Engineering
The Watt steam engine,
a major driver in the industrial revolution, underscores the
importance of engineering in modern history. This model is on display at the
main building of the ETSIIM in Madrid ,
Spain
Engineering is the discipline, art and profession of
ac
quiring and applying technical, scientific, and mathematical knowledge to
design and implement materials, structures, machines, devices, systems, and processes that safely realize a desired
objective or invention.
The American Engineers'
Council for Professional Development (ECPD, the predecessor of ABET[1])
has defined engineering as follows:
[T]he creative application
of scientific principles to design or develop structures, machines, apparatus,
or manufacturing processes, or works utilizing them singly or in combination;
or to construct or operate the same with full cognizance of their design; or to
forecast their behavior under specific operating conditions; all as respects an
intended function, economics of operation and safety to life and property.
One who practices
engineering is called an engineer, and those licensed to do so may have more formal
designations such as Professional Engineer, Chartered Engineer, Incorporated Engineer, or European Engineer.
The broad discipline of engineering encompasses a range of more specialized subdisciplines, each with a more specific
emphasis on certain fields of application and particular areas of technology.
History
Offshore
wind turbines
represent a modern multi disciplinary engineering problem.
The concept of
engineering has existed since ancient times as humans devised fundamental
inventions such as the pulley, lever, and wheel. Each of these inventions is
consistent with the modern definition of engineering, exploiting basic
mechanical principles to develop useful tools and objects.
The term engineering
itself has a much more recent etymology, deriving from the word engineer,
which itself dates back to 1325, when an engine’er (literally, one who
operates an engine) originally referred to “a constructor of military
engines. In this context, now obsolete, an “engine” referred to a military
machine, i. e., a mechanical contraption used in war (for example,
a catapult).
The word “engine” itself is of even older origin, ultimately deriving from the Latin ingenium (c.
1250), meaning “innate quality, especially mental power, hence a clever
invention.
Later, as the design of
civilian structures such as bridges and buildings matured as a technical
discipline, the term civil engineering[4]
entered the lexicon as a way to distinguish between those specializing in the
construction of such non-military projects and those involved in the older
discipline of military engineering (the original meaning of
the word “engineering,” now largely obsolete, with notable exceptions that have
survived to the present day such as military engineering corps, e.g., the
U.S. Army Corps of Engineers.
Ancient
era
The Pharos of Alexandria, the pyramids
in Egypt,
the Hanging Gardens of Babylon, the Acropolis and the Parthenon
in Greece,
the Roman aqueducts,
Via Appia
and the Colosseum,
Teotihuacán
and the cities and pyramids of the Mayan, Inca and Aztec Empires, the Great Wall of China, among many others, stand
as a testament to the ingenuity and skill of the ancient civil and military
engineers.
The earliest civil engineer
known by name is Imhotep
As one of the officials of the Pharaoh, Djosèr,
he probably designed and supervised the construction of the Pyramid of Djoser
(the Step Pyramid)
at Saqqara
in Egypt around 2630-2611 BC.
He may also have been responsible for the first known use of columns in architecture[citation needed].
Ancient Greece
developed machines in both the civilian and military domains. The Antikythera mechanism, the first known mechanical
computer)[8][9]
and the mechanical inventions of Archimedes are examples of early mechanical engineering. Some
of Archimedes' inventions as well as the Antikythera mechanism required
sophisticated knowledge of differential gearing or epicyclic gearing,
two key principles in machine theory that helped design the gear trains
of the Industrial revolution, and are still widely used today in diverse fields
such as robotics
and automotive engineering
Chinese, Greek and Roman
armies employed complex military machines and inventions such as artillery
which was developed by the Greeks around the 4th century B.C.,[11]
the trireme,
the ballista
and the catapult.
In the Middle Ages, the Trebuchet was developed.
Renaissance
era
The first electrical engineer is considered to be William Gilbert,
with his 1600 publication of De Magnete, who was the originator of the term "electricity"
The first steam engine
was built in 1698 by mechanical engineer Thomas Savery.[13]
The development of this device gave rise to the industrial revolution in the coming decades,
allowing for the beginnings of mass production.
