Hand-launched UAV - The RQ-11B Raven

Since production of the AeroVironment RQ-11B Raven began in 2004, more than 13 000 units have been built. These small hand-launched remote-controlled unmanned aerial vehicle or SUAV were originally developed for the US military but have now been adopted by several other countries.

The Raven is now widely used by the US military for reconnaissance, scouting, surveillance, and target acquisition purposes both day and night. It can fly for about 60-90 minutes in an operational radius of 10 km (6 miles). The Raven can either be remote-controlled from the ground or fly autonomous missions using GPS waypoint navigation. Its small 1.9 kg (4.2 pounds) airframe usually harnesses CCD color video cameras and infrared night vision camera. The aircraft is powered by a small propeller located at the back of the wings.

Landing for the RQ-11B is not a problem as it can automatically fly itself to a predetermined landing point and perform a near vertical (1 foot down, 1 foot forward) "Autoland" descent. If its wings snap or break off on landing, a new one can easily be attached.

Video: SmartBird flight further explained

Festo's Smartbird - An Ultra Realistic Seagull Robot

A new robotic seagull called the SmartBird designed by the German company Festo that also created the autonomous robotic jellyfish and the elephant-trunk-inspired robotic arm is one of the most realistic animal inspired flying machines ever. To be specific, the robot is modelled after the herring gull and its flight motions and appearance is extremely similar to the real bird. Besides its startling similarities to a real bird, another amazing feature of the robot is that it can take off and land autonomously without any additional drive systems.

To achieve flight, Festo designed the robot with wings that not only beat up and down, but bend at specific spots just like what the wings of a normal bird do in flight. When flying, a lever mechanism increases the degree of deflection from the torso to the wing. The wings can also twist in such a way that during the upwards stroke, the leading edge of the wing is slightly upwards. This is called a positive angle of attack.

Direction can be changed by the opposing motion of the head and torso of the bird. This movement is synchronised by cables and two electric motors. The tail's movements also help change directions. It can tilt left or right to initiate turns or move left to right to generate yaw. The tail also acts as stabilizer and a pitch elevator.

The robot has a wing span of about 2 m (6.5 feet), which is much larger than an actual herring gull, and has a weight of about 400 g (1 pound). To achieve this weight, the company used lightweight carbon fibre in the body of the bird.

All these design features result in a robot that is light and agile with excellent aerodynamic qualities. In developing the Smartbird, the company says it has successfully deciphered bird flight, "one of the oldest dreams of humankind". They also say that the development of this technology with its functional integration of coupled drive units yields significant ideas and insights that the company can then apply to hybrid drive technology.