problem to be solved by the invention]

[0008] However, in many cases, a self-propelled device does not know information about the area before it starts to move, such as the shape of the outer edge of the area to be self-propelled and the positions of obstacles placed within the area. Therefore, there are countless routes for self-propelling the entire area, but some of the routes generated without knowing the information about the area are inefficient, such as driving over the same place multiple times, making unnecessary turns, or dividing a section that can be traveled in a single straight line into multiple sections.

[0009] The self-propelled robot described in Patent Document 1 acquires the positions of walls and obstacles in the center of a room away from the walls based on each travel route within the home that the robot body has traveled on its own, and generates map information for the entire area within the home. However, for example, if the area to be cleaned has many partitions, the self-propelled robot described in Patent Document 1 will need to make multiple revolutions until all the remaining areas in the center are cleaned.

[0010] The robot cleaner described in Patent Document 2 cleans uncleaned areas that were not cleaned in the basic cleaning operation with an uncleaned area cleaning operation, and finally cleans the area around obstacles with a periphery cleaning operation. However, since the robot cleaner described in Patent Document 2 travels by filling in an incomplete map, it is unclear in which direction to search for efficient travel. Therefore, compared to other self-propelled devices, this robot cleaner has a shorter length per route and makes more turns, which can result in poor travel efficiency.

[0011] The autonomous mobile robot described in Patent Document 3 divides the work area into cells and cleans it, so if there are walls or obstacles that are not aligned with the direction in which the cells are arranged, it is easy for the boundaries between the cells to be left uncleaned.

[0012] One of the objects of the present invention is to provide a device that improves the efficiency of self-driving by regenerating a route using newly detected portions during self-driving, even if self-driving is started along a route generated from an incomplete map. [Means for solving the problem]

[0013] The present invention provides, as a first aspect, a self-propelled device that travels around an area along its outer edge while detecting its surroundings, generates a path to travel through the detected parts of the area, and travels along the path while detecting its surroundings and regenerates the path when the area of ​​a newly detected additional part exceeds a threshold.

[0014] According to the self-propelled device of the first aspect, even if self-propelling begins along a route generated from an incomplete map, the efficiency of self-propelling can be improved by regenerating the route using newly detected portions during self-propelling.

[0015] In the self-propelled device of the first aspect, a configuration may be adopted as a second aspect in which the route is regenerated until an area ratio of the already traveled portion to the region reaches a predetermined value.

[0016] According to the self-propelled device of the second aspect, it is possible to self-propel the device until the area ratio of the already detected portion to the area to be self-propelled reaches a predetermined value.

[0017] In the self-propelled device of the first aspect, a configuration in which the threshold value is determined in accordance with a total area of ​​the region may be adopted as a third aspect.

[0018] According to the self-propelled device of the third aspect, the route can be regenerated at a frequency according to the total area of ​​the area to be self-propelled.

[0019] In the self-propelled device of the first aspect, a configuration in which the threshold value is determined according to the number of times the route has been generated may be adopted as a fourth aspect.

[0020] According to the self-propelled device of the fourth aspect, it is possible to regenerate a route with a frequency according to the number of times the route has been generated.

[0021] In the self-propelled device of the first aspect, a configuration may be adopted as a fifth aspect in which, if the route is completed before the area of ​​the additional portion exceeds the threshold, a route for traveling the additional portion is regenerated.

[0022] According to the self-propelled device of the fifth aspect, it is possible to make the self-propelled device travel on an additional portion that is newly detected while traveling on a route and that remains untraveled. [Brief description of the drawings]

[0023] [Figure 1] 1 is a block diagram showing a configuration of a cleaning device 1 according to an embodiment of the present invention. [Diagram 2] 1 is a schematic diagram showing an example of the appearance of a cleaning device 1. FIG. [Diagram 3] FIG. 2 is a diagram showing an example of the configuration of a map DB 121. [Figure 4] FIG. 13 is a diagram showing an example of the configuration of a threshold table 122. [Diagram 5] FIG. 4 is a diagram showing an example of the configuration of a route DB 123. [Figure 6]FIG. 13 is a diagram showing an example of a "spiral" path. [Figure 7] A diagram showing an example of a route taken by "ox plowing". [Figure 8] FIG. 2 is a diagram showing an example of a functional configuration of the cleaning device 1. [Figure 9] 4A and 4B are diagrams for explaining a cleaned area Ra and a detected area Rv, respectively. [Figure 10] 11A and 11B are diagrams for explaining the influence of the maximum detection angle on a detected region Rv. [Figure 11] 4 is a flow chart showing an example of the operation flow of the cleaning device 1. [Figure 12] FIG. 13 is a diagram showing an example of a map created by patrol driving. [Figure 13] FIG. 13 is a diagram showing an example of route regeneration. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] <Embodiment> <Terminology> The following terms used in describing the cleaning device 1 according to the embodiment of the present invention are defined as follows.

