Flying carpet? Yes, IIT alumnus almost makes it!

An Indian Institute of Technology-Chennai (IIT) alumnus has come up with instructions on how to make a flying carpet, just like the one in Walt Disney's creation 'The Arabian Nights'.

Lakshminarayanan Mahadevan, who is associated with Harvard University in Cambridge, Massachusetts, says that his team's instructions are not based on fantasies.

Along with his colleagues at the university, Mahadevan studied the aerodynamics of a flexible, rippling sheet moving through a fluid.

Based on their study, the researchers came to the conclusion that making a carpet that would stay aloft in air may be possible.

Mahadevan says that to stay afloat in air, a sheet measuring about 10-cm-long and 0.1 mm thick would need to vibrate at about 10 hertz with amplitude of about 0.25 mm.

He, however, has made it clear that no such carpet will be able to ferry people around.

Mahadevan admits that making a heavier carpet 'fly' is not forbidden by the laws of physics, but clarifies that the engine driving the necessary vibrations would need to be very powerful for the purpose.

The researcher says what is required for making a magic carpet is to create uplift by making ripples that push against fluids like air or water. Such rippling movements create a high pressure in the gap between a horizontal sheet and the floor, if they are close to the sheet.

"As waves propagate along a flexible foil, they generate a fluid flow that leads to a pressure that lifts the foil, roughly balancing its weight," Nature magazine quoted Mahadevan as saying.

According to him, the ripples could not only lift the foil but drive it forward also, a trait required by any respectable magic carpet.

"If the waves propagate from one edge, this causes the foil to tilt ever so slightly and then move in one direction towards the edge that is slightly higher. Fluid is then squeezed from this end to the other, causing the sheet to progress like a submarine ray," Mahadevan said.

He further said that for travelling at speed, the carpet would have to undulate in big ripples, comparable to the size of the carpet. This would make the ride very bumpy he added.

"If you want a smooth ride, you can generate a lot of small ripples. But you'll be slower," Mahadevan said.

Tom Witten, a physicist at the University of Chicago in Illinois, says that he has been fascinated by Mahadevan and his colleagues' idea to study such an unusual engineering feat.

"It's cute, it's charming," he says.