[posted] SPO • electronic string instrument 2.0 • playing with hand gestures

The 1.0 version of the instrument was presented to the public several times. For the first time on July 14, 2019 at the “night of sience” at the University of Frankfurt, and in 2019 at the SKOP festival “Computer-Music V” in Frankfurt. Due to the corona pandemic, the other concerts with the instrument could only take place via the Internet, on March 29, 2020 and October 21, 2020. A composition by Phill Niblock, New York was realized with the instrument and came in December 2020 in New York, at Roulette, premiered. The development of the instrument began 3 1/2 years ago and at the beginning it was not foreseeable that it would develop in this way.
Some developments have been made since version 1.0. They include extensions on the software and hardware side.
Tunings Systems
Pure tuning, Pythagorean tuning, 6th-root-of-2, 53th-root-of-2 and 106th-root-of-2. These tunings found their previous applications in different programming / compositions. The tuning systems are combined as a unit to display small and smallest intervals. Individual tuning systems are visually indicated by different colors of the LEDs, see picture. When certain positions are reached, the corresponding LEDs flash.
Extension of the instrument by a light case with 189 LEDs. Here the different tunings are marked by different colors, see picture.
Gesture Control Camera
Augmented Reality, the instrument can be classified under this heading. The instrument becomes augmented reality essentially through the Kinect V2 camera, because it makes the instrument playable for "all people" via gesture control and light signals.
Left hand controls the left slider with the pick, right hand controls the right slider with the string divider. Close left hand, strike the pick. Close right hand, string divider up. Pointer finger and middle finger of the right and left hand control the loud-quiet motor. The illuminated LEDs show the way across the instrument and thus into the possible tonal range.
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Anyone can play the instrument. No knowledge is required. The only request: always play within the range of the lighted LED's and listen to the notes.
Computer - Microcontroller
Notebook: i7, 32 GB RAM, Windows 10, runs the Kinect camera program and sends the data to the interface.
Microcontroller: 1 teensy 3.6 controls 5 motors; different arrays talk to the LEDs, which are coupled with arrays of motor positions; evaluates the camera data and sends the data to the motors. A small controller interfaces the camera data to the teensy via TX and RX. The camera-Teensy interface was programmed by Thomas Perizonius, who was also involved in the development of the pickups. The development time so far is 3 1/2 years.
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Looks like the forum may have lost track of a couple attached files. If they're not the 2 thumbnails, can you repost those file?
Hallo Paul Stoffregen,
thanks you for this info. I had made a mistake during the upload and could not correct it. Here now a new image for the overview to the SPO 2.0SPO_played_with_handgestures.jpg
Two programs with SPO 2.0 are available: colored LED's guide you through the tonal space where plectrum actions can be activated by you. "Find The Pure Consonants" and „Play Around The LED’s“ so the two programmings. The colored programming of the LEDs are a great support for your playing.

So that the game can be useful by everyone, I have programmed certain LED light sequences. Also, a player should be stimulated to want to play for a longer period of time. With an undirected game the desire is lost quickly, so it was indispensable for me to provide some variety. The programming for this is very extensive, but can be varied relatively quickly. However, the basic idea of the compositions should be able to appear with each new variation.

In September 2022, the public will be able to play the instrument at an event in Prague and Frankfurt.
The instrument was now presented twice within one concert: In December 2021 with a composition by Phill Niblock in New York, realized with the 1.0 version, see images and the link to the mp3-file, furthermore with a composition by me in October in Helsinki with the 2.0 version. Hand gesture controlled, augmented reality.

For 6 hours of film and music by Phill Niblock at "Roulette Intermdedium" in December 2021. The composition "Exploratory, Rhine version "Looking for Daniel", #9(number nine)" by Phill Niblock was realized with the SPO and premiered within this event. Here is the composition with a link to my website and a picture showing a major extension of the instrument, the Ebow.

Play with SPO 2.0 in Helsinki via stream went well. Had very good feedback from Helsinki and Germany. Am very pleased with how it went. In the play I was able to realize a lot of the composition, which was good.
Here is a picture of the evening from Helsinki and Frankfurt and a link from an rehearsel:

Now, almost 4 years later and very very many hours the Teensy 3.6 has done its job: no failure with the microcontroller. I am very happy about that. Thanks for that Paul Stoffregen.