[0025] The term "area" refers to a predetermined range of surfaces, such as the ground, floor, or road surface, that are spread out below the device (self-propelled device) of the present invention and that are the subject of processing by the device. An "edge" is an object that surrounds an area. An edge can be, for example, a wall, a curb, a partition, etc. The device of the present invention cannot pass through the edge and cannot go beyond the edge and out of the area. An "obstacle" is an object that exists inside the area and impedes the device's travel. "Running" means moving along an area. Running includes locomotion by reciprocating leg movements, locomotion by rolling movements on wheels, as well as locomotion by flying. "Self-propelled" means that the device of the present invention can move by itself. The "travel width" refers to the width of the portion that the device of the present invention processes as it travels. "Detection" refers to the device of the present invention sensing the surrounding environment and determining the location of the outer edge of the area and each of the obstacles present in the area. The "detection width" refers to the width of the portion where the device of the present invention performs detection as the vehicle travels. A "route" is a path or route along which the device of the present invention travels. This route is generated by the device itself so as to fill the detected portion of the travel width.

[0026] <Cleaning device configuration> Fig. 1 is a block diagram showing the configuration of a cleaning device 1 according to an embodiment of the present invention. The cleaning device 1 shown in Fig. 1 has a processor 11, a memory 12, a communication unit 13, an operation unit 14, a display unit 15, a detection unit 16, and a cleaning unit 17. These are connected to each other via a bus so as to be able to communicate with each other.

[0027] The memory 12 includes a random access memory (RAM), a read only memory (ROM), a solid state drive, a hard disk drive, etc., and stores computer programs (hereinafter simply referred to as programs).

[0028] 1 also stores a map DB 121, a threshold table 122, and a route DB 123. These are used when the processor 11 executes processing.

[0029] The processor 11 controls the cleaning device 1 by reading and executing a program from the memory 12. The processor 11 is, for example, a CPU (Central Processing Unit). The processor 11 may be, for example, a FPGA (Field Programmable Gate Array) or may include an FPGA. The processor may also have an ASIC (Application Specific Integrated Circuit) or other programmable logic device and perform control by using these.

[0030] The communication unit 13 is a communication circuit that connects the cleaning device 1 to other external devices, etc., by wire or wirelessly. The communication unit 13 may communicably connect the cleaning device 1 to various external devices via a communication line such as an intranet or the Internet.

[0031] The operation unit 14 includes operators such as operation buttons, a keyboard, a touch panel, and a mouse for issuing various instructions, and receives operations and sends signals according to the contents of the operations to the processor 11. These operations include, for example, pressing the keyboard, making gestures on the touch panel, and the like.

[0032] The display unit 15 has a display screen such as a liquid crystal display, and displays images under the control of the processor 11. A transparent touch panel of the operation unit 14 may be placed on top of the display screen. The cleaning device 1 does not need to have the operation unit 14 and the display unit 15. The cleaning device 1 may be operated by an external device via the communication unit 13, or may present information to an external device. The cleaning device 1 does not need to have the communication unit 13.

[0033] The detection unit 16 is a group of devices that detects the environment around the cleaning device 1. The detection unit 16 shown in FIG.

[0034] The obstacle sensor 161 is a sensor for detecting an obstacle. The obstacle sensor 161 may be, for example, a sensor using infrared rays, ultrasonic waves, or the like.

[0035] The distance sensor 162 is a sensor that measures the distance to an obstacle. The distance sensor 162 is, for example, a radar or LiDAR (Light Detection and Ranging) that measures the distance to an obstacle by a so-called TOF (Time of Flight) method. The TOF method is a method that measures the distance to an object by using the time it takes for an irradiated radio wave or light to hit an object and be reflected, and for the reflected wave or reflected light to return. Note that the method by which the distance sensor 162 measures the distance is not limited to the TOF method. The distance sensor 162 may measure the distance to an obstacle by, for example, triangulation using the parallax of multiple images captured by a stereo camera or the like.

[0036] The cleaning unit 17 is a group of devices that perform cleaning. The cleaning unit 17 shown in FIG.

