JP2008134744A - Autonomous moving device group control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the operation efficiency of an autonomous moving device group control system by attaining early detection and solving of a deadlock state through simple structure. <P>SOLUTION: Each autonomous moving device 1 of this system 1 includes a position information acquisition part for acquiring its own position information and a communication part for transmitting the position information to a central control unit 3 and receiving a destination. The central control unit 3 includes a communication part for receiving the position information from the moving device 2 and transmitting the destination; a deadlock determination part for determining the deadlock state for a plurality of autonomous moving devices 2 based on the position information; and a deadlock solving part 54 for giving an instruction to change the destination of at least one of the autonomous moving devices 2 laid in the deadlock state. Since the deadlock determination part determines and detects a state where the autonomous moving device stays within a predetermined distance longer than a predetermined time as the deadlock state, early detection and solving of the deadlock state can be attained with simple and easy determination, and the operation efficiency of the system can be thus improved. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an autonomous mobile device group control system that controls a plurality of autonomous mobile devices and performs transportation by the autonomous mobile device.

  Conventionally, there is a system including a plurality of autonomous mobile devices and a central control device that monitors each autonomous mobile device and controls its operation. When operating an autonomous mobile device group in such a system, it is necessary to prevent the collision of autonomous mobile devices and the occurrence of movement obstruction, and various ideas have been made.

  For example, as shown in FIG. 15, a passing point called a node n is set in an operation area limited by a wall W, and two autonomous vehicles moving on a moving route formed by connecting these nodes n A mobile device 2 is assumed. Central control in which each autonomous mobile device 2 grasps that each other's movement paths intersect when trying to move simultaneously in the directions indicated by arrows a and b, and moves one autonomous mobile device 2 first according to priority An autonomous mobile device group control system including a device is known (for example, see Patent Document 1).

  In addition, a system that determines the possibility of collision based on a finite number of subgoal data (nodes) set in each movement path and does not predict the intersection of movement paths, and changes the movement path so as to avoid collision Is known (see, for example, Patent Document 2).

In addition, in order to prevent collision with other autonomous mobile devices and moving objects and running disturbance, a stop signal is received from the central control device or a stop signal is detected based on the surrounding situation. A system that retreats to the ground and yields a moving route is known (for example, see Patent Document 3).
JP 2006-113687 A JP 2006-133863 A JP 2003-140747 A

  However, in the autonomous mobile device group control system as shown in Patent Documents 1, 2, and 3 described above, collision avoidance and avoidance of travel disturbance to other mobile devices are described. It does not describe how to efficiently operate the system by detecting and eliminating a deadlock state that has occurred for some reason during avoidance processing (forced stop) or obstacle avoidance processing. As shown in FIG. 17, the deadlock state is a state in which a plurality of autonomous mobile devices 2 are gathered in one place and are unable to move due to obstructing each other's path. Become.

  An object of the present invention is to solve the above problems, and to provide an autonomous mobile device group control system capable of early detection and elimination of a deadlock state with a simple configuration and realizing improvement in system operation efficiency. And

  In order to achieve the above object, the invention of claim 1 is directed to a plurality of autonomous mobile devices that autonomously move to a destination while generating a route to the destination and avoiding an obstacle, and each of the autonomous mobile devices. An autonomous mobile device group control system comprising: a central control device that directs a destination to the autonomous mobile device group control system, wherein the autonomous mobile device recognizes its location and acquires its location information; and the location information A communication unit that transmits the position information acquired by the acquisition unit to the central control device or receives an instruction including a destination from the central control device, the central control device from the autonomous mobile device A communication unit that receives location information or transmits an instruction including a destination to the autonomous mobile device, and a plurality of autonomous mobile devices stay within a predetermined distance from each other for a predetermined time based on the received location information A deadlock determination unit that determines that these autonomous mobile devices are in a deadlock state with each other, and a plurality of autonomous mobile devices are determined to be in a deadlock state by the deadlock determination unit A deadlock elimination unit that issues an instruction to change the destination of at least one autonomous mobile device among the autonomous mobile devices that are sometimes in a deadlock state.

  According to a second aspect of the present invention, in the autonomous mobile device group control system according to the first aspect, the deadlock determination unit determines a mutual deadlock state for two autonomous mobile devices.

