Ornithopter
He, therefore, sketched a device in which the aviator lies down on a plank and works two large, membranous wings using hand levers, foot pedals, and a system of pulleys.
In 1841, an ironsmith kalfa (journeyman), Manojlo, who "came to Belgrade from Vojvodina",[2] attempted flying with a device described as an ornithopter ("flapping wings like those of a bird").
Refused by the authorities a permit to take off from the belfry of Saint Michael's Cathedral, he clandestinely climbed to the rooftop of the Dumrukhana (import tax head office) and took off, landing in a heap of snow, and surviving.
[4] Tatin's ornithopter was perhaps the first to use active torsion of the wings, and apparently it served as the basis for a commercial toy offered by Pichancourt c. 1889.
From 1884 on, Lawrence Hargrave built scores of ornithopters powered by rubber bands, springs, steam, or compressed air.
E. P. Frost made ornithopters starting in the 1870s; first models were powered by steam engines, then in the 1900s, an internal-combustion craft large enough for a person was built, though it did not fly.
[6] In the 1930s, Alexander Lippisch and the National Socialist Flyers Corps of Nazi Germany constructed and successfully flew a series of internal combustion-powered ornithopters, using Hargrave's concept of small flapping wings, but with aerodynamic improvements resulting from the methodical study.
[7] Around 1960, Percival Spencer successfully flew a series of uncrewed ornithopters using internal combustion engines ranging from 0.020-to-0.80-cubic-inch (0.33 to 13.11 cm3) displacement, and having wingspans up to 8 feet (2.4 m).
Most of the subsequent human-powered ornithopters likewise used a tow launch, and flights were brief simply because human muscle power diminishes rapidly over time.
On 20 April 2006, at his 212th attempt, he succeeded in flying a distance of 64 metres (210 ft), observed by officials of the Aero Club de France.
On his 213th flight attempt, a gust of wind led to a wing breaking up, causing the pilot to be gravely injured and rendered paraplegic.
[14] A team at the University of Toronto Institute for Aerospace Studies, headed by Professor James DeLaurier, worked for several years on an engine-powered, piloted ornithopter.
In July 2006, at the Bombardier Airfield at Downsview Park in Toronto, Professor DeLaurier's machine, the UTIAS Ornithopter No.1 made a jet-assisted takeoff and 14-second flight.
[18] Because ornithopters can be made to resemble birds or insects, they could be used for military applications such as aerial reconnaissance without alerting the enemies that they are under surveillance.
Led by Paul B. MacCready (of Gossamer Albatross fame), AeroVironment developed a half-scale radio-controlled model of the giant pterosaur, Quetzalcoatlus northropi, for the Smithsonian Institution in the mid-1980s.
Georgia Tech Research Institute's Robert C. Michelson is developing a reciprocating chemical muscle for use in microscale flapping-wing aircraft.
In 2002, Krister Wolff and Peter Nordin of Chalmers University of Technology in Sweden, built a flapping-wing robot that learned flight techniques.
Although confined to a laboratory apparatus, their ornithopter evolved behavior for maximum sustained lift force and horizontal movement.
[26][27] In 2012, RoBird (formerly Clear Flight Solutions), a spin-off of the University of Twente, started making artificial birds of prey (called RoBird®) for airports and agricultural and waste-management industries.
[28][29] Adrian Thomas and Alex Caccia founded Animal Dynamics Ltd in 2015, to develop a mechanical analogue of dragonflies to be used as a drone that will outperform quadcopters.
Roy White holds the United States national record for indoor rubber-powered, with his flight time of 21 minutes, 44 seconds[citation needed].
Commercial radio-controlled designs stem from Percival Spencer's engine-powered Seagulls, developed circa 1958, and Sean Kinkade's work in the late 1990s to present day.
The event ("Flying Bird") entailed building a self-propelled ornithopter to exacting specifications, with points awarded for high flight time and low weight.
It has been suggested that these advantages are greatest at small sizes and low flying speeds,[32] but the development of comprehensive aerodynamic theory for flapping remains an outstanding problem due to the complex non-linear nature of such unsteady separating flows.
[35] An ornithopter's flapping wings and their motion through the air are designed to maximize the amount of lift generated within limits of weight, material strength and mechanical complexity.
[34] In order to achieve the desired flexibility and minimum weight, engineers and researchers have experimented with wings that require carbon fiber, plywood, fabric, and ribs, with a stiff, strong trailing edge.
Ornithopters with thinner wings have a limited angle of attack but provide optimum minimum-drag performance for a single lift coefficient.
Ornithopters have been depicted in fiction several times, including Frank Herbert's Dune series, where they are the primary form of air transportation used by House Atreides in the desert climate of the planet Arrakis.