[0037] The traveling mechanism 171 is a mechanism that causes the cleaning device 1 to travel under the control of the processor 11. This traveling mechanism 171 is composed of, for example, wheels, a steering wheel that controls the moving direction of the wheels, an axle that rotatably supports the wheels, and a motor that rotates the axle.

[0038] The running mechanism 171 is not limited to having tires, caterpillar tracks, wheels, or the like, and may be, for example, a mechanism that walks by repeatedly touching and lifting off a plurality of legs having one or more joints. Also, the running mechanism 171 does not need to be grounded as long as it is a mechanism that moves the cleaning device 1 along a lower area. For example, the running mechanism 171 may be a mechanism that uses lift generated by driving a propeller or the like to fly the device along a lower area.

[0039] Pad 172 is a cleaning member that polishes and cleans the floor surface directly below cleaning device 1. Pad 172 may have a member such as resin that comes into contact with the floor surface to polish the floor surface, a tank that stores cleaning liquid, a pump that supplies the cleaning liquid from the tank to the floor surface, and the like.

[0040] The squeegee 173 is a member that wipes off dirt that has come loose from the floor surface as a result of cleaning by the pad 172. The squeegee 173 may have a member such as a resin that blocks and collects the cleaning liquid containing dirt that is supplied by the pad 172, and a suction pump or the like that sucks up the collected cleaning liquid.

[0041] Fig. 2 is a schematic diagram showing an example of the appearance of the cleaning device 1. The cleaning device 1 shown in Fig. 2 has a housing 10. An operation unit 14 and a display unit 15 are provided on the top surface of the housing 10. In addition, a detection unit 16 is provided on the front and rear side surfaces of the housing 10. And a cleaning unit 17 is provided on the bottom surface of the housing 10.

[0042] This cleaning device 1 travels in direction D on the ground G of the cleaning area by means of a travel mechanism 171. The obstacle sensor 161 and the distance sensor 162 are attached facing in direction D, i.e., forward. As a result, when the cleaning device 1 moves in direction D, the obstacle sensor 161 and the distance sensor 162 sense an obstacle ahead and measure the distance to the obstacle. Note that the obstacle sensor 161 shown in FIG. 2 is also attached facing backward.

[0043] The processor 11 of the cleaning device 1 performs so-called SLAM (Simultaneous Localization and Mapping) based on, for example, information on the outer edge and the distance to an obstacle measured by the distance sensor 162. As a result, the cleaning device 1 estimates its own position and creates a map of the surroundings. Information on the map created by the processor 11 is stored in the map DB 121 in the memory 12.

[0044] <Map DB configuration> Fig. 3 is a diagram showing an example of the configuration of the map DB 121. This map DB 121 is a database that stores information on maps created for each cleaning area, such as a room to be cleaned. The map DB 121 shown in Fig. 3 has items of map ID and map data. The map ID is identification information that identifies each map showing the shape of the cleaning area.

[0045] The map data is data showing the shape of a cleaning area identified by a corresponding map ID, i.e., a map. The shape of a cleaning area includes the shape of the outer edge of the cleaning area and the shape of obstacles present in the cleaning area. The map data is composed of, for example, a list of multiple points each having an x-coordinate value indicating a position on an x-axis that extends in an east-west direction and corresponds to longitude, and a y-coordinate value indicating a position on a y-axis that extends in a north-south direction and corresponds to latitude. Lines connecting the multiple points listed in the map data show the outer edge of the cleaning area or the outline of obstacles.

[0046] <Threshold table configuration> Fig. 4 is a diagram showing an example of the configuration of threshold table 122. This threshold table 122 is a table that stores threshold values ​​that the cleaning device 1 compares with the area of ​​an added portion. An added portion is a portion that is newly detected while the cleaning device 1 is traveling along a route. Threshold table 122 shown in Fig. 4 has items for the number of times and the threshold value.

[0047] The number of times that the cleaning device 1 has generated a path is described in the number of times field in threshold table 122 shown in Fig. 4. The threshold field in threshold table 122 also stores a threshold value that is compared with the area of ​​the added portion when the cleaning device 1, which has generated a path a corresponding number of times, is traveling by itself along the last generated path.

[0048] That is, the thresholds described in this threshold table 122 are examples of thresholds that are determined according to the number of times a route is generated.

[0049] <Route DB configuration> 5 is a diagram showing an example of the configuration of the route DB 123. The route DB 123 is a database that stores routes for each map. The route DB 123 shown in FIG.

