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plane, stabilized the machine laterally. Another propeller was mounted at the nose for steering. The remaining pair of propellers functioned as its forward propulsion. The aircraft exhibited a considerable degree of stability and increase in control-accuracy for its time, and made over a thousand test flights during the middle 1920s. By 1923 it was able to remain airborne for several minutes at a time, and on April 14, 1924, it established the first-ever FAI distance record for helicopters of 360 m (390 yd). It demonstrated the ability to complete a circular course and later, it completed the first 1 kilometre (0.62 mi) closed-circuit flight by a rotorcraft.
392:
helicopter proved the quadrotor design and it was also the first four-rotor helicopter to demonstrate successful forward flight. Due to a lack of orders for commercial or military versions however, the project was terminated. Convertawings proposed a Model E that would have a maximum weight of 42,000 lb (19 t) with a payload of 10,900 lb (4.9 t) over 300 miles and at up to 173 mph (278 km/h). The Hanson
Elastic Articulated (EA) bearingless rotor grew out of work done in the early 1960s at Lockheed California by Thomas F. Hanson, who had previously worked at Convertawings on the quadrotor's rotor design and control system.
193:
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vehicles safer for close interaction. It is also possible to fit quadcopters with guards that enclose the rotors, further reducing the potential for damage. However, as size increases, fixed propeller quadcopters develop disadvantages relative to conventional helicopters. Increasing blade size increases their momentum. This means that changes in blade speed take longer, which negatively impacts control. Helicopters do not experience this problem as increasing the size of the rotor disk does not significantly impact the ability to control blade pitch.
234:
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379:, it made its first flight in October 1922. About 100 flights were made by the end of 1923. The highest it ever reached was about 5 m (16 ft 5 in). Although demonstrating feasibility, it was underpowered, unresponsive, mechanically complex and susceptible to reliability problems. Pilot workload was too high during hover to attempt lateral motion.
52:
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or drones. The need for aircraft with greater maneuverability and hovering ability has led to a rise in quadcopter research. The four-rotor design allows quadcopters to be relatively simple in design yet highly reliable and maneuverable. Research is continuing to increase the abilities of quadcopters
399:
Crop
Sprayer project of 1960 was an early example of a quadcopter drone. To be powered by a 105 hp Potez 4E air-cooled flat four-cylinder engine, its 20 gal payload was discharged through a 22 ft spray boom. Two operators carried homing beacons at opposite ends of the spray run, so that the
353:
experimented with rotorcraft designs in the 1920s. Among the designs he tried was the
Oehmichen No. 2, which employed four two-blade rotors and eight propellers, all driven by a single engine. The angle of the rotor blades could be varied by warping. Five of the propellers, spinning in the horizontal
404:
528:
For small drones, quadcopters are cheaper and more durable than conventional helicopters due to their mechanical simplicity. Their smaller blades are also advantageous because they possess less kinetic energy, reducing their ability to cause damage. For small-scale quadcopters, this makes the
391:
was intended to be the prototype for a line of much larger civil and military helicopters. The design featured two engines driving four rotors through a system of v belts. No tail rotor was needed and control was obtained by varying the thrust between rotors. Flown many times from 1956, this
321:
The longest flight time achieved by a battery-powered quadcopter was 2 hours, 31 minutes and 30 seconds. The record was set by
Ferdinand Kickinger of Germany in 2016. In setting the record, Kickinger used low discharge-rate, high-capacity lithium-ion batteries and stripped the airframe of
548:
wall, some drug cartels have resorted to the use of quadcopters to smuggle drugs. However, quadcopter drones do not necessarily only smuggle drugs across the border, but there are also cases where weapons and other prohibited items are smuggled into prisons around the world.
165:, which generates no useful lift) can be eliminated by counter-rotation, and the relatively short blades are much easier to construct. A number of manned designs appeared in the 1920s and 1930s. These vehicles were among the first successful heavier-than-air
494:
by making advances in multi-craft communication, environment exploration, and maneuverability. If these developing qualities can be combined, quadcopters would be capable of advanced autonomous missions that are currently not possible with other vehicles.
