Hi. As a cofounder of a company making sensors and navigation systems for drones, I am fascinated by tiny flying robots. Such robots have many interesting applications. Military applications are kind of obvious (discreet surveillance, inspecting an indoor site controlled by hostile forces, ...), while concerning civilian ones you might be surprised...
To begin with, today I learned that the first drone insect was designed in the 70s by CIA. It was a miniature dragonfly, carrying a miniature listening device.
A working prototype was built, but eventually the project was abandoned because control was too difficult even with slight crosswinds.
Clearly, it´s hard to find information about more recent military insect drones. Personally, I am more interested in those systems which could be used to improve people´s life (search & rescue, agriculture,...).
Moving to our century...Harvard University has been developing a very interesting system called RoboBee.
This tiny fly-like system has two wafer-thin wings that flap almost invisibly, 120 times per second.
The first version was released in 2013. Further improvements have lead to a system which can currently fly, swim in water and cling to surfaces in order to save energy, as you can see below
You will notice that RoboBee is a tethered system, as the challenge of miniaturizing fuel cells or some other source of power in order to grant more than a couple of minutes of flight to a micro drone is still unsolved.
The most fascinating civilian application for such systems is, in my opinion, pollination. The bees population worldwide is fast shrinking, and this is a recipe for environmental disaster, as bees are the main pollinators in nature and most plants require pollination.
Researchers from the Warsaw University of Technology have been working on their B-Droid pollination robots for 4 years. A wheeled robot has already successfully pollinated garlic and strawberries. Now they are finalizing a flying version of it, which is a small quadcopter.
This system is not tethered, however the on-board battery allows only a couple minutes of flight.
Broadly speaking, precision farming is a very interesting application area for drones, and robotized pollination could really be a killer app!
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