Final Project – UltraSonic

Nkinde Ambalo, Horace Hou


For our project, Ultrasonic, we created a device that tries to quantify a sense that we, humans, can’t sense. Using a microphone and a PureData patch we created a device that can sense ultrasonic sound waves in the range of 18kHz to 20kHz. Using this information we are able to tone the frequency of the sound waves to what humans are able to perceive. Also the strength of the signal changes the volume of the sound outputted. Using this information we also wanted to be able to map the what the variety and sources of ultrasonic waves that exist in a persons environment.

Technical Aspects

Our project consisted of a raspberry pi running pure data. The patch running on pure data watched for the plugged in microphone input level to go higher than the usual for background noise. When it did it played sound through the connected output device, sound which was pitched down 6 octaves from the input sound. This allowed anyone to hear sounds that could have been above their threshold of hearing, as the high frequency tone would be below 10,000 hz. The raspberry pi had to have an external usb sound card connected to it so that it could accept both a recording device as well as output to a speaker device. Other than power, no other cables were connected to the Raspberry Pi. In the plan for this device there was also the plans to add a gps device connected to the pins of the raspberry pi, or a bluetooth adapter connected to a smartphone pinging the location of the phone every time high frequency sound was detected.