Micro Plane That Perches On Power Lines

An anonymous reader wrote in to tell us about a microplane that perches on power lines to recharge its batteries being developed as a surveillance device at MIT. As you can imagine, landing on a power line is hard to do ... and charging off transmission lines has its own problems.

Comments

Perch?

[Monkeedude1212]

Would it be easier if it were more bat-like, hanging from the line instead of perching?

Re:Perch?

[swanzilla]

The 'perch' is actually quite bat-like. FTA:

The MIT engineers' answer is to send their 30-centimetre-wide micro air vehicle (MAV) into a controlled stall, pointing its nose up at just the right point in its trajectory to collide with and hook onto the cable.

Once it hooks the cable, it is a passive system. Check the video...it hasn't been /.ed (yet.)

Re:Perch?

[Anonymous Coward]

According to the article it does hang by the nose. No mention of how it gets off the power line though.

This won't work anyway because wind is going to make it much more difficult (damn near impossible with current technology). To add to that, power lines are often in wide open spaces where there will be even more wind. Hanging a glider (which presumably has large surface area wings) off power lines in windy conditions just seems like a really bad idea.

I seriously doubt they will even get past the stage of attaching this thing to a real full-scale line.

Re:Perch?

[nedlohs]

It does hang, just from a hook near the nose so it isn't upside down.

Which would make actually hooking up *much* easier, since you need to be nose up which is why you can stall.

Hooking up upside down would be really hard, pointing your nose down makes slowing down just a tad difficult.

What I don't understand is how it is going to take off again. It'd need to unhook and flip nose down before it hit the ground with enough height left to get the speed to generate lift. That doesn't seem like such an easy thing to do...

Re:Perch?

[wvmarle]

Seeing that video I think it's indeed going to hang. There seems to be a hook at the plane's belly to hook onto the cable.

It's a hard trick. I wonder how many tries for that video to work out - that mattress won't be there just because. And this is indoors, no wind, no movement of the wire. The wind will be the hardest: wind changes all the time, and will be influenced by the cable at close range. I can imagine quite some turbulence to overcome for the aircraft.

I wonder how often birds have to practice before they can land on a wire. The flying, the timing, the following of the wire as it swings in the air... it's not easy. And then many birds have the advantage that they can hover, even if only for a short while, in a way a fixed wing craft can never do. The bird has a lot of time for last-moment correction, a fixed wing craft not. It falls off and will have to turn around (a tricky manoeuvre in itself, after serious stalling, nose up in the air, and probably taking a hit from the cable it tried to hook on to) and try again.

No matter what it's an impressive trick, even in such a controlled environment.

Re:Perch?

[datapharmer]

think harrier.

Re:Perch?

[wvmarle]

Hooking up nose down may be easier, come to think of it. Because then what you should do is basically land on top of the wire with a small forward speed, letting your aircraft slide forward until the hook mounted all the way at the tail catches the wire. Presto, hanging nose down.

Getting off would be simple as well that way: retract the hook, fall down making speed, and just pull up the nose. Now just make sure you hang on a high enough wire.

Taking off hanging nose up is a bit harder, I would guess a tail flip - also a quite standard manoeuvre but requires more height. Unless your engine is so powerful that you can accelerate straight up. Not likely for such a craft.

Re:Perch?

[causality]

The 'perch' is actually quite bat-like. FTA:

The MIT engineers' answer is to send their 30-centimetre-wide micro air vehicle (MAV) into a controlled stall, pointing its nose up at just the right point in its trajectory to collide with and hook onto the cable.

Once it hooks the cable, it is a passive system. Check the video...it hasn't been /.ed (yet.)

This is all very interesting but ... do we really need another way to spy on people? One would wonder how the hell our ancestors managed to survive without living in a surveillance society.

<hypothetical>It's getting to the point that there may be a market for portable personal EMP devices when battery or supercapacitor technology advances enough. Just fire an EMP burst every so often and take out any such devices that may be near you, assuring your privacy that shouldn't have been threatened in the first place. If that harms cell phones or the computers controlling car engines and such, just do what the government does and call it "collateral damage" in the "war for privacy". You'd be putting it in terms that they understand.</hypothetical>

Re:Perch?

[Anonymous Coward]

Well they do hang, just with the front up.

I'm fairly sure this is a continuation from an older story on here: http://hardware.slashdot.org/story/07/11/24/0053218/Robot-Planes-and-Helicopters-Taught-Aerobatics

The video was pretty neat.

Re:Perch?

[TheCarp]

Not to mention that stealing power through induction is nothing new, and nothing that the people who are trying to sell that power are too keen on you trying. I mean, I can see the military not really caring too much about that aspect for their operations, but such a scheme would need some way to pay for it if you wanted to use it domestically.

-Steve

Re:Perch?

[nospam007]

"One would wonder how the hell our ancestors managed to survive without living in a surveillance society. "

They believed that some old man in the sky was watching them all the time.

Re:Perch?

[cgenman]

The story references a military story, where they talk about developed technologies that deform the wings into limp hanging detritus. That should diffray the issue of wind once attached to a line.

MIT students have actually been developing robot planes like this for years. They can prop-hang and take off vertically. They can hook vertically onto walls. They can fly quickly around indoors. Wind, then, is just one more problem to tackle.

Re:Perch?

[cgenman]

Spin the propeller up. Take off vertically. RC planes have enough power in the nose to do that.

Re:Perch?

[Xibby]

Shouldn't be a problem to take off from the power line. The electric motors used in R/C airplanes can generate enough thrust to hover a plane and all it's gear. Build the drone with two electric motors and counter rotating props and you could take off vertically (as well as hover) at full thrust (if that). Go up 50 feet, then turn off one of the motors to spin into nose dive position and kick the elevator to full climb to get back to horizontal flight. The great thing about R/C plans (and drones) is you can do crazy stunts that would make a human pilot motion sick, black out, or outright kill them.

Re:Perch?

[nedlohs]

If it can VTOL, then you don't need to bother hooking up with a controlled stall, so no.

Re:Perch?

[nedlohs]

Except if that is what you have, why are you be risking a stall to hook up, instead of just hovering and slowly descending until you hook up?

Re:Perch?

[Xibby]

I'm over thinking it. Here's a R/C plane going from VTOL to normal flight and back to VTOL.

http://www.technovelgy.com/ct/Science-Fiction-News.asp?NewsNum=1322

Re:Perch?

[causality]

Are you off of your meds or something?

First, UAVs have got WAYYYYYYY more uses than spying on people. Unmanned utility wire monitoring, atmospheric replacements for satellites, land surveys, search and rescue, etc. etc. etc. Spying is just a little teeny tiny subset of the things you can do with a UAV (for instance, we're using predator drones over the gulf right now to monitor the oil spill...we're doing this because they drones can stay in the air for a very long time).

Second, you're advocating a device that would indiscriminately destroy electronic equipment with a range long enough that it could take out a airplane. Are you fucking insane? People with pacemakers, or artificial hearts...just kill them?

Destroy everybody within 200 yards' telephone, laptop, pager, e-reader, etc. because you're paranoid that some scary OMG GUBBMINT guy is watching you buy a donut?

Stay classy, slashdot.

You don't handle tongue-in-cheek sarcasm very well, do you?

Re:Perch?

[blhack]

Not likely for such a craft.

I wouldn't be so sure about that... The thing is made from very low-weight foam and brushless motors are getting to the point where this is a reality. Those little toy Air Hogs things, for instance, can do this (albeit on a much smaller scale). /Sidebar: wtf has happened to those things? 2 years ago, they were all over the place, now the only thing I ever see are those god-awful 2-axis helicopters.

