Thomas Moore, Sky News:

Researchers have for the first time used a tractor beam to move a levitating object around an obstacle course.

Sky News filmed the breakthrough at the University of Bristol, where engineers were able to manoeuvre a polystyrene ball that had been suspended in mid-air by the power of sound.

The levitation technique used 256 tiny loudspeakers arranged around a laboratory test rig.

The levitation technique uses a bank of speakers to create a “tornado” of soundwaves, which lift and contain an object within a spinning wall of energy.

By switching speakers on and off in sequence the engineers were able to steer the ball with a high degree of accuracy.