One of two key components in the process of part production (regardless of whether it is about additive or subtractive manufacturing process) is producing 3D model of the part. We use techniques of geometric modeling to form regular part. Geometric modeling is as important to CAD as governing equilibrium equations to classical engineering fields as mechanics and thermal fluids. Role of geometric modeling is:
To make intelligent decision on the types of entities necessary to use in a particular model that meets certain geometric requirements such as slopes and/or curvatures.
To interpret of unexpected results.
To provide evaluations of CAD/CAM systems.
To innovative use of the tools in particular applications.
To create of new attributes, or modify the obtained.
To provide models to benefit new engineering applications.
Understanding of terminology.
In the heart of the system is mathematical representation (database). Database is connected with mathematical engine, module that performs all mathematical calculations to forming good representation of 3D model. All necessary inputs can be entered to the system via user interface. Output can be provided via computer display and drawing generation interface and devices. Geometric model must be ready for further analysis such as Finite Element Method (FEM) and manufacturing (Computer Aided Manufacturing - CAM with postprocessors).
To perform this, every geometric modeler must satisfy general requirements, such are:
3D model must have complete part representation including topological and geometrical data. Role of topology is to keep links about the connectivity and associativity of the object entities; it determines the relational information between object entities.
Ability to transfer data directly from CAD to CAE and CAM.
To support various engineering applications, such as mass properties, mechanism analysis, FEM and tool path creation for CNC, and so on.