Re:Perch?

[Anonymous Coward]

Wind, then, is just one more problem to tackle.

LOL, I guess you have never actually tried any of this then?

Wind is the problem. It's the hardest of all and is why none of these projects have solved it.

Re:Perch?

[magarity]

Exactly... and to be more specific: all it needs is positive thrust to weight. Then taking off straight up is possible. Just need to drop enough to go around the wire from which it has just hung.

Re:Perch?

[marcobat]

They believed that some old man in the sky was watching them all the time.

We now know they were right

Re:Perch?

[drukawski]

Why don't you just saunter on down to Cambridge, MA and let everyone in the Computer Science and Artificial Intelligence Laboratory know that in 5 minutes you've figured out what they have been working on for months and that additionally, their doing it wrong.
Let me know how that goes for ya.

Also, this article isn't about planes that charge on power lines, its about some students that figured out how to automate the landing/perching maneuver on a small foam ultra light-weight rc unpowered glider.

The glider has no means of propulsion what-so-ever;
it has only 1 control surface, the elevator;
it has a tiny battery just large enough to run the servo and radio receiver;
it can't land in wind, rain, snow, or other real world conditions; AND
all of the sensing and control electronics (high speed motion detection cameras and Matlab running on a laptop) are mounted off-plane.

The reason landing a UAV on powerlines is hard isn't because the powerline are particularly difficult to hit, its because you have to design the landing system to work in real world weather conditions AND you can't have 20 some high speed motion capture cameras already at the landing site AND the thing still has to have all the normal electronics on board to fly after landing AND you have to cram on the large heavy (from a small UAV perspective) battery charging equipment as well.

For anyone interested the ACTUAL website for the ACTUAL study can be found here: http://groups.csail.mit.edu/locomotion/perching.html

Re:Perch?

[fuzzyfuzzyfungus]

“Religion is regarded by the common people as true, by the wise as false, and by the rulers as useful.” -Seneca.

Re:Perch?

[shmlco]

You're kidding, right? You could have hundreds of these things flying around a city and a power company wouldn't even register the line loss...

Re:Perch?

[marcosdumay]

Too bad that EMP probably won't work against mobile equipment, but will toast everything connected to any power line near you.

Re:Perch?

[Anonymous Coward]

"One would wonder how the hell our ancestors managed to survive without living in a surveillance society. "

They believed that some old man in the sky was watching them all the time.

Since we no longer believe in that, we have to have government to keep check on everybody.

Re:Perch?

[marcosdumay]

It is probably light and powerfull enough to keep itselt flying even with the nose up (ok, not just like an helicopter, but with the same apearence).

Re:Perch?

[0xdeadbeef]

One would wonder how the hell our ancestors managed to survive without living in a surveillance society.

Every primitive society is a surveillance society. We invented privacy when we invented walls.

So I guess the answer to your questions is, quite well, for between three and four billion years.

Re:Perch?

[marcosdumay]

You don't need two motors if you can adjust the airelons to compensate the motor rotation. That can be quite a feat to a human, but easy with a computer.

Re:Perch?

[TheCarp]

Yes but this is only a prototype. The technology has a lot of potential, and the question then becomes... if one application is small and its ok to steal tiny amounts of power that are unnoticeable over line loss, where do you draw the line? Should it just be free for all and we decide later if its a problem? What will we do when someone develops a "floating fortress" that deploys hundreds of these and tethers them to run from and recharge itself?

Would it be acceptable to setup a fleet of these glide up, charge some batteries, then come back and get new ones and supply a constant battery power? If thats acceptable too, becuase its so small, how do you tell the next guy he can't do the same, and the next?

-Steve

Re:Perch?

[ColdWetDog]

For anyone interested the ACTUAL website for the ACTUAL study can be found here: http://groups.csail.mit.edu/locomotion/perching.html

Thank you for that. This is what should be the gist of TFA instead of a breathless summary perched in front of a login screen.

The home made windtunnel is excellent!

Re:Perch?

[westlake]

This is all very interesting but ... do we really need another way to spy on people? One would wonder how the hell our ancestors managed to survive without living in a surveillance society.

Your ancestors never knew what it was like to live outside a surveillance society.

They might be Irish and Catholic, Russian and Jewish, Baptist and Negro - but the densely packed urban neighborhoods they inhabited were small towns writ large.

The small town knows you by sight from the day you are born. It can recite every breath of scandal that has touched your family for the last five generations.

There is one school, one church, one doctor, a general store, a post office....

a saloon, and a gin mill....

The saloon crowd more or less respectable and well-behaved. The gin mill - the road house just out of town - known to one and all for its drunkenness and danger.

 

Re:Perch?

[cgenman]

It is definitely the biggest problem. But you make it sound like A.I.: something that has been worked on and has remained elusive for a half-century. Realistically speaking, precision close-range acrobatic RC flight has been worked on at MIT for about 7 years. A lot of that has been in groundwork that, unlike AI, actually seems to work.

Wind is a major problem. But it seems premature to say that the project "wont work" because of it. Maybe it needs an internal accelerometer to judge wind offset. Maybe it needs to drop some chaff and do some velocity calculations. Maybe we need to increase the amount of control systems over a regular aircraft to give the computer the tools to deal with wind. Or maybe it just keeps moving until it finds a spot without a lot of wind. Wind doesn't seem like the death of the project.

Re:Perch?

[element-o.p.]

Which would make actually hooking up *much* easier, since you need to be nose up which is why you can stall.

Well...yes, but not exactly. You can still in any flight attitude (that is, angle between the longitudinal axis of the airplane and the ground). The only criteria to stalling is that the angle of attack (the angle between the chord line of the wing and the relative wind) exceed ~14 degrees or so (the exact angle is a function of the airfoil). Aerobatic pilots can stall their airplane even if the nose is pointed at the ground. F-15 pilots, because an empty (or nearly so) F-15 has a thrust:weight ratio of greater than 1:1, can point the nose vertically and still not stall.

What I don't understand is how it is going to take off again. It'd need to unhook and flip nose down before it hit the ground with enough height left to get the speed to generate lift. That doesn't seem like such an easy thing to do...

Since they are essentially talking about R/C airplanes, I don't think it's really going to be that hard. R/C airplanes have had more in common with helicopters than full-scale airplanes for quite a while now :) If the engine and propeller can generate more thrust than the airplane weighs, then -- like the F-15 I mentioned before or a helicopter -- you can substitute thrust for lift until the airplane is moving fast enough to fly again.

Re:Perch?

[bar-agent]

Hooking up nose down may be easier, come to think of it. Because then what you should do is basically land on top of the wire with a small forward speed, letting your aircraft slide forward until the hook mounted all the way at the tail catches the wire. Presto, hanging nose down.

Yeah, that would be easier. But the video mentions that they plan to adapt this stall-out technique for landing drones in confined areas. You can land nose-down as well, of course, but this is called "crashing."

Re:Perch?

[radtea]

That's a rather juvenile way to put it as I don't know any serious Christian who honestly believes the transcendental God of the Bible is a corporeal being who levitates in Earth's atmosphere.... but okay. They believed "that some old man in the sky was watching them all the time." They did not believe that some old man in the sky was coming up with clever ways for them to watch their neighbors all the time.

There's a lot wrong with your claims. I guess you don't know very much about Christianity, either in contemporary practise or historically.

The Reverend Jerry Fallwell once described the establishment of the Kingdom of God after Armageddon as "moving his headquarters from planet Heaven to planet Earth." The literal role of the sky in various Protest Fundamentalist theologies is very important, as suggested by the terminology they use to describe then end of days.

