JPWO2018216362A1 - Care support system - Google Patents

Abstract

The care support system includes a sensor unit, a radiation control unit, and a storage unit. The sensor unit is arranged in a housing of a moving object detection unit installed in a living room of the subject, and detects biological information of the subject by emitting and receiving radio waves. The storage unit stores a table that defines a specific radiation frequency such that a noise level detected by the sensor unit is lower than a predetermined level at which biological information can be detected for each of different directions of the sensor unit in the housing. I do. The radiation control unit switches the radiation frequency of the radio wave radiated from the sensor unit to a specific radiation frequency corresponding to the direction of the sensor unit, which is obtained based on the table, according to the setting of the direction of the sensor unit.

Description

  The present invention provides a care support system in which a sensor unit disposed in a housing of a moving object detection unit installed in a living room of a subject detects biological information (for example, a respiratory state) of the subject by emitting and receiving radio waves. It is about.

  2. Description of the Related Art Conventionally, various Doppler sensors have been proposed that detect the movement of an object by radiating radio waves toward the object, receiving reflected waves that are reflected by the object and Doppler shifted. In such a Doppler sensor, in order to increase the detection accuracy, it is necessary to reduce unnecessary noise called clutter (reflected waves from objects other than the detection target) as much as possible. Therefore, for example, in Patent Literature 1, a signal obtained in a state where no detection target object exists (a state where only clutter exists) and a signal obtained in a state where a detection target object exists (a state where an object and clutter exist) are obtained. By taking the difference from the signal, a clutter signal which becomes noise is removed.

JP-A-2006-3289 (see claim 1, paragraphs [0022], [0023], etc.)

  In recent years, the state of a subject has been detected using a Doppler sensor (hereinafter also referred to as a sensor unit) for the purpose of supporting the daily life of the subject, such as a care recipient, in a care facility or a hospital. However, a care support system that manages this on a server is being used. In such a care support system as well, it is desired to increase the detection accuracy of the sensor unit, but at this time, applying the method of Patent Document 1 described above is not appropriate for the following reasons.

  The method described in Patent Document 1 is effective only when a signal to be observed (a reflected wave from an object) is larger than a clutter signal. If the signal to be observed is smaller than the clutter signal, the signal to be observed is buried in the clutter signal. Therefore, if the subtraction processing is performed, the signal to be observed cannot be detected. In particular, in nursing homes, the elderly are often occupied, and in the case of the elderly, the signal detected by the sensor unit (for example, a respiratory signal) is smaller than that of middle-aged or young people. Therefore, the signal to be observed (respiration signal) is often smaller than the clutter signal. Therefore, in the care support system, a method of removing a clutter signal by a subtraction process cannot be adopted.

  Also, many nursing homes spend most of their day in their living rooms due to reasons such as the elderly and physical disabilities. For this reason, in a care support system constructed in a nursing facility, it is not possible to freely create a situation in which there is no cared person in the living room and only clutter exists. For this reason, in the use of the care support system, it is difficult to use the method of Patent Document 1 in which a situation where only clutter exists is intentionally created and the subtraction process is performed.

  In the care support system, the sensor unit (Doppler sensor) is covered with a housing, and is installed, for example, on the ceiling of a living room. Then, the orientation of the sensor unit is usually adjusted so as to face the direction of the bed or the futon in the living room (to detect the respiratory state while sleeping). When the orientation of the sensor unit is adjusted, the relative positional relationship (for example, relative distance) between the sensor unit and the housing in front of the sensor unit changes. Therefore, when the radiation frequency of the radio wave radiated from the sensor unit is fixed, Depending on the direction of the unit, unnecessary reflected waves (clutter) radiated from the sensor unit and reflected on the inner surface of the housing and returning to the sensor unit increase, and the detection performance varies depending on the direction of the sensor unit. Therefore, no matter what direction the sensor unit is set, it is desired to suppress an increase in noise due to a change in the relative position with respect to the housing, and to suppress variation in detection performance due to the direction of the sensor unit.

  SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to reduce the clutter which becomes noise without performing a subtraction process of a clutter signal and to perform detection accuracy in a sensor unit (Doppler sensor). Another object of the present invention is to provide a care support system capable of suppressing variations in detection performance due to the orientation of the sensor unit, while increasing the accuracy of the sensor.

  A care support system according to one aspect of the present invention is disposed in a housing of a moving object detection unit installed in a living room of a subject, and a sensor unit that detects biological information of the subject by emitting and receiving radio waves, A radiation control unit that controls the radiation frequency of the radio wave, and for each different direction of the sensor unit in the housing, the noise level detected by the sensor unit is higher than a predetermined level at which the biological information can be detected. A storage unit that stores a table that defines a specific radiation frequency to be reduced, wherein the radiation control unit determines a radiation frequency of the radio wave radiated from the sensor unit according to a setting of an orientation of the sensor unit. And switching to the specific radiation frequency corresponding to the direction of the sensor unit, which is obtained based on the table.

  In the care support system, it is possible to reduce the clutter that becomes noise and improve the detection accuracy in the sensor unit without performing post-processing of the clutter signal subtraction process, and to suppress the variation in the detection performance due to the orientation of the sensor unit. .

