Finally our childhood dreams of a working tractor beam are coming to fruition! It’s called acoustic levitation and it actually uses highly concentrated sound waves to float small objects by essentially creating an acoustic force field.
The concept is nothing new, in fact we first covered it back in 2014 — but since then they’ve made leaps and bounds in their research. Back then they could just levitate dust. Now we’re moving onto small objects, like googly-eyes! It’s perceivable that with powerful enough speakers, larger objects will soon be harnessed…
The researchers have discovered three optimum acoustic traps which allow for manipulating objects in space with nothing more than sound. If you could see sound, the array of speakers work together to create what would look like a hologram — which is the acoustic trap. The shapes they have found to work best include a tweezer-like shape, a twister-like vortex, and now a bottle shaped trap — however only the tweezers and twister have been observed experimentally, take a look:
http://www.youtube.com/watch?v=s5r2nmvxA4s
[via Gizmodo]
OK, I don’t have a degree in physics but, there was a comment by one of the researchers stating this technology could be used by astronauts to manipulate objects in space. Hmmm…. sound based technology…. vacuum of space… Am I wrong or is this not really a workable approach for space based tractor beams?
You may be on to something here…
It MAY be, if the beam emitters couple with the release of some gas, and the sound waves can actually shape said gas…
Who said it had to be sound? It’s all just a matter of interfering waves, so the same thing could be done with light, radio waves, etc.. anything that creates force gradients around the object.
Sound waves are pressure waves: you’re literally transmitting *force* using air as a medium. Anything inside that medium can feel that force. Electromagnetic waves are exactly that: propagating electric/magnetic fields, with the electric/magnetic fields both oscillating. You can shape the oscillations, but you wouldn’t be able to shape the overall force the same way.
Plus, If you had enough photons to create a measurable force, you’d probably vaporize your target anyways.
Actually, photons work just fine:
https://en.wikipedia.org/wiki/Optical_tweezers
I was actually referring to the optical tweezer effect mentioned below.
Are you familiar with the concept of the Solar Sail project? The idea was to use the light pressure from the sun to propel a space craft. Of course, the sail has to be massive since the force from a single photon is rather small, but in theory it works just fine.
Here’s a little ‘light’ reading if you’re not convinced..
http://arxiv.org/abs/1102.4905
You are correct in that there are other methods of levitation. This is an example of acoustic levitation, other forms include electromagnetic levitation, aerodynamic levitation, electrostatic levitation, optical levitation, magnetic levitation, and superconducting magnetic levitation.
The advantage of acoustic levitation is that it is simpler to levitate objects, particularly heavy objects. Drawback is that it depends on the object being suspended in a fluid, in this case air.
Electromagnetic levitation uses an alternating electric field to induce eddy currents in an object. Because the field is always a step ahead of the eddy currents, it repels the object. This can be used to levitate certain materials at a fixed point, but generally the apparatus must surround the fixed point. Drawbacks of this method are: It works with some materials not others, It works by heating the object that is levitated. Maybe.
Aerodynamic Levitation also requires air. Nope
Electrostatic levitation is similar to acoustic levitation in that it uses interfering waves to suspend objects, BUT the object must be a material that can hold a charge, e.g. metals should work nicely; the interfering waves can be calculated to levitate a specific material of known mass, and shape; but the way that a given material will absorb, reflect, or refract those waves is radically dependent on the shape, in other words its highly unstable and damn near incalculable without perfect knowledge of the object being levitated. Since I assume we are picking up unknown objects with our tractor beam, I’m gonna say nope.
Optical levitation works to entrap micrometer scale particles inside standing light waves (with lasers) Traditionally, moving large objects with lasers is quite possible, but by the time you are lasing with enough force to move a large object, you are almost certainly vaporizing it.
Superconducting magnetic levitation and Magnetic levitation are interesting but in general it employs a two part system to accomplish the required equilibrium. I’m convinced both of these will grow significantly in our lifetime but unless you’re tractor beam is picking up magnets or superconductors you’re SOL.
I’d speculate that its possible to generate a standing electromagnetic wave that encapsulates a large unknown object at a node without being terribly destructive to the object. BUT for all the ways that we know how electromagnetic waves interact with matter, the amount of energy necessary to actually move objects especially large ones at a distance is probably more than all the energy that we are currently capable of generating on this planet.
We really just need force fields first, Somebody figure out a force field and then we can pump air into space, and then its like a billion times simpler!!!
Except that releasing gas into space would produce its own force gradient and push the object away..
I’ve watched a lot of Star Wars movies so I know that sound travels wonderfully in space. We could use this to deflect asteroids from the Earth!
In space no one can hear you scream, like a little girl.
If a cloud of gas was released in a vacuum, could sound wave be used to contain it or would they just disperse it quiker?
The astronauts speak to each other in space all the time. And they hear each other fine. They mostly operate in a pressurized environment. So while it may not work on a space walk it will certainly work in “space”.
I did a scan through the article and I didn’t see anything about space or astronauts, so I don’t know the exact wording/context you are referring to.
Perhaps they were talking about use within the space shuttle or space station while doing micro-gravity experiments?
Hoverboard using speakers? Can be used as Ghettoblaster too!
But when you put this on your Death Star in the vacuum of space….
maybe it could make a 200khz relay.
Wait a minute. This paper was so poorly written. I hope the team received an appropriately poor grade on the paper. Flawed at the very concept, my young Padawan Learners, you are. Andreas, you are on to something. I get it. I think that this is important research. I also think that they are overreaching (as many do) with the alleged applications of the technology and should really stick to the microwave repulser-lift hover-board concept. They just need to remember that to cross water, they’ve got to have power. Science Fiction, though much of it is truly hokey, really does contain some nuggets of wisdom from earlier research.
They should ask Bill Nye to help them rewrite it.
Very high power signal, with a very sophisticated modulation, for a very light and tiny target. Doesn’t look very scalable.
Instead, the best “force field” effect is still the “‘Invisible Electrostatic Wall’ at a 3M adhesive tape plant”, as reported on Bill Beaty’s site: http://amasci.com/weird/unusual/e-wall.html
“David Swenson of 3M Corporation describes an anomaly where workers encountered a strange ‘invisible wall’ in the area under a fast-moving sheet of electrically charged polypropelene film in a factory. This ‘invisible wall’ was strong enough to prevent humans from passing through. A person near this ‘wall’ was unable to turn, and so had to walk backwards to retreat from it.”
It was apparently caused by the static electricity of giant rolls of plastic in high-humidity air at the plant, but never pinned down. Unfortunately, there hasn’t been any further reference since 1990’s, which makes this dubious. Still, I’d love to see this duplicated, preferably without needing an entire scotch-tape manufacturing plant on your bill of materials.
You can start by not calling it a “tractor beam” to gain media attention.
But it is a tractor beam (which means it can pull objects toward the field emitter, which is more difficult than pressor beams that can only push).
It works by holographic manipulation of the Gor’kov potential, of course.
https://youtu.be/aP_Z3s8Zas0?t=51s
Didn’t Michael Harrison do a video about levitating styrofoam beads using ultrasonic piezos?
Controlled levitation of millions of small particles of various colors = 3D display.