  According to a third aspect of the present invention, in the autonomous mobile device group control system according to the first or second aspect, the deadlock canceling unit has no obstacle on a route along which the autonomous mobile device that changes the destination moves. In this way, the destination is set.

  According to a fourth aspect of the present invention, in the autonomous mobile device group control system according to the first or second aspect, the deadlock canceling unit is configured such that the traveling direction of the autonomous mobile device that changes the destination is the original traveling direction. Sets the destination so that it is on the opposite side.

  According to the first aspect of the present invention, the state of staying within a predetermined distance for a longer time than the predetermined time is detected as a deadlock state. Therefore, the detection of the deadlock state is simple and easy, and the deadlock state is early. Detection and resolution can be realized, and system operation efficiency can be improved. That is, when the destination of at least one autonomous mobile device is changed, other autonomous mobile devices can move, and the distance between the plurality of autonomous mobile devices is increased. The movement to the ground can be resumed.

  According to the second aspect of the present invention, it is only necessary to sequentially determine two units at a time, and it is easy to determine and eliminate the deadlock state, thereby speeding up the processing. Even if three or more autonomous mobile devices are in a deadlock state at the same place, the deadlock state can be resolved by processing for every two devices.

  According to invention of Claim 3, when heading to the destination used as a waiting point, it can be moved quickly and smoothly without trouble.

  According to the fourth aspect of the present invention, it is easy to select a destination as a standby point, and the deadlock state can be surely eliminated rather than moving forward.

  Hereinafter, an autonomous mobile device group control system according to an embodiment of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 shows a configuration of an autonomous mobile device group control system 1 according to the first embodiment, and FIGS. 2 and 3 show block configurations of an autonomous mobile device 2 and a central control device 3 in the control system 1, respectively. As shown in FIG. 1, the autonomous mobile device group control system 1 includes a plurality of autonomous mobile devices 2 that autonomously move to an instructed destination, and a central control device 3 that instructs each of the autonomous mobile devices 2 to the destination. The deadlock state generated between the autonomous mobile devices 2 is eliminated using the deadlock elimination unit 54 and the like of the central control device 3.

  As shown in FIG. 2, the autonomous mobile device 2 includes a communication unit 21 that communicates with the central control device 3, an environment recognition unit 22 that recognizes an external environment around itself and acquires environment information, a wheel, and the like. A traveling means 23 for traveling and a traveling control means 24 are provided.

  The communication unit 21 performs communication by wireless communication, transmits the position information acquired by the position information acquisition unit 45 described later to the central control device 3, or receives an instruction including the destination from the central control device 3.

  The environment recognizing means 22 includes an imaging device such as a laser radar, an ultrasonic sensor, a camera, and the like, which is registered in advance in map information and detects a recognizable sign set in advance in the environment of the traveling area, or on the traveling path. Get information for obstacle detection and position detection.

  The traveling means 23 includes a battery 23a, and includes driving wheels and auxiliary wheels that are independently driven by the battery 23a on the left and right sides. The battery 23 a supplies power not only to the driving wheels but also to each part of the autonomous mobile device 2 such as the environment recognition unit 22 and the travel control unit 24. The autonomous mobile device 2 is steered by the difference in the number of rotations of the left and right drive wheels. The rotational speed of the drive wheel can be used as information for the position information acquisition unit 45 to acquire its own position, as will be described later.

  The traveling control means 24 controls the traveling means 23 so as to autonomously move to the destination while generating a route to the destination and avoiding an obstacle when the destination is commanded. The travel control means 24 has a function of generating a travel route, grasping the state of the autonomous mobile device 2, and controlling equipment such as the travel means 23 based on information from the environment recognition means 22. Information obtained from the environment recognizing means 22, a storage unit 41 that stores information, an operation area map information 42, a route generation unit 43 that generates a movement route based on the map information 42 when a destination is specified, and The obstacle detection unit 44 that detects an obstacle based on the position, the position information acquisition unit 45 that recognizes the position of the autonomous mobile device 2 on the map and acquires the position information of its current location, and the traveling unit 23 are controlled. And a travel control unit 46.

  The memory | storage part 41 has memorize | stored the above-mentioned map information 42, and has memorize | stored the parameter required for autonomous movement, The information regarding the upper limit of the stay time of the autonomous mobile apparatus 2 used in order to determine a deadlock state Parameters such as (stop time T1 described later) are stored.