[0050] The map ID list 1231 is a list of map IDs. The map ID list 1231 is made up of the same information as the map IDs stored in the map DB 121.

[0051] The path table 1232 is stored in association with each map ID listed in the map ID list 1231. The path table 1232 is a table that describes, by a plurality of paths, the route along which the cleaning device 1 travels in the cleaning area identified by the corresponding map ID. Here, a "path" is a route that is broken down into a plurality of parts at points along the way. The path table 1232 shown in Fig. 5 has items for path ID, target point, and cleaning necessity.

[0052] The path ID is identification information for identifying each path that constitutes a route. The paths described in the path table 1232 in Fig. 5 are partial routes represented by straight lines from a starting point to an end point. Here, the starting point of the path is the current position of the cleaning device 1, and the end point of the path is the target point. In other words, the target point shown in this path table 1232 is the end point of the path identified by the corresponding path ID.

[0053] The cleaning necessity shown in this path table 1232 is information (flag) indicating whether or not the cleaning device 1 needs to perform cleaning when self-propelling along the path identified by the corresponding path ID.

[0054] After the cleaning area is determined and a map showing the cleaning area is created, the cleaning device 1 generates a path table 1232 in association with the map. In this path table 1232, a route is generated such that the cleaning device 1 fills in the areas that have already been detected with the travel width. This route is made up of multiple continuous paths.

[0055] For example, path IDs "P1", "P2", ... are described in path table 1232 associated with map ID "M01" in Fig. 5. When cleaning the cleaning area of ​​the map indicated by map ID "M01", cleaning device 1 refers to path table 1232, reads out target points in the order of path IDs "P1", "P2", ..., and travels toward each target point for each path. At that time, cleaning device 1 reads out cleaning necessity information associated with each path, and determines whether or not to perform cleaning while traveling along that path.

[0056] 5, the first path identified by the path ID "P1" has "NO" written as the cleaning necessity. This is because the cleaning device 1 moves to the start point of the path (x01, y01) and then starts self-propelling along the path, regardless of where it is located.

[0057] 5 describes straight line paths connecting start points and end points, but paths represented by curved lines may also be described. When paths are represented by curved lines, path table 1232 may store parameters such as curvature, curvature radius, and control points in a Bezier curve in association with each path.

[0058] When the traveling mechanism 171 of the cleaning device 1 is instructed by the processor 11 to move straight along a path, it moves straight toward the target point without changing direction. Then, when the traveling mechanism 171 reaches an obstacle and cannot physically move any further, or when it reaches an area that has already been cleaned, the processor 11 instructs the traveling mechanism 171 to turn and move straight along the next path. The processor 11 generates a path consisting of multiple paths according to a predetermined rule based on information about the shape of the cleaning area that has already been acquired. The algorithm for generating this path includes, for example, "spiral" and "ox plowing."

[0059] 6 is a diagram showing an example of a route using a "spiral." The "spiral" is formed, for example, according to the following multiple rules.

[0060] If there is an edge, obstacle, or cleaned area ahead and there is a direction to the left or right where there is no edge, obstacle, or cleaned area, turn in that direction where there is no edge, obstacle, or cleaned area. If there are no edges or obstacles ahead and there is a cleaned area, and there are edges, obstacles or cleaned areas on either side, continue moving straight. If there is an edge or obstacle ahead and there are cleaned areas on both the left and right, the robot will turn to the side that has the nearest uncleaned area.

[0061] Therefore, when this "spiral" is adopted as an algorithm, the cleaning device 1 moves from the inside to the outside or from the outside to the inside to perform cleaning. When the "spiral" is adopted, the cleaning device 1 generally moves along a trajectory that is close to the sense of a human cleaning, but because dead ends occur more frequently than in the ox plowing method described below, for example, there are cases where the device must traverse a route it has already traversed more than twice, as shown by the dashed line in Fig. 6.

[0062] 7 is a diagram showing an example of a route by "gyutok". "gyutok" is composed of the following multiple rules, for example.

[0063] If moving straight in the initial direction or the opposite direction, continue moving straight until you reach the edge or an obstacle. -If the robot travels straight in the initial direction or the opposite direction and reaches the outer edge or obstacle in front, and there are no outer edges, obstacles, or cleaned areas on either the left or right for a distance at least equivalent to the width of the device, it will turn in the direction where there are no outer edges, obstacles, or cleaned areas, then move a distance equivalent to that width, turn again and travel in the opposite direction to when it traveled straight. If there is an edge or obstacle ahead and there are cleaned areas on both the left and right, the robot will turn to the side that has the nearest uncleaned area.