So saying the GP's description is juvenile is incorrect: it is a fair reflection of extremely common beliefs amongst apparently sincere and serious mainstream Christian groups that are active in the United States today.

With regard to your second claim, I believe you ought to learn a little about the role of confession in Catholicism, particularly up to the time of the Reformation. There are perfectly sound sociological analyses of the institution that strongly suggest it was nothing but a means of social control via constant surveillance, by self and others.

So please, before you post about Christianity inform yourself as to what actual living Christians believe and have believed. That way you won't embarrass yourself quite so much with your ignorance of this widely held an diverse faith.

Re:Perch?

[Anonymous Coward]

Li-poly packs plus brushless motors make this possible. I think that is even the same model yak that I had. You get about a 5 minute ride for a 1.5 hour charge if memory serves. Seems like something that would have to hang a very long time. Maybe only take off when needed...

Re:Perch?

[Pingmaster]

http://en.wikipedia.org/wiki/Transformer I would like you to quickly read up on how a transformer works. It is basically two inductors with a common iron core. the electromagnetic flux created by the primary coil induces a current in the secondary coil. this is very similar in nature to the way inductive battery chargers and such work (minus the common iron core). Two coils are places relatively close together and one induces a current in the other by creating an electromagnetic field.

Now, to address your comment. An EMP (ElectroMagnetic Pulse) is a very short burst of EM from a source (generally considered very large and energetic). This radiation....radiates from the source and induces an electric current in any material that is susceptible to such. Therefore, the copper traces in circuit boards, wiring in cars, TV and radio antennas and so forth all pick up this pulse and create a current. If the induced current is energetic enough it can cause voltages inside solid state devices exceeding their maximums and destroying the circuitry.

Oddly enough, bigger things like household appliances will be less affected, since a) they are already built to handle high currents b) fairly well shielded since they are often built inside grounded steel cases which will protect the more delicate electronics (think faraday cage) and c) protected from outside overcurrent via the step-down transformer at the telephone pole, the 15A breaker in the house and the built in fuse that just about everything in your house that plugs into the wall has.

So i guess what I'm trying to say is, you have it backwards. mobile devices are likely the most vulnerable, while stuff connected to the power line will be barely affected (aside from blowing every fuse and breaker in your house)

Re:Perch?

[jewishbaconzombies]

Re: portable EMPs. Ya - the courts will take your privacy concerns into account when you kill half a dozen people with pacemakers near you.

Picked out the color of soap-on-a-rope yet?

Re:Perch?

[Anonymous Coward]

The Reverend Jerry Fallwell once described the establishment of the Kingdom of God after Armageddon as "moving his headquarters from planet Heaven to planet Earth."

Okay, you see right there? Those four words you used?

The Reverend Jerry Fallwell

Those four, yep, you've got it. That's where you went wrong. Making a broad assumption as to the beliefs of an entire religion on one very loud extremist nutjob with an agenda? Yeah. Free tip: Don't do that. You're not helping your case.

In fact, you're just making a mockery of yourself, right down to a parody of your own opinion, especially with that deliciously ironic line right before that:

I guess you don't know very much about Christianity, either in contemporary practise or historically.

Re:Perch?

[g0bshiTe]

Don't worry this will not really go anywhere. I fly R/C aircraft this things wingspan is so small that anything more than 5 mph wind would be too squirrely to fly. Notice all the videos are indoors with zero wind. I'd rather see this thing land on a line outside in real conditions. My bet it would land once out of a hundred attempts.

Re:Perch?

[Anonymous Coward]

I think, in that case, it would be more likely the powers that be would declare you an "enemy combatant" in the "War Against Privacy"

Re:Perch?

[wsanders]

And that's my ancestors are NOT known as "Bruce the Bridge Builder", "Bruce the Fence Builder" ....

Re:Perch?

[dwye]

And before the small town, there was the tribe and the band. Try keeping anything private when you all sleep in the same Great Hall, or in tents.

Privacy is a fairly recent development, and had lots of detractors (Athenian democracy, for one, since people meeting together yet separate from the rest could be hatching all sorts of conspiracies).

Re:Perch?

[crtreece]

I am interested in your newsletter and would like to subscribe.

Re:Perch?

[Tubal-Cain]

OK, think "helicopter". I'm pretty sure he means the propeller can provide enough thrust to lift the plane straight up (allowing it to free the hook and maybe even get some altitude before going to horizontal flight).

Re:Perch?

[Deadstick]

One would wonder how the hell our ancestors managed to survive without living in a surveillance society.

Well, if you can't come up with a better counterargument than "Homo Habilis survived without it", you're going to have a traction problem. You could argue against shitting downstream of the well with that line.

rj

Re:Perch?

[westlake]

"Religion is regarded by the common people as true, by the wise as false, and by the rulers as useful." -Seneca.

I am tempted to suggest that this is not the right approach to take as an adviser to someone as amoral and profligate as Nero.

Re:Perch?

[severoon]

Here is a quote from a part of the article that I just completely made up: Said a lead engineer on the project, "The hard part was figuring out how to wirelessly transmit payment to the power provider for the stolen energy."

Re:Perch?

[ultranova]

"The hard part was figuring out how to wirelessly transmit payment to the power provider for the stolen energy."

Simply charge it on the people being surveyed (you are using face recognition technology, right?). If they weren't such suspicious characters, always complaining and plotting against their clearly deserving masters, this kind of thing would be completely unnecessary. But the price of freedom is eternal vigilance.

Re:Perch?

[MichaelSmith]

My guess is they would do a bulk deal, probably for a token amount to make sure it is legal. Power bills for street lights and traffic signals work that way in my state.

Re:Perch?

[SanityInAnarchy]

Making a broad assumption as to the beliefs of an entire religion on one very loud extremist nutjob

Ah, the "no true Scotsman" fallacy.

Falwell's church claims 24,000 members, and it's far from unique.

Of course, you didn't respond at all to "various Protest Fundamentalist theologies" at all...

Re:Perch?

[SanityInAnarchy]

transcendental God of the Bible

The God of the Bible was, at least once upon a time, a storm god -- so very much a sky-god. His son (who is also himself) was supposedly very physical, really here (at least according to some accounts -- others aren't sure the crucifixion happened on this plane at all).

I would guess the "transcendental" understanding has far less to do with the text of the Bible, and far more to do with our increasing understanding of the world. Until we understood what the sky was, it would certainly make sense for a god to be there -- the Bible indeed talks about firmament above and below, surely a good place for a god to live.

Do you have any particular verses you'd like to bring up that hint at him being "transcendental"?

They did not believe that some old man in the sky was coming up with clever ways for them to watch their neighbors all the time.

So it's alright for exactly one person (being, entity) to watch people, but no one else?

Why?

Re:Perch?

[causality]

I was careful to specify a "corporeal" being who levitates in Earth's atmosphere. Don't let that halt your condemnation though. I've read the Bible and it quite plainly teaches that God is spirit, is omnipresent, and has other qualities not compatible with having a corporeal (and thus physical/material) existence. The Bible argues for a transcendental God, one who exists beyond creation.

The idea of an old man with a long beard who sits up in the clouds someplace might be a way to simplify the concept for a small child. It is not serious theology.

Also, I'm very much aware of Catholic belief. I also know what the letters on the cookie taken during Communion actually represent and where they came from (hint: ancient Egypt). Also, since you feel free to assume since it helps you to get on your high horse, when I say "our ancestors" I am referring to the USA's Founding Fathers. They were manifestly not Catholic. Many Protestents wouldn't like their beliefs either, as they tended towards Deist philosophy. You could have asked me what I meant by that ("whose ancestors?") but that would be the sort of calm dispassionate discourse that wouldn't help your rant now would it?

