JP7251804B2 - Wearing device around the ear - Google Patents

Description

TECHNICAL FIELD The present invention relates to an ear-piercing device capable of detecting chewing and swallowing.

Chewing has various important functions, such as adjusting the physical properties of food to be suitable for swallowing and digestion, promoting saliva secretion and improving digestion, and stimulating the satiety center to prevent overeating and obesity.
However, due to changes in eating habits, the number of chewing cycles of modern people tends to decrease, and the relationship between the number of chewing cycles and lifestyle-related diseases has also been reported.
In addition, dysphagia and elderly people with impaired masticatory and swallowing functions are at high risk of suffocation and aspiration during meals, so it is necessary to carefully monitor their eating habits. However, until now, the main purpose of monitoring was to confirm the safety and survival of a person, and there were few that targeted monitoring during meals. Recording and managing meal histories is one of the important tasks in elderly care facilities, and watching meals is important in supporting care records and the like.
Therefore, in order to maintain health, prevent suffocation and aspiration, and record and manage meals, it is necessary to record “the state of chewing and swallowing, such as the number and pace of chewing and swallowing” and “the number of times of choking and coughing due to aspiration”. It is important to record and observe on a daily basis.
Patent Literature 1 proposes a mastication counter that detects and reports the user's mastication state by setting a target mastication condition with a simple operation according to the physical condition of the user, the type of food, and the like. In addition, in Patent Literature 1, a piezoelectric element is used to detect the movement of the user's mandible and upper cheekbone as chewing motion.
Patent Literature 2 proposes a dysphagia detection system that detects that no swallowing action has occurred. In this system, the mastication detection means detects that the subject continues to masticate, the movement detection means detects that the pharynx or larynx is not moving in a predetermined manner, and swallowing is detected. The disorder determination means determines that the subject has dysphagia based only on the two detection results of the mastication detection means and the movement detection means.
According to Patent Document 2, the mastication detection means is related to the sound in the mouth during mastication, the position of the jaw that moves during mastication of the subject, the myoelectric potential of the muscles involved in mastication of the subject, and the mastication of the subject. A physical quantity related to blood flow in blood vessels is detected, and the motion detection means includes a pressure sensor capable of measuring the position of the larynx of the subject, a distance measuring sensor, or a fluoroscopic image obtained by internally photographing the position of the pharynx of the subject. An imaging camera that captures and outputs is used.
Patent Literature 3 proposes a mastication frequency counter that measures the number of times of mastication by receiving the movement of the external auditory canal with an ear tip.
Patent Document 4 discloses a set of potential detection means for detecting potential generated by mastication, which is measured by potential detection means attached to the external auditory canals or auricles on both sides, respectively, and a set of potential detection means. proposed a mastication motion measuring device provided with a potential difference calculating means for calculating a difference in potential between the two.
Patent Literature 5 proposes a measuring device attached to a living body, which includes an ear hook portion that is held between the ear and the head and attached to the ear, and that can measure the number of times of mastication.
Patent Literature 6 proposes a muscle activity diagnostic device using an earphone-type sensor inserted into the ear canal, and specifies mastication as one of the muscle activity states of a person.
Patent Literature 7 proposes a detection device that includes a displacement sensor and a microphone to detect chewing and swallowing.

JP 2007-317144 A JP 2012-75758 A JP 2013-42968 A JP-A-2020-431 JP 2016-131854 A Japanese Patent Application Laid-Open No. 2012-228 WO2018/182043

In Patent Literature 1, the user can freely eat while the device is attached to the ear, but only chewing motions are detected, and swallowing cannot be detected.
Patent Document 2 describes detection of sound and myoelectric potential, both of which are used for mastication detection.
In Patent Document 3, a vibration sensor is used to measure the number of times of mastication.
In Patent Document 4, the device is attached to the auricle and detects chewing motion by myoelectric potential, but does not detect swallowing.
In Patent Document 5, the number of times of chewing is measured by detecting the movement of the lower part of the back of the ear using a distance measuring sensor, and swallowing is not detected.
In Patent Document 6, myoelectric potential is detected to identify mastication, and an earphone sensor is used, but swallowing is not detected.
In Patent Document 7, the displacement sensor is attached to the user's cheek or the like, and the microphone is attached to the user's temple or the like.
A device that can be worn around the ear is suitable for reducing the wearing burden on the wearer.

