Robot bloodhound tracks odours on ground

Scientists have developed a robot that can rapidly detect odours from sources on the ground, such as footprints – and could even read a message written on the ground using odours as a barcode.

Over the past two decades, researchers have tried to develop robots that rival the olfactory system of bloodhounds, which are famous for their ability to track scents over great distances.

However, most robots can only detect airborne odours, or they are painstakingly slow at performing analyses.

Researchers from Kyushu University in Japan wanted to develop a robot with a high-speed gas sensor that could rapidly track invisible odour sources on the ground.

They based their odour sensor on a technique called localised surface plasmon resonance (LSPR) that measured changes in light absorption by gold nanoparticles upon exposure to a gas.

As the robot travelled across a surface, a tube placed close to the ground suctioned odours into the LSPR sensor.

The researchers showed that the sensor could accurately detect the location of ethanol odour sources placed at different positions along the robot's path, at a travel speed of 10 cm/second (about 4 inches/second).

In addition, the robot could read the word "odour" in binary barcode deposited on the ground as a series of ethanol marks at different positions.

The robot has great potential in a multi-robot communication system or as a security robot working in an office, researchers said.