FIG. 1 is an explanatory diagram illustrating a schematic configuration of a care support system according to an embodiment of the present invention. It is explanatory drawing which shows typically the state in the living room where the moving body detection unit of the said care support system was installed. It is explanatory drawing which shows typically the state in the living room where the 2nd electric wave detection part was installed. It is a block diagram showing a schematic structure of the above-mentioned moving body detection unit. FIG. 3 is a block diagram illustrating a detailed configuration of an optical detection unit included in the moving object detection unit. It is explanatory drawing which shows typically an example of the image acquired by imaging | photography by the said optical detection part. It is sectional drawing of the said moving body detection unit and the electric wave detection part in the attachment state of the front cover of the housing | casing of the said moving body detection unit, and the detached state, respectively. FIG. 5 is an explanatory diagram illustrating an example of a Fourier transform spectrum of a detection signal when nobody is present, output from the radio wave detection unit. It is explanatory drawing which shows the Fourier-transform spectrum of a detection signal at the time of detecting the respiratory state of a care receiver. FIG. 7 is an explanatory diagram schematically illustrating a generation path of a clutter signal generated inside the moving object detection unit illustrated in FIG. 6. FIG. 4 is an explanatory diagram schematically showing a relationship between a magnitude of a respiratory signal detected by a sensor unit of the radio wave detection unit and a noise level. FIG. 4 is an explanatory diagram showing a Fourier transform spectrum of a signal detected by the sensor unit when the driver is unattended, for each of large and small clutter signals. FIG. 4 is an explanatory diagram showing a Fourier transform spectrum of a detection signal of the sensor unit when a clutter signal is larger than a power level of a respiration signal. FIG. 3 is an explanatory diagram for explaining a wave interference phenomenon. It is explanatory drawing which shows the direction of the said sensor part changed according to the position of several beds in a living room. FIG. 4 is an explanatory diagram illustrating an example of a relationship between a radome angle and a noise level. It is explanatory drawing which shows each waveform of a transmission wave, a reflected wave, and a synthetic wave when the radiation frequency of a transmission wave is changed typically. It is explanatory drawing which shows the radome angle dependence of the noise level in different radiation frequencies. FIG. 3 is a block diagram illustrating a configuration of a care support system of a specific example 1. It is explanatory drawing which shows an example of the table memorize | stored in the memory | storage part of the said care support system. FIG. 18 is an explanatory diagram illustrating an example of a specific radiation frequency obtained based on the radome angle dependence of the noise level illustrated in FIG. 17. It is explanatory drawing which shows the other example of the said specific radiation frequency. It is a block diagram which shows the structure of the care support system of the example 2. FIG. 14 is an explanatory diagram illustrating an example of a table stored in a storage unit in the care support system of Example 3;

  One embodiment of the present invention will be described below with reference to the drawings.

[Outline of care support system]
FIG. 1 is an explanatory diagram showing a schematic configuration of a care support system 1 of the present embodiment. The care support system 1 is a system for supporting the daily life of a cared person who lives in a nursing facility or a general house or a patient (a cared person) who is admitted to a hospital, and is also called a watching system. Have been. The cared person and the cared person are the objects to be supported by the care support system 1, that is, the objects (objects) managed by recognition and detection by the image recognition system 20 and the radio wave detection unit 30, which will be described later. . Here, as an example, a case where the care support system 1 is constructed in a care facility will be described.

  In the nursing facility, a staff station 100 and a living room 101 are provided. The staff station 100 is a so-called cramming place for a caregiver who supports the life of a care receiver who spends time in a care facility. The staff station 100 includes a management server 100a and a display unit 100b. The management server 100a is a terminal device communicably connected to a below-described moving object detection unit 10 installed in the living room 101 via the communication line 200, and includes a central processing unit (CPU). Be composed. Note that the communication line 200 is, for example, a wired LAN (Local Area Network), but may be a wireless LAN.

  The management server 100a receives and manages various types of information (for example, captured images in the living room 101 and biological information of the cared person) transmitted (output) from the moving body detection unit 10 via the communication line 200, A process for displaying the received information on the display unit 100b is performed. Thereby, the caregiver of the care facility can see the information displayed on the display unit 100b and grasp the state in the living room 101 and the biological information of the care receiver. The display unit 100b can be configured by, for example, a display of a personal computer. Further, when it is recognized by the image recognition processing in the image recognition system 20 that will be described later that the care receiver's operation is abnormal, such as when the care receiver falls down on the floor, the management server 100a executes the moving object detection unit. 10 to the mobile terminal owned by the caregiver to transmit the data of the captured image in the living room 101 acquired by the optical detection unit 23 of the moving body detection unit 10 to the caregiver. To the caregiver. When the image data is transmitted from the management server 100a to the portable terminal, the size and resolution of the image are appropriately adjusted.

  At least one living room 101 is provided in a nursing home, and FIG. 1 shows a case where two living rooms 101 are provided as an example. In each living room 101, one bed 102 used by the care receiver is installed. When two or more care receivers enter one living room 101, a plurality of beds 102 corresponding to each of the care receivers are installed.

  FIG. 2 is an explanatory diagram schematically showing a state in the living room 101 in which the moving object detection unit 10 is installed. As shown in FIGS. 1 and 2, the moving body detection unit 10 is installed on a ceiling 101 a of each living room 101 and is communicably connected to a communication line 200. When the living room 101 is a multi-bed room where a plurality of beds 102 are installed, the moving body detection unit 10 is installed on the ceiling 101 a of the living room 101 in correspondence with each bed 102.

  The above-described care support system 1 connects the moving object detection unit 10 (at least one moving object detection unit 10) installed in at least one living room 101 and the management server 100a provided in the staff station 100 via the communication line 200. And are communicably connected.

[Motion detection unit]
Next, details of the moving object detection unit 10 will be described. FIG. 3 is a block diagram illustrating a schematic configuration of the moving object detection unit 10. The moving body detection unit 10 is a unit that detects information of a cared person in the living room 101, and includes an image recognition system 20, a radio wave detection unit 30, and a unit control unit 40 in a housing 11 (see FIG. 6). I have. The moving object detection unit 10 is also called a sensor box because it includes various sensors such as the above-described radio wave detection unit 30 and an optical detection unit 23 described later.

  The image recognition system 20 includes an illumination unit 21, an illumination control unit 22, and an optical detection unit 23. The lighting unit 21 is configured to include an LED (Light Emitting Diode) that emits infrared light (for example, near-infrared light) so as to enable imaging in the dark, and is provided at the center of the ceiling 101 a of the living room 101. To illuminate the interior of the living room 101. For example, the illumination unit 21 has a plurality of LEDs, and illuminates a floor surface 101b (see FIG. 2) in the living room 101 and a wall connecting the ceiling 101a and the floor surface 101b. The illumination control unit 22 includes, for example, a CPU and controls illumination (infrared light emission) by the illumination unit 21.

