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1 | Page BANSILAL RAMNATH AGARWAL CHARITABLE TRUST`S VISHWAKARMA INSTITUTE OF TECHNOLOGY PUNE- 411 037 (An Autonomous Institute Affiliated to University of Pune) Mini Project On Flying Wing MechanismSubmitted By Harshal Patil TE T-31 Pooja Patil TE T-33 Vijay Patil TE T-34 Priyanka Salve TE T-43 Under The Guidance of Prof. G. N. Kotwal Department of Mechanical Engineering 2013-2014
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Ornithopter flying wing mecahnism report

Jan 19, 2015

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Vijay Patil

a report on flying wing mechanism (ornithopter)
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BANSILAL RAMNATH AGARWAL CHARITABLE TRUST`S

VISHWAKARMA INSTITUTE OF TECHNOLOGY

PUNE- 411 037

(An Autonomous Institute Affiliated to University of Pune)

Mini Project

On

“Flying Wing Mechanism”

Submitted By

Harshal Patil TE T-31

Pooja Patil TE T-33

Vijay Patil TE T-34

Priyanka Salve TE T-43

Under The Guidance of

Prof. G. N. Kotwal

Department of Mechanical Engineering

2013-2014

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VISHWAKARMA INSTITUTE OF TECHNOLOGY

PUNE-411 037

(An Autonomous Institute Affiliated to University of Pune.)

CERTIFICATE

This is to certify that the Mini Project titled “Flying Wing Mechanism” has been completed in the

academic year 2013 – 2014, by Harshal Patil (Gr. No. 111675), Pooja Patil (Gr. No. 111229), Vijay

Patil (Gr. No. 111355) and Priyanka Salve (Gr. No. 111291) in partial fulfillment of Bachelors Degree

in Mechanical Engineering as prescribed by University of Pune.

Prof. G. N. Kotwal

(Guide)

Vishwakarma Institute of Technology, Pune

Prof. H. G. Phakatkar

(H.O.D. Mechanical Dept.)

Vishwakarma Institute of Technology, Pune

Place: Pune Date: 22/04/2014

________________

Examiner

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ACKNOWLEDGEMENT

Words are inadequate and out of place at times particularly in the context of

expressing sincere feelings in the contribution of this work, is no more than a mere

ritual. It is our privilege to acknowledge with respect & gratitude, the keen valuable

and ever-available guidance rendered to us by Prof. G. N. Kotwal without the wise

counsel and able guidance, it would have been impossible to complete the mini

project in this manner.

We express gratitude to other faculty members of Mechanical Engineering

Department for their intellectual support throughout the course of this work.

Finally, we are indebted to our family and friends and for their ever available

help in accomplishing this task successfully. We will be forever grateful to our friend

Mayuresh Marhadkar for his precious advice and for letting us do our project in The

Robocon Arena.

Above all we are thankful to the almighty god for giving strength to carry out

the present work.

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ABSTRACT

It is no surprise that humanity’s first attempts at flight were in the form of birdlike,

human-powered ornithopters. The great artist and engineer Leonardo da Vinci is

often credited as the first to propose a reasonable flying machine in 1490: a giant

bat-shaped craft that uses both the pilot’s arms and legs to power the wings. Though

the aircraft was never built, and we now know that it would not have flown, it was a

remarkable achievement considering the knowledge of the day. At the turn of the

20th century, focus shifted both in the method of thrust production, from flapping

wings to the propeller, and the method of power generation, from the human body to

the internal combustion engine. With the aerodynamic problem greatly simplified, the

impossibility of human flight was disproved by the Wright brothers’ flight in 1903 and

the stage was set for the boom of aircraft developments in the decades to come.

Though work on human-powered aircraft was still carried on from time to time by

several groups in various countries, it would be three-quarters of a century before

anyone mastered the art of human-powered flight.

