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Tiny, Morphing, Electricity-Stealing Spy Planes Developed
tkohler writes "The Air Force Research Lab is developing an Electric Motor-powered Micro Air Vehicle (MAV) that can 'harvest' energy when needed by attaching itself to a power line. It can also temporarily change its shape to look more like innocuous piece of trash hanging from the cable. For domestic spying, maybe it will morph into a pair of sneakers?"
Nice to see the govt has recruited the help of the Decepticons.
At the moment, this high tech surveillance equipment is cunningly disguised as a barrel full of pork.
If you haven't made a developer cry, you've wasted a day.
Challenges abound, though. Zac Richardson, a power-line engineer with National Grid in the UK, warns that if the MAV contacts an 11-kilovolt local power line, it could short circuit two conductors, causing an automatic disconnection of the very power the plane seeks.
Why do they assume the UAV would be conductive? Wouldn't your best bet for tapping energy off power lines be to simply use induction? You don't even need to land on the lines themselves; a fluorescent tube light will light up at yards from the power line.
Do National Grid power-line engineers not know of this?
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barefoot drug dealers no less
It's not made yet. I doubt even a prototype has been made yet.
Well, the prototype for the "stealing" part has already been developed. It's called Congress.
The theory of relativity doesn't work right in Arkansas.
From what I've heard around the county I live in, shoes on the powerlines indicates that there are drug dealers on whatever street they are hanging over.
Actually, it's the drug users that throw the shoes up there. Drug pushers are for some reason (a mystery to medical science) compulsively driven to powerlines with shoes hanging from them. Obviously this is seen as a big problem for the drug dealing community, which is trying to enter the 21st century, leveraging such fast-paced technologies as 'two-way pagers' and 'cellular telephones'. They find themselves involuntarily skulking around power lines in every sort of weather, knowing full well they could be successful drug deals in the back of the local chuck-e-cheese, but find themselves incapable of breaking the spell of such a powerful lure.
Or maybe it's some sort of urban legend or something, and it's just, like, kids with nothing better to do throwing up some shoes. Dunno.
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Cute idea. What they're trying to do, it seems, is mooch a little power from the electrostatic field gradient around the wire. This is quite feasible if you have a wire with a few KV to ground. The classic demo is to light up a fluorescent lamp by placing it vertically below a high tension line. This works partly because air is not a perfect insulator. There's an electrical path to ground; it just has a high resistance.
If the thing lands on an 11KV power line that's 10m above ground, and has a conductive part that dips 10cm below the line, it should see a voltage difference of about 90 volts. You can't draw very much current before the voltage difference disappears, but you can draw a little.
It's also possible to extract some energy magnetically. See U.S. Patent #3,202,963, "Apparatus for Illuminating Power Lines". But that approach requires heavier parts than an electrostatic approach.