Articulatory control of a vocal tract model based on fractional delay waveguide filters

A novel technique to implement and control an acoustic tube model of the human vocal tract is introduced. This model is an extension to the traditional Kelly-Lochbaum model, since not only the diameter of individual uniform tube sections but also their length, i.e., the positions of scattering junctions, can be continuously varied. The vocal tract model is implemented by means of FIR-type interpolation and deinterpolation that are used to locate the junctions. The authors show that in this kind of model the articulators can be presented in a natural manner enabling easy control of the model from articulatory data