Robot cleaner and method of controlling the same

Abstract

Provided is a robot cleaner that travels along a virtual traveling line connecting a start point to a predetermined target point in a straight line. The robot cleaner includes a body having formed therein a space for accommodating a battery, a water container, and a motor, and a pair of rotation plates that have coupled to lower sides thereof, mopping cloths facing a floor surface, and are rotatably disposed on a bottom surface of the body, in which when a shortest distance between the body and the traveling line is greater than or equal to a predetermined reference distance, rotation speeds of the pair of rotation plates are different from each other.

1 .- 20 . (canceled) 
     
     
         21 . A robot cleaner that travels along a virtual traveling line connecting a start point to a predetermined target point in a straight line, the robot cleaner comprising:
 a body having a space therein to accommodate a battery, a water container, and a motor; and   a pair of rotation plates rotatably disposed on a bottom surface of the body, the pair of rotation plates including a first rotation plate and a second rotation plate,   wherein a lower side of the first rotation plate includes a first mopping cloth configured to face a floor surface,   wherein a lower side of the second rotation plate includes a second mopping cloth configured to face the floor surface, and   wherein the first rotation plate and the second rotation plate are configured to have different rotational speeds, in response to a shortest distance between the body and the virtual traveling line being greater than or equal to a predetermined reference distance.   
     
     
         22 . The robot cleaner of  claim 21 , wherein the rotational speed of one of the first rotation plate and the second rotation plate furthest from the virtual traveling line is faster than the rotational speed of an other of the first rotation plate and the second rotation plate. 
     
     
         23 . The robot cleaner of  claim 22 , wherein the rotational speed of the other of the first rotation plate and the second rotation plate is increased in response to the shortest distance between the body and the virtual traveling line decreasing. 
     
     
         24 . The robot cleaner of  claim 21 , wherein the rotational speed of the first rotation plate is controlled to be faster than the rotational speed of the second rotation plate, in response to a midpoint between an axis of rotation of the first rotation plate and an axis of rotation of the second rotation plate being placed on the virtual traveling line after the first mopping cloth passes through the virtual traveling line. 
     
     
         25 . The robot cleaner of  claim 21 , further comprising:
 a virtual connection line connecting an axis of rotation of the first rotation plate to an axis of rotation of the second rotation plate; and   a virtual traveling direction line that is perpendicular to the virtual connection line, intersects the connection line at a midpoint of the connection line and is parallel to the floor surface,   wherein the virtual traveling direction line includes:
 a forward traveling direction line configured to extend parallel to the floor surface toward a direction in which the battery is to be disposed with respect to the virtual connection line; and 
 a backward traveling direction line configured to extend parallel to the floor surface toward a direction in which the water container is to be disposed with respect to the virtual connection line, and 
   wherein the forward traveling direction line and the virtual traveling line intersect each other when an angle formed by intersection between the backward traveling direction line and the virtual traveling line is greater than or equal to a predetermined reference angle.   
     
     
         26 . The robot cleaner of  claim 25 , wherein the rotational speed of one of the first rotation plate and the second rotation plate furthest from the virtual traveling line is faster than the rotational speed of an other of the first rotation plate and the second rotation plate, when an angle formed by the intersection between the backward traveling direction line and the virtual traveling line is greater than or equal to the predetermined reference angle. 
     
     
         27 . The robot cleaner of  claim 25 , further comprising:
 a virtual movement point located on the virtual traveling line and disposed at a shortest distance to the midpoint of the connection line; and   a virtual target intersection point located on the virtual traveling line and disposed at a predetermined distance from the virtual movement point toward the predetermined target point,   wherein the virtual target intersection point is a point at which the virtual traveling line and the forward traveling direction line intersect each other.   
     
     
         28 . The robot cleaner of  claim 21 , further comprising:
 a virtual connection line connecting an axis of rotation of the first rotation plate to an axis of rotation of the second rotation plate;   a virtual traveling direction line that is perpendicular to the virtual connection line, intersects the connection line at a midpoint of the virtual connection line and is parallel to the floor surface,   a virtual movement point located on the virtual traveling line and disposed at a shortest distance to the midpoint of the virtual connection line; and   a virtual target intersection point located on the virtual traveling line and disposed at a predetermined distance from the virtual movement point toward the predetermined target point,   wherein the rotational speed of the first rotation plate is faster than the rotational speed of the second rotation plate, in response to the first rotation plate being located further from the virtual target intersection point than the second rotation plate.   
     
     
         29 . The robot cleaner of  claim 21 , wherein a relative movement speed of one of the first mopping cloth and the second mopping cloth located furthest from the virtual traveling line is faster than an other of the first mopping cloth and the second mopping cloth. 
     
     
         30 . The robot cleaner of  claim 21 , further comprising:
 a first motor connected to the first rotation plate; and   a second motor connected to the second rotation plate,   wherein an output of one of the first motor and the second motor located furthest from the virtual traveling line is greater than an output of an other of the first motor and the second motor.   
     
     
         31 . A method of controlling a robot cleaner, the robot cleaner including a body and a pair of rotation plates having lower sides coupled to mopping cloths configured to face a floor surface, the robot cleaner traveling by rotation of the pair of rotation plates, the method comprising:
 a straight traveling operation of causing the robot cleaner to travel along a virtual traveling line connecting a start point to a predetermined target point; and   a straight traveling correction operation of rotating the body of the robot cleaner to approach the virtual traveling line when the robot cleaner deviates from the virtual traveling line.   
     
     
         32 . The method of  claim 31 , wherein in the straight traveling operation, the pair of rotation plates are rotated at a same speed. 
     
     
         33 . The method of  claim 31 , wherein in the straight traveling operation, a first rotation plate among the pair of rotation plates rotates in a direction opposite to a second rotation plate among the pair of rotation plates. 
     
     
         34 . The method of  claim 31 , wherein the straight traveling correction operation comprises a first correction operation of rotating a first rotation plate among the pair of rotation plates located furthest from the virtual traveling line faster than a second rotation plate among the pair of rotation plates. 
     
     
         35 . The method of  claim 34 , wherein the straight traveling correction operation further comprises a second correction operation of increasing the rotation speed of the second rotation plate located closest to the virtual traveling line, after the first correction operation. 
     
     
         36 . The method of  claim 35 , wherein in the second correction operation, the rotation speed of the second rotation plate located closest to the virtual traveling line is increased as a shortest distance between the virtual traveling line and the body of the robot cleaner decreases. 
     
     
         37 . The method of  claim 34 , wherein in the first correction operation, a rotation angle of the body of the robot cleaner increases as a shortest distance between the virtual traveling line and the body of the robot cleaner increases. 
     
     
         38 . The method of  claim 31 , wherein the straight traveling correction operation comprises:
 generating, on the virtual traveling line, a virtual movement point disposed at a shortest distance from the robot cleaner;   generating a target intersection point at a predetermined distance from the virtual movement point to the predetermined target point; and   causing the robot to travel toward the target intersection point.   
     
     
         39 . The method of  claim 31 , further comprising a deviation determination operation of determining whether the robot cleaner deviates from the virtual traveling line. 
     
     
         40 . The method of  claim 39 , wherein the deviation determination operation comprises determining that the robot cleaner deviates from the virtual traveling line, when a shortest distance between the virtual traveling line and a front end of the robot cleaner is greater than or equal to a predetermined reference distance.