Mobile Robot System

Abstract

To provide a mobile robot system which determines a target stop position so as to enable implementation of predetermined work in short time even when positional deviation has arisen between a set stop position candidate and an actual stop position.SOLUTION: A mobile robot system comprises: a data management section containing environment data related to a structure of a work object, robot data related to a movable range of a manipulation part and a moving range of a mobile mechanism, teaching data related to predetermined work, and stop precision data that is stop precision of the mobile mechanism; and a mobile control section which includes a stop position candidate retrieval part for retrieving a work enabled area and retrieving a stop position candidate by using the environment data, the robot data and the teaching data, and further, includes a target stop position determination part for determining a target stop position capable of implementing the teaching data from the stop position candidate, by using the stop position candidate and the stop precision data.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a mobile robot system that moves by a moving mechanism and performs a predetermined task by a manipulation unit. [Background technology]

[0002] 2. Description of the Related Art In response to the trend toward labor-saving and automation of work at various work sites, mobile robot systems that travel to the same work site as people, arrive at a target stopping position, and then perform a specified task are being developed and researched.

[0003] Background art in this technical field includes, for example, JP 2017-016359 A (Patent Document 1) and JP 2006-159399 A (Patent Document 2).

[0004] Patent document 1 describes an autonomous mobile robot system that has a memory unit that stores spatial information indicating the position in a movement space for each subspace that makes up the movement space, attribute information indicating whether each subspace will impede function, and a target object position indicating the position of the target object, a position estimation means that estimates the autonomous mobile robot's current position and attitude, a path search means that sets a movement target position and calculates a movement path from the autonomous position to the movement target position, and a movement control means that controls the autonomous mobile robot to move along the movement path, where the path search means determines a position at which the function can be exerted for the target object from the positional relationship between the position of the subspace that will impede function, which is determined from the spatial information and attribute information, and the target object position, and sets the movement target position to this position (see abstract of Patent document 1).

[0005] Patent document 2 describes a working mobile robot system that has an object position and orientation acquisition unit, a movement unit, a manipulation unit, a control unit, a detection unit that acquires external world information that changes with the operation of the manipulation unit, an object search unit that searches for an object to be worked on, a grasping range determination unit that uses the manipulation unit to determine the range within which a grasping operation can be performed, a movement procedure generation unit that generates a movement procedure for the movement unit, and a grasping operation generation unit that generates a grasping operation procedure for the manipulation unit (see abstract of Patent document 2). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2017-016359 A [Patent Document 2] JP 2006-159399 A Summary of the Invention [Problem to be solved by the invention]

[0007] Patent Documents 1 and 2 describe a mobile robot system that sets a moving path and a moving procedure for performing a predetermined task, and a target stopping position.

[0008] However, Patent Document 1 and Patent Document 2 do not describe a mobile robot system that determines a target stopping position so that a specified task can be reliably performed even if a positional deviation occurs between a set candidate stopping position and the actual stopping position.

[0009] Furthermore, if the robot is unable to perform a task at its stopping position, it takes time before the robot can begin working due to the need to correct the robot's stopping position or modify the task content.

[0010] Therefore, the present invention provides a mobile robot system that determines a target stopping position by determining whether or not the work can be performed before the work starts and determining an appropriate movement position, so that the specified work can be reliably performed in a short time even if a positional deviation occurs between the set candidate stopping position and the actual stopping position. [Means for solving the problem]

[0011] In order to solve the above-mentioned problems, the mobile robot system of the present invention is a mobile robot system that has a mobile robot that moves to a target stopping position near at least one work object, stops there, and performs a predetermined task on the work object, and has a mobile mechanism and a manipulation unit mounted on the mobile mechanism.

[0012] The mobile robot system has a data management unit that has environmental data related to the structure to be worked on, robot data related to the movable range of the manipulation unit and the movement range of the mobile mechanism, instruction data related to a specified task, and stopping accuracy data that is the stopping accuracy of the mobile mechanism.

[0013] The mobile robot system includes a mobile control unit having a stop position candidate searching unit that uses the environmental data, the robot data, and the teaching data to search for a stop position candidate where a predetermined task can be performed without causing an event that falls outside the movable range of the manipulation unit, an event that falls outside the movable range of the mobile mechanism, or an event in which the manipulation unit and the mobile mechanism interfere with a structure that is the target of the task, and a target stop position determining unit that uses the stop position candidate and the stopping accuracy data to determine a target stop position where the teaching data can be performed from the stop position candidate. The data management unit has a stop accuracy determination unit that determines stop accuracy data, and the stop accuracy determination unit determines the stop accuracy data using movement space data, which is environmental information of a movement space in which the movement mechanism can move and which affects the movement or stopping of the movement mechanism, and self-location estimation accuracy data, which is information on the self-location estimation accuracy and is distance information to a positioning target, which affects the movement or stopping of the movement mechanism. The present invention is characterized by the above. Effect of the Invention

[0014] According to the present invention, it is possible to provide a mobile robot system that determines a target stopping position so as to reliably perform a specified task in a short time even if a positional deviation occurs between a set candidate stopping position and the actual stopping position.

