Patent ID: 11883960
Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
Field: Control (Instruments)
Classification: CPC B  G | IPC B  G

Claim 4:
5. A system for controlling a mobile robot, the system comprising a processor configured to execute a method comprising:
transmitting a position distance calculation command to an adjacent robot, wherein the position distance calculation command comprises a relative position from a position of a predetermined robot (hereinafter referred to as a robot “i_root”) and the number of times of transmission and transfer of the position distance calculation command that are respectively set at predetermined initial values,
wherein a predetermined initial position and a predetermined goal position are set for each of robot units, a common position represents a common part of the initial position and the goal position, a set of common positions is formed by at least one partial common position set that is not adjacent to each other, and connectivity of a robot structure indicating a mass robot structure formed by each of the robot units being adjacent to other robot units;

upon receipt of the position distance calculation command:
incrementing the number of times of transmission and transfer included in the position distance calculation command;
updating the relative position included in the position distance calculation command according to a direction in which the position distance calculation command is received; and
transferring a position distance calculation command including the incremented number of times of transmission and transfer and the updated relative position to an adjacent robot other than the robot that transmits the position distance calculation command only once;

when the position distance calculation command is received first, transmitting a reply position distance calculation command including the incremented number of times of transmission and transfer and the updated relative position to the robot that transmits the position distance calculation command;
storing a direction of the robot that transmits the position distance calculation command as an a_to_root direction when the position distance calculation command is received first;
upon receipt of the reply position distance calculation command, transferring the received reply position distance calculation command in the a_to_root direction;
in a case of the robot being i_root, and upon receipt of reply position distance calculation commands transmitted by all robots:
selecting a partial common position set as a set Up based on a position of each of the robots according to relative positions included in the reply position distance calculation commands;
selecting a head position Head, wherein the head position Head is adjacent to a position among positions in a set of goal positions, outside the set of the common positions, and among positions in the set Up, wherein the set of goal positions represents goal positions of units of the robot; and
transmitting a head robot unit determination command including information on the relative position and the set Up, to a predetermined robot in a head robot unit that is a robot unit located in the head position Head;

in a case of being the predetermined robot in the head robot unit, and upon receipt of the head robot unit determination command, determining robot units H0, H1, . . . , Hnt−1 included in a path from the head position Head to a tail position Tail with a position of a tail robot unit that is a robot unit located in a position that does not belong to the set Up and located in the initial position, and is a robot unit that can maintain connectivity of the robot structure even when the robot unit is moved, as the tail position Tail;
in a case of being a predetermined robot in a robot unit Hi, where i=0, nt-2, moving the robot unit Hi to a destination position D, or a position in which a robot unit Hi−1 is located before movement by the first movement unit while extending a robot unit Hi+1 with a position that is a position adjacent to the head position Head, and belongs to the set of the goal positions but does not belong to the set of the common positions, as the destination position D;
in a case of being a predetermined robot in a robot unit Hnt−2, moving a robot unit Hnt−1 to a position where the robot unit Hnt−2 is located before movement;
a next head robot unit selection command transmission step of a next head robot unit selection command transmission unit, in a case of being a predetermined robot in the robot unit Hnt−2, transmitting a next head robot unit selection command to a predetermined robot in the head robot unit; and
in a case of being a predetermined robot in the head robot unit, and upon receipt of a next head robot unit determination command, when there is a robot unit that is in contact with the set Up and is not located in the set Up but located in the goal position after the destination position D is added to the set Up:
updating the set Up by adding a position of the robot unit, and a position of a robot unit in a connected state via only the goal position from the robot unit to the set Up;
updating the relative position;
selecting a position that is a position adjacent to a position that belongs to the set of the goal positions but does not belong to the set of the common position, and belongs to the set Up, as a head position Head, based on a position of each of the robots based on the relative position; and
transmitting a head robot unit determination command including information on the relative position and the set Up to a predetermined robot in a head robot unit that is a robot unit located in the head position Head;

repeating a set of the determining, the moving the robot Hi, the moving the robot unit nt-1, the moving the robot unit Hnt−2, the transmitting a next head robot unit selection command, the updating the set Up, the updating the relative position, the selecting the position, and the transmitting the head robot unit determination command until there is no position including no robot unit in the goal position.