Engineering is the practice of systematically applying natural science and mathematics to design and improve systems, devices, or processes that solve problems under constraints. It is typically motivated by satisfying human needs, resulting in creations such as bridges, engines, smartphones, pacemakers, the internet, spacecraft, and washing machines. Engineering involves balancing competing demands such as safety, performance, aesthetics, cost, laws and regulations, and time, while operating within fundamental limits such as the laws of physics.
The traditional disciplines of engineering are civil, mechanical, electrical, and chemical. The academic discipline of engineering encompasses a broad range of more specialized subfields, and each can have a more specific emphasis for applications of mathematics and science. Modern engineering practice follows the engineering design process and spans multiple fields, which include designing and improving infrastructure, machinery, vehicles, electronics, materials, and energy systems.definition of "engineering" from:
As a human endeavor, engineering has existed since ancient times, starting with the six classic simple machines. Examples of large-scale engineering projects from antiquity include impressive structures like the pyramids, elegant temples such as the Parthenon, and water conveyances like hulled watercraft, canals, and the Roman aqueduct. Early machines were powered by humans and animals, then later by wind. Machines of war were invented for siegecraft. In Europe, the scientific and industrial revolutions advanced engineering into a scientific profession and resulted in continuing technological improvements. The steam engine provided much greater power than animals, leading to mechanical propulsion for ships and railways. Further scientific advances resulted in the application of engineering to electrical, chemical, and aerospace requirements, plus the use of new materials for greater efficiencies.
The word engineering is derived from the Latin . Engineers typically follow a code of ethics that favors honesty and integrity, while being dedicated to public safety and welfare. Engineering tasks involve finding optimal solutions to constrained problems, with testing and simulations being used prior to production. When a deployed product fails, forensic engineering is used to determine what went wrong in order to find a fix. Much of this product lifecycle management is now assisted with computer software, from design to testing and manufacturing. At larger scales, this process is normally funded by a company, multiple investors, or the government, so a knowledge of economics and business practices is needed.
Definition The American Engineers' Council for Professional Development (the predecessor of the Accreditation Board for Engineering and Technology aka ABET) has defined "engineering" as:
History
Engineering has existed since ancient times, when humans devised inventions such as the wedge, lever, wheel and pulley, etc.
The term engineering is derived from the word engineer, which itself dates back to the 14th century when an engine'er (literally, one who builds or operates a siege engine) 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). Notable examples of the obsolete usage which have survived to the present day are military engineering corps, e.g., the U.S. Army Corps of Engineers.
The word "engine" itself is of even older origin, ultimately deriving from the Latin (), meaning "innate quality, especially mental power, hence a clever invention."Origin: 1250–1300; ME engin < AF, OF < L ingenium nature, innate quality, esp. mental power, hence a clever invention, equiv. to in- + -genium, equiv. to gen- begetting; Source: Random House Unabridged Dictionary, Random House, Inc. 2006.
Later, as the design of civilian structures, such as bridges and buildings, matured as a technical discipline, the term civil engineering entered the lexicon as a way to distinguish between those specializing in the construction of such non-military projects and those involved in the discipline of military engineering.
Ancient era
The pyramids in ancient Egypt, ziggurats of Mesopotamia, the Acropolis and Parthenon in Greece, the Roman aqueducts, Via Appia and Colosseum, Teotihuacán, and the Brihadeeswarar Temple of Thanjavur, among many others, stand as a testament to the ingenuity and skill of ancient civil and military engineers. Other monuments, no longer standing, such as the Hanging Gardens of Babylon and the Pharos of Alexandria, were important engineering achievements of their time and were considered among the Seven Wonders of the Ancient World.
The six classic simple machines were known in the ancient Near East. The wedge and the inclined plane (ramp) were known since prehistoric times. The wheel, along with the wheel and axle mechanism, was invented in Mesopotamia (modern Iraq) during the 5th millennium BC. The lever mechanism first appeared around 5,000 years ago in the Near East, where it was used in a simple balance scale, and to move large objects in Egyptian technology. The lever was also used in the shadoof water-lifting device, the first crane machine, which appeared in Mesopotamia BC, and then in Egyptian technology . The earliest evidence of pulleys date back to Mesopotamia in the early 2nd millennium BC, and ancient Egypt during the Twelfth Dynasty (1991–1802 BC). The screw, the last of the simple machines to be invented, first appeared in Mesopotamia during the Neo-Assyrian period (911–609) BC. The Egyptian pyramids were built using three of the six simple machines, the inclined plane, the wedge, and the lever, to create structures like the Great Pyramid of Giza.