I'll show how fundamentally absurd your little rant there is. You said that one man, Jerry Falwell, talked about the establishment of the Kingdom of God after Armageddon as "moving his headquarters from planet Heaven to planet Earth". Right there you admit that per your reference, Falwell, God is not currently occupying planet Earth, unless of course you are prepared to argue that Falwell viewed Armageddon as a past event and not a future event, which is manifestly false. Like most Baptists, and most Christians for that matter, he believed that the book of Revelation is a book of prophecy concerning future events.

I'll parody your closing line: so please, before you reply to my post, inform yourself as to what my post does and does not say. That way you won't embarass yourself quite so much with the way getting on your high horse can override your basic reading comprehension abilities.

Like I said, I know of no serious Christian who seriously believes that God is an old man in Earth's skies. If Christians did go around claiming that, a few satellite photos would destroy their entire religion. Really now, I can't believe you think this is a point of debate. Why not just come out and say "they believe in a religion in which I do not believe, therefore they're all idiots"?

Maybe you like to belittle religious people and use the "man in the clouds" routine in order to do so. I have heard many an atheist use such terms in order to trivialize monotheistic religions. It's a shame that some people (not all people and not all atheists either) would rather not study and understand a thing before deciding whether to be for or against it. At any rate, perhaps you have such venom towards me for not helping you belittle religious people.

Whatever your problem is, this is not quality debate. Whatever your beliefs are, if they are derived from degrading others then they are quite sad no matter how correct. The truth is that I have thoroughly studied most major religions and several rather obscure ones. Still, it doesn't matter much to me if you would like to judge me as knowing little about this one.

Read this part well: You clearly make this judgment of me based on the flimsiest of evidence merely because I said one thing ("juvenile") that obviously stuck in your craw. Guess what that is? That's right, it's a juvenile thing to do, for it allows emotion to override reason, just like you'd expect from a child or an angry little man who never really grew up. Want to hate me now? Go for it, but I warn you, you harm yourself by so doing.

It's a shame that so many are in the business of impressing others, so they kow-tow to this kind of personal attack and try to win back your good graces. I won't. Accuse me of ignorance, stupidity, call me names, do anything you like. What I will do is much simpler and imposes no burden on me: I'll see that you're out of order and say "hmm, that's too bad, we could have had good conversation".

Re:Perch?

[nedlohs]

Again if it can do that it doesn't need to stall, it can hover above the power line and drop.

Of course the thing in question is a glider anyway...

Re:Perch?

[davester666]

Um, why wouldn't this be considered theft of electricity? Or can anybody just attach things to power lines and take whatever they need?

Re:Perch?

[PitaBred]

They hang plates of metal off the wires where I'm from. Otherwise ice would freeze on the lines and pull them down, the plates make sure the wires move in the wind and break the ice off. It's doable, and not a completely insane idea.

Re:Perch?

[fuzzyfuzzyfungus]

No, it certainly didn't do Seneca any good.

On the other hand, given that the custom of deifying emperors had taken off by that point, trying to use religion to threaten an incipient god probably wouldn't have worked all that well either...

Re:Perch?

[Painted]

Personally, I find it very telling that you interpreted "They believed that some old man in the sky was watching them all the time." as a direct attack on Christianity.

Plus, if you honestly believe that some "serious Christians" don't functionally believe that there is a bearded old man "in the sky", you're deluding yourself. If you had said "very few" or "no informed" Christian believed it, you'd be on stronger ground.

I do hear the undertone of "Stop oppressing me!" from the Christian majority shouting out from your posts though.

Re:Perch?

[marcosdumay]

Take a second look in that page. You'll probably notice that the inducted potential is proportional to the inductance of the secondary coil. Guess what, the wiring of portable equipment is very small, and, thus has very small inductance. Nearly all of the power emanating from your EMP will go to power lines.

Unless you have a very good directional antenna on your EMP generator (better than anything you can carry on hand), you'll fry everything connected to power lines before you have any impact on the surrounding mobile equipment.

Re:Perch?

[AP31R0N]

Slashdot: News for Paranoid, cynical egomaniacs.

Re:Perch?

[Anonymous Coward]

teste

Re:Perch?

[Pingmaster]

The formula for induced voltage in a transformer is Vs = (Ns/Np)*Vp Vs is the voltage in the secondary coil, Vp the primary. Np and Ns are the number of turns of wire in the primary and secondary coils, respectively. The way a transformer works is an AC current is passed through the primary coil, creating constantly expanding and collapsing lines of flux. These lines of flux pass through the secondary coils inducing a current in them. The voltage produced as a result of the induced current is directly proportional to the ratio of the amount of turns of wire in the two coils. Not that it has nothing to do with the size of the wire, just the amount of pieces of copper passing through the flux. Often, transformers use the smallest wire possible that will still support the amount of current needed.

A cell phone with a 1GHz processor has hundreds of thousands, if not millions or more tiny copper conductors. If a line of flux crosses all of them, then they will each induce a potentially damaging current, especially considering that an increase of 1-2V will create sufficient current to severely damage most handheld electronics. A power transmission line is effectively one conductor (it may be a stranded conductor, but that's considered to be connected in parallel, thus the voltage is equal in all conductors, not added together) and is generally in the 3-25kVAC range before the transformer and 120-240VAC after the transformer (these are all RMS values of course, hook an oscilloscope up to a 120VAC power source and you'll see closer to 170Vp, which is 340V from absolute maximum to absolute minimum).

So let's do some math. Let's say an EMP drives a pulse of 1Wb/s, which when passing through a conductor will induce a voltage of 1V. So now the processor in the mobile device, which is used to 1V, is now randomly dealing with voltages anywhere from -1 to 2V. This can either exceed the maximum forward or reverse voltage in the transistors, thus destroying the processor. The change of 1V in the 3.3kVAC transmission line is not even noticeable in the background noise.
Increase that pulse to 100Wb/s, now you're creating 100V in each conductor (note, I'm not considering losses due to distance, let's assume you're the strength is measured at the location not the source). The mobile device, due to the density of the wiring, may start arcing between traces, maybe even give whoever is holding it a bit of a shock. The extra 100V may be enough to pop your household breaker, maybe a couple fuses in your more sensitive electronics but I bet your stove and fridge will still work. The 3.3kV transmission line may see a noticeable blip, but nothing out of the ordinary still.
You would need a pulse in the range of thousands of webers/second to do serious damage to power transmission systems and large household appliances, and by then, your iPhone would become a pretty crispy critter too.

Re:Perch?

[marcosdumay]

"The formula for induced voltage in a transformer is Vs = (Ns/Np)*Vp... Not[e] that it has nothing to do with the size of the wire..."

You took a simplification (that will be okay for any transformer you want to actualy make) and used it out of context. Sorry, but you are wrong.

Re:Perch?

[Anonymous Coward]

The best behavior may depend on whether the plane should be inconspicuous.

prior art?

[AntEater]

So MIT is spending how much money on reinventing the pigeon??

Re:prior art?

[radicalpi]

Is it just me, or is that Pigeon staring at us?

Re:prior art?

[jbeaupre]

They should just combine the pigeon and the roboroach. http://www.wireheading.com/roboroach/index.html

Re:prior art?

[Captain Spam]

So MIT is spending how much money on reinventing the pigeon??

I'm picturing a few pigeons on the line when this microplane perches on it. The pigeons look over at this mechanical oddity with reserved curiosity. Then an artificially-generated voice from the plane states "PAY NO ATTENTION TO ME. I AM A NORMAL PIGEON. I DEFECATE ON CARS AND THE HEADS OF PEOPLE. COO. COO". The pigeons, satisfied with the answer, go about their business.

