Micro air vehicles, also known as MAVs, result from the US military's interest in miniature spying devices. The Defense Advanced Research Projects Agency (DARPA) has heavily funded some of these projects. Small radio-controlled ornithopters can carry a camera payload for spying inside buildings. The ultimate goal is to produce an ornithopter so small and lifelike that it can pass as a real insect or small bird, going unnoticed as it performs its deadly mission. With recent advances in hobby radio control products, now you can build your own micro-sized ornithopters and hopefully find some non-violent purpose for them.
 

		2000. The MicroBat, developed by Aerovironment and Caltech, was the first micro-sized ornithopter resulting from MAV funding. It had three-channel radio control and used one of the lithium-polymer batteries which had just become available.
		2000s. At the International Micro Air Vehicle Competition, university teams compete to see who can perform the most pylon circuits with the smallest ornithopter. This annual event is held in a different location each year and also includes rotary-driven MAVs. (University of Florida entry is shown.)
		2002. Although some hovering freeflight ornithopters had been built by hobbyists, Mentor, developed at University of Toronto, was the first hovering ornithopter with radio control. Hovering is important for MAV applications that require maneuvering in tight spaces.
		2006. Delfly, developed at the Technical University of Delft and Wageningen University, is able to transition between hovering and forward flight. These ornithopters also carry a small video camera. The live images are analysed by a computer on the ground, giving Delfly the capacity for autonomous navigation.
		2007. This prototype developed by Nathan Chronister can hover and perform aerobatic maneuvers. Though developed for recreational use, this ornithopter achieved a MAV benchmark because it is the size and weight of a real hummingbird. The ornithopter weighs 3.3 grams and has a 15 cm wingspan.
		2007. Currently the world's smallest radio-controlled ornithopter, this one constructed by Petter Muren has a wingspan of 10 cm and weighs only 1 gram.
		2010. Aerovironment's Nano Hummingbird, while not especially small, was a huge breakthrough in MAV ornithopter research because of its gyroscopically stabilized flight without any tail surfaces.