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66-535: CASC was officially established in July 1999 as part of a Chinese government reform drive, having previously been one part of the former China Aerospace Corporation. Various incarnations of the program date back to 1956. Along with space and defense manufacture, CASC also produces machinery , chemicals , communications equipment, transportation equipment, computers , medical care products and environmental protection equipment. CASC provides commercial launch services to

132-502: A (near-) synonym both by Harris and in later language derives ultimately (via Old French ) from Latin ingenium 'ingenuity, an invention'. The hand axe , made by chipping flint to form a wedge , in the hands of a human transforms force and movement of the tool into a transverse splitting forces and movement of the workpiece. The hand axe is the first example of a wedge , the oldest of the six classic simple machines , from which most machines are based. The second oldest simple machine

198-440: A farmer. This is a clear example of how agricultural automation is being implemented in real-world farming scenarios. Many farmers are upset by their inability to fix the new types of high-tech farm equipment. This is due mostly to companies using intellectual property law to prevent farmers from having the legal right to fix their equipment (or gain access to the information to allow them to do it). In October 2015 an exemption

264-454: A foot apart, blanketing the field with crops. Transplanters automate the task of transplanting seedlings to the field. With the widespread use of plastic mulch , plastic mulch layers, transplanters, and seeders lay down long rows of plastic , and plant through them automatically. After planting, other agricultural machinery such as self-propelled sprayers can be used to apply fertilizer and pesticides . Agriculture sprayer application

330-421: A great leap forward. Instead of harvesting grain by hand with a sharp blade , wheeled machines cut a continuous swath. Instead of threshing the grain by beating it with sticks, threshing machines separated the seeds from the heads and stalks. The first tractors appeared in the late 19th century. Power for agricultural machinery was originally supplied by ox or other domesticated animals . With

396-411: A large drawbar pull. The slow speed of steam-powered machines led farmers to comment that tractors had two speeds: "slow, and damn slow". The internal combustion engine ; first the petrol engine , and later diesel engines ; became the main source of power for the next generation of tractors. These engines also contributed to the development of the self-propelled combine harvester and thresher, or

462-401: A lever is modeled as a hinged or revolute joint . Wheel: The wheel is 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

528-420: A machine is "a device for applying power or changing its direction."McCarthy and Soh describe a machine as a system that "generally consists of a power source and a mechanism for the controlled use of this power." Human and animal effort were the original power sources for early machines. Waterwheel: Waterwheels appeared around the world around 300 BC to use flowing water to generate rotary motion, which

594-470: 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." Notice that forces and motion combine to define power . More recently, Uicker et al. stated that

660-838: 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 ." Mechanisms are generally classified as gears and gear trains , which includes belt drives and chain drives , cam and follower mechanisms, and linkages , though there are other special mechanisms such as clamping linkages, indexing mechanisms , escapements and friction devices such as brakes and clutches . The number of degrees of freedom of

726-500: 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. It is described by the Chebychev–Grübler–Kutzbach criterion . The transmission of rotation between contacting toothed wheels can be traced back to

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792-412: 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. If a is the distance from the pivot to the point where the input force is applied and b is the distance to the point where the output force is applied, then a/b is the mechanical advantage of the lever. The fulcrum of

858-430: 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

924-520: A programmable drum machine , where they could be made to play different rhythms and different drum patterns. During the Renaissance , the dynamics of the Mechanical Powers , as the simple machines were called, began to be studied from the standpoint of how much useful work they could perform, leading eventually to the new concept of mechanical work . In 1586 Flemish engineer Simon Stevin derived

990-445: A specialized growing chamber". It includes the development of Open Phenom , an open source library with open data sets for climate recipes which link the phenotype response of plants (taste, nutrition) to environmental variables, biological, genetic and resource-related necessary for cultivation (input). Plants with the same genetics can naturally vary in color, size, texture, growth rate, yield, flavor, and nutrient density according to

1056-455: 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 in which the power is provided by steam expanding to drive the piston. The walking beam, coupler and crank transform

1122-646: A system of mechanisms that shape the actuator input to achieve a specific application of output forces and movement. They can also include computers and sensors that monitor performance and plan movement, often called mechanical systems . Renaissance natural philosophers identified six simple machines which were the elementary devices that put a load into motion, and calculated the ratio of output force to input force, known today as mechanical advantage . Modern machines are complex systems that consist of structural elements, mechanisms and control components and include interfaces for convenient use. Examples include:

