could he get the same effects with off-the-shelf components? [Nubmian] created a rig using a pair of typical ultrasonic distance sensors. He detached the two transducers from the front of the PCB.

sensor coupled with a Zigbee interface. Inside the ultrasonic welded case is a small PCB and a Fresnel lens on the inside of the top cover, and a small PCB for the electronics. We applaud the use ...