The problem of flapping-wing flight has been tackled by countless engineers and

craftsmen, but until recently only moderate success had been achieved. The

Subsonic Aerodynamics laboratory under Professor James de Laurier at the

University of Toronto has been a prolific contemporary contributor to the body of

knowledge concerning flapping-wing flight, with successes in remote-controlled

ornithopters, flapping-wing micro air vehicles, and even a full-scale human-piloted

engine powered ornithopter. In 1991 the Professor De Laurier and UTIAS were

awarded the “Diplôme d’Honneur” by the FAI for having flown the world’s first

engine-powered remotely-piloted ornithopter. Theoretical and experimental research

intensified in subsequent years, culminating in the successful flight of a full-scale

piloted ornithopter on July 8th, 2006. A patented wing-twisting mechanism and

extensive research in aero elastic tailoring has kept the University of Toronto at the

forefront of ornithopter innovation for the last 20 years.

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Contents ACKNOWLEDGEMENT ............................................................................................................................. 3

ABSTRACT ................................................................................................................................................ 4

INTRODUCTION ....................................................................................................................................... 6

Flying on Flapping Wings .................................................................................................................... 6

Wing Design ........................................................................................................................................ 6

LITERATURE REVIEW ............................................................................................................................... 7

Manned flight ...................................................................................................................................... 9

Projects Worldwide ........................................................................................................................... 10

DelFly ............................................................................................................................................. 10

Robotic Insect................................................................................................................................ 11

Flapping Wings at ETH .................................................................................................................. 12

Aerodynamics of Flapping Wings .......................................................................................................... 13

Lift ..................................................................................................................................................... 13

PRESENT WORK ..................................................................................................................................... 14

ABOUT OUR PROJECT........................................................................................................................ 14

DIMENSIONS ..................................................................................................................................... 14

Components used ............................................................................................................................. 15

Advantages ............................................................................................................................................ 16

APPLICATION ......................................................................................................................................... 17

Applications for unmanned ornithopters ......................................................................................... 17

Ornithopters as a hobby ................................................................................................................... 19

Conclusion ............................................................................................................................................. 21

REFERENCES .......................................................................................................................................... 22

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INTRODUCTION

Flying on Flapping Wings

What is ornithopter?

An ornithopter (from Greek ornithos "bird" and pteron "wing") is an aircraft that flies by flapping its wings. Designers seek to imitate the flapping-wing flight of birds, bats, and insects. Though machines may differ in form, they are usually built on the same scale as these flying creatures. Manned ornithopters have also been built, and some have been successful. The machines are of two general types: those with engines and those powered by the muscles of the pilot. The research on Micro Aerial Vehicles (MAV) is comparably young, which has

emerged over the past few years. The ongoing miniaturization of electric

components such as electric motors and the improvements in microelectronics made

it possible to build miniature planes and helicopters at relatively low costs. This

development also made it possible to start imitating insect and bird flight, which

needs a sophisticated miniaturized actuation chain for their flapping wing motion.

The goal of this research is to come up with small aerial vehicles that can operate

independently from ground stations, performing certain operations such as

surveillance or measurement, especially in environments that are hardly accessible

or even dangerous for people.

Wing Design

Ornithopters 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. A flexible wing material can increase efficiency while keeping the driving mechanism simple. In wing designs with the spar sufficiently forward of the airfoil that the aerodynamic center is aft of the elastic axis of the wing, aero elastic deformation causes the wing to move in a manner close to its ideal efficiency (in which pitching angles lag plunging displacements by approximately 90 degrees). Flapping wings increase drag and are not as efficient as propeller-powered aircraft. Some designs achieve increased efficiency by applying more power on the down stroke than on the upstroke. 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. Any mass located to the aft of the empennage reduces the wing's performance, so lightweight materials and empty spaces are used where possible. In order to minimize drag and maintain the desired shape, choice of a material for the wing surface is also important. In De Laurier's experiments, a smooth aerodynamic surface with a double-surface airfoil is more efficient at producing lift than a single-surface airfoil.

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LITERATURE REVIEW

The Sanskrit epic Ramayana (4th Century BC) describes an ornithopter,

the Pushpaka Vimana. The ancient Greek legend of Daedalus (Greek demigod

engineer) and Icarus (Daedalus's son) and The Chinese Book of Han (19 AD) both

describe the use of feathers to make wings for a person but these are not actually

aircraft. Some early manned flight attempts may have been intended to achieve

flapping-wing flight though probably only a glide was actually achieved. These

include the flights of the 11th-century monk Eilmer of Malmesbury (recorded in the

12th century) and the 9th-century poet Abbas Ibn Firnas (recorded in the 17th

century). Roger Bacon, writing in 1260, was also among the first to consider a

technological means of flight. In 1485, Leonardo da Vinci began to study the flight of

birds. He grasped that humans are too heavy, and not strong enough, to fly using

wings simply attached to the arms. Therefore he 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.

