EchoLocation as Biometric Activity Data

A reminder that any kind of data that results from interaction with its environment can be probed for pattern.   And thus provide learnable details.

This AI Uses Echo Location to Identify What You are Doing in Wired by Sophia Chen

GUO XINHUA WANTS to teach computers to echolocate. He and his colleagues have built a device, about the size of a thin laptop, that emits sound at frequencies 10 times higher than the shrillest note a piccolo can sustain. The pitches it produces are inaudible to the human ear. When Guo’s team aims the device at a person and fires an ultrasonic pitch, the gadget listens for the echo using its hundreds of embedded microphones. Then, employing artificial intelligence techniques, his team tries to decipher what the person is doing from the reflected sound alone.

The technology is still in its infancy, but they’ve achieved some promising initial results. Based at the Wuhan University of Technology, in China, Guo’s team has tested its microphone array on four different college students and found that they can identify whether the person is sitting, standing, walking, or falling, with complete accuracy, they report in a paper published today in Applied Physics Letters. While they still need to test that the technique works on more people, and that it can identify a broader range of behaviors, this demonstration hints at a new technology for surveilling human behavior. ... " 

Echolocation Robot

Besides navigation is also doing classification of objects it encounters

Bat-Inspired Robot Uses Echolocation to Navigate 

By Kenny Walter, Tel Aviv University

Researchers at Tel Aviv University in Israel have developed Robat, a fully autonomous bat-like robot that uses echolocation to move through new environments. Robat includes a biologically plausible signal processing approach to extract information about an object's position and identity, a feature that makes the system unique among other attempts to apply sonar to robotics. The system contains an ultrasonic speaker that mimics the mouth of a real bat and produces frequency modulated chirps similar to those of bats. In addition, Robat is equipped with two ultrasonic microphones that mimic ears. The robot uses an artificial neural network to delineate the borders of objects it encounters and classify them. During testing, Robat was able to move autonomously through novel outdoor environments and map them using only sound. The researchers also found that the robot was able to classify objects with a 68% balanced accuracy, and to determine obstacles with a 70% accuracy. ... "