Applications Of A Flexible Pattern Recognition System In Industrial Inspection

A flexible, reliable pattern recognition system has been developed that operates under the difficult viewing conditions encountered in many industrial applications. The system is flexible because it can be trained and retrained by an unskilled operator to recognize a wide variety of pattern sets. The system is reliable because extensive preprocessing of the scanner signals is included to provide immunity to variations in lighting, surface reflectivity, pattern distortion and pattern registration. The system has a number of unique features. A different subset of the pattern set can be selected for recognition in each position in a row of characters. A varying number of characters per row can be accommodated. The patterns can be read a number of times before making a final decision. The reject level can be set by the operator. Also, the operator may overide recognition with manual input when necessary. Initial results achieved with this system indicate that practical solutions exist for the difficult pattern recognition problems that arise in an industrial environment.