Credit: Frank Wojciechowski Princeton University researchers James Sturm, Naveen Verma and Sigurd Wagner demonstrate their sensing wallpaper.

When we think of sensors, we typically conjure small, discrete pieces of technology that are attached to some larger object such as a wall, road, or an article of clothing. Increasingly, however, sensors are being embedded within various objects, and the line between the sensor and carrier object is becoming blurred.

The University of Tokyo's Light-Sensitive Concrete, for example, incorporates photodiodes and optical fibers within concrete panels, transforming the slabs into building modules that can detect varying levels of ambient light. B.lab Italia's Metal Series floor tiles make use of magnetic particles that respond to static electricity, leaving traces of human footprints.

Princeton University scientists have recently unveiled another example, in the form of sensing wallpaper. The new technology integrates super-thin radios within plastic sheets, which in turn may be applied to walls or other surfaces. The sheets may be decorated or painted—just like traditional wallpaper—without hindering the function of the radio circuitry. They are also flexible and capable of generating their own power with integrated solar cells.

"We originally built this for energy management in a smart building," said electrical engineering professor Naveen Verma in a Princeton University press release. "Temperature sensors and occupancy sensors communicate with a central management system using distributed radio arrays that are patterned on wallpaper."

Verma and his colleagues anticipate their sensing wallpaper applied to monitor structural health in bridges, pipelines, or other forms of critical infrastructure. Because the wallpaper is the sensor, it is likely to detect impending problems more effectively than traditional point-based devices. The researchers predict that several more years of research and development will be required before the technology is ready for the commercial marketplace.

Blaine Brownell, AIA, is a regularly featured columnist whose stories appear on this website each week. His views and conclusions are not necessarily those of ARCHITECT magazine nor of the American Institute of Architects.