U.S. patent number 3,752,929 [Application Number 05/195,392] was granted by the patent office on 1973-08-14 for process and apparatus for determining the degree of nasality of human speech.
Invention is credited to Samuel G. Fletcher.
United States Patent |
3,752,929 |
Fletcher |
August 14, 1973 |
PROCESS AND APPARATUS FOR DETERMINING THE DEGREE OF NASALITY OF
HUMAN SPEECH
Abstract
A process and apparatus is described in which electric signals
representative of the sounds emitted from the nose and mouth are
utilized to determine the degree of nasality of speech. Separate
electric signals are derived from sounds emitted from the nose and
mouth and these are compared one to the other and then the
resultant signal is compared with a signal representative of a
known degree of nasality. A form of apparatus suitable for carrying
out the process is disclosed, including means separately to impress
the nasal and oral signals onto separately functioning
microphones.
Inventors: |
Fletcher; Samuel G.
(Birmingham, AL) |
Family
ID: |
22721243 |
Appl.
No.: |
05/195,392 |
Filed: |
November 3, 1971 |
Current U.S.
Class: |
704/231;
704/E11.001 |
Current CPC
Class: |
G10L
25/00 (20130101) |
Current International
Class: |
G10L
11/00 (20060101); G10l 001/04 () |
Field of
Search: |
;179/1SA,1VS
;128/2R,2.1R ;324/77J |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Claffy; Kathleen H.
Assistant Examiner: Leaheey; Jon Bradford
Claims
What I claim is:
1. In apparatus for analyzing continuous human speech to indicate
the degree of nasality thereof comprising:
a. means to produce separate electric signals directly from the
sounds emitted from the nasal and oral passages of a person being
tested,
b. means to which said signals are separately fed and effective to
emit separate signals representative of the proportionate intensity
of each signal within a predetermined frequency range,
c. means to which the signals from the means set forth in (b) above
are fed and effective to generate another signal which represents
the ratio of said signals which ratio is representative of a known
degree of nasality
d. means to compare said ratio signal to a signal representing a
known degree of nasality, and
e. indicating means responsive to the signal obtained from the
means of (d) above.
2. Apparatus as defined in claim 1 in which the means set forth in
(a) of claim 1 comprises an internally baffled housing disposed
when placed adjacent the face of a person to provide a pair of
sound chambers, one of which chambers communicates with the nasal
passages and the other of which communicates with the oral passage,
and microphones in each of said chambers by which the sounds
emitted from the nose and mouth are caused to produce separate
electric signals.
Description
This invention relates to a process and apparatus for determining
the nasality, or degree of nasality, of human speech.
Heretofore in the diagnosis and treatment of hypernasality, such
condition generally has been diagnosed merely by having the patient
speak to a human listener, the latter of whom then, perceptually,
judges the degree of nasality. Such judgment obviously is directly
related not only to the acuity of hearing of the listener, but also
to background noise, the amount of contact which the listener
previously had had with the subject and with other similar
subjects, as well as other various physical and psychological
factors. Therefore, the concept of determining nasality, and
prescribing treatment for the same, by patient to listener methods
has been found to be inaccurate and ineffective and has lead to a
gross waste of effort both on the part of the patient and the
clinician.
Prior efforts have been made to measure hypernasality by electronic
means. However, sofaras I am aware such prior efforts have
consisted in attempts to utilize the overall sound output from the
patient, namely, the sounds emitted from the nasal and oral
passages, without attempting in any effective way to segregate
these two sounds, analyze the same as they relate to their
respective frequencies and then compare them.
In view of the foregoing an object of my invention is to provide a
process for determining the degree of nasality in human speech
which comprises developing separate electric signals representative
of the sounds emitted from the nasal and oral passages of a patient
being tested, said signals also being representative of the nasal
resonance frequency, and then, utilizing said separate signals, to
relate the same to a signal which is representative of a known
degree of nasality, thus to obtain an indication of the overall
performance of speech, in the sense of nasality.
Another object is to provide a process of the character indicated
which comprises carrying out the operation during continuous speech
of the person being tested and further, as an aid in speech
improvement, continuously to indicate to the person being tested
the degree of peformance during the entire therapy period.
A further object is to provide apparatus which is capable of
carrying out my improved process and which embodies, in particular,
a pair of sound isolated microphones carried by a housing and so
relatively arranged that when the housing is brought into place
about the face of a person the separate sounds from the nasal and
oral cavities are impressed upon the respective microphones, thus
initiating and making possible the production of the electrical
signals with which I start my improved process.
My invention also is characterized by the provision of apparatus
which is reliable in operation and which is responsive to
substantially the entire critical range of resonant frequencies
encountered in human nasality.
Apparatus illustrating the constructional features of my invention
and which may also be used in carrying out my improved process is
shown in the accompanying drawings forming a part of this
application in which:
FIG. 1 is a vertical sectional view, somewhat diagrammatic, and
illustrating an internally baffled housing having separate
microphones therein and which are adapted to produce signals
representative of sounds emitted from the nasal and oral passages
of a person being tested;
FIG. 2 is a front elevational view of the apparatus shown in FIG.
1;
FIG. 3 is a wholly diagrammatic partial wiring diagram of a portion
of my improved apparatus; and,
FIG. 4 is a wholly diagrammatic, schematic wiring diagram of the
remainder of my improved apparatus.
