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Electric Carriage
Practical electric vehicles appeared during the 1890s. An electric vehicle held the vehicular land speed record until around 1900. In the 20th century, the high cost, low top speed, and short-range of battery electric vehicles, compared to internal combustion engine vehicles, led to a worldwide decline in their use as private motor vehicles. Electric vehicles have continued to be used for loading and freight equipment and for public transport – especially rail vehicles. At the beginning of the 21st century, interest in electric and alternative fuel vehicles in private motor vehicles increased due to: growing concern over the problems associated with hydrocarbon-fueled vehicles, including damage to the environment caused by their emissions; the sustainability of the current hydrocarbon-based transportation infrastructure; and improvements in electric vehicle technology. Since 2010, combined sales of all-electric cars and utility vans achieved 1 million units delivered g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hybrid Electric Vehicle
A hybrid electric vehicle (HEV) is a type of hybrid vehicle that combines a conventional internal combustion engine (ICE) system with an electric propulsion system ( hybrid vehicle drivetrain). The presence of the electric powertrain is intended to achieve either better fuel economy than a conventional vehicle or better performance. There is a variety of HEV types and the degree to which each function as an electric vehicle (EV) also varies. The most common form of HEV is the hybrid electric car, although hybrid electric trucks (pickups and tractors), buses, boats and aircraft also exist. Modern HEVs make use of efficiency-improving technologies such as regenerative brakes which convert the vehicle's kinetic energy to electric energy, which is stored in a battery or supercapacitor. Some varieties of HEV use an internal combustion engine to turn an electrical generator, which either recharges the vehicle's batteries or directly powers its electric drive motors; this combinatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electric Motor
An electric motor is an Electric machine, electrical machine that converts electrical energy into mechanical energy. Most electric motors operate through the interaction between the motor's magnetic field and electric current in a Electromagnetic coil, wire winding to generate force in the form of torque applied on the motor's shaft. An electric generator is mechanically identical to an electric motor, but operates with a reversed flow of power, converting mechanical energy into electrical energy. Electric motors can be powered by direct current (DC) sources, such as from batteries, or rectifiers, or by alternating current (AC) sources, such as a power grid, Inverter (electrical), inverters or electrical generators. Electric motors may be classified by considerations such as power source type, construction, application and type of motion output. They can be powered by AC or DC, be Brushed motor, brushed or Brushless motor, brushless, single-phase, Two-phase electric power, two-p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commutator (electric)
A commutator is a rotary electrical switch in certain types of electric motors and electrical generators that periodically reverses the current direction between the rotor and the external circuit. It consists of a cylinder composed of multiple metal contact segments on the rotating armature of the machine. Two or more electrical contacts called " brushes" made of a soft conductive material like carbon press against the commutator, making sliding contact with successive segments of the commutator as it rotates. The windings (coils of wire) on the armature are connected to the commutator segments. Commutators are used in direct current (DC) machines: dynamos (DC generators) and many DC motors as well as universal motors. In a motor the commutator applies electric current to the windings. By reversing the current direction in the rotating windings each half turn, a steady rotating force (torque) is produced. In a generator the commutator picks off the current generated in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reluctance Motor
A reluctance motor is a type of electric motor that induces non-permanent magnetic poles on the ferromagnetic rotor. The rotor does not have any windings. It generates torque through magnetic reluctance. Reluctance motor subtypes include synchronous, variable, Switched reluctance motor, switched and variable stepping. Reluctance motors can deliver high power density at low cost, making them attractive for many applications. Disadvantages include high torque ripple (the difference between maximum and minimum torque during one revolution) when operated at low speed, and noise due to torque ripple. Until the early twenty-first century, their use was limited by the complexity of designing and controlling them. Advances in theory, computer design tools, and low-cost embedded systems for control overcame these obstacles. Microcontrollers use real-time computing control algorithms to tailor drive waveforms according to rotor position and current/voltage feedback. Before the development ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Direct-drive
A direct-drive mechanism is a mechanism design where the force or torque from a prime mover is transmitted directly to the effector device (such as the drive wheels of a vehicle) without involving any intermediate couplings such as a gear train or a belt.Asada, H., & Kanade, T. (1983) Design of direct-drive mechanical arms' in ''Journal of Vibration, Acoustics, Stress, and Reliability in Design'', Volume 105, Issue 3, pp.312-316 History In the late 19th century and early 20th century, some of the earliest locomotives and cars used direct drive transmissions at higher speeds. Direct-drive mechanisms for industrial arms began to be possible in the 1980s, with the use of rare-earth magnetic materials. The first direct-drive arm was built in 1981 at Carnegie Mellon University. Today the most commonly used magnets are neodymium magnets. Design Direct-drive systems are characterized by smooth torque transmission, and nearly-zero backlash.Bruno Siciliano, Oussama Khatib (Eds., 2008) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Scottish Society Of Arts
