Most people reach for the thermostat when the room feels hot or cold, but in fact air temperature makes up only about half of a person’s thermal comfort level. The temperatures of surrounding surfaces — cold or hot windows, walls and floors — make a significant impact on one’s comfort. “If surfaces around you are colder, then more heat radiates away from your body,” Forrest Meggers said.
The Spherical Motion Average Radiant Temperature (SMART) sensor designed by Meggers and his team is a simple, cost-effective device that can quickly and accurately measure the surface temperature at multiple locations in a room, creating a three-dimensional picture of the radiant heat and cooling sources. The information can be used to design buildings that are more energy-efficient and that don’t sacrifice personal comfort.
Until now, designers have been hampered by the lack of a low-cost, versatile sensor. The most common radiant-temperature sensor, the black-globe thermometer, measures the interior temperature of a black ball that must be moved around to different locations. Other technologies use expensive optical filters.
The SMART sensor devised by Meggers and his team consists of a rotating platform containing an infrared temperature sensor, a device for scanning the room’s surface geometry, and a microprocessor. The device can output a three-dimensional map of the hot and cold surfaces. The sensor can serve as a critical diagnostic tool for describing where additional insulation or other remedies should be placed. It can also be integrated into buildings to feed this information to a central management system in real time to save on energy costs and improve occupant comfort.
Team members Jake Read, former research specialist at Princeton and now a researcher at the Waterloo School of Architecture, Ontario; Eric Teitelbaum, graduate student in architecture at Princeton; Nicholas Houchois, staff researcher.
Development status Patent protection is pending. Princeton is seeking outside interest for further development of this technology.