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. The earliest practical water-powered machines, the water wheel and watermill, first appeared in the Persian Empire, in what are now Iraq and Iran, by the early 4th century BC.
Kush developed the Sakia during the 4th century BC, which relied on animal power instead of human energy. Hafirs were developed as a type of reservoir in Kush to store and contain water as well as boost irrigation. Kushite ancestors built speos during the Bronze Age between 3700 and 3250 BC. Bloomeries and blast furnaces were also created during the 7th centuries BC in Kush. Wooden plank-built seafaring ships were being engineered and built during the Bronze Age, as evidenced by the Uluburun shipwreck, dated from around 1300 BCE.
Ancient Greece developed machines in both civilian and military domains, as evidenced by the writings of Philo of Byzantium and others. The Antikythera mechanism, an early known mechanical analog computer, and the mechanical inventions of Archimedes, are examples of Greek 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 widely used in fields such as robotics and automotive engineering.
Ancient Chinese, Greek, Roman and Hunnic armies employed military machines and inventions such as artillery which was developed by the Greeks around the 4th century BC, Quote: "The 7th century, by contrast, had witnessed rapid innovations, such as the introduction of the hoplite and the trireme, which still were the basic instruments of war in the 5th.' and "But it was the development of artillery that opened an epoch, and this invention did not predate the 4th century. It was first heard of in the context of Sicilian warfare against Carthage in the time of Dionysius I of Syracuse." the trireme, the ballista and the catapult, the trebuchet by Chinese circa 6th-5th century BCE.
Middle Ages The earliest practical wind-powered machines, the windmill and wind pump, first appeared in the Muslim world during the Islamic Golden Age, in what are now Iran, Afghanistan, and Pakistan, by the 9th century AD.. The earliest practical steam-powered machine was a steam jack driven by a steam turbine, described in 1551 by Taqi al-Din Muhammad ibn Ma'ruf in Ottoman Egypt.
The cotton gin was invented in India by the 6th century AD, and the spinning wheel was invented in the Islamic world by the early 11th century, both of which were fundamental to the growth of the cotton industry. The spinning wheel was also a precursor to the spinning jenny, which was a key development during the early Industrial Revolution in the 18th century.
The earliest programmable machines were developed in the Muslim world. A music sequencer, a programmable musical instrument, was the earliest type of programmable machine. The first music sequencer was an automated flute player invented by the Banu Musa brothers, described in their Book of Ingenious Devices, in the 9th century. In 1206, Al-Jazari invented programmable automata/robots. He described four automaton musicians, including drummers operated by a programmable drum machine, where they could be made to play different rhythms and different drum patterns.Professor Noel Sharkey, A 13th Century Programmable Robot (Archive), University of Sheffield.
Before the development of modern engineering, mathematics was used by artisans and craftsmen, such as millwrights, clockmakers, instrument makers and surveyors. Aside from these professions, universities were not believed to have had much practical significance to technology.
A standard reference for the state of mechanical arts during the Renaissance is given in the mining engineering treatise De re metallica (1556), which also contains sections on geology, mining, and chemistry. De re metallica was the standard chemistry reference for the next 180 years.
Industrial revolution
The science of classical mechanics, sometimes called Newtonian mechanics, formed the scientific basis of much of modern engineering. With the rise of engineering as a profession in the 18th 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.
Canal building was an important engineering work during the early phases of the Industrial Revolution.
John Smeaton was the first self-proclaimed civil engineer and is often regarded as the "father" of civil engineering. He was an English civil engineer responsible for the design of bridges, canals, harbors, and lighthouses. He was also a capable mechanical engineer and an eminent physicist. Using a model water wheel, Smeaton conducted experiments for seven years, determining ways to increase efficiency. Smeaton introduced iron axles and gears to water wheels. Smeaton also made mechanical improvements to the Newcomen steam engine. Smeaton designed the third Eddystone Lighthouse (1755–59) where he pioneered the use of 'hydraulic lime' (a form of mortar which will set under water) and developed a technique involving dovetailed blocks of granite in the building of the lighthouse. He is important in the history, rediscovery of, and development of modern cement, because he identified the compositional requirements needed to obtain "hydraulicity" in lime; work which led ultimately to the invention of Portland cement.