Some early manned flight attempts may have been intended to achieve flapping-

wing flight though probably only a glide was actually achieved. These include the

flights of the 11th-century monk Eilmer of Malmesbury (recorded in the 12th century)

and the 9th-century poet Abbas Ibn Firnas (recorded in the 17th century). Roger

Bacon, writing in 1260, was also among the first to consider a technological means

of flight. In 1485, Leonardo da Vinci began to study the flight of birds. He grasped

that humans are too heavy, and not strong enough, to fly using wings simply

attached to the arms. Therefore he 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.

Leonardo da Vinci's ornithopter design

The first ornithopters capable of flight were constructed in France. Jobert in 1871

used a rubber band to power a small model bird. Alphonse Pénaud, Abel Hureau de

Villeneuve, and Victor Tatin, also made rubber-powered ornithopters during the

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1870s. Tatin's ornithopter (now in the US Air & Space Museum) 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. Gustave Trouvé was the first to use

internal combustion and his 1890 model flew a distance of 70 meters in a

demonstration for the French Academy of Sciences. The wings were flapped

by gunpowder charges activating a bourdon tube.

From 1884 on, Lawrence Hargrave built scores of ornithopters powered by rubber

bands, springs, steam, or compressed air. He introduced the use of small flapping

wings providing the thrust for a larger fixed wing. This eliminated the need for gear

reduction, thereby simplifying the construction.

E.P. Frost's 1902 ornithopter

E.P. Frost made ornithopters starting in the 1870s; first models power by steam

engines then in the 1900s an internal combustion one large enough for a person but

which did not fly.

In the 1930s, Alexander Lippisch and the NSFK in 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 methodical study.

Erich von Holst also working in the 1930s achieved great efficiency and realism in

his work with ornithopters powered by rubber band. This includes perhaps the first

success of an ornithopter with a bending wing, intended to more closely imitate the

folding wing action of birds although it was not a true variable span wing like birds

have.

Around 1960, Percival Spencer successfully flew a series of unmanned 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). In 1961,

Percival Spencer and Jack Stephenson flew the first successful engine-powered,

remotely piloted ornithopter, known as the Spencer Orniplane. The Orniplane had a

90.7 inches (2,300 mm) wingspan, weighed 7.5 pounds (3.4 kg), and was powered

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by a 0.35-cubic-inch (5.7 cm3) displacement 2-stroke engine. It has a biplane

configuration, to reduce oscillation of the fuselage.

Manned flight

Otto Lilienthal on August 16, 1894 with his kleiner Schlagflügelapparat

Schmid 1942 Ornithopter

Manned ornithopters fall into two general categories: Those powered by the

muscular effort of the pilot (human-powered ornithopters), and those powered by an

engine.

Around 1894, Otto Lilienthal, an aviation pioneer, became famous in Germany for his

widely publicized and successful glider flights. Lilienthal also studied bird flight and

conducted some related experiments. He constructed an ornithopter, although its

complete development was prevented by his untimely death on the 9th of August

1896 in a glider accident.

In 1929, a man-powered ornithopter designed by Alexander Lippisch (designer of the

Me163 Komet) flew a distance of 250 to 300 meters after tow launch. Since a tow

launch was used, some have questioned whether the aircraft was capable of flying

on its own. Lippisch asserted that the aircraft was actually flying, not making an

extended glide. (Precise measurement of altitude and velocity over time would be

necessary to resolve this question.) 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.

In 1942, Adalbert Schmid made a much longer flight of a human-powered ornithopter

at Munich-Laim. It travelled a distance of 900 meters, maintaining a height of 20

meters throughout most of the flight. Later this same aircraft was fitted with a

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3 hp (2.2 kW) Sachs motorcycle engine. With the engine, it made flights up to 15

minutes in duration. Schmid later constructed a 10 hp (7.5 kW) ornithopter based on

the Grunau-Baby IIa sailplane, which was flown in 1947. The second aircraft had

flapping outer wing panels.

