http://artscool.cfa.cmu.edu/~winkler/Waves/index.html

Project Description
In our proposed project, buoys swaying on the water’s surface will create unique sound compositions generated by the energy of waves in a wading pool. An accelerometer in each buoy measures the magnitude of waves through x- and y-axis position changes caused by the rocking back and forth of the buoy on the water’s surface. The accelerometer’s readings are then converted into sound waves by a microcontroller connected to a SPEAKjet sound synthesizer IC. Finally, the SPEAKjet’s output is amplified and sent to a speaker integrated into the buoy. Each buoy plays a electronically generated minimalistic tone that reflects the participant’s movements in the wading pool.
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