1188-579: A variety of grain crops. The name derives from its combining four separate harvesting operations— reaping , threshing , gathering , and winnowing —into a single process. Among the crops harvested with a combine are wheat , rice , oats , rye , barley , corn ( maize ), sorghum , soybeans , flax ( linseed ), sunflowers and rapeseed . The most common type of seeder is called a planter , and spaces seeds out equally in long rows, which are usually two to three feet apart. Some crops are planted by drills , which put out much more seed in rows less than

1254-403: A wide range of vehicles , such as trains , automobiles , boats and airplanes ; appliances in the home and office, including computers, building air handling and water handling systems ; as well as farm machinery , machine tools and factory automation systems and robots . The English word machine comes through Middle French from Latin machina , which in turn derives from

1320-527: Is SASAC, the company's headquarters are still in Beijing, the business areas remained the same and nothing changed for the staff either. In 2021, China's 14th five year plan included two low Earth orbit satellite constellations named “GW” featuring nearly 13,000 satellites was in development. The "directly subordinated units" of the China Aerospace Science and Technology Corporation are: In 2006

1386-557: Is a method to protect crops from weeds by using herbicides , fungicides , and insecticides. Spraying or planting a cover crop are ways to mix weed growth. Planting crop hay balers can be used to tightly package grass or alfalfa into a storable form for the winter months. Modern irrigation relies on machinery. Engines, pumps and other specialized gear provide water quickly and in high volumes to large areas of land. Similar types of equipment such as agriculture sprayers can be used to deliver fertilizers and pesticides . Besides

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1452-410: 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

1518-423: 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

1584-603: Is distributed through a network of transmission lines for industrial and individual use. Motors: Electric motors use either AC or DC electric current to generate rotational movement. Electric servomotors are the actuators for mechanical systems ranging from robotic systems to modern aircraft . Fluid Power: Hydraulic and pneumatic systems use electrically driven pumps to drive water or air respectively into cylinders to power linear movement . Electrochemical: Chemicals and materials can also be sources of power. They may chemically deplete or need re-charging, as

1650-401: Is made by chipping stone, generally flint, to form a bifacial edge, or wedge . 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

1716-420: Is the case with batteries , or they may produce power without changing their state, which is the case for solar cells and thermoelectric generators . All of these, however, still require their energy to come from elsewhere. With batteries, it is the already existing chemical potential energy inside. In solar cells and thermoelectrics, the energy source is light and heat respectively. The mechanism of

1782-421: Is the planar four-bar linkage . However, there are many more special linkages: A planar mechanism is a mechanical system that is constrained so the trajectories of points in all the bodies of the system lie on planes parallel to a ground plane. The rotational axes of hinged joints that connect the bodies in the system are perpendicular to this ground plane. A spherical mechanism is a mechanical system in which

1848-510: 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

1914-509: The Greek ( Doric μαχανά makhana , Ionic μηχανή mekhane 'contrivance, machine, engine', a derivation from μῆχος mekhos 'means, expedient, remedy' ). The word mechanical (Greek: μηχανικός ) comes from the same Greek roots. A wider meaning of 'fabric, structure' is found in classical Latin, but not in Greek usage. This meaning is found in late medieval French, and is adopted from

1980-781: The People's Liberation Army , which included CASC. In August 2022, CASC's 9th Academy 771 and 772 Research Institutes were added to the United States Department of Commerce 's Entity List . Machinery A machine is a physical system that uses power to apply forces and control movement to perform an action. The term is commonly applied to artificial devices, such as those employing engines or motors, but also to natural biological macromolecules, such as molecular machines . Machines can be driven by animals and people , by natural forces such as wind and water , and by chemical , thermal , or electrical power, and include

2046-565: 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. Three of the simple machines were studied and described by Greek philosopher Archimedes around

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2112-491: 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

2178-422: The soil for planting by loosening the soil and killing weeds or competing plants. The best-known is the plow , the ancient implement that was upgraded in 1838 by John Deere . Plows are now used less frequently in the U.S. than formerly, with offset disks used instead to turn over the soil, and chisels used to gain the depth needed to retain moisture. Combine is a machine designed to efficiently harvest