[0064] Therefore, when this "ox plowing" is adopted as an algorithm, the cleaning device 1 moves back and forth from one end of a room to the other to clean. When "ox plowing" is adopted, the cleaning device 1 moves like an ox plowing a field. The movement route in this case is advantageous when the straight line along the initial direction is long in the cleaning area.

[0065] <Functional configuration of the cleaning device> Fig. 8 is a diagram showing an example of the functional configuration of the cleaning device 1. The processor 11 of the cleaning device 1 reads and executes a program stored in the memory 12, thereby functioning as a patrol driving control unit 111, a map creation unit 112, a route generation unit 113, a route driving unit 114, an additional area calculation unit 115, and a determination unit 116. Note that the communication unit 13, the operation unit 14, and the display unit 15 are not shown in Fig. 8.

[0066] The patrol control unit 111 controls the detection unit 16 to detect the surroundings of the device, and controls the travel mechanism 171 of the cleaning unit 17 to self-propel the device along the outer edge indicated by the detection result by the detection unit 16. This causes the cleaning device 1 to go around the cleaning area. In other words, the cleaning device 1 having the processor 11 functioning as this patrol control unit 111 is an example of a self-propelled device that goes around an area along the outer edge while detecting the surroundings.

[0067] The map creation unit 112 acquires data on the portion of the cleaning area that has already been detected by the detection unit 16 (also called the detected portion) from the patrol control unit 111. Then, based on the acquired data on the detected portion, the map creation unit 112 identifies the shape of the outer edge of the cleaning area and the positions and shapes of obstacles currently found, and creates a map. This map is stored in the map DB 121.

[0068] The path generating unit 113 obtains data indicating the created map and the detected portion from the map creating unit 112. Then, the path generating unit 113 generates a path for traveling through the detected portion according to a predetermined algorithm such as the above-mentioned "spiral" or "ox plowing". That is, the cleaning device 1 having the processor 11 functioning as the path generating unit 113 is an example of a self-propelled device that generates a path for traveling through the detected portion of the area. The generated path is stored in the path DB 123. The memory 12 separately stores the number of times the path has been generated by the path generating unit 113.

[0069] The path traveling unit 114 acquires data indicating the path generated from the path generating unit 113. Then, the path traveling unit 114 controls the traveling mechanism 171 of the cleaning unit 17 to make the device travel along the path indicated by the acquired data. The path traveling unit 114 also controls the detection unit 16 during this traveling to make the device detect the surroundings. That is, the cleaning device 1 having the processor 11 functioning as the path traveling unit 114 is an example of a self-propelled device that travels along a path while detecting the surroundings.

[0070] When the cleaning unit 17 cleans and travels on its own while the detection unit 16 detects the surroundings according to instructions from the path travel unit 114, a cleaned area and a detected area are generated after the cleaning device 1 passes through. FIG. 9 is a diagram for explaining the cleaned area Ra and the detected area Rv. In FIG. 9, the cleaned area Ra is an area that has already been cleaned by the cleaning device 1. Also, in FIG. 9, the detected area Rv is an area that has already been detected by the cleaning device 1.

[0071] 9 is a range that can be detected by the distance sensor 162. This detection range V is represented by, for example, a maximum detection angle θ and a maximum detection distance r. That is, the detection range V is defined within a sector of the cleaning area to be processed by the cleaning device 1, with the position of the distance sensor 162 as the center point, the maximum detection angle θ as the central angle, and the maximum detection distance r as the radius.

[0072] When the traveling mechanism 171 travels on the ground G of the cleaning area in the direction D while the distance sensor 162 detects the detection range V, the area through which the detection range V passes becomes the detected area Rv. In other words, the detected area Rv is an area whose width is the detection width Wv and extends in the direction D.

[0073] Meanwhile, the cleaning device 1 performs cleaning using the pad 172 and squeegee 173 of the cleaning unit 17 while self-propelled. When the traveling mechanism 171 travels in the direction D on the ground G of the cleaning area while the pad 172 and squeegee 173 perform cleaning, a cleaned area Ra of the cleaning area, which is the width through which the pad 172 and squeegee 173 have passed and which extends in the direction D, is cleaned. Therefore, the traveling width Wa shown in FIG. 9 is the width of the cleaned area Ra, which is the larger width of either the pad 172 or the squeegee 173.

