washington scientists have developed a conductive paint that can turn any wall smart by enabling it to sense human touch and detect gestures and appliances usedresearchers at carnegie mellon university and disney research in the us found that they could transform dumb walls into smart ones at relatively low cost about usd 20 per square metre using simple tools and techniques such as a paint rollerwalls are usually the largest surface area in a room yet we dont make much use of them other than to separate spaces and perhaps hold up pictures and shelves said chris harrison assistant professor at carnegie mellonas the internet of things and ubiquitous computing become reality it is tempting to think that walls can become active parts of our living and work environments said harrisonthe researchers found that they could use conductive paint to create electrodes across the surface of a wall enabling users to place or move light switches or other controls anywhere on a wall that is most convenient or to control video games by using gesturesby monitoring activity in the room this system could adjust light levels when a tv is turned on or alert a user in another location when a laundry machine or electric kettle turns offwalls are large so we knew that whatever technique we invented for smart walls would have to be low cost said yang zhang a phd student at carnegie mellon universityresearchers wanted to make it easy to apply the special coating with simple tools and without special skillsusing painters tape they found they could create a crosshatched pattern on a wall to create a grid of diamonds which testing showed was the most effective electrode patternafter applying two coats of conductive paint with a roller they removed the tape and connected the electrodes they then finished the wall with a top coat of standard latex paint to improve durability and hide the electrodesthe electrode wall can operate in two modes capacitive sensing and electromagnetic em sensingin capacitive sensing the wall functions like any other capacitive touchpad when a person touches the wall the touch distorts the walls electrostatic field at that pointin em sensing mode the electrode can detect the distinctive electromagnetic signatures of electrical or electronic devices enabling the system to identify the devices and their locationssimilarly if a person is wearing a device that emits an em signature the system can track the location of that person zhang saidalthough the technology has not been optimised for energy consumption zhang said but he estimated the wallsized electrodes consume about as much power as a standard touch screen