2244-516: The 3rd century BC: the lever, pulley and screw. Archimedes discovered the principle of mechanical advantage in the lever. Later Greek philosophers defined the classic five simple machines (excluding the inclined plane) and were able to roughly calculate their mechanical advantage. Hero of Alexandria ( c.  10 –75 AD) in his work Mechanics lists five mechanisms that can "set a load in motion"; lever, windlass , pulley, wedge, and screw, and describes their fabrication and uses. However,

2310-547: The French into English in the mid-16th century. In the 17th century, the word machine could also mean a scheme or plot, a meaning now expressed by the derived machination . The modern meaning develops out of specialized application of the term to stage engines used in theater and to military siege engines , both in the late 16th and early 17th centuries. The OED traces the formal, modern meaning to John Harris ' Lexicon Technicum (1704), which has: The word engine used as

2376-606: The Greeks' understanding was limited to statics (the balance of forces) and did not include dynamics (the tradeoff between force and distance) or the concept of work . 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

2442-524: 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

2508-603: The US Department of the Treasury accused Great Wall Industry and its partners of playing a lead role in the development of the Fateh missile system , as Iran had no previous experience with solid-fueled ballistic missiles. In November 2020, U.S. President Donald Trump issued an executive order prohibiting U.S. companies and individuals owning shares in companies that the United States Department of Defense has listed as having links to

2574-579: The United Nations (FAO) defines agricultural automation as the use of machinery and equipment in agricultural operations to improve their diagnosis, decision-making, or performance, reducing the drudgery of agricultural work and improving the timeliness, and potentially the precision, of agricultural operations. The technological evolution in agriculture has been a journey from manual tools to animal traction, then to motorized mechanization, and further to digital equipment. This progression has culminated in

2640-651: The United States, the MIT Media Lab 's Open Agriculture Initiative seeks to foster "the creation of an open-source ecosystem of technologies that enable and promote transparency, networked experimentation, education, and hyper-local production". It develops the Personal Food Computer , an educational project to create a "controlled environment agriculture technology platform that uses robotic systems to control and monitor climate, energy, and plant growth inside of

2706-409: 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 800 elementary machines. He recognized that the classical simple machines can be separated into

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2772-563: The bodies in the system form lines in space that do not intersect and have distinct common normals. A flexure mechanism consists of a series of rigid bodies connected by compliant elements (also known as flexure joints) that is designed to produce a geometrically well-defined motion upon application of a force. Agricultural machinery Agricultural machinery relates to the mechanical structures and devices used in farming or other agriculture . There are many types of such equipment , from hand tools and power tools to tractors and

2838-411: The bodies move in a way that the trajectories of points in the system lie on concentric spheres. The rotational axes of hinged joints that connect the bodies in the system pass through the center of these circle. A spatial mechanism is a mechanical system that has at least one body that moves in a way that its point trajectories are general space curves. The rotational axes of hinged joints that connect

2904-445: The combine harvester (also shortened to 'combine'). Instead of cutting the grain stalks and transporting them to a stationary threshing machine , these combines cut, threshed, and separated the grain while moving continuously throughout the field. Tractors do the majority of work on a modern farm . They are used to push/pull implements —machines that till the ground, plant seeds, and perform other tasks. Tillage implements prepare

2970-547: The combine of today still cuts, threshes, and separates grain in the same way it has always been done. However, technology is changing the way that humans operate the machines, as computer monitoring systems, GPS locators and self-steer programs allow the most advanced tractors and implements to be more precise and less wasteful in the use of fuel, seed, or fertilizer. In the foreseeable future, there may be mass production of driverless tractors , which use GPS maps and electronic sensors. The Food and Agriculture Organization of

3036-571: The double acting steam engine practical. The Boulton and Watt steam engine and later designs powered steam locomotives , steam ships , and factories . The Industrial Revolution was a period from 1750 to 1850 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

3102-430: The farm implements that they tow or operate. Machinery is used in both organic and nonorganic farming. Especially since the advent of mechanised agriculture , agricultural machinery is an indispensable part of how the world is fed. Agricultural machinery can be regarded as part of wider agricultural automation technologies, which includes the more advanced digital equipment and agricultural robotics . While robots have