[0015] Problems, configurations and effects other than those described above will become apparent from the following description of the embodiments. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a block diagram illustrating a configuration of a mobile robot system 1 in a first embodiment. [Diagram 2] FIG. 2 is an explanatory diagram illustrating the appearance of a mobile robot 2 in the first embodiment. [Diagram 3] 1 is a flow diagram for explaining a flow F1 until the mobile robot system 1 in the first embodiment determines a target stop position. [Figure 4A] 10 is a flow diagram for explaining a flow F2 from movement / stopping to execution of teaching data 32 in the mobile robot 2 in the first embodiment. FIG. [Figure 4B] FIG. 4B is an explanatory diagram for explaining steps F21 and F22 in FIG. 4A. [Diagram 5] FIG. 2 is an explanatory diagram for explaining a data management unit 3 of the mobile robot system 1 in the first embodiment. [Figure 6] 4 is an explanatory diagram for explaining a stop position candidate searching method of a stop position candidate searching unit 40 in the first embodiment. FIG. [Figure 7] 4 is an explanatory diagram for explaining a target stop position determination method of a target stop position determiner 41 in the first embodiment. FIG. [Figure 8] FIG. 11 is a flow diagram for explaining a flow F11 until the mobile robot system 1 in the first embodiment determines a target stop position. [Figure 9] FIG. 2 is an explanatory diagram for explaining a user interface screen G1 for determining a target stopping position in the mobile robot system 1 in the first embodiment. [Figure 10A]13 is an explanatory diagram illustrating a target stop position determination method of a target stop position determiner 41 in the second embodiment, and is used to explain time-series teaching data 6. FIG. [Figure 10B] 13 is an explanatory diagram illustrating a target stop position determination method of a target stop position determiner 41 in the second embodiment, and explaining a state in the vicinity of a work target 5. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In each drawing, the same reference numerals will be used to refer to substantially the same or similar components. In cases where the explanations of the drawings are repeated, the repeated explanations may be omitted.

[0018] In addition, the drawings and the following examples show embodiments according to the principles of the present invention, and are intended to aid in understanding the present invention, but are not intended to be used to interpret the present invention in a restrictive manner. The drawings and the following examples are merely typical examples, and are not intended to limit the scope of the claims in any sense.

[0019] The present invention is not limited to the following examples, but includes various modified examples. The following examples are specifically described in order to explain the present invention in an easily understandable manner, and the present invention is not necessarily limited to those having all of the configurations described.

[0020] Also, a part of the configuration of one embodiment can be replaced with a part of the configuration of another embodiment. Also, the configuration of another embodiment can be added to the configuration of one embodiment. Also, a part of the configuration of each embodiment can be deleted, and a part of another configuration can be added or replaced with a part of another configuration. EXAMPLES

[0021] First, the configuration of a mobile robot system 1 in the first embodiment will be described.

[0022] FIG. 1 is a block diagram illustrating a configuration of a mobile robot system 1 according to a first embodiment.

[0023] The mobile robot system 1 includes a mobile robot 2, a data management unit 3, and a movement control unit 4.

[0024] The mobile robot 2 has a moving mechanism 21 and a manipulation unit 20 mounted on the moving mechanism 21. The mobile robot 2 moves to a target stop position near a work target area near at least one work target 5 by the moving mechanism 21, stops there, and executes a predetermined task on the work target 5 by the manipulation unit 20.

[0025] The data management unit 3 has environmental data 30 having information on the size and position of the structure 50 of the work target 5, robot data 31 (robot data 31 having the workable area of ​​the mobile robot 2) having information such as the size and moving range of the manipulation unit 20 and the size and moving range of the mobile mechanism 21, instruction data 32 describing information related to a specified task, and stopping accuracy data 33 having information on the stopping accuracy of the mobile mechanism 21.

[0026] Information on the size and position of the structure 50 of the work object 5 contained in the environmental data 30 is expressed, for example, by 3D model data of the structure 50 of the work object 5, or a file describing the shape and position of the structure 50 of the work object 5 in text format.

[0027] Information included in the robot data 31, such as the size and movable range of the manipulation unit 20, and the size and moving range of the moving mechanism 21, is expressed, for example, by 3D model data of the mobile robot 2, or a file describing the shape and configuration of the mobile robot 2 in text format.

[0028] The information on the predetermined task described in the teaching data 32 is expressed, for example, by a chronological arrangement of hand position and orientation information of the end effector 200 installed in the manipulation unit 20, or a file in which the work procedure is described in text format. The teaching data 32 is output to the manipulation unit 20, and the end effector 200 installed in the manipulation unit 20 executes the predetermined task on the work object 5 based on the teaching data 32.

[0029] The information on the stopping accuracy of the moving mechanism 21 included in the stopping accuracy data 33 is expressed, for example, by a uniform numerical value in all directions that spreads in a circle around the stopping position, a mathematical formula, a map, etc. The stopping accuracy data 33 may be expressed, for example, by a grid map 43 using cells 430.

