It works thanks to capacitive sensing, in which an electrical signal passing through the object changes when touched by a conductive material, such as a human finger. Capacitive sensing is already found in smartphone touchscreens, but these devices use electrical signals at only a single frequency, whereas Touché works with a range of frequencies.
Using multiple frequencies allows the system to distinguish between a single finger, multiple fingers, a full-hand grasp and many other touch gestures. All you need is a single sensing electrode attached to the object at one end and a computer at the other, which analyses the changing signals to identify the particularly gesture in use.
The researchers say Touché could be used to create smart doorknobs that unlock when grasped in a certain way or allow tables and chairs to sense the position of people using them. It could also let you control your phone by touching your fingers together or tapping your palm. The team will present their work at the Conference on Human Factors in Computing Systems in Austin, Texas, on Monday.
Jacob Aron, New Scientist