  The optical detection unit 23 is an imaging unit that captures an image by photographing the inside of the living room 101 under the illumination of the illumination unit 21, and includes, for example, a camera. FIG. 4 is a block diagram illustrating a detailed configuration of the optical detection unit 23. FIG. 5 schematically illustrates an example of an image obtained by photographing with the optical detection unit 23. The optical detection unit 23 is disposed adjacent to the illumination unit 21 at the center of the ceiling 101a (see FIG. 2) of the living room 101, and obtains an image of a viewpoint directly above the viewing direction by shooting. The optical detection unit 23 includes a lens 51, an imaging element 52, an AD conversion unit 53, an image processing unit 54, and a control calculation unit 55.

  The lens 51 is, for example, a fixed focus lens, and is configured by a general super wide angle lens or a fisheye lens. As the ultra-wide-angle lens, a lens having a diagonal angle of view of 150 ° or more can be used. As a result, as shown in FIG. 5, the entire living room 101 can be photographed from the ceiling 101a, and the cared person in the room and the entire room can be photographed without blind spots.

  The imaging element 52 is configured by an image sensor such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). The image sensor 52 is configured by removing the IR cut filter so that the state of the care receiver can be detected as an image even in a completely dark environment. An output signal from the image sensor 52 is input to the AD converter 53.

  The AD converter 53 receives an analog image signal of an image captured by the image sensor 52 and converts the analog image signal into a digital image signal. The digital image signal output from the AD conversion unit 53 is input to the image processing unit 54.

  The image processing unit 54 receives a digital image signal output from the AD conversion unit 53, and performs image processing such as black correction, noise correction, color interpolation, and white balance on the digital image signal. . The image-processed signal output from the image processing unit 54 is input to an image recognition unit 25 described below.

  The control calculation unit 55 executes calculations such as AE (Automatic Exposure) related to control of the image sensor 52 and controls the exposure time and gain of the image sensor 52. Further, the control calculation unit 55 executes calculations such as a suitable light amount setting and a light distribution setting for the illumination unit 21 as necessary, and also executes control. Note that the control calculation unit 55 may have the function of the illumination control unit 22 described above.

  The image processing unit 54 and the control calculation unit 55 are configured by, for example, separate CPUs, but may be integrally configured by one CPU, or may be configured by dedicated circuits for performing image processing and calculation processing. May be done.

  The above-described image recognition system 20 further includes a storage unit 24 and an image recognition unit 25.

  The storage unit 24 is a memory that stores a control program executed by the unit control unit 40 and various types of information, and includes, for example, a random access memory (RAM), a read only memory (ROM), and a nonvolatile memory.

  The image recognition unit 25 performs an image recognition process on the image data of the image acquired by the optical detection unit 23. More specifically, the image recognizing unit 25 receives the signal after the image processing unit 54 of the optical detection unit 23 has executed the image processing, extracts the contour of the object, and shapes the object by a method such as pattern matching. Image recognition processing for recognizing is performed. Thus, the image recognition unit 25 can recognize the state of the care receiver in the living room 101.

  Here, as the state of the care receiver in the living room 101, wake-up, leaving the bed, entering the floor, falling down, and the like are assumed. Waking up refers to the state from when the cared person wakes up to when he / she wakes up on the bed. Leaving the bed refers to a state in which the care receiver raises his / her body on the bed and then goes down to the floor and separates from the bed. Entering the bed refers to an operation in which the care receiver goes up from the floor to the bed and lays down. Falling refers to the action of the care receiver falling on the floor. The above-mentioned wake-up, leaving, entering, and falling are accompanied by size movements (body movements) of the body of the cared person, and are detected by the radio wave detection unit 30 (fine movements of the body due to respiration, etc.). ).

  Note that the image recognition unit 25 can also recognize the shape and position of the bed 102 and the futon in the living room 101 by image recognition.

  The radio wave detection unit 30 is a block that detects a moving object in the living room 101 by radiating and receiving radio waves. The radio wave detection unit 30 radiates, for example, a 24 GHz band microwave toward a bed in each living room from a radiation unit (not shown). The reflected wave reflected by and Doppler shifted is received by a receiving unit (not shown). Thereby, the radio wave detection unit 30 can detect the living body information (information such as a respiratory state, a sleep state, and a heart rate) of the care receiver from the received reflected wave.

  Note that when the care receiver is breathing (including during sleep), a minute movement (small body motion) of the body due to the care recipient's breathing occurs. Therefore, detecting the respiratory state or sleep state of the cared person is the same as detecting the minute body movement of the cared person. From this, it can be said that the radio wave detection unit 30 functions as a micro body movement detection unit that detects the micro body movement of the care receiver (the subject).

  The unit control unit 40 controls the operations of the image recognition system 20 and the radio wave detection unit 30, performs image processing and signal processing on the information obtained from the image recognition system 20 and the radio wave detection unit 30, and obtains the obtained result. Is output to the management server 100a as information on the state of the cared person. The unit control unit 40 includes a main control unit 41, an information processing unit 42, and an interface unit 43, and further includes the storage unit 24 and the image recognition unit 25 described above. Note that the storage unit 24 and the image recognition unit 25 may be provided independently of the unit control unit 40.

  The main control unit 41 is configured by a CPU that controls the operation of each unit in the moving object detection unit 10. The information processing section 42 and the image recognizing section 25 may be constituted by the above-mentioned CPU (or may be integrated with the main control section 41), or may be another arithmetic section or a circuit for performing a specific process. It may be configured.

  The information processing unit 42 performs a predetermined algorithm on information (for example, image data) output from the optical detection unit 23 of the image recognition system 20 and information (for example, data on respiratory condition) output from the radio wave detection unit 30. Signal processing based on Information obtained by the signal processing is used for image recognition in the image recognition system 20 (particularly, the image recognition unit 25).