SUMMARY OF THE INVENTION An object of the present invention is to provide a wearable device around the ear that can accurately detect mastication and swallowing and is less burdensome to wear.

According to claim 1, the ear-piercing device of the present invention comprises biosignal detection means 10 and sound detection means 20, and includes temporal muscle, occipital muscle, sternocleidomastoid muscle, masseter muscle, auricular muscle, and stylohyoid bone. The biosignal detection means 10 is placed at a position where a biosignal due to muscle activity around the ear of at least one muscle of the digastric muscle and the digastric muscle can be detected, and the sound detection means is placed at a position where mastication sounds and swallowing sounds can be detected. 20, wherein a mastication interval is determined from the biosignal detected by the biosignal detection means 10, and an audio signal by the sound detection means 20 detected outside the determined mastication interval. to identify the swallowing sound.
According to a second aspect of the present invention, there is provided a device for wearing around the ear according to the first aspect, wherein the number of times of chewing is calculated from the biosignal detected in the mastication period, and the number of swallowing is calculated from the swallowing sound. and
According to the third aspect of the present invention, there is provided the ear-piercing device according to the first or second aspect, wherein the biosignal electrode 11 of the biosignal detection means 10 is brought into contact with the wearer's skin to detect the sound. It is characterized in that the microphone 21 of the means 20 is worn without contacting the skin of the wearer.
According to the fourth aspect of the present invention, in the ear-worn device according to the third aspect, the biosignal electrode 11 is arranged around the microphone 21, and the biosignal electrode 11 is attached to the wearer's skin. , an air layer 22 is formed between the microphone 21 and the skin.
According to a fifth aspect of the present invention, in the ear-worn device according to the fourth aspect, the biosignal electrodes 11 are arranged in a donut shape with the microphone 21 at the center.
According to the sixth aspect of the present invention, there is provided the ear-piercing device according to the third aspect, wherein the biosignal electrode 11 is arranged at a height higher than the Camper plane, and the microphone 21 is arranged at a height lower than the Camper plane. It is characterized in that it is arranged at
According to a seventh aspect of the present invention, in the ear-worn device according to any one of claims 1 to 6, a peak search is performed from the biological signal, and adjacent peaks detected by the peak search are The distance between the peaks is calculated as the mastication pace, the mastication strength is calculated using the height of the waveform of one of the peaks, and the muscle activity time is calculated using the width of the one peak at a predetermined height. The mastication interval is determined by removing the preparatory motion associated with swallowing using the mastication pace, the mastication strength, and the muscle activity time.

According to the ear-worn device of the present invention, the biosignal detection means is used to detect mastication, the sound detection means is used to detect swallowing, and the deglutition sound is detected by the biosignal detection means. By using the mastication section, mastication and swallowing can be accurately detected, and the burden of wearing is reduced by performing biosignal detection and sound detection by muscle activity around the ear.

FIG. 1 is a diagram showing an ear-piercing device and a mounting position of the device according to an embodiment of the present invention; A diagram showing the measurement points of a composite sensor for qualitative evaluation of biosignals Diagram showing qualitative evaluation results of biosignals FIG. 10 is a diagram showing detection points of biosignals in an experimental example of detection of mastication and swallowing; A diagram for explaining preprocessing of a detected biological signal. Figure showing mastication detection data in peak search Diagram showing mastication pace, mastication strength, and muscle activity time A diagram showing the mastication section by removing the preparatory motion Diagram showing swallow detection FIG. 4 is a diagram showing evaluation results of the ear-worn device according to the present embodiment. Mastication data by ingredients Diagram showing detection error due to detection position Diagram showing detection error due to detection position

