ORNITHOPTERS

• An Ornithopter, or ornitotero - like Leonardo da Vinci termed them - is an aircraft heavier than air, that flies like a bird by flapping it's wings.

• The special feature lies in the wings that do not only generate lift but also thrust.

Bird’s Wing

Wing’s Flapping Mechanisms

The purpose of the flapping mechanism is to convert the rotary motion of the motor into the reciprocating motion of flapping wings.

The mechanism will be lightweight and fairly simple, and will provide a fairly symmetrical wing motion so that the ornithopter flies straight.

Mechanism of Flapping

The motor drives a rotating crank.

The crank has a connecting rod attached to it, and the other end of the connecting rod is attached to the wing.

As the crank goes around, the connecting rod pushes the wing up and down, to account for symmetry we shall use the dual crank system

Electric motors over IC engines

RC ornithopters powered by an electric motor, have more power, and are much quieter and more convenient than internal-combustion-powered ornithopters.

Future ornithopters will be smaller and smaller and will need to be powered by batteries.

Batteries

Lithium-polymer batteries will be used because of their comparatively high power to weight ratio.

Li-Poly batteries today supply something like 0.14 watt-hours per gram.

Ornithopters so far

Ornithopters so far…

Ornithopters so far…

Ornithopters so far…

Servos

High torque Micro Servos with strong gears

shall be used for the tail.• Servos will also be used to change shape

and size of the wings during flight.

• This is the difference we plan to incorporate in the ornithopter.

Size alteration of wings during flight.

Outer part of wings will have a mechanism similar to that employed in a hand fan.

Shape alteration of wings during flight

Video

Control Mechanism

For steering, swinging of the tail sideways will produce rolling movement.

Similarly, up-down movement will alter the nose direction.

The stability of the ornithopter will be achieved

with the help of the tail.

RC

RC shall be used to

control the flight.

Approximate dimensions

Wingspan of about 1-1.2m Length of about 0.6m Fuselage width of about 10cm

Cost estimate

Li-Poly batteries: ~ $ 250 Motor: ~ $ 175 Servos: ~ $ 100 RC system: ~$ 325 Flapping mechanism and gears: ~ Rs. 5000 Cost of material (fuselage, wings): ~

Rs. 15,000

Timeline

By 15th of May: Complete conceptual study and gathering of data, sketches, placement of orders.

By 15th of June: Non-powered prototype with gliding capabilities.

By 15th of July: flying wonder!