![Roue primitive](https://upload.wikimedia.org/wikipedia/commons/3/32/Roue_primitive.png)
A wheel is a circular component that is intended to rotate on an
axle
An axle or axletree is a central shaft for a rotating wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to the vehicle, with the wheels rotating around the axle. In the former case, bearing ...
bearing. The wheel is one of the key components of the
wheel and axle
The wheel and axle is a simple machine consisting of a wheel attached to a smaller axle so that these two parts rotate together in which a force is transferred from one to the other. The wheel and axle can be viewed as a version of the lever, wi ...
which is one of the
six simple machines. Wheels, in conjunction with axles, allow heavy objects to be moved easily facilitating movement or transportation while supporting a load, or performing labor in machines. Wheels are also used for other purposes, such as a
ship's wheel
A ship's wheel or boat's wheel is a device used aboard a water vessel to steer that vessel and control its course. Together with the rest of the steering mechanism, it forms part of the helm. It is connected to a mechanical, electric servo, or h ...
,
steering wheel
A steering wheel (also called a driving wheel (UK), a hand wheel, or simply wheel) is a type of steering control in vehicles.
Steering wheels are used in most modern land vehicles, including all mass-production automobiles, buses, light and ...
,
potter's wheel
In pottery, a potter's wheel is a machine used in the shaping (known as throwing) of clay into round ceramic ware. The wheel may also be used during the process of trimming excess clay from leather-hard dried ware that is stiff but malleable, a ...
, and
flywheel
A flywheel is a mechanical device which uses the conservation of angular momentum to store rotational energy; a form of kinetic energy proportional to the product of its moment of inertia and the square of its rotational speed. In particular, ass ...
.
Common examples are found in
transport
Transport (in British English), or transportation (in American English), is the intentional movement of humans, animals, and goods from one location to another. Modes of transport include air, land (rail and road), water, cable, pipeline, an ...
applications. A wheel reduces
friction
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. There are several types of friction:
*Dry friction is a force that opposes the relative lateral motion of t ...
by facilitating motion by
rolling
Rolling is a type of motion that combines rotation (commonly, of an axially symmetric object) and translation of that object with respect to a surface (either one or the other moves), such that, if ideal conditions exist, the two are in contact ...
together with the use of
axles
An axle or axletree is a central shaft for a rotation, rotating wheel and axle, wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to the vehicle, with the wheels rotating around the axle. In ...
. In order for wheels to rotate, a
moment needs to be applied to the wheel about its axis, either by way of gravity or by the application of another external force or
torque
In physics and mechanics, torque is the rotational equivalent of linear force. It is also referred to as the moment of force (also abbreviated to moment). It represents the capability of a force to produce change in the rotational motion of th ...
. Using the wheel,
Sumerians
Sumer () is the earliest known civilization in the historical region of southern Mesopotamia (south-central Iraq), emerging during the Chalcolithic and early Bronze Ages between the sixth and fifth millennium BC. It is one of the cradles of c ...
invented a device that spins clay as a potter shapes it into the desired object.
Terminology
The English word ''
wheel
A wheel is a circular component that is intended to rotate on an axle Bearing (mechanical), bearing. The wheel is one of the key components of the wheel and axle which is one of the Simple machine, six simple machines. Wheels, in conjunction wi ...
'' comes from the
Old English
Old English (, ), or Anglo-Saxon, is the earliest recorded form of the English language, spoken in England and southern and eastern Scotland in the early Middle Ages. It was brought to Great Britain by Anglo-Saxon settlement of Britain, Anglo ...
word , from
Proto-Germanic
Proto-Germanic (abbreviated PGmc; also called Common Germanic) is the reconstructed proto-language of the Germanic branch of the Indo-European languages.
Proto-Germanic eventually developed from pre-Proto-Germanic into three Germanic branc ...
, from
Proto-Indo-European
Proto-Indo-European (PIE) is the reconstructed common ancestor of the Indo-European language family. Its proposed features have been derived by linguistic reconstruction from documented Indo-European languages. No direct record of Proto-Indo-E ...
, an extended form of the root "to revolve, move around".
Cognates within Indo-European include
Icelandic "wheel, tyre",
Greek
Greek may refer to:
Greece
Anything of, from, or related to Greece, a country in Southern Europe:
*Greeks, an ethnic group.
*Greek language, a branch of the Indo-European language family.
**Proto-Greek language, the assumed last common ancestor ...
, and
Sanskrit
Sanskrit (; attributively , ; nominally , , ) is a classical language belonging to the Indo-Aryan branch of the Indo-European languages. It arose in South Asia after its predecessor languages had diffused there from the northwest in the late ...
, the last two both meaning "circle" or "wheel".
History
The place and time of the invention of the wheel remains unclear, because the oldest hints do not guarantee the existence of real wheeled transport, or are dated with too much scatter.
Mesopotamia
Mesopotamia ''Mesopotamíā''; ar, بِلَاد ٱلرَّافِدَيْن or ; syc, ܐܪܡ ܢܗܪ̈ܝܢ, or , ) is a historical region of Western Asia situated within the Tigris–Euphrates river system, in the northern part of the F ...
n civilization is credited with the invention of the wheel. However, unlike other breakthrough inventions, the wheel cannot be attributed to a single nor several inventors. Evidence of early usage of wheeled carts has been found across the
Middle East
The Middle East ( ar, الشرق الأوسط, ISO 233: ) is a geopolitical region commonly encompassing Arabian Peninsula, Arabia (including the Arabian Peninsula and Bahrain), Anatolia, Asia Minor (Asian part of Turkey except Hatay Pro ...
, in
Europe
Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...
,
Eastern Europe
Eastern Europe is a subregion of the Europe, European continent. As a largely ambiguous term, it has a wide range of geopolitical, geographical, ethnic, cultural, and socio-economic connotations. The vast majority of the region is covered by Russ ...
,
India
India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...
and
China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...
. It is not known whether Chinese, Indians and Europeans invented the wheel independently or not.
The invention of the solid wooden disk wheel falls into the late
Neolithic
The Neolithic period, or New Stone Age, is an Old World archaeological period and the final division of the Stone Age. It saw the Neolithic Revolution, a wide-ranging set of developments that appear to have arisen independently in several parts ...
, and may be seen in conjunction with other technological advances that gave rise to the early
Bronze Age
The Bronze Age is a historic period, lasting approximately from 3300 BC to 1200 BC, characterized by the use of bronze, the presence of writing in some areas, and other early features of urban civilization. The Bronze Age is the second pri ...
. This implies the passage of several wheelless millennia even after the
invention of agriculture
The Neolithic Revolution, or the (First) Agricultural Revolution, was the wide-scale transition of many human cultures during the Neolithic period from a lifestyle of hunter-gatherer, hunting and gathering to one of agriculture and sedentism, ...
and of
pottery
Pottery is the process and the products of forming vessels and other objects with clay and other ceramic materials, which are fired at high temperatures to give them a hard and durable form. Major types include earthenware, stoneware and por ...
, during the
Aceramic Neolithic
Pre-Pottery Neolithic A (PPNA) denotes the first stage of the Pre-Pottery Neolithic, in early Levantine and Anatolian Neolithic culture, dating to years ago, that is, 10,000–8,800 BCE. Archaeological remains are located in the Levantine and Up ...
.
* 4500–3300 BCE (
Copper Age
The Copper Age, also called the Chalcolithic (; from grc-gre, χαλκός ''khalkós'', "copper" and ''líthos'', "stone") or (A)eneolithic (from Latin '' aeneus'' "of copper"), is an archaeological period characterized by regular ...
): invention of the
potter's wheel
In pottery, a potter's wheel is a machine used in the shaping (known as throwing) of clay into round ceramic ware. The wheel may also be used during the process of trimming excess clay from leather-hard dried ware that is stiff but malleable, a ...
; earliest solid wooden wheels (disks with a hole for the axle); earliest wheeled vehicles;
domestication of the horse
A number of hypotheses exist on many of the key issues regarding the domestication of the horse. Although horses appeared in Paleolithic cave art as early as 30,000 BCE, these were wild horses and were probably hunted for meat.
How and when hors ...
* 3300–2200 BCE (
Early Bronze Age
The Bronze Age is a historic period, lasting approximately from 3300 BC to 1200 BC, characterized by the use of bronze, the presence of writing in some areas, and other early features of urban civilization. The Bronze Age is the second prin ...
)
* 2200–1550 BCE (
Middle Bronze Age
The Bronze Age is a historic period, lasting approximately from 3300 BC to 1200 BC, characterized by the use of bronze, the presence of writing in some areas, and other early features of urban civilization. The Bronze Age is the second pri ...
): invention of the
spoke
A spoke is one of some number of rods radiating from the center of a wheel (the hub where the axle connects), connecting the hub with the round traction surface.
The term originally referred to portions of a log that had been riven (split l ...
d wheel and the
chariot
A chariot is a type of cart driven by a charioteer, usually using horses to provide rapid motive power. The oldest known chariots have been found in burials of the Sintashta culture in modern-day Chelyabinsk Oblast, Russia, dated to c. 2000&nbs ...