In 2005, Yves Rousseau was given the Paul Tissandier Diploma, awarded by

the FAI for contributions to the field of aviation. Rousseau attempted his first human-

muscle-powered flight with flapping wings in 1995. On 20 April 2006, at his 212th

attempt, he succeeded in flying a distance of 64 meters, observed by officials of the

Aero Club de France. Unfortunately, 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.

A team at the University of Toronto Institute for Aerospace Studies, headed

by Professor James De Laurier, worked for several years on an engine-powered,

piloted ornithopter. In July 2006, at the Bombardier Airfield at Downsview

Park in Toronto, Professor De Laurier's machine, the UTIAS Ornithopter No.1 made

a jet-assisted takeoff and 14-second flight. According to De Laurier, the jet was

necessary for sustained flight, but the flapping wings did most of the work.

On August 2, 2010, Todd Reichert of the University of Toronto Institute for

Aerospace Studies piloted a human-powered ornithopter named Snowbird. The 32-

metre (105 ft 0 in) wingspan, 42-kilogram (93 lb) aircraft was constructed

from carbon fiber, balsa, and foam. The pilot sat in a small cockpit suspended below

the wings and pumped a bar with his feet to operate a system of wires that flapped

the wings up and down. Towed by a car until airborne, it then sustained flight for

almost 20 seconds. It flew 145 meters with an average speed of 25.6 km/h

(7.1 m/s) Similar tow-launched flights were made in the past, but improved data

collection verified that the ornithopter was capable of self-powered flight once aloft.

Projects Worldwide

With the ongoing miniaturization in robotics during the past years it became possible

to remarkably downsize aerial vehicles. Recently, several research groups have

been trying to build aerial vehicles that are based on the principle of flapping the

wings such as insects do. Two of these projects are the DelFly and from TU Delft

and the Robotic Insect from Harvard University.

DelFly

DelFly is a MAV developed at TU Delft in the Netherlands. It has four wings, which

are actuated by one electric motor. The wings are arranged in pairs, 3State of the Art

4 with the right upper wing connected to the left lower wing and vice versa. Via a

small gear train the wing pairs are connected to the electric motor so that the upper

and the lower wing approach towards each other. In forward flight, the course can be

controlled with rudders installed at the tail of the vehicle. DelFly also carries a

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camera onboard that sends images to a ground computer from where the vehicle is

controlled.

Figure 1: DelFly.

Robotic Insect

Another interesting project is the so called Robotic Insect, being developed at the

Harvard Micro robotics Laboratory. The underlying concept is the applying motion of

small insects such as flies. For the actuation of the wings of this very small scale

MAV a piezoelectric cantilever is used, inducing an oscillation of the wings at their

resonance frequency, in order to produce high amplitude. The joints are integrated in

the structure as exible parts. The power supply however is not included in this

vehicle, which means that despite of already producing remarkably high lift it is not

yet able to actually y.

Figure 2: Robotic Insect.

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Flapping Wings at ETH

The ASL at ETH also aims to develop a MAV of bird size that is based on the

aerodynamic principles used in insect flight and by small birds. Unlike other

developments in this area, the intended MAV at ETH shall be able to hover like

insects or Humming birds, and so it is supposed to become an interesting alternative

to Flapping Wings at ETH helicopters as currently being developed at ASL.

Furthermore, such an aerial vehicle should be large enough to carry some payload

such as a camera, but still small enough to have high agility. Hovering is closely

connected to unsteady aerodynamic effects at small Reynolds numbers used in

nature by insects and small birds. With a wingspan of 280mm and a weight of about

20g the Giant Hummingbird is one of the largest species in nature that can hover,

and therefore had been selected as natural ante type [2]. The goal, however, is not

to copy nature but to adopt the basic principles.