With the rise of
engineering as a profession in the eighteenth century, the term became more
narrowly applied to fields in which mathematics and science were applied to
these ends. Similarly, in addition to military and civil engineering the fields
then known as the mechanic arts became incorporated into engineering.
Modern
era
Electrical engineering can trace its origins in
the experiments of Alessandro Volta in the 1800s, the experiments
of Michael Faraday, Georg Ohm
and others and the invention of the electric motor
in 1872. The work of James Maxwell and Heinrich Hertz
in the late 19th century gave rise to the field of Electronics.
The later inventions of the vacuum tube and the transistor
further accelerated the development of Electronics to such an extent that
electrical and electronics engineers currently outnumber their colleagues of
any other Engineering specialty
The inventions of Thomas
Savery and the Scottish engineer James Watt
gave rise to modern Mechanical Engineering. The development of
specialized machines and their maintenance tools during the industrial
revolution led to the rapid growth of Mechanical Engineering both in its
birthplace Britain and abroad. Chemical Engineering, like its counterpart
Mechanical Engineering, developed in the nineteenth century during the Industrial Revolution. Industrial scale manufacturing demanded new
materials and new processes and by 1880 the need for large scale production of
chemicals was such that a new industry was created, dedicated to the
development and large scale manufacturing of chemicals in new industrial
plants. The role of the chemical engineer was the design of these chemical
plants and processes.
Aeronautical Engineering
deals with aircraft
design while Aerospace Engineering is a more modern term
that expands the reach envelope of the discipline by including spacecraft
design.[14]
Its origins can be traced back to the aviation pioneers around the turn of the
century from the 19th century to the 20th although the work of Sir George Cayley
has recently been dated as being from the last decade of the 18th century.
Early knowledge of aeronautical engineering was largely empirical with some
concepts and skills imported from other branches of engineering.
Only a decade after the
successful flights by the Wright brothers, the 1920s saw extensive
development of aeronautical engineering through development of World War I
military aircraft. Meanwhile, research to provide fundamental background
science continued by combining theoretical physics with experiments.
The first PhD in engineering (technically, applied
science and engineering) awarded in the United States went to Willard Gibbs
at Yale University in 1863; it was also the second
PhD awarded in science in the U.S.
In 1990, with the rise of computer
technology, the first search engine was built by computer engineer
Alan Emtage.
Main
branches of engineering
Engineering, much like
other science, is a broad discipline which is often broken down into several
sub-disciplines. These disciplines concern themselves with differing areas of
engineering work. Although initially an engineer will be trained in a specific
discipline, throughout an engineer's career the engineer may become
multi-disciplined, having worked in several of the outlined areas. Historically
the main Branches of Engineering are categorized as follows:[14][17]
- Chemical engineering - The
exploitation of chemical principles in order to carry out large scale chemical process, as
well as designing new specialty materials and fuels.
- Civil engineering - The design and
construction of public and private works, such as infrastructure
(roads,
railways,
water supply and treatment etc.), bridges
and buildings.
- Electrical engineering - a very broad
area that may encompass the design and study of various electrical &
electronic systems, such as electrical circuits, generators,
motors,
electromagnetic/electromechanical devices, electronic devices, electronic circuits, optical
fibers, optoelectronic devices, computer
systems, telecommunications.
- Mechanical engineering - The design
of physical or mechanical systems, such as engines, powertrains,
kinematic chains, vacuum technology,
and vibration isolation equipment.
With the rapid advancement
of technology
many new fields are gaining prominence and new branches are developing such as materials engineering, computer engineering, software engineering, mechatronics,
robotics,
nanotechnology,
food process engineering, tribology,
molecular engineering, etc. These new
specialties sometimes combine with the traditional fields and form new branches
such as mechanical engineering and mechatronics and electrical and
computer engineering. A new or emerging area of application will commonly
be defined temporarily as a permutation or subset of existing disciplines;
there is often gray area as to when a given sub-field becomes large and/or
prominent enough to warrant classification as a new "branch." One key
indicator of such emergence is when major universities start establishing
departments and programs in the new field.
For each of these fields
there exists considerable overlap, especially in the areas of the application
of sciences to their disciplines such as physics, chemistry and mathematics.
