New Sensor Could Run Almost Perpetually

Scientists have recently created a new type of sensor, one that is capable of working almost around the clock. The device could enable a wide array of new medical implants that could be used in situations where conventional sensors are too large, bulky, or have insufficient battery life. This particular machine is very small, measuring just 2.5 millimeters by 3.5 millimeters by 1 millimeter. The package contains three basic components, in the form of solar cells, a battery and a processor. As long as a decent exposure to light is ensured – even if it's indoor – the instrument will continue to work indefinitely. Its only limitation is the physical battery wear, but modern batteries last for years, LiveScience reports.

“It could vastly improve the efficiency and cost of current environmental sensor networks designed to detect movement or track air and water quality,” the creators of the sensor explain in a statement. In addition to this use, it could also be employed in studying the structural integrity of bridges, homes and office buildings. Its small size and long battery life enables engineers to use this sensor in ways that have never before been thought possible with similar electronics. The machine apparently uses about 2,000 times less electrical energy in sleep-mode than any of its competitors.

“Our system can run nearly perpetually if periodically exposed to reasonable lighting conditions, even indoors. Its only limiting factor is battery wear-out, but the battery would last many years,” Electrical and Computer Engineering Professor David Blaauw adds. The way the new instrument works is by spending most of its time in sleep mode. It then briefly “wakes up” for a few minutes, takes the necessary measurements, and returns back to its slumber. Overall, this ensures that it only consumes one billionth of a watt (one nanowatt) of electricity during operation.

In addition to the aforementioned applications, the scientists behind the sensor believe that it could also be used as an energy source, in the sense that it could be implanted in the body to harvest the energy of motion, or that of heat. When implanted in specific areas, it could monitor the pressure building up inside the head following a patient's violent head trauma. It could also keep an eye out for tumors in people with glaucoma, or those suffering from cancer. The work was funded by the National Institute of Standards and Technology (NIST), the National Science Foundation (NSF), and the Defense Advanced Research Projects Agency (DARPA).