Pretty cool, though my take is that if it's recharging just from induction it's essentially stealing the electricity... I suppose if the owners of the lines want to have autonomous drones monitor their status, that's not stealing, but if you wanted to release some little flying vampire drones of your own which could run indefinitely that way, someone might be less amused.
It's odd that people in the comments assume use without permission and stealing.
You wouldn't attempt any of this without permission, regulatory approval and insurance, unless you wanted to be sued, prosecuted and go broke if something went wrong. How do people think the real world operates exactly?
I dont know. There is definitely a flow of energy between the power line and the drone. But there is no closed circuit between them so there is no current flowing. I imagine there is a (slightly, almost not measureable) raised current in the powerline due to a lower resistance due to the parasitic voltage drop and phase shifting cause by the inductive load. So technically no current between the drone and the powerline. Although there is energy transfer.
But there are probably lots of people here that understand the laws of electromagnetism a lot better than me.
300A of current is going through the wire, at high voltage - that's the transmission current. Drone is not charging directly from that, it lacks a ground / other phase connection to directly tap into the wire voltage (also, it lacks a... power substation and a bunch of other stuff to step down and convert the high-voltage AC from the line to low-voltage DC for the battery). Instead it uses an induction charger that "leeches" off of the magnetic field of the wire. If the wire current is higher, the magnetic field is stronger, so it can pull more power than the currently possible 50W.
driving drunk is illegal as shit too, but you can't be naive enough to believe that's enough to stop people from doing that. If you had a drone and wanted to see if this worked, you'd just drive 50 miles from your house and just... try it out. The US isn't yet covered with surveillance cameras like the UK.
Bro, "it's better to ask forgiveness than permission" is a pretty common saying in business circles. A lot of enormous businesses, such as Uber or AirBnB, were founded completely on operating without permission, regulatory approval, or insurance, until those things were absolutely forced upon them, and even then they didn't always comply with the law. It's also common that companies assume they will be sued, and go ahead anyway because they know they'll make more money than they'll be sued for. And if you do get sued... there's a good chance you can just never pay up, which I'm seeing more and more often.
The real world is certainly not your optimistic "corporations won't do anything wrong because they're afraid they'll get in trouble".
You mean like Microsoft and Apple stealing intellectual property from Xerox? Or more recently, like Cambridge Analytica?
Those are the ones that you can read about on Wikipedia. There's plenty of corporate theft happening all the time that never makes it into the public eye.
I mean bro, Boeing just murdered a whistleblower. It's not like criminality is inherently a barrier for companies.
> A passively actuated gripping mechanism grasps the powerline cable during landing after which a control circuit regulates the magnetic field inside a split-core current transformer to provide sufficient holding force as well as battery recharging.
When the grippers close they probably close the loops of a coil that wraps around the wire. So it's harvesting the ever changing magnetic field that arises from AC current, independent of voltage. You can still get some power from coils that aren't wrapped around the wire but are still parallel. I think that's how wireless phone chargers work.
You can also take power using a capacitor instead of an inductor, from the changing voltage (not current) in an AC line. Like when you hold a florescent tube vertical under a hi-power line, and it lights up.
This would vaporize the drone, the wire, and anyone or anything nearby, sending flaming battery and electronics shrapnel in many directions. High tension does not mess around.
There's nothing gentle about 38kV. You're not going to lower down a line and bleed off some charge. Once there's a viable path to ground, current will flow all over whatever is making that path, including the very air around it. The entire drone, wire, and the air it is inside of will turn into vaporized plasma as if hit by a bolt of lightning. And 38kV is low voltage in the high-tension world.
Creating current flows from a field is what induction is, so if you're imagining that you could just generate electricity from a field, well, that's what they're already doing. It doesn't take lowering a probe. You can just use an inductor.
That is exactly opposite of what would keep the drone safe. In a power transmission network the earth is a conductive path. Touching a phase and touching earth allows the grid to push as much power through you as your impedance and grpund contact will allow.
If that can be measured, I would be pretty surprised.
I would project that the drain from all possible drone charging is orders of magnitude less than the e.g. coronal loss or the static radiation that blasts my ham radio.
Any legal action would need to be able to document that loss, one would think.
But you agree the loss exists, right? It's simply difficult to detect from some aggregate noisy flow at a centralized location, because the system was never designed to make that easily measurable.
The amount could be estimated by looking at how much flying the drones do between charges, or by suing for access to charging/position telemetry of the units.
If the drones could meter their own consumption from the line using a utility-approved meter, anyone with a drone with said meter should be able to just tap onto lines at will and get a bill at the end of the month.
Not sure how that plays out in terms of the weight/packaging of the drone but seems feasible for at least larger drones.
I would argue that it is less than an order of magnitude smaller than the coronal discharge or other losses.
I suspect we are talking about 24 watts as compared to eg 1000 megawatt 500kv line. This is seven orders of magnitude difference. Totally lost in the noise.
Effective immediately, all airspace below 500 feet near powerlines is now classified as Class M airspace (for money). If your registered drone is detected nearby, you’ll be charged per second.
> smaller than the coronal discharge [...] lost in the noise
This is again technically plausible but ethically irrelevant.
It's like the fallacy in: "It's OK for people to steal goods from that store, because the parent-company is very big and one theft won't even show up on their monthly financials and they've got spoilage and breakage too."
> I suspect we are talking about 24 watts
The video demonstration shows 50 watts of input.
Napkin-math: Suppose one drone uses 1000 (battery) watts flying around, and does so for 4 hours each day for a month. (Made possible by an improved version of this research that charges at 200w.) That's 4 kWH. The electrical price is $0.20/kWh.
