A combination of movement sensors and ultrasound emitters might lead to versatile motion capture systems for controlling computers
Several sensors measuring about 2.5 centimetres 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.
