JP2005030851A - Sound source position specifying system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately specify the position of each sound source by collecting sound from a plurality of different positions. <P>SOLUTION: Breath sound data are simultaneously collected from a plurality of different positions of a human body by collection microphones 2a, 2b, 2c, 2d and 2e, while emitting sound waves at different time points by sound wave generating means 14a, 14b, 14c, 14d and 14e provided on the collection microphones 2a, 2b, 2c, 2d and 2e, respectively. The relative positions of the collection microphones 2a, 2b, 2c, 2d and 2e are calculated based on the sound waves in the breath sound data collected by the collection microphones 2a, 2b, 2c, 2d and 2e. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sound source position specifying system that collects sound and specifies the position of a sound source.
[0002]
[Prior art]
For a long time, auscultation of respiratory sounds has been used as an important diagnostic and diagnostic means by doctors. In recent years, with the advancement of medical technology, advanced diagnostic equipment and data processing technology have been developed, and auscultation of respiratory sounds remains in the conventional form. Medical forms are also diversifying, and there is a demand for objective diagnosis and storage of diagnostic data for explanation to patients, medical examinations at home and home nursing, and prevention and confirmation of medical errors.
[0003]
However, since the raw data is lost at the moment the doctor listens, it is difficult to give detailed explanations to the patient based on the data. On the other hand, it is difficult for the patient to grasp his / her medical condition objectively. Can not. In addition, regarding the auscultation information obtained by the nurse's visiting care, the doctor's judgment is transmitted to the doctor, but the doctor cannot directly listen to the raw information. For auscultation that requires skill, an auscultation device is required that enables advanced medical examinations for non-doctors.
[0004]
In the diagnosis of breathing sound, there is a method in which sounds are collected from a plurality of positions, the characteristics of each sound are analyzed, and at the same time, the diagnosis is made paying attention to the difference in sound depending on the position. For example, in the lower part of the lungs, it is normal for inspiration to be heard but for exhalation to be small or almost inaudible. On the other hand, if water accumulates in the lungs, sound transmission is improved and exhalation may be heard in the lower lungs. From this, when exhalation can be heard in the lower lung, it is diagnosed that there is a high possibility that water has accumulated. Thus, in order to diagnose with high accuracy, it is preferable to collect sounds from a plurality of positions and compare them. For this reason, a technique is disclosed in which breathing sounds are simultaneously collected by a plurality of microphones and the breathing sound collection positions are displayed three-dimensionally (see, for example, Patent Document 1).
[0005]
In addition, a sound source search system that specifies and displays the position of a noise source in a factory or the like indoors and outdoors has been disclosed (see, for example, Patent Documents 2 and 3).
[0006]
[Patent Document 1]
US Pat. No. 6,139,505 [Patent Document 2]
JP 2002-181913 [Patent Document 3]
Japanese Patent Laid-Open No. 2003-111183
[Problems to be solved by the invention]
However, in the above-described prior art, the relative position between the microphones that collect the sound is determined in advance both in the living body and indoors, and when the sound is collected, the microphone must be fixed at a predetermined position. did not become. For example, when collecting breathing sounds, it is necessary to attach microphones to different sizes for patients with different body types, such as adults and children, men and women, and lean and fat people. Become. However, since the optimum sampling position is different for each, it may not be possible to accurately collect respiratory sounds.
[0008]
The present invention has been made in view of the above-described problems in the prior art, and provides a sound source position specifying system capable of collecting sound from a plurality of different positions and accurately specifying the position of each sound source. Is an issue.
[0009]
[Means for Solving the Problems]
The invention according to claim 1 for solving the above-described problem is a sound source position specifying system for specifying the position of a sound source corresponding to each of a plurality of sound sampling means, and a sound wave provided in the vicinity of each sound sampling means. A sound source position specifying system comprising: a sound wave generating unit that emits sound; and a calculation unit that calculates a relative position of each sound sampling unit based on the sound wave generated by each sound wave generating unit.
