The Industrial Revolution was a period from to where changes in agriculture, manufacturing, mining, transportation, and technology had a profound effect on the social, economic and cultural conditions of the times. It began in the United Kingdom , then subsequently spread throughout Western Europe , North America , Japan , and eventually the rest of the world.
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Starting in the later part of the 18th century, there began a transition in parts of Great Britain's previously manual labour and draft-animal-based economy towards machine-based manufacturing. It started with the mechanisation of the textile industries, the development of iron-making techniques and the increased use of refined coal. The idea that a machine can be decomposed into simple movable elements led Archimedes to define the lever , pulley and screw as simple machines.
By the time of the Renaissance this list increased to include the wheel and axle , wedge and inclined plane. The modern approach to characterizing machines focusses on the components that allow movement, known as joints. Wedge hand axe : Perhaps the first example of a device designed to manage power is the hand axe , also called biface and Olorgesailie. A hand axe is made by chipping stone, generally flint, to form a bifacial edge, or wedge.
A Brief Illustrated History of Machines and Mechanisms (History of Mechanism and Machine Science)
A wedge is a simple machine that transforms lateral force and movement of the tool into a transverse splitting force and movement of the workpiece. The available power is limited by the effort of the person using the tool, but because power is the product of force and movement, the wedge amplifies the force by reducing the movement. This amplification, or mechanical advantage is the ratio of the input speed to output speed.
The faces of a wedge are modeled as straight lines to form a sliding or prismatic joint. Lever: The lever is another important and simple device for managing power. This is a body that pivots on a fulcrum. Because the velocity of a point farther from the pivot is greater than the velocity of a point near the pivot, forces applied far from the pivot are amplified near the pivot by the associated decrease in speed.
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The fulcrum of a lever is modeled as a hinged or revolute joint. Wheel: The wheel is clearly an important early machine, such as the chariot. A wheel uses the law of the lever to reduce the force needed to overcome friction when pulling a load. To see this notice that the friction associated with pulling a load on the ground is approximately the same as the friction in a simple bearing that supports the load on the axle of a wheel.
However, the wheel forms a lever that magnifies the pulling force so that it overcomes the frictional resistance in the bearing. The classification of simple machines to provide a strategy for the design of new machines was developed by Franz Reuleaux , who collected and studied over elementary machines. Simple machines are elementary examples of kinematic chains or linkages that are used to model mechanical systems ranging from the steam engine to robot manipulators.
The bearings that form the fulcrum of a lever and that allow the wheel and axle and pulleys to rotate are examples of a kinematic pair called a hinged joint. Similarly, the flat surface of an inclined plane and wedge are examples of the kinematic pair called a sliding joint. The screw is usually identified as its own kinematic pair called a helical joint. This realization shows that it is the joints, or the connections that provide movement, that are the primary elements of a machine.
Starting with four types of joints, the rotary joint, sliding joint, cam joint and gear joint, and related connections such as cables and belts, it is possible to understand a machine as an assembly of solid parts that connect these joints called a mechanism. Two levers, or cranks, are combined into a planar four-bar linkage by attaching a link that connects the output of one crank to the input of another.
Additional links can be attached to form a six-bar linkage or in series to form a robot. A mechanical system manages power to accomplish a task that involves forces and movement.
Modern machines are systems consisting of i a power source and actuators that generate forces and movement, ii a system of mechanisms that shape the actuator input to achieve a specific application of output forces and movement, iii a controller with sensors that compare the output to a performance goal and then directs the actuator input, and iv an interface to an operator consisting of levers, switches, and displays. This can be seen in Watt's steam engine see the illustration in which the power is provided by steam expanding to drive the piston. The walking beam, coupler and crank transform the linear movement of the piston into rotation of the output pulley.
Finally, the pulley rotation drives the flyball governor which controls the valve for the steam input to the piston cylinder. The adjective "mechanical" refers to skill in the practical application of an art or science, as well as relating to or caused by movement, physical forces, properties or agents such as is dealt with by mechanics. Power flow through a machine provides a way to understand the performance of devices ranging from levers and gear trains to automobiles and robotic systems.
The German mechanician Franz Reuleaux  wrote, "a machine is a combination of resistant bodies so arranged that by their means the mechanical forces of nature can be compelled to do work accompanied by certain determinate motion. More recently, Uicker et al. Waterwheel: Waterwheels appeared around the world around BC to use flowing water to generate rotary motion, which was applied to milling grain, and powering lumber, machining and textile operations. Modern water turbines use water flowing through a dam to drive an electric generator.
