AeroVironment, the California-based company behind the
largest, highest and longest flying unmanned aircraft system
(UAS), the
Global Observer, has now achieved a remarkable technical
milestone with a much smaller aircraft. With its "Nano
Hummingbird" the company has for the first time achieved
controlled precision hovering and fast-forward flight of a
two-wing, flapping wing aircraft that carries its own energy
source and relies only on its flapping wings for propulsion and
control.
The hand-made final concept demonstrator Nano Hummingbird has
a wingspan of 16 cm (6.5 in) and weighs just 19 g (2/3 oz),
which is less than the weight of a AA battery. Into this tiny
and lightweight package the AeroVironment UAS team has managed
to cram all the systems required for flight, including
batteries, motors, communications systems and even a video
camera.
The aircraft can climb and descend vertically, fly sideways
left and right, fly forward and backward, as well as rotating
clockwise and counter-clockwise – all under remote control and
while carrying a video camera payload. It is even capable of
doing a 360-degree loop.
The Nano Hummingbird can be fitted with a removable body
fairing, which is shaped to have the appearance of a real
hummingbird and, although it is larger and heavier than an
average hummingbird, the aircraft is actually smaller and
lighter than the largest hummingbird found in nature.
The achievement was part of the Phase II contract awarded by
DARPA to AeroVironment to design and build a flying prototype
“hummingbird-like” aircraft for the Nano Air Vehicle (NAV)
program.
To meet the technical goals of the contract AeroVironment
needed to:
Demonstrate precision hover flight within a virtual
two-meter diameter sphere for one minute.
Demonstrate hover stability in a wind gust flight which
required the aircraft to hover and tolerate a two-meter per
second (five mph) wind gust from the side, without drifting
downwind more than one meter.
Demonstrate a continuous hover endurance of eight
minutes with no external power source.
Fly and demonstrate controlled, transition flight from
hover to 11 mph (17.7 km/h) fast forward flight and back to
hover flight.
Demonstrate flying from outdoors to indoors, and back
outdoors through a normal-size doorway.
Demonstrate flying indoors 'heads-down' where the pilot
operates the aircraft only looking at the live video image
stream from the aircraft, without looking at or hearing the
aircraft directly.
Fly the aircraft in hover and fast forward flight with
bird-shaped body and bird-shaped wings.
AeroVironment
says that not only did its Nano Hummingbird meet all of these
requirements, but that it also exceeded many of them.
Check out the two videos below to see the Nano Humminbird in
action. The first video from 2009 shows the Nano Hummingbird at
an early stage of development, while the second video shows a
flight of the final concept demonstrator.