[0030] The stopping accuracy of the moving mechanism 21 included in the stopping accuracy data 33 comprehensively includes factors that cause positional deviation between a set candidate stopping position and an actual stopping position that occurs when the moving robot 2 moves to any point within the moving space, such as the control accuracy of the moving mechanism 21, the slipperiness of the moving mechanism 21 on the floor surface (movement accuracy of the moving part), and the positioning accuracy (detection accuracy of the detection part) of the position sensor (particularly, in Example 1, the position sensor mounted on the moving mechanism 21) used to estimate the moving mechanism 21's own position within the moving space.

[0031] For this reason, it is preferable that the stopping accuracy data 33 is identified in advance in the same environment and in the same system.

[0032] The movement control unit 4 has a stop position candidate searching unit 40 that searches for an area where a specified task can be performed (hereinafter referred to as a workable area) in the work target area near the work target 5 and searches for a stop position candidate (stop position candidate information) so that no events occur that fall outside the movable range of the manipulation unit 20, no events that fall outside the movable range of the mobile mechanism 21, or events in which the manipulation unit 20 and the mobile mechanism 21 interfere with the structure 50 of the work target 5, and a target stop position determination unit 41 that takes into account the stopping accuracy data 33 and determines a target stop position (target stop position information) from the stop position candidates so that the mobile robot 2 can reliably stop in the workable area (area including the work performance area described later).

[0033] The stop position candidate search unit 40 uses the environment data 30, the robot data 31, and the teaching data 32 to search for a workable area and to search for stop position candidates (workable areas).

[0034] The target stop position determination unit 41 uses the stop position candidates acquired from the stop position candidate search unit 40 and the stop accuracy data 33 to determine a target stop position, and outputs the target stop position to the moving mechanism 21.

[0035] Next, the external appearance of the mobile robot 2 in the first embodiment will be described.

[0036] FIG. 2 is an explanatory diagram illustrating the appearance of the mobile robot 2 in the first embodiment.

[0037] The mobile robot 2, which is the moving and movable part of the mobile robot system 1, has a mobile mechanism 21 equipped with actuators and position sensors and having one or more wheels, and a manipulation unit 20 mounted on the mobile mechanism 21, equipped with actuators and position sensors, and having multiple joints.

[0038] The position sensor mounted on the moving mechanism 21 and the position sensor mounted on the manipulation unit 20 are used to estimate the self-position of the moving mechanism 21 in the movement space. In the first embodiment, the position sensor is mounted on the moving mechanism 21 and the manipulation unit 20, but may be mounted on the moving mechanism 21 or the manipulation unit 20.

[0039] The moving mechanism 21 has a robot control unit 22 that controls the wheels and joints.

[0040] The manipulation unit 20 has an end effector 200 that grasps a grasp target 51 in the work object 5, and a relative positional relationship acquisition unit 23 that recognizes the work object 5 and acquires a relative positional relationship (relative positional relationship information) between the end effector 200 and the work object 5. In the first embodiment, the relative positional relationship acquisition unit 23 has a function of a position sensor mounted on the manipulation unit 20.

[0041] In other words, the manipulation unit 20 has a relative positional relationship acquisition unit 23 that recognizes the work object 5 after the moving mechanism 21 stops at the target stopping position and acquires the relative positional relationship between the manipulation unit 20 (the moving robot 2 in a broad sense, the end effector 200 in a narrow sense) and the work object 5.

[0042] The data management unit 3 and / or the movement control unit 4 may be installed inside the mobile robot 2, particularly in the robot control unit 22, or may be installed outside the mobile robot 2.

[0043] Next, a flow F1 until the mobile robot system 1 in the first embodiment determines a target stop position will be described.

[0044] FIG. 3 is a flow diagram illustrating a flow F1 until the mobile robot system 1 in the first embodiment determines a target stop position.

[0045] In step F10, the mobile robot 2 to be used is prepared, and at the same time, the robot data 31 and the stopping accuracy data 33 are acquired.

[0046] In step F11, the arrangement of the object to be grasped 51 in the work object 5 is determined, and at the same time, the environmental data 30 is acquired.

[0047] In step F12, the arrangement of the object to be grasped 51 in the work object 5 is determined, and at the same time, with the environmental data 30 acquired, teaching data 32 is created to instruct the mobile robot 2 on the arrangement of the structures 50 in the work object 5 and the arrangement of the object to be grasped 51 in the work object 5.

[0048] It should be noted that steps F10, F11, and F12 are steps that are processed by the user (the range of processing by the user).

[0049] In step F13, the stop position candidate search unit 40 acquires the environmental data 30, the robot data 31, and the teaching data 32, and then uses the environmental data 30, the robot data 31, and the teaching data 32 to search for the workable area and search for stop position candidates.

[0050] In step F14, the target stop position determining unit 41 determines a target stop position using the stop position candidates and the stopping accuracy data 33, and moves the mobile robot 2.

[0051] Steps F13 and F14 are steps that are processed by the movement control unit 4 (the range of processing by the movement control unit 4), and are steps that are processed by software before the mobile robot 2 moves.