Figure 3: Female black-chinned Hummingbird in hover. (fromhttp://en.wikipedia.org)

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Aerodynamics of Flapping Wings

When flapping the wings, the airflow is highly turbulent and producing more lift

compared to wing flight. These are a consequence of the permanently changing

wing position during flapping, and are connected to the Reynolds number. In this

section the most important aerodynamic are described, however only as a short

introduction because this has already been subject to previous work by S. Gisler and

O. Breitenstein, where fairly detailed explanations can be found.

Lift

The lift that is produced by applying the wings is characterized by highly un-stationary aerodynamic effects which make it difficult to predict the resulting lift force for a given wing. In order to get a rough idea about what could be expected as lift, and therefore have a boundary for the total weight of the MAV, some simplifications are necessary, which allow applying the 2-dimensional airfoil theory with the formula for lift (L) L = (CL.ρ.v2.A)/2 With the air density ρ Airspeed v Platform area A And, The lift coefficient CL, for a specific angle of attack. The lift coefficient (CL, Ca or Cz) is a dimensionless coefficient that relates the lift generated by a lifting body to the density of the fluid around the body, its velocity and an associated reference area. A lifting body is a foil or a complete foil-bearing body such as a fixed-wing aircraft. CL is a function of the angle of the body to the flow, its Reynolds number and it’s Mach number. The lift coefficient CL is refers to the dynamic lift characteristics of a two-dimensional foil section, with the reference area replaced by the foil chord. The lift coefficient CL is defined by

, where is the lift force, is fluid density, is true airspeed, is platform area and is the fluid dynamic pressure. Applying equation for the Flapping wings requires the following assumptions:

1. Non stationary lifts that occur only when the wings are flapping are neglected, with the result that the resulting lift will likely be higher in reality.

2. The lift coefficient CL is independent of time and location on the wing. 3. Induced inflow is disregarded.

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PRESENT WORK

ABOUT OUR PROJECT

In our model there is one crank and connecting rods. Wings are attached to

connecting rods and the wings are hinged to two different slots. When we rotate the

crank, the second connecting rod oscillates. The oscillatory motion of connecting rod

leads to flapping of wings. Quick Return Mechanism is used here. The wings travel

faster during the downward stroke as compared to the upward stroke. This gives

more power during the downward stroke and hence gives lift.

DIMENSIONS

Crank radius= 4.5 cm

Length of connecting rod 1= 20 cm

Length of wing rod= 28 cm

Length of Wings= 30 cm

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Components used

Aluminum Linkages

Nut and bolts.

Lock nuts.

Vinyl Sheet (Wings)

Wooden Plank (Base)

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Advantages

Flapping wings offer potential advantages in maneuverability and energy savings

compared with fixed-wing aircraft, as well as potentially vertical take-off and landing.

It has been suggested that these advantages are greatest at small sizes and low

flying speeds.

Unlike airplanes and helicopters, the driving airfoils of the ornithopter have a flapping

or oscillating motion, instead of rotary. As with helicopters, the wings usually have a

combined function of providing both lift and thrust. Theoretically, the flapping wing

can be set to zero angle of attack on the upstroke, so it passes easily through the air.

Since typically the flapping airfoils produce both lift and thrust, drag-inducing

structures are minimized. These two advantages potentially allow a high degree of

efficiency.

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APPLICATION 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. Several ornithopters have been flown with

video cameras on board, some of which can hover and maneuver in small spaces. In

2011, AeroVironment, Inc. announced a remotely piloted ornithopter resembling a

large hummingbird for possible spy missions.

Practical applications capitalize on the resemblance to birds or insects.

The Colorado Division of Wildlife has used these machines to help save

the endangered Gunnison Sage Grouse. An artificial hawk under the control of an

operator causes the grouse to remain on the ground so they can be captured for

study.

Applications for unmanned ornithopters

Practical applications capitalize on the resemblance to birds or insects.

The Colorado Division of Wildlife has used these machines to help save

the endangered Gunnison Sage Grouse. An artificial hawk under the control of an

operator causes the grouse to remain on the ground so they can be captured for

study.

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. Several ornithopters have been flown with

video cameras on board, some of which can hover and maneuver in small spaces. In

2011, AeroVironment, Inc. announced a remotely piloted ornithopter resembling a

large hummingbird for possible spy missions.

AeroVironment Humming bird

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AeroVironment, Inc., then led by Paul B. MacCready (Gossamer Albatross)

developed in the mid-1980s, for the Smithsonian Institution, a half-scale radio

controlled replica of the giant pterosaur, Quetzalcoatlus northropi. It was built to star

in the IMAX movie On the Wing. The model had a wingspan of 5.5 meters (18 feet)

and featured a complex, computerized autopilot control system, just as the full-size

pterosaur relied on its neuromuscular system to make constant adjustments in flight.

