The phrase micro air vehicle (MAV) taken literally, brings to mind "very small planes." That image is much too simplified. Yes, these vehicles are small. In fact, to be defined as MAVs by the Defense Advanced Research Projects Agency (DARPA), they must be less than 15 cm (about 6 in.) in length, width, or height. The mass of these tiny vehicles is 50 grams or less.

MAVs are like mechanical bugs - robots with wings! The possible uses for these swarming, techno-transits are limitless.

MAVs can obviously fly into spaces too small for traditional planes. They can travel into burning buildings and over dangerous terrain. Via mounted cameras, they can serve as the eyes of those left behind at ground stations. By virtue of their size, they are nearly invisible a few hundred feet above the ground and difficult to detect with radar. Many radar systems can't tell an MAV from a bird or bat.

Some see these planes serving as traffic monitors, helping in search and rescue missions, surveying wildlife migrations, inspecting power lines, and even taking real-estate aerial photos. Several NASA Research Centers are eyeing MAVs for their ability to fly over alien planets like Mars.

The challenge to design and create these tiny vehicles pushes the limits of technology. Shrinking the size and weight of a wing, while expecting it to carry a small payload, has proven difficult for engineers. For help, scientists have studied birds, bats, and insects in flight, hoping to learn from what nature does best. Researchers are trying to mimic the ability of bees and wasps to carry, proportionately, huge cargo loads. Even 90-degree turns are easy for a fruit fly. Many insects stay aloft even when parts of their wings are damaged or missing.

Will scientists be able to mimic nature's amazing feats with their tiny flying robots?

Robert Michelson, along with his design team from the Georgia Tech Research Institute (GTRI), University of Cambridge (England), and ETS Labs is designing a flying and crawling mechanical insect called the "Entomopter." Using a Reciprocating Chemical Muscle this machine flies to the beat of a wing powered by a chemical energy source. Small amounts of electricity enable this wing actually to flap as it flies.
Would such an MAV be able to navigate the skies of Mars? Staying aloft in the thin Martian atmosphere, with traditional wings, would demand a speed of nearly 250 mph.

By using the rapidly beating wings of the Entomopter, this speed could be reduced. The Entomopter's insect-like wings can flap rapidly, allowing more lift with less speed. Not only could an MAV modeled after the Entomopter fly through the Martian skies, but with the reduced gravity of Mars, it might also be able to land, take samples, recharge, and fly again. Controlled remotely, operators could call it back to its original launch point and refuel and restock it for its next flight.

Once again, technology scrambles to do what nature does effortlessly.

What do you think?

How are micro air vehicles (MAVs) different from traditional airplanes?
How are some of these differences beneficial?
What problems are engineers having with the design and building of MAVs?
How would you use an MAV?