Solid Modeling:

Mostly objects we see every day are solids and most of them are geometric objects with interior. Solids may be very simple like a cube or very complicated like a piston engine. Solids should have to be represented by their geometry and other characteristics and properties in order to model those using computers.

Solid modelling is the most powerful of the 3-D modelling technique. This provides the user with complete information about the model. Defining an object with a solid model is the easiest of the available three modelling techniques (curves, surfaces and solids). Solid models can be quickly created without having to define individual locations as with wire-frames, unlike wire-frame and surface models, which just contain geometric data. Solid models contain both geometric and topological information of the object. Some of the potential advantages of solid modelling are:

1. Mass properties such as area, volume, weight, centre of gravity and moment of inertia can be determined quickly.

2. It allows the design engineer to develop and evaluate alternative concepts for parts and assemblies while the design is still a theoretical model. Solid models are non-ambiguous.

3. Cross sections can be cut through the three-dimensional models with colour used to identify and highlight different materials and various other features.

4. It helps in interference checking of moving parts and the action of moving parts in three-dimensions in complex assemblies.

5. It is useful for preparing the technical illustrations used in manuals and other documentation because solid modelling can produce very impressive visual displays of objects, using perspective, colour shading and highlighting to create images of photographic quality.