Tractor beam breakthrough could allow for levitating humans

Shawn Knight

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Engineers from the University of Bristol have successfully demonstrated the ability to trap objects larger than the wavelength of sound in an acoustic tractor beam (in not-so-scientific terms, we’re talking about levitation using sound waves).

The breakthrough could eventually lead to levitating humans although in the interim, we’re likely to see the technology used to manipulate drug capsules or micro-surgical implements within the body and perhaps even used to assemble delicate objects as part of a contactless production line.

Researchers previously believed that tractor beams were limited to levitating small objects. Testing with objects larger than the wavelength of sound proved unsuccessful as they would spin uncontrollably.

Unlike magnetic levitation, acoustic tractor beams can grab most solids and liquids.

The new technique, however, uses rapidly fluctuating acoustic vortices. Described as tornadoes of sound, these twister-like structures can be fine-tuned to stabilize the tractor beam and allow it to hold larger objects. Using ultrasonic waves at a pitch of 40kHz (similar to the pitch that bats can hear), the research team was able to hold a two-centimeter polystyrene sphere in a tractor beam. That's more than two acoustic wavelengths in size and is the largest item yet to be trapped in a tractor beam.

Dr Mihai Caleap, the senior research associate who developed the simulations, said that with more acoustic power, it will be possible to hold even larger objects. Previously, this was only thought to be possible using lower pitches which would make the experiment audible and dangerous for humans.

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Am I missing something or is there something wrong with "Objects larger than the wavelength of sound" . It just doesn't feel right to me. What do I know though
 
Am I missing something or is there something wrong with "Objects larger than the wavelength of sound" . It just doesn't feel right to me. What do I know though
I'm take a stab at it. WaveLENGTH is a measurement. Lower Freq sounds have longer wavelengths (bigger objects.) When saying "sound" just really means any particular freq. I could be wrong though I don't know ****.

I was thinking the other day about wavelengths and how light, being a wave, can travel through empty space. Soundwaves can't be heard in space because there is no medium for it to travel. But lightwaves can travel through space? I didn't look much into it but it said something about them being electromagnetic waves. still don't know ****.
 
Using sound waves can be dangerous to animals so I would recommend putting it it in outer space to deter meteorites hitting our precious earth.
 
Using sound waves can be dangerous to animals so I would recommend putting it it in outer space to deter meteorites hitting our precious earth.

Like Skjorn mentioned, sound waves can't travel through space because there's little to no medium for the to travel through. And these "Tractor beams" work via ultra high frequency sound waves, they wouldn't work in space unless you provide some way to carry them, like shooting out a jet of gas or plasma.

Besides in reality you'd only have to worry about anything as large as a small football field getting through out atmosphere.
 
P.T. Barnum was right...
If you mean, "you can click bait some of the people, all of the time, and all of the people some of the time. But you can't click bait all of the people, all of the time". That was Abraham Lincoln, not P.T. Barnum. ;):D
 
Quote by Shawn Knight: "the research team was able to hold a two-centimeter polystyrene sphere in a tractor beam. That's more than two acoustic wavelengths in size and is the largest item yet to be trapped in a tractor beam".

Well Shawn, in "not so scientific terms, "a two centimeter polystyrene ball', could possibly mean, "a 3/4" diameter Styrofoam ball". These, and perhaps much larger sizes, would burn up entering our atmosphere anyway. Besides, any potential meteorites breaking off the moon, would be made of green cheese.

Although, I certainly think that slightly larger Styrofoam balls could be used as educational tools by the Taliban, for mock stonings of young women entering puberty. This would be to illustrate what would happen if they went out in public not wearing their burka, or Allah forbid, slept around.

As an aside, I also believe Canis lupis familiaris can hear up to 40 KHz..

Plus, you could grease up the "tractor beam emitter", and use it to take pictures of babies in the womb. (You might have to diddle with the frequency a bit. I'm not sure about that).

In any event, I think the "scientists" working on this project could try to adapt it to medical applications. Perhaps even going as far as giving themselves, "ultrasonic colonoscopies" with it...(y)


Wikipedia says:
The frequency of most dog whistles is within the range of 23 to 54 kHz, so they are above the range of human hearing, although some are adjustable down into the audible range. To human ears, a dog whistle makes only a quiet hissing sound.
 
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Like Skjorn mentioned, sound waves can't travel through space because there's little to no medium for the to travel through. And these "Tractor beams" work via ultra high frequency sound waves, they wouldn't work in space unless you provide some way to carry them, like shooting out a jet of gas or plasma.
Not to mention a plasma jet would melt the Styrofoam balls you were trying to tractor in...
 
I'm take a stab at it. WaveLENGTH is a measurement. Lower Freq sounds have longer wavelengths (bigger objects.) When saying "sound" just really means any particular freq. I could be wrong though I don't know ****.
The standing wavelength of 32 Hz bass is 16 feet! That would either half or double, when going up or down in octave intervals. (An "octave" is either half or double the current frequency).

