Developed by Carnegie Mellon University and Disney Research, the technique called 'EM-Sense' takes advantage of the body's natural electrical conductivity to detect whether a person is touching an electrical or electromechanical device.

It is based on the distinctive electromagnetic noise emitted by such devices and automatically identifies the object.

A smartwatch equipped with EM-Sense would have a much more detailed understanding of what the user is doing than is possible with common mobile sensors, such as accelerometers or pulse monitors. The smartwatch, therefore, could automatically start a timer when the wearer begins using an electric toothbrush, unlock a keyboard without a password when users touch their laptops, or play the latest news when breakfast is being prepared.

Linking a smartwatch with a smartphone or other mobile device would expand the possibilities even further.

EM-Sense is able to differentiate between scores of objects based on the ambient electromagnetic noise they emit. The human body serves as an antenna for EM-Sense. From any body part an object touches, its distinctive electromagnetic emissions propagate through the body to an electrode worn at the wrist.

Kitchen appliances, power tools, electronic scales and door handles with electrically triggered locks are among the items that can be detected and identified.