The
Halaf
Tell Halaf ( ar, تل حلف) is an archaeological site in the Al Hasakah governorate of northeastern Syria, a few kilometers from the city of Ra's al-'Ayn near the Turkish border. The site, which dates to the 6th millennium BCE, was the firs ...
culture of 6500–5100 BCE is sometimes credited with the earliest depiction of a wheeled vehicle, but this is doubtful as there is no evidence of Halafians using either wheeled vehicles or even pottery wheels. Precursors of pottery wheels, known as "tournettes" or "slow wheels", were known in the
Middle East
The Middle East ( ar, الشرق الأوسط, ISO 233: ) is a geopolitical region commonly encompassing Arabian Peninsula, Arabia (including the Arabian Peninsula and Bahrain), Anatolia, Asia Minor (Asian part of Turkey except Hatay Pro ...
by the 5th millennium BCE. One of the earliest examples was discovered at Tepe Pardis,
Iran
Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkmeni ...
, and dated to 5200–4700 BCE. These were made of stone or clay and secured to the ground with a peg in the center, but required significant effort to turn. True potter's wheels, which are freely-spinning and have a
wheel and axle
The wheel and axle is a simple machine consisting of a wheel attached to a smaller axle so that these two parts rotate together in which a force is transferred from one to the other. The wheel and axle can be viewed as a version of the lever, wi ...
mechanism, were developed in
Mesopotamia
Mesopotamia ''Mesopotamíā''; ar, بِلَاد ٱلرَّافِدَيْن or ; syc, ܐܪܡ ܢܗܪ̈ܝܢ, or , ) is a historical region of Western Asia situated within the Tigris–Euphrates river system, in the northern part of the F ...
(
Iraq
Iraq,; ku, عێراق, translit=Êraq officially the Republic of Iraq, '; ku, کۆماری عێراق, translit=Komarî Êraq is a country in Western Asia. It is bordered by Turkey to Iraq–Turkey border, the north, Iran to Iran–Iraq ...
) by 4200–4000 BCE. The oldest surviving example, which was found in
Ur (modern day
Iraq
Iraq,; ku, عێراق, translit=Êraq officially the Republic of Iraq, '; ku, کۆماری عێراق, translit=Komarî Êraq is a country in Western Asia. It is bordered by Turkey to Iraq–Turkey border, the north, Iran to Iran–Iraq ...
), dates to approximately 3100 BCE.
Wheels of uncertain dates have also been found in the
Indus Valley civilization
The Indus Valley Civilisation (IVC), also known as the Indus Civilisation was a Bronze Age civilisation in the northwestern regions of South Asia, lasting from 3300 BCE to 1300 BCE, and in its mature form 2600 BCE to 1900&n ...
, a 4th millennium BCE civilization covering areas of present-day India and
Pakistan
Pakistan ( ur, ), officially the Islamic Republic of Pakistan ( ur, , label=none), is a country in South Asia. It is the world's List of countries and dependencies by population, fifth-most populous country, with a population of almost 24 ...
.
The oldest indirect evidence of wheeled movement was found in the form of miniature clay wheels north of the Black Sea before 4000 BCE. From the middle of the
4th millennium BCE onward, the evidence is condensed throughout
Europe
Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...
in the form of toy cars, depictions, or ruts, with the oldest find in Northern Germany dating back to around 3400 BC. In
Mesopotamia
Mesopotamia ''Mesopotamíā''; ar, بِلَاد ٱلرَّافِدَيْن or ; syc, ܐܪܡ ܢܗܪ̈ܝܢ, or , ) is a historical region of Western Asia situated within the Tigris–Euphrates river system, in the northern part of the F ...
, depictions of wheeled
wagon
A wagon or waggon is a heavy four-wheeled vehicle pulled by draught animals or on occasion by humans, used for transporting goods, commodities, agricultural materials, supplies and sometimes people.
Wagons are immediately distinguished from ...
s found on
clay tablet
In the Ancient Near East, clay tablets (Akkadian ) were used as a writing medium, especially for writing in cuneiform, throughout the Bronze Age and well into the Iron Age.
Cuneiform characters were imprinted on a wet clay tablet with a stylu ...
pictographs
A pictogram, also called a pictogramme, pictograph, or simply picto, and in computer usage an icon, is a graphic symbol that conveys its meaning through its pictorial resemblance to a physical object. Pictographs are often used in writing and gr ...
at the
Eanna district of
Uruk
Uruk, also known as Warka or Warkah, was an ancient city of Sumer (and later of Babylonia) situated east of the present bed of the Euphrates River on the dried-up ancient channel of the Euphrates east of modern Samawah, Al-Muthannā, Iraq.Harm ...
, in the
Sumer
Sumer () is the earliest known civilization in the historical region of southern Mesopotamia (south-central Iraq), emerging during the Chalcolithic and early Bronze Ages between the sixth and fifth millennium BC. It is one of the cradles of c ...
ian civilization are dated to c. 3500–3350 BCE. In the second half of the 4th millennium BCE, evidence of wheeled vehicles appeared near-simultaneously in the Northern (
Maykop culture
The Maykop culture (, , scientific transliteration: ''Majkop,''), c. 3700 BC– 3000 BC, was a major Bronze Age archaeological culture in the western Caucasus region.
It extends along the area from the Taman Peninsula at the Kerch Strait to ne ...
) and South
Caucasus
The Caucasus () or Caucasia (), is a region between the Black Sea and the Caspian Sea, mainly comprising Armenia, Azerbaijan, Georgia, and parts of Southern Russia. The Caucasus Mountains, including the Greater Caucasus range, have historically ...
and
Eastern Europe
Eastern Europe is a subregion of the Europe, European continent. As a largely ambiguous term, it has a wide range of geopolitical, geographical, ethnic, cultural, and socio-economic connotations. The vast majority of the region is covered by Russ ...
(
Cucuteni-Trypillian culture).
![Ur chariot](https://upload.wikimedia.org/wikipedia/commons/7/7d/Ur_chariot.jpg)
Depictions of a wheeled vehicle appeared between 3631 and 3380 BCE in the
Bronocice clay pot excavated in a
Funnelbeaker culture
The Funnel(-neck-)beaker culture, in short TRB or TBK (german: Trichter(-rand-)becherkultur, nl, Trechterbekercultuur; da, Tragtbægerkultur; ) was an archaeological culture in north-central Europe.
It developed as a technological merger of lo ...
settlement in southern
Poland
Poland, officially the Republic of Poland, is a country in Central Europe. It is divided into 16 administrative provinces called voivodeships, covering an area of . Poland has a population of over 38 million and is the fifth-most populous ...
. In nearby
Olszanica, a 2.2 m wide door was constructed for wagon entry; this barn was 40 m long with three doors, dated to 5000 B.C.E—7000 years old, and belonged to the
neolithic
The Neolithic period, or New Stone Age, is an Old World archaeological period and the final division of the Stone Age. It saw the Neolithic Revolution, a wide-ranging set of developments that appear to have arisen independently in several parts ...
Linear Pottery culture
The Linear Pottery culture (LBK) is a major archaeological horizon of the European Neolithic period, flourishing . Derived from the German ''Linearbandkeramik'', it is also known as the Linear Band Ware, Linear Ware, Linear Ceramics or Inci ...
. Surviving evidence of a wheel-axle combination, from Stare Gmajne near Ljubljana in Slovenia (
Ljubljana Marshes Wooden Wheel
The Ljubljana Marshes Wheel is a wooden wheel that was found in the Ljubljana Marsh some south of Ljubljana, the capital of Slovenia, in 2002. Radiocarbon dating, performed in the VERA laboratory (Vienna Environmental Research Accelerator) in Vi ...
), is dated within two
standard deviations
In statistics, the standard deviation is a measure of the amount of variation or dispersion of a set of values. A low standard deviation indicates that the values tend to be close to the mean (also called the expected value) of the set, while ...
to 3340–3030 BCE, the axle to 3360–3045 BCE. Two types of early Neolithic European wheel and axle are known; a
circumalpine type of wagon construction (the wheel and axle rotate together, as in Ljubljana Marshes Wheel), and that of the
Baden culture
The Baden culture was a Chalcolithic archaeological culture, culture from 3520–2690 BC.
It was found in Central Europe, Central and Southeast Europe, and is in particular known from Moravia (Czech Republic), Hungary, southern Poland, Slovakia, ...
in
Hungary
Hungary ( hu, Magyarország ) is a landlocked country in Central Europe. Spanning of the Carpathian Basin, it is bordered by Slovakia to the north, Ukraine to the northeast, Romania to the east and southeast, Serbia to the south, Croatia a ...
(axle does not rotate). They both are dated to c. 3200–3000 BCE. Some historians believe that there was a diffusion of the wheeled vehicle from the
Near East
The ''Near East''; he, המזרח הקרוב; arc, ܕܢܚܐ ܩܪܒ; fa, خاور نزدیک, Xāvar-e nazdik; tr, Yakın Doğu is a geographical term which roughly encompasses a transcontinental region in Western Asia, that was once the hist ...
to Europe around the mid-4th millennium BCE.