After they fly off, the plane's voice kicks back in. "HEH HEH HEH. SUCKERS".

Re:prior art?

[Anonymous Coward]

and in the next model MIT's working on I heard they are going to fix that "caps lock" bug.

Re:prior art?

[cgenman]

This is student work we're talking about here. They're paying MIT for the opportunity to do MIT's research.

Re:prior art?

[Anonymous Coward]

Indeed.. same with those people that tried to reinvent the bird with those damn flying gizmos. No good can come of it!

What next, reinvent a better horse? FOR SHAME!

Sweet!

[WreathOfBarbs]

I for one welcome our new power line perching overlords!

Re:Sweet!

[skids]

All ur flux lines R belong TO US!

Until Elmer

[Anonymous Coward]

Fudd appears.

Yours In Moscow,
Kilgore Trout

Control System Is External

[jafiwam]

The control system is external so it has the benefit of a side-view comparison of the flight path and motion.

They'll need to come up with vertically binocular vision and a bit more computer power on board before this thing is useful.

Right now it's one part of a bigger system.

Charging

[davidwr]

"charging off transmission lines has its own problems."

Not to mention how to bill for it.

Re:Charging

[uniqueUser]

Not to mention how to bill for it.

I don't think the user will be expected to pay a bill. More likely used for military surveillance.

My question is, why does the video look like it was from the 1960's?

Re:Charging

[Anonymous Coward]

Not to mention how to bill for it.

I don't think the user will be expected to pay a bill. More likely used for military surveillance.

So the military gets to steal our precious electricity to spy on us with. Why is MIT helping them with this?

Re:Charging

[captainpanic]

Your military gets free electricity?

- What if they develop a car-based AI system that can refuel independently... free gasoline or diesel?

- What if they develop a drone that can feed off sugars, and empty's your kitchen every day? No worries?

Not that I really care - I'm just curious where you draw the line :-)

-- It's useless for any offensive purposes because the first infrastructure that gets bombed is the electricity grid. Must be only for spying at home then.

Re:Charging

[rah1420]

This brings back memories of when I was a kid. I and my friend had a 'fort' which was coincidentally under one of those "high tension" (what, about 50KV?) power lines.

We had the bright idea that rather than run an extension cord out from his house, we could just shoot an arrow that had a conductor attached to it over the lowest of those power lines, then use a transformer to step it down to the right voltage, and Bob's your uncle; instant television in the old fort.

Fortunately, we were much more interested in the architecture than the elctrical provisioning of said fort and quickly realized how in over our heads we'd be to try something like that.

Re:Charging

[danlip]

Your military gets free electricity?

They get whatever they want, because they have guns.
Although expecting the electrical grid to be up during an
invasion seems like a bad assumption.

Re:Charging

[snl2587]

At least they're not stealing our precious bodily fluids.

Re:Charging

[sexconker]

What if they develop a drone that can feed off sugars, and empty's your kitchen every day? No worries?

3rd Amendment

Or, if you're smart, simply load your car up with sugar the next time a sugar truck crashes and spills its white gold.
Dump it in your back yard to attract the drones, and then sell them back to the drone keepers at a huge profit.
Watch out for British guys trying to sweeten their tea, and watch out for rain.

Re:Charging

[jeffmeden]

- What if they develop a drone that can feed off sugars, and empty's your kitchen every day? No worries?

I would feed a spy drone some sugar if it kept the terrorists away... gotta keep the terrorists away. that's how they get ya...

Re:Charging

[uniqueUser]

Not to mention how to bill for it

I don't think the user will be expected to pay a bill. More likely used for military surveillance.

Your military gets free electricity?

The military of my country? Yes, I would assume so. I don't think an invading force will usually set up an account with the local utility company before beginning a military campaign. Could be wrong though. I personally have never planed a war, but if I did, I don't think I would expect to pay for the electricity my spy MAVs used. Just seems silly when looking at the big picture.

Do you really think the civilian use for this would out weigh the military use?

Re:Charging

[uniqueUser]

Although expecting the electrical grid to be up during an invasion seems like a bad assumption.

In Iraq, some utilities where kept as whole as possible so that they could be used during the invasion. Same thing as hoping there is still a bridge over the river by the time you get there. But, yes, I agree. The ones with the guns tend to have the advantage over the ones who are not as well armed.

Re:Charging

[Anonymous Coward]

Something like this?
Man steals electricity with meat hook

(Reuters) - German police are investigating a man for theft after he siphoned electricity off a high-voltage overhead transmission line for one month with the help of an ordinary meat hook, authorities said on Tuesday.

Re:Charging

[DavidJSimpson]

The next step is to have this little airplane carry a small rechargeable battery from my house to the power line. It would charge itself and the battery, then return the battery to my house and pick up the next battery that needs recharging. Obviously I would need to make some kind of coconut battery holder so that the plane could grip it by the husk.

Re:Charging

[zmollusc]

Would one airplane be enough to carry the coconut?

Re:Charging

[Cwix]

Simpsons right?

Re:Charging

[Anonymous Coward]

Better hope its a low charge. The power company can see unbilled usage at the plant, and are able to sense demand on the lines. I know of two cases here in Colorado where people were getting free power because of where the lines were adapted. One got fined, the other didnt, which is probably because of how he had it set up. The first actually set up a fairly fancy induction relay to power his house (and was fined for "stealing" power that was leaking out of the lines anyways), where the other just put florescent lights in his barn that lit up because of the field.

When asked to take his lights down, he said no, and that they could move their lines if they didnt want him to use it. They did route it over his barn (a pre-existing structure).

Re:Charging

[Anonymous Coward]

Well, it's mostly a question of weight ratios. For example, a five ounce airplane could not carry a one pound coconut.

Re:Charging

[Anonymous Coward]

This man is obviously a psychotic.

Re:Charging

[DavidJSimpson]

That depends. Is it an African or European airplane?

Re:Charging

[shmlco]

I don't know, but when it's attached to the airplane it is in fact migratory...

Re:Charging

[kalirion]

Wait a second, how does the company "see unbilled usage" if the power is "leaking out anyway"?

Re:Charging

[rubycodez]

news for you, placing inductor with coil near line doesn't "steal power that was leaking out of the lines anyway", it acts as secondary of transformer that in fact removes energy from line, stealing power that would have gone to customers.

Re:Charging

[Anonymous Coward]

We would all pay for it in the end.

Re:Charging

[Anonymous Coward]

Not to mention how to bill for it.

In places where such surveillance is necessary, the US is providing financing to build power plants so I don't think this is much of an issue.

The WSJ recently reported on the Taliban being a beneficiary of a American-taxpayer-financed power plant built in south Afghanistan. Perhaps such devices could make the Taliban controlled cities receiving this power a bit easier to fly into.

Re:Charging

[Anonymous Coward]

It's not stealing. They pay for the electricity with your tax dollars. MIT probably gets a cut.

Re:Charging

[Anonymous Coward]

It could be quite useful for advance recon - scout out the area before you take out the power. Not overly useful in Afghanistan as their lack of infrastructure is part of why rebuilding/consolidating control there is so hard. Having a few of these "bats" in Moscow or Beijing though, that would be handy.

Re:Charging

[Anonymous Coward]

http://www.wired.com/gadgetlab/2010/06/military-bat-hook-sucks-free-power-from-overhead-lines/

RAPS (Remote Auxiliary Power System) allows the military to steal power from overhead lines easily. They have the big guns. Who cares about the billing?

Re:Charging

[Anonymous Coward]

I don't know, but when it's attached to the airplane it is in fact migratory...

