Researchers from Carnegie Mellon University have developed a system called acoustic barcodes that registers the sound of a finger scraping across notches etched, embossed or cut into a surface, and converts it into a unique binary ID
An acoustic barcode patterned into an acrylic tag
Teaching aids enhanced with acoustic barcodes
Unique IDs carved on various parts of the ship can be swiped to access information on the different functions
The system is capable of using the internal microphone of mobile devices to register the acoustic barcodes
Acoustic barcodes can be incorporated into a variety of materials, including polystyrene (vacuum-formed), paper, transparency, wood, glass, acrylic, granite, and a 3D-printed object
The team also succesfully etched an acoustic barcode onto type 1 polyester transparencies
An acoustic barcode (B) is placed on a table (I), and a microphone (C) is attached. A fingernail (A) running over the barcode produces a series of mechanical vibrations (D), which propagate through the table and are captured by the microphone. The first sound is the initial impact of the finger (E). As the nail passes over the notches in the acoustic barcode, a series of sharp bursts of sound are produced (F). Finally, the finger lifts off or falls of the end of the barcode (G). The resulting waveform is processed, resulting in a decoded binary sequence (H).