Operation method of a robot for leading a follower

An operation method of a robot for leading a follower from a start location to a destination within an open space, the robot including a main body, a front laser scanner that is disposed at a front side of the main body for scanning the front of the main body, a rear laser scanner that is disposed at a rear side of the main body for scanning the rear of the main body, a storage unit that stores a map of the open space, a motion control unit disposed at the main body for driving the main body to move within the open space, and a processing unit communicating with the front laser scanner, the rear laser scanner and the motion control unit, the method comprising steps of:

• scanning, by the rear laser scanner, the rear of the main body within a plurality of rear angular ranges to obtain a plurality of rear-scanning data sets that correspond to the plurality of rear angular ranges, respectively;
• A) calculating, by the processing unit, a distance between the follower and the main body based on the plurality of rear-scanning data sets currently obtained by the rear laser scanner;
• B) determining, by the processing unit, whether the distance between the follower and the main body is greater than a threshold;
• C) when it is determined that the distance between the follower and the main body is not greater than the threshold,
• controlling, by the processing unit, the front laser scanner to scan the front of the main body within a plurality of front angular ranges, so as to obtain a plurality of front-scanning data sets that correspond to the plurality of front angular ranges, respectively,
• determining, by the processing unit, a pre-movement location of the main body in the open space and an orientation of the main body based on the map and the plurality of front-scanning data sets currently obtained by the front laser scanner, and
• determining, by the processing unit, a linear speed and an angular speed for the main body based on at least the pre-movement location and the orientation of the main body, the destination and the map;
• D) generating, by the processing unit, a movement command according to the linear speed and the angular speed and transmitting, by the processing unit, the movement command to the motion control unit;
• E) driving, by the motion control unit, the main body to move according to the movement command;
• F) determining, by the processing unit, a current position of the main body in the open space based on the map and the plurality of front-scanning data sets currently obtained by the front laser scanner, and whether the main body has arrived at the destination according to the current position;
• and
• G) repeating steps A) to F) when it is determined that the main body has not arrived at the destination;
• wherein each of the plurality of front-scanning data sets includes the corresponding one of the front angular ranges and a front distance that is measured along a middle angle within the corresponding one of the front angular ranges, the method further comprising, after step C), steps of;
• H) determining, by the processing unit, whether there is at least one obstacle in front of the robot within a minimum safety distance from the robot by determining whether at least one of the front distances respectively of the plurality of front-scanning data sets is shorter than the minimum safety distance;
• I) when it is determined that there is at least one obstacle in front of the robot within the minimum safety distance from the robot, obtaining, by the processing unit, at least one obstacle location vector relative respectively to the at least one obstacle within the minimum safety distance from the robot and a smallest one of the front distances based on the plurality of front-scanning data sets;
• J) calculating, by the processing unit, an obstacle composite vector based on the at least one obstacle location vector and the minimum safety distance;
• and
• K) calculating, by the processing unit, a dodging angular speed based on the orientation of the main body, the obstacle composite vector, the smallest one of the front distances and the linear speed;
• wherein in step D), the movement command is generated further according to the dodging angular speed.

An operation method of a robot for leading a follower from a start location to a destination within an open space, the robot including a main body, a front laser scanner that is disposed at a front side of the main body for scanning the front of the main body, a rear laser scanner that is disposed at a rear side of the main body for scanning the rear of the main body, a storage unit that stores a map of the open space, a motion control unit disposed at the main body for driving the main body to move within the open space, and a processing unit communicating with the front laser scanner, the rear laser scanner and the motion control unit, the method comprising steps of:

• scanning, by the rear laser scanner, the rear of the main body within a plurality of rear angular ranges to obtain a plurality of rear-scanning data sets that correspond to the plurality of rear angular ranges, respectively;
• A) calculating, by the processing unit, a distance between the follower and the main body based on the plurality of rear-scanning data sets currently obtained by the rear laser scanner;
• B) determining, by the processing unit, whether the distance between the follower and the main body is greater than a threshold;
• C) when it is determined that the distance between the follower and the main body is not greater than the threshold,
• controlling, by the processing unit, the front laser scanner to scan the front of the main body within a plurality of front angular ranges, so as to obtain a plurality of front-scanning data sets that correspond to the plurality of front angular ranges, respectively,
• determining, by the processing unit, a pre-movement location of the main body in the open space and an orientation of the main body based on the map and the plurality of front-scanning data sets currently obtained by the front laser scanner, and
• determining, by the processing unit, a linear speed and an angular speed for the main body based on at least the pre-movement location and the orientation of the main body, the destination and the map;
• D) generating, by the processing unit, a movement command according to the linear speed and the angular speed and transmitting, by the processing unit, the movement command to the motion control unit;
• E) driving, by the motion control unit, the main body to move according to the movement command;
• F) determining, by the processing unit, a current position of the main body in the open space based on the map and the plurality of front-scanning data sets currently obtained by the front laser scanner, and whether the main body has arrived at the destination according to the current position;
• and
• G) repeating steps A) to F) when it is determined that the main body has not arrived at the destination;
• wherein the method is further implemented using a server that communicates with the robot and that stores a plurality of user information entries associated respectively with a plurality of users and a plurality of station information entries associated respectively with a plurality of stations in the open space, each of the plurality of user information entries including a progress report indicating whether the user has visited each of the stations, a current location of a current station where the user is currently staying in the open space, and an arrival time when the user arrived at the current station, each of the plurality of station information entries including a station location of the station in the open space and an expected staying duration, during which a user is expected to stay at the station, the method further comprising, prior to step A), steps of:
• L) determining, by the server, whether a candidate user information entry is included in the plurality of user information entries according to the progress reports respectively of the plurality of user information entries, the progress report in the candidate user information entry being associated with a to-be-guided user and indicating at least one station that is yet to be visited by the to-be-guided user;
• O) selecting, by the server, a target station from the at least one station based on the candidate user information entry;
• P) setting, by the server, the station information entry that is associated with the target station as a target station information entry;
• Q) transmitting, by the server, the current location in the candidate user information entry and the station location in the target station information entry to the robot;
• and
• R) performing, by the robot, steps A) to F) in response to receipt of the current location and the station location, using the to-be-guided user associated with the task user information entry as the follower, the current location as the start location and the station location as the destination.