I think you mean

I don't know AIEEEEEEEEEeeeeeeeee*shriek continuing in the distance*

There, fixed that for you.

Re:Charging

[minorproblem]

Also if it flies between the lines its wingspan could potentially cause a flashover..

Re:Charging

[alonsoac]

- What if they develop a drone that can feed off sugars, and empty's your kitchen every day? No worries?

I would feed a spy drone some sugar if it kept the terrorists away... gotta keep the terrorists away. that's how they get ya...

If I have to give my sweet away maybe the terrorists have already won?

As someone on Facebook mentioned...

[magsol]

"Pooping on cars is the next hurdle."

Re:As someone on Facebook mentioned...

[troll8901]

Mod insightful.

That would require acquiring input regularly, processing said input, locating above-mentioned target, etc...

Re:As someone on Facebook mentioned...

[Crudely_Indecent]

Remember, this is a potential domestic spying device.

It's more likely they'll be pooping on our liberties.

Re:As someone on Facebook mentioned...

[HTH NE1]

Laserbeak, eject. Operation: wiretapping.

Re:As someone on Facebook mentioned...

[cgenman]

All of the powerline powering systems I've seen breach the outer shell of the line with a metal hook.

There is no way in hell that's getting approved for domestic usage. A: it would be sued out of existence amazingly quickly, and B: there are enough government-owned places around domestically that you could just plug the things in.

Further, you'd have to either have someone watch all of that video (and we're tremendously backed up on audio recordings as-is), or process it somehow in a searchable format. Something like this would make sense to replace human tails in certain circumstances, and could be helpful in backing up helicopters in pursuit cases. But overall, there aren't enough police for a full police state. We just have way too much data as-is.

Re:As someone on Facebook mentioned...

[Crudely_Indecent]

Buried lines are heavily insulated, but overhead lines are not.

Since overhead transmission lines are uninsulated, design of these lines requires minimum clearances to be observed to maintain safety.

http://en.wikipedia.org/wiki/Electric_power_transmission#Overhead_transmission

Re:As someone on Facebook mentioned...

[Crudely_Indecent]

As far as the surveillance aspect, they don't need to watch all of the video in order for it to be useful.

They just need enough video on file so they can find a violation if they need for you to go away.

Nobody ever said anything about video anyway. Devices this small could be useful in pinpointing individuals after cell tower triangulation has provided a general location. They might be useful in following chemical trails. The possibilities go on and on: Targeting beacons, explosive/chemical/bio warfare delivery, wireless signal jammers, more and more!

Microplane?

[Bovius]

Why would you need to recharge a microplane? And why would you want to use a powerline? I just use mine for lemon zest.

Re:Microplane?

[sexconker]

Why would you need to recharge a microplane? And why would you want to use a powerline? I just use mine for lemon zest.

I use mine for making furniture for doll houses.

Thanks for the "news"

[Anonymous Coward]

But this was already covered on hack a day almost a month ago

Good job guys

How does is charge from just 1 line?

[Anonymous Coward]

Wouldn't the power just flow through the line, because there's greater resistance through the glider? That's why birds don't get electrocuted when they land on power lines, right?

Re:How does is charge from just 1 line?

[Anonymous Coward]

Wouldn't the power just flow through the line, because there's greater resistance through the glider? That's why birds don't get electrocuted when they land on power lines, right?

No. They don't get electrocuted because they are not grounded.

However, that's irrelevant. I'm sure they're charging it by induction. The current flowing through the wire creates a magnetic field. In turn, you can use that magnetic field to induce a current.

Re:How does is charge from just 1 line?

[Psychofreak]

Has to be induction. You can build half a transformer (coil of wire) and get a measurable voltage, and almost usable current from standing under a high tension wire. No trespassing involved.

Now getting the device in place, doing surveillance, and getting the device removed before it is noticed would be a challenge.

Phil

Re:How does is charge from just 1 line?

[Anonymous Coward]

Ostriches are grounded. Guess that's why you don't see them sitting on power lines. Or penguins for that matter, although they do occasionally perch on the television.

Re:How does is charge from just 1 line?

[Ungrounded Lightning]

Induction couples to the magnetic field from the current through the wire.

You can also couple to the electric field emerging from the wire and extending toward the other wires, the ground, and surrounding space in general.

Both are inverse-first-power (because the wire is a line/cylinder - approximately "infinite" at the scale of the device - rather than a point/sphere).

Coupling to the mag field requires current to be flowing. Even if there is no load on the line there will be some reactive current flowing to transformers downstream, and if you're just coupling to the current you don't care if you're in-phase with the voltage or not. (You'll shift the phase to induce a little extra resistive loss in the line due to the power you pull with your coupling.) If the "feet" of the "bird" gripping the wire are a cylinder of transformer core material you'll couple very strongly.

Coupling to the electrical field can also be done because the field is very strong near the wire so the "body" of the "bird" is at a significantly different voltage than its "feet". This will drive a current through the "legs" if there is a load connected between the feet and body. The current will be limited by the capacitance of the body to the local ground.

Weight?

[Reilaos]

How large can a glider be before you would have to worry about breaking power lines?

What is it like to detach from the line and start flight back up? I can't imagine it being too smooth a process, what with starting out by pointing straight up.

How does it create a closed circuit?

[Anonymous Coward]

Seems like only contacting one of the conductors would give it about as much juice as it gives 'normal' birds.

Re:How does it create a closed circuit?

[wiredlogic]

Most transmission lines carry AC. The magnetic field generated by the current can be inductively coupled to draw off usable energy. This won't work for a DC transmission line though.

Re:How does it create a closed circuit?

[daid303]

Grab 2 points on the same line, the resistance on the transmission line should generate something to work with.

Re:How does it create a closed circuit?

[Anonymous Coward]

Most transmission lines carry AC. The magnetic field generated by the current can be inductively coupled to draw off usable energy. This won't work for a DC transmission line though.

And even if they do find a DC-line somewhere, they can just rotate the transformer on the plane - output will be greater than power needed to rotate transformer.

There's always a catch ...

[Wrath0fb0b]

From TFA:

"The heart of the system is a library of trajectories," says Tedrake. "Wall-mounted cameras report on the glider's position and the control system looks up a trajectory that will take it to the perch." [emph added]

It is very difficult for a glider to accurately figure out the distance to an approaching power line for fairly obvious reasons -- the arc subtended doesn't increase all that much as you approach until you are right up on top of it. You can use multiple cameras but that only nets you a resolution bonus proportional to the inverse of the vertical distance between the cameras. Using cameras external to the glider is an obvious improvement but it does sort of negate the idea that this is an independent flying system.

That said, I don't mean to discount the achievement by pointing out the limitation of having an external camera. Technology progresses incrementally and all that.

Re:There's always a catch ...

[asukasoryu]

As you said, external cameras seem like a good place to start. Since it's MIT, I'm sure they could afford one of those laser distance sensors which would give them distance and angle, though they might have to add an engine to handle the weight. Worst case, ultrasonic sensors would work for distance measurement (works for bats) since there shouldn't be too many obstacles when you're looking at a power line. Maybe video for determining approach angle. Seems doable.

Re:There's always a catch ...

[Belial6]

Or they could just drag a line with a hook on it.

Re:There's always a catch ...

[Anonymous Coward]

I guess they'll have to fly in pairs. One spots while the other lands.

Yes, but...

[davidwr]

If you did all of that, would that affect the charging of the plane from the power line?

I thought not....

Oops, someone just handed me a card. *reads card* "Do not feed the trolls". Sorry, my bad.

Good news!

[ThePangolino]

Now I know what to do in case I don't pay my electricity bill. \o/

Birds are smarter than nerds!

