The Pentagon wants to track soldiers' heart rates with tattoos

In the Pentagon's ongoing quest put a finger on the precise causes and effects of combat fatigue, the Defense Advanced Research Projects Agency (Darpa) is doing their best Q impression. This time, they're trying to figure out a way to get tattoos to record the vitals of U.S. troops during combat training and military scenarios.

Darpa, the same guys who are working on robot ostriches, battlefield illusions and a texting spy camera, recently requested research proposals to develop the next generation of bio-statistic devices. The solicitation, which opened last month, hopes new technologies can transcend the current paradigm of patient monitoring of needles, gels and electrodes. And advanced materials make it possible to integrate everything from the sensors to the transmitter into thumb-sized membranes that can stick to skin — like temporary tattoos.

Wired has the full scoop on Darpa's heart rate tattoo initiative. Oh, and they've also got the details on the use of underwear that turns body heat into battery power.

Another new technology also shows promise. Power Felt, the underwear that turns body heat into battery life, can harvest miles worth of transmission wattage. The fabric, invented in David Carroll’s materials lab at Wake Forest University, even passed an inadvertent swim test when Carroll’s wife accidentally put one of the shirts through the wash.

Welcome to the future. Where we're going, we don't need iPhone chargers AND Hanes. [Wired]