Methodology
Design
of a turbine
requires collaboration of engineers from many fields
Engineers apply the
sciences of physics and mathematics to find suitable solutions to problems or
to make improvements to the status quo. More than ever, engineers are now
required to have knowledge of relevant sciences for their design projects, as a
result, they keep on learning new material throughout their career.
If multiple options exist,
engineers weigh different design choices on their merits and choose the
solution that best matches the requirements. The crucial and unique task of the
engineer is to identify, understand, and interpret the constraints on a design
in order to produce a successful result. It is usually not enough to build a
technically successful product; it must also meet further requirements.
Constraints may include
available resources, physical, imaginative or technical limitations,
flexibility for future modifications and additions, and other factors, such as
requirements for cost, safety, marketability, productibility, and serviceability. By understanding the
constraints, engineers derive specifications
for the limits within which a viable object or system may be produced and
operated.
Problem
solving
Engineers use their
knowledge of science,
mathematics,
and appropriate experience to find suitable
solutions to a problem. Engineering is considered a branch of applied
mathematics and science. Creating an appropriate mathematical model of a problem allows them to
analyze it (sometimes definitively), and to test potential solutions.
Usually multiple reasonable
solutions exist, so engineers must evaluate the different design choices
on their merits and choose the solution that best meets their requirements. Genrich Altshuller, after gathering statistics
on a large number of patents,
suggested that compromises are at the heart of "low-level" engineering designs, while at a
higher level the best design is one which eliminates the core contradiction
causing the problem.
Engineers typically attempt
to predict how well their designs will perform to their specifications prior to
full-scale production. They use, among other things: prototypes,
scale models,
simulations,
destructive tests, nondestructive tests, and stress tests.
Testing ensures that products will perform as expected.
Engineers as professionals
take seriously their responsibility to produce designs that will perform as
expected and will not cause unintended harm to the public at large. Engineers
typically include a factor of safety in their designs to reduce the
risk of unexpected failure. However, the greater the safety factor, the less
efficient the design may be.
The study of failed
products is known as forensic engineering, and can help the product designer
in evaluating his or her design in the light of real conditions. The discipline
is of greatest value after disasters, such as bridge collapses,
when careful analysis is needed to establish the cause or causes of the
failure.
Computer
use
A
computer simulation of high velocity air flow around the Space Shuttle
during re-entry.
As with all modern
scientific and technological endeavors, computers and software play an
increasingly important role. As well as the typical business application software there are a number of
computer aided applications (Computer-aided
technologies) specifically for engineering. Computers can be used to
generate models of fundamental physical processes, which can be solved using numerical methods.
One of the most widely used
tools in the profession is computer-aided design (CAD) software which
enables engineers to create 3D models, 2D drawings, and schematics of their
designs. CAD together with Digital mockup (DMU) and CAE software such as finite element method analysis or analytic element method allows engineers to
create models of designs that can be analyzed without having to make expensive
and time-consuming physical prototypes.
These allow products and
components to be checked for flaws; assess fit and assembly; study ergonomics;
and to analyze static and dynamic characteristics of systems such as stresses,
temperatures, electromagnetic emissions, electrical currents and voltages,
digital logic levels, fluid flows, and kinematics. Access and distribution of
all this information is generally organized with the use of Product Data Management software.
There are also many tools
to support specific engineering tasks such as Computer-aided manufacture (CAM) software
to generate CNC
machining instructions; Manufacturing Process Management software
for production engineering; EDA for printed circuit board (PCB) and circuit schematics
for electronic engineers; MRO applications for maintenance
management; and AEC
software for civil engineering.
In recent years the use of
computer software to aid the development of goods has collectively come to be
known as Product Lifecycle Management (PLM).
Engineering
in a social context
Engineering is a subject
that ranges from large collaborations to small individual projects. Almost all
engineering projects are beholden to some sort of financing agency: a company,
a set of investors, or a government. The few types of engineering that are
minimally constrained by such issues are pro bono
engineering and open design engineering.
By its very nature
engineering is bound up with society and human behavior. Every product or
construction used by modern society will have been influenced by engineering
design. Engineering design is a very powerful tool to make changes to
environment, society and economies, and its application brings with it a great
responsibility. Many engineering societies have established codes of
practice and codes of ethics to guide members and inform the
public at large.
