A dynamic-rule-based framework of engineering drawing recognition and interpretation system

Abstract

This paper introduces the idea that recognition and interpretation of engineering drawings should be two interwoven phases, with each providing feedback to another, and applies this idea to a dynamic-rule-based method. Recognition rules with attributes are obtained by an automatic object feature extraction procedure, and stored in rule database. During the recognition phase, rules are firstly selected according to two attributes, domain and priority. Then the thresholds of the rules are adjusted automatically to obtain better match results and their priorities are modified dynamically to improve recognition efficiency. Especially, the interpretation phase based on the recognition is also valued in validating and rectifying the recognition result automatically and efficiently. This approach was implemented in a system for recognizing and interpreting architectural structure drawings, and has shown to embody good self-adaptability to various drafting conventions. © Springer-Verlag Berlin Heidelberg 2007.