In a recent article in New Scientist, small cheap sensors that are capable of capturing a person's movement are explored. Traditional sensors that capture motion are expensive (tens of thousands of dollars) and required lab or controlled environments. Cheap sensors that are very versatile have been developed by Rolf Adelsberger and colleagues of the Swiss Federal Institute of Technology (ETH) in Zurich, along with researchers at Massachusetts Institute of Technology (MIT), and Mitsubishi Electric Research Laboratories, both in Cambridge, Massachusetts, US. Their new motion capture sensors works even while a person is driving or skiing (see video, top right). It could make computer animation or movie effects more lifelike, the researchers say, and perhaps even help doctors analyze movements of patients going through physical therapy.
Several sensors measuring about 2.5 centimeters on each side are attached to a person's legs and arms. The sensors detect movement in two different ways: accelerometers and gyroscopes measure motion, but ultrasonic beeps are also emitted. Tiny microphones mounted on the torso pick up these beeps, allowing a laptop computer, carried in a backpack, to calculate the distance to the sensor. The system is similar to, albeit much simpler than, bats' ultrasonic echolocation, and together with the motion sensors provides a more accurate overall picture of body movement. The small backpack also holds the batteries that power the system. "The sensors are all off-the-shelf parts," Adelsberger says, making the system much cheaper than other motion-capture technology. It cost about $3,000 currently, but this could come down to a few hundred dollars, he says, if the sensors are mass-produced.
I had no idea that these sensors could have such an impact. The applications for doctors and behavioral scientists are vast. I also think it is pretty cool that the system uses bat echolocation to work. Sometimes the innovation for great technology comes from nature. Here is a YouTube video detailing the cheap sensor: