|
Quadcopter
A quadcopter, also called quadrocopter, or quadrotor is a type of helicopter or multicopter that has four rotors. Although quadrotor helicopters and convertiplanes have long been flown experimentally, the configuration remained a curiosity until the arrival of the modern unmanned aerial vehicle or drone. The small size and low inertia of drones allows use of a particularly simple flight control system, which has greatly increased the practicality of the small quadrotor in this application. Design principles Each rotor produces both lift and torque about its center of rotation, as well as drag opposite to the vehicle's direction of flight. Quadcopters generally have two rotors spinning clockwise (CW) and two counterclockwise (CCW). Flight control is provided by independent variation of the speed and hence lift and torque of each rotor. Pitch and roll are controlled by varying the net centre of thrust, with yaw controlled by varying the net torque. Unlike conventional hel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadcopter Camera Drone In Flight
A quadcopter, also called quadrocopter, or quadrotor is a type of helicopter or multicopter that has four Helicopter rotor, rotors. Although quadrotor helicopters and convertiplanes have long been flown experimentally, the configuration remained a curiosity until the arrival of the modern unmanned aerial vehicle or drone. The small size and low inertia of drones allows use of a particularly simple flight control system, which has greatly increased the practicality of the small quadrotor in this application. Design principles Each rotor produces both lift (force), lift and torque about its center of rotation, as well as drag force, drag opposite to the vehicle's direction of flight. Quadcopters generally have two rotors spinning clockwise (CW) and two counterclockwise (CCW). Flight control is provided by independent variation of the speed and hence lift and torque of each rotor. Pitch and roll are controlled by varying the net centre of thrust, with yaw controlled by varying t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unmanned Aerial Vehicle
An unmanned aerial vehicle (UAV) or unmanned aircraft system (UAS), commonly known as a drone, is an aircraft with no human pilot, crew, or passengers onboard, but rather is controlled remotely or is autonomous.De Gruyter Handbook of Drone Warfare; 2024. e-ISBN (PDF) 978-3-11-074203-9.H. Pan; M. Zahmatkesh; F. Rekabi-Bana; F. Arvin; J. HuT-STAR: Time-Optimal Swarm Trajectory Planning for Quadrotor Unmanned Aerial Vehicles IEEE Transactions on Intelligent Transportation Systems, 2025. UAVs were originally developed through the twentieth century for military missions too "dull, dirty or dangerous" for humans, and by the twenty-first, they had become essential assets to most militaries. As control technologies improved and costs fell, their use expanded to many non-military applications. These include aerial photography, area coverage,F. Rekabi-Bana; Hu, J.; T. Krajník; Arvin, F.,Unified Robust Path Planning and Optimal Trajectory Generation for Efficient 3D Area Coverage of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helicopter
A helicopter is a type of rotorcraft in which Lift (force), lift and thrust are supplied by horizontally spinning Helicopter rotor, rotors. This allows the helicopter to VTOL, take off and land vertically, to hover (helicopter), hover, and to fly forward, backward and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft and many forms of short take-off and landing (STOL) or short take-off and vertical landing (STOVL) aircraft cannot perform without a runway. The Focke-Wulf Fw 61 was the first successful, practical, and fully controllable helicopter in 1936, while in 1942, the Sikorsky R-4 became the first helicopter to reach full-scale mass production, production. Starting in 1939 and through 1943, Igor Sikorsky worked on the development of the Vought-Sikorsky VS-300, VS-300, which over four iterations, became the basis for modern helicopters with a single main rotor and a single tail rotor. Although most earlier ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multicopter
A multirotor or multicopter is a rotorcraft with more than two lift (force), lift-generating helicopter rotor, rotors. An advantage of multirotor aircraft is the simpler rotor mechanics required for flight control. Unlike single- and double-rotor helicopters which use complex variable pitch rotors whose pitch varies as the blade rotates for flight stability and control, multirotors often use fixed-Blade pitch, pitch blades; control of vehicle motion is achieved by varying the relative speed of each rotor to change the thrust and torque produced by each. Due to their ease of both construction and control, multirotor aircraft are frequently used in Radio-controlled aircraft, radio control aircraft and Unmanned aerial vehicle, unmanned aerial vehicle (UAV) (drone) projects in which the names tricopter, quadcopter, hexacopter and octocopter are frequently used to refer to 3-, 4-, 6- and 8-rotor rotorcraft, respectively. There is also the X8 (also called ''octo-quad'') configuration ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helicopter Rotor
