Mechanical Engineering, a branch of engineering involved in the design, manufacture, measurement, control, and operation of machinery. Aircraft, railway engines, and motor cars are examples of mechanical engineering in practice. The expertise of mechanical engineers in machine mechanisms, energy, materials, and, increasingly, computer technology is vital to most branches of technology.
Early civilizations used elementary mechanical devices like the wheel, lever, and pulley, drew on wind and water for power, and made basic tools from metals and minerals. In the Middle Ages, more sophisticated mechanisms were produced for new scientific instruments, clocks, and locks. With the Industrial Revolution, machines and tools emerged that used power generated by the steam engine. With the construction of the railways and the transformation of a ship and marine engineering, mechanical engineering became recognized as a separate discipline.
In the 20th century, developments in, for example, air transport, owed much to mechanical engineers, who developed an understanding of the air motion around aircraft as well as new construction materials for aeroplane engines and bodies and enabled the change over from the piston to jet engines. Development of plastics, composite materials, ceramics, and new metal alloys, such as titanium and aluminium, prompted mechanical engineers to incorporate these advanced materials in applications that had previously been manufactured from steel.
From the 1960s onward, computer control of machine tools and the introduction of the flexible manufacturing system brought in automation in the batch production of components. This, together with the later developments of computer-aided design, solid modelling, robotics, machine tool control, and process-planning and control, transformed the traditional role of mechanical engineers in design, manufacture, and control. Computer-aided mass production that was founded in traditional industries where mechanical engineering was important is now used widely, for example, by food manufacturers.
III ROLE OF THE MECHANICAL ENGINEER
Owing to the rapidity of technological progress mechanical engineers have had to keep up with advances in electrical and electronics engineering, computer technology, and materials technology, incorporated into new products, processes, and procedures. They also have to be much more aware of the environmental implications of their work and of customers’ and manufacturers’ demands, and the economic viability of products.
These requirements are reflected in university mechanical engineering courses. Students must achieve competency in the fundamental subjects of mathematics and physics, as well as chemistry, design, engineering practice, mechanics, thermodynamics and fluid mechanics, dynamics and control, and materials science. Manufacturing systems, tribology (friction and lubricants), computer technology, advanced materials, management, and, increasingly, languages, are additional areas of practical study.
As well as in large industries, mechanical engineers may be employed in smaller companies that use computer-based technology, or are manufacturing products based on new technology. Their range of activities has expanded to include work in many rapidly advancing areas, such as medical technology: mechanical engineers may work with surgeons in studies of blood flow and materials for replacement body parts, for example. In agriculture, understanding of dynamics is applied to tractor design and knowledge of materials and computing applied to the handling of vegetable crops by robots. Mechanical engineers are involved in environmental improvements through work on recycling technologies and on cleaner methods of production. They will continue in the future to rely on computer systems and on increasingly complex technologies and materials while maintaining the discipline’s foundations of design, manufacture, measurement, control, and operation.