[0052] As a result, according to Example 1, it is possible to ensure that the target stopping position is determined in advance (before the mobile robot 2 moves) and the teaching data 32 is executed, compared to a case in which the work object 5 is detected and the set stopping position candidate is corrected after the mobile robot 2 has moved, thereby shortening the operating time of the mobile robot 2.

[0053] Next, a flow F2 from movement / stopping to execution of the teaching data 32 (a procedure for executing the task of the teaching data 32 after the mobile robot 2 is stopped) in the mobile robot 2 in the first embodiment will be described.

[0054] FIG. 4A is a flow diagram for explaining a flow F2 from movement / stopping to execution of the teaching data 32 in the mobile robot 2 in the first embodiment.

[0055] In step F20, the moving mechanism 21 moves to the determined target stop position and stops at the determined target stop position.

[0056] In step F21, the relative positional relationship between the end effector 200 and the work object 5 is acquired by the relative positional relationship acquisition unit 23.

[0057] In step F22, based on the acquired relative positional relationship, the teaching data 32 is converted into data executable by the mobile robot 2. That is, based on the acquired relative positional relationship, the teaching data conversion unit 34 installed in the data management unit 3 converts the teaching data 32 into data (robot coordinate reference data) expressed based on the robot coordinate system (coordinate system fixed to the mobile robot 2). In this way, the data management unit 3 has the teaching data conversion unit 34 that converts the teaching data 32 into data based on the robot coordinate system based on the acquired relative positional relationship.

[0058] In step F23, the converted teaching data 32 is executed by the manipulation unit 20. This enables the manipulation unit 20 to execute a predetermined task.

[0059] Next, steps F21 and F22 in FIG. 4A will be described.

[0060] FIG. 4B is an explanatory diagram for explaining steps F21 and F22 in FIG. 4A.

[0061] The work target 5 has a structure 50 and an object to be grasped 51 .

[0062] The teaching data 32 is expressed as a point locus of the position and orientation of the tip (hand tip) of the end effector 200 when the end effector 200 grasps the grasp target 51, that is, a teaching data locus 320.

[0063] The teaching data 32 is data expressed based on a coordinate system (work object coordinate system 52) fixed to the work object 5, and the teaching data trajectory 320 is stored in the data management unit 3 as hand position and posture information of the end effector 200 based on the work object coordinate system 52, which is a coordinate system fixed to the work object 5.

[0064] In step F21, the relative positional relationship acquisition unit 23 acquires the relative positional relationship between the robot coordinate system 24, which is a coordinate system fixed to the mobile robot 2, and the work target coordinate system 52.

[0065] In step F22, based on the acquired relative positional relationship, the teaching data conversion unit 34 converts the teaching data 32 into data based on the robot coordinate system 24, which is executable by the mobile robot 2. Then, the joint angles of the manipulation unit 20 are controlled so that the tip (hand tip) of the end effector 200 overlaps with the position and posture of the converted data. This enables the end effector 200 to follow the teaching data trajectory 320.

[0066] Next, the data management unit 3 of the mobile robot system 1 in the first embodiment will be described.

[0067] FIG. 5 is an explanatory diagram illustrating the data management unit 3 of the mobile robot system 1 in the first embodiment.

[0068] The data management unit 3 has a stopping accuracy determination unit 37 that determines the stopping accuracy data 33 .

[0069] The cause of the positional deviation between the set stop position candidate and the actual stop position, particularly the positional deviation due to slippage of the moving mechanism 21 on the floor surface, may differ depending on the position in the moving space. Also, the positioning accuracy of the position sensor used to estimate the self-position in the moving space may change depending on the position in the moving space.

[0070] Therefore, in the data management unit 3, the stopping accuracy determination unit 37 determines the stopping accuracy data 33 using the movement space data 35 and the self-position estimation accuracy data 36 so that the stopping accuracy data 33 can be varied depending on the position within the movement space.

[0071] The movement space data 35 is environmental information of the movement space in which the movement mechanism 21 can move, which affects the movement or stopping of the movement mechanism 21 at any position within the movement space, and is expressed, for example, by a mathematical formula or map of the amount of slippage of the movement mechanism 21 against the floor surface within the movement space, or information showing the condition of the floor surface.

[0072] The self-location estimation accuracy data 36 is information on the self-location estimation accuracy that affects the movement or stopping of the moving mechanism 21 at a position within an arbitrary moving space, estimated by the self-location estimation unit 42 installed in the moving control unit 4 (for example, the distance to a positioning target such as a wall or pillar of a workroom), and is expressed, for example, by a mathematical formula or map of the self-location estimation accuracy, or by information on the position sensor used.

[0073] In this manner, the movement control unit 4 has a self-position estimating unit 42 that estimates the self-position and orientation of the mobile robot 2 within a movement space, and the self-position estimating unit 42 estimates the self-position estimation accuracy data 36.

[0074] This makes it possible to reflect changes in the stopping accuracy of the moving mechanism 21 at positions within the movement space in the determination of the target stopping position.

