The VibroChord

The Vibrochord (see Figure 1) and a gesture interface for the Emoti-chair. The Vibrochord is a new system designed to allow artists and individuals to play vibrational music through the Emoti-chair. The gesture interface uses a Kinect system to allow users to move their hands, arms and bodies to also play/conduct vibration music through the Emoti-chair.

The Vibrochord is a new keyboard-like device, that when coupled with the vibrotactile display The Emoti-Chair, enables a new art form, vibrotactile music. Vibrotactile music is much like audio music, in which patterns of vibrations are presented to a recipient over time, however vibrotactile music presents vibration to the skin as vibrotactile stimulation rather than to the ear as sound.

Studies investigating The Emoti-Chair show that some of the emotional content of audio, when delivered as vibrotactile stimulation through The Emoti-Chair can be conveyed to users. Additionally, other elements of music such as timbre have also been shown  to be conveyed successfully through vibrotactile stimulation.

Although the human hearing and vibrotactile perceptual system are strikingly similar, the vibrotactile system suffers from several crucial limitations. First and foremost the vibrotactile perceptual system is capable of perceiving a much smaller range of frequencies:

  • (20 Hz – 1000 Hz) when compared to that of the human hearing system
  • (20 Hz – 20 000 HZ). Additionally, the difference limens for frequency discrimination in the vibrotactile system are much larger than that of the hearing system.

The aforementioned limitations of the vibrotactile perceptual system limit the number of musical elements or “notes” available to a vibrotactile musician or composer. However, The Emoti-Chair, due to its eight independent channels of vibrotactile stimulation can encode signals using not only frequency and amplitude but also space, offering an additional dimension of encoding and effectively increasing the number of musical elements available for use by a factor of eight. The Vibrochord in conjunction with The Emoti-Chair, takes full advantage of this additional dimension of encoding.