Early wheels were simple wooden disks with a hole for the axle. Some of the earliest wheels were made from horizontal slices of tree trunks. Because of the uneven structure of
wood
Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin th ...
, a wheel made from a horizontal slice of a tree trunk will tend to be inferior to one made from rounded pieces of longitudinal boards.
The
spoke
A spoke is one of some number of rods radiating from the center of a wheel (the hub where the axle connects), connecting the hub with the round traction surface.
The term originally referred to portions of a log that had been riven (split l ...
d wheel was invented more recently and allowed the construction of lighter and swifter vehicles. The earliest known examples of wooden spoked wheels are in the context of the
Sintashta culture
The Sintashta culture (russian: Синташтинская культура, Sintashtinskaya kul'tura), around 2050–1900 BCE, is the first phase of the Sintashta–Petrovka culture. or Sintashta–Arkaim culture,. and is a late Middle Bronze Ag ...
, dating to c. 2000 BCE (
Krivoye Lake
Krivoye Ozero is a small lake in the Chelyabinsk Oblast of Russia, southeast of Magnitogorsk, near the Kazakhstan
Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country located mainly in Central Asia and partly i ...
). Soon after this, horse cultures of the
Caucasus
The Caucasus () or Caucasia (), is a region between the Black Sea and the Caspian Sea, mainly comprising Armenia, Azerbaijan, Georgia, and parts of Southern Russia. The Caucasus Mountains, including the Greater Caucasus range, have historically ...
region used horse-drawn spoked-wheel war
chariots
A chariot is a type of cart driven by a charioteer, usually using horses to provide rapid motive power. The oldest known chariots have been found in burials of the Sintashta culture in modern-day Chelyabinsk Oblast, Russia, dated to c. 2000  ...
for the greater part of three centuries. They moved deep into the Greek peninsula where they joined with the existing Mediterranean peoples to give rise, eventually, to classical Greece after the breaking of
Minoan
The Minoan civilization was a Bronze Age Aegean civilization on the island of Crete and other Aegean Islands, whose earliest beginnings were from 3500BC, with the complex urban civilization beginning around 2000BC, and then declining from 1450B ...
dominance and consolidations led by pre-classical
Sparta
Sparta ( Doric Greek: Σπάρτα, ''Spártā''; Attic Greek: Σπάρτη, ''Spártē'') was a prominent city-state in Laconia, in ancient Greece. In antiquity, the city-state was known as Lacedaemon (, ), while the name Sparta referre ...
and
Athens
Athens ( ; el, Αθήνα, Athína ; grc, Ἀθῆναι, Athênai (pl.) ) is both the capital and largest city of Greece. With a population close to four million, it is also the seventh largest city in the European Union. Athens dominates ...
.
Celt
The Celts (, see pronunciation for different usages) or Celtic peoples () are. "CELTS location: Greater Europe time period: Second millennium B.C.E. to present ancestry: Celtic a collection of Indo-European peoples. "The Celts, an ancient ...
ic chariots introduced an
iron
Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in f ...
rim around the wheel in the 1st millennium BCE.
In
China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...
, wheel tracks dating to around 2200 BCE have been found at Pingliangtai, a site of the
Longshan Culture
The Longshan (or Lung-shan) culture, also sometimes referred to as the Black Pottery Culture, was a late Neolithic culture in the middle and lower Yellow River valley areas of northern China from about 3000 to 1900 BC. The first archaeological fi ...
. Similar tracks were also found at
Yanshi
Yanshi District () is a district in the prefecture-level city of Luoyang in western Henan province, China. Yanshi lies on the Luo River and is the easternmost county-level division of Luoyang.
History
After the Zhou conquest of Shang in mid-11th ...
, a city of the
Erlitou culture
The Erlitou culture was an early Bronze Age urban society and archaeological culture that existed in the Yellow River valley from approximately 1900 to 1500 BC. A 2007 study of radiocarbon dating proposed a narrower date range of 1750 to 1530 B ...
, dating to around 1700 BCE. The earliest evidence of spoked wheels in
China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...
comes from
Qinghai
Qinghai (; alternately romanized as Tsinghai, Ch'inghai), also known as Kokonor, is a landlocked province in the northwest of the People's Republic of China. It is the fourth largest province of China by area and has the third smallest po ...
, in the form of two wheel hubs from a site dated between 2000 and 1500 BCE.
In Britain, a large wooden wheel, measuring about in diameter, was uncovered at the
Must Farm
Part of a Bronze Age settlement was uncovered at Must Farm quarry, at Whittlesey, near Peterborough, in Cambridgeshire, England. The site has been described as "Britain's Pompeii" due to its relatively good condition, including the "best-preser ...
site in East Anglia in 2016. The specimen, dating from 1,100 to 800 BCE, represents the most complete and earliest of its type found in Britain. The wheel's hub is also present. A horse's spine found nearby suggests the wheel may have been part of a horse-drawn cart. The wheel was found in a settlement built on stilts over wetland, indicating that the settlement had some sort of link to dry land.
![Remojadas Wheeled Figurine](https://upload.wikimedia.org/wikipedia/commons/d/d3/Remojadas_Wheeled_Figurine.jpg)
Although large-scale use of wheels did not occur in
the Americas prior to European contact, numerous small wheeled artifacts, identified as children's toys, have been found in Mexican archeological sites, some dating to approximately 1500 BCE. Some argue that the primary obstacle to large-scale development of the wheel in the Americas was the absence of domesticated large animals that could be used to pull wheeled carriages. The closest relative of
cattle
Cattle (''Bos taurus'') are large, domesticated, cloven-hooved, herbivores. They are a prominent modern member of the subfamily Bovinae and the most widespread species of the genus ''Bos''. Adult females are referred to as cows and adult mal ...
present in Americas in pre-Columbian times, the
American bison
The American bison (''Bison bison'') is a species of bison native to North America. Sometimes colloquially referred to as American buffalo or simply buffalo (a different clade of bovine), it is one of two extant species of bison, alongside the ...
, is difficult to domesticate and was never domesticated by Native Americans; several horse species existed until about 12,000 years ago, but ultimately became extinct. The only large animal that was domesticated in the Western hemisphere, the
llama
The llama (; ) (''Lama glama'') is a domesticated South American camelid, widely used as a List of meat animals, meat and pack animal by Inca empire, Andean cultures since the Pre-Columbian era.
Llamas are social animals and live with othe ...
, a pack animal, was not physically suited to use as a draft animal to pull wheeled vehicles, and use of the llama did not spread far beyond the
Andes
The Andes, Andes Mountains or Andean Mountains (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long, wide (widest between 18°S – 20°S ...
by the time of the arrival of Europeans.
On the other hand,
Mesoamerica
Mesoamerica is a historical region and cultural area in southern North America and most of Central America. It extends from approximately central Mexico through Belize, Guatemala, El Salvador, Honduras, Nicaragua, and northern Costa Rica. W ...
ns never developed the
wheelbarrow
A wheelbarrow is a small hand-propelled vehicle, usually with just one wheel, designed to be pushed and guided by a single person using two handles at the rear, or by a sail to push the ancient wheelbarrow by wind. The term "wheelbarrow" is mad ...
, the
potter's wheel
In pottery, a potter's wheel is a machine used in the shaping (known as throwing) of clay into round ceramic ware. The wheel may also be used during the process of trimming excess clay from leather-hard dried ware that is stiff but malleable, a ...
, nor any other practical object with a wheel or wheels.
Although present in a number of toys, very similar to those found throughout the world and still made for children today ("pull toys"),
the wheel was never put into practical use in Mesoamerica before the 16th century.
Possibly the closest the Mayas came to the utilitarian wheel is the
spindle whorl
A spindle whorl is a disc or spherical object fitted onto the spindle to increase and maintain the speed of the spin. Historically, whorls have been made of materials like amber, antler, bone, ceramic, coral, glass, stone, metal (iron, lead, lead ...
, and some scholars believe that these toys were originally made with spindle whorls and spindle sticks as "wheels" and "axes".
Aboriginal Australians
Aboriginal Australians are the various Indigenous peoples of the Australian mainland and many of its islands, such as Tasmania, Fraser Island, Hinchinbrook Island, the Tiwi Islands, and Groote Eylandt, but excluding the Torres Strait Islands ...
traditionally used circular discs rolled along the ground for use as target practice.
Nubia
Nubia () (Nobiin: Nobīn, ) is a region along the Nile river encompassing the area between the first cataract of the Nile (just south of Aswan in southern Egypt) and the confluence of the Blue and White Niles (in Khartoum in central Sudan), or ...
ns from after about 400 BCE used wheels for spinning
pottery
Pottery is the process and the products of forming vessels and other objects with clay and other ceramic materials, which are fired at high temperatures to give them a hard and durable form. Major types include earthenware, stoneware and por ...
and as
water wheels
A water wheel is a machine for converting the energy of flowing or falling water into useful forms of power, often in a watermill. A water wheel consists of a wheel (usually constructed from wood or metal), with a number of blades or buckets ...