[0010]
According to the first aspect of the present invention, since the relative position of each sound sampling means is calculated based on the sound wave generated by each sound wave generating means, the position of each sound source corresponding to each sound sampling means is accurately determined. Can be identified.
[0011]
A second aspect of the present invention is the sound source position specifying system according to the first aspect, wherein the plurality of sound sampling means collect a biological sound from a human body.
[0012]
According to the second aspect of the present invention, since the relative position of each sound sampling means on the human body is calculated, the body sound can be collected at the optimum collection position for each patient.
[0013]
According to a third aspect of the present invention, in the sound source localization system according to the second aspect, each of the sound wave generating means emits a sound wave during a period in which a biological sound is collected by the plurality of sound collecting means. This is a sound source location system.
[0014]
According to the third aspect of the present invention, since each sound wave generating means emits a sound wave during the period in which the body sound is collected, the relative position of each sound collecting means at the time of the body sound collection can be calculated. it can.
[0015]
According to a fourth aspect of the present invention, in the sound source position specifying system according to any one of the first to third aspects, sound waves generated by the sound wave generating means have different frequencies from each other. It is a specific system.
[0016]
According to the fourth aspect of the present invention, since the sound waves generated by the sound wave generating means have different frequencies, the positions of the sound collecting means can be easily distinguished.
[0017]
According to a fifth aspect of the present invention, in the sound source position specifying system according to any one of the first to fourth aspects, the sound wave generating means emits sound waves at different timings. System.
[0018]
According to the fifth aspect of the present invention, since each sound wave generating unit emits a sound wave at a different timing, the position of each sound collecting unit can be easily distinguished.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a schematic configuration of a sound source position specifying system 1 in the present embodiment. As shown in FIG. 1, the sound source localization system 1 includes a breathing sound collection microphone (hereinafter referred to as a collection microphone) 2a, 2b, 2c, 2d, 2e, a signal processing means 3, an input means 4, a reproduction means 5, It comprises a display means 6, a printing means 7, a database 8, and the like.
[0020]
Respiratory sound data simultaneously collected from the human body by the sampling microphones 2a, 2b, 2c, 2d, and 2e is subjected to signal processing by the signal processing means 3 while referring to the data stored in the database 8 in accordance with instructions from the input means 4. . The processing result is output by the reproducing means 5, the display means 6 or the printing means 7.
[0021]
FIG. 2 shows a functional configuration of the sound source location specifying system 1.
The sampling microphones 2a, 2b, 2c, 2d, and 2e collect respiratory sounds from the human body and output electrical signals (respiratory sound data). Various microphones can be used as the sampling microphones 2a, 2b, 2c, 2d, and 2e. For example, an electric condenser microphone or a piezoelectric element is used.
[0022]
Further, as shown in FIG. 3, a sound wave generating means 14a for emitting a sound wave is provided in the vicinity of the sampling microphone 2a. Similarly, the sampling microphones 2b, 2c, 2d, and 2e are provided with sound wave generation means 14b, 14c, 14d, and 14e, respectively. The sound waves generated by the sound wave generating means 14a, 14b, 14c, 14d, and 14e are sound waves having different frequencies. These sound waves may be sound waves in the audible region or ultrasonic waves. However, if ultrasonic waves are used, a separate microphone from the collection microphones 2a, 2b, 2c, 2d, and 2e is required. In consideration of the combined use with the sampling microphones 2a, 2b, 2c, 2d, and 2e, it is desirable that the sound wave be in the audible region. Moreover, since the sound wave of a high frequency area | region among sound waves of an audible area | region is large attenuation | damping, it is preferable that it is 20Hz-3000Hz, and it is more preferable that it is 50Hz-2000Hz.
[0023]
As shown in FIG. 2, the signal processing means 3 includes a CPU (Central Processing Unit) 9, an I / O 10, a ROM (Read Only Memory) 11, a RAM (Random Access Memory) 12, and a storage means 13. As the signal processing means 3, a PC (Personal Computer: personal computer) or a PDA (Personal Digital Assistant: portable terminal) is used.
