A small insect or a mosquito over your ear may now be much more than simply annoying. Those could easily be micro drones which now come in a swarm of bug-sized flying spies.

­In an effort to create a hard-to-detect surveillance drone that will operate with little or no direct human supervision in out of the way and adverse environments, researchers are mimicking nature. The University of Pennsylvania GRASP Lab showed off a network of 20 nano-quad rotors capable of agile flight, which could swarm and navigate in an environment with obstacles.This is another step away from bulky heavily armed aerial vehicles or humanoid robots to a much smaller level of tiny remote-control devices. While current drones lack manoeuvrability, can’t hover and move fast enough, these new devices will be able to land precisely and fly off again at speed. One day the military hope they may prove a crucial tactical advantage in wars and could even save lives in disasters. They can also be helpful inside caves and barricaded rooms to send back real-time intelligence about the people and weapons inside.A report in NetworkWorld online news suggests the research is based on the mechanics of insects, which potentially can be reverse-engineered to design midget machines to scout battlefields and search for victims trapped in rubble. In an attempt to create such a device, scientists have turned to flying creatures long ago, examining their perfect conditions for flight, which have evolved over millions of years.Zoologist Richard Bomphrey has told the British Daily Mail newspaper he has conducted research to generate new insight into how insect wings have evolved over the last 350 million years. “By learning those lessons, our findings will make it possible to aerodynamically engineer a new breed of surveillance vehicles that, because they are as small as insects and also fly like them, completely blend into their surroundings," the newspaper quotes him as saying.The US Department of Defense has turned its attention to miniature drones, or micro air vehicles long ago.Image from video of a swarm of Nano Qardrotors, posted at GRASP Laboratory website ­As early as in 2007 the US government was accused of secretly developing robotic insect spies when anti-war protesters in the US saw some flying objects similar to dragonflies or little helicopters hovering above them. No government agency has admitted to developing insect-size spy drones though some official and private organizations have admitted that they were trying.In 2008, the US Air Force showed off bug-sized spies as "tiny as bumblebees" that would not be detected when flying into buildings to "photograph, record, and even attack insurgents and terrorists." The same year US government's military research agency (DARPA) conducted a symposium discussing 'bugs, bots, borgs and bio-weapons.'Around the same time the so-called Ornithopter flying machine based on Leonardo Da Vinci’s designs was unveiled and claimed they would be ready for roll out by 2015Lockheed Martin's Intelligent Robotics Laboratories unveiled "maple-seed-like" drones called Samarai that also mimic nature. US troops could throw them like a boomerang to see real-time images of what's around the next corner. The US is not alone in miniaturizing drones that imitate nature: France, the Netherlands and Israel are also developing similar devices.An image from NetworkWorld.com