Towards real-time two-dimensional wave propagation for articulatory speech synthesis

The precise simulation of voice production is a challenging task, especially when real-time performances are sought. To fulfill real-time constraints, most articulatory vocal synthesizers have to rely on highly simplified acoustic and anatomical models, based on 1D wave propagation and on the usage of vocal tract area functions. In this work, we present a 2D propagation model, designed to simulate the air flow traveling through the midsagittal contour of the vocal tract. Building on the work by Allen et al. [Andrew Allen and Nikunj Raghuvanshi, “Aerophones in flatland: Interactive wave simulation of wind instruments,” ACM Trans. Graph. 34, Article 134 (2015)], we leverage OpenGL and GPU parallelism for a real-time precise 2D airwave simulation. The domain is divided into cells according to a Finite-Difference Time-Domain scheme and coupled with a self-oscillating two-mass vocal fold model. To investigate the system’s ability to simulate the physiology of the vocal tract and its aerodynamics, two studies a...