  A network cable (not shown) of the communication line 200 is electrically connected to the interface unit 43. Information on the state of the care receiver detected by the moving body detection unit 10 based on the image or the microwave is transmitted to the management server 100a via the interface unit 43 and the communication line 200.

[Supplement for radio wave detector]
Next, the description of the radio wave detection unit 30 will be supplemented. FIG. 6 is a cross-sectional view of the moving body detection unit 10 and the radio wave detection unit 30 in a state where the front cover 11a is attached to and detached from the main body 11b of the housing 11 to be described later. The radio wave detection unit 30 has a sensor unit 31 and a radome lens 32.

  The sensor unit 31 is a chip configured by a microwave Doppler sensor for individually detecting biological information of a cared person by emitting and receiving radio waves, and is mounted on a substrate 33. The sensor unit 31 includes an RF LSI (high frequency integrated circuit element), and a transmitting antenna and a receiving antenna for transmitting and receiving radio waves.

  The radome lens 32 is a radio wave lens for protecting the sensor unit 31 and controlling (for example, narrowing) the directivity of radio waves emitted from the sensor unit 31, and is provided in front of the sensor unit 31 (on the radio wave emission side). It is provided integrally with the sensor unit 31 via the holding unit 34 so as to be located. The radome lens 32 is formed of, for example, a plano-convex lens in which a surface 32a on the sensor unit 31 side is a flat surface and a surface 32b on the opposite side to the sensor unit 31 is convex on the radio wave radiation side. It is held by the holding portion 34 so as to pass through the center. Therefore, the direction of the sensor unit 31 matches the direction of the main axis of the radome lens 32.

  Here, the main axis of the radome lens 32 is an axis passing through the center of curvature of the surface 32b of the radome lens 32 and perpendicular to the surface 32a, and is synonymous with the optical axis or the rotationally symmetric axis. In addition, the angle defining the “direction of the sensor unit 31” is set such that the sensor unit 31 uses the direction perpendicular to the horizontal plane (here, the ceiling 101 a of the living room 101 in which the moving object detection unit 10 is installed) as the rotation axis. It is defined by the yaw angle when rotating, and the pitch angle when the sensor unit 31 rotates with the direction parallel to the horizontal plane as the rotation axis. However, in order to facilitate understanding of the description, unless otherwise specified, , Pitch angle.

  Further, here, when considering two rotation axes perpendicular to each other in a plane parallel to the horizontal plane, a pitch angle which is a rotation angle when rotating around one rotation axis (for example, the left-right direction) and the other, It is not necessary to distinguish between the rotation axis (for example, the front-back direction) and the yaw angle, which is the rotation angle when rotating about the rotation axis (for example, the one rotation axis becomes the other rotation axis by the rotation parallel to the horizontal plane). Therefore, both are treated as a pitch angle.

  The housing 11 of the above-described moving object detection unit 10 includes a front cover 11a located in front of the radome lens 32 (the side opposite to the sensor unit 31), and a remaining main body 11b. The front cover 11a is detachably mounted on the main body 11b. Accordingly, as described later, when the orientation of the sensor unit 31 is adjusted so as to face the bed 102 so that the sensor unit 31 detects the respiratory state of the care receiver while sleeping, the main unit 11b is moved forward. The adjustment can be performed by removing the cover 11a. When the adjustment of the direction of the sensor unit 31 is completed, the front cover 11a is attached to the main body 11b again.

  The substrate 33 on which the sensor unit 31 is mounted is fixed to a fixing member 38. The fixing member 38 is rotatably supported by a support 39 fixed to the main body 11b of the housing 11 so that the direction of the sensor unit 31 can be changed.

[Relationship between sensor direction and noise level]
Next, the relationship between the orientation of the sensor unit 31 and the noise level detected by the sensor unit 31 will be described.

(About noise level)
A signal (data) detected by the sensor unit 31 including the Doppler sensor is obtained as time-series (continuous) amplitude data. By performing a Fourier transform on these data, signal analysis in the frequency domain becomes possible. For example, when there is no cared person in the living room 101, the Fourier transform spectrum of the signal detected by the sensor unit 31 is obtained as a waveform as shown in FIG. Note that the power level on the vertical axis in FIG. 7 is indicated in an arbitrary unit (arbitary unit) corresponding to the intensity (dB) of the radio wave detected by the sensor unit 31 for convenience. The noise level indicates the spectrum shown in FIG. 7, that is, the magnitude (power level) of the signal detected by the sensor unit 31 when the care receiver to be detected is not in the living room 101.

  On the other hand, when the sensor unit 31 detects the respiratory state of the care receiver sleeping on the bed 102 in the living room 101, the Fourier transform spectrum of the detection signal has a waveform as shown in FIG. The spectrum is as if a respiratory signal was added. At this time, the ratio between the signal level at the respiratory frequency (about 0.2 Hz (near 12 times / minute)) and the noise level becomes the S / N (signal to noise) ratio. The detection accuracy of the respiratory condition is increased. When the S / N ratio is large, not only the respiratory frequency but also its harmonic components can be detected.

  Therefore, in order to detect a respiratory signal with a good S / N ratio, it is desirable that the noise level be as small as possible than the level of the detection signal (respiratory signal) of the care recipient's biological information. That is, in order to increase the detection accuracy of the sensor unit 31, it is necessary to reduce the noise level detected by the sensor unit 31 as much as possible.

  Here, as a result of various studies and analysis by the present inventors, it has been found that the main factor that deteriorates the noise level is a clutter signal. The clutter signal is a received wave that has not been Doppler shifted, that is, a received wave having the same frequency as a radiated radio wave (transmitted wave). Originally, a Doppler sensor is a sensor that detects a reflected wave that is reflected by a moving object and returns, but the transmitted wave is also a radio wave, so it is directly reflected by a stationary object that is not moving and received by the sensor. There are also reflected waves. The directly reflected wave is called a clutter signal.