  The map information 42 includes sign information for self-position recognition in the operation area, node information used by the route generation unit 43 described below to generate a movement route, and the like. A node is a number of target points that are defined and distributed in the operating area of the autonomous mobile device 2, for example, grid points that are distributed and arranged in a wide traveling area, with the bend of the movable path being a node. Is a node. The coordinate values of each node, information such as whether the nodes are one-way or two-way, and the mutual connection relationship between the nodes are set and defined as node information. Further, the map information 42 includes arrangement information of standby points serving as destinations for the autonomous mobile device 2 in the deadlock state to temporarily move to eliminate the deadlock.

  The route generation unit 43 uses the node information included in the map information 42 to generate a movement route from the current location to the destination. Here, an outline of the generation of the movement route using the node information by the route generation unit 43 will be described (for details of the generation of the movement route shown below, refer to, for example, JP-A-2005-050105).

  The above-described node information is defined by setting cost (evaluation values such as distance, time, energy, etc.) information necessary for moving between nodes in addition to the mutual connection relationship between the nodes. When generating a travel route from the current location to the destination, the route generation unit 43 uses the concept of travel cost as a basic concept of travel route optimization and travel efficiency. The movement cost can be estimated by time, energy, etc. required to move between two points. As the most general cost, the linear distance between two points or the sum of the linear distances can be used. However, depending on the function of the autonomous mobile device 2, the concept of travel cost differs.

  Since the autonomous mobile device 2 proceeds while reviewing the movement route in order to avoid obstacles and minimize the movement cost, the movement route may be regenerated at each time point during movement. The travel route generated by the route generation unit 43 is generated so as to follow a predetermined node in the map information 42 stored in the storage unit 41, that is, via the node.

  The obstacle detection unit 44 obtains the position of the obstacle with respect to the autonomous mobile device 2 from information obtained by, for example, a laser radar, an ultrasonic sensor, an imaging device, or the like provided in the environment recognition unit 22. The information is referred to by the travel control unit 46 and the route generation unit 43 to perform collision avoidance and obstacle avoidance, and travel speed change and travel route change are performed.

  The position information acquisition unit 45, for example, incorporates a gyro or attaches an encoder to the wheel of the traveling means 23, and integrates the movement distance and rotation angle from the output acceleration information and wheel rotation speed information. Thus, the self position and the posture (the position and the traveling direction of the autonomous mobile device 2) are obtained, and the self position on the map of the map information 42 is acquired. Further, the self-position can be corrected by confirming the sign detected by the environment recognition means 22 on the map. The information on the position coordinate and the posture acquired in this way is transmitted as position information to the central controller 3 via the communication units 21 and 31.

  As shown in FIG. 3, the central control device 3 includes a communication unit 31 that performs wireless communication with the communication unit 21 of the autonomous mobile device 2 described above, and an operation instruction unit 32 that controls the autonomous mobile device 2. It is equipped with.

  The communication unit 31 receives position information from a plurality of autonomous mobile devices 2 and transmits an instruction including the destination to each autonomous mobile device 2.

  The operation instructing unit 32 includes a storage unit 51 that stores various parameters, an operation area map information 52, and a deadlock determination unit 53 and a deadlock cancellation unit 54 that detect and eliminate the deadlock state of the autonomous mobile device 2, respectively. And.

  The map information 52 is stored in the storage unit 51 and is map information equivalent to the map information 42 provided in the autonomous mobile device 2. By providing the map information 42 and 52 that are equivalent to each other, the operation of the autonomous mobile device group control system 1 without wrinkles is realized. The map information 52 is not limited to the same map information as the map information 42 of the autonomous mobile device 2, but may be map information that includes at least destination and standby point information and can determine the standby point of the autonomous mobile device 2. That's fine.

  The deadlock determination unit 53 detects a state in which a plurality of autonomous mobile devices 2 stay within a predetermined distance from each other for a predetermined time based on the received position information, and these autonomous mobile devices are dead from each other. Judged to be locked.

  The deadlock cancellation unit 54 is configured to move at least one autonomous mobile device 2 out of the autonomous mobile devices 2 that are in a deadlock state when the deadlock determination unit 53 determines that a plurality of autonomous mobile devices 2 are in the deadlock state. An instruction to change the destination of the device 2 is issued. That is, the deadlock canceling unit 54 determines the destination of the autonomous mobile device 2 so as to cancel the deadlock state. The destination change instruction is transmitted from the central control device 3 to the autonomous mobile device 2 via the communication unit 31.