[0074] It is desirable that the maximum detection angle of the detection range is greater than two right angles (180 degrees). Figure 10 is a diagram for explaining the effect of the maximum detection angle on the detected region Rv. The detection range U shown in Figure 10(a) is defined as a sector with a maximum detection angle φ and a maximum detection distance s. This maximum detection angle φ is an angle smaller than two right angles.

[0075] In this case, when the cleaning device 1, which has performed detection while moving along direction D, passes an obstacle B such as a pillar, a blind spot Rm occurs on the back side (the side of direction D) of the obstacle B where the distance sensor 162 cannot detect. This is because the maximum detection angle φ is smaller than two right angles, and therefore when the cleaning device 1 passes the obstacle B, as shown in FIG. 10(b), the distance sensor 162 cannot detect the back side of the obstacle B.

[0076] On the other hand, the maximum detection angle θ of the detection range V described above is larger than two right angles. Therefore, as shown in FIG. 10(c), when the cleaning device 1 passes through the obstacle B, the distance sensor 162 can detect the back side of the obstacle B.

[0077] 8 acquires data on an added portion that is newly detected while the cleaning device 1 is traveling along the path in accordance with instructions from the path traveling unit 114. This added portion is a portion that has been added to the detected region Rv since the cleaning device 1 started traveling along the current path. Therefore, the current path along which the cleaning device 1 is traveling does not pass through the added portion.

[0078] The added area calculation unit 115 calculates the area of ​​the added portion indicated by the acquired data. The calculated area data is transmitted to the determination unit .

[0079] The determination unit 116 acquires a threshold value corresponding to the number of times the path has been generated, stored in the memory 12, from the threshold value table 122. Then, the determination unit 116 compares this threshold value with the area of ​​the added portion calculated by the added area calculation unit 115, and determines whether or not the area of ​​the newly detected added portion exceeds the threshold value.

[0080] When the determination unit 116 determines that the area of ​​the newly detected added portion exceeds the threshold, it causes the path generation unit 113 to generate (regenerate) a new path for traveling through an area that has been detected and includes the added portion but has not yet been traveled. That is, the cleaning device 1 having the processor 11 that functions as the determination unit 116 and the path generation unit 113 is an example of a self-propelled device that regenerates a path when the area of ​​the newly detected added portion exceeds the threshold. When the path is regenerated, the processor 11 adds 1 to the number of times the path has been generated to update the memory 12, and stores the new regenerated path in the path DB 123.

[0081] <Display device operation> FIG. 11 is a flow diagram showing an example of the flow of the operation of the cleaning device 1. As shown in FIG. 11, the processor 11 of the cleaning device 1 controls the detection unit 16 and the cleaning unit 17 to perform a "patrol run" that goes around the cleaning area along the outer edge while detecting the surroundings (step S101). Then, when the patrol run is completed, the processor 11 creates a map showing the shape of the cleaning area based on the area that has been detected as a result of this (step S102). According to this map, the outer edges of the cleaning area are all determined, but the inside of the cleaning area may include undetected areas that include obstacles. In other words, this map is a provisional map at the time when the patrol run is completed.

[0082] Fig. 12 is a diagram showing an example of a map created by patrol travel. The cleaning device 1 starts patrol travel along the outer edge of the cleaning area. As the cleaning device 1 patrols, the detection range V described in Fig. 9 travels around the cleaning area, and the area through which the detection range V passes becomes the detected area Rv, as shown in Fig. 12(a).

[0083] Then, when the cleaning device 1 completes a circuit around the cleaning area along the outer edge, the cleaning area is divided into a detected area Rv and an undetected area Ru that is the remaining area that has not yet been detected, as shown in Fig. 12(b). At this time, the processor 11 of the cleaning device 1 creates a map showing the cleaning area based on the detected area Rv, as described above.

[0084] Next, the processor 11 generates a route for the device to travel on the basis of the created map (step S103). The processor 11 cleans while traveling along the generated route (step S104), and detects the surroundings to update the detected area Rv described above (step S105). These steps S104 and S105 are performed in parallel.

[0085] For example, when the parallel processing of the above-mentioned steps S104 and S105 is performed for a certain period of time, the processor 11 judges whether or not the area of ​​the newly detected added portion (also called the added area) exceeds the threshold value shown in the threshold value table 122 (step S106). When it is judged that the added area exceeds the threshold value (step S106; YES), the processor 11 returns the processing to step S103. As a result, the processor 11 discards the currently self-traveling route, and generates (regenerates) a new route for the area of ​​the detected area Rv including the added portion, excluding the cleaned area Ra.