Windmill: Early windmills captured wind power to generate rotary motion for milling operations. Modern wind turbines also drives a generator. This electricity in turn is used to drive motors forming the actuators of mechanical systems. Engine: The word engine derives from "ingenuity" and originally referred to contrivances that may or may not be physical devices. See Merriam-Webster's definition of engine. A steam engine uses heat to boil water contained in a pressure vessel; the expanding steam drives a piston or a turbine.
This principle can be seen in the aeolipile of Hero of Alexandria. This is called an external combustion engine. An automobile engine is called an internal combustion engine because it burns fuel an exothermic chemical reaction inside a cylinder and uses the expanding gases to drive a piston. A jet engine uses a turbine to compress air which is burned with fuel so that it expands through a nozzle to provide thrust to an aircraft , and so is also an "internal combustion engine.
Power plant: The heat from coal and natural gas combustion in a boiler generates steam that drives a steam turbine to rotate an electric generator. A nuclear power plant uses heat from a nuclear reactor to generate steam and electric power. This power is distributed through a network of transmission lines for industrial and individual use. Electric servomotors are the actuators for mechanical systems ranging from robotic systems to modern aircraft.
- A Brief Illustrated History of Machines and Mechanisms by Emilio Bautista Paz.
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Fluid Power: Hydraulic and pneumatic systems use electrically driven pumps to drive water or air respectively into cylinders to power linear movement. The mechanism of a mechanical system is assembled from components called machine elements. These elements provide structure for the system and control its movement.
The structural components are, generally, the frame members, bearings, splines, springs, seals, fasteners and covers. The shape, texture and color of covers provide a styling and operational interface between the mechanical system and its users. The assemblies that control movement are also called " mechanisms. The number of degrees of freedom of a mechanism, or its mobility, depends on the number of links and joints and the types of joints used to construct the mechanism.
The general mobility of a mechanism is the difference between the unconstrained freedom of the links and the number of constraints imposed by the joints. The transmission of rotation between contacting toothed wheels can be traced back to the Antikythera mechanism of Greece and the south-pointing chariot of China.
Illustrations by the renaissance scientist Georgius Agricola show gear trains with cylindrical teeth. The implementation of the involute tooth yielded a standard gear design that provides a constant speed ratio. Some important features of gears and gear trains are:. A cam and follower is formed by the direct contact of two specially shaped links. The driving link is called the cam also see cam shaft and the link that is driven through the direct contact of their surfaces is called the follower.
The shape of the contacting surfaces of the cam and follower determines the movement of the mechanism. A linkage is a collection of links connected by joints. Generally, the links are the structural elements and the joints allow movement. Perhaps the single most useful example is the planar four-bar linkage. However, there are many more special linkages:.
A full understanding of the historical development of Technology also needs the help of experts in technical matters who can appreciate and reassess bygone achievements in the light of their own technical knowledge. More collaboration between science historians and technical experts is needed, as is currently the case in the field of Industrial Archaeology. Thus, this book is also an attempt to set out a technical approach to the historical development of machines and mechanisms, but without too many technical details that will prevent its understanding being purely historical.
At the beginning of each chapter there is a global reference to the period embraced, the most relevant facts, and the most significant treatises in the context of machine history. Following this introduction each chapter contains a series of sections on the types of machines that are representative of the period analysed together with illustrations to accompany the text.
A fairly extensive bibliography enables the reader to make a deeper historical analysis. See All Customer Reviews. Shop Textbooks. Add to Wishlist. Mechanization or mechanisation BE is providing human operators with machinery that assists them with the muscular requirements of work or displaces muscular work. In some fields, mechanization includes the use of hand tools. In modern usage, such as in engineering or economics, mechanization implies machinery more complex than hand tools and would not include simple devices such as an un-geared horse or donkey mill.
Devices that cause speed changes or changes to or from reciprocating to rotary motion, using means such as gears , pulleys or sheaves and belts, shafts , cams and cranks , usually are considered machines. After electrification, when most small machinery was no longer hand powered, mechanization was synonymous with motorized machines.
Automation is the use of control systems and information technologies to reduce the need for human work in the production of goods and services. In the scope of industrialization , automation is a step beyond mechanization. Whereas mechanization provides human operators with machinery to assist them with the muscular requirements of work, automation greatly decreases the need for human sensory and mental requirements as well.
Automation plays an increasingly important role in the world economy and in daily experience.