(Communication contents in the system)
In communication between the autonomous mobile device 2 and the central control device 3, as shown in FIG. 4, at least “state, destination, coordinate” information is transmitted from the autonomous mobile device 2 to the central control device 3. Information of at least “destination instruction, stop command” is transmitted to the autonomous mobile device 2.

  The “state” transmitted from the autonomous mobile device 2 is information selected from, for example, waiting, moving, moving speed, and stopped. The “destination” is a destination (such as destination coordinates or name) instructed from the central control apparatus, a retreat destination that is autonomously moving to avoid an obstacle, and the like. The “coordinate” is map information shared by the autonomous mobile device 2 and the central control device 3, that is, information on the current position coordinates and posture (traveling direction, that is, a rotation angle with respect to the coordinate axis) in a common coordinate system. including. These pieces of information can be information classified in more detail. In addition, the communication content can be reduced only by changing the communication content.

  The “destination instruction” transmitted from the central control device 3 is an instruction of a destination as a destination of the immediate movement when the autonomous mobile device 2 receives this instruction. This destination may be a destination where the autonomous mobile device 2 is moving as a target for the original purpose, or a destination (waiting point) that temporarily moves to eliminate a deadlock state. The “stop command” includes a stop command for avoiding the occurrence of deadlock in the autonomous mobile device 2, a stop command for temporarily stopping to cancel the deadlock state, and a stop command for responding to an emergency situation.

(Deadlock state and its resolution example)
In the deadlock state, as shown in FIG. 5 (a), in the traveling region A defined by the wall W or the like, the two autonomous mobile devices 2 that are moving are facing each other within a certain distance within a certain time. Can be defined as not moving. Therefore, the deadlock determination unit 53 is also moving with respect to each autonomous mobile device 2 within the distance D1 (that is, continuing the moving state) and is stopped for a certain period of time. To detect a deadlock condition. Here, the autonomous mobile device 2 being stopped for a certain time means that the travel distance of the autonomous mobile device 2 is within a certain distance within a certain time.

  In response to the above-described deadlock state, the deadlock canceling unit 54 cancels the deadlock state by moving one of the autonomous mobile devices 2 to the standby point P as shown in FIG.

  According to the method for eliminating the deadlock state as described above, a state where the vehicle has stopped and stayed within a predetermined distance for a longer period of time is detected as a deadlock state, so that the detection of the deadlock state is simple and easy. Therefore, it is possible to realize early detection and elimination of a deadlock state, and to improve the operating efficiency of the system.

(Deadlock elimination control)
Next, deadlock cancellation control in the autonomous mobile device group control system 1 will be described with reference to the flowchart of FIG. The operation instruction means 32 of the central control device 3 acquires information such as “state, destination, coordinates” of each autonomous mobile device 2 via the communication units 21 and 31 (S1).

  Next, the deadlock determination unit 53 sets the variable i = 1 to the variable i = n−1 for the n autonomous mobile devices 2 identified by the variable i to be controlled in the stop time determination loops LPT1 and LPT2. In turn, it is determined whether or not the stop time (stay time) up to the present is equal to or longer than the predetermined time T1 (S2). If it is not equal to or longer than T1, the loop process is advanced (No in S2). Even when the autonomous mobile device 2 is rotating on the spot or performing forward / backward movement for obstacle avoidance operation, if the movement distance is less than a certain distance, the autonomous mobile device 2 It is assumed that the mobile device 2 is stopped.

  In the above-described step S2, the central control device 3 stores the time and position for the time T1 each time position information is obtained from the autonomous mobile device 2 that is moving (while moving), and the current position Is compared with the position before T1 time, and when the movement distance is equal to or less than the preset distance, it is determined that the vehicle is stopped. As a result of such comparison, if the stop time of the autonomous mobile device 2 is equal to or longer than T1 (Yes in S2), in the next deadlock determination loops LPD1 and LPD2, in order from the variable j = i + 1 to the variable j = n, Perform deadlock determination and resolution processing. That is, if there is no other autonomous mobile device 2 within the distance D1 that has a stop time of T1 or longer (No in S3), the loop process is performed assuming that the deadlock state is not established.

