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Outrunner
An outrunner is an electric motor having the rotor outside the stator, as though the motor were turned inside out. They are often used in radio-controlled model aircraft. This type of motor spins its outer shell around its windings, much like motors found in ordinary CD-ROM computer drives. In fact, CD-ROM motors are frequently rewound into brushless outrunner motors for small park flyer aircraft. Parts to aid in converting CD-ROM motors to aircraft use are commercially available. Usually, outrunners have more poles, so they spin much slower than their inrunner counterparts with their more traditional layout (though still considerably faster than ferrite motors, when compared with motors that use neodymium magnets) while producing far more torque. This makes an outrunner an excellent choice for directly driving electric aircraft propellers since they eliminate the extra weight, complexity, inefficiency and noise of a gearbox. Some front loading direct-drive washing machines u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inrunner
The term inrunner refers to an electric motor where the rotor (runner) is inside the stator. The term is in particular used for brushless motors to differentiate them from outrunners that have their rotor outside the stator. The vast majority of electric motors are inrunners. Usage in drones and model aircraft Compared to outrunner motors, inrunners tend to spin exceptionally fast, often as high as 11000 RPM per volt, far too fast for most aircraft propellers. However, inrunners lack torque. As a result, most inrunners are used in conjunction with a gearbox in both surface and aircraft models to reduce speed and increase torque In many cases the inrunner is "ironless" in that there is no iron stator core to magnetize. The wire is run inside the can and held in place by epoxy or other resin material. Because there is no magnetic iron core, ironless in runners have no "cogging", in that they spin freely with no magnetic interaction when power is disconnected. A well-designed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inrunner
The term inrunner refers to an electric motor where the rotor (runner) is inside the stator. The term is in particular used for brushless motors to differentiate them from outrunners that have their rotor outside the stator. The vast majority of electric motors are inrunners. Usage in drones and model aircraft Compared to outrunner motors, inrunners tend to spin exceptionally fast, often as high as 11000 RPM per volt, far too fast for most aircraft propellers. However, inrunners lack torque. As a result, most inrunners are used in conjunction with a gearbox in both surface and aircraft models to reduce speed and increase torque In many cases the inrunner is "ironless" in that there is no iron stator core to magnetize. The wire is run inside the can and held in place by epoxy or other resin material. Because there is no magnetic iron core, ironless in runners have no "cogging", in that they spin freely with no magnetic interaction when power is disconnected. A well-designed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Front Electric Sustainer
Front electric sustainer (FES) is a propulsion system for gliders that uses an electric motor powered by batteries and a foldable propeller. It is produced by LZ Design d.o.o. in Logatec, Slovenia. The system uses a 22 kW compact outrunner brushless DC electric motor located in the nose of the sailplane. Power is provided by two lithium-ion battery packs. Lighter gliders are able to self-launch with FES. Heavier gliders can use it as a sustainer system, i.e. climb and cruise sufficiently high and far to avoid an out-landing. Although gliders with FES have a shorter range (70–100 km) under power than gliders with two-stroke gasoline sustainer engines (10 litres at 8.5 L/h at 100 km/h = 120 km) or jet sustaining engines (150–200 km), the electric motor can be expected to start reliably provided there is sufficient energy in the batteries. The one-metre diameter propeller is made of carbon fibre and folds across the nose. It opens using centrifugal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio-controlled Aircraft
A radio-controlled aircraft (often called RC aircraft or RC plane) is a small flying machine that is controlled remotely by an operator on the ground using a hand-held radio transmitter. The transmitter continuously communicates with a receiver (radio), receiver within the craft that sends signals to servomechanisms (servos) which move the Flight control surfaces, control surfaces based on the position of joysticks on the transmitter. The control surfaces, in turn, directly affect the orientation of the plane. Flying RC aircraft as a hobby grew substantially from the 2000s with improvements in the cost, weight, performance, and capabilities of motors, battery (electricity), batteries and electronics. Scientific, government, and military organizations are also using RC aircraft for experiments, gathering weather readings, aerodynamics, aerodynamic modeling, and testing. A wide variety of models, parts, and styles is available for the DIY market. Nowadays, distinct from recreationa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Control
