Everyone perceives warmth or coldness a bit differently; for proof, just stroll through any cubicle farm and note that while one person is wrapped in a blanket, someone a few doors down is loosening his tie and holding a tiny fan to cool down. Wearable technology
may be part of the solution to that problem.
A team of four engineering students at MIT
developed a thermoelectric bracelet that’s powered by a lithium polymer battery and is designed to keep individual wearers at their preferred temperature. The device monitors both skin and air temperature and sends small pulses of warm or cool waveforms to keep the wearer feeling comfortable.
How effective could such a technology possibly be? The team found that a change of 0.1 degree C could make someone feel several degrees warmer or colder, and their prototype can hit a rate change of 0.4 degrees C. You don’t have to be an engineering student to do the math on that.
Here’s something fun for the hardware geeks: The automated control system that determines the intensity and duration of the pulses makes use of a heatsink
--an actual copper alloy heatsink.
The team’s goals, however, go beyond simple physical comfort. “What we developed is a wearable, wrist-based technology that leverages human sensitivity, can detect and perfect rates of change, and can maintain overall thermal comfort while reducing the need to heat and cool buildings,” said Sam Shames, a materials science senior on the team. The idea is that buildings themselves can be far more energy efficient if individuals are cooling or warming themselves instead of relying too heavily on facility-wide heating and cooling.
Shames and his colleagues took home the $10,000 first prize at MIT’s Making And Designing Materials Engineering Competition (MADMEC) for their work.