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Introduction to Mechanical Engineering Design 9
as Aries, AutoCAD, CadKey, I-Deas, Unigraphics, Solid Works, and ProEngineer, to
name a few.
The term computer-aided engineering (CAE) generally applies to all computer-
related engineering applications. With this definition, CAD can be considered as a sub-
set of CAE. Some computer software packages perform specific engineering analysis
and/or simulation tasks that assist the designer, but they are not considered a tool for the
creation of the design that CAD is. Such software fits into two categories: engineering-
based and non-engineering-specific. Some examples of engineering-based software for
mechanical engineering applications—software that might also be integrated within a
CAD system—include finite-element analysis (FEA) programs for analysis of stress
and deflection (see Chap. 19), vibration, and heat transfer (e.g., Algor, ANSYS, and
MSC/NASTRAN); computational fluid dynamics (CFD) programs for fluid-flow analy-
sis and simulation (e.g., CFD++, FIDAP, and Fluent); and programs for simulation of
dynamic force and motion in mechanisms (e.g., ADAMS, DADS, and Working Model).
Examples of non-engineering-specific computer-aided applications include software
for word processing, spreadsheet software (e.g., Excel, Lotus, and Quattro-Pro), and
3
mathematical solvers (e.g., Maple, MathCad, MATLAB, Mathematica, and TKsolver).
Your instructor is the best source of information about programs that may be available
to you and can recommend those that are useful for specific tasks. One caution, however:
Computer software is no substitute for the human thought process. You are the driver here;
the computer is the vehicle to assist you on your journey to a solution. Numbers generated
by a computer can be far from the truth if you entered incorrect input, if you misinterpreted
the application or the output of the program, if the program contained bugs, etc. It is your
responsibility to assure the validity of the results, so be careful to check the application and
results carefully, perform benchmark testing by submitting problems with known solu-
tions, and monitor the software company and user-group newsletters.
Acquiring Technical Information
We currently live in what is referred to as the information age, where information is gen-
erated at an astounding pace. It is difficult, but extremely important, to keep abreast of past
and current developments in one’s field of study and occupation. The reference in Footnote
2 provides an excellent description of the informational resources available and is highly
recommended reading for the serious design engineer. Some sources of information are:
• Libraries (community, university, and private). Engineering dictionaries and encyclo-
pedias, textbooks, monographs, handbooks, indexing and abstract services, journals,
translations, technical reports, patents, and business sources/brochures/catalogs.
• Government sources. Departments of Defense, Commerce, Energy, and Transportation;
NASA; Government Printing Office; U.S. Patent and Trademark Office; National
Technical Information Service; and National Institute for Standards and Technology.
• Professional societies. American Society of Mechanical Engineers, Society of
Manufacturing Engineers, Society of Automotive Engineers, American Society for
Testing and Materials, and American Welding Society.
• Commercial vendors. Catalogs, technical literature, test data, samples, and cost
information.
• Internet. The computer network gateway to websites associated with most of the
categories listed above. 4

3 MATLAB is a registered trademark of The MathWorks, Inc.
4 Some helpful Web resources, to name a few, include www.globalspec.com, www.engnetglobal.com,
www.efunda.com, www.thomasnet.com, and www.uspto.gov.