The Royal Scottish Society of Arts is a learned society in Scotland, dedicated to the study of science and technology. It was founded as The Society for the Encouragement of the Useful Arts in Scotland by David Brewster, Sir David Brewster in 1821 and dedicated to ''"the promotion of invention and Entrepreneur, enterprise"''. The Society was granted a Royal Charter in 1841. Background For many years the promotion of invention and improvements of all sorts was the main business of the Society, and its meetings were the focus of a large and active cross-section of Edinburgh society - academics, gentry, professionals such as civil engineers and lawyers, and skilled craftsmen such as instrument makers, engravers and printers. The Society's published Transactions provide a record of changes in technology, and the Society's archive is held by the National Library of Scotland, and is a valuable resource to researchers. In more recent times, the Society's meeting programme has been bas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galvanic Cell
A galvanic cell or voltaic cell, named after the scientists Luigi Galvani and Alessandro Volta, respectively, is an electrochemical cell in which an electric current is generated from spontaneous Oxidation-Reduction reactions. A common apparatus generally consists of two different metals, each immersed in separate beakers containing their respective metal ions in solution that are connected by a salt bridge or separated by a porous membrane. Volta was the inventor of the voltaic pile, the first Battery (electricity), electrical battery. In common usage, the word "battery" has come to include a single galvanic cell, but a battery properly consists of multiple cells. History In 1780, Luigi Galvani discovered that when two different metals (e.g., copper and zinc) are in contact and then both are touched at the same time to two different parts of a muscle of a frog leg, to close the circuit, the frog's leg contracts. He called this "bioelectricity, animal electricity". The frog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aberdeen
Aberdeen (; sco, Aiberdeen ; gd, Obar Dheathain ; la, Aberdonia) is a city in North East Scotland, and is the third most populous city in the country. Aberdeen is one of Scotland's 32 local government council areas (as Aberdeen City), and has a population estimate of for the city of Aberdeen, and for the local council area making it the United Kingdom's 39th most populous built-up area. The city is northeast of Edinburgh and north of London, and is the northernmost major city in the United Kingdom. Aberdeen has a long, sandy coastline and features an oceanic climate, with cool summers and mild, rainy winters. During the mid-18th to mid-20th centuries, Aberdeen's buildings incorporated locally quarried grey granite, which may sparkle like silver because of its high mica content. Since the discovery of North Sea oil in 1969, Aberdeen has been known as the offshore oil capital of Europe. Based upon the discovery of prehistoric villages around the mouths of the rivers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert Davidson (inventor)
Robert Davidson (1804–1894) was a Scottish inventor who built the first known electric locomotive in 1837. He was a lifelong resident of Aberdeen, northeast Scotland, where he was a prosperous chemist and dyer, amongst other ventures. Davidson was educated at Marischal College, where he studied second and third year classes from 1819-1821, including lectures from Professor Patrick Copland. He got this education in return for being a lab assistant. In the 1820s, he set up in business close to the Aberdeen-Inverurie Canal, at first supplying yeast, before becoming involved in the manufacture and supply of chemicals. He became interested in the new electrical technologies of the day. From 1837, he made small electric motors on his own principles. Exhibitions Davidson staged an exhibition of electrical machinery at Aberdeen, Scotland, and in Edinburgh where it was viewed on February 12, 1842, by the young James Clerk Maxwell. Later he exhibited at the Egyptian Hall in Piccadi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Davenport (inventor)
Thomas Davenport (July 9, 1802 – July 6, 1851) was a Vermont blacksmith who constructed the first American DC electric motor in 1834. Biography Davenport was born in Williamstown, Vermont. He lived in Forest Dale, a village near the town of Brandon. As early as 1834, he developed a battery-powered electric motor. He used it to operate a small model car on a short section of track, paving the way for the later electrification of streetcars. Davenport's 1833 visit to the Penfield and Taft iron works at Crown Point, New York, where an electromagnet was operating, based on the design of Joseph Henry, was an impetus for his electromagnetic undertakings. Davenport bought an electromagnet from the Crown Point factory and took it apart to see how it worked. Then he forged a better iron core and redid the wiring, using silk from his wife's wedding gown. With his wife Emily and colleague Orange Smalley, Davenport received the first American patent on an electric machine in 1837 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blacksmith
A blacksmith is a metalsmith who creates objects primarily from wrought iron or steel, but sometimes from #Other metals, other metals, by forging the metal, using tools to hammer, bend, and cut (cf. tinsmith). Blacksmiths produce objects such as gates, grilles, railings, light fixtures, furniture, sculpture, tools, agricultural implements, decorative and religious items, cooking utensils, and weapons. There was an historical distinction between the heavy work of the blacksmith and the more delicate operation of a whitesmith, who usually worked in Goldsmith, gold, Silversmith, silver, pewter, or the finishing steps of fine steel. The place where a blacksmith works is called variously a smithy, a forge or a blacksmith's shop. While there are many people who work with metal such as farriers, wheelwrights, and Armourer, armorers, in former times the blacksmith had a general knowledge of how to make and repair many things, from the most complex of weapons and armor to simple things ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vermont
Vermont () is a state in the northeast New England region of the United States. Vermont is bordered by the states of Massachusetts to the south, New Hampshire to the east, and New York to the west, and the Canadian province of Quebec to the north. Admitted to the union in 1791 as the 14th state, it is the only state in New England not bordered by the Atlantic Ocean. According to the 2020 U.S. census, the state has a population of 643,503, ranking it the second least-populated in the U.S. after Wyoming. It is also the nation's sixth-smallest state in area. The state's capital Montpelier is the least-populous state capital in the U.S., while its most-populous city, Burlington, is the least-populous to be a state's largest. For some 12,000 years, indigenous peoples have inhabited this area. The competitive tribes of the Algonquian-speaking Abenaki and Iroquoian-speaking Mohawk were active in the area at the time of European encounter. During the 17th century, Fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