[0086] Fig. 13 is a diagram showing an example of route regeneration. When the detected area Rv shown in Fig. 12(b) is determined by completing the patrol, the processor 11 generates a meandering route so as to fill the detected area Rv with a travel width Wa (see Fig. 9) as shown in Fig. 13(a). Note that the route shown in Fig. 13(a) is generated using the "ox plowing" algorithm described above, but may be generated using other algorithms such as "spiral".

[0087] Then, the processor 11 controls the travel mechanism 171 of the cleaning unit 17 to make the cleaning device 17 move along this path and clean, and also controls the detection unit 16 to make the device detect the surroundings. As a result, a cleaned area Ra is generated in the area where the cleaning device 1 has passed.

[0088] At this time, the path along which the cleaning device 1 travels may deviate from the outer edge, so that an additional portion Rv0 that is newly detected is generated in the undetected region Ru, as shown in FIG. 13(a).

[0089] Then, the processor 11 compares the area of ​​the added portion Rv0 with a threshold value, and when it determines that the area of ​​the added portion Rv0 exceeds the threshold value, it regenerates a route for the robot to travel independently in the range that is included in the new detected area Rv incorporating the added portion Rv0 and is not included in the cleaned area Ra. The regenerated route is generated by combining a plurality of paths that are filled with the travel width Wa described above.

[0090] For example, the range Q shown in FIG. 13(b) is a range that is included in the new detected area Rv incorporating the added part Rv0, but is not included in the cleaned area Ra. The range Q includes the added part Rv0 and the detected area Rv that is adjacent to the added part Rv0 and is not included in the cleaned area Ra. The route before being regenerated in this range Q was divided into left and right as shown in FIG. 13(a). Therefore, when the cleaning device 1 travels on its own along these divided routes, it will travel along each of them at different times. In addition, when the cleaning device 1 travels on its own along this route, it will also make small turns and meander in a narrow range of the range Q that does not include the added part Rv0.

[0091] However, when the processor 11 determines that the area of ​​the added portion Rv0 exceeds the threshold, it regenerates a new path for this range Q as shown in FIG. 13(b). This regenerated path connects the above-mentioned paths that are separated to the left and right into one. Therefore, the cleaning device 1 can clean across the entire width of the cleaning area shown in FIG. 13(b) by moving along this path. This new path has fewer turns and fewer passes than the path before regeneration shown in FIG. 13(a), improving cleaning efficiency.

[0092] 11, when it is determined that the added area does not exceed the threshold value (step S106; NO), the processor 11 determines whether or not traveling along the route is complete (step S107). When it is determined that traveling along the route is not complete (step S107; NO), the processor 11 returns the process to immediately before steps S104 and S105. As a result, the processor 11 continues traveling along the currently traveling route and continues detection.

[0093] On the other hand, when it is determined that traveling along the route is completed (step S107; YES), the processor 11 determines whether or not there is a remaining cleaning area (referred to as a remaining area) (step S108). The remaining area is an additional portion, and is, for example, a cleaning area exceeding a certain area smaller than the above-mentioned threshold. When it is determined that there is this remaining area (step S108; YES), the processor 11 reports on the remaining area (step S109). On the other hand, when it is determined that there is no remaining area (step S108; NO), the processor 11 ends the processing. Note that, when ending the processing, the processor 11 may control the traveling mechanism 171 to travel the device so as to return to the position at the start of self-traveling.

[0094] By executing the above-described process, the cleaning device 1 according to the present invention regenerates a route using the added part when the area of ​​the newly detected added part exceeds a threshold while self-propelled, and self-propels along the newly regenerated route. Therefore, even if the cleaning device 1 starts self-propelling along a route generated from an incomplete map, it can improve cleaning efficiency compared to a self-propelled device that does not regenerate a route using the added part.

[0095] The cleaning device 1 is a computer having a processor 11 and a memory 12. Therefore, the present invention can also be conceived as a cleaning method for causing a computer to execute each of the steps shown in Fig. 11 described above.

[0096] The present invention can also be conceived as a program written to cause a computer to execute each step shown in FIG.

[0097] The configurations, shapes, sizes, and layouts described in the above embodiments are merely schematic to the extent that the present invention can be understood and practiced. Therefore, the present invention is not limited to the described embodiments, and may be modified in various forms without departing from the scope of the technical ideas set forth in the claims.

[0098] <Modification> The above is a description of the embodiment, but the contents of this embodiment may be modified as follows. In addition, the following modifications may be combined.

