Beam Me Up, Scotty! Acoustic Tractor Beam Now a DIY Project

Acoustic tractor beam technology is so last year. Sure, thanks to a series of coordinated breakthroughs by an international team of physicists from the UK and US tractor beams not only exist but are already being studied for practical applications in medicine and life in microgravity environments. But today, it’s all about DIY, 3D printable acoustic tractor beams that you can make at home with an online set of instructions, a 3D printer and about $70 worth of material.

A (Very) Brief Tractor Beam History

Acoustic tractor beam technology has been making waves in physics since it was first proposed by Dr. Philip Marston in 2006 at Washington State University. His work was published in The Journal of the Acoustical Society of America in an article called: “Negative acoustic radiation forces produced by Bessel beams: acoustic tractor beams and scattering.”

Dr. Marston’s fundamentals were employed in 2014 using expensive ultrasound equipment that enabled a demonstration of the sonic tractor beam. In 2015, then doctoral student at University of Navare helped develop a working proof of concept that was developed using an array of 64 loudspeakers to form a precision sequence of sound waves that could create a low-pressure area capable of trapping tiny macroscopic objects and control them in the air completely by sound waves.

Fast forward to January, 2017, now research assistant and PhD student at University of Bristol lead a team in building a functional acoustic tractor beam that can built entirely from parts fabricated by a 3D printer. Marzo’s team also created a publicly available how-to video for anyone interested in developing their own DIY handheld acoustic tractor beam at home.

Acoustics - the Revolution Behind the Tractor Beam

We’ve always known that sound can push physical objects when provided sufficient intensity - just ask the Maxell man. But to attract or pull an object has been the stuff of science fiction at least since E. E. Smith coined the term “attractor beam” in Spacehounds of IPC (1931).

Scientists have tackled the idea with varying degrees of success using everything from water to lasers and sound to manipulate tiny particles all the way up to macroscopic objects.

Portable Tractor Beam in Action

The term tractor beam brings to mind spaceships emitting mysterious beams that can control huge objects adrift in space. And as we all know, Star Trek is no stranger to the tractor beam. The USS Enterprise has used a laser variant to take care of business in space many times over the decades. Today’s technology may not be up to that level of sophistication, but in one Star Trek film, Enterprise Chief Medical Officer Dr. Bones McCoy is seen using what seems to be a portable version of sonic tractor beam technology in Star Trek 4: The Voyage Home.

Bones McCoy ST4: Voyage Home - Medical Tractor Beam?

Although the device developed by Marzo and team may only be able to move very tiny objects, the potential for medicine is gigantic. Real-world medical scientists are already studying ways to use the technology to non-invasively manipulate the insides of your body. Imagine a device, not unlike McCoy’s, using high frequency acoustics that pass harmlessly through your skin to conduct a form of sonic surgery.
 
According to researchers: “Acoustic structures shaped as tweezers, twisters, or bottles emerge as the optimum mechanisms for tractor beams or containerless transportation. Single-beam levitation could manipulate particles inside our body for applications in targeted drug delivery or acoustically controlled micro-machines that do not interfere with magnetic resonance imaging.”

Yet another technology predicted by Star Trek!

There are even more immediate uses for the 3D printable version of the tractor beam. The device can effectively levitate small objects and in doing so, mimic the effects of micro-gravity environments on microorganisms. Marzo points out that this micro-gravity research is already an area being studied by biologists.

“Recently there have been several papers about what happens if we levitate an embryo, how does it develop?” Marzo says. “Or what happens if we levitate bacteria? For instance, they discovered salmonella is three times more [virulent] when it’s levitated. Certain microorganisms react differently to microgravity.”

Future Applications

The sound-powered tractor beam as developed by Prof. Marzo has limitations for future use. Even thought it can simulate zero gravity here on Earth, it’s not presently designed for use in the vacuum of space – or anywhere where there is no air and nobody can hear you scream. Other iterations of the tractor beam that make use of light stand a better shot of fulfilling our long-term sci-fi fantasies. Light has no problem working in space. It also has no mass, but still somehow has momentum and thus has the capability to manipulate physical objects. Successful experiments in laser tractor beams have already proven capable of capturing bacteria for study under microscopes.

As a long-time science fiction fan I always assumed tractor beams would only be made of light. So, the idea of acoustics being used to manipulate objects seriously blows my mind. Both lasers and sound have been used successfully in their respective attractor experiments. So far, light is still limited to the microscopic world with fascinating potential for medical research. But it's sound that has not only pushed today’s tractor beam technology not into the macroscopic realm but made it into a low-cost DIY project. That’s a win for science I think we can all get behind.