Robot cleaner using edge detection and method of controlling the same

Abstract

A robot cleaner and a method of controlling the same are disclosed. The robot cleaner cleans a given cleaning area simultaneously while moving in the cleaning area. The method includes detecting whether an obstacle exists in a traveling path of the robot cleaner, determining whether the detected obstacle is an edge when the obstacle is detected, cleaning a predetermined area centering around the edge when the detected obstacle is determined to be the edge, and determining whether the cleaning area is completely cleaned on the basis of information of the detected edge while cleaning the predetermined area.

1 . A method of controlling a robot cleaner which cleans a given cleaning area simultaneously while moving in the cleaning area, the method comprising:
 detecting whether an obstacle exists in a traveling path of the robot cleaner;   determining whether the obstacle is an edge when the obstacle is detected;   cleaning a predetermined area centering around the edge when the detected obstacle is determined to be the edge.   
   
   
       2 . The method according to  claim 1 , further comprising:
 determining whether the obstacle is a wall, before determining whether the detected obstacle is the edge.   
   
   
       3 . The method according to  claim 2 , wherein the determining whether the obstacle is the wall includes:
 detecting whether the obstacle is in the traveling path of the robot cleaner;   moving the robot cleaner to go straight in parallel to the obstacle by a first predetermined distance when the obstacle is detected to be in the traveling path of the robot cleaner;   determining whether the obstacle is detected while the robot cleaner goes straight in parallel to the obstacle by the first predetermined distance or more; and   determining that the detected obstacle is the wall when the obstacle is detected while the robot cleaner goes straight in parallel to the obstacle by the first predetermined distance or more.   
   
   
       4 . The method according to  claim 3 , wherein the determining whether the obstacle is the edge includes:
 moving the robot cleaner to go straight in parallel to the wall by a second predetermined distance when the detected obstacle is determined to be the wall;   determining whether the obstacle is detected while the robot cleaner goes straight in parallel to the obstacle by the second predetermined distance or more; and   determining that the detected obstacle is the edge when the obstacle is detected while the robot cleaner goes straight in parallel to the obstacle by the second predetermined distance or more.   
   
   
       5 . The method according to  claim 1 , wherein the predetermined area is a square area formed by the edge and a reference point located in a diagonal direction from the edge. 
   
   
       6 . The method according to  claim 5 , wherein the cleaning of the predetermined area centering around the edge includes:
 moving the robot cleaner to go straight in parallel to the wall by a set distance at coordinates of the edge, rotating the robot cleaner by 90° and moving the robot cleaner to go straight again by the set distance when the detected obstacle is determined to be the edge;   establishing a square area in which a reference point and coordinates of the edge are used as both end points of a diagonal line when the robot cleaner is moved straight by the set distance, rotated by 90°, moved straight again by the set distance and reaches the reference point acting as an arrival point; and   cleaning a cleaning area for each established area.   
   
   
       7 . The method according to  claim 1 , wherein the edge information is indicative of a sum 
     
       
         
           
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     of angles of the robot cleaner which rotates at the edge simultaneously while cleaning the cleaning area. 
   
   
       8 . The method according to  claim 7 , wherein the determining whether the cleaning area is completely cleaned includes:
 calculating the sum   
     
       
         
           
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     of angles of the robot cleaner rotating at the edge; and
 determining whether a predetermined cleaning-completion condition of the cleaning area is satisfied on the basis of both the sum 
 
     
       
         
           
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     of the angles and a number of determined edges. 
   
   
       9 . The method according to  claim 8 , wherein the cleaning-completion condition indicates whether the sum 
     
       
         
           
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     of angles of the robot cleaner rotating at the edge satisfies the following equation: 
     
       
         
           
             
               
                 180 
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                 × 
                 
                   ( 
                   
                     
                       n 
                       c 
                     
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                       n 
                       m 
                     
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                     2 
                   
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               - 
               Δ 
             
             ≤ 
             
               
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                 j 
               
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                 Q 
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             ≤ 
             
               
                 180 
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                       c 
                     
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                       n 
                       m 
                     
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               + 
               Δ 
             
           
         
       
       where, n c  is indicative of the number of edges, n m  is indicative of a number of similar edges, Q j   o  is indicative of an interior angle of a polygon, and Δ is indicative of an error value capable of reducing an error rate when the cleaning-completion condition is determined to be satisfied. 
     
   
   
       10 . A robot cleaner which cleans a given cleaning area simultaneously while moving in the cleaning area, the robot cleaner comprising:
 an obstacle detector detecting whether an obstacle exists in a traveling path of the robot cleaner; and   a controller determining whether the detected obstacle is an edge when the obstacle is detected, cleaning a predetermined area centering around the edge if the detected obstacle is determined to be the edge, and determining whether the cleaning area is cleaned on the basis of information of the edge.   
   
   
       11 . The robot cleaner according to  claim 10 , wherein the controller determines whether the obstacle is a wall before determining whether the detected obstacle is the edge. 
   
   
       12 . The robot cleaner according to  claim 11 , wherein the controller moves the robot cleaner to go straight in parallel to the obstacle by a first predetermined distance when the obstacle is detected in the traveling path of the robot cleaner, determines whether the obstacle is detected while the robot cleaner goes straight in parallel to the obstacle by first predetermined distance or more, and determines that the detected obstacle is the wall when the obstacle is detected while the robot cleaner goes straight in parallel to the obstacle by the first predetermined distance or more. 
   
   
       13 . The robot cleaner according to  claim 12 , wherein the controller moves the robot cleaner to go straight in parallel to the wall by a second predetermined distance when the detected obstacle is determined to be the wall, determines whether the obstacle is detected while the robot cleaner goes straight in parallel to the obstacle by the second predetermined distance or more, and determines that the detected obstacle is the edge when the obstacle is detected while the robot cleaner goes straight in parallel to the obstacle by the second predetermined distance or more. 
   
   
       14 . The robot cleaner according to  claim 10 , wherein the predetermined area is a square area which is formed by the edge and a reference point located in a diagonal direction from the edge. 
   
   
       15 . The robot cleaner according to  claim 1 , further comprising determining whether the cleaning area is cleaned on the basis of information of the determined edge while cleaning the predetermined area. 
   
   
       16 . A method of controlling a robot cleaner, comprising:
 determining coordinates of a detected edge of a wall;   moving the robot cleaner indirectly to a reference point located in a diagonal direction from the edge;   determining a cleaning area using coordinates of the detected edge and the reference point; and   cleaning the determined cleaning area.   
   
   
       17 . A method of controlling a robot, comprising:
 detecting an obstacle in a path of the robot cleaner;   determining whether the detected obstacle is a wall; and   performing a cleaning operation specific to the detected obstacle, on the basis of information obtained as a result of the determination as to whether the detected obstacle is a wall.   
   
   
       18 . The method of  claim 17 , wherein the determining whether the detected obstacle is the wall includes:
 moving the robot cleaner to go straight in parallel to the obstacle; and   determining that the obstacle is the wall when the obstacle is detected while the robot cleaner moves straight in parallel to the obstacle by a predetermined distance or more.   
   
   
       19 . A robot cleaner, comprising:
 an obstacle detector detecting an obstacle in a path of the robot cleaner, the obstacle detected being an edge of a wall; and   a controller determining coordinates of a detected edge of a wall; moving the robot cleaner to a diagonal point from the detected edge with respect to the wall; determining a cleaning area using coordinates of the detected edge and the diagonal point; and controlling the robot cleaner to clean the determined cleaning area.