So 64 Hz would have a wavelength of 8 feet, 128 Hz 4 feet, and so forth.

This relationship is clearly mapped out with the pipe organ. The lowest "C" being 16Hz against a 32 foot pipe.
 
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If you mean, "you can click bait some of the people, all of the time, and all of the people some of the time. But you can't click bait all of the people, all of the time". That was Abraham Lincoln, not P.T. Barnum. ;):D
Barnum obscure reference was to "There's a sucker born every day"
 
Am I missing something or is there something wrong with "Objects larger than the wavelength of sound" . It just doesn't feel right to me. What do I know though
I'm take a stab at it. WaveLENGTH is a measurement. Lower Freq sounds have longer wavelengths (bigger objects.) When saying "sound" just really means any particular freq. I could be wrong though I don't know ****.

I was thinking the other day about wavelengths and how light, being a wave, can travel through empty space. Soundwaves can't be heard in space because there is no medium for it to travel. But lightwaves can travel through space? I didn't look much into it but it said something about them being electromagnetic waves. still don't know ****.


Oddly, that has never been tested, it is only a theory.

We know sound can't travel in a vacuum, but what about harmonics in space...
 
I'm take a stab at it. WaveLENGTH is a measurement. Lower Freq sounds have longer wavelengths (bigger objects.) When saying "sound" just really means any particular freq. I could be wrong though I don't know ****.

I was thinking the other day about wavelengths and how light, being a wave, can travel through empty space. Soundwaves can't be heard in space because there is no medium for it to travel. But lightwaves can travel through space? I didn't look much into it but it said something about them being electromagnetic waves. still don't know ****.
Congratulations on being a questioner and not just accepting the dogma.

Light, electromagnetism is not basically expressed as waves. It does not 'travel' through a vacuum. The 'speed' of light is simply how time relates to distance.

Sound, like light, is oscillations, repeating back and forth actions. But sound is really a secondary phenomenon. A bright explosion would be less bright underwater or in the atmosphere than it would be in space because in those pools of mass some of the energy is siphoned away as sound waves. Sound waves travel in air at about 1000 ft. per second, but the air molecules are hardly moving at all -- it's the wave front that travels. The time/distance relationship is compromised by absorption and re-release of the energy by the material medium. Light is called a wave because its seniority to the secondary phenomena makes it similar, and thus it's mistaken for the secondary phenomena.
 
@Reachable Good explanation, but I've always cherished the notion that sound waves travel by molecular collisions. That's still in keeping with your principles.

This is evinced by the fact sound travels @ Mach 3 in water, due to the much higher molecular density.
 
IN NO WAY IS THIS A "TRACTOR" BEAM. The article should be retitled as it is totally misleading.

This "discovery" is about using "sound waves for levitation".

A "tractor beam" *grabs* & *pulls* an object toward you. And using "sound" ensures it will NEVER work in the vacuum of space.

While an intriguing invention with many potential uses, "as a tractor beam" is NOT among them.
 
IN NO WAY IS THIS A "TRACTOR" BEAM. The article should be retitled as it is totally misleading.

This "discovery" is about using "sound waves for levitation".

A "tractor beam" *grabs* & *pulls* an object toward you. And using "sound" ensures it will NEVER work in the vacuum of space.

While an intriguing invention with many potential uses, "as a tractor beam" is NOT among them.
A great, but not all that difficult conclusion at which to arrive.

I'm guessing the jazz offs who performed this "breakthrough experiment", had just finished binge watching several seasons of "The Big Bang Theory", along with smoking a lid or two of weed..

I'm going to make my own "tractor beam", by placing a raw 15" subwoofer on the floor, cone facing up, toss in a few ping pong balls, and light it up with the bassiest, most obnoxious Hip-hop album I can lay my hands on. (All while wearing ear plugs, of course).

I'm not sure who made the leap from "levitating" 3/4" polystyrene balls, to lifting humans, these grant seeking toads, or our own illustrious Mr. Knight.
 
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It amazes me how tech like this is slowly coming out of the closet. Transparent tech is really slow to surface. I am in the tech world and really into it as much as I program and work in that field for many years. But come on now so what are we going to use this for in our daily life. I can see transparent tech be useful instead of having all these monitors laying around on our tables in our own make shift computer network room. Transparent tech and this would be okay but the need for it still has to be desired. Floating objects and transparent tech might go hand and hand or lifted into the air.. LOL
 
Like Skjorn mentioned, sound waves can't travel through space because there's little to no medium for the to travel through. And these "Tractor beams" work via ultra high frequency sound waves, they wouldn't work in space unless you provide some way to carry them, like shooting out a jet of gas or plasma.
Not to mention a plasma jet would melt the Styrofoam balls you were trying to tractor in...
Not necessarily, many isotopes, mostly lab made, have the ability to plasmate (is that a word?) at room temperature. I remember reading a long, boring, study some time ago about instable plasma tests. Oxygen was one I remember them using that they created plasma at room temperature. Remember plasma is simply electrification of gas.
But your point is well taken, an 99.pi accurate. Lol
 
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