[0099] <1> In the embodiment described above, the processor 11 performs the determination in step S108 shown in FIG. 10, but this determination does not have to be performed.

[0100] Furthermore, when it is determined in step S108 that there is a remaining area, the processor 11 may regenerate a path for the cleaning device 1 to travel through this remaining area instead of or in addition to step S109 shown in Fig. 10. In this case, the processor 11 may clean the remaining area by traveling by itself along the regenerated path.

[0101] In other words, when it is determined that there is a remaining area as described above, the cleaning device 1 regenerates a route to travel through this remaining area and cleans that route.This is an example of a self-propelled device that regenerates a route to travel through an additional portion if it finishes traveling the route before the area of ​​the additional portion exceeds a threshold value.

[0102] In the above embodiment, the processor 11 ends the process when the travel of the path is completed without the added area exceeding the threshold, but the condition for ending the process is not limited to this. For example, the processor 11 may regenerate the path until the area ratio of the cleaned area Ra to the cleaning area reaches a predetermined value. According to this modification, for example, if the predetermined value is 95%, the cleaning device 1 continues to generate the path, travel along the path, and clean until 95% of the total area of ​​the cleaning area has been cleaned.

[0103] That is, the cleaning device 1 having the processor 11 in this modified example is an example of a self-propelled device that regenerates a route until the area ratio of the already traveled portion to the area reaches a predetermined value. With this configuration, the cleaning device 1 can end cleaning when a predetermined target cleaning completion rate (coverage rate) is reached for the entire area of ​​the cleaning area.

[0104] <2> In the above-described embodiment, the threshold table 122 defines a threshold corresponding to each number of times a route is generated, but a threshold that is not dependent on the number of times a route is generated may be defined.

[0105] Furthermore, the thresholds are stored in advance in threshold table 122, but processor 11 may generate them according to the situation such as the detection result of detection unit 16, and write them into threshold table 122 each time. For example, when processor 11 performs patrol driving and creates a map, it may calculate the area surrounded by the outer edge determined by this map (i.e., the total area of ​​the cleaning area), and determine the threshold according to this total area. In this case, it is sufficient that the formula, rules, etc. for deriving the threshold from the total area are determined in advance.

[0106] That is, the cleaning device 1 having the processor 11 in this modified example is an example of a self-propelled device in which the threshold is determined according to the total area of ​​the area. With this configuration, the cleaning device 1 can set the threshold so that the frequency of path regeneration is reduced when the area of ​​the cleaning area is relatively large, and the frequency of path regeneration is increased when the area is relatively small. That is, the processor 11 of the cleaning device 1 in this modified example can determine the above-mentioned threshold so that the time required to regenerate the path is appropriately balanced with the time required for self-propelling the path.

[0107] <3> In the above-described embodiment, the process performed by the cleaning device 1 is to clean the portion that it has self-propelled along the path by using the pad 172 and squeegee 173 of the cleaning unit 17. However, the self-propelled device according to the present invention is not limited to a device that performs cleaning. The self-propelled device according to the present invention may be a device that self-propels through an area for the purpose of processing other than cleaning, such as inspecting for dirt, malfunctions, cracks, etc., finding radiation leaks, hazardous materials, etc. [Explanation of symbols]

[0108] 1...cleaning device, 10...housing, 11...processor, 111...patrol driving control unit, 112...map creation unit, 113...route generation unit, 114...route driving unit, 115...additional area calculation unit, 116...judgment unit, 12...memory, 121...map DB, 122...threshold table, 123...route DB, 1231...map ID list, 1232...path table, 13...communication unit, 14...operation unit, 15...display unit, 16...detection unit, 161...obstacle sensor, 162...distance sensor, 17...cleaning unit, 171...driving mechanism, 172...pad, 173...squeegee.

Claims

1. A self-propelled device that travels around an area along the outer edge while detecting the surroundings, generates a route that travels through the detected parts of the area, and regenerates the route when the area of ​​a newly detected additional part exceeds a threshold value while traveling along the route while detecting the surroundings.

2. The route is regenerated until the area ratio of the already traveled portion to the region becomes a predetermined value.

2. The self-propelled device of claim 1.

3. The threshold is determined according to the total area of ​​the region.

2. The self-propelled device of claim 1.

4. The threshold is determined according to the number of times the route is generated.

2. The self-propelled device of claim 1.

5. If the route is completed before the area of ​​the added portion exceeds the threshold, a route that travels the added portion is regenerated.

2. The self-propelled device of claim 1.

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