The ear-mounted device according to the first embodiment of the present invention includes biosignal detection means and sound detection means, and includes temporal muscle, occipital muscle, sternocleidomastoid muscle, masseter muscle, auricular muscle, and stylohyoid bone. A biological signal detecting means is arranged at a position where a biological signal due to muscle activity around the ear of at least one muscle of the digastric muscle and the digastric muscle can be detected, and a sound detecting means is arranged at a position where mastication sounds and swallowing sounds can be detected. The ear-worn device determines a mastication period from a biological signal detected by a biological signal detection means, and specifies a swallowing sound from an audio signal detected by a sound detection means other than the determined mastication period. According to this embodiment, the biosignal detection means is used to detect mastication, the sound detection means is used to detect deglutition, and the mastication section detected by the biosignal detection means is used to specify the swallowing sound. By using the device, it is possible to accurately detect chewing and swallowing, and the burden of wearing the device is reduced because biosignal detection and sound detection due to muscle activity are performed around the ear.

According to the second embodiment of the present invention, in the ear support device according to the first embodiment, the number of times of chewing is calculated from the biosignal detected in the mastication period, and the number of swallowing is calculated from the sound of swallowing. . According to this embodiment, the number of chewing times and the number of swallowing times can be calculated accurately.

According to a third embodiment of the present invention, in the ear support device according to the first or second embodiment, the biosignal electrodes of the biosignal detection means are brought into contact with the wearer's skin, and the sound detection means The microphone is worn without contacting the wearer's skin. According to the present embodiment, by bringing the biosignal electrode into contact with the skin, the biosignal due to muscle activity can be accurately detected, while the noise generated by the microphone contacting the skin is prevented from coming into contact with the skin. By doing so, the swallowing sound can be detected accurately.

According to a fourth embodiment of the present invention, in the ear-worn device according to the third embodiment, the biosignal electrodes are arranged around the microphone, and the biosignal electrodes are brought into contact with the wearer's skin. An air layer is formed between the microphone and the skin. According to the present embodiment, by arranging the biosignal electrodes around the microphone, it is easy to form an air layer between the microphone and the skin, and the air layer enhances sound collection.

According to a fifth embodiment of the present invention, in the ear-worn device according to the fourth embodiment, the biosignal electrodes are arranged in a doughnut shape around the microphone. According to the present embodiment, it is easy to form an air layer with high sound collecting properties between the microphone and the skin.

According to a sixth embodiment of the present invention, in the ear-worn device according to the third embodiment, the biosignal electrode is arranged at a height higher than the Camper's plane, and the microphone is arranged at a height lower than the Camper's plane. It is arranged. According to this embodiment, mastication and swallowing can be detected more accurately.

According to a seventh embodiment of the present invention, in the ear-worn device according to any one of the first to sixth embodiments, a peak search is performed from the biosignal, and a peak between adjacent peaks detected by the peak search is The mastication pace is calculated by calculating the distance as the masticatory pace, calculating the masticatory strength using the height of one peak waveform, and calculating the muscle activity time using the width of one peak at a predetermined height. , mastication strength, and muscle activity time are used to remove preparatory motions associated with swallowing and determine mastication intervals. Preliminary motions are motions of closing the mouth and motions of bringing the upper and lower dentitions into occlusal contact during swallowing, and muscle activity is detected even in such preliminary motions. Elimination of the accompanying preparatory motion allows for more accurate detection of mastication segments, and the ability to accurately detect mastication segments allows for even more accurate detection of swallowing.

An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing an ear-surrounding fitting according to the present embodiment and a mounting position of the fitting.
The ear-worn device according to this embodiment includes biosignal detection means 10 and sound detection means 20 .
The biosignal detection means 10 is composed of a biosignal electrode 11, and the sound detection means 20 is composed of a microphone 21. The biosignal electrode 11 includes a reference electrode 11a for signal detection and an indifferent electrode (reference electrode) representing a reference potential. electrode) 11b.