That means siphoning $24/month for one drone. That's not a casual "keep the extra penny", that's a Netflix Premium subscription.
An alternative view, power companies point the finger at drones for outages or fires. Look the other way when people are stealing pennies. When the billion dollar bill comes in, hand it off to the police. Let them identify the operator, and put them on the hook for damages.
right now the loss does not exist. Its a cool experiment. If this was a big thing the drone fleet operators would simply get some kind of legal agreement with the transmission operator. But overall we are talking about really small amounts of energy.
> we are talking about really small amounts of energy
Napkin-math time: I see 4 motors, searching the model-number suggests each has a max draw of ~380 watts, so let's assume it averages 1000 watts in operation, for 6 hours a day, with a local cost of electricity at $0.20 per kilowatt-hour, and this continues for one month.
That's bad napkin math. Per the video, it is charging at 50W. At worst, it would be charging 24hr/day, so 50Wx24h is 1.2kWh per day. Using your 20¢ rate, that's $0.24 per day or 7.20/month. That's the upper bound, assuming it only charges and does no work.
> That's bad napkin math. Per the video, it is charging at 50W.
I previously pointed that out to someone in another comment, however I did not use 50 because the video-presentation continues with:
> The current in the power-line was approximately 300 amperes [...] a higher power-line current would result in a proportionally higher charging power. As future iterations of this system become more efficient, the ratio of time spent flying and time spent charging will significantly increase.
The point remains that once you reframe the electrical situation in financial terms, you will realize it is not just gleaning discarded ergs, and is instead significant enough to raise questions of theft and justice.
This could become a major power draw over decades. It's probably time to figure out a protocol. E.g. a cheap light small low power meter on the drone that can post the transaction to the electric company while in flight, signals to designate power lines as in or out of the system and their current price, etc. Solar roof owners could compete with the utilities. There are unicorns hiding in this forest.
The vampires will be the charging drones that aren't associated with a transaction. So it's about as enforceable as a requirement that drones have accurate identifier transponders.
If I was the power distribution owner I would not trust the drone meters. Probably would need some type of load profiling on the distribution side, then all the drone has to do is authenticate a valid customer id for billing.
> If I was the power distribution owner I would not trust the drone meters.
Understandable.
> then all the drone has to do is authenticate a valid customer id for billing
I mean you can ask for anything, but how do you police it? If the drone is by a recognisable entity doing legitimate things sure you can fine them if they don’t comply. But what do you do with literal fly-by-night operators?
How so?
There are 120,000 miles of transmission lines in the USA. Not all of that is overhead high voltage, but the system is still vast. Where do you put the net?
The problem has three prongs:
Detection: there is so much line, and much of it is away from regular eyes. Intermittent-moving threat: Imagine you get a report about a drone perching on your wires. You schedule and dispatch a team to deal with it. Most likely by the time they arrive on site the drone is gone. They are playing a catchup game with moving threats. Action: okay, you got a drone in sight. Either because it didn’t move away, or because you got lucky. What do you do? Mind you the lines are really high and poking things near them can be hazardous if not done correctly. So it is not just any Harry and Dick who can deal with the drone, you need someone trained and with the right equipment.
On the other hand, hung lines have a tendency to fall down, get tangled in trees, and start forest fires, so the cost of above ground lines is also high...
Burying those lines is not practical. Inspecting and repairing them is. The problem is significant deferred maintenance. Buried lines cost much more to maintain, in addition to installation costs even where they are feasible. It's better to make sure (1) the towers don't fall down (2) into a forest ready to ignite. That can be done, but we have to pay.
See this is the thing: people complain about the little bit of power being eaten up by drones. But if power companies really cared, they’d bury their powerlines.
This is a classic prisoner’s dilemma, and you’re advocating for both sides to hit “betray”.
Perhaps if enough drones did this, they would indeed bury the lines. But that would be strictly worse than a world in which they didn’t bury them, and drones don’t steal electricity regardless.
Theft, yes, how serious? Not very. Basically a rounding error for the power company. They likely see higher loses from things like fence lines installed near power lines.
In which case the earth itself can steal the power, in addition to making your electric bill 500 times higher from the capital cost required to bury millions of miles of transmission network.
I don't think you know how infinitesimal the amount of power would be. Assuming a Mavic Mini traveling at its maximum speed of 29 miles per hour, it could cross the continental united states in 99 hours for 36 cents worth of electricity.
Yeah, it’s easier to use lab test data from Mavic Mini 3 specs: 51 minutes flight time at 21kph [0]. The battery capacity is 28.4Wh [1]. So, 18.4/(21*51/60) = 1.6 Wh/km. Assuming US is 2800 miles (4500 km) wide, we get 7.2 kWh of energy under ideal conditions, without accounting for charging efficiency and the impact of the charging system weight on flight time.
Edit: 21kph is the optimal speed for max flight time but not for the best energy efficiency per km. Most efficient speed is somewhere between that and the top speed. But this is the right order of magnitude at least.
More likely it’ll be utility companies that want to do remote and autonomous inspection of the transmission network. It’s already a big business, but if you can run the drone the entire length of the line without relocating the base as frequently, or have no base at all and transmit data over 5G? Big wins.
Right. Drones for power line inspection are common. Far easier than inspections involving bucket trucks, helicopters, or even people on the ground with binoculars. This will simplify that process. Especially for lines through rugged country, where following the line is difficult. Start the drone where the power line crosses a road, and then drive to another road crossing for pickup.
Warning lights for aircraft which clamp onto power lines have been available for many years.[1]
Powerline inspection and maintenance are the primary use cases for this technology. And at least this particular system is in the early spinout process via https://www.ongrid.tech/