  Normally, a clutter cancel circuit is built in the Doppler sensor, and has a function of canceling a clutter signal by electrical processing using a filter or the like. However, when a reflective object is present near the radio wave transmitting unit (transmitting antenna) of the sensor, a clutter signal that is higher than the ability to be canceled by the clutter cancel circuit is generated.

FIG. 9 schematically illustrates some generation paths of a clutter signal generated inside the moving object detection unit 10 illustrated in FIG. The generation path of the clutter signal is mainly the following three.
(1) Path A in which the radio wave transmitted from the transmitting antenna of the sensor unit 31 directly enters (leaks) into the receiving antenna.
(2) The radio wave transmitted from the transmission antenna of the sensor unit 31 is reflected by the surface 32a on the sensor unit 31 side of the radome lens 32, which is a stationary object located very close to the transmission antenna, and directly enters the sensor unit 31. Route B.
(3) Path C in which a radio wave transmitted from the transmitting antenna of the sensor unit 31 is reflected by the inner surface of the front cover 11a of the housing 11, which is a stationary object located near the transmitting antenna, and is directly incident on the sensor unit 31.

  Among the three paths A to C, the influence of the clutter signal generated on the path C has the largest influence on the noise as compared with the clutter signal generated on the other paths. This is suppressed to some extent by the design of the sensor unit 31 and the design of the radio wave detection unit 30 (including the setting of the positional relationship between the sensor unit 31 and the radome lens 32) with respect to the clutter signals generated in the paths A and B. However, regarding the clutter signal generated in the route C, the relative positional relationship between the sensor unit 31 and the front cover 11a is not fixed (the direction of the sensor unit 31 varies depending on the position of the bed 102 in the living room 101). Due to inability to control by design.

  Here, FIG. 10 schematically shows the relationship between the magnitude of the respiratory signal detected by the sensor unit 31 and the noise level. The upper figure shows the case where the noise level is relatively small, and the lower figure shows the noise level. The case where the level is relatively large is shown. In the figure, the “magnitude of the respiratory signal” on the horizontal axis represents the respiratory detection interval (for example, 0.1 to 0.1 including the respiratory frequency (around 0.2 Hz)) of the Fourier transform spectrum of the detection signal shown in FIG. A person with a small respiratory signal (for example, an elderly person) corresponds to the integral value (area) in the respiratory frequency band of 0.5 Hz, and the left side of the center of the horizontal axis (a person with a standard respiratory signal). And a person with a large respiratory signal (for example, a young person) is distributed on the right side with respect to the center of the horizontal axis. Further, “frequency” on the vertical axis corresponds to the total number (frequency) of persons showing the magnitude of a certain respiratory signal. Further, the noise level shown in FIG. 10 corresponds to the integral value of the signal detected by the sensor unit 31 in the unoccupied state in the breath detection section.

  As shown in the upper diagram of FIG. 10, if the noise level is sufficiently small with respect to the distribution of the magnitude of the respiratory signal, the respiratory signal can be detected even if the respiratory signal is small (the respiratory signal is not lost). . However, as shown in the lower diagram of FIG. 10, when the noise level is deteriorated (increased) by the clutter signal, the respiratory signal below the noise level is buried in the noise level, so that the respiratory signal cannot be detected (the respiratory signal is unreported). ). Therefore, in order to increase the detection accuracy of the respiratory signal, it is necessary to suppress an increase in the noise level due to the clutter signal.

  FIG. 11 shows a Fourier transform spectrum of a signal detected by the sensor unit 31 when the care receiver is not present in the living room 101, and shows a case where the clutter signal is large and a case where the clutter signal is small. The noise generated by the clutter signal is white noise generated at all frequencies. Therefore, when the clutter signal is large, the spectrum is such that the entire power level is offset upward as compared with the case where the clutter signal is small.

  FIG. 12 is a Fourier transform spectrum of the detection signal at the time of acquiring the respiratory signal of the care receiver, in which the clutter signal is higher than the power level of the respiratory signal to be detected. As shown in the figure, when the level of the respiratory signal to be detected is lower than the noise level raised by the clutter signal, the respiratory signal to be detected is buried in the noise, so that the respiratory signal cannot be detected.

  When the noise level is subtracted to cancel the clutter signal as in Patent Document 1 described above, if the power level of the respiratory signal to be detected is larger than the noise level as shown in FIG. Clutter signals can be canceled. However, as shown in FIG. 12, when the power level of the respiratory signal is lower than the noise level, the respiratory signal is buried in the noise, so that the respiratory signal cannot be detected even if the above-described subtraction processing is performed. In the care support system 1, since it is assumed that the subject includes an elderly person whose respiratory signal is never large and the clutter signal is also quite large, the clutter signal is canceled by a subtraction process as in Patent Literature 1. No method can be adopted. Therefore, it is necessary to reduce the clutter signal by a method other than the subtraction processing.

  By the way, the above-mentioned clutter signal is considered to be a composite wave of the transmitted wave and the reflected wave, similarly to the wave interference phenomenon. In the case of a wave, the composite wave becomes stronger or weaker depending on the position of the fixed end. In the case of the clutter signal, the fixed end corresponds to the radome lens 32 (surface 32a) and the front cover 11a of the housing 11 shown in FIG. Therefore, depending on the positional relationship between the radome lens 32 or the front cover 11a and the sensor unit 31 (particularly, the transmitting antenna), the clutter signal is also increased or decreased. That is, as shown in the upper diagram of FIG. 13, when the fixed end is located at a position where the reflected wave at the fixed end has an opposite phase to the transmission wave (incident wave), the transmission wave and the reflected wave cancel each other. (A synthesized wave (standing wave) having zero amplitude is obtained). On the other hand, as shown in the lower diagram of FIG. 13, when the fixed end is located at a position where the reflected wave at the fixed end has the same phase as the transmission wave, the transmission wave and the reflection wave reinforce each other (the amplitude of the transmission wave is (A composite wave (standing wave) that is twice as large as that of the above) is obtained.