As shown in FIG. 1( a ), the ear-mounted device according to the present embodiment has a biosignal electrode 11 of biosignal detection means 10 and a microphone 21 of sound detection means 20 arranged on a fixing member 30 . A composite sensor 1 is constructed. In FIG. 1(a), two Seki electrodes 11a as the biosignal electrodes 11 are arranged in a donut shape with the microphone 21 at the center. The number of Seki electrodes 11a may be one, or three or more. Further, the biosignal derivation method may be either a unipolar induction method or a bipolar induction method. For example, a two-channel biosignal may be derived from the signals observed by the two Seki electrodes 11a (unipolar induction). , one-channel biosignals may be derived (bipolar leads). By combining these, three-channel biosignals may be derived from two Seki electrodes 11a.
A rubber electrode is suitable for the biosignal electrode 11, and by using a rubber electrode, it can be used repeatedly, is flexible, and can be easily processed into an arbitrary shape. Another advantage is that the electrode position is less likely to shift during mastication and swallowing due to friction between the skin and the electrode.

As shown in FIG. 1(b), the biosignal electrode 11 is brought into contact with the wearer's skin, and the microphone 21 is worn without being brought into contact with the wearer's skin. When the biosignal electrode 11 is arranged around the microphone 21 and the biosignal electrode 11 is in contact with the wearer's skin, an air layer 22 is formed between the microphone 21 and the skin. It is preferable to provide a ring-shaped silicon material 23 around the formed air layer 22 . Instead of the silicon material 23, a mesh insulator or a sponge material that does not affect sound collection may be used on the surface of the microphone 21. FIG.

A region X shown in FIG. 1(c) indicates a range in which the biological signal detection means 10 and the sound detection means 20 are arranged when the device is worn. Although FIG. 1(c) shows two composite sensors 1A and 1B as the composite sensor 1, it merely shows the arrangement, and any one of the composite sensors 1 may be used. In FIG. 1(c), the indifferent electrode 11b is placed behind the earlobe.

The biosignal detection means 10 detects a biosignal by muscle activity around the ear of at least one of the temporalis muscle, the occipital muscle, the sternocleidomastoid muscle, the masseter muscle, the auricular muscle, the stylohyoid muscle, and the digastric muscle. Place it in a position where it can be detected. In this embodiment, biosignals due to muscle activity are described as myoelectric potential signals. A pressure signal and a displacement signal for detecting are also biological signals due to muscle activity.
The sound detection means 20 is arranged at a position where chewing sounds and swallowing sounds can be detected.
By detecting biosignals around the ear by the biosignal detection means 10 and the sound detection means 20 in this way, the ear-wound device according to the present embodiment can be used like an ear-hook type device or a spectacle-type device. It can be a wearable device that can be used on a daily basis.

In addition to the biological signal detection means 10 and the sound detection means 20, the ear-wound device according to the present embodiment includes an amplifier that amplifies the detection signal, an AD converter that performs analog-to-digital conversion, a power supply section that supplies power, and a detection signal. is provided. These amplifiers, AD converters, power supply units, and control units may be arranged around the ear together with the biological signal detection means 10 and the sound detection means 20, but by providing wired or wireless communication means, these Some or all may be structurally separated.
The ear-mounted device according to the present embodiment can accurately detect myoelectric potentials by bringing the biosignal electrode 11 into contact with the skin, while noise can be reduced by not bringing the microphone 21 into contact with the skin, and the swallowing sound can be accurately detected. can be detected.
In addition, in the ear-worn device according to the present embodiment, by arranging the biosignal electrodes 11 around the microphone 21, the air layer 22 is easily formed between the microphone 21 and the skin, and the air layer 22 collects enhances sound. By arranging the biosignal electrodes 11 in a donut shape with the microphone 21 at the center, it is easy to form an air layer 22 with high sound collecting properties between the microphone 21 and the skin.