. It is thought that Nubian waterwheels may have been ox-driven. It is also known that Nubians used horse-drawn chariots imported from
Egypt
Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Mediter ...
.
Starting from the 18th century in West Africa, wheeled vehicles were mostly used for ceremonial purposes in places like
Dahomey
The Kingdom of Dahomey () was a West African kingdom located within present-day Benin that existed from approximately 1600 until 1904. Dahomey developed on the Abomey Plateau amongst the Fon people in the early 17th century and became a region ...
.
The wheel was barely used for transportation, with the exception of
Ethiopia
Ethiopia, , om, Itiyoophiyaa, so, Itoobiya, ti, ኢትዮጵያ, Ítiyop'iya, aa, Itiyoppiya officially the Federal Democratic Republic of Ethiopia, is a landlocked country in the Horn of Africa. It shares borders with Eritrea to the ...
and
Somalia
Somalia, , Osmanya script: 𐒈𐒝𐒑𐒛𐒐𐒘𐒕𐒖; ar, الصومال, aṣ-Ṣūmāl officially the Federal Republic of SomaliaThe ''Federal Republic of Somalia'' is the country's name per Article 1 of thProvisional Constituti ...
in
Sub-Saharan Africa
Sub-Saharan Africa is, geographically, the area and regions of the continent of Africa that lies south of the Sahara. These include West Africa, East Africa, Central Africa, and Southern Africa. Geopolitically, in addition to the List of sov ...
well into the 19th century.
![TricycleAntique](https://upload.wikimedia.org/wikipedia/commons/8/82/TricycleAntique.jpg)
The spoked wheel was in continued use without major modification until the 1870s, when
wire-spoked wheel
Wire wheels, wire-spoked wheels, tension-spoked wheels, or "suspension" wheels are wheels whose rims connect to their hubs by wire spokes. Although these wires are generally stiffer than a typical wire rope, they function mechanically the sa ...
s and
pneumatic tire
A tire (American English) or tyre (British English) is a ring-shaped component that surrounds a wheel's rim to transfer a vehicle's load from the axle through the wheel to the ground and to provide traction on the surface over which ...
s were invented. Pneumatic tires can greatly reduce rolling resistance and improve comfort. Wire spokes are under tension, not compression, making it possible for the wheel to be both stiff and light. Early radially-spoked wire wheels gave rise to tangentially-spoked wire wheels, which were widely used on cars into the late 20th century. Cast
alloy wheels
In the automotive industry, alloy wheels are wheels that are made from an alloy of aluminium or magnesium. Alloys are mixtures of a metal and other elements. They generally provide greater strength over pure metals, which are usually much softe ...
are now more commonly used; forged alloy wheels are used when weight is critical.
The invention of the wheel has also been important for
technology
Technology is the application of knowledge to reach practical goals in a specifiable and reproducible way. The word ''technology'' may also mean the product of such an endeavor. The use of technology is widely prevalent in medicine, science, ...
in general, important applications including the
water wheel
A water wheel is a machine for converting the energy of flowing or falling water into useful forms of power, often in a watermill. A water wheel consists of a wheel (usually constructed from wood or metal), with a number of blades or buckets ...
, the
cogwheel (see also
antikythera mechanism
The Antikythera mechanism ( ) is an Ancient Greece, Ancient Greek hand-powered orrery, described as the oldest example of an analogue computer used to predict astronomy, astronomical positions and eclipses decades in advance. It could also be ...
), the
spinning wheel
A spinning wheel is a device for spinning thread or yarn from fibres. It was fundamental to the cotton textile industry prior to the Industrial Revolution. It laid the foundations for later machinery such as the spinning jenny and spinning f ...
, and the
astrolabe
An astrolabe ( grc, ἀστρολάβος ; ar, ٱلأَسْطُرلاب ; persian, ستارهیاب ) is an ancient astronomical instrument that was a handheld model of the universe. Its various functions also make it an elaborate inclin ...
or
torquetum
The ''torquetum'' or turquet is a medieval astronomical instrument designed to take and convert measurements made in three sets of coordinates: Horizon, equatorial, and ecliptic. It is said to be a combination of Ptolemy's astrolabon and the p ...
. More modern descendants of the wheel include the
propeller
A propeller (colloquially often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon ...
, the
jet engine
A jet engine is a type of reaction engine discharging a fast-moving jet of heated gas (usually air) that generates thrust by jet propulsion. While this broad definition can include rocket, Pump-jet, water jet, and hybrid propulsion, the term ...
, the
flywheel
A flywheel is a mechanical device which uses the conservation of angular momentum to store rotational energy; a form of kinetic energy proportional to the product of its moment of inertia and the square of its rotational speed. In particular, ass ...
(
gyroscope
A gyroscope (from Ancient Greek γῦρος ''gŷros'', "round" and σκοπέω ''skopéō'', "to look") is a device used for measuring or maintaining orientation and angular velocity. It is a spinning wheel or disc in which the axis of rota ...
) and the
turbine
A turbine ( or ) (from the Greek , ''tyrbē'', or Latin ''turbo'', meaning vortex) is a rotary mechanical device that extracts energy from a fluid flow and converts it into useful work. The work produced by a turbine can be used for generating e ...
.
Mechanics and function
A wheeled vehicle requires much less work to move than simply dragging the same weight. The low resistance to motion is explained by the fact that the
frictional work done is no longer at the surface that the vehicle is traversing, but in the
bearings. In the simplest and oldest case the bearing is just a round hole through which the axle passes (a "
plain bearing
A plain bearing, or more commonly sliding contact bearing and slide bearing (in railroading sometimes called a solid bearing, journal bearing, or friction bearing), is the simplest type of bearing, comprising just a bearing surface and no rolli ...
"). Even with a plain bearing, the frictional work is greatly reduced because:
* The normal force at the sliding interface is same as with simple dragging.
* The sliding distance is reduced for a given distance of travel.
* The coefficient of friction at the interface is usually lower.
Example:
* If a 100 kg object is dragged for 10 m along a surface with the
coefficient of friction
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. There are several types of friction:
*Dry friction is a force that opposes the relative lateral motion of ...
''μ'' = 0.5, the
normal force
In mechanics, the normal force F_n is the component of a contact force that is perpendicular to the surface that an object contacts, as in Figure 1. In this instance ''normal'' is used in the geometric sense and means perpendicular, as oppose ...
is 981
N and the
work
Work may refer to:
* Work (human activity), intentional activity people perform to support themselves, others, or the community
** Manual labour, physical work done by humans
** House work, housework, or homemaking
** Working animal, an animal tr ...
done (required
energy
In physics, energy (from Ancient Greek: ἐνέργεια, ''enérgeia'', “activity”) is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of heat a ...
) is (work=force x distance) 981 × 0.5 × 10 = 4905
joule
The joule ( , ; symbol: J) is the unit of energy in the International System of Units (SI). It is equal to the amount of work done when a force of 1 newton displaces a mass through a distance of 1 metre in the direction of the force applied ...
s.
* Now give the object 4 wheels. The normal force between the 4 wheels and axles is the same (in total) 981 N. Assume, for wood, ''μ'' = 0.25, and say the wheel
diameter
In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints lie on the circle. It can also be defined as the longest chord of the circle. Both definitions are also valid for ...
is 1000 mm and axle diameter is 50 mm. So while the object still moves 10 m the sliding frictional surfaces only slide over each other a distance of 0.5 m. The work done is 981 × 0.25 × 0.5 = 123 joules; the work done has reduced to 1/40 of that of dragging.
Additional energy is lost from the wheel-to-road interface. This is termed
rolling resistance
Rolling resistance, sometimes called rolling friction or rolling drag, is the force resisting the motion when a body (such as a ball, tire, or wheel) rolls on a surface. It is mainly caused by non-elastic effects; that is, not all the energy nee ...
which is predominantly a deformation loss. It depends on the nature of the ground, of the material of the wheel, its inflation in the case of a tire, the net torque exerted by the eventual engine, and many other factors.
A wheel can also offer advantages in traversing irregular surfaces if the wheel radius is sufficiently large compared to the irregularities.
The wheel alone is not a machine, but when attached to an
axle
An axle or axletree is a central shaft for a rotating wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to the vehicle, with the wheels rotating around the axle. In the former case, bearing ...
in conjunction with bearing, it forms the
wheel and axle
The wheel and axle is a simple machine consisting of a wheel attached to a smaller axle so that these two parts rotate together in which a force is transferred from one to the other. The wheel and axle can be viewed as a version of the lever, wi ...
, one of the
simple machine
A simple machine is a mechanical device that changes the direction or magnitude of a force. In general, they can be defined as the simplest mechanisms that use mechanical advantage (also called leverage) to multiply force. Usually the term refer ...
s. A driven wheel is an example of a wheel and axle. Wheels pre-date driven wheels by about 6000 years, themselves an evolution of using round logs as rollers to move a heavy load—a practice going back in pre-history so far that it has not been dated.
