A new generation of robot cleaners that not only sweep up but also recharge themselves automatically when battery power runs low, is expected to go on sale in the Chinese market in the next five years at a cost of just 1,500 yuan (200 US dollars).

The robots, 36 centimeters long, 34 centimeters wide and 12 centimeters high, have been developed at the computer department of Harbin Industry University in Northeast China's Heilongjiang Province.

"It is a combination of a mobile robot and a vacuum cleaner. First it reconnoiters the room using infrared remote control, and then works out the best path to the area that needs cleaning," said project chief Professor Hong Bingrong.

"The robot's memory function means it can return to the charger automatically when it runs out of power."

The infrared sensor enables the robot to locate the dirt and it does not leave a mess around the furniture, Hong added.

Topnotch robots currently sell for more than 2,000 US dollars. More modest household models in the 200 US dollars price range tend to lose their way when impeded by obstacles and end up repeating work in the same place. They are not efficient, he said.

The smart robot that Hong and his colleagues have developed outperforms its competitors both in terms of price and in its capacity to avoid obstacles and select the right path by using its infrared sensor.

The fact that developers adopted simple and inexpensive materials for the robot's hardware cut the cost by nearly ten times. They are now equipping the robot with a voice recognition system so that it can follow its owner's orders.