India's top innovations

Twenty young Indian innovators have made it to the annual list of the world's 35 most outstanding innovators under 35 published by the prestigious American magazine, Technology Review. Vasanthi Hariprakash profiles five of these inventors.

SHOES THAT SEE

A shoe equipped with Le Chal

Visually impaired people suffer greatly when it comes to mobility - having to depend on someone for directions or to alert them to obstacles. Even a walking stick can only be of limited help.

So how about a shoe that can help them go places?

That was the question that inspired engineer Anirudh Sharma, 24, to develop Le Chal - Hindi for Take Me Along. It is a low-cost shoe that doubles as a navigation aid with four embedded vibrators: in the front, back and on either side.

Le Chal works via a mobile phone which has GPS (Global Positioning System) and Google Maps.

You tell your destination to the smart phone, which then uses Bluetooth to communicate with a circuit board in the heel of the shoe. The user then gets a poke in the direction to turn.

Mr Sharma is now looking for a shoemaker who will help him produce shoes, loaded with the Le Chal kit, that will cost less than 1,600 rupees ($30; £18.60) a pair.

TOXIC CHECK

How many times have you worried about toxins in your food? And what if you had a magic stick that could do a quick check for toxins before you eat or drink.

Priyanka Sharma's "plastic biochip electro-chemical sensor" may well pave the way for such easy-to-use pollutant detectors that will help monitor harmful molecules.

Priyanka Sharma and her biochip sensor

"Due to the