[0024]
In accordance with various instructions input from the input means 4, the CPU 9 develops a program designated from various programs stored in the ROM 11 in the work area of the RAM 12 and executes various processes in cooperation with the program. The processing result is stored in a predetermined area of the RAM 12.
[0025]
The I / O 10 receives the respiratory sound data output from the sampling microphones 2a, 2b, 2c, 2d, and 2e and outputs it to the CPU 9.
[0026]
The ROM 11 is composed of a nonvolatile semiconductor memory. The ROM 11 stores various programs, data, and the like of the sound source position specifying system 1 executed by the CPU 9.
[0027]
The RAM 12 is composed of a rewritable semiconductor element. The RAM 12 is a storage medium in which data is temporarily stored. The RAM 12 stores a program area for developing a program to be executed by the CPU 9, data input from the input unit 4, various processing results by the CPU 9, and the like. Data areas, etc. are formed.
[0028]
The storage unit 13 includes an HDD (Hard Disk Drive), and stores respiratory sound data collected by the collection microphones 2a, 2b, 2c, 2d, and 2e, processed data, and the like.
[0029]
The input means 4 is a keyboard provided with numbers, alphabet input keys, and various keys. When these keys are pressed, a pressing signal is output to the CPU 9.
[0030]
The reproduction means 5 includes a speaker or headphones, and acoustically reproduces the respiratory sound data collected by the collection microphones 2a, 2b, 2c, 2d, and 2e.
[0031]
The display means 6 comprises a CRT (Cathode Ray Tube), a liquid crystal display, a plasma display, etc., and the respiratory sound data visualized by the signal processing means 3, and the respiratory sound extracted by the signal processing means 3 The feature, the type of disease candidate, or the probability corresponding to the disease candidate is displayed. Here, the visualization process means a process for making a visually recognizable state such as a graph or a table.
[0032]
The print means 7 prints on the recording paper the respiratory sound data visualized by the signal processing means 3, and the characteristics of the respiratory sounds extracted by the signal processing means 3, the type of disease candidate, or the probability corresponding to the disease candidate. .
[0033]
The database 8 stores disease case data that can be diagnosed from respiratory sounds, disease candidate types, and the like.
[0034]
Next, the operation of the sound source position specifying system 1 in the present embodiment will be described.
As a premise of the operation description, a program for realizing the processing described in the flowchart is stored in the ROM 11 in the form of a program code that can be read by the CPU 9 of the sound source location specifying system 1, and the CPU 9 The operation according to the program code is executed sequentially.
[0035]
FIG. 4 is a flowchart showing the respiratory sound signal processing executed by the sound source location system 1.
[0036]
First, respiratory sound data is simultaneously collected from a plurality of different positions on the human body by the sampling microphones 2a, 2b, 2c, 2d, and 2e. During the period when respiratory sound data is collected, sound waves are generated at different timings by the sound wave generating means 14a, 14b, 14c, 14d, 14e, and these sound waves are also collected by the sampling microphones 2a, 2b, 2c, 2d, 2e. (Step S1). The collected respiratory sound data is stored in the storage means 13.
[0037]
Next, relative to each sampling microphone 2a, 2b, 2c, 2d, 2e based on the sound wave in the respiratory sound data sampled by each sampling microphone 2a, 2b, 2c, 2d, 2e by the signal processing means 3. A correct position is calculated (step S2). For example, sound waves generated by the sound wave generation means 14b, 14c, 14d, 14e are detected from the respiratory sound data collected by the collection microphone 2a, and the sound wave generation means 14b, 14c, 14d, 14e emit sound waves. The distance between the sampling microphones 2a-2b, 2a-2c, 2a-2d, and 2a-2e is calculated based on the time until the sampling microphone 2a senses the sound wave. Similarly, the distance between different collection microphones is calculated. The relative positions of the sampling microphones 2a, 2b, 2c, 2d, and 2e are calculated based on the distance between the sampling microphones 2a, 2b, 2c, 2d, and 2e.
