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It's not a bird or a plane: it's an unusual flying object that
propels itself by flipping inside out. Created by engineers at Festo in
Esslingen, Germany, the floating band filled with helium takes on different
shapes while expanding and contracting to generate thrust and move through the
air.

The design is based on the inverted cube shape discovered by inventor and
mathematician Paul Schatz. By dissecting a cube into three parts, two
star-shaped units can be produced at either end with an invertible belt in the
middle section which is the same shape as the flying band. The system reproduces
the entire structure: it opens to release the band while the ends remain on the
ground as a docking station.

The flying object itself is made up of six identical prisms filled with helium,
held together by a carbon-fibre framework. Three motors drive the motion
coordinated by a tiny onboard computer, pre-programmed to replicate the
inversion sequence. Using a smartphone, a person on the ground can guide the
object around a room, which will be demonstrated on Monday at a trade show in
Hanover, Germany.

Thanks to Jim Rooney