Movement control method for autonomous mobile robot

Patent metadata

Field	Value
Publication number	US-9904285-B2
Application number	US-201615088293-A
Country	US
Kind code	B2
Filing date	Apr 1, 2016
Priority date	Apr 28, 2015
Publication date	Feb 27, 2018
Grant date	Feb 27, 2018

Abstract

A method including, when having completed a task with respect to a first coverage region, selecting a support-target robot from within a robot group, which is a plurality of robots capable of communicating with the first robot, starting to cause the first robot to move toward a second coverage region assigned to the selected second robot, and, when the first robot become newly possible to communicate with a third robot from among the plurality of robots while moving toward the second coverage region, determining whether to alter the support-target robot to the third robot, when the support-target robot is determined to be altered to third robot, starting to cause the first robot to move toward a third coverage region that is assigned to the third robot.

First claim

What is claimed is:

1. A movement control method in a robot system including a plurality of autonomous mobile robots that execute tasks with respect to coverage regions assigned respectively thereto, a first robot of the plurality of autonomous mobile robots comprising:
a communication interface that communicates with the plurality of robots;
a motor that drives the first robot;
a position sensor that detects a location of the first robot;
a memory that stores robot information regarding at least one of the plurality of robots; and
a processor,
the movement control method performed by the processor of the first robot, comprising:
receiving, via the communication interface, from each robot in a robot group, robot information of each robot in the robot group, the robot group including at least one robot of the plurality of robots that is within a communication range of the first robot, the robot information of each robot in the robot group including a robot identifier that identifies the robot, a location of the robot, an expected task end time of the robot, and a task-incomplete region of the robot;
storing, in the memory, the received robot information of each robot in the robot group;
selecting, when a task is completed with respect to a first coverage region assigned to the first robot of the plurality of robots, a second robot as a support-target robot, from the robot group, based on the location of the first robot detected by the position sensor and the robot information stored in the memory;
driving the motor to move the first robot toward a second coverage region assigned to the selected second robot;
determining, whether a third robot of the plurality of robots comes within the communication range of the first robot while the first robot is moving toward the second coverage region;
when it is determined that a third robot of the plurality of robots comes within the communication range of the first robot while the first robot is moving toward the second coverage region, receiving, via the communication interface, from the third robot, information of the third robot including a robot identifier that identifies the third robot, a location of the third robot, an expected task end time of the third robot, and a task-incomplete region of the third robot;
determining whether or not to switch the support-target robot from the second robot to the third robot based on the location of the first robot detected by the position sensor and the robot information stored in the memory and the received information of the third robot; and
when it is determined to switch the support-target robot from the second robot to the third robot, driving the motor to move the first robot toward a third coverage region assigned to the third robot as the support-target robot.

2. The method according to claim 1 , wherein,
in the determining of whether or not to switch the support-target robot, the processor of the first robot determines to switch the support-target robot from the second robot to the third robot, when the expected task end time, at which the third robot will complete a task with respect to the third coverage region, is later than the expected task end time, at which the second robot will complete a task with respect to the second coverage region, and there will be a remaining task for the third robot at a time point at which the first robot will have moved from the location of the first robot to the location of the third robot.

3. The method according to claim 1 , further comprising:
notifying, when the first robot starts moving toward the second coverage region, the second robot of information indicating that the first robot is moving toward the second robot to provide support for completing the task for the second coverage region; and,
notifying, when the first robot starts moving toward the third coverage region, (i) the third robot of information indicating that support for completing the task for the third coverage region is to be provided, and (ii) the second robot of information indicating that the first robot is not moving toward the second robot to provide support for the second robot.

4. The method according to claim 1 , further comprising:
determining, when an M th robot (M being a natural number of 3 or more) of the plurality of robots comes within the communication range of the first robot while the first robot is moving toward an N th coverage region (N being a natural number of 3 or more) that includes the third coverage region and does not include the first coverage region, whether or not to switch the support-target robot to the M th robot; and
driving the motor of the first robot to move the first robot toward an M th coverage region assigned to the M th robot, when it is determined to switch the support-target robot to the M th robot.

5. The method according to claim 4 , wherein
the memory of the first robot further stores frequency information indicating a frequency limit that is a number of times that the support-target robot can be switched, and,
in the determining as to whether or not to switch the support-target robot to the M th robot, the processor of the first robot determines not to switch the support-target robot to the M th robot when a number of times that the support-target robot has been switched exceeds the frequency limit indicated in the frequency information stored in the memory.

6. The method according to claim 1 , further comprising:
acquiring, using the location of the first robot and the robot information of each robot in the robot group stored in the memory, remaining tasks of each robot for a time point at which the first robot will have moved to the location of each robot in the robot group; and,
in the selecting, the first robot selects the second robot as the support-target robot from the robot group, based on the acquired remaining tasks.

7. The method according to claim 6 , wherein
the memory of the first robot stores the robot information of each robot in the robot group received while executing the task with respect to the first coverage region,
the robot information of each robot in the robot group further includes time information indicating a time at which the robot information has been received by the first robot, and
the method further comprises:
driving the motor to move the first robot within the first coverage region, when at least one item of the robot information of each robot in the robot group stored in the memory, has been received by the first robot outside of a prescribed period that is based on a time point at which the task with respect to the first coverage region has been completed;
receiving once again the robot information from a robot corresponding to the at least one item of the robot information stored in the memory, when the robot corresponding to the at least one item of the robot information comes within the communication range of the first robot while the first robot is moving within the first coverage region; and,
in the acquiring of the remaining tasks, the remaining tasks of each robot in the robot group are acquired based on the robot information that has been received once again.

8. The method according to claim 7 , wherein
the memory has additionally stored reception location information indicating a location of the first robot when the first robot received the robot information of each robot in the robot group received while executing the task with respect to the first coverage region, and
the first robot moves within the first coverage region toward the location indicated by the reception location information corresponding to the at least one item of the robot information.

9. The method according to claim 6 , wherein
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Assignees

• Panasonic Ip Corp America

Inventors

• Kuhara Shunsuke

Classifications

• G05D1/0289

  with means for avoiding collisions between vehicles (vehicle fittings for automatically controlling speed including means for detecting potential obstacles B60K31/0008; avoiding obstacles by action on the steering system B62D; radar, sonar, lidar systems designed for anti-collision purposes G01S13/93, G01S15/93, G01S17/93) · CPC title

• G05D1/0219

  ensuring the processing of the whole working surface · CPC title

• G05D1/0027 Primary

  involving a plurality of vehicles, e.g. fleet or convoy travelling (fleet control of land vehicles from a control room G05D1/0297; traffic control systems for road vehicles G08G1/00; for marine craft G08G3/00; for aircraft G08G5/00) · CPC title

• G05D1/0287

  involving a plurality of land vehicles, e.g. fleet or convoy travelling (traffic control systems for road vehicles G08G1/00, particularly anticollision systems G08G1/16) · CPC title

• G05D2201/0203

  Physics · mapped topic