Computer-Aided Design (CAD) Technologies for Biodevices - Advanced Design and Manufacturing Technologies for Biomedical Devices - page 57

provides different case studies linked to the development of real biodevices by using
different simple CAD operations. Some current limitations and future trends, which
will be discussed in following chapters, are also introduced.

4.1 Introduction to Computer-Aided Design (CAD)

The new technologies have had a profound effect on the professions devoted to
three-dimensional design work. Processes like modeling, performing basic stress
and deformation analyses, and even the production of rapid prototypes can be cur-
rently done by a single designer without any need for a range of specialists (Unver
2006 ; Díaz Lantada et al. 2007 ; Lorenzo Yustos et al. 2009 ). Therefore, an experi-
enced designer can be more effectively in touch with what any design decision
involves, which means the overall product development process is optimized in
terms of schedules and costs and can even be customized (Grote and Antonsson
2009 ), as already explained in the introductory chapters of the handbook.
However, this discipline, commonly known as “industrial design,” focused
towards the development of new products to satisfy customer needs is relatively
modern, and its application in the biomedical fi eld even more. It has its origins in
the philosophy and practice of movements like “Arts and Crafts” and the Bauhaus
(“form follows function”) and spreads rapidly to the United States, using products
that had more exclusive forms while still being practical, as a way of promoting
sales (Gropius 1935 ). The term “industrial” design is used because it is linked to the
development of products that are manufactured through industrial processes and
because it is aimed at promoting a product is effectiveness.

Due to its origins, industrial design began to be taught exclusively in art schools
and design workshops (in the most aesthetic sense of the word), ignoring the major
technical aspects of product development, such as carrying out stress and deforma-
tion studies, selecting materials according to mechanical criteria (not only aesthetic
criteria), optimizing geometries for greater strength, thermal effects, and others
(Pahl and Beitz 1996 ). These more technical analyses have traditionally been omit-
ted or performed by engineers using very powerful but also very specifi c calculation
programs, with which designers limited themselves to design (in line with geomet-
ric and aesthetic criteria) and engineers limited themselves to calculation (in line
with theoretical criteria).
It was not until the last decade that this traditional gap between design and cal-
culation programs gradually began to close. A few years ago, it was diffi cult to
apply the potential of calculation programs (like ANSYS or ABAQUS) to study
parts with complex geometries designed with the help of other purely oriented CAD
resources. Also the design programs that now enable complicated parts to be pro-
duced were lacking in computer-aided engineering (CAE) modules for calculation
tasks. The steps forward in producing universal formats (.igs, .stl…) to facilitate
communication and the exchange of information between designers and engineers,
together with the improvements to different “CAD-CAE-CAM” packages or

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