Construction
Rim
![AluminumWheel spoke design](https://upload.wikimedia.org/wikipedia/commons/5/53/AluminumWheel_spoke_design.jpg)
The rim is the "outer edge of a wheel, holding the tire". It makes up the outer circular design of the wheel on which the inside edge of the
tire
A tire (American English) or tyre (British English) is a ring-shaped component that surrounds a Rim (wheel), wheel's rim to transfer a vehicle's load from the axle through the wheel to the ground and to provide Traction (engineering), t ...
is mounted on vehicles such as
automobile
A car or automobile is a motor vehicle with Wheel, wheels. Most definitions of ''cars'' say that they run primarily on roads, Car seat, seat one to eight people, have four wheels, and mainly transport private transport#Personal transport, pe ...
s. For example, on a
bicycle wheel
A bicycle wheel is a wheel, most commonly a wire wheel, designed for a bicycle. A pair is often called a wheelset, especially in the context of ready built "off the shelf" performance-oriented wheels.
Bicycle wheels are typically designed ...
the
rim is a large hoop attached to the outer ends of the spokes of the wheel that holds the tire and tube.
In the 1st millennium BCE an
iron
Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in f ...
rim was introduced around the wooden wheels of
chariot
A chariot is a type of cart driven by a charioteer, usually using horses to provide rapid motive power. The oldest known chariots have been found in burials of the Sintashta culture in modern-day Chelyabinsk Oblast, Russia, dated to c. 2000&nbs ...
s.
Hub
The hub is the center of the wheel, and typically houses a
bearing, and is where the spokes meet.
A
hubless wheel
A centreless wheel is a wheel that lacks a centre or hub, instead being supported and driven at the rim.
Design
Centreless wheels are toroidal in shape and have one or multiple bearings along the rim. Propulsion can be achieved in diffe ...
(also known as a rim-rider or centerless wheel) is a type of wheel with no center
hub. More specifically, the hub is actually almost as big as the wheel itself. The
axle
An axle or axletree is a central shaft for a rotating wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to the vehicle, with the wheels rotating around the axle. In the former case, bearing ...
is hollow, following the wheel at very close
tolerances
Engineering tolerance is the permissible limit or limits of variation in:
# a physical dimension;
# a measured value or physical property of a material, manufacturing, manufactured object, system, or service;
# other measured values (such as t ...
.
Spokes
![Wheel Iran](https://upload.wikimedia.org/wikipedia/commons/e/e6/Wheel_Iran.jpg)
A ''spoke'' is one of some number of rods radiating from the center of a wheel (the
hub where the
axle
An axle or axletree is a central shaft for a rotating wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to the vehicle, with the wheels rotating around the axle. In the former case, bearing ...
connects), connecting the hub with the round traction surface. The term originally referred to portions of a log which had been split lengthwise into four or six sections. The radial members of a wagon wheel were made by carving a spoke (from a log) into their finished shape. A
spokeshave
A spokeshave is a hand tool used to shape and smooth woods in woodworking jobs such as making cart wheel spokes, chair legs, paddles, bows, and arrows. The tool consists of a blade fixed into the body of the tool, which has a handle for each han ...
is a
tool
A tool is an object that can extend an individual's ability to modify features of the surrounding environment or help them accomplish a particular task. Although many animals use simple tools, only human beings, whose use of stone tools dates ba ...
originally developed for this purpose. Eventually, the term spoke was more commonly applied to the finished product of the
wheelwright
A wheelwright is a craftsman who builds or repairs wooden wheels. The word is the combination of "wheel" and the word "wright", (which comes from the Old English word "''wryhta''", meaning a worker or shaper of wood) as in shipwright and arkw ...
's work, than to the materials used.
Wire
The
rims of ''wire wheels'' (or "wire spoked wheels") are connected to their hubs by wire
spoke
A spoke is one of some number of rods radiating from the center of a wheel (the hub where the axle connects), connecting the hub with the round traction surface.
The term originally referred to portions of a log that had been riven (split l ...
s. Although these
wire
Overhead power cabling. The conductor consists of seven strands of steel (centre, high tensile strength), surrounded by four outer layers of aluminium (high conductivity). Sample diameter 40 mm
A wire is a flexible strand of metal.
Wire is c ...
s are generally stiffer than a typical
wire rope
Steel wire rope (right hand lang lay)
Wire rope is several strands of metal wire twisted into a helix forming a composite
''rope'', in a pattern known as ''laid rope''. Larger diameter wire rope consists of multiple strands of such laid rope in a ...
, they function mechanically the same as
tensioned flexible wires, keeping the rim true while supporting applied loads.
Wire wheels are used on most
bicycle
A bicycle, also called a pedal cycle, bike or cycle, is a human-powered or motor-powered assisted, pedal-driven, single-track vehicle, having two wheels attached to a frame, one behind the other. A is called a cyclist, or bicyclist.
Bic ...
s and still used on many
motorcycles
A motorcycle (motorbike, bike, or trike (if three-wheeled)) is a two or three-wheeled motor vehicle steered by a handlebar. Motorcycle design varies greatly to suit a range of different purposes: long-distance travel, commuting, cruising, ...
. They were invented by aeronautical engineer
George Cayley
Sir George Cayley, 6th Baronet (27 December 1773 – 15 December 1857) was an English engineer, inventor, and aviator. He is one of the most important people in the history of aeronautics. Many consider him to be the first true scientific aeri ...
and first used in bicycles by
James Starley
James Starley (21 April 1830 – 17 June 1881) was an English inventor and father of the bicycle industry. He was one of the most innovative and successful builders of bicycles and tricycles. His inventions include the differential gear and t ...
. A process of assembling wire wheels is described as
wheelbuilding
Wheelbuilding is the process of assembling wire wheels (generally a bicycle wheel, but including wheelchairs, and some cars). The components of a wire wheel are the rim, spokes, nipples, and hub.
Goals
The wheelwright must ensure that the whe ...
.
Tire/Tyre
![BMW tire](https://upload.wikimedia.org/wikipedia/commons/9/93/BMW_tire.jpg)
A tire (in
American English
American English, sometimes called United States English or U.S. English, is the set of variety (linguistics), varieties of the English language native to the United States. English is the Languages of the United States, most widely spoken lan ...
and
Canadian English
Canadian English (CanE, CE, en-CA) encompasses the varieties of English native to Canada. According to the 2016 census, English was the first language of 19.4 million Canadians or 58.1% of the total population; the remainder spoke French ( ...
) or tyre (in some
Commonwealth Nations
The Commonwealth of Nations, simply referred to as the Commonwealth, is a political association of 56 member states, the vast majority of which are former territories of the British Empire. The chief institutions of the organisation are the Co ...
such as UK,
India
India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...
,
South Africa
South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...
,
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
and
New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...
) is a ring-shaped covering that fits around a wheel
rim to protect it and enable better vehicle performance by providing a flexible cushion that absorbs shock while keeping the wheel in close contact with the ground. The word itself may be derived from the word "tie", which refers to the outer steel ring part of a wooden cart wheel that ties the wood segments together (see
Etymology
Etymology ()The New Oxford Dictionary of English (1998) – p. 633 "Etymology /ˌɛtɪˈmɒlədʒi/ the study of the class in words and the way their meanings have changed throughout time". is the study of the history of the Phonological chan ...
above).
The fundamental materials of modern tires are
synthetic rubber
A synthetic rubber is an artificial elastomer. They are polymers synthesized from petroleum byproducts. About 32-million metric tons of rubbers are produced annually in the United States, and of that amount two thirds are synthetic. Synthetic rubbe ...
,
natural rubber
Rubber, also called India rubber, latex, Amazonian rubber, ''caucho'', or ''caoutchouc'', as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds. Thailand, Malaysia, and ...
, fabric, and wire, along with other compound chemicals. They consist of a tread and a body. The tread provides
traction while the body ensures support. Before rubber was invented, the first versions of tires were simply bands of metal that fitted around wooden wheels to prevent wear and tear. Today, the vast majority of tires are
pneumatic
Pneumatics (from Greek ‘wind, breath’) is a branch of engineering that makes use of gas or pressurized air.
Pneumatic systems used in Industrial sector, industry are commonly powered by compressed air or compressed inert gases. A central ...
inflatable structure
An inflatable is an object that can be inflated with a gas, usually with air, but hydrogen, helium and nitrogen are also used. One of several advantages of an inflatable is that it can be stored in a small space when not inflated, since inflata ...
s, comprising a doughnut-shaped body of cords and wires encased in rubber and generally filled with compressed air to form an inflatable cushion. Pneumatic tires are used on many types of vehicles, such as
car
A car or automobile is a motor vehicle with wheels. Most definitions of ''cars'' say that they run primarily on roads, seat one to eight people, have four wheels, and mainly transport people instead of goods.
The year 1886 is regarded as ...
s,
bicycle
A bicycle, also called a pedal cycle, bike or cycle, is a human-powered or motor-powered assisted, pedal-driven, single-track vehicle, having two wheels attached to a frame, one behind the other. A is called a cyclist, or bicyclist.
Bic ...
s,
motorcycles
A motorcycle (motorbike, bike, or trike (if three-wheeled)) is a two or three-wheeled motor vehicle steered by a handlebar. Motorcycle design varies greatly to suit a range of different purposes: long-distance travel, commuting, cruising, ...