[0075] Furthermore, by covering the floor surface within the movement space with tiles or the like having a uniform floor surface condition, and by separately placing a positioning target within the movement space that serves as a hint for estimating the self-position, it is possible to eliminate changes in the stopping accuracy of the movement mechanism 21 depending on the position within the movement space.

[0076] Next, a method of searching for stop position candidates by the stop position candidate searching unit 40 in the first embodiment will be described.

[0077] FIG. 6 is an explanatory diagram for explaining a stop position candidate searching method of the stop position candidate searching unit 40 in the first embodiment.

[0078] When searching for candidate stopping positions, the candidate stopping position search unit 40 determines whether or not a specified task can be performed (whether or not the task can be completed) for each cell 430 (search point having a constant width in the front, back, left and right directions) spaced at regular intervals (grid-like) in the front, back, left and right directions in the grid map 43 near the work object area 431 where the work object 5 is located, and searches for candidate stopping positions.

[0079] In other words, when searching for stopping position candidates, the stopping position candidate search unit 40 uses a grid map 43 that is near a work object area 431 near the work object 5 and is divided into multiple cells 430 at regular intervals in the front, back, left and right directions, and determines whether or not work can be performed for each cell 430 (a fixed search width in the front, back, left and right directions) and searches for stopping position candidates (cells 430 in which work can be performed).

[0080] The mobile robot 2 is stopped in a certain cell 430 near the work target area 431, and the end effector 200 installed in the manipulation unit 20 is actually operated based on the teaching data 32. Then, when the end effector 200 operates (when the teaching data 32 can be created), this cell 430 (the first stop position candidate searched) is set as a teaching point 4300, and is set as the starting point for searching for stop position candidates. Starting from the teaching point 4300, stop position candidates are searched for in the cells 430 on the front, back, left and right sides.

[0081] When searching for a candidate stopping position, the mobile robot 2 is stopped at a certain cell 430, and a candidate stopping position is searched for based on the teaching data 32, where the cell 430 is within the operating range of the end effector 200 (within the movable range of the manipulation unit 20) and where the end effector 200 (manipulation unit 20) does not interfere with the structure 50 of the work target 5, as a workable point 4301 that is a workable area. Note that the teaching point 4300 is the first workable point 4301.

[0082] Similarly, a stop position candidate is searched for in cell 430A (defined for convenience of explanation) in the four directions (adjacent to the front, rear, left and right) of the teaching point 4300. Furthermore, a stop position candidate is searched for in cell 430B (defined for convenience of explanation) adjacent to the four directions of cell 430A, and further a stop position candidate is searched for in cell 430C (defined for convenience of explanation) adjacent to the four directions of cell 430B.

[0083] Furthermore, if a cell 430 for which a stop position candidate is searched is outside the operating range of the end effector 200 (outside the movable range of the manipulation unit 20), or if the end effector 200 (manipulation unit 20) interferes with the structure 50 of the work target 5, it is determined to be an inoperable point, and the search for stop position candidates is terminated for the cell 430 and beyond. Note that an arbitrary range may be specified for the cells 430 in the vicinity of the work target area 431, and the search for stop position candidates may be terminated if the cell is outside that range.

[0084] In this manner, a search is made for stopping position candidates that are a set of multiple workable points 4301 (a set of multiple cells 430).

[0085] By setting the teaching point 4300, where the execution of a specified task is guaranteed, as the starting point for searching for candidate stopping positions and searching for candidate stopping positions, it is possible to search for candidate stopping positions with less computational cost than searching all of the work object areas 431 in the vicinity of the work object 5.

[0086] Next, a method for determining a target stop position by the target stop position determiner 41 in the first embodiment will be described.

[0087] FIG. 7 is an explanatory diagram for explaining a target stop position determination method of the target stop position determiner 41 in the first embodiment.

[0088] For the stop position candidates which are a set of a plurality of workable points 4301, the target stop position determination unit 41 takes into consideration the stopping accuracy data 33 and acquires a work execution guaranteed point 4302 where the execution (performance) of a predetermined work is guaranteed.

[0089] In addition, when the work performance guarantee point 4302 is acquired as one cell 430, that one cell 430 is determined as the target stopping position, and when the work performance guarantee point 4302 is acquired as multiple cells 430, the center of gravity position 432 of the multiple cells 430 (the work performance area which is a collection of the multiple work performance guarantee points 4302) is determined as the target stopping position.

[0090] As a result, at the task execution guaranteed point 4302, the cell 430 with the highest margin of accuracy in stopping the moving mechanism 21 can be determined as the target stopping position.

[0091] Moreover, it is preferable that the interval between the cells 430 in the grid map 43 is a value that depends on the stopping accuracy data 33. For example, when the stopping accuracy of the moving mechanism 21 is set as a circle of ±R mm, it is preferable that the interval between the cells 430 is set to R mm or more.

[0092] Then, when acquiring a work execution guarantee point 4302, if a cell 430 in eight directions (front, back, left, right, front left, front right, rear left, rear right) of a certain workable point 4301 is also a workable point 4301, then that cell 430 can be acquired as a work execution guarantee point 4302. This makes it possible to acquire a work execution guarantee point 4302 with low calculation cost.