The following equipment was used in the following experiments.
The composite sensor 1 consists of a biosignal electrode 11 and a microphone 21. The biosignal electrode 11 is a "biosignal rubber electrode" (manufactured by NOK Corporation), and the microphone 21 is a "microphone (EM-60340BT-A). ” (manufactured by Aoi Denki) was used.
The microphone 21 is driven by a single 5V power supply with 2.5V as the potential reference. A voice signal from the microphone 21 is amplified five times by a microphone amplifier and is taken into an AD converter.
A myoelectric potential signal (biological signal) from the biosignal electrode 11 was measured by performing differential amplification with reference to the indifferent electrode 11b attached to the earlobe. The myoelectric potential signal detected is amplified by 2,052 times through the myoelectric amplifier box and taken into the AD converter.
In the measurement, analog input was used to acquire data, and NIUSB-6218 (NATIONAL INSTRUMENTS) was used as an AD converter used for data acquisition. The sampling frequency was set to 8 kHz, which is double the frequency band up to 4 kHz, where the characteristics of swallowing are observed.
When the bipolar lead method is used for deriving the myoelectric potential signal, the signal obtained by one composite sensor 1 is one channel for the myoelectric potential signal and one channel for the audio signal.

FIG. 2 is a diagram showing measurement points of a composite sensor for qualitative evaluation of biosignals.
FIG. 3 is a diagram showing qualitative evaluation results of biosignals.

FIG. 3(a) shows measurement data on the right ear side when chewing rice on the right side. The illustrated myoelectric potential signal is the myoelectric potential signal for each composite sensor 1 .
As shown in FIG. 3(a), myoelectric potential signals during clenching were observed at all locations around the ear. In addition, myoelectric potential signals corresponding to preparatory movements for swallowing were observed before swallowing.

FIG. 3(b) shows measurement data on the right ear side when chewing rice on the right side, which is an audio signal for one channel of the microphone 21 for each composite sensor 1. FIG.
As shown in FIG. 3(b), chewing sounds were obtained at all locations around the ears. In the lower part of the ear, the mastication sound was observed to become smaller as it went down. Swallowing sounds were also observed below the ear. Swallowing sounds tended to be louder at the lower ear (2). It is considered that the sound signal is greatly affected by the position where the sound is generated.
In terms of qualitative evaluation, if mastication is located in the temporalis muscle above the ear, a large waveform can be obtained. However, muscle activity during occlusal contact (hereinafter referred to as preparatory movement) that brings the upper and lower tooth surfaces together during swallowing is also observed, and advanced signal processing such as machine learning is required to distinguish mastication and swallowing from myoelectric potential signals alone. . Audio signals can detect chewing, but can detect swallowing closer to the pharynx.

FIG. 3(c) shows the myoelectric potential signal and the audio signal when the food and the subject are different.
As shown in FIG. 3(c), the muscle activity varies depending on the foodstuff, and there are individual differences. Even for the same subject, when the electrode positions are different, the waveform of the muscle activity differs.
Therefore, machine learning and threshold processing are generally required to detect mastication from myoelectric potential signals. However, machine learning requires learning data, and even if it is technically possible, it is not realistic to prepare mastication data for various ingredients in advance. This is the same in the case of threshold processing, and it is necessary to consider differences in ingredients, individual differences, and differences in measurement positions.
Moreover, even with the same foodstuff, the muscle activity changes as the bite size, mastication progresses, and bolus formation progresses. Furthermore, there is a preparatory action associated with swallowing, and it is difficult to distinguish between mastication and preparatory action. In addition, there are cases where the preparatory motion does not appear depending on the swallowing conditions, such as when drinking a lot of water from a plastic bottle, and it is necessary to determine the motion.

FIG. 4 is a diagram showing biosignal detection points in an experimental example of detection of mastication and swallowing.
A total of six composite sensors 1 were attached to the left and right sides of the face and measurements were taken. The signals obtained are 6 channels of myopotential signals and 6 channels of audio signals.
In order to determine the measurement points of the composite sensor 1, the reference used in the dental field, namely the Camper's plane, was used. The Camper plane is a plane formed by a line connecting the tragus point and the nasal point. A line that is perpendicular to the Camper's plane and intersects with the tragus point is used as a reference, and the measurement points of the sensor are 15 mm upward and 50 mm and 80 mm downward from the Camper's plane.
The combined sensor 1A at a position 15 mm upward from the Camper's plane is mainly located at the temporalis muscle, which is the muscle of mastication, and the combined sensors 1B and 1C at positions 50 mm and 80 mm downward from the Camper's plane are mainly located at the sternocleidomastoid muscle. It is thought that