,
truck
A truck or lorry is a motor vehicle designed to transport cargo, carry specialized payloads, or perform other utilitarian work. Trucks vary greatly in size, power, and configuration, but the vast majority feature body-on-frame construction ...
s,
earthmovers, and
aircraft
An aircraft is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines ...
.
Protruding or covering attachments
Extreme
off-road
Off-roading is the activity of driving or riding in a vehicle on unpaved surfaces such as sand, gravel, riverbeds, mud, snow, rocks, and other natural terrain. Types of off-roading range in intensity, from leisure drives with unmodified vehicl ...
conditions have resulted in the invention of several types of wheel cover, which may be constructed as removable attachments or as permanent covers. Wheels like this are no longer necessarily round, or have panels that make the ground-contact area flat.
Examples include:
*
Snow chains
Snow chains, or tire chains, are devices fitted to the tires of vehicles to provide increased traction when driving through snow and ice.
Snow chains attach to the drive wheels of a vehicle or special systems deploy chains which swing under ...
- Specially designed chain assemblies that wrap around the tire to provide increased grip, designed for deep snow.
*
Dreadnaught wheel - A type of permanently attached hinged panels for general extreme off-road use. These are not connected directly to the wheels, but to each other.
*
Pedrail wheel
The pedrail wheel is a type of all-terrain wheel developed in the late 19th and early 20th century by Londoner Bramah Joseph Diplock. It consists of a series of "feet" (''pedes'' in Latin) connected to pivots on a wheel. As the wheel travels, ...
- A system of rails that holds panels that hold the vehicle. These do not necessarily have to be built as a circle (wheel) and are thus also a form of
Continuous track
Continuous track is a system of vehicle propulsion used in tracked vehicles, running on a continuous band of treads or track plates driven by two or more wheels. The large surface area of the tracks distributes the weight of the vehicle b ...
.
*A version of the above examples (name unknown to the writer) was commonly used on heavy
artillery
Artillery is a class of heavy military ranged weapons that launch munitions far beyond the range and power of infantry firearms. Early artillery development focused on the ability to breach defensive walls and fortifications during siege ...
during
World War I
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...
. Specific examples:
Cannone da 149/35 A
The Cannone da 149/35 A was a heavy gun which served with Italy during World War I and World War II. It was already an old-fashioned weapon when introduced around 1900. It lacked a recoil system of any kind and could not traverse. The gun recoiled ...
and the
Big Bertha. These were panels that were connected to each other by multiple hinges and could be installed over a contemporary wheel.
*
Continuous track
Continuous track is a system of vehicle propulsion used in tracked vehicles, running on a continuous band of treads or track plates driven by two or more wheels. The large surface area of the tracks distributes the weight of the vehicle b ...
- A system of linked and hinged chains/panels that cover multiple wheels in a way that allows the vehicles mass to be distributed across the space between wheels that are positioned in front of / behind other wheels.
*"Tire totes" - A bag designed to cover a tire to improve traction in deep snow.
Truck and bus wheels may block (stop rotating) under certain circumstances, such as brake system failure. To help detect this, they sometimes feature "wheel rotation indicators": colored strips of plastic attached to the rim and protruding out from it, such that they can be seen by the driver in the
side-view mirrors. These devices were invented and patented in 1998 by a Canadian truck shop owner.
Alternatives
While wheels are very widely used for ground transport, there are alternatives, some of which are suitable for terrain where wheels are ineffective. Alternative methods for ground transport without wheels include:
*
Maglev
Maglev (derived from '' magnetic levitation''), is a system of train transportation that uses two sets of electromagnets: one set to repel and push the train up off the track, and another set to move the elevated train ahead, taking advantage ...
*
Sled
A sled, skid, sledge, or sleigh is a land vehicle that slides across a surface, usually of ice or snow. It is built with either a smooth underside or a separate body supported by two or more smooth, relatively narrow, longitudinal runners ...
,
ski
A ski is a narrow strip of semi-rigid material worn underfoot to glide over snow. Substantially longer than wide and characteristically employed in pairs, skis are attached to ski boots with ski bindings, with either a free, lockable, or partial ...
or
travois
A travois (; Canadian French, from French , a frame for restraining horses; also obsolete travoy or travoise) is a historical frame structure that was used by indigenous peoples, notably the Plains Aboriginals of North America, to drag loads ov ...
*
Hovercraft
A hovercraft, also known as an air-cushion vehicle or ACV, is an amphibious Craft (vehicle), craft capable of travelling over land, water, mud, ice, and other surfaces.
Hovercraft use blowers to produce a large volume of air below the hull ...
and
ekranoplan
A ground-effect vehicle (GEV), also called a wing-in-ground-effect (WIG), ground-effect craft, wingship, flarecraft or ekranoplan (russian: экранопла́н – "screenglider"), is a vehicle that is able to move over the surface by gainin ...
s
*
Walking
Walking (also known as ambulation) is one of the main gaits of terrestrial locomotion among legged animals. Walking is typically slower than running and other gaits. Walking is defined by an 'inverted pendulum' gait in which the body vaults o ...
pedestrian
A pedestrian is a person traveling on foot, whether walking or running. In modern times, the term usually refers to someone walking on a road or pavement, but this was not the case historically.
The meaning of pedestrian is displayed with ...
,
Litter (vehicle)
The litter is a class of wheelless vehicles, a type of human-powered transport, for the transport of people. Smaller litters may take the form of open chairs or beds carried by two or more carriers, some being enclosed for protection from the el ...
or a
walking machine
*
Horse riding
Equestrianism (from Latin , , , 'horseman', 'horse'), commonly known as horse riding (Commonwealth English) or horseback riding (American English), includes the disciplines of riding, Driving (horse), driving, and Equestrian vaulting, vaulting ...
*
Caterpillar tracks
Continuous track is a system of vehicle propulsion used in tracked vehicles, running on a continuous band of treads or track plates driven by two or more wheels. The large surface area of the tracks distributes the weight of the vehicle b ...
(operated by wheels)
*
Pedrail
The pedrail wheel is a type of all-terrain wheel developed in the late 19th and early 20th century by Londoner Bramah Joseph Diplock. It consists of a series of "feet" (''pedes'' in Latin) connected to pivots on a wheel. As the wheel travels, ...
wheels, using aspects of both wheel and caterpillar track
*
Sphere
A sphere () is a Geometry, geometrical object that is a solid geometry, three-dimensional analogue to a two-dimensional circle. A sphere is the Locus (mathematics), set of points that are all at the same distance from a given point in three ...
s, as used by
Dyson Dyson may refer to:
* Dyson (surname), people with the surname Dyson
* Dyson (company), a Singaporean multinational home appliances company founded by James Dyson
* Dyson (crater), a crater on the Moon
* Dyson (operating system), a Unix general-pur ...
vacuum cleaners and
hamster ball
Hamster balls are hollow spheres made of clear plastic into which hamsters, gerbils, degus and other small rodent pets are placed, allowing them to run around outside their cages without the risk of running away or getting lost under furniture. ...
s
*
Screw-propelled vehicle
A screw-propelled vehicle is a land or amphibious vehicle designed to cope with difficult terrain, such as snow, ice, mud, and swamp. Such vehicles are distinguished by being moved by the rotation of one or more auger-like cylinders fitted ...
Symbolism
![Jain Cosmic Time Cycle](https://upload.wikimedia.org/wikipedia/commons/4/48/Jain_Cosmic_Time_Cycle.jpg)
The wheel has also become a strong cultural and spiritual metaphor for a cycle or regular repetition (see
chakra
Chakras (, ; sa , text=चक्र , translit=cakra , translit-std=IAST , lit=wheel, circle; pi, cakka) are various focal points used in a variety of ancient meditation practices, collectively denominated as Tantra, or the esoteric or ...
,
reincarnation
Reincarnation, also known as rebirth or transmigration, is the philosophical or religious concept that the non-physical essence of a living being begins a new life in a different physical form or body after biological death. Resurrection is a ...
,
Yin and Yang
Yin and yang ( and ) is a Chinese philosophy, Chinese philosophical concept that describes opposite but interconnected forces. In Chinese cosmology, the universe creates itself out of a primary chaos of material energy, organized into the c ...
among others). As such and because of the difficult terrain, wheeled vehicles were forbidden in
old Tibet. The wheel in ancient
China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...
is seen as a symbol of health and strength and used by some villages as a tool to predict future health and success. The
diameter
In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints lie on the circle. It can also be defined as the longest chord of the circle. Both definitions are also valid for ...
of the wheel is indicator of one's future health. The
Kalachakra
''Kālacakra'' () is a polysemic term in Vajrayana Buddhism that means "wheel of time" or "time cycles". "''Kālacakra''" is also the name of a series of Buddhist texts and a major practice lineage in Indian Buddhism and Tibetan Buddhism. The ta ...
or wheel of time is also a subject in some forms of
Buddhism
Buddhism ( , ), also known as Buddha Dharma and Dharmavinaya (), is an Indian religion or philosophical tradition based on teachings attributed to the Buddha. It originated in northern India as a -movement in the 5th century BCE, and gra ...