[0093] Next, a flow F11 until the mobile robot system 1 in the first embodiment determines a target stop position will be described.

[0094] FIG. 8 is a flow diagram for explaining a flow F11 until the mobile robot system 1 in the first embodiment determines a target stop position.

[0095] Here, a flow F11 is shown for the case where the target stop position cannot be determined in step F14 of the flow F1 shown in FIG.

[0096] In step F141, the target stop position determination unit 41 judges whether or not the target stop position can be determined. That is, it judges whether or not the task execution guarantee point 4302 can be acquired. If the target stop position can be determined (YES), the process proceeds to step F142, and if the target stop position cannot be determined (NO), the process proceeds to step F143.

[0097] Then, in step F141, if it is determined that the target stop position can be determined (YES), the target stop position determining unit 41 determines the target stop position and moves the mobile robot 2 in step F142.

[0098] Incidentally, in step F141, when it is judged that the target stop position cannot be determined (NO), the correction method calculation unit 410 set in the target stop position determination unit 41 corrects at least one of the influencing factors that affect the determination of the target stop position, such as the configuration of the manipulation unit 20, the condition of the floor surface, the arrangement of the structure 50 of the work target 5, and the teaching data 32, or displays the correction to the user. In other words, at least one of the influencing factors is corrected or the correction is displayed to the user so that a target stop position that satisfies the conditions of the target stop position determination unit 41 exists.

[0099] The correction method calculation unit 410 corrects the influencing factors using the following correction methods, for example, or displays the corrections to the user. Correction method (1): Change the configuration of the manipulation unit 20 so as to expand the range of motion of the manipulation unit 20. Correction method (2): Change the position sensor and change the floor conditions so as to improve the stopping accuracy of the moving mechanism 21. Correction method (3): Change the arrangement of the structure 50 of the work target 5 so that the manipulation unit 20 can operate easily. Correction method (4): Change the teaching data 32 so that it is less likely to interfere with the structure 50 of the work target 5.

[0100] Modifications such as modification method (1) and modification method (2) require changes to the hardware configuration of the mobile robot 2. For this reason, modifications such as modification method (3) and / or modification method (4) are preferable. This can reduce the number of user processing steps required for modification.

[0101] Then, in step F141, if it is determined that the target stop position cannot be determined (NO), in step F143, the correction method calculation unit 410 displays the correction contents of the influencing factors to the user, and the process returns to step F10.

[0102] It should be noted that, with regard to the modification of the influencing factors, the user modifies at least one of steps F10, F11, and F12 based on the modification content of the displayed influencing factors.

[0103] In addition, the correction of the influencing factors may be automatically performed by software processing. For example, when changing the teaching data 32 (changing the positions of some data points of the teaching data 32), the data points may be automatically changed. This can eliminate the need for the user to go back and forth, thereby reducing the number of processing steps required by the user.

[0104] Next, a user interface screen G1 for determining a target stop position in the mobile robot system 1 in the first embodiment will be described.

[0105] FIG. 9 is an explanatory diagram for explaining a user interface screen G1 for determining a target stop position in the mobile robot system 1 in the first embodiment.

[0106] The user interface screen (display unit) G1 displays a grid map 43, a map coordinate system G100, and a target stop position selection cursor G101, and has a map display unit G10 that displays the vicinity of the work object 5 and the target stop position, a teaching data name display unit G11 that displays the name of the teaching data 32, a cursor movement button G12 that moves the target stop position selection cursor G101 and enables selection of the target stop position, a cursor position information display unit G13 that displays position information of the target stop position selection cursor G101, and a target stop position setting button G14 that sets the target stop position.

[0107] The target stop position selection cursor G101 selects only the task execution guaranteed point 4302, and the user can determine any task execution guaranteed point 4302 as the target stop position.

[0108] Generally, when a position shift occurs between the set candidate stopping position and the actual stopping position of the mobile robot system 1, and the teaching data 32 cannot be executed, an event may occur in which the mobile mechanism 21 falls outside its moving range, the manipulation unit 20 falls outside its movable range, or the manipulation unit 20 or mobile mechanism 21 interferes with the structure 50 of the work target 5 when performing work.

[0109] For this reason, the mobile robot system 1 described in Example 1 searches for a workable area in the work target area 431 near the work target 5 based on the teaching data 32, robot data 31, and environmental data 30, where there are no events occurring that fall outside the movement range of the mobile mechanism 21, that fall outside the movable range of the manipulation unit 20, or that cause the manipulation unit 20 and the mobile mechanism 21 to interfere with the structure 50 of the work target 5, and searches for candidate stopping positions. Taking into account the stopping accuracy data 33, which is the stopping accuracy of the mobile mechanism 21, the candidate stopping positions, the mobile robot system 1 determines a target stopping position that allows the mobile robot 2 to reliably stop within the work execution area (area inside the workable area).

[0110] In other words, according to the first embodiment, even if a positional deviation occurs between the set candidate stop position and the actual stop position, the target stop position can be determined so that the specified task can be reliably executed.

