Analog ear

Abstract: It is now a well-accepted fact that the transmission response of the human ear from the pressure incident at the pinna to displacement of the basilar membrane provides a means of resolving an incident acoustic signal into its spectrum energy distribution. However, due to the inherent nature of this transmission response, the resolution of the spectrum energy distribution that is produced is very poor, and is not at all in concert with the well-known capacity of human hearing for the perception of frequency. This paper reports on a system that is currently being experimentally pursued for enhancement of the resolution of the spectral energy transfer response of the basilar membrane to incident acoustical signals. The system consists of a 40-section electrical network analog of the basilar membrane displacement. The signal energy intercepted by each section is detected and then processed by a high-order differencing network. Differencing networks up to the sixth order are being investigated. Experimental evaluation shows that a second-order differencing network significantly enhances the peak structure of the pattern generated by the basilar membrane analog, and defines with reasonable resolution the formants of the input utterances. Higher order networks appear unnecessary and even detrimental.

Abstract: We subscribe to a certain philosophy for hearing. Our concept amounts to a “pattern” theory. In order to test this theory and to provide a useful real-time tool (independent of the pattern theory), we are implementing our concepts in the form of an analog ear. Insofar as is reasonable, parts of the analog bear a one-to-one relationship with parts of the ear. In this way it is hoped that the device will provide clues for the otologist as well as for the psychologist concerned with problems in recognition.

Abstract: : An elctrical analog of the human ear is described, which includes the external and middle ear, the cochlea, and part of the the neutral structure of the cochlea and the higher auditory centers of the central nervous system. The analog is devel oped on the basis of a one-to-one relation be tween physiological and ecal parameters. The electrical analog cochlea is realized as a 36-section, lumped-parameter, nonuniform trans mission line. The neural structure of the cochlea and auditory portions of the central nervous system are modeled functionally by means of 36 detecting and filtering amplifiers, termed loudness converters. The spatial array of the 36 loudness converter outputs is a neutral equivalent pattern of basilar membrane motion. A pattern theory of loudness detection and sound recognition is discussed. On the basis of this theory, the analog ear exhibits a threshold of hearing curve which is approximately the same as that for a human. The important mechanical variable is found to be the velocity of the basilar membrane. The neural volley effect is included. Studies indicate that sound recogni tion with the analog is similar to that for a human. (Author)

Abstract: The invention provides a slope-intercept form bionic bat ear horn model function device and an experiment method. The slope-intercept form bionic bat ear horn model function device comprises a controlpart, a slope-intercept analog auricle, an auricle cone angle adjusting part, an auricle tangent plane angle adjusting part and an analog ear canal; the auricle cone angle adjusting part is used forreceiving an auricle cone angle adjusting command issued by the control part, and adjustment of the slope-intercept analog auricle cone angle is achieved; the auricle tangent plane angle adjusting part is used for receiving an auricle tangent plane angle adjusting command issued by the control part to achieve adjustment of the slope-intercept analog auricle tangent plane angle; one end of the analog ear canal is connected with the slope-intercept analog auricle, and the other end of the analog ear canal is connected with an ear canal position adjusting part; the ear canal position adjusting part is used for receiving an ear canal position adjusting command issued by the control part to achieve adjustment of the ear canal position.