Development of an Automatic Recognition System for Plant Diagrams

In electric generat ion plants , facility administration is going to be computerized for s e c u r e and efficient maintenance, a n d i t is needed t o input many a l ready existing plant diagrams (so called piping & ins t rument diagrams) into computer systems. Then i t i s required to recognize plant diagrams, whose drawing quality is s o tough f o r recognition, t h a t t h e drawn elements, namely, symbols, lines and charac te rs , of ten have contac t s with each other . Thus we developed a n automatic recognition system for plant diagrams, which enabled t o input s u c h diagrams a t recognition rate over 80 %. And toge ther with a n effic ient verification process , t h e total time t o input a diagram is reduced to be u n d e r 30 %, compared t o conventional CAD-system input .