IT SEEMS that fantastic floating skateboard we saw in Back to the Future and the amazing aero-cars of Blade Runner and Fifth Element may not be such a flight of fancy after all.
In what is only a small step for science, a recent breakthrough in levitation through the use of sound waves could prove to be a giant leap towards the era of the Jetsons.
It’s a long way from propelling cars or even skateboards at this stage.
But acoustic levitation has succeeded in moving and manipulating objects in “thin air”, a new study in the journal Proceedings of the National Academy of Sciences reports.
Such an ability to move substances without physical contact has immediate potential in areas such as materials processing to biochemistry – without any fantasy involved.
Most attempts at levitation until now have involved electrostatic and magnetic fields to generate the forces necessary to offset gravity. But these have proven limited to objects at the tiny micrometer scale.
The new technique creates an “acoustic field” which has proven capable in early experiments of lifting globules of water and sodium.
The method uses an emitter (essentially a specialised “speaker”) and a reflector to create a space – called a node – where the converging soundwaves cancel out gravity.
Researcher Daniele Foresti and his colleagues say their technique offers “precisely controlled motion, versatility, and a material independence that removes the need for laborious sample preparation”.
The ability to “precisely control and move these nodes provides a means to simultaneously transport and process multiple objects”, the researchers said.
Such contactless movement of materials could be useful in the transfer of DNA without fear of contamination.
And while the speakers necessary to levitate a car would probably have to be city-sized, would life really be all that different to listening to all the boom-boxes driving down your street?