  If there is another autonomous mobile device 2 having a stop time of T1 or more within the distance D1 within the distance D1 (Yes in S3), the deadlock determination unit 53 makes the at least two autonomous mobile devices 2 deadlock with each other. Judge that there is. Then, the deadlock cancellation unit 54 issues a stop instruction to one of the autonomous mobile devices 2 via the communication units 21 and 31, and then, at least, changes to other destinations so that the user can leave the place. To cancel the deadlock state (S4).

  When the stop time determination loops LPT1 and LPT2 are finished, the central control device 3 determines whether or not the system is finished, and if finished, ends the process (Yes in S5), otherwise returns to step S1 and returns to the above-described step. The process is repeated at a predetermined control cycle (No in S5).

  With the above series of controls, one of the autonomous mobile devices 2 that have been obstructing each other's movement is moved to another destination so that it can leave the place, so that the deadlock state can be eliminated. it can. That is, among the autonomous mobile devices 2 that are deadlocked to each other, the destination of at least one autonomous mobile device 2 is changed, and the autonomous mobile device 2 that has changed the destination waits at a predetermined standby point. Since the other autonomous mobile devices 2 can move and the deadlock state is eliminated, and the plurality of autonomous mobile devices 2 are separated from each other, it is possible to continue resuming the movement to the original destination as soon as possible. .

  Three examples of a method for selecting one autonomous mobile device 2 from two autonomous mobile devices 2 in a deadlock state will be described. The first method is a method of assigning a number to each autonomous mobile device 2 and changing the destination of the autonomous mobile device with the smaller number.

  The second method is a method of setting a priority order for the autonomous mobile device 2 and changing a destination of the autonomous mobile device 2 having a low priority order. The priority order can be set based on the urgency and importance of the tasks such as conveyance, cleaning, and guidance of each autonomous mobile device 2. The third method is a method of changing the destination of the autonomous mobile device 2 that is closer to or easier to move to the standby point for canceling the deadlock as the change destination. In this case, the deadlock state can be eliminated more quickly.

  Next, a specific example of the occurrence and elimination of a deadlock state will be described with reference to FIG. FIG. 7 shows that three autonomous mobile devices 2 (which are distinguished from # 1, # 2, and # 3, respectively, by numbers in a frame of the shape indicating the autonomous mobile device 2 in the figure, respectively) are limited by walls W or the like. In the traveling area A, a state in which the autonomous mobile device 2 is densely packed within a range of two to three times the entire length is shown. The autonomous mobile device 2 (# 1) and the autonomous mobile device 2 (# 2) face each other, and the deadlock determination unit 53 determines that both are in the deadlock state according to the flowchart of FIG. 6 described above. It shall be.

  The deadlock elimination unit 54 searches for a destination (standby point) of the destination of the autonomous mobile device 2 (# 1), for example, according to the selection method such as the above-described priority order. It is assumed that the standby point is set in advance in the operation area and stored as map information.

  The deadlock eliminating unit 54 connects the autonomous mobile device 2 (# 1) and the nearest standby point P1 with a line segment, and determines whether or not an obstacle exists on the line segment. Here, the obstacle is another autonomous mobile device 2 or a wall W stored in advance as map information.

  In the case of FIG. 7, another autonomous mobile device 2 (# 3) exists as an obstacle. Whether or not the autonomous mobile device 2 is an obstacle to movement may be determined by whether or not the circle R having a predetermined radius surrounding each autonomous mobile device 2 intersects the line segment. Whether the wall W or the like is an obstacle to the movement may be determined based on whether the line segment and the wall W intersect each other. If these intersect, the autonomous mobile device 2 and the wall W are each determined to be an obstacle.

  The deadlock eliminating unit 54 determines that the autonomous mobile device 2 (# 3) is an obstacle, and performs the operation of determining the presence or absence of an obstacle for the other nearest standby point P2 in the same manner as described above. There is no obstacle between the autonomous mobile device 2 (# 1) and the standby point P2. Therefore, the deadlock canceling unit 54 sets the standby point P2 as a new destination, and issues an instruction to change the destination via the communication units 21 and 31, whereby the autonomous mobile device 2 (# 1) is set. Move to the waiting point P2.