FIG. 5 is a diagram for explaining the preprocessing of detected biological signals.
As preprocessing for reducing noise, an 800 Hz low-cut filter is applied to the myoelectric potential signal and a 900 Hz low-cut filter is applied to the voice signal. After that, in performing signal processing, the measured signal is divided into frames of length 64 ms, and calculation is performed for each frame.
As shown in FIG. 5(a), when moving the calculation range from one frame to the next, a frame shift method was adopted in which the start point of the frame is shifted at intervals of 12 ms.

In order to detect mastication/swallowing, it is necessary to make the waveform signal easy to detect. Here, S in the formulas shown in FIGS. 5(b) and 5(c) represents a measurement signal (Signal).
In order to extract the characteristics of the amplitude component in the time domain of the signal, the RMS (Root Mean Square) shown in FIG. 5(b) was obtained for each frame. In general, when measuring the muscle activity of the same muscle, the stronger the muscle contraction, the higher the RMS value. Therefore, the greater the RMS value, the greater the muscle activity required for mastication, that is, the information on the strength of mastication can be obtained. Here, the value of the n-th sample measurement signal S in the p-th frame at the channel number l (l=1, 2, . . . , 6) is S _l,n (p) (n=1, 2, , N). When the frame length is 64 ms and the sampling frequency is 8,000 Hz, the sample number N of the frame is 512 points.
In addition, the RMS feature amount was subjected to moving average processing according to the formula shown in FIG. 5(c) in order to suppress variations between frames. p is the frame number and M is the number of moving averages. This time, M=10.
The above processing was performed for each channel.

FIG. 6 is a diagram showing mastication detection data in peak search.
Mastication is detected from the preprocessed myoelectric potential signal using peak search to avoid the effects of food, sensor position, and individual differences. “▼” shown in FIG. 6 are peaks actually detected as mastication. FIG. 6A shows data in which the preparatory motion is not detected as a peak, and FIG. 6B shows data in which the preparatory motion is detected as a peak.

FIG. 7 is a diagram showing chewing pace, chewing strength, and muscle activity time.
The masticatory pace is calculated as the distance between adjacent peaks detected by peak search, the masticatory strength is calculated using the height of the waveform of one peak, and the muscle activity time is calculated as the predetermined length of one peak. Calculated using width at height.
In FIG. 7, the muscle activity time is the width at half the peak height. The masticatory strength can also be an area obtained by integration from the waveform and width determined by one peak.

8A and 8B are diagrams showing the mastication section with the preparatory motion removed, FIG. 8A showing the masticatory section including the preparatory action, and FIG. 8B showing the masticatory section after the preparatory action is removed. is shown.
The mastication pace, mastication intensity, and muscle activation time shown in FIG. 7 are used to remove preparatory movements from the mastication segment.
As shown in FIG. 8(a), when the preparatory motion is detected as a peak, the mastication section including the preparatory motion is defined only by the peak search result. The muscle activation time is used to identify the preparatory motion. For example, when the average values of mastication pace, mastication strength, and muscle activity time are calculated, and the average value is multiplied by a coefficient for determination, the average mastication pace x 1.6 or more, the average mastication strength x If either 0.4 or less or the average of muscle activity times×1.3 or more is satisfied, it can be determined as a preparatory motion.
As shown in FIG. 8(b), the correct chewing interval can be obtained by removing the preparatory movement.
In this way, by using the calculated mastication pace, mastication strength, and muscle activity time to determine the mastication interval by removing the preliminary motion associated with swallowing, the mastication interval can be detected more accurately. can be accurately detected, swallowing can also be detected more accurately.
The number of times of mastication can be calculated from the peak in the determined mastication section.