, along with the
dharmachakra
The dharmachakra (Sanskrit: धर्मचक्र; Pali: ''dhammacakka'') or wheel of dharma is a widespread symbol used in Indian religions such as Hinduism, Jainism, and especially Buddhism.John C. Huntington, Dina Bangdel, ''The Circle o ...
.
[John C. Huntington, Dina Bangdel, ''The Circle of Bliss: Buddhist Meditational Art,'' p. 524.
]
The
winged wheel
A winged wheel is a symbol used historically on monuments by the Ancient Greeks and Romans and more recently as a heraldic charge. The symbol was associated with the Ancient Greek god Hermes and as a representation of the chariot (or velocipede) ...
is a symbol of progress, seen in many contexts including the
coat of arms of Panama
The Panamanian coat of arms is a heraldic symbol for Panama. These arms were adopted provisionally and then definitively by the same laws that adopted the Panamanian flag.
The harpy eagle (''Harpia harpyja''), the Panamanian national bird, is th ...
, the logo of the
Ohio State Highway Patrol
The Ohio State Highway Patrol is a division of the Ohio Department of Public Safety and has the primary responsibility of traffic enforcement in the state of Ohio.
Divisions
Operationally, the Patrol is divided into units whose varying tasks com ...
and the
State Railway of Thailand
The State Railway of Thailand (SRT) ( th, การรถไฟแห่งประเทศไทย, abbrev. รฟท., ) is the state-owned rail operator under the jurisdiction of the Ministry of Transport in Thailand.
History
The SRT was ...
. The wheel is also the prominent figure on the
flag of India
The national flag of India, Colloquialism, colloquially called the tricolour, is a horizontal rectangular tricolour flag of Saffron (color)#India saffron, India saffron, white and Variations of green#India green, India green; with the ', a 24 ...
. The wheel in this case represents law (
dharma
Dharma (; sa, धर्म, dharma, ; pi, dhamma, italic=yes) is a key concept with multiple meanings in Indian religions, such as Hinduism, Buddhism, Jainism, Sikhism and others. Although there is no direct single-word translation for '' ...
). It also appears in the
flag of the Romani people
The Romani flag or the flag of the Roma ( rom, O styago le romengo, or ''O romanko flako'') is the international ethnic flag of the Romani people, historically known as "Gypsies", which form a stateless minority in countries across Eurasia, Afric ...
, hinting to their nomadic history and their Indian origins.
The introduction of spoked (
chariot
A chariot is a type of cart driven by a charioteer, usually using horses to provide rapid motive power. The oldest known chariots have been found in burials of the Sintashta culture in modern-day Chelyabinsk Oblast, Russia, dated to c. 2000&nbs ...
) wheels in the Middle Bronze Age appears to have carried somewhat of a prestige. The
sun cross
A sun cross, solar cross, or wheel cross is a solar symbol consisting of an equilateral cross inside a circle.
The design is frequently found in the symbolism of prehistoric cultures, particularly during the Neolithic to Bronze Age periods of ...
appears to have a significance in
Bronze Age religion, replacing the earlier concept of a
solar barge
Solar barques were the vessels used by the sun god Ra in ancient Egyptian mythology. During the day, Ra was said to use a vessel called the Mandjet ( egy, mꜥnḏt) or the Boat of Millions of Years ( egy, wjꜣ-n-ḥḥw), and the vessel he ...
with the more 'modern' and technologically advanced
solar chariot
A solar deity or sun deity is a deity who represents the Sun, or an aspect of it. Such deities are usually associated with power and strength. Solar deities and Sun worship can be found throughout most of recorded history in various forms. Th ...
. The wheel was also a solar symbol for the
Ancient Egyptians.
In modern usage, the 'invention of the wheel' can be considered as a symbol of one of the first technologies of early civilization, alongside farming and metalwork, and thus be used as a benchmark to grade the level of societal progress.
Some
Neopagans
Modern paganism, also known as contemporary paganism and neopaganism, is a term for a religion or family of religions influenced by the various historical pre-Christian beliefs of pre-modern peoples in Europe and adjacent areas of North Afric ...
such as
Wicca
Wicca () is a modern Pagan religion. Scholars of religion categorise it as both a new religious movement and as part of the occultist stream of Western esotericism. It was developed in England during the first half of the 20th century and was ...
ns have adopted the
Wheel of the Year
The Wheel of the Year is an annual cycle of seasonal festivals, observed by many modern pagans, consisting of the year's chief solar events (solstices and equinoxes) and the midpoints between them. While names for each festival vary among dive ...
into their religious practices.
See also
* Types:
Alloy wheel
In the automotive industry, alloy wheels are wheels that are made from an alloy of aluminium or magnesium. Alloys are mixtures of a metal and other elements. They generally provide greater strength over pure metals, which are usually much soft ...
,
Artillery wheel
The artillery wheel was a nineteenth-century and early-twentieth-century style of wagon, gun carriage, and automobile wheel. Rather than having its spokes mortised into a wooden nave (hub), it has them fitted together in a keystone fashion with m ...
,
Ball transfer unit
Ball transfer units are omnidirectional load-bearing spherical balls mounted inside a restraining fixture. They are identical in principle to a computer trackball (pointing device). Typically the design involves a single large ball supported by s ...
,
Bicycle wheel
A bicycle wheel is a wheel, most commonly a wire wheel, designed for a bicycle. A pair is often called a wheelset, especially in the context of ready built "off the shelf" performance-oriented wheels.
Bicycle wheels are typically designed ...
,
Caster
A caster (or castor) is an undriven wheel that is designed to be attached to the bottom of a larger object (the "vehicle") to enable that object to be moved.
Casters are used in numerous applications, including shopping carts, office chairs, t ...
,
Cogwheel,
Dreadnaught wheel,
Driving wheel
On a steam locomotive, a driving wheel is a powered wheel which is driven by the locomotive's pistons (or turbine, in the case of a steam turbine locomotive). On a conventional, non-articulated locomotive, the driving wheels are all coupled ...
,
Flywheel
A flywheel is a mechanical device which uses the conservation of angular momentum to store rotational energy; a form of kinetic energy proportional to the product of its moment of inertia and the square of its rotational speed. In particular, ass ...
,
Hubless wheel
A centreless wheel is a wheel that lacks a centre or hub, instead being supported and driven at the rim.
Design
Centreless wheels are toroidal in shape and have one or multiple bearings along the rim. Propulsion can be achieved in diffe ...
,
Inline skate wheel,
Mansell wheel
The Mansell Wheel is a railway wheel patented by Richard Mansell, the Carriage and Wagon superintendent of the South Eastern Railway in the UK. The design was created in the 1840s and was eventually widely used on passenger railway stock in the ...
,
Mecanum wheel
The mecanum wheel is an omnidirectional wheel design for a land-based vehicle to move in any direction. It is sometimes called the Swedish wheel or Ilon wheel after its inventor, Bengt Erland Ilon (1923–2008), who conceived of the concept w ...
,
Motorcycle wheel
Motorcycle wheels are made to cope with radial and axial forces. They also provide a way of mounting other critical components such as the brakes, final drive and suspension. Wheels, and anything directly connected to them, are considered to be un ...
,
Omni wheel
Omni wheels or poly wheels, similar to Mecanum wheels, are wheels with small discs (called rollers) around the circumference which are perpendicular to the turning direction. The effect is that the wheel can be driven with full force, but will a ...
,
Pedrail wheel
The pedrail wheel is a type of all-terrain wheel developed in the late 19th and early 20th century by Londoner Bramah Joseph Diplock. It consists of a series of "feet" (''pedes'' in Latin) connected to pivots on a wheel. As the wheel travels, ...
,
Pressed Steel wheel,
Skateboard wheel,
Square wheel
A square wheel is a wheel that, instead of being circular, has the shape of a square. While literal square wheels exist, a more common use is as an idiom meaning feeling bad and naive (see reinventing the wheel).
A square wheel can roll smoothly ...
,
Stairclimber wheel,
Steering wheel
A steering wheel (also called a driving wheel (UK), a hand wheel, or simply wheel) is a type of steering control in vehicles.
Steering wheels are used in most modern land vehicles, including all mass-production automobiles, buses, light and ...
(
Ship's wheel
A ship's wheel or boat's wheel is a device used aboard a water vessel to steer that vessel and control its course. Together with the rest of the steering mechanism, it forms part of the helm. It is connected to a mechanical, electric servo, or h ...
),
Train wheel
A train wheel or rail wheel is a type of wheel specially designed for use on railway tracks. The wheel acts as a rolling component, typically press fitted onto an axle and mounted directly on a railway carriage or locomotive, or indirectly on a b ...
,
Tweel
The Tweel (a portmanteau of ''tire'' and ''wheel'') is an airless tire design developed by the France, French tire company Michelin. Its significant advantage over pneumatic tires is that the Tweel does not use a bladder full of compressed air ...