Radio control (often abbreviated to RC) is the use of control signals transmitted by radio to remotely control a device. Examples of simple radio control systems are garage door openers and keyless entry systems for vehicles, in which a small handheld radio transmitter unlocks or opens doors. Radio control is also used for control of model vehicles from a hand-held radio transmitter. Industrial, military, and scientific research organizations make use of radio-controlled vehicles as well. A rapidly growing application is control of unmanned aerial vehicles (UAVs or drones) for both civilian and military uses, although these have more sophisticated control systems than traditional applications. History The idea of controlling unmanned vehicles (for the most part in an attempt to improve the accuracy of torpedoes for military purposes) predates the invention of radio. The latter half of the 1800s saw development of many such devices, connected to an operator by wires, inclu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Counter-electromotive Force
Counter-electromotive force (counter EMF, CEMF, back EMF),Graf, "counterelectromotive force", Dictionary of Electronics is the electromotive force (EMF) manifesting as a voltage that opposes the change in current which induced it. CEMF is the EMF caused by electromagnetic induction. Details For example, the voltage appearing across an inductor or coil is due to a change in current which causes a change in the magnetic field within the coil, and therefore the self-induced voltage. The polarity of the voltage at every moment opposes that of the change in applied voltage, to keep the current constant. The term ''back electromotive force'' is also commonly used to refer to the voltage that occurs in electric motors where there is relative motion between the armature and the magnetic field produced by the motor's field coils or permanent magnet field, thus also acting as a generator while running as a motor. This effect is not due to the motor's inductance, which generates a volta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cogging Torque
Cogging torque of electrical motors is the torque due to the interaction between the permanent magnets of the rotor and the stator slots of a permanent magnet machine. It is also known as ''detent'' or ''no-current torque''. This torque is position dependent and its periodicity per revolution depends on the number of magnetic poles and the number of teeth on the stator. Cogging torque is an undesirable component for the operation of such a motor. It is especially prominent at lower speeds, with the symptom of jerkiness. Cogging torque results in torque as well as speed ripple; however, at high speed the motor moment of inertia filters out the effect of cogging torque. Reducing the cogging torque A summary of techniques used for reducing cogging torque: * Skewing stator stack or magnets * Using fractional slots per pole * Optimizing the magnet pole arc or width Almost all the techniques used against cogging torque also reduce the motor counter-electromotive force and so reduce the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slovenia
Slovenia ( ; sl, Slovenija ), officially the Republic of Slovenia (Slovene: , abbr.: ''RS''), is a country in Central Europe. It is bordered by Italy to the west, Austria to the north, Hungary to the northeast, Croatia to the southeast, and the Adriatic Sea to the southwest. Slovenia is mostly mountainous and forested, covers , and has a population of 2.1 million (2,108,708 people). Slovenes constitute over 80% of the country's population. Slovene, a South Slavic language, is the official language. Slovenia has a predominantly temperate continental climate, with the exception of the Slovene Littoral and the Julian Alps. A sub-mediterranean climate reaches to the northern extensions of the Dinaric Alps that traverse the country in a northwest–southeast direction. The Julian Alps in the northwest have an alpine climate. Toward the northeastern Pannonian Basin, a continental climate is more pronounced. Ljubljana, the capital and largest city of Slovenia, is geogr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 a working fluid such as water or air. Propellers are used to pump fluid through a pipe or duct, or to create thrust to propel a boat through water or an aircraft through air. The blades are specially shaped so that their rotational motion through the fluid causes a pressure difference between the two surfaces of the blade by Bernoulli's principle which exerts force on the fluid. Most marine propellers are screw propellers with helical blades rotating on a propeller shaft (ship), propeller shaft with an approximately horizontal axis. History Early developments The principle employed in using a screw propeller is derived from sculling. In sculling, a single blade is moved through an arc, from side to side taking care to keep presenting the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glider (aircraft)
A glider is a fixed-wing aircraft that is supported in flight by the dynamic reaction of the air against its lifting surfaces, and whose free flight does not depend on an engine. Most gliders do not have an engine, although motor-gliders have small engines for extending their flight when necessary by sustaining the altitude (normally a sailplane relies on rising air to maintain altitude) with some being powerful enough to take off by self-launch. There are a wide variety of types differing in the construction of their wings, aerodynamic efficiency, location of the pilot, controls and intended purpose. Most exploit meteorological phenomena to maintain or gain height. Gliders are principally used for the air sports of gliding, hang gliding and paragliding. However some spacecraft have been designed to descend as gliders and in the past military gliders have been used in warfare. Some simple and familiar types of glider are toys such as paper planes and balsa wood gliders. Etym ... [...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] |
_with_front-end_electric_sustainer_(FES).jpg "Click for more on -> Front Electric Sustainer")