FIG. 9 is a diagram showing detection of swallowing.
The swallowing sound is detected using the mastication interval.
FIG. 9(a) shows the detected myoelectric potential signal and the audio signal.
The audio signal is masked in the determined mastication interval (FIG. 9(b)). Since mastication sounds are generated later than the peak of mastication muscle activity, it is preferable that the mask has a wider range than the actual mastication interval. Note that swallowing may occur multiple times.
The ear-mounted device according to this embodiment determines a mastication segment from the myoelectric potential signal detected by the biosignal detection means 10, and specifies the swallowing sound from the sound signal detected by the sound detection means 20 other than the determined mastication segment. do.
Here, the audio signal that can be identified as the swallowing sound can be detected between the determined first mastication segment and the second mastication segment determined at the next timing of the first mastication segment as other than the mastication segment. . Also, a predetermined time after the first mastication interval and a predetermined time after the second mastication interval can be detected as other than the mastication interval.
In this manner, the biosignal detection means 10 is used to detect mastication, the sound detection means 20 is used to detect deglutition, and the mastication interval detected by the biosignal detection means 10 is used to specify the swallowing sound. Thus, chewing and swallowing can be accurately detected.
Further, by calculating the number of times of mastication from the myoelectric potential signal detected in the mastication interval and calculating the number of times of swallowing from the swallowing sound, the number of times of chewing and the number of times of swallowing can be calculated accurately.
In addition, in the mastication period detection process, if the preliminary motion can be identified by detecting the preliminary motion as a peak as shown in FIG. By specifying it as sound, it is possible to improve the accuracy of swallowing detection.

FIG. 10 is a diagram showing evaluation results of the ear-worn device according to the present example.
The error was calculated and evaluated by the formula shown in FIG. 10(a). The error (outlier rate) is the error in the estimated number of times, and the correct number of times is the number of times recorded by the subject's self-report.
In the evaluation experiment, in addition to gummies and gum, which are often used in chewing experiments, we used rice crackers to make a sound when chewing, and rice, which is a staple food. In addition, the amount and size of the foodstuffs were adjusted so that the number of times of mastication was about 10 times in a preliminary experiment.
For rice, 5g of co-op product “Oishii Gohan”, for rice crackers, 1 sheet of “Tsu no Edamame” Kameda Seika, for gummies, 1/2 gummy “Tsubugumi” Kasugai Seika Co., Ltd., for gum “ACUO” Lotte Co., Ltd. One grain was used.
The error shown in FIG. 10(b) is that four subjects define one set as "right biting about 10 times → left biting about 10 times→left biting about 10 times→swallowing once", and perform 6 sets of each. is the average error of

Fig. 11 shows mastication data for each ingredient, Fig. 11(a) shows mastication intensity, Fig. 11(b) shows mastication pace, Fig. 11(c) shows mastication time, and Fig. 11(d) shows time from completion of mastication to swallowing. FIG. 4 is a diagram showing time;
As shown in FIG. 11, it can be seen that chewing intensity and chewing time are large for chewy gummies. In this way, the characteristics of meals can be quantified.

12 and 13 are diagrams showing detection errors depending on detection positions.
12(a) to 12(d) and FIG. 13(a), a total of six composite sensors 1A, 1B, and 1C shown in FIG. are different. In FIGS. 13(b) to 13(d), a total of four composite sensors 1A and 1B shown in FIG. 4 are attached to the left and right sides of the face, and different composite sensors 1 are used for measurement.
In FIG. 12(a), two channels of myoelectric potential signals from the combined sensor 1A placed on the right side of the face and the combined sensor 1A placed on the left side of the face are used, and the combined sensors 1B and 1C placed on the right side of the face and Four audio signal channels from the arranged composite sensors 1B and 1C are used.
In FIG. 12(b), the combined sensors 1A, 1B, and 1C placed on the right side of the face and the combined sensors 1A, 1B, and 1C placed on the left side of the face are used for six channels of myoelectric potential signals, and the combined sensor placed on the right side of the face 6 channels of audio signals from 1A, 1B, 1C and composite sensors 1A, 1B, 1C placed on the left side of the face are used.
In FIG. 12(c), two channels of myoelectric potential signals from the combined sensor 1A placed on the right side of the face and the combined sensor 1A placed on the left side of the face are used, and the combined sensor 1C placed on the right side of the face and the left side of the face Two audio signal channels from the composite sensor 1C are used.
In FIG. 12(d), the myoelectric potential signal channel 1 from the combined sensor 1A placed on the right side of the face is used, and the audio signal channel 1 from the combined sensor 1C placed on the right side of the face is used.