  FIG. 14 schematically illustrates the direction of the sensor unit 31 that changes according to the positions of the plurality of beds 102 in the living room 101. In FIG. 14, the vertical direction perpendicular to the ceiling 101a (horizontal plane) is set as a reference (0 °), and the pitch angle θ of the sensor unit 31 from the vertical direction (here, the angle of the main axis of the radome lens 32 (the radome angle) )) Is changed from θ = 0 ° to θ = + 20 ° and θ = + 45 ° according to the position of the bed 102. In the care support system 1, the sensor unit 31 detects the respiratory state of the cared person P lying on the bed 102 while the cared person P is sleeping. The sensor unit 31 is operated in a direction of the bed 102.

  As shown in the figure, even if the direction of the sensor unit 31 is changed according to the position of the bed 102, the relative positional relationship (relative distance) between the sensor unit 31 (particularly, the transmitting antenna) and the radome lens 32 changes. However, the relative positional relationship (relative distance) between the sensor unit 31 and the front cover 11a changes. This depends on the position of the bed 102 installed in the living room 101 (by the distance between the moving body detection unit 10 and the bed 102 and the direction of the bed 102 viewed from the moving body detection unit 10), by the sensor unit 31 and the front cover 11a. It means that the relative distance to is changed.

  As described above, when the relative positional relationship between the sensor unit 31 and the front cover 11a changes depending on the orientation of the sensor unit 31, the position of the fixed end (the front cover 11a) shown in FIG. Changes. This means that the magnitude of the clutter signal (the amplitude and level of the composite wave) changes depending on the direction of the sensor unit 31, and the noise level detected by the sensor unit 31 changes according to the direction of the sensor unit 31.

  FIG. 15 shows an example of the relationship between the radome angle and the noise level. However, in the figure, the emission frequency (transmission wave frequency) of the radio wave from the sensor unit 31 is constant at A (Hz). The noise level on the vertical axis indicates an integrated value of a respiratory detection section in a Fourier transform spectrum of a signal detected by the sensor unit 31 when the user is unattended. Since the relative distance between the sensor unit 31 and the front cover 11a is different in each of the radome angles θ1 to θ4, it can be seen that the noise level changes according to the radome angle as shown in FIG. That is, the noise level has a radome angle dependency. With such characteristics, the detected noise level differs (variation) depending on the positional relationship between the moving object detection unit 10 and the bed 102 (the direction of the set sensor unit 31), and the fine body movement detection depends on the direction of the sensor unit 31. There will be differences in ability.

[How to reduce noise level]
In order to suppress the variation in the noise level due to the direction of the sensor unit 31, it is necessary to suppress the change in the noise level detected when the direction of the sensor unit 31 is changed. It may be considered that the position of the front cover 11a serving as the fixed end may be changed to a position where the noise level is reduced (a position where the clutter signal can be canceled) for each direction of the portion 31. However, in the moving body detection unit 10, it is practically difficult to change the above-described position of the front cover 11 a for each direction of the sensor unit 31 (nearly impossible). It is actually difficult to design the shape of the front cover 11a so that the noise level can be reduced without depending on it.

  Therefore, we will return to the nature of the waves and consider again. In the case of a wave, the magnitude of the composite wave can be reduced by changing the frequency (radiation frequency) of the transmission wave even if the position of the fixed end is the same. FIG. 16 schematically shows respective waveforms of the transmission wave, the reflected wave, and the composite wave when the emission frequency of the transmission wave is A (Hz), B (Hz), and C (Hz). Note that B = 1.1A and C = 0.9A. As shown in the figure, even if the position of the fixed end is the same, the magnitude (amplitude) of the composite wave changes by changing the radiation frequency of the transmission wave. For example, when the radiation frequencies are B and C, the amplitude of the composite wave is 30 to 40% smaller than that of the transmission wave (or the reflected wave) as compared with the case where the radiation frequency is A. This is because the phase of the transmission wave at the position of the fixed end is changed by changing the radiation frequency.

  As shown in FIG. 16, if the position of the fixed end is the same, when the emission frequency of the transmission wave changes, the magnitude of the synthetic wave, that is, the magnitude of the clutter signal also changes, so that the noise level depends on the radome angle. Also exhibit different characteristics depending on the radiation frequency. FIG. 17 shows the radome angle dependence of the noise level at different radiation frequencies A and B. In the figure, at the emission frequency A, the noise level increases as the radome angle increases, but at the emission frequency B, the noise level decreases as the radome angle increases. ing. As a result, when the radome angles are θ1 and θ2, the noise level is minimum when the radiation frequency is A, and when the radome angles are θ3 and θ4, the noise level is minimum when the radiation frequency is B.

  Therefore, a table defining the radiation frequency (specific radiation frequency) that minimizes the noise level for each radome angle is stored in the memory, and the specific radiation frequency corresponding to the set radome angle is obtained from the table. By radiating radio waves from the sensor unit 31 at such a specific radiation frequency, the noise level detected by the sensor unit 31 can be minimized at any radome angle, and the detection performance varies depending on the radome angle. Can be reduced. In the care support system 1 of the present embodiment, the emission frequency of the radio wave from the sensor unit 31 is controlled based on such a concept. Hereinafter, the characteristic configuration of the care support system 1 of the present embodiment will be described as specific examples 1 to 3.

[Specific example 1]
FIG. 18 is a block diagram illustrating a configuration of the care support system 1 according to the first embodiment. Although a part of the configuration of the image recognition unit 20 is omitted in FIG. 3 for convenience, the configuration of the image recognition unit 20 is as shown in FIG. In the care support system 1 of the specific example 1, the above-described radio wave detection unit 30 further includes a storage unit 35, a radiation control unit 36, and an interface unit 37, in addition to the above-described sensor unit 31, the radome lens 32, and the like. ing. The interface unit 37 is an interface for inputting and outputting information or control signals to and from the unit control unit 40, and includes an input / output port (terminal).

