Motion sensors are hardly new, but they were large, heavy and typically used in airplanes and ships for navigational purposes in recent decades. Miniaturization techniques developed as part of a relatively new field called Micro Electrical Mechanical Systems, or MEMS, have steadily reduced their size and cost.
The sensor from the University of Florida, which measures about 3 square millimeters or one-tenth of an inch, is not the smallest motion sensor ever invented. But it is extremely sensitive, draws only a tiny amount of electrical power and - most important – is one of a new generation of sensors that can be made using the computer chip manufacturing industry's standard techniques and equipment.
That means that in the near future "the application range can be expanded a lot," said Huikai Xie, a UF assistant professor of electrical and computer engineering.
In a three-year-old project they developed a single-chip sensor that can be manufactured using Complementary Metal Oxide Semiconductor technology, the industry standard for silicon chip manufacturing. The chip uses about one-thousandth of a watt of power, meaning it has the potential to operate for as long as a year on a standard watch battery. It is also extremely sensitive, so much so that it can register sound as well as motion.
Although developing the first few sensors was expensive, Xie estimated it could cost $10 or less if mass produced. He and his graduate students have installed several sensors in a cigarette pack-sized board of electronics to test their capabilities. UF also is pursuing a patent on the sensor.
"Eventually, you can wear all kinds of sensors with you to monitor everything you want to know - your heartbeat, your blood pressure or even something like your glucose concentration," Xie said. "I think this is a very interesting, exciting field that will eventually help people live much higher quality of life."