In FIG. 13A, one channel of the myoelectric potential signal from the combined sensor 1A placed on the left side of the face is used, and one channel of the sound signal from the combined sensor 1C placed on the left side of the face is used.
In FIG. 13(b), using two channels of myoelectric potential signals from the combined sensor 1A placed on the right side of the face and the combined sensor 1A placed on the left side of the face, the combined sensor 1B placed on the right side of the face and the left side of the face Two audio signal channels from the composite sensor 1B are used.
In FIG. 13(c), one channel of myoelectric potential signals from the combined sensor 1A placed on the right side of the face is used, and one channel of audio signals from the combined sensor 1B placed on the right side of the face is used.
In FIG. 13D, one channel of the myoelectric potential signal from the combined sensor 1A placed on the left side of the face is used, and one channel of the sound signal from the combined sensor 1B placed on the left side of the face is used.
As shown in FIGS. 12 and 13, although the detection error is small in both cases, the biosignal electrode 11 is arranged at a height above the Camper's plane, and the microphone 21 is arranged at a height below the Camper's plane. This facilitates accurate detection of mastication and swallowing.

The present invention does not require calibration or machine learning learning processes, and can detect chewing and swallowing regardless of ingredients, individual differences, and differences in measurement positions.

Reference Signs List 1 compound sensor 1A compound sensor 1B compound sensor 1C compound sensor 10 biosignal detection means 11 biosignal electrode 11a interest electrode 11b indifference electrode 20 sound detection means 21 microphone 22 air layer 23 silicon material 30 fixing member X area

Claims (7)

comprising biosignal detection means and sound detection means,
The living body at a position where a biological signal can be detected by muscle activity around the ear of at least one of the temporal muscle, occipital muscle, sternocleidomastoid muscle, masseter muscle, auricular muscle, stylohyoid muscle, and digastric muscle. arranging a signal detection means,
An ear-mounted device in which the sound detection means is arranged at a position where mastication sounds and swallowing sounds can be detected,
determining a mastication interval from the biosignal detected by the biosignal detection means;
An ear-surrounding wearing device, characterized in that the swallowing sound is specified by an audio signal detected by the sound detection means detected outside the determined mastication interval. calculating the number of times of mastication from the biosignal detected in the mastication interval;
2. The ear-piercing device according to claim 1, wherein the number of swallows is calculated from the swallowing sound. bringing the biosignal electrode of the biosignal detection means into contact with the wearer's skin;
3. The ear-worn device according to claim 1, wherein the microphone of said sound detecting means is worn without contacting said skin of said wearer. arranging the biosignal electrode around the microphone;
4. The ear-piercing device according to claim 3, wherein an air layer is formed between the microphone and the skin when the biosignal electrode is in contact with the skin of the wearer. 5. The ear-worn device according to claim 4, wherein the biosignal electrodes are arranged in a doughnut shape around the microphone. The biosignal electrode is arranged at a height above the Camper's plane,
4. The ear-worn device according to claim 3, wherein the microphone is arranged at a height equal to or lower than the Camper's plane. Performing a peak search from the biosignal,
Calculate the distance between adjacent peaks detected by the peak search as a mastication pace,
Calculate the mastication strength using the waveform height of one of the peaks,
calculating the muscle activity time using the width at a predetermined height of one of the peaks;
7. The mastication interval is determined by removing preparatory movements associated with swallowing using the calculated mastication pace, mastication strength, and muscle activity time. 1. The ear-periphery fitting according to 1.

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