Abstract:

A computerized electromechanical ultrasound transducer holder is being developed to allow representation of three-dimensional tongue motion. Current three-dimensional ultrasound systems are comparatively slow (10 s/volume) and hence are not useful for the study of dynamic three-dimensional speech. The proposed mechanism will (automatically) both scan along and rotate about an axis, sensing transducer position and providing feedback. This motion will be motorized and controlled by a computer according to custom-developed software and parameters. One can program the computer to perform a synchronized series of approximately five sagittal or coronal slices. These slices can later be assembled and interpolated to form a three-dimensional surface model. Mechanically, this system is advantageous because it rotates the transducer about a virtual center, which is located along the axis of the center of the arc of the piezoelectric crystals within the transducer, and does not necessitate additional mechanical structures near the subject. The electrical and computer control system will allow automated imaging of a series of coronal or sagittal slices synchronized in time and located precisely in space. This system will be added to and used in conjunction with the HATS system described in Stone and Davis [J. Acoust. Soc. Am. 98, 3107--3112 (1995)]. [Work supported by Northrup Grumman and NIH.] XXSU SC