Referring to the drawings it will first be understood that my
improved process starts with and is predicated upon the concept of
producing separate electrical signals which are representative of
the sounds emitted from the nasal and oral passages of a person
being tested. To this end I indicate in FIG. 1 at 10 a housing
which may have a circular lower part 11 and an upper, somewhat
vertically elongated part 12. As illustrated in the drawings the
lower part 11 provides a chamber 13 while the upper part 12
provides a chamber 14. It will be seen, in effect, that the wall
11a of the device 10, when the device is brought into position
relative to a human face as shown, separates the acoustic output of
the nose from the mouth.
Associated with the chamber 13 is a microphone 16 while associated
with the chamber 14 is a microphone 17. Sound pervious pads 18 and
19 of foam rubber or the like may be used, if desired.
It will be seen that with the housing 10 in place adjacent the face
and with the baffle 11a contacting the upper lip of the person,
sounds eminating from the nasal cavities are impressed upon the
microphone 17 whereas sounds from the oral cavity are impressed
upon the microphone 16.
Referring particularly to FIG. 3 signals from the microphones 16
and 17 are lead through circuits 21 and 22 to the respective
frequency analyzers 23 and 24. The analyzer 24 is tuned to nasal
resonancy frequency while the analyzer 23 scans the same frequency
band in the oral signal.
From the frequency analyzers 23 and 24 the signals are sent through
the respective circuits 26 and 27 to the ratio computer, indicated
diagrammatically at 28. In the computer 28 the nasal signal is
divided by the oral signal thus to obtain a quotient signal which
is sent through appropriate circuits 29 to a ratio threshold
detector, the mechanism of which is enclosed within the dotted
outline 31, FIG. 4.
Circuit 32 leads from the microphone 16 to a voice detector, the
mechanism of which is included within the dotted outline 33, FIG.
4.
When sound is impressed on microphone 16 the section of the
apparatus indicated by numeral 33 generates a signal which may be
denominated logic 1 and this is impressed through circuits 34 onto
a time mode function generator indicated within the box 36. In
addition, the signal from the voice detector goes to a sixty cycle
clock 37 and to a trial mode success-fail detector 38.
From what has been so far described it will be seen that the
enumerated mechanism takes the signals from the nasal and oral
passages, converts them into electric signals, analyzes the same
for respective intensity and frequencies and divides the signal
representative of the oral sound into the signal representative of
the nasal sound. This resultant signal is sent through the circuits
29 into the ratio threshold detector 31 and operates the system
either in time or trial mode, depending upon its elected function.
The signal from microphone 16 is also brought to the voice detector
33 to activate the comparative function.
In the ratio threshold detector 31 the signal from circuits 29 is
sent to an amplifying circuit which conditions it to proper
voltages, by way of example, from 0 to 2.4 volts. Also in the
section 31 the signal which has been thus conditioned is compared
with a signal representative of a known degree of nasality, which
by way of example may be 1.8 volts. The comparison signal is lead
through circuits 31a to the 60 cycle clock 37, the time mode
function generator 36 and to the trial mode success-fail detector
38.
Simultaneously with the foregoing the signal through the circuits
32 coming from microphone 16 are fed to the voice detector 33 which
includes an isolation amplifier and sensitivity control therefor, a
rectifier, a filter and a threshold detector. The signal coming
through circuits 32 from microphone 16 is generally on the order of
about 0 to 0.8 volts AC, peak. As before stated, the output through
circuits 34 from section 33 go to the clock 37, the time mode
function generator 36 and trial mode success-fail detector 38.
From what has been so far described it will be seen that the
apparatus provides means to determine during the trial period,
(namely, during the time the person is speaking) whether the degree
of nasality has decreased below the selected level to which the
ratio signal in circuits 29 are being compared.
The trail mode success-fail detector 38 receives the signal from
the voice detector 33 and the ratio threshold detector 31 through
circuits 41 to an eight bit shift register indicated at 42. The
ratio signal is delivered through circuits 43 to a two input NAND
gate 44 and a circuit 46 leads from the gate 44 to the input of a
J-K flipflop 47. Thus, when the signal in circuits 29 indicate a
degree of nasality below the comparison level, the unit 47 sends a
signal through circuits 48 to another two input NAND gate 49. When
a person stops speaking, for instance at the end of a word, the
device 49 gates out a signal which is sent to the success counting
devices indicated in part by the numeral 51 and circuits 52. The
unit 51 may indicate success in the form of a succession of lights,
and so forth. In addition, a circuit 53 may lead to a counter or
counters to totalize the number of successes.
In view of the foregoing it will be seen also that various
ancillary equipment may be associated with my apparatus. By way of
example one may display to the person being tested a succession of
lights, or other indicia, indicating to him his repeated success or
repeated failure, with each attempt to speak a given sentence,
phrase, word or the like.
In actual practice my improved process and apparatus have proven to
be extremely beneficial in the scientific diagnosis and treatment
of hypernasality. By my improved process people of all ages, that
is, children as well as adults have been enabled to reduce their
hypernasality to acceptable levels within a very short time as
compared to months and even years through traditional observation
and treatment. I have thus reduced the science of determining and
treating hypernasality from an individual appraisal basis to that
of an objective, accurately determinable basis. My invention
provides a fixed standard against which a person afflicted with
hypernasality may be advised, continuously, as he speaks, of the
degree of the same and the improvement which he makes while
undergoing observation and testing.
While I have shown my invention in but one form, it will be obvious
to those skilled in the art that it is not so limited but is
susceptible of various other changes and modifications without
departing from the spirit thereof.
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