[0038]
Here, a method of calculating the relative positions of the four points A, B, C, and D where the sampling microphones 2a, 2b, 2c, and 2d are located will be described. The calculation of these relative positions is the same as the calculation of the relative positions of the vertices by placing a triangular pyramid on the XYZ coordinates. Since it is a relative position, the placement of the triangular pyramid on the coordinates is arbitrary. As shown in FIG. 5, the position of the sampling microphone 2a is the origin A (0, 0, 0), and the position of the sampling microphone 2b is X The point B (Xb, 0, 0) on the axis, the position of the sampling microphone 2c is the point C (Xc, Yc, 0) on the XY plane, and the position of the sampling microphone 2d is the point D (Xd, Yd, Zd). . For these six variables Xb, Xc, Yc, Xd, Yd, and Zd, six distances between the sampling microphones 2a, 2b, 2c, and 2d are obtained, so that the relative position is obtained from the simultaneous equations. Can do.
[0039]
Here, the method of calculating the relative position of the sampling microphones 2a, 2b, 2c, and 2d has been described, but the position of the sampling microphone 2e can be calculated in the same manner. The number of collection microphones is not limited to five, and may be any number of two or more. Similarly, the relative position of each collection microphone can be calculated.
[0040]
Actually, by specifying the positions of two sampling microphones among the sampling microphones 2a, 2b, 2c, 2d, and 2e, the absolute position in the human body can be obtained. For example, on the back of the human body, the collecting microphones 2a, 2d are placed symmetrically with respect to the spine, at a position 10 cm from the spine, and at the height of the sixth spine from the top, thereby obtaining the respective collecting microphones 2a, 2b, 2c. , 2d, 2e in the human body are obtained. Thus, the position of each sound source corresponding to each sampling microphone 2a, 2b, 2c, 2d, 2e can be specified.
[0041]
However, it is known that the way in which sound is transmitted in the living body is different from that in the air, and an error occurs when calculating at a simple sound speed. For example, J Appl Physiol 93: 667-674, 2002 and J Appl Physiol 94: 604-611, 2003 propose a composite model for sound transmission speed, and this can also be used. It is considered that the microphone having the largest intensity ratio is close to the sound source of the sound element among a plurality of sound elements as a very rough position specification.
[0042]
Next, the collected breathing sound data is filtered to remove noise from the breathing sound data (step S3). At this time, it is preferable that the sound waves generated by the sound wave generating means 14a, 14b, 14c, 14d, and 14e are also removed. The breathing sound data from which noise has been removed is acoustically reproduced by a speaker or headphones (reproducing means 5) according to an instruction from the input means 4 (step S4). At this time, breathing sound data collected from different positions using a plurality of speakers or left and right speakers of headphones may be reproduced simultaneously. Moreover, it is good also as comparing with the past respiratory sound data of the same patient, and the respiratory sound data peculiar to each disease.
[0043]
Next, FFT processing is performed on the respiratory sound data from which noise has been removed (step S5). The FFT processing result is visualized in accordance with an instruction from the input unit 4, and is displayed in a graph by the display unit 6 in association with the sampling position (step S6). A sound spectrogram, a numerical value serving as a reference for diagnosis, or the like may be displayed.
[0044]
Next, the difference at each sampling position is referred to for the amplitude or tone color of the breathing sound, the breathing sound data collected simultaneously at a plurality of different sampling positions is analyzed, and the feature of the breathing sound is extracted (step) S7). In analyzing respiratory sound data, an analysis technique based on wavelet analysis, an analysis technique for speech recognition, or the like can be used. The respiratory sound data and the characteristics of the respiratory sound are compared with the case data of the disease stored in the database 8 (step S8), the disease candidate is selected, and the probability corresponding to the disease candidate is calculated (step S8). S9).
