Development of an Improved Tactual Vocoder

Period of Performance: 09/01/1994 - 05/31/1996


Phase 2 SBIR

Recipient Firm

Intelligent Hearing Systems
Miami, FL 33143
Principal Investigator


DESCRIPTION: (Adapted from the Applicant's Abstract.) Intelligent Hearing Systems proposes development of awearable tactual vocoder, an artificial hearing system worn on the skin, to assist the deaf in learning to communicate verbally. Previous commerciallyavailable tactileaids have had three important drawbacks: such systems 1) have been based upon inflexible analog circuitry, and consequently have not been programmable to accommodate special needs of individual users or programs of rehabilitation, 2) have been ineffective as transmitters of fundamental frequency (pitch), one of the key factors in the success of surgically implanted artificial hearing systems, and 3)have not been capable of transmitting rapid spectral cues (format transitions), one of the most important characteristics of the speech code. The proposed IntelliVoc (Intelligent Vocoder) device would address the failures of previously available systems by 1) providing a miniaturized system that can be programmed by a speech and hearing clinician to adapt the systems's characteristics (channel allocation, dynamic range, frequency coding etc.) to the individual needs of users or programs of rehabilitation, 2) utilizing a new wideband vibrator to transmit pitch intonation contours directly as frequency of vibration to the skin, and 3) employing a realtime Linear Predictive Coding (LPC) signal processing approach to deliver formants and formant transitions to the skin.