Optical tracking system and tracking method using the same

Abstract

An optical tracking system and a method using the same capable of detecting an exact spatial position and a direction of a target regardless of the distance from the target to be calculated is disclosed. The optical tracking system and a method using the same according to an embodiment of the present invention has an effect of expanding an available area by detecting an exact spatial position and a direction of a target regardless of the distance from the target to be calculated, as well as, a system downsizing is also achieved by significantly reducing size of the marker unit compared with conventional system.

1 . An optical tracking system comprising:
 at least one marker including a ball lens having a surface, on which at least one pattern portion is formed, and configured to reflect light irradiated from at least one external light source;   at least one camera including:
 a lens configured to receive and focus the light reflected from the at least one marker; and 
 an image sensor configured to form an image of the at least one pattern portion based on the focused light; and 
   a processor configured to calculate a spatial position and a direction of the at least one marker by using the image of the at least one pattern portion.   
     
     
         2 . The optical tracking system of  claim 1 , wherein the processor is configured to:
 calculate the direction of the at least one marker by calculating a rotated angle of the at least one marker by using the image of the at least one pattern portion; and   calculate the spatial position of the at least one marker by using the image of the at least one pattern portion and the rotated angle of the at least one market.   
     
     
         3 . The optical tracking system of  claim 2 , wherein the processor is configured to:
 measure a position and a size change of the at least one pattern portion for each area of the image of the at least one pattern portion; and   calculate the rotated angle of the at least one marker by comparing a reference position and a reference size change of the at least one pattern portion for each area of a reference image of the at least one pattern portion with the position and the size change of the at least one pattern portion for each area of the image of the at least one pattern portion.   
     
     
         4 . The optical tracking system of  claim 2 , wherein the processor is configured to:
 measuring a position and a size of the image of the at least one pattern portion; and   calculating the spatial position of the at least one marker by comparing a reference position and a reference size of a reference image of the at least one pattern portion with the position and the size of the image of the at least one pattern portion.   
     
     
         5 . A tracking method comprising:
 by at least one marker including a ball lens having a surface, on which at least one pattern portion is formed on, reflecting light irradiated from at least one external light source;   by a lens included in at least one camera, receiving and focusing the light reflected from the at least one marker;   by an image sensor included in the at least one camera, forming an image of the at least one pattern portion based on the focused light; and   by a processor, calculating a spatial position and a direction of the at least one marker by using the image of the at least one pattern portion.   
     
     
         6 . The tracking method of  claim 5 , wherein calculating the spatial position and the direction of the at least one marker comprises:
 calculating the direction of the at least one marker by calculating a rotated angle of the at least one marker by using the image of the at least one pattern portion; and   calculating the spatial position of the at least one marker by using the image of the at least one pattern portion and the rotated angle of the at least one market.   
     
     
         7 . The tracking method of  claim 6 , wherein calculating the direction of the at least one marker comprises:
 measuring a position and a size change of the at least one pattern portion for each area of the image of the at least one pattern portion; and   calculating the rotated angle of the at least one marker by comparing a reference position and a reference size change of the at least one pattern portion for each area of a reference image of the at least one pattern portion with the position and the size change of the at least one pattern portion for each area of the image of the at least one pattern portion.   
     
     
         8 . The tracking method of  claim 6 , wherein calculating the spatial position of the at least one marker comprises:
 measuring a position and a size of the image of the at least one pattern portion; and   calculating the spatial position of the at least one marker by comparing a reference position and a reference size of a reference image of the at least one pattern portion with the position and the size of the image of the at least one pattern portion.