[0045]
Then, according to the instruction from the input means 4, the characteristics of the breathing sound, the type of disease candidate, and the probability corresponding to the disease candidate are displayed by the display means 6 (step S10). For example, the display means 6 may say, “Intermittent sound in the upper left lung, intensity 5. Large inspiration sound in the lower left lung. Intermittent pattern candidates are 70% hypersensitive alveolitis, 50% pneumonia.” Is displayed.
Thus, the breathing sound signal processing ends.
[0046]
According to the sound source location specifying system 1 in the present embodiment, relative to each of the sampling microphones 2a, 2b, 2c, 2d, 2e based on the sound wave emitted by each sound wave generating means 14a, 14b, 14c, 14d, 14e. Since the position is calculated, the position of each sound source corresponding to each sampling microphone 2a, 2b, 2c, 2d, 2e can be specified with high accuracy. Therefore, a breathing sound can be collected at an optimum collection position for each patient.
[0047]
Further, since the sound wave generating means 14a, 14b, 14c, 14d, and 14e emit sound waves during the period in which the breathing sound data is collected, the collecting microphones 2a, 2b, 2c, 2d, and 2e at the time of collecting the breathing sound data are collected. Relative position can be calculated. Since the sampling microphones 2a, 2b, 2c, 2d, and 2e are attached to the human body, the positions thereof vary depending on the respiratory motion. Therefore, it is preferable to calculate the relative positions of the breathing sound data while collecting them.
[0048]
Further, since the sound waves generated by the sound wave generating means 14a, 14b, 14c, 14d, and 14e have different frequencies, the positions of the sampling microphones 2a, 2b, 2c, 2d, and 2e can be easily distinguished.
[0049]
Moreover, since each sound wave generation means 14a, 14b, 14c, 14d, and 14e emits a sound wave at a mutually different timing, the position of each collection microphone 2a, 2b, 2c, 2d, and 2e can be distinguished easily.
[0050]
In calculating the distance between the sound wave generating means 14a, 14b, 14c, 14d, and 14e, that is, between the sampling microphones 2a, 2b, 2c, 2d, and 2e, a method for detecting a phase shift and sound There is a method of detecting the time to reach. When the sound wave generating means 14a, 14b, 14c, 14d, and 14e emit sound waves having different wavelengths, they can be measured simultaneously, but when the same sound is generated from different positions, different positions are available. Therefore, it is difficult to specify the sound generation position. Therefore, it is preferable that the sound wave generating means 14a, 14b, 14c, 14d, and 14e emit sound waves having different frequencies or emit sound waves at different timings. In addition, for example, when the sound wave has a characteristic waveform such as a peak value, it is easy to detect the time until the sound reaches.
[0051]
The respiratory sound data that is signal-processed by the signal processing means 3 may be wirelessly transmitted from the sampling microphones 2a, 2b, 2c, 2d, and 2e. As shown in FIG. 6, electrical signals collected by the sampling microphones 2a, 2b, 2c, 2d, and 2e are converted into radio waves by the transmission means 15a, 15b, 15c, 15d, and 15e, and transmitted from the antenna. This radio wave is extremely weak so as not to affect other medical devices. The radio waves transmitted from the transmission means 15a, 15b, 15c, 15d, and 15e are received by the reception means 16 and demodulated into electric signals. Then, the electric signal is converted into a digital signal by the A / D converter 17 and output to the I / O 10 of the signal processing means 3 in FIG.
[0052]
As the wireless method, various existing means can be used. Considering the medical field, in order to avoid damage to medical devices due to electromagnetic waves, those using light such as infrared rays and those using electromagnetic waves as typified by Bluetooth are preferable. When there is an obstacle between the transmission means 15a, 15b, 15c, 15d, 15e and the reception means 16, infrared rays or the like may become an obstacle to reception. In such a case, a signal is received at a position where there are few obstacles between the sampling microphones 2a, 2b, 2c, 2d, and 2e and transferred to the signal processing means 3 or received by a plurality of receiving means. A method of selecting, combining and using signals is used.