[0111] Moreover, according to the first embodiment, the target stop position can be determined so that a predetermined task can be reliably performed without depending on the movement accuracy of the moving part or the detection accuracy of the detecting part.

[0112] Moreover, according to the first embodiment, the time required for the mobile robot 2 to converge to the target stop position can be shortened, and the operating time of the mobile robot 2 can be shortened.

[0113] Furthermore, according to the first embodiment, even if the area in which a predetermined task is to be performed is particularly small, the mobile robot 2 can easily stop in that area.

[0114] As a result, the present system can reliably perform the specified task in a short time even if a position deviation occurs between the set candidate stopping position and the actual stopping position. EXAMPLES

[0115] Next, a method for determining a target stop position by the target stop position determiner 41 in the second embodiment will be described.

[0116] FIG. 10A is an explanatory diagram illustrating the time series teaching data 6 in the target stop position determination method of the target stop position determination unit 41 in Example 2, and FIG. 10B is an explanatory diagram illustrating the state in the vicinity of the work object 5 in the target stop position determination method of the target stop position determination unit 41 in Example 2.

[0117] In addition, in the second embodiment, a description will be given of the differences from the first embodiment. The parts not described in the second embodiment are the same as those in the first embodiment.

[0118] 10A shows time-series teaching data 6 having at least two or more teaching data 32 for one work target 5. In the second embodiment, the data management unit 3 has, for example, three teaching data 32, and the three teaching data 32 are executed as the time-series teaching data 6 in the order of teaching data A61, teaching data B62, and teaching data C63.

[0119] FIG. 10B shows a state in the vicinity of one work object 5, in which workable areas are searched for the teaching data A61, teaching data B62, and teaching data C63 included in the time-series teaching data 6.

[0120] Figure 10B shows a workable area 610 for taught data A61 and a target stopping position 611 determined therefrom, a workable area 620 for taught data B62 and a target stopping position 621 determined therefrom, and a workable area 630 for taught data C63 and a target stopping position 631 determined therefrom.

[0121] In this manner, when the time-series teaching data 6 is executed, the target stop positions are determined for all teaching data included in the time-series teaching data 6 (teaching data A61, teaching data B62, teaching data C63).

[0122] In other words, when the teaching data 32 is multiple time-series teaching data (time-series teaching data 6) for a specified task, the target stop position determination unit 41 determines a target stop position for each of the teaching data (teaching data A61, teaching data B62, teaching data C63).

[0123] When executing a predetermined task, the position of the mobile robot 2 may be changed to a target stop position for each piece of teaching data, and each piece of teaching data may be executed at each target stop position.

[0124] In addition, when performing a specified task, if the workable areas (candidate stopping positions) in successive teaching data overlap and the same (single) target stopping position can be determined for the overlapping workable areas (candidate stopping positions), each teaching data may be executed at this same target stopping position.

[0125] In other words, the target stop position determination unit 41 determines the same target stop position for areas (workable areas) forming stop position candidates that overlap (are common) in multiple time-series teaching data, at least two consecutive teaching data, and for the areas (workable areas) forming the overlapping (common) stop position candidates.

[0126] For example, in the second embodiment, the workable area of ​​the taught data A61 and the workable area of ​​the taught data B62 overlap, and for the overlapping workable areas, the stopping accuracy data 33, which is the stopping accuracy of the moving mechanism 21, is taken into consideration to determine a common target stopping position 64 for the taught data A61 and the taught data B62. In this case, the mobile robot 2 first moves to the target stopping position 64 and executes the taught data A61 and the taught data B62, and then moves to the target stopping position 631 and executes the taught data C63.

[0127] Moreover, the teaching data may be corrected so that all teaching data included in the time-series teaching data 6 can be executed using a common target stopping position.

[0128] In this case, the teaching data to be modified is selected so that the workable areas of all the teaching data overlap, a target stop position can be determined for the overlapping workable areas, and the number of teaching data to be modified is minimized, and the selected teaching data is modified by the modification method calculation unit 410 in the same manner as in Example 1.

[0129] However, since the correction methods (1), (2), and (3) shown in the first embodiment affect the workable area of ​​all teaching data, it is preferable to perform the correction using the correction method (4).

[0130] In other words, the target stop position determination unit 41 has a correction method calculation unit 410 that corrects at least one of the influencing factors that affect the determination of the target stop position, and when correcting teaching data, the correction method calculation unit 410 selects the teaching data to be corrected so that the number of teaching data to be corrected is minimized.

[0131] Then, for each piece of teaching data, the teaching data is corrected based on range information of the workable area of ​​each piece of teaching data so that the workable areas of all the teaching data overlap.

[0132] In other words, when there is no target stop position that satisfies the conditions of the target stop position determination unit 41 for all the teaching data, the target stop position determination unit 41 calculates the range of stop position candidates for each teaching data, and selects the teaching data to be corrected based on the calculated range of stop position candidates so that there is a target stop position that satisfies the conditions of the target stop position determination unit 41 and so that the number of teaching data to be corrected is minimized.