  The storage unit 35 can detect the biological information by detecting the noise level detected by the sensor unit 31 by the emission of the radio wave for each different direction (here, the radome angle) of the sensor unit 31 in the housing of the moving object detection unit 10. This is a memory that stores a table that defines a specific radiation frequency that is lower than a predetermined level (for example, that minimizes the noise level). The storage unit 35 includes, for example, a RAM, a ROM, a nonvolatile memory, and the like.

  FIG. 19 shows an example of a table stored in the storage unit 35. FIG. 20 shows an example of the specific radiation frequency obtained based on the radome angle dependence of the noise level shown in FIG. In FIG. 17, as described above, for the radome angles θ1 and θ2, the noise level is minimum at the radiation frequency A, and for the radome angles θ3 and θ4, the noise level is minimum at the radiation frequency B. It has become. Therefore, in the specific example 1, as shown in FIGS. 19 and 20, the radiation frequency A is set as the specific radiation frequency for the radome angles θ1 and θ2, and the radiation frequency B is set for the radome angles θ3 and θ4. Set as frequency. The storage unit 35 stores a table (radiation frequency setting table) indicating the correspondence between the radome angle and the specific radiation frequency.

  The radiation control unit 36 is a control unit that controls the radiation frequency of radio waves in the sensor unit 31, and is configured by, for example, a CPU. In particular, the radiation control unit 36 obtains the radiation frequency of the radio wave radiated from the sensor unit 31 based on the table stored in the storage unit 35 according to the setting of the direction of the sensor unit 31. Switching to a specific radiation frequency corresponding to the direction (radome angle).

  For example, when the radome angle is changed from θ2 to θ3 with a change in the position of the bed 102 in the living room 101, the radiation control unit 36 refers to the table and refers to the specific radiation frequency corresponding to the radome angle θ3 ( The radiation frequency B) is grasped, and the radiation frequency is switched from the specific radiation frequency (radiation frequency A) corresponding to the radome angle θ2 to the specific radiation frequency (radiation frequency B) corresponding to the radome angle θ3. Thereby, the sensor unit 31 emits a radio wave at the emission frequency B after the switching.

  Here, the radiation control unit 36 can determine whether the radome angle has been changed by using image recognition of a captured image. That is, in the configuration in which the moving object detection unit 10 includes the optical detection unit 23 and the image recognition unit 25, the image detection by the image recognition unit 25 (the shape of the bed 102) By recognizing, the shape and position of the bed 102 are recognized, whereby the sleeping place of the care receiver can be specified in the image. When the sleeping place can be specified in the image, the angle of view corresponding to the sleeping place, that is, the vertical and horizontal angles of view of the sleeping place (the position of the bed 102) in the image can be known. The sensor unit 31 is installed on the ceiling 101a of the living room 101 as the moving object detection unit 10 together with the optical detection unit 23, and the direction of the sensor unit 31 is directed toward the bed 102, so that the sensor unit 31 corresponds to the sleeping place in the image. The angle of view may be considered to indicate the direction of the bed 102 viewed from the moving object detection unit 10, that is, the direction of the sensor unit 31. Therefore, the radiation control unit 36 can determine whether or not the direction of the sensor unit 31 has been changed (change of the radome angle) by using image recognition of the captured image.

  As described above, according to the setting of the direction of the sensor unit 31, the radiation frequency of the radio wave radiated from the sensor unit 31 is changed by the radiation control unit 36 based on the table to the specific radiation corresponding to the direction of the sensor unit 31. Switching to frequency. Thus, no matter what direction the sensor unit 31 is set by changing the position of the bed 102 in the living room 101, the noise level detected by the sensor unit 31 is minimized. Therefore, even when the signal of the biological information to be detected (respiration signal) is small, the signal can be reliably detected in a state where noise including clutter has been reduced from the beginning. Therefore, the noise can be reduced without performing post-processing for subtracting the clutter signal as in the related art, and the detection accuracy of the sensor unit 31 can be improved. In addition, since the detected noise level is minimized in any direction of the sensor unit 31, it is possible to suppress a variation in detection performance depending on the direction of the sensor unit 31.

  In addition to the paths A to C shown in FIG. 9, the clutter signal that is a main factor of the noise level includes radio waves directly incident on the sensor unit 31 through other paths (for example, radio waves satisfying resonance conditions). It is. However, in the specific example 1, the specific radiation frequency at which the overall noise level is minimized, including the noise due to such a direct incident wave, is set. The generated clutter signals can be collectively reduced to reduce the overall noise, whereby the detection accuracy of the sensor unit 31 can be reliably increased.

  In addition, since the moving object detection unit 10 includes the storage unit 35 and the radiation control unit 36 described above, the moving object detection unit 10 alone (independent of an instruction from the management server 100a) performs internal processing of the moving object detection unit 10. Accordingly, it is possible to switch to the specific radiation frequency according to the setting of the direction of the sensor unit 31.

  In particular, in a configuration in which the moving object detection unit 10 includes the optical detection unit 23 and the image recognition unit 25, the radiation control unit 36 performs the operation based on the angle of view corresponding to the sleeping place (the position of the bed 102) in the captured image. The direction of the sensor unit 31 can be grasped. Thereby, the radiation control unit 36 can automatically switch the radiation frequency of the radio wave radiated from the sensor unit 31 to the specific radiation frequency corresponding to the direction of the sensor unit 31 with reference to the table. In other words, the change in the direction of the sensor unit 31 or the setting thereof can be used as a trigger to allow the moving object detection unit 10 (the radio wave detection unit 30) itself to switch the emission frequency of the sensor unit 31 to the specific emission frequency.

