Modeling of drawings and 3D shapes

A product model in 3D is a model of a physical object that includes a specification of its shape. When a 3D model is a part of a bigger assembly, such as a building, a transport system, a ship or a process plant, then the model also includes its position and orientation in a 3D space. A 3D model forms just a fraction of all the information that is typically stored about a product and the processes in which it is involved. Those other aspects include for example non-shape properties, such as materials of construction, strengths, temperatures and pressures and also relations, such as assembly relations, connection relations with other products and involvements in processes and activities. This means that 3D shape models  should be integrated in a complete set of information and knowledge about a facility. The modelled collection of all facts about a facility is called a Facility Information Model (FIM) or more specialised a Building Information Model (BIM), etc.

Data integration issues

3D product models and 2D drawings are typically created by using software packages of various suppliers. The resulting models are typically stored in the proprietary formats of those packages. For example, in DWG, DXF, CMG, DGN or RVT format. Each of such formats has its own limitations on the type of data that can be stored. Data that is stored in one format can only be converted to another formet when a single or bi-directional converter is created and when the receiving format is suitable for storing all kinds of data that is to be converted.

Non-3D related information about a facility is typically stored in other proprietary system with their own proprietary formats. For example, properties of products (1D data) may be stored in the format of ERP databases or PLM databases, whereas 2D information is usually stored in proprietary 'drawing formats'. The drawing files are typically stored as such in EDMS systems, whereas the content of the drawings is not integrated with other data in databases. The structure of the data as well as the definitions of the concepts are different in each system and in each file format. Therefore, exchange of data between systems and integration of data of different sources raises all sorts of data conversion issues.

The Gellish solution

The Gellish Modelling Method offers a solution to these data integration issues by providing a standard data structure (in Gellish Databases) as well as a standard electronic dictionary of concepts (the Gellish Dictionary/Taxonomy) that include graphical symbols and parameterized 3D shape correlations. They are all integrated in the definition of the Gellish English language and the method to apply the language to create Facility Information Models (FIMs, BIMs, etc.). Gellish is based on various ISO standards, such as ISO 10303 and ISO 15926 that include business data as well as graphical information. For example, the basic geometric concepts to describe shapes are compliant with the ISO STEP standard for geometric objects: ISO 10303-42.

Conventionally data about an object, such as the wall of a building and its construction, is stored in one or more application specific database structures. But in Gellish all data can be stored in one open standard semantic data structure. This means for example that business process oriented systems can be extended in a relative easy way with 3D shape aspects, by specifying dimensions and referring to the standard shapes that are defined in the Gellish dictionary and by positioning the shapes in the coordinate system of the assembly. 

The full article describes how to create, store and exchange any data about a facility, being 1D, 2D and 3D, in one consistent, standardised, integrated and system independent way, using the Gellish Modelling Method.