,
Wagon wheel,
Wire wheel
Wire wheels, wire-spoked wheels, tension-spoked wheels, or "suspension" wheels are wheels whose rims connect to their hubs by wire spokes. Although these wires are generally stiffer than a typical wire rope, they function mechanically the sam ...
* Components:
Axle
An axle or axletree is a central shaft for a rotating wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to the vehicle, with the wheels rotating around the axle. In the former case, bearing ...
,
Bogie
A bogie ( ) (in some senses called a truck in North American English) is a chassis or framework that carries a wheelset, attached to a vehicle—a modular subassembly of wheels and axles. Bogies take various forms in various modes of transp ...
/
Truck
A truck or lorry is a motor vehicle designed to transport cargo, carry specialized payloads, or perform other utilitarian work. Trucks vary greatly in size, power, and configuration, but the vast majority feature body-on-frame construction ...
,
Differential,
Drive shaft
A drive shaft, driveshaft, driving shaft, tailshaft (Australian English), propeller shaft (prop shaft), or Cardan shaft (after Girolamo Cardano) is a component for transmitting mechanical power (physics), power and torque and rotation, usually ...
,
Drivetrain
A drivetrain (also frequently spelled as drive train or sometimes drive-train) is the group of components that deliver mechanical power from the prime mover to the driven components. In automotive engineering, the drivetrain is the components o ...
,
Rim,
Snow chains
Snow chains, or tire chains, are devices fitted to the tires of vehicles to provide increased traction when driving through snow and ice.
Snow chains attach to the drive wheels of a vehicle or special systems deploy chains which swing under ...
,
Spoke
A spoke is one of some number of rods radiating from the center of a wheel (the hub where the axle connects), connecting the hub with the round traction surface.
The term originally referred to portions of a log that had been riven (split l ...
,
Tire
A tire (American English) or tyre (British English) is a ring-shaped component that surrounds a Rim (wheel), wheel's rim to transfer a vehicle's load from the axle through the wheel to the ground and to provide Traction (engineering), t ...
,
Wheelset
* Related technologies and concepts:
Archimedes screw
The Archimedes screw, also known as the Archimedean screw, hydrodynamic screw, water screw or Egyptian screw, is one of the earliest hydraulic machines. Using Archimedes screws as water pumps (Archimedes screw pump (ASP) or screw pump) dates back ...
,
Barrel
A barrel or cask is a hollow cylindrical container with a bulging center, longer than it is wide. They are traditionally made of wooden staves and bound by wooden or metal hoops. The word vat is often used for large containers for liquids, ...
,
Breaking wheel
The breaking wheel or execution wheel, also known as the Wheel of Catherine or simply the Wheel, was a torture method used for public execution primarily in Europe from antiquity through the Middle Ages into the early modern period by breakin ...
,
Color wheel
A color wheel or color circle is an abstract illustrative organization of color hues around a circle, which shows the relationships between primary colors, secondary colors, tertiary colors etc.
Some sources use the terms ''color wheel'' & ' ...
,
Compact disc
The compact disc (CD) is a Digital media, digital optical disc data storage format that was co-developed by Philips and Sony to store and play digital audio recordings. In August 1982, the first compact disc was manufactured. It was then rele ...
,
Ferris wheel
A Ferris wheel (also called a Giant Wheel or an observation wheel) is an amusement ride consisting of a rotating upright wheel with multiple passenger-carrying components (commonly referred to as passenger cars, cabins, tubs, gondolas, capsules ...
,
Pottery wheel
In pottery, a potter's wheel is a machine used in the shaping (known as throwing) of clay into round ceramic ware. The wheel may also be used during the process of trimming excess clay from leather-hard dried ware that is stiff but malleable, ...
,
Propeller
A propeller (colloquially often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon ...
,
Reinventing the wheel
To reinvent the wheel is to attempt to duplicate—most likely with inferior results—a basic method that has already previously been created or optimized by others.
The inspiration for this idiomatic metaphor is that the wheel is an ancient ar ...
,
Spindle whorl
A spindle whorl is a disc or spherical object fitted onto the spindle to increase and maintain the speed of the spin. Historically, whorls have been made of materials like amber, antler, bone, ceramic, coral, glass, stone, metal (iron, lead, lead ...
,
Trackball
A trackball is a pointing device consisting of a ball held by a socket containing sensors to detect a rotation of the ball about two axes—like an upside-down ball mouse with an exposed protruding ball. Users roll the ball to position the on-s ...
,
Wagon-wheel effect
The wagon-wheel effect (alternatively called stagecoach-wheel effect or stroboscopic effect) is an optical illusion in which a spoked wheel appears to rotate differently from its true rotation. The wheel can appear to rotate more slowly than the ...
,
Water wheel
A water wheel is a machine for converting the energy of flowing or falling water into useful forms of power, often in a watermill. A water wheel consists of a wheel (usually constructed from wood or metal), with a number of blades or buckets ...
,
Wheelbarrow
A wheelbarrow is a small hand-propelled vehicle, usually with just one wheel, designed to be pushed and guided by a single person using two handles at the rear, or by a sail to push the ancient wheelbarrow by wind. The term "wheelbarrow" is mad ...
,
Wheelie
In vehicle acrobatics, a wheelie, or wheelstand, is a vehicle maneuver in which the front wheel or wheels come off the ground due to sufficient torque being applied to the rear wheel or wheels, or rider motion relative to the vehicle. Whe ...
,
Wheel of Fortune The Wheel of Fortune or ''Rota Fortunae'' has been a concept and metaphor since ancient times referring to the capricious nature of Fate. Wheel of Fortune may also refer to:
Arts, entertainment, and media Art
* ''The Wheel of Fortune'' (Burne-Jo ...
,
Wheelwright
A wheelwright is a craftsman who builds or repairs wooden wheels. The word is the combination of "wheel" and the word "wright", (which comes from the Old English word "''wryhta''", meaning a worker or shaper of wood) as in shipwright and arkw ...
,
Windlass
The windlass is an apparatus for moving heavy weights. Typically, a windlass consists of a horizontal cylinder (barrel), which is rotated by the turn of a crank or belt. A winch is affixed to one or both ends, and a cable or rope is wound arou ...
,
Windmill
A windmill is a structure that converts wind power into rotational energy using vanes called windmill sail, sails or blades, specifically to mill (grinding), mill grain (gristmills), but the term is also extended to windpumps, wind turbines, and ...
* Alternatives:
Air cushion,
Continuous track
Continuous track is a system of vehicle propulsion used in tracked vehicles, running on a continuous band of treads or track plates driven by two or more wheels. The large surface area of the tracks distributes the weight of the vehicle b ...
,
Counter-rotating screws,
Leg mechanism,
Magnetic levitation
Magnetic levitation (maglev) or magnetic suspension is a method by which an object is suspended with no support other than magnetic fields. Magnetic force is used to counteract the effects of the gravitational force and any other forces.
The ...
,
Wing-in-ground-effect
A ground-effect vehicle (GEV), also called a wing-in-ground-effect (WIG), ground-effect craft, wingship, flarecraft or ekranoplan (russian: экранопла́н – "screenglider"), is a vehicle that is able to move over the surface by gainin ...
* History:
History of the wheel in Africa, ''
The Horse, The Wheel and Language
''The Horse, the Wheel, and Language: How Bronze-Age Riders from the Eurasian Steppes Shaped the Modern World'' is a 2007 book by the anthropologist David W. Anthony, in which the author describes his "revised Kurgan theory." He explores the or ...
'',
Rotating locomotion in living systems
Rotation, or spin, is the circular movement of an object around a '' central axis''. A two-dimensional rotating object has only one possible central axis and can rotate in either a clockwise or counterclockwise direction. A three-dimensional ...
,
Terrestrial locomotion in animals: Rolling,
Robot locomotion
Robot locomotion is the collective name for the various methods that robots use to transport themselves from place to place.
Wheeled robots are typically quite energy efficient and simple to control. However, other forms of locomotion may be more ...
* Theory:
Rolling resistance
Rolling resistance, sometimes called rolling friction or rolling drag, is the force resisting the motion when a body (such as a ball, tire, or wheel) rolls on a surface. It is mainly caused by non-elastic effects; that is, not all the energy nee ...
,
Rotational energy
Rotational energy or angular kinetic energy is kinetic energy due to the rotation of an object and is part of its total kinetic energy. Looking at rotational energy separately around an object's axis of rotation, the following dependence on the o ...
,
Torque
In physics and mechanics, torque is the rotational equivalent of linear force. It is also referred to as the moment of force (also abbreviated to moment). It represents the capability of a force to produce change in the rotational motion of th ...
,
Wheel and axle (simple machine),
Wheel sizing
The wheel size for a motor vehicle or similar wheel has a number of parameters.
Units
The millimetre is most commonly used to specify dimensions in modern production, but marketing of wheel sizes towards customers is still sometimes done with tr ...
References
External links
* University of Kiel.
3400 BC: The oldest evidence for the use of the wheel and wagon originates from Northern Germany. Online: April 11th, 2022. Retrieved: April 14th, 2022.
{{Authority control
Iraqi inventions
Mesopotamian inventions