  When the deadlock elimination unit 54 determines that there is no nearest standby point for the autonomous mobile device 2 (# 1) based on the result of the determination of the presence or absence of the obstacle, the other autonomous mobile device 2 (# 2) ), The same processing as described above is performed. As a result, the autonomous mobile device 2 (# 2) can be moved, and the deadlock can be eliminated.

  As described above, in the autonomous mobile device group control system 1, the deadlock canceling unit 54 sets the destination so that there is no obstacle on the route along which the autonomous mobile device 2 that changes the destination moves. The autonomous mobile device 2 can be moved quickly and smoothly without any trouble when the vehicle is directed to a destination serving as a standby point (standby point).

  Next, another specific example of occurrence and elimination of a deadlock state will be described with reference to FIG. The state shown in FIG. 8 is that the three autonomous mobile devices 2 are in a deadlock state as in the state of FIG. 7, but there is no standby point that can be set for the autonomous mobile device 2 (# 2). This is different from the case of 7. Therefore, similarly to the above, the deadlock determination unit 53 determines that the deadlock state is established, and the deadlock cancellation unit 54 determines whether the autonomous mobile device 2 (# 1) and the autonomous mobile device 2 (# 2) The destination of the autonomous mobile device 2 is searched. However, the deadlock canceling unit 54 cannot set the destination for the autonomous mobile device 2 (# 2) because the autonomous mobile device 2 (# 3) interferes with the autonomous mobile device 2 (# 1). , Can not set the corresponding waiting point.

  In such a situation, because of the presence of the third autonomous mobile device 2 (# 3), the destination cannot be set for any of the other two autonomous mobile devices 2 facing each other. Is. Therefore, the deadlock eliminating unit 54 attempts to eliminate the deadlock state by moving the third autonomous mobile device 2 (# 3).

  The cancellation of the deadlock state performed by moving the third autonomous mobile device 2 (# 3) described above is performed by the process shown in the flowchart of FIG. That is, in step S4 in FIG. 6, when the destination change instruction to the autonomous mobile device 2 (# 1) and the autonomous mobile device 2 (# 2) fails, the deadlock determination loops LPD1 and LPD2 The autonomous mobile device 2 (# 3) is determined to be in a deadlock state with the autonomous mobile device 2 (# 1). Therefore, the deadlock canceling unit 54 can instruct the third autonomous mobile device 2 (# 3) to change the destination and cancel the deadlock state.

  As described above, the deadlock determination unit 53 can easily determine and cancel the deadlock state by determining each other's deadlock state for each of the two autonomous mobile devices 2 and simplify the processing. Can be speeded up. Even if three or more autonomous mobile devices 2 are in a deadlock state, the deadlock state can be eliminated as a whole by the processing of every two devices.

  As described above, in the autonomous mobile device group control system 1, when the central control device 3 detects a pair of autonomous mobile devices 2 that are stopped within a certain distance from each other for a certain time, Since the destination is changed to another destination, one autonomous mobile device 2 moves, so that the other autonomous mobile device 2 can also move, and the deadlock state can be eliminated as a whole. Further, according to this method, it is possible to eliminate the deadlock state without giving a command from a conventional person or external environment.

  Note that the deadlock determination unit 53 has not been able to set a movable standby point for any of the pair of autonomous mobile devices 2 determined to be in the deadlock state, and the deadlock state has continued for a predetermined period of time. In this case, the central control device 3 notifies the user who manages the autonomous mobile device group control system 1 of an error.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIGS. The autonomous mobile device group control system 1 according to the second embodiment uses the concept of the next node when setting the destination changed to eliminate the deadlock state. The configurations of the autonomous mobile device 2 and the central control device 3 of this embodiment are the same as those of the first embodiment, and the description of the same parts is omitted. As shown in FIG. 9, the autonomous mobile device 2 transmits information on “next node” to the central control device 3 in addition to at least “state, destination, coordinates”.

  Here, the next node will be described. FIG. 10 shows a destination ne which is a destination instructed from the central control device 3 and a next node nd1. When the autonomous mobile device 2 receives the destination instruction from the central control device 3, the autonomous mobile device 2 refers to the map information stored in advance and connects the nodes in the map information according to a predetermined rule to generate a travel route to the destination ne. To do. When the movement route is generated, the autonomous mobile device 2 moves by sequentially tracing the nodes connected to each other. At this time, the node on which the autonomous mobile device 2 is heading next is referred to as a “next node”. In the case of FIG. 10, the node nd1 closest to the current location is the next node.