Engineering projects can be
subject to controversy. Examples from different engineering disciplines include
the development of nuclear weapons, the Three Gorges Dam,
the design and use of Sport utility vehicles and the extraction of oil. In
response, some western engineering companies have enacted serious corporate and social responsibility
policies.
Engineering is a key driver
of human development. Sub-Saharan Africa in
particular has a very small engineering capacity which results in many African
nations being unable to develop crucial infrastructure without outside aid. The
attainment of many of the Millennium Development Goals requires the
achievement of sufficient engineering capacity to develop infrastructure and
sustainable technological development.
All overseas development
and relief NGOs make considerable use of engineers to apply solutions in
disaster and development scenarios. A number of charitable organizations aim to
use engineering directly for the good of mankind:
- Engineers Without Borders
- Engineers Against Poverty
- Registered
Engineers for Disaster Relief
- Engineers for a Sustainable
World
Cultural
presence
Engineering is a well
respected profession. For example, in Canada
Sometimes engineering has
been seen as a somewhat dry, uninteresting field in popular culture,
and has also been thought to be the domain of nerds. For example, the
cartoon character Dilbert
is an engineer. One difficulty in increasing public awareness of the profession
is that average people, in the typical run of ordinary life, do not ever have
any personal dealings with engineers, even though they benefit from their work
every day. By contrast, it is common to visit a doctor at least once a year,
the chartered accountant at tax time, and, occasionally, even a lawyer.
This has not always been
so — most British school children in the 1950s were brought up with
stirring tales of 'the Victorian Engineers', chief amongst whom were the Brunels, the Stephensons,
Telford
and their contemporaries.
In science fiction
engineers are often portrayed as highly knowledgeable and respectable
individuals who understand the overwhelming future technologies often portrayed
in the genre. The Star Trek characters Montgomery Scott,
Geordi La Forge,
Miles O'Brien, B'Elanna Torres,
and Charles Tucker III are famous examples.
Occasionally, engineers may
be recognized by the "Iron Ring"--a stainless steel or iron ring worn on the
little finger of the dominant hand. This tradition began in 1925 in Canada United
States
A Professional Engineer's name may be followed by
the post-nominal letters PE or P.Eng in North America . In much of Europe a professional engineer
is denoted by the letters IR, while in the UK
Licensing
and certification
|
|
This section is
missing citations or needs footnotes. Please help add inline citations to guard against
copyright violations and factual inaccuracies. (April
2007)
|
In most Western countries,
certain engineering tasks, such as the design of bridges, electric power
plants, and chemical plants, must be approved by a licensed Professional Engineer, a Chartered Engineer, or an Incorporated Engineer.
Engineering licensure in
the United States remains largely optional for the vast majority of practicing
engineers not directly working on projects deemed to implicate "public
health and safety" (this typically covers civil engineers and government
contractors). This is known as the "industry exemption." And even for
such public-safety projects, it is often sufficient for only the supervising
engineer to have a license.
Consequently, a relatively
small minority of engineers in the United States
Licensure in most states is
generally attainable through combination of education,
pre-examination (Fundamentals of Engineering Exam), examination (Professional
Engineering Exam), and engineering experience (typically in the area of 5+
years). In the United States
In much of Europe and the Commonwealth professional accreditation is
provided by Engineering Institutions, such as the Institution of Civil Engineers from the UK UK
In the UK US United
States
In Canada Canada
The federal US
Even with strict testing
and licensure, engineering disasters still occur. Therefore, the Professional Engineer, Chartered Engineer, or Incorporated Engineer adheres to a strict code
of ethics.
Each engineering discipline and professional society maintains a code of
ethics, which the members pledge to uphold.
Refer also to the Washington accord
for international accreditation details of professional engineering degrees.
Relationships
with other disciplines
Science
Scientists
study the world as it is; engineers create the world that has never been.
Bioreactors
for producing proteins, NRC Biotechnology Research Institute, Montréal , Canada
There exists an overlap
between the sciences and engineering practice; in engineering, one applies
science. Both areas of endeavor rely on accurate observation of materials
and phenomena. Both use mathematics and classification criteria to analyze and
communicate observations.