[cpotoso]

Birds are smarter than nerds!

Flock of birds?

[betterunixthanunix]

Hm...a flock of birds that performs surveillance...where have I heard that one before...

Easy to Do

[sexconker]

Landing on a power line is fucking easy to do.
Go look at some power lines.
Do you see any things that have landed on it?

I bet you fucking do.

parasites

[danlip]

I am imagining self-reproducing bird sized electricity suckers overwhelming the grid. It would make a great premise for a sci-fi movie.

Re:parasites

[Rogerborg]

SyFy are already all over it: Cyberdactyls versus Mega Werevampire.

Kristy Swanson, let's get your career going again.

Why does it perch?

[vadim_t]

It's possible to get useful amounts of power by simply placing a coil of wire under the line, and getting power by induction. On the ground it would need a big coil, but a plane could fly along the powerline and get much better efficiency. So why perch on it?

Also, where does the plane get its ground?

Re:Why does it perch?

[Crudely_Indecent]

neither alternating current or Induction require a ground.

AC becomes safer for saltwater sacks (us) if a ground is used, but we're talking about robot spy birds here.

Re:Why does it perch?

[Anonymous Coward]

How is it you have knowledge of induction but still think a ground is needed? And with induction, you have to be very close to the conductor for efficiency reasons. Flying close to a power line (with wind) is not easy. Hanging from a powerline and recharging is more practical.

where is the outrage?

[frovingslosh]

So, making a copy of a song is piracy and stealing, but taking energy from a power line is clever and innovative? Seems like very selective morality for what Slashdot condemns and what they find worthy of reporting without criticism.

Re:where is the outrage?

[tsalmark]

This may come as a surprise but Slashdot is a collection of Individuals, many of them capable of forming and holding their own opinions.

Re:where is the outrage?

[John Hasler]

> So, making a copy of a song is piracy and stealing...

No. Copyright infringement is not theft.

> ...but taking energy from a power line is clever and innovative? Seems like
> very selective morality for what Slashdot condemns and what they find
> worthy of reporting without criticism.

"Clever" is not a moral judgement (not to mention that the bit about recharging from powerlines is wild speculation imported from another article about another project run by a different organization).

Re:where is the outrage?

[Anonymous Coward]

WRONG! Slashdot is a collective! You just haven't been assimilated yet...

Re:where is the outrage?

[GrumblyStuff]

Say wah?

I'm pretty sure that 1) the majority of /.ers certainly don't view copying songs as piracy or stealing and 2) that developing a RC plane that recharges on power lines can be considered clever and innovative but is still stealing power.

You know, just the same way that movie bank robbers can be clever but they're still just thieves.

Re:where is the outrage?

[Anomalyst]

many of them capable of forming and holding their own opinions.

Speak for yourself, you insensitive clod. - A. Lemming

Starglider flashbacks

[JacksonG]

I'm having flashbacks to playing Starglider! Recharging via powerlines was one of the hardest things I found to do.

J

Who pays for the electricity?

[junglebeast]

Great, robotic birds land on the power lines and run up your electric bill.

Re:Who pays for the electricity?

[HTH NE1]

Generally there are not exposed power lines between your power meter and your home, and even less likely with newer construction. They could trace it to your neighborhood, but not to any one particular home unless they caught it perching.

There are also people working on leeching power from WiFi radio signals in order to recharge cell phones, with the consequence of reducing the range of your WiFi.

I'm looking forward to someone coming up with the not-so-bright idea of recharging electric cars using the induction loops that control the lights at intersections. Like pulling power for your time machine by parking on a rift in Cardiff.

Re:Who pays for the electricity?

[John Hasler]

> There are also people working on leeching power from WiFi radio signals in
> order to recharge cell phones, with the consequence of reducing the range of
> your WiFi.

That would not reduce the range of your WiFi: the rf would be absobed by the body of the cellphone user anyway (but even if it weren't, so what? If you don't want me to absorb your radiation and put it to use don't spray it at me).

Re:Who pays for the electricity?

[evilviper]

There are also people working on leeching power from WiFi radio signals in order to recharge cell phones, with the consequence of reducing the range of your WiFi.

RF DOES NOT WORK THAT WAY!

When you wear black clothes and stand in front of a spotlight, does the light start to bend towards you? Does the amount of light going in other directions get reduced by any particular amount?

Of course not. And so it is with RF. At WORST, the only thing you can do is create a very narrow "dark spot" if you are directly between the source and destination. At BEST, you're merely turning into electricity what would otherwise naturally turn to HEAT as it is absorbed by your body.

Re:Who pays for the electricity?

[JesseMcDonald]

That would not reduce the range of your WiFi: the rf would be absobed by the body of the cellphone user anyway ...

The problem is that they wouldn't just be absorbing the radiation. Well, I suppose they could just absorb the signal (and generate a minuscule amount of power from the resulting heat), but it wouldn't be very practical. When you collect power from EM radiation via induction, whether the source be high-tension power lines or a WiFi hotspot, the induced power creates an inverse transmission that partially cancels out the original field around the receiver. In the case of WiFi the result would look a lot like multipath interference. In the case of power lines this backinduction places a greater load on the generators, just as if a normally-connected household had turned on additional appliances. The more efficient the inductive connection is, the greater the apparent load.

If you don't want me to absorb your radiation and put it to use don't spray it at me[.]

On this point we are agreed, but they're not really objecting to you receiving free energy so much as to your unintentional interference. If you somehow managed to simply absorb the radiated energy without sending anything back they would have no reasonable basis for complaint.

Re:Who pays for the electricity?

[Anonymous Coward]

The amount of power would be so small for an RC sized craft, I doubt they could tell- but I don't see why you couldn't pay a flat rate per vehicle?

Re:Who pays for the electricity?

[pclminion]

When you wear black clothes and stand in front of a spotlight, does the light start to bend towards you? Does the amount of light going in other directions get reduced by any particular amount?

No, but that's because incandescent light is incoherent light. With coherent light, like carefully modulated RF, a passive absorber can cause effects that are more complicated than just "casting a shadow." The radiation field is a superposition of an infinite number of waves. By absorbing some of these waves you obviously decrease the total power of the light field, but you may also cause constructive interference in some regions and destructive interference in others. And where precisely the effects occur isn't as simple as a "shadow" behind the absorber.

With incoherent light, interference does not occur (rather, it averages out over short time periods) and so these interference-related effects aren't something you see in the every day world. But modulated RF is most certainly NOT incoherent.

The stuff that's actually interesting

[Zackbass]

If anyone here is actually interested in the science behind this you should have a look at some of the lab's publications on the subject. As per Slashdot tradition, all the brilliant points brought up so far in the comments already have answers, they're just a little bit harder to find this time.

Our research group's website:
http://groups.csail.mit.edu/locomotion/index.html

On the actual perching work:
http://groups.csail.mit.edu/robotics-center/public_papers/Cory08.pdf
http://groups.csail.mit.edu/robotics-center/public_papers/Hoburg09a.pdf
http://groups.csail.mit.edu/robotics-center/public_papers/Moore09.pdf
http://groups.csail.mit.edu/robotics-center/public_papers/Roberts09.pdf

Rick's PhD thesis on the subject:
http://groups.csail.mit.edu/locomotion/perching_media/CoryThesis.pdf

and on the controls side:
http://groups.csail.mit.edu/robotics-center/public_papers/Tedrake09a.pdf

Re:The stuff that's actually interesting

[Dthief]

Do they address how well this stalling works in conditions that include wind? A bird can adjust or pull out of the stall, can these planes do this in the position they are in?