[0133] For example, in the second embodiment, in order to make the workable areas of all the teaching data overlap based on the range information of the workable areas of each teaching data, only the teaching data C63 needs to be corrected. After correcting only the teaching data C63, the mobile robot 2 moves to a common target stop position for all the teaching data and executes all the teaching data.

[0134] According to the second embodiment, even if there are a plurality of teaching data to be executed, it is possible to determine the target stop position so that a predetermined task can be executed reliably in a short time. [Explanation of symbols]

[0135] 1 Mobile robot system, 2 Mobile robot, 20 Manipulation unit, 200 End effector, 21 Mobile mechanism, 22 Robot control unit, 23 Relative position relationship acquisition unit, 24 Robot coordinate system, 3 Data management unit, 30 Environmental data, 31 Robot data, 32 Teaching data, 320 Teaching data trajectory, 33 Stopping accuracy data, 34 Teaching data conversion unit, 35 Movement space data, 36 Self-location estimation accuracy data, 37 Stopping accuracy determination unit, 4 Movement control unit, 40 Stopping position candidate search unit, 41 Target stopping position determination unit, 410 Correction method calculation unit, 42 Self-location estimation unit, 43 Grid map, 430, cell, 4300, teaching point, 4301, workable point, 4302, guaranteed work execution point, 431, work target area, 432, center of gravity position, 5, work target, 50, structure, 51, object to be grasped, 52, work target coordinate system, 6, time-series teaching data, 61, teaching data A, 610, workable area of ​​teaching data A, 611, target stopping position of teaching data A, 62, teaching data B, 620, workable area of ​​teaching data B, 621, target stopping position of teaching data B, 63, teaching data C, 630, workable area of ​​teaching data C, 631, target stopping position of teaching data C, 64, common target stopping position.

Claims

1. A mobile robot system having a mobile robot that moves to a target stop position near at least one work object, stops there, and executes a predetermined task on the work object, the mobile robot having a moving mechanism and a manipulation unit mounted on the moving mechanism, a data management unit having environmental data on the structure to be worked on, robot data on a movable range of the manipulation unit and a movable range of the mobile mechanism, teaching data on the predetermined work, and stopping accuracy data which is a stopping accuracy of the mobile mechanism; a movement control unit having a stop position candidate searching unit which uses the environmental data, the robot data, and the teaching data to search for a stop position candidate at which the specified task can be performed and which does not cause an event that falls outside the movable range of the manipulation unit, an event that falls outside the movable range of the mobile mechanism, or an event in which the manipulation unit and the mobile mechanism interfere with the structure to be worked on; and a target stop position determining unit which uses the stop position candidate and the stopping accuracy data to determine a target stop position at which the teaching data can be performed from the stop position candidate; having The data management unit has a stopping accuracy determination unit that determines the stopping accuracy data, and the stopping accuracy determination unit determines the stopping accuracy data using moving space data, which is environmental information of a moving space in which the moving mechanism can move and which affects the movement or stopping of the moving mechanism, and self-position estimation accuracy data, which is information on self-position estimation accuracy that affects the movement or stopping of the moving mechanism and is distance information to a positioning target.

2. 2. The mobile robot system according to claim 1, A mobile robot system, wherein the manipulation unit has a relative positional relationship acquisition unit that recognizes the work object and acquires a relative positional relationship between the manipulation unit and the work object.

3. 3. The mobile robot system according to claim 2, A mobile robot system characterized in that the data management unit has a teaching data conversion unit that converts the teaching data based on a coordinate system fixed to the work object into data based on a robot coordinate system based on the relative positional relationship.

4. 2. The mobile robot system according to claim 1, A mobile robot system characterized in that the stop position candidate search unit uses a plurality of cells in the vicinity of the work object, determines for each cell whether or not the work can be completed, and searches for stop position candidates.

5. A mobile robot system as described in claim 4, The target stopping position determination unit takes into account the stopping accuracy data for the stopping position candidates, obtains a work execution guarantee point at which the execution of the specified task is guaranteed, and when multiple work execution guarantee points are obtained, determines the center of gravity position as the target stopping position.

6. 2. The mobile robot system according to claim 1, A mobile robot system comprising: a display unit that displays the vicinity of the work object and the target stopping position.

7. 2. The mobile robot system according to claim 1, A mobile robot system, wherein the target stop position determination unit has a correction method calculation unit that corrects at least one of the influencing factors that affect the determination of the target stop position.

8. 2. The mobile robot system according to claim 1, A mobile robot system characterized in that, when the teaching data is a plurality of time-series teaching data for the specified task, the target stop position determination unit determines the target stop position for all of the teaching data.

9. A mobile robot system as described in claim 8, A mobile robot system, characterized in that the target stop position determination unit determines the same target stop position for the overlapping stop position candidates in time-series teaching data.

10. A mobile robot system as described in claim 9, The target stop position determination unit has a correction method calculation unit that corrects at least one of the influencing factors that affect the determination of the target stop position, A mobile robot system, wherein the correction method calculation unit, when correcting the teaching data, selects the teaching data to be corrected so as to minimize the number of teaching data to be corrected.

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