The Pidato experiment demonstrates a rather straightforward method to handle vibrato on a digital piano. It ‘solves’ the age-old problem on what to do with the enigmatic “vibrato” instructions on some piano solo scores of Franz Liszt.
The way it works is by translating movement (accelerometer data) to MIDI messages. Pidato consists of a hardware and software part. The hardware consists of an Arduino, MIDI-ports and a three axis accelerometer. The software should know when a vibrato like movement is made and how to translate such movement to MIDI messages. The software therefore contains a periodicity estimator and frequency detector to detect how periodic a movement is and how fast the movement is repeated. This was done with the YIN algorithm (more commonly used in audio signal analysis).
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