Scientists are expected to
interpret their observations and to make expert recommendations for practical
action based on those interpretations]. Scientists may also have to
complete engineering tasks, such as designing experimental apparatus or
building prototypes. Conversely, in the process of developing technology
engineers sometimes find themselves exploring new phenomena, thus becoming, for
the moment, scientists.
In the book What
Engineers Know and How They Know It, Walter Vincenti asserts that
engineering research has a character different from that of scientific
research. First, it often deals with areas in which the basic physics
and/or chemistry
are well understood, but the problems themselves are too complex to solve in an
exact manner.
Examples are the use of
numerical approximations to the Navier-Stokes equations to describe aerodynamic
flow over an aircraft, or the use of Miner's rule
to calculate fatigue damage. Second, engineering research employs many semi-empirical methods
that are foreign to pure scientific research, one example being the method of parameter variation.
As stated by Fung et al. in
the revision to the classic engineering text, Foundations of Solid Mechanics:
"Engineering is quite
different from science. Scientists try to understand nature. Engineers try to
make things that do not exist in nature. Engineers stress invention. To embody
an invention the engineer must put his idea in concrete terms, and design
something that people can use. That something can be a device, a gadget, a
material, a method, a computing program, an innovative experiment, a new
solution to a problem, or an improvement on what is existing. Since a design
has to be concrete, it must have its geometry, dimensions, and characteristic
numbers. Almost all engineers working on new designs find that they do not have
all the needed information. Most often, they are limited by insufficient
scientific knowledge. Thus they study mathematics, physics, chemistry, biology
and mechanics. Often they have to add to the sciences relevant to their profession.
Thus engineering sciences are born."
Medicine
and biology
Leonardo da Vinci,
seen here in a self-portrait, has been described as the epitome of the
artist/engineerHe is also known for his studies on human anatomy
and physiognomy
The study of the human
body, albeit from different directions and for different purposes, is an
important common link between medicine and some engineering disciplines. Medicine
aims to sustain, enhance and even replace functions of the human body,
if necessary, through the use of technology.
Modern medicine can replace
several of the body's functions through the use of artificial organs and can
significantly alter the function of the human body through artificial devices
such as, for example, brain implants and pacemakers. The fields of Bionics
and medical Bionics are dedicated to the study of synthetic implants pertaining
to natural systems.
Conversely, some
engineering disciplines view the human body as a biological machine worth
studying, and are dedicated to emulating many of its functions by replacing biology
with technology. This has led to fields such as artificial intelligence, neural networks,
fuzzy logic,
and robotics.
There are also substantial interdisciplinary interactions between engineering
and medicine.
Both fields provide
solutions to real world problems. This often requires moving forward before
phenomena are completely understood in a more rigorous scientific sense and
therefore experimentation and empirical knowledge is an integral part of both.
Medicine, in part, studies
the function of the human body. The human body, as a biological machine, has
many functions that can be modeled using Engineering methods.
The heart for example
functions much like a pump, the skeleton is like a linked structure with
levers, the brain produces electrical signals etc These similarities
as well as the increasing importance and application of Engineering principles
in Medicine, led to the development of the field of biomedical engineering that uses concepts
developed in both disciplines.
Newly emerging branches of
science, such as Systems biology, are adapting analytical tools
traditionally used for engineering, such as systems modeling and computational
analysis, to the description of biological systems.
Art
There are connections
between engineering and art; they are direct in some fields, for example, architecture,
landscape architecture and industrial design
(even to the extent that these disciplines may sometimes be included in a
University's Faculty of Engineering); and indirect in othe
The Art Institute of Chicago, for instance, held an
exhibition about the art of NASA's
aerospace design. Robert Maillart's bridge design is perceived by
some to have been deliberately artistic. At the University of South Florida, an
engineering professor, through a grant with the National Science Foundation, has developed
a course that connects art and engineering.
Among famous historical
figures Leonardo Da Vinci is a well known Renaissance
artist and engineer, and a prime example of the nexus between art and
engineering
Other
fields
In Political science
the term engineering has been borrowed for the study of the subjects of Social engineering and Political engineering, which deal with forming political and social structures
using engineering methodology coupled with political science
principles.