400:
quadcopter would always home in on a beacon and not overshoot. However, despite the much simplified design and operational requirements compared to a piloted machine, the parent company board refused to develop it and it remained a paper project.
185:
is zero, which means there is no need for a tail rotor as on conventional helicopters. Yaw is induced by mismatching the balance in aerodynamic torques (i.e., by offsetting the cumulative thrust commands between the counter-rotating blade pairs).
152:
Unlike conventional helicopters, quadcopters do not usually have cyclic pitch control, in which the angle of the blades varies dynamically as they turn around the rotor hub. In the early days of flight, quadcopters (then referred to either as
730:
233:
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Alternative power sources like hydrogen fuel cells and hybrid gas-electric generators have been used to dramatically extend endurance because of the increased energy density of both hydrogen and gasoline, respectively.
198:
Schematic of reaction torques on each motor of a quadcopter aircraft, due to spinning rotors. Rotors 1 and 3 spin in one direction, while rotors 2 and 4 spin in the opposite direction, yielding opposing torques for
497:
While small toy remote-controlled quadcopters were produced in Japan already in the early 1990s, the first one with a camera to be produced in significant quantities (Draganflyer
Stabilized Aerial Video System,
375:, with six-bladed rotors at the end of an X-shaped structure. Two small propellers with variable pitch were used for thrust and yaw control. The vehicle used collective pitch control. Built by the
313:
The quadcopter configuration is relatively simple to program for autonomous flight. This has allowed experiments with complex swarming behaviour based on basic sensing of the adjacent drones.
169:
vehicles. However, early prototypes suffered from poor performance, and latter prototypes required too much pilot work load, due to poor stability augmentation and limited control authority.
601:
Hoffmann, G.M.; Rajnarayan, D.G.; Waslander, S.L.; Dostal, D.; Jang, J.S.; Tomlin, C.J. (November 2004). "The
Stanford Testbed of Autonomous Rotorcraft for Multi Agent Control (STARMAC)".
205:
217:
161:) were seen as a possible solution to some of the persistent problems in vertical flight. Torque-induced control issues (as well as efficiency issues originating from the
703:
423:
in competition for the U.S. Army
Transport and Research Command "flying jeep". The VZ-7 was controlled by changing the thrust of each of the four ducted fan rotors.
141:(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
347:. It was tested only in tethered flight and to an altitude of a few feet. In 1908 it was reported as having flown 'several times', although details are sparse.
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110:
of drones allows use of a particularly simple flight control system, which has greatly increased the practicality of the small quadrotor in this application.
239:
A quadrotor adjusts its pitch or roll by applying more thrust to one rotor (or two adjacent rotors) and less thrust to the diametrically opposite rotor.
544:
Throughout the 21st century, there have been reported cases of quadcopter drones being used for criminal activity. Due to the construction of the
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concept takes the fixed quadcopter concept further by combining it with the tilt rotor concept for a proposed C-130 sized military transport.
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was a proposal for a large hybrid aircraft in which four helicopter fuselages were combined with a lighter-than-air airship in the 1980s.
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is developing a battery-powered quadcopter to act as an urban air taxi, at first with a pilot but potentially autonomous in the future.
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or variable-pitch), and motors. For best performance and simplest control algorithms, the motors and propellers are equidistant.
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configuration. In this case, each arm has two motors running in opposite directions (one facing up and one facing down).
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Around 2005 to 2010, advances in electronics allowed the production of cheap lightweight flight controllers,
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have long been flown experimentally, the configuration remained a curiosity until the arrival of the modern
44:
606:
525:. With their small size and maneuverability, these quadcopters can be flown indoors as well as outdoors.
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Quadcopter drone crime is also occurring in Europe. In August 2021, a police officer in the
489:
In the first decades of the 2000s, the quadcopter layout has become popular for small-scale
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92:
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In order to allow more power and stability at reduced weight, a quadcopter, like any other
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A quadrotor hovers or adjusts its altitude by applying equal thrust to all four rotors.
