System and Method for Test Tube and Cap Identification

Abstract

A system for identifying test tube types and properties in a sample handling machine using visual information automatically obtained by an optical imager and then processed using vision processing methods. The system includes an optical imager positioned to capture images containing one or more test tubes in a rack and a microcontroller programmed to extract predetermined regions of interest and interpret the optical information in the image to decipher the dimension of the test tubes, determine the presence or absence of caps on the test tubes, decode any encoded data, and interpret custom symbologies. The system may then determine the nature of the test tubes or other containers presented before the image and provide that information to the sample handling machine to assist with processing of samples.

1 . An apparatus for identifying a test tube, comprising:
 an imager for acquiring an optical image of the tube;   a microcontroller associated with said imager;   a host interface interconnected to said microcontroller; and   wherein said microcontroller is programmed to identify the test tube in at least a portion of the optical image and then output information about the test tube through said host interface.   
     
     
         2 . The apparatus of  claim 1 , wherein said microcontroller is programmed to determine the identity of the test tube from the optical image by extracting a first region of interest from the image, detecting a first set of features of the test tube in the first region of interest, and comparing the first set of detected features against a predetermined standard. 
     
     
         3 . The apparatus of  claim 2 , wherein said microcontroller is further programmed to determine the identity of the test tube by extracting a second region of interest from the optical image, detecting a second set of features of the test tube in the first region of interest, and comparing the second set of detected features against a predetermined standard. 
     
     
         4 . The apparatus of  claim 3 , wherein the microcontroller is programmed to detect the first set of features of by cropping the first region of interest from the optical image, locating a set of points in the first region of interest, and comparing the location of the points against of a predetermined standard. 
     
     
         5 . The apparatus of  claim 4 , wherein the first set of features comprises the presence or absence of a cap on the test tube. 
     
     
         6 . The apparatus of  claim 5 , wherein the first set of features further comprises the length and width of at least a portion of the test tube. 
     
     
         7 . The apparatus of  claim 6 , wherein the second set of features comprise a custom indicia placed on the test tube. 
     
     
         8 . The apparatus of  claim 7 , wherein said microcontroller is programmed to extract a third region of interest from the image and extract barcode information from the third region of interest. 
     
     
         9 . A method detecting the identity of a test tube, comprising:
 acquiring an optical image including the test tube;   identifying a first region of interest in the image;   detecting a first set of features in the first region of interest;   cropping the image to remove areas outside of the first region of interest;   extracting the first set of features from the image;   comparing the first set of features against a predetermined standard   identifying the test tube based on the first set of features;   outputting the identity of the test tube.   
     
     
         10 . The method of  claim 9 , wherein the step of detecting a first set of features in the first region of interest comprises the step of performing edge detection in the first region of interest to locate the test tube. 
     
     
         11 . The method of  claim 10 , wherein the step of extracting the first set of features from the image comprises locating a plurality of points in the image that define the outer geometry of the test tube. 
     
     
         12 . The method of  claim 11 , wherein the first set of features include the presence of absence of a cap on the test tube. 
     
     
         13 . The method of  claim 12 , wherein the first set of features further include the width and length of at least a portion of the test tube. 
     
     
         14 . The method of  claim 9 , further comprising the steps of:
 identifying a second region of interest from the image;   detecting a second set of features in the second region of interest;   cropping the image to remove areas outside of the first and second region of interest;   extracting the second set of features from the image;   comparing the second set of features against a predetermined standard;   identifying the test tube based on the first and second set of features;   outputting the identity of the test tube.   
     
     
         15 . The method of  claim 14 , further comprising the steps of
 identifying a third region of interest from the image;   extracting barcode information from the third region of interest.