We have implemented a near-ultrasonic communication protocol in the 18.5-20 kHz band, which is inaudible to most humans, using commodity smartphone speakers and microphones to transmit and receive ...

The authors propose a radar made with the ultrasonic sensor type HC - SR04, developed for Arduino. The novelty added by this paper is the development of specific libraries aiming to interface the ...

Modern RC cars can be pretty darn fast. That’s fun and all, but it also makes it easy to crash them into things. This problem ...