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and cameras. This resulted in the quadcopter configuration becoming popular for small
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40:
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Due to their ease of construction and control, quadcopters are popular as amateur
445:
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181:, with two rotating clockwise and two counterclockwise, the net torque about the
266:
88:
1282:"StrážnĂk v Doksech rukama chytil neregistrovanĂ˝ dron, kterĂ˝ pĹ™enášel pervitin"
974:
820:
620:
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All quadcopters are subject to normal rotorcraft aerodynamics, including the
1164:
In the
Proceedings of the Australasian Conference on Robotics and Automation
286:
134:
656:
In the
Conference of the American Institute of Aeronautics and Astronautics
647:
Hoffman, G.; Huang, H.; Waslander, S.L.; Tomlin, C.J. (20–23 August 2007).
17:
1326:
51:
649:"Quadrotor Helicopter Flight Dynamics and Control: Theory and Experiment"
499:
752:
1254:
107:
1002:
The
Seventh International Conference on Vibration Problems ICOVP 2005
467:
146:
123:
1332:
TED Raffaello D'Andrea: The astounding athletic power of quadcopters
868:
US Manufacturer Harris Aerial Launches New Hybrid Gas Electric Drone
1208:"FrontPage - UAVP-NG - The Open Source Next Generation Multicopter"
1207:
1108:
477:
455:
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402:
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50:
31:
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In the Proceedings of the 23rd Digital Avionics System Conference
261:
The main mechanical components are a fuselage or frame, the four
416:
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non-essential weight to reduce power draw and extend endurance.
166:
403:
343:
to take off vertically was a four-rotor helicopter designed by
227:
by applying more thrust to rotors rotating in one direction.
1047:"Airbus on track to fly its electric aerial taxi in 2018"
556:
seized a quadcopter that was transporting a sachet of
1229:"Drug smugglers turn to drones, advancing operations"
285: – OnyxStar FOX-C8 XT Observer from
1327:
FAA UAS Model Aircraft Operations safety guidelines
1155:Pounds, P.; Mahony, R.; Corke, P. (December 2006).
731:"Historical Overview of V/STOL Aircraft Technology"
642:
640:
133:Quadcopters generally have two rotors spinning
130:opposite to the vehicle's direction of flight.
1157:"Modelling and Control of a Quad-Rotor Robot"
658:. Hilton Head, South Carolina. Archived from
8:
999:Inan, Esin; Kiris, Ahmet (20 January 2007).
975:"Patent US3261407 - Helicopter rotor system"
708:. New York, NY: Cambridge University Press.
697:
695:
605:. Salt Lake City, UT. pp. 12.E.4/1–10.
177:If all four rotors are spinning at the same
678:"How a Quadcopter works | Clay Allen"
485:"whoop" drones can be as light as 30 grams
1061:"Illumin - The Quadrotor's Coming of Age"
610:
145:, with yaw controlled by varying the net
126:about its center of rotation, as well as
596:
594:
1178:"How-To: Quadrocopter based on Arduino"
590:
188:
916:
906:
829:from the original on 22 December 2021
819:Ferdinand Kickinger (30 April 2016),
705:Principles of Helicopter Aerodynamics
7:
889:. Chicago: Time-Life Books. p.
502:Draganflyer I, by Canadian start-up
167:vertical take off and landing (VTOL)
98:Although quadrotor helicopters and
25:
1322:ETH Zurich Research on Quadrotors
934:"A Successful French Helicopter"
680:. University of Alaska, Fairbanks
106:or drone. The small size and low
1280:PokornĂ˝, Petr (10 August 2021).
866:McNabb, Miriam (February 2018).
232:
216:
204:
191:
1083:"A Brief History of Quadrotors"
735:NASA Technical Memorandum 81280
676:Stafford, Jesse (Spring 2014).
506:) was not designed until 1999.
389:Convertawings Model A Quadrotor
950:"1956 - 1564 - Flight Archive"
377:United States Army Air Service
371:and Ivan Jerome developed the
1:
799:"Wyvern Quadrotor Helicopter"
1101:"Our Story | Draganfly"
1034:Gloster Aircraft Since 1917
546:Mexico–United States border
339:The first heavier-than-air
27:Helicopter with four rotors
1363:
463:2.0 take-off, Nevada, 2012
440:Bell Boeing Quad TiltRotor
883:Young, Warren R. (1982).