On a helicopter, the main rotor or rotor system is the combination of several rotary wings (rotor blades) with a control system, that generates the aerodynamic lift (force), lift force that supports the weight of the helicopter, and the thrust that counteracts aerodynamic drag in forward flight. Each main rotor is mounted on a vertical mast over the top of the helicopter, as opposed to a helicopter tail rotor, which connects through a combination of drive shaft(s) and gearboxes along the tail boom. The blade pitch is typically controlled by the pilot using the helicopter flight controls. Helicopters are one example of rotary-wing aircraft (rotorcraft). The name is derived from the Greek words ''helix'', helik-, meaning spiral; and ''pteron'' meaning wing. Design principles Overview The helicopter rotor is powered by the engine, through the transmission, to the rotating mast. The mast is a cylindrical metal shaft that extends upward from—and is driven by—the transmission. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multirotor
A multirotor or multicopter is a rotorcraft with more than two lift-generating rotors. An advantage of multirotor aircraft is the simpler rotor mechanics required for flight control. Unlike single- and double-rotor helicopters which use complex variable pitch rotors whose pitch varies as the blade rotates for flight stability and control, multirotors often use fixed- pitch blades; control of vehicle motion is achieved by varying the relative speed of each rotor to change the thrust and torque produced by each. Due to their ease of both construction and control, multirotor aircraft are frequently used in radio control aircraft and unmanned aerial vehicle (UAV) (drone) projects in which the names tricopter, quadcopter, hexacopter and octocopter are frequently used to refer to 3-, 4-, 6- and 8-rotor rotorcraft, respectively. There is also the X8 (also called ''octo-quad'') configuration that is similar to the quadracopter design, except that it has eight rotors; the lower of wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coaxial Rotors
A coaxial-rotor aircraft is an aircraft whose helicopter rotor, rotors are mounted one above the other on Concentric objects, concentric shafts, with the same axis of rotation, but turning in opposite directions (contra-rotating). This rotor configuration is a feature of helicopters produced by the Russian Kamov helicopter design bureau. History The idea of coaxial rotors originates with Mikhail Lomonosov. He had developed a small helicopter model with coaxial rotors in July 1754 and demonstrated it to the Russian Academy of Sciences. In 1859, the British Patent Office awarded the first helicopter patent to Henry Bright for his coaxial design. From this point, coaxial helicopters developed into fully operational machines as we know them today. Two pioneering helicopters, the Corradino D'Ascanio#Between the wars, Corradino D'Ascanio-built "D'AT3" of 1930, and the generally more successful French mid-1930s ''Gyroplane Laboratoire'', both used coaxial rotor systems for flight. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
De Bothezat Helicopter
The de Bothezat helicopter, also known as the Jerome-de Bothezat Flying Octopus, was an experimental quadrotor helicopter built for the United States Army Air Service by George de Bothezat in the early 1920s, and was said at the time to be the first successful helicopter. Although its four massive six-bladed rotors allowed the craft to fly successfully, it suffered from complexity, control difficulties, and high pilot workload, and was reportedly only capable of forward flight in a favorable wind. The Army canceled the program in 1924, and the aircraft was scrapped. Development and testing Self-described as "the world's greatest scientist and outstanding mathematician",Young 1982, p. 36. and having written one of the first scientific papers on the aerodynamics of rotary-wing flight, George de Bothezat was a refugee from the Russian Empire who had fled to the United States in the wake of the Russian Revolution. Having written and lectured extensively on rotorcraft theory, d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
George De Bothezat
George de Bothezat (, ; 7 June 1882 – 1 February 1940) was a Romanian-Russian American engineer, businessman, and pioneer of helicopter flight. Biography George de Bothezat was born in 1882 in Saint Petersburg, Russian Empire, to Alexander Botezat and Nadine Rabutowskaja.Gheorghe Botezatu at The National Library of Moldova His father Alexander Il'ich Botezat belonged to a family of n landlords, graduated from the department of history and philology of the Saint Petersburg University and worked in the [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VTOL
A vertical take-off and landing (VTOL) aircraft is one that can takeoff and landing, take off and land vertically without relying on a runway. This classification can include a variety of types of aircraft including helicopters as well as thrust-vectoring fixed-wing aircraft and other hybrid aircraft with powered helicopter rotor, rotors such as cyclogyro, cyclogyros/cyclocopters and gyrodynes. Some VTOL aircraft can operate in other modes as well, such as CTOL (conventional take-off & landing), STOL (short take-off & landing), or STOVL (short take-off & vertical landing). Others, such as some helicopters, can only operate as VTOL, due to the aircraft lacking landing gear that can handle taxiing. VTOL is a subset of V/STOL (vertical or short take-off & landing). Some aerostat, lighter-than-air aircraft also qualify as VTOL aircraft, as they can hover, takeoff and land with vertical approach/departure profiles. Electric vertical takeoff and landing aircraft, or eVTOLs, are being ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