A little side note to the geniuses at MIT

[bplipschitz]

Miniature surveillance aircraft would never need to return to base if they could cling to overhead power lines to recharge their batteries. Now engineers at the Massachusetts Institute of Technology are close to perfecting the trick – taking inspiration from birds.

Uh, the birds aren't recharging.

Really.

Re:A little side note to the geniuses at MIT

[John Hasler]

> Uh, the birds aren't recharging.

A Great Snowy tried that on the 7200V line that used to run over one of my pastures. Hung there upside down for weeks.

Re:A little side note to the geniuses at MIT

[Anonymous Coward]

Uh, the birds aren't recharging.

Really.

Uh, they are.

Really.

See definition 4

Re:A little side note to the geniuses at MIT

[ap7]

Usually, sitting high up there, they are discharging!

Re:A little side note to the geniuses at MIT

[noidentity]

Uh, the birds aren't recharging.

That's what you humans thi... uhh, nevermind, yeah, we don't recharge.

Yes! Finally!

[BJ_Covert_Action]

Soundwave! Play back Laserbeak's findings!

I can die happy now.

STARGLIDER!!!!!

[pugugly]

https://secure.wikimedia.org/wikipedia/en/wiki/Starglider

Just learned about it this weekend

[Junior J. Junior III]

Steven Rambam mentioned this (and showed a cool video of it) at his "Privacy is Dead: Get Over It" talk at The Next HOPE. It's too bad there wasn't any coverage of The Next HOPE on /.

Charging through induction

[__roo]

It shouldn't be too hard to charge a small battery through induction. We already saw an example of this when Richard Box used induction for his fluorescent light art, and it's not an uncommon subject for questions on underaduate E&M exams.

Drag a little electrical contact

[Anonymous Coward]

basically like an inverted street car.

Why land at all?

Surveillance Society

[Anonymous Coward]

Thanks MIT for helping us march down the path towards a surveillance society a little more.

On the other hand I could see versions of this being used by smugglers to move a kilo or so of drugs at a time across borders or fly a few pounds of explosives into a government building. The sword cuts both ways.

Missing something

[Shimmer]

From TFA: "Wall-mounted cameras report on the glider's position and the control system looks up a trajectory that will take it to the perch."

How exactly is that going to work with an actual power line? Not a lot of wall-mounted cameras up there.

Re:Missing something

[element-o.p.]

In much the same way that ancient Chinese bottle rockets ultimately led to the Saturn V or the way that a marathon runner started by taking a few tentative steps while holding on to a coffee table around 10-12 months of age.

Most progress is not the result of someone getting a brilliant idea and immediately creating a finished product. Rather, progress is the result of incremental steps, with the first baby steps being to simplify the problem and learn the best ways of accomplishing the goal, then slowly making the problem harder until you have achieved your ultimate goal. Likewise, MIT has simplified the problem of landing on a power line by doing so under controlled conditions with wall-mounted cameras. As they gain experience, they will learn how to improve their perching algorithms until an entirely self-contained system flying in the real world is possible.

Seriously, this is /. which is *supposed* to be populated by geeks. I would think here, of all places, we would understand how science and technology progresses [:rolleyes:]

Re:Missing something

[SleazyRidr]

Seriously, this is /. which is *supposed* to be populated by geeks. I would think here, of all places, we would understand how science and technology progresses [:rolleyes:]

Why would you think that? On every story about a new technology there's at least a few comments about how it's not ready for market yet, so it's not really news.

Re:Missing something

[Will.Woodhull]

A couple of wing mounted cameras, some simple image recognition software, and range-finding by triangulation would do it. At a guess, processing 10 images a second would be easy to do, and would provide more than adequate rate-of-approach and wind-drift info. Probably do the software in Forth on silicon, which would be particularly fitting since Forth was initially developed as an optical robotic control language.

On further reflection (pun intended), add a low power, low weight pointing laser to paint a dot of light on the wire, and home in by triangulation on the dot. That would reduce the image recognition processing to a trivial exercise.

bird hunting

[Anonymous Coward]

any advise on cleaning/cooking these new birds for next time I go quail hunting?

Or this one, for the Navy Seals in the field

[way2trivial]

http://www.popsci.com/gadgets/article/2010-06/bat-hook-designed-military-engineer-lets-you-charge-your-phone-overhead-power-lines

a bat hook?

hover near lines?

[madcat2c]

I seem to remember a mythbusters episode where they just strung up some long copper line on the ground, under some high voltage lines, and collected electricity that way. Why not just have the plane land "near" the high voltage lines and collect electrons in that manner?

Another problem

[EmagGeek]

"As you can imagine, landing on a power line is hard to do ... and charging off transmission lines has its own problems."

Yeah, stealing electricity also has its problems...

Re:Another problem

[pclminion]

Yeah, stealing electricity also has its problems...

Right, because the spy agencies that would have the most use for such surveillance devices are just going to throw their plans out the window because they couldn't figure out how to pay the power company.

MIT is just developing a technology, they aren't stealing power for their computing center. Jesus.

Re:Another problem

[EmagGeek]

Spy agencies do not have the right to steal electricity, or anything else, from anybody. They will have to figure out a way to pay whichever power company provides the electricity that they use, which means a certified metering device and some honesty.

I don't think we can hold out any hope for the latter.

Like streetlights ...

[Ungrounded Lightning]

... they'll probably end up paying a flat rate per in-commission drone.

Being in that industry...

[gearloos]

I can say a few things about this. Who is going to be responsible when the things get too close and trip a CB ? If the thing doesn't explode and stays put then some damage can occur. Probably not, because the recloser would kick in and see the load then trip the line again, this time permanantly, but there could be some damage...and btw Big birds cause this all the time but usually around the racks in the substation. Second thing.. Who's going to pay for the power they are stealing? Yes stealing... I know it is from getting inside the flux field and not through direct connection but they are still stealing power. Next, There isn't anything sensitive enough to accuratly gauge how much they are stealing but none the less, the load can be seen

Re:Being in that industry...

[Renraku]

Who has to pay the bill when a squirrel shorts out two lines and fries itself?

this is the same thing right?

[xmousex]

http://tech.slashdot.org/story/07/12/20/2036228/Tiny-Morphing-Electricity-Stealing-Spy-Planes-Developed?art_pos=47

I just remembered reading about it here is all.

I've seen them

[johno.ie]

I'm pretty sure there's a couple of these nesting in one of my sheds.

Theft of power?

[wealthychef]

So if I want to steal power from a power line without paying for it, it's OK?

Easy to defeat

[listentoreason]

It's going to be trivial to defeat these. Just fire up the Giant Flying Blade of Doom and rather than picking a flight path parallel to the lines, plot a perpendicular course. Jump to 3:58 to see how MicroPlane removal would ultimately be effected.

The other advantage is that once the power-line perching Cessna is developed, the system is equally effective

Been there, done that.

[Anonymous Coward]

Some years ago, someone made a plane who could land on a wall (a model in that case, but it was a real one, not an animated movie).

BTW, Santos Dumont invented the plane. If you're going to say the Wright brothers, I'd say McCoys and Hatfields had a working prototype decades before... :-|

In the words of Han Solo,

[chaotropic agent]

Great! Mynocks. They're chewing on the power cables.

domestic surveillance

[dcraid]

A quarter of the population of the earth does not have access to electricity. http://www.iea.org/work/2005/poverty/blurb.pdf It stands to follow that much of the planet is not covered with power lines.

Clearly this technology is meant for a future war, but where are we planning to fight our next war?

poing!

[toxonix]

I think they could perch a little softer. It looks pretty clumsy at this point. Also, would they be charging by inductance from the huge EMF?