(Description of operation)
FIG. 11 shows a flowchart of deadlock elimination control processing in the second embodiment. This flowchart is different from the flowchart shown in FIG. 6 in that the processing in step S4 is changed to the content in step S40, and the other points are the same as those in FIG.

  In step 40, the deadlock elimination unit 54 issues a stop instruction to one of the autonomous mobile devices 2 via the communication units 21 and 31, and thereafter, the destination (waiting point) opposite to the original traveling direction. ) Is selected and a change instruction to the destination is issued to cancel the deadlock state. Here, the opposite side is a direction at least 90 degrees away from the traveling direction.

  A specific example of the above destination selection will be described. FIG. 12 shows a case where the autonomous mobile device 2 uses the node nd1 as the next node and a case where the node nd2 serves as the next node. Here, the traveling direction of the autonomous mobile device 2 is defined as a direction from the autonomous mobile device 2 toward the next node nd1 or the node nd2, as indicated by an arrow in FIG. The central control device 3 acquires the traveling direction of the autonomous mobile device 2 based on the position coordinates of the autonomous mobile device 2 and the position coordinates of the next node.

  Next, a method for selecting a standby point using the concept of the next node, that is, the concept of the traveling direction of the autonomous mobile device 2 will be described. FIG. 13 shows the autonomous mobile device 2 that is moved to eliminate the deadlock state, the next node nd, and two standby points P1 and P2. The standby point P1 is positioned in a direction rotated by an angle θ1 in the right direction from the traveling direction, and the standby point P2 is positioned in a direction rotated by an angle θ2 in the left direction from the traveling direction.

  The deadlock elimination unit 54 of the central control device 3 refers to the map information to search for the nearest standby point, the direction from the autonomous mobile device 2 to each standby point P1, P2, and the progress of the autonomous mobile device 2 The angles θ1 and θ2 formed with the direction are obtained. Next, the deadlock elimination unit 54 searches for an angle that is 90 degrees or more in order from the nearest standby point with respect to the autonomous mobile device 2, and sets the destination that changed the standby point that gives an angle of 90 degrees or more as a communication unit. Through 21 and 31, an instruction to move to the destination is transmitted to the autonomous mobile device 2.

  In the case of FIG. 13, the standby point P1 is the nearest standby point for the autonomous mobile device 2, but θ1 <90 degrees, so that the central control device 3 does not have the standby point P1 in the direction opposite to the traveling direction. This is judged and rejected. Since the standby point P2 satisfies θ2> 90 degrees, the central controller 3 selects the next closest standby point P2 and issues a movement instruction with this standby point P2 as the destination.

  As described above, the deadlock elimination unit 54 sets the destination so that the traveling direction of the autonomous mobile device 2 that changes the destination is opposite to the original traveling direction, that is, backs up. Therefore, it is easy to select a destination as a standby point, and the deadlock state can be resolved more reliably than when moving forward.

(Third embodiment)
A standby point selection method in the autonomous mobile device group control system 1 according to the third embodiment will be described with reference to FIG. The configurations of the autonomous mobile device 2 and the central control device 3 of the present embodiment are the same as those of the first embodiment.

  FIG. 14 shows a deadlock state between the autonomous mobile device 2 (# 1) and the autonomous mobile device 2 (# 2) in the narrow travel area A surrounded by the wall W. Here, it is assumed that there is a traveling area A along the Y-axis direction, and that the autonomous mobile device 2 (# 1) has a lower priority and is moved first. The deadlock determination unit 53 detects this deadlock state, and the deadlock cancellation unit 54 searches for a standby point of one autonomous mobile device 2 (# 1).

  First, the deadlock elimination unit 54 compares the Y coordinate values of the two with reference to the position coordinates of the autonomous mobile device 2 (# 1) and the autonomous mobile device 2 (# 2), and determines the obtained coordinate value. Basically, a standby point P1 having a Y coordinate value larger than the Y coordinate value is set in the autonomous mobile device 2 (# 1) having a large Y coordinate value.

  If the deadlock canceling unit 54 does not set or cannot set a standby point for the autonomous mobile device 2 (# 1), the deadlock canceling unit 54 A standby point P2 having a Y coordinate value smaller than the Y coordinate value is set.

