Scientists in China have demonstrated a wireless power transmission system that uses a ground-based microwave emitter to beam energy to an antenna array mounted on the aircraft’s underside. Importantly, they were able to do this while both the drone and charging system were in motion.
In tests, the car-mounted system kept fixed-wing drones in the air for up to 3.1 hours at an altitude of 15 metres (49 feet). The key challenge that the team overcame was maintaining alignment between the emitter and the drone during flight, wrote Song Liwei, the project’s leader.
Many comments are about how impractical/useless is this technology TODAY considering easier alternatives… but I see research exploring recharging electric flight devices in flight, which sounds as cool as powerful to have flight devices with larger services and ranges
I have no knowledge in this and it’s early, but what happens to birds in the medium in between the receiver and emitter?
This can’t be good for them.
Nothing. It’s non-ionizing radiation.
Microwaves ovens work by using extreme amounts of energy concentrated into a very small area.
Microwave beams for energy transmission are different.
We’ve known this since at least 1996 when the first paper talking about it was published.
https://www.sciencedirect.com/science/article/abs/pii/0038092X95000834
The biggest obstacle for it is actually RFI.
Edit to add, and here’s a NASA paper from the 1980s talking about it
I think it’s worth saying that while not ionizing, high power high gain RF can cause damage via burns. Not sure how much power/gain is used in this situation though. Staying away from unfamiliar transmitting antennas is in general a good thing.
Holy shit.
Getting the ability to remote charge things via microwave… that are moving?
That’s been basically sci fi nonsense, at a practical level, for a long time.
Anybody remember the Microwave Power stations in SimCity 2000?
If you could actually get this tech working, it has an incredible number of potential applications.
Uh…they actually got this tech working.
Will the US get this tech working? Can’t get anything working after slashing all research and kicking 10,000 phds out of the country.
Cletus and his Ram 1500 is not going to figure this out.
We’ve known about the possibility of doing this for decades.
The NRL did a practical test of it in 2022 iirc.
I remember arguing with a mate in school about the damage a misaligned beam would cause to a city. I think the prevailing theory was a lot of cooked people without much structural damage.
Except that theory has no basis in reality.
Microwave ovens work by concentrating that energy into a very small space.
When is the last time you were cooked by radio waves?
Microwaves ARE radio waves.
Assuming 1MW of transfer, and a 10m diameter beam, your looking at 12.5kW/m^2 . Not instant vaporisation, but dangerous in seconds to humans. The penetration was also mean the energy is delivered internally, where it’s harder to deal with (short term).
Any viable power transfer beam also, inherently, makes a good anti personnel weapon.
While the maths is slightly better for short range transfers, like drones, it would still definitely not be something you want hitting your body.
Are you somehow entirely unaware of the DEW crowd control devices that have been being used for like 2 decades now?
https://en.wikipedia.org/wiki/Active_Denial_System
Yeah, the whole point of these things is they basically microwave the outer layer of your skin, when in wide beam mode.
Or, they can be dialed in to be a more concentrated beam… to uh, internally heat up a bit more than just your skin.
But uh, for legal reasons of course nooo they do not do that and cannot do that.
While it is claimed not to cause burns under “ordinary use”,[50][51] it is also described as being similar to that of an incandescent light bulb being pressed against the skin,[14] which can cause severe burns in just a few seconds. The beam can be focused up to 700 meters away, and is said to penetrate thick clothing although not walls.[52] At 95 GHz, the frequency is much higher than the 2.45 GHz of a microwave oven. This frequency was chosen because it penetrates less than 1⁄64 of an inch (0.40 mm),[53] which – in most humans, except for eyelids and the thinner skin of babies – avoids the second skin layer (the dermis) where critical structures are found such as nerve endings and blood vessels.
I would imagine that if you had an emorous amount of microwave energy from an orbiting solar array, being beamed to a recieving station on earth, (ie, a very small small space compared to the distance involved) and it uh, missed, yeah, yeah it would microwave people.
There’s also this:
https://pmc.ncbi.nlm.nih.gov/articles/PMC8733248/
Brief but intense pulses of radiofrequency (RF) energy can elicit auditory sensations when absorbed in the head of an individual, an effect known as the microwave auditory or “Frey effect” after the first investigator to examine the phenomenon (1). The effect is known to arise from thermoacoustically (TA)-induced acoustic waves in the head (2).
Lin has proposed that the Frey effect may be linked to unexplained health problems reported by U.S. officers in Cuba and elsewhere, the so-called Havana syndrome (3).
Probably don’t tell any schizophrenics you may or may not know about that.
That makes no sense. It’s the wrong frequency to cook anything.
JFC…is US STEM education really this bad? Lemmy seems to struggle between STEM and Star Trek.
It’s the wrong frequency to cook anything.
The idea that microwave ovens use some specific frequency that’s good for cooking is a myth.
Dielectric heating occurs over a very broad range of frequencies. What actually matters is the energy density of the EM field. A microwave oven cooks food because its putting more than 1000 watts into a small confined space, your cellphone doesn’t because its transmitter is shooting less than 1 watt into the open air (where the energy density quickly diminishes by the square cube law).
I’m sorry, you know the precise frequency that would be used by a fictional/speculative ‘microwave’ beam emmitted from an orbiting solar array?
You… don’t think that ‘microwave’ might be technically innacurate, but broadly colloquially understood term, to describe the broad concept?
Like maybe a ‘phaser’ weapon, or a ‘lightsaber’?
Sounds:
- Pretty advanced
- Pretty expensive
- Quite useless (I mean it definitely has its uses, but I think you could find much cheaper and simpler solutions)
“… you could find much cheaper and simpler solutions…”
Heat feelt thanks for your bold show of confidence in my technical capacities. Yet I have to disclose that I’m not exactly sure to be able to compete with a first world power like China.
No, not you! I meant that guy!
Getting some Ace Combat vibes
Is paywalled for me, do they explain the range and how much power they are throwing? An altitude of 15m suggests this thing needs to be pretty close …
Sounds cool. And also like an attack vector.
Swapping out batteries in flight would probably be more efficient.
We don’t even have automated battery replacement working on the ground, while stationary.
Building aircraft with a whole bunch of their body and mass that significantly changes, in flight, is extremely expensive and difficult.
Its why the V22 Osprey is widely regarded as a death trap, why we stopped building swing wing F-14s.
… Have you ever tried to uh, remove your car’s rear seats, while on the highway, at 60 mph, and then also installed new seats, from a neaby car travelling alongside you?
Ok now do that with aircraft, at 15k feet, going 600 mph.
Yeah I’m sure that’ll be about as efficient as Elon Musk’s approach to designing the Starship+HeavyBooster.
Yeah I’m sure that’ll be about as efficient as Elon Musk’s approach to designing the Starship+HeavyBooster.
Compared to microwave energy transmission which has even worse efficiency.
Ok now do that with aircraft, at 15k feet, going 600 mph.
This is about drones. At 5 km distance and close to mach 1 you can absolutely forget any microwave based charging systems.
You are aware that we’ve been shooting drones out the sky with lasers for about a decade now, right?
Not too long ago DHS/CBP freaked out over some balloons in Texas, thought they were cartel drones, shut down the airspace, burned them outta the sky with truck mounted lasers.
JPL got 80% microwave power transmission efficiency at ~1.5 km, 8 years ago.
Granted, that was a fixed land point to fixed land point test, but also, it was 8 years ago.
I’ll take 50% efficiency loss over 10% chance of ‘everything explodes and crashes’ any day.
