Keith Baxter from the The Milwaukee Servoelectric Guitar Project sent in the cool progress he is making on the Single String Servo Guitar project. You probably remember Keith from the original Servo Guitar that we featured last year. There is something haunting and pleasant sounding with this new single string guitar, I wonder if Keith could rig something up so that it could pick the string and control the servo so that it could play a tune all by itself? If you are interested in making your own there are full schematics available.
“This design uses two Arduios, a first Arduino that receives MIDI data and interprets it to a note within the one octave obtainable by the string. The second Arduio converts the note number to a tension of the string, allows tuning of the string (adjusting a table that converts new to string tension) and handles the control algorithm for the servo motors. For a four string design, three Arduinos would be used, one for MIDI decoding and two each handling two strings. The servo amplifier is the same as used in previous designs. This design also provides autotuning to slowly correct any string drift over time. The autotuning uses a variation of autocorrelation called average magnitude difference to detect string tuning opportunistically between notes.”