[0053]
In this way, by transmitting the respiratory sound data from the sampling microphones 2a, 2b, 2c, 2d, 2e to the signal processing means 3 wirelessly, the sampling microphones 2a, 2b, 2c, 2d, 2e and the signal processing means 3 are transmitted. No signal wiring is required to connect to and noise of respiratory sound data can be reduced. Further, complication of the medical site can be avoided, and handling of the sampling microphones 2a, 2b, 2c, 2d, and 2e becomes easy.
[0054]
It is also preferable to store respiratory sound data and analysis results in an electronic medical record. The storage in the electronic medical record can manage medical data in a centralized manner and can be used as a database for associating a disease with a respiratory sound. Furthermore, it contributes to the extraction of characteristic sounds and patterns for diseases, and can be used as a data source for improving the accuracy of diagnosis using the present invention.
[0055]
Moreover, the description in the said embodiment is an example of the suitable sound source location system which concerns on this invention, and is not limited to this. The detailed configuration and detailed operation of each part constituting the sound source position specifying system 1 can be appropriately changed without departing from the spirit of the present invention.
[0056]
【The invention's effect】
According to the first aspect of the present invention, since the relative position of each sound sampling means is calculated based on the sound wave generated by each sound wave generating means, the position of each sound source corresponding to each sound sampling means is accurately determined. Can be identified.
[0057]
According to the second aspect of the present invention, since the relative position of each sound sampling means on the human body is calculated, the body sound can be collected at the optimum collection position for each patient.
[0058]
According to the third aspect of the present invention, since each sound wave generating means emits a sound wave during the period in which the body sound is collected, the relative position of each sound collecting means at the time of the body sound collection can be calculated. it can.
[0059]
According to the fourth aspect of the present invention, since the sound waves generated by the sound wave generating means have different frequencies, the positions of the sound collecting means can be easily distinguished.
[0060]
According to the fifth aspect of the present invention, since each sound wave generating unit emits a sound wave at a different timing, the position of each sound collecting unit can be easily distinguished.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a sound source position specifying system 1 according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a functional configuration of the sound source position specifying system 1;
FIG. 3 is a diagram for explaining the structure of sampling microphones 2a, 2b, 2c, 2d, and 2e.
FIG. 4 is a flowchart showing respiratory sound signal processing executed by the sound source position specifying system 1;
FIG. 5 is a diagram for explaining a method of calculating the relative positions of four points A, B, C, and D where sampling microphones 2a, 2b, 2c, and 2d are located.
FIG. 6 is a diagram for explaining wireless transmission of respiratory sound data.
[Explanation of symbols]
1 Sound source location system 2a, 2b, 2c, 2d, 2e Respiratory sound collection microphone (sound collection means)
3 Signal processing means (calculation means)
4 Input means 5 Reproduction means 6 Display means 7 Print means 8 Database 9 CPU
10 I / O
11 ROM
12 RAM
13 storage means 14a, 14b, 14c, 14d, 14e sound wave generation means 15a, 15b, 15c, 15d, 15e transmission means 16 reception means 17 A / D converter

Claims (5)

In the sound source location system that identifies the location of the sound source corresponding to each of the plurality of sound sampling means,
Sound wave generating means for emitting sound waves respectively provided in the vicinity of each sound sampling means;
Calculation means for calculating the relative position of each sound sampling means based on the sound wave emitted by each sound wave generation means;
A sound source location system characterized by comprising: In the sound source location system according to claim 1,
The sound source position specifying system, wherein the plurality of sound collecting means collects a biological sound from a human body. The sound source location system according to claim 2,
The sound source position specifying system, wherein each sound wave generating means emits a sound wave during a period in which a body sound is collected by the plurality of sound collecting means. In the sound source localization system according to any one of claims 1 to 3,
The sound source position specifying system, wherein the sound waves generated by the sound wave generating means have different frequencies. In the sound source localization system according to any one of claims 1 to 4,
Each of the sound wave generating means emits sound waves at different timings.

Images