2. WHAT IS CAD?
• Originally CAD includes any techniques that use computers in the
design process including drafting, stress analysis and motion
analysis.
• CAD program/software is an electronic tool that enables you to
make quick and accurate drawings with the use of a computer.
3. What is benefit of CAD?
• Computer drawings are neat, clean, highly presentable, and can be
modified easily.
• With CAD, parts or components can be modeled, visualized, revised,
and improve on the computer screen before any engineering drawings have
been created.
4. What is benefit of CAD?
• Parts that have been modeled can be assembled in the virtual environment of the
computer.
• The relative motion of moving parts can be animated on the computer.
• The part can be analyzed computationally and redesigned.
• The machine tool path or mold filling flow to fabricate the part can be modeled on
the computer.
• The part model can be downloaded to a rapid prototyping system that can create
a physical model of the part in a few hours with virtually no human intervention.
5. CAPABILITIES OF CAD
Some of the important capabilities of using CAD are;
1. Presentations the drawing can be created in fine drawings with presentation symbols and text styles.
2. Flexibility in editing: CAD provides the flexibility to make quick alterations to drawings.
3. Units and accuracy level CAD program allows you to work with great accuracy. You can also work with different units of measure, such as architectural units, engineering
units, scientific units and surveyor units.
4. Storage and access of drawings: It is quick and convenient to organize CAD drawings. You can have thousands of drawings on a computer’s hard disk and you can open
any one of them within seconds.
5. Sharing CAD drawings.
6. Project reporting: The computer can be used to prepare project reports .
7. Engineering analysis: There is a separate category of programs called CAE that can use CAD drawings for engineering analysis.
8. Computer aided manufacturing (CAM) CAM is a common method of manufacturing used by large corporations. These systems import cad drawings into cam programs to
automate the manufacturing process.
6. What is CAD models?
• A CAD model is a computer representation of an object or part.
• It contains all the design information including geometry, dimensions,
tolerances, materials and manufacturing information.
• CAD models replace the paper blueprints and engineering drawings
• The simplest model used in cad is a 2D model. This model is essentially
the computer graphics equivalent to an orthographic projection
7. • A 3D model is the most general model used in CAD software. This
model is equivalent to an isometric view.
• 2 basic types of 3D models are wire frame and surface models.
• In a 3D wire frame model, only edges of the object are represented.
• A 3D surface model defines the object in terms of surfaces such as
plates (flat) and shells (curved) in addition to edges.
CAD MODELS
8. USE OF SOLID MODELS
• Can be used for stress analysis, heat transfer analysis, fluid flow analysis, and
computer aided manufacturing.
• In the manufacturing process to automatically generate machine tool paths to machine
an object.
• To simulate the removal of material from an initial block of material on the computer
• Can be linked to computer numerical control (cnc) machine to carry out the removal of
material automatically allowing many identical parts to be machined based directly on
the solid models.
• To be used in 3D printing.
9. • Major CAD software products
• Autocad (autodesk)
• Mainly for PC
• Pro engineer (PTC)
• Solidworks
• CATIA
• Unigraphics (UGS)
• I-DEAS (SDRC)