  In the third embodiment, in order to detect the directionality of the autonomous mobile device 2, the magnitude relationship of coordinate values is used instead of the next node in the second embodiment described above. Therefore, in the method of the third embodiment, the standby point can be set by comparing the coordinate values, so that the deadlock state can be resolved by determining the destination of the autonomous mobile device 2 with a smaller amount of calculation.

  The present invention is not limited to the above-described configuration, and various modifications can be made. For example, a normal node for generating a travel route can be used as a standby point, or a specific place is reserved for standby and used in a place other than standby. You can also. The autonomous mobile device 2 can include traveling means 2 that can rotate on the spot and can also include traveling means 2 that can move in all directions. The autonomous mobile device 2 can be configured as a device that autonomously moves in a two-dimensional manner and performs operations and operations such as cleaning, monitoring, assembly, repair, collection, painting, and guidance, in addition to carrying work. .

The block diagram of the autonomous mobile device group control system which concerns on the 1st Embodiment of this invention. The block block diagram of the autonomous mobile apparatus in a control system same as the above. The block block diagram of the central control apparatus in a control system same as the above. Communication explanatory drawing between the autonomous mobile apparatus and central control apparatus in a control system same as the above. (A) is an explanatory top view of the deadlock state which generate | occur | produces in a control system same as the above, (b) is a top view which shows the method of canceling the deadlock state of (a). The flowchart of the deadlock cancellation | release control processing in a control system same as the above. The explanatory top view of the example which cancels the deadlock state which occurs in the control system same as the above. The explanatory top view of other examples which cancel the deadlock state which occurs in a control system same as the above. Communication explanatory drawing between the autonomous mobile apparatus and central control apparatus in the autonomous mobile apparatus group control system which concerns on the 2nd Embodiment of this invention. The top view explaining the next node in a control system same as the above. The flowchart of the deadlock cancellation | release control processing in a control system same as the above. The top view explaining the advancing direction of the autonomous mobile apparatus in a control system same as the above. The top view explaining the selection method of the standby point in a control system same as the above. The top view explaining the selection method of the standby point in the autonomous mobile device group control system which concerns on the 3rd Embodiment of this invention. The top view explaining the intersection and the collision of the path | route of the autonomous mobile apparatus in a prior art example. The top view explaining the possibility of the collision of the autonomous mobile apparatus in a prior art example. The top view explaining the general deadlock state occurrence situation.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Autonomous mobile device group control system 2 Autonomous mobile device 3 Central control device 21 Communication part (autonomous mobile device)
31 Communication unit (for central control unit)
45 position information acquisition unit 53 deadlock determination unit 54 deadlock elimination unit

Claims (4)

Autonomous movement comprising a plurality of autonomous mobile devices that autonomously move to a destination while generating a route to the destination and avoiding an obstacle, and a central controller that directs each of the autonomous mobile devices to the destination In the device group control system,
The autonomous mobile device is
A position information acquisition unit that recognizes its own position and acquires its own position information;
A communication unit that transmits the position information acquired by the position information acquisition unit to the central control device or receives an instruction including a destination from the central control device, and
The central controller is
A communication unit that receives position information from the autonomous mobile device or transmits an instruction including a destination to the autonomous mobile device; and
A dead state in which a plurality of autonomous mobile devices are detected to stay in a predetermined distance from each other for longer than a predetermined time based on the received position information and are determined to be in a deadlock state with respect to each other. A lock determination unit;
An instruction to change the destination of at least one autonomous mobile device among the autonomous mobile devices that are in a deadlock state when a plurality of autonomous mobile devices are determined to be in a deadlock state by the deadlock determination unit. An autonomous mobile device group control system comprising: a deadlock elimination unit that issues   2. The autonomous mobile device group control system according to claim 1, wherein the deadlock determination unit determines each other's deadlock state for two autonomous mobile devices.   3. The autonomous mobile device according to claim 1, wherein the deadlock eliminating unit sets the destination so that there is no obstacle on a route along which the autonomous mobile device that changes the destination moves. Group control system.   The deadlock elimination unit sets the destination so that the traveling direction of the autonomous mobile device that changes the destination is opposite to the original traveling direction. The autonomous mobile device group control system described.

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