822:151min30s FPV with Copter
621:10.1109/DASC.2004.1390847
519:global positioning system
118:Each rotor produces both
1166:. Auckland, New Zealand.
1132:Fascination Quadrocopter
1087:Air & Space Magazine
575:Human-powered helicopter
523:unmanned aerial vehicles
491:unmanned aerial vehicles
449:Flying prototype of the
223:A quadrotor adjusts its
797:Uriah (13 April 2010).
729:Anderson, S.B. (1997).
702:Leishman, J.G. (2000).
104:unmanned aerial vehicle
1310:UPenn GRASP Laboratory
1130:BĂĽchi, Roland (2011).
1036:, Putnam, 1971, p.413.
486:
464:
453:
408:
373:de Bothezat helicopter
369:Dr. George de Bothezat
365:
362:de Bothezat helicopter
289:
68:
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1255:"Věznice | EAGLE.ONE"
853:6 August 2020 at the
481:
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419:aircraft designed by
406:
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280:
54:
35:
500:retrospectively also
434:Current developments
257:Mechanical structure
1188:on 11 December 2011
1134:. Books on Demand.
1111:on 12 December 2016
939:24 January 1924 p47
848:How Quadcopters Fly
755:on 27 December 2014
413:Curtiss-Wright VZ-7
407:Curtiss-Wright VZ-7
1315:2015-04-20 at the
1235:. 21 December 2020
776:"Quadcopters: Yaw"
665:on 13 August 2010.
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409:
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290:
69:
49:
1286:ÄŚeskolipskĂ˝ denĂk
1141:978-3-8423-6731-9
1049:. 5 October 2017.
1032:James, Derek N.;
900:978-0-8094-3350-6
540:Criminal activity
351:Etienne Oehmichen
309:Autonomous flight
251:vortex ring state
245:Vortex ring state
114:Design principles
57:racing quadcopter
16:(Redirected from
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139:counterclockwise
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778:. hoverbear.org
774:Andrew Hobden.
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1290:. Retrieved
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1211:. Retrieved
1202:
1190:. Retrieved
1186:the original
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1125:
1113:. Retrieved
1109:the original
1104:
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1081:Darack, Ed.
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1005:. Springer.
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846:SPK Drones.
842:
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753:the original
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1347:Quadcopters
1213:29 December
1192:29 December
1115:17 December
1066:29 December
917:|work=
804:29 December
759:29 December
749:"Quadrotor"
383:Postwar era
281:Quadcopter
159:helicopters
89:multicopter
43:quadcopter
18:Quadcopters
1288:(in Czech)
1261:(in Czech)
979:google.com
684:20 January
586:References
536:projects.
304:Operations
294:multirotor
163:tail rotor
155:quadrotors
85:helicopter
73:quadcopter
63:frame and
1292:10 August
1265:10 August
1259:Eagle.One
1239:10 August
919:ignored (
909:cite book
872:Dronelife
833:26 August
607:CiteSeerX
504:Draganfly
317:Endurance
287:AltiGator
135:clockwise
81:quadrotor
47:in flight
1341:Category
1313:Archived
1018:13 March
984:13 March
959:13 March
851:Archived
827:archived
564:See also
341:aerodyne
335:Pioneers
199:control.
183:yaw axis
55:Typical
1233:DroneDJ
782:3 April
397:Gloster
330:History
283:coaxial
108:inertia
41:Phantom
1138:
1009:
937:Flight
897:
712:
627:
609:
474:Drones
468:Airbus
263:rotors
173:Torque
147:torque
124:torque
93:rotors
67:camera
1160:(PDF)
663:(PDF)
652:(PDF)
267:pitch
79:, or
59:with
45:drone
1294:2021
1267:2021
1241:2021
1215:2014
1194:2014
1182:MAKE
1136:ISBN
1117:2021
1068:2014
1020:2015
1007:ISBN
986:2015
961:2015
921:help
895:ISBN
835:2018
806:2014
784:2017
761:2014
710:ISBN
686:2015
625:ISBN
438:The
426:The
417:VTOL
411:The
395:The
387:The
128:drag
122:and
120:lift
617:doi
517:),
515:IMU
483:FPV
225:yaw
87:or
65:FPV
38:DJI
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