ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06

5aSC2. Recovery of task-dynamic parameters with a mismatched articulatory model.

Richard S. McGowan

Mindy Lee

Haskins Labs., 270 Crown St., New Haven, CT 06511

A method for recovering task-dynamic parameters from speech acoustics has been proposed [see McGowan, Speech Commun. 14, 19--48 (1994)]. In the series of tests to be described here, there were mismatches imposed between the task dynamics that produced the speech data and the task dynamics used in the analysis-by-synthesis procedure for recovery. One of the mismatches was in the articulator weights used in specifying how much of each articulator to use in attaining construction goals. Another mismatch was in the allowed relation between activation interval and the natural frequency of the constriction dynamics (natural frequency constraint). Bilabial and velar places of articulation (constriction) were tested, and the first three formant trajectories were used as data. When there was articulator weight mismatching, it was found that articulators would compensate so that the recovered constriction trajectories were similar to those of the data producing trajectories. It appeared to be more difficult to overcome mismatches in the natural frequency constraint. Also, the nonuniqueness of the recovered task dynamics is exhibited when there is not sufficient acoustic data. [This work was supported by NINDCD Grant 01247 to Haskins Laboratories.]