3168-593: The international market. By the end of 2013, the corporation has registered capital of CN¥294.02 billion and employs 170,000 people. In December 2017, the CASC was restructured from a state-owned enterprise (全民所有制企业) to a state-owned enterprise with limited liability (国有独资公司) with the approval of the State-owned Assets Supervision and Administration Commission of the State Council (SASAC). The sole shareholder

3234-514: The invention of steam power came the portable engine , and later the traction engine , a multipurpose, mobile energy source that was the ground-crawling cousin to the steam locomotive . Agricultural steam engines took over the heavy pulling work of oxen , and were also equipped with a pulley that could power stationary machines via the use of a long belt . The steam-powered machines were low-powered by today's standards but because of their size and their low gear ratios , they could provide

3300-417: The lever, pulley and wheel and axle that are formed by a body rotating about a hinge, and the inclined plane, wedge and screw that are similarly a block sliding on a flat surface. 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

3366-529: 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 . Similarly Merriam-Webster Dictionary defines "mechanical" as relating to machinery or tools. Power flow through

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3432-751: The mechanical advantage of the inclined plane, and it was included with the other simple machines. The complete dynamic theory of simple machines was worked out by Italian scientist Galileo Galilei in 1600 in Le Meccaniche ("On Mechanics"). He was the first to understand that simple machines do not create energy , they merely transform it. The classic rules of sliding friction in machines were discovered by Leonardo da Vinci (1452–1519), but remained unpublished in his notebooks. They were rediscovered by Guillaume Amontons (1699) and were further developed by Charles-Augustin de Coulomb (1785). James Watt patented his parallel motion linkage in 1782, which made

3498-408: The movement. This amplification, or mechanical advantage is the ratio of the input speed to output speed. For a wedge this is given by 1/tanα, where α is the tip angle. 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

3564-446: The other hand, can be transformed into automated vehicles that can sow fields independently. < ref name= ":1"/> A 2023 report by the United States Department of Agriculture (USDA) revealed that over 50% of corn, cotton, rice, sorghum, soybeans, and winter wheat in the United States is planted using automated guidance systems. These systems, which utilize technology to autonomously steer farm equipment, only require supervision from

3630-419: 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

3696-501: The potential to automate the three key steps involved in any agricultural operation (diagnosis, decision-making and performing), conventional motorized machinery is used principally to automate only the performing step where diagnosis and decision-making are conducted by humans based on observations and experience. With the coming of the Industrial Revolution and the development of more complicated machines, farming methods took

3762-403: 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

3828-467: The rest of the world. 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

3894-425: The tractor, other vehicles have been adapted for use in farming, including trucks , airplanes , and helicopters , such as for transporting crops and making equipment mobile, to aerial spraying and livestock herd management. The basic technology of agricultural machines has changed little in the last century. Though modern harvesters and planters may do a better job or be slightly tweaked from their predecessors,

3960-502: The use of robotics with artificial intelligence (AI). Motorized mechanization, for instance, automates operations like ploughing, seeding, fertilizing, milking, feeding, and irrigating, thereby significantly reducing manual labor. With the advent of digital automation technologies, it has become possible to automate diagnosis and decision-making. For instance, autonomous crop robots can harvest and seed crops, and drones can collect information to help automate input applications. Tractors, on

4026-399: 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

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4092-675: Was a steam jack driven by a steam turbine , described in 1551 by Taqi ad-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 . The earliest programmable machines were developed in

4158-667: Was added to the DMCA to allow inspection and modification of the software in cars and other vehicles including agricultural machinery. The Open Source Agriculture movement counts different initiatives and organizations such as Farm Labs which is a network in Europe, l'Atelier Paysan which is a cooperative to teach farmers in France how to build and repair their tools, and Ekylibre which is an open-source company to provide farmers in France with open source software ( SaaS ) to manage farming operations. In

4224-613: 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. A steam engine uses heat to boil water contained in

4290-451: Was the inclined plane (ramp), which has been used since prehistoric times to move heavy objects. The other four simple machines were invented in the ancient Near East . 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

4356-485: Was used in a simple balance scale , and to move large objects in ancient Egyptian technology . The lever was also used in the shadoof water-lifting device, the first crane machine, which appeared in Mesopotamia c.  3000 BC , and then in ancient Egyptian technology c.  2000 BC . The earliest evidence of pulleys date back to Mesopotamia in the early 2nd millennium BC, and ancient Egypt during

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