Recursive object model (ROM)—Modelling of linguistic information in engineering design

Throughout the engineering design process, the design problem and design solutions may be represented by natural language, sketches, technical drawings, and process diagrams. Due to its ambiguity and flexibility, natural language processing has not been well integrated into the tools and methods assisting the design process. This paper proposes a new graphic language, called recursive object model (ROM), to represent natural language used in engineering, which are mainly composed by statements. The ROM uses only five basic symbols to represent object, compound object, constraint relationship, predicate relationship and connection relationship. Those five elements are derived mathematically and are proven sufficient for technical English through enumeration. Three case studies addressing different aspects of design are used to demonstrate the usefulness of the ROM.