Researchers hope to eliminate the motors and gears of current designs by

more closely imitating animal flight muscles. Georgia Tech Research

Institute's Robert C. Michelson is developing a Reciprocating Chemical Muscle for

use in micro-scale flapping-wing aircraft. Michelson uses the term "entomopter" for

this type of ornithopter. SRI International is developing polymer artificial muscles

which may also be used for flapping-wing flight.

In 2002, Krister Wolff and Peter Nordin of Chalmers University of

Technology in Sweden built a flapping wing robot that learned flight techniques. The

balsa wood design was driven by machine learning software technology known as a

steady state linear evolutionary algorithm. Inspired by natural evolution, the software

"evolves" in response to feedback on how well it performs a given task. Although

confined to a laboratory apparatus, their ornithopter evolved behavior for maximum

sustained lift force and horizontal movement.

Since 2002, Prof. Theo van Holten has been working on an ornithopter which

is constructed like a helicopter. The device is called the ornicopter and was made by

constructing the main rotor so that it would have no reaction torque at all.

In 2008, Schiphol Airport started using a real looking mechanical hawk

designed by falconer Robert Musters. The radio controlled robot bird is used to scare

away birds that could damage the engines of airplanes.

In March 2011, scientists and engineers at the Festo Bionic Learning

Network introduced a robotic SmartBird, based on the motion of a seagull. The

Smart Bird weighs only 450 grams and is controlled by a radio handset. On video, its

flight appears remarkably realistic.

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Ornithopters as a hobby

The Dragonfly is a toy made by Wow-Wee.

Hobbyists can build and fly their own ornithopters. These range from light-

weight models powered by rubber band, to larger models with radio control.

The rubber-band-powered model can be fairly simple in design and

construction. Hobbyists compete for the longest flight times with these models. An

introductory model can be fairly simple in design and construction, but the advanced

competition designs are extremely delicate and challenging to build. Roy White holds

the United States national record for indoor rubber-powered, with his flight time of 21

minutes, 44 seconds.

Commercial free-flight rubber-band powered toy ornithopters have long been

available. The first of these was sold under the name Tim Bird in Paris in 1879. Later

models were also sold as Tim Bird (made by G de Ruymbeke, France, since 1969).

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 wings are usually driven by an electric motor. Many hobbyists

enjoy experimenting with their own new wing designs and mechanisms. The

opportunity to interact with real birds in their own domain also adds great enjoyment

to this hobby. Birds are often curious and will follow or investigate the model while it

is flying. In a few cases, RC birds have been attacked by birds of prey, crows, and

even cats. More recent cheaper models such as the Dragonfly from WowWee have

extended the market from dedicated hobbyists to the general toy market.

Some helpful resources for hobbyists include The Ornithopter Design Manual,

book written by Nathan Chronister, and The Ornithopter Zone web site, which

includes a large amount of information about building and flying these models. To

see video examples of a remote control Ornithopter visits the Birds You Fly website.

Ornithopters are also of interest as the subject of one of the events in the

nationwide Science Olympiad event list. The event ("Flying Bird") entails building a

self-propelled ornithopter to exacting specifications, with points awarded for high

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flight time and low weight. Bonus points are also awarded if the ornithopter happens

to look like a real bird.

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Conclusion

Sooner or later, maybe - in the nearest future, manned motor ornithopters will cease

to be "exotic", imaginary, unreal aircraft and start to service for humans as a junior

member of aircraft family. Necessary high aviation technology already exists.

Designers and engineers will be forced to solve not only, for example, wing design

problem, but all problems peculiar to any safe and reliable aircraft of any type. Parts

of them, such as stability, controllability, durability etc. are inherent to all aircraft with

no exemption. The second part - specific “ornithopter” new problems, unknown

before, which will appear at the first time; flapping wing design problem is only one of

them.

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REFERENCES

1. "Flying on Flapping Wings” Ankit Bhardwaj- IIT Patna. (2012).

2. "An Ornithopter Wing Design" De Laurier, James D. (1994), 10–18.

3. “Winged robot learns to fly” New Scientist, August 2002.