  Further, since the radome lens 32 of the radio wave detection unit 30 is provided integrally via the sensor unit 31 and the holding unit 34, depending on the position of the bed 102, the orientation of the sensor unit 31 together with the radome lens 32 depends on the position. Even if it changes as described above, while the radio wave directivity is appropriately controlled by the radome lens 32, the detection accuracy in the sensor unit 31 can be increased by switching to the specific radiation frequency, and the orientation of the sensor unit 31 can be improved. This can reduce the variation in detection performance due to this.

  Further, the table stored in the storage unit 35 defines a specific radiation frequency that minimizes the noise level for each different direction (the radome angle) of the sensor unit 31 in the housing 11 (FIG. 19). The radiation control unit 36 switches the radiation frequency to the specific radiation frequency corresponding to the direction of the sensor unit 31 with reference to the table, thereby minimizing the noise level detected by the sensor unit 31 by radio wave radiation. . As a result, a signal (for example, a respiratory signal) to be detected by the sensor unit 31 can be reliably obtained.

  Note that the specific radiation frequency stored in the table is not limited to the radiation frequency at which the noise level is minimized. The specific radiation frequency may be any radiation frequency at which the noise level detected by the sensor unit 31 is lower than a predetermined level at which biological information can be detected.

  For example, FIG. 21 shows another example of the specific radiation frequency set for each radome angle. As shown in the figure, at the radome angles θ1 and θ2, even if the radiation frequency P (Hz) is between the radiation frequency A and the radiation frequency B, the noise level (Fourier If the integrated value of the respiration detection section in the converted spectrum) is smaller than a predetermined level Nth at which biological information can be detected, such a radiation frequency P may be set as the specific radiation frequency. Similarly, at the radome angles θ3 and θ4, even if the radiation frequency Q (Hz) is between the radiation frequency A and the radiation frequency B, the noise level detected by the sensor unit 31 is lower than the predetermined level Nth. If it becomes smaller, such a radiation frequency Q may be set as the specific radiation frequency.

  At the radiation frequency P, the noise level increases at the radome angles θ1 and θ2 compared to the radiation frequency A, and at the radiation frequency Q, the noise level increases at the radome angles θ3 and θ4 compared to the radiation frequency B. However, each of these noise levels is lower than the predetermined level Nth at which the biological information can be detected and lower than the level of the respiratory signal to be detected, so that the noise level is lower than the level of the respiratory signal as shown in FIG. The detection accuracy of the respiratory signal can be improved as compared with the case where the respiratory signal is largely buried in the noise level.

  In the above description, the bed 102 in the living room 101 is assumed as the sleeping place of the cared person. However, for the cared person who sleeps on a futon on the floor without setting the bed 102 in the living room 101, The above futon can be considered as a sleeping place. Even in this case, since the bed position can be specified by recognizing the shape and position of the futon by image recognition, the radiation control unit 36 grasps the orientation of the sensor unit 31 based on the angle of view corresponding to the bed position in the image. can do.

  The storage unit 35 and the radiation control unit 36 of the radio wave detection unit 30 may be provided in the unit control unit 40, and the storage unit 24 and the main control unit 41 of the unit control unit 40 The function of the radiation control unit 35 and the radiation control unit 36 may be performed.

[Specific example 2]
FIG. 22 is a block diagram illustrating a configuration of the care support system 1 of the specific example 2. In the specific example 2, the table described in the specific example 1 is stored in the management server 100a of the care support system 1, and the management server 100a sends a request to the moving object detection unit 10 to switch to the specific radiation frequency grasped from the table. Then, based on the switching request, the radiation frequency of the sensor unit 31 is switched. More specifically, it is as follows.

  The radio wave detection unit 30 of the care support system 1 has the same configuration as that of the specific example 1 except that the storage unit 35 is omitted from the radio wave detection unit 30 of the specific example 1 shown in FIG. 32 (see FIG. 6 and the like), a radiation control unit 36 and an interface unit 37 are provided. The emission control unit 36 controls the emission of radio waves in the sensor unit 31, but differs from the first embodiment in that the emission control unit 36 controls the emission of radio waves based on a control signal from a management control unit 111 described later of the management server 100 a. ing.

  The management server 100a has a management control unit 111, a storage unit 112, an input unit 113, and an interface unit 114. The interface unit 114 is an interface for inputting and outputting information or control signals to and from the unit control unit 40 via the communication line 200, and includes an input / output port (terminal).

  The management control unit 111 is configured by a CPU that controls the operation of each unit of the management server 100a. The storage unit 112 is a memory that stores the table shown in FIG. 19 that indicates the correspondence between the radome angle and the specific radiation frequency, and is configured by, for example, a hard disk. The input unit 113 includes, for example, a keyboard, a mouse, a touch panel, and the like, and is provided for inputting information regarding the direction of the sensor unit 31.

  Further, a user (administrator) of the system owns (ports) the external terminal 300 that can wirelessly communicate with the management server 100a via the communication line 200. Thereby, the user can provide various information to the management server 100a via the external terminal 300. As the external terminal 300, for example, a terminal having at least an input unit, such as a multifunctional mobile terminal such as a tablet or a smartphone, or a notebook personal computer can be assumed.

  In the above system configuration, when the radome angle is changed in accordance with the change of the position of the bed 102 in the living room 101, the user of the system inputs the changed radome angle by the input unit 113 of the management server 100a. The external terminal 300 inputs the changed radome angle and transmits the information to the management server 100a. Then, the management control unit 111 refers to the table stored in the storage unit 112, obtains a specific radiation frequency corresponding to the input radome angle, and issues a control signal (setting command to request switching to the specific radiation frequency obtained). ) Is transmitted to the moving object detection unit 10. The moving object detection unit 10 receives the control signal, and the emission control unit 36 switches the emission frequency of the radio wave emitted from the sensor unit 31 to the specific emission frequency based on the control signal. Thereby, the sensor unit 31 emits a radio wave at the specific radiation frequency after the switching.

  In the care support system 1 of the specific example 2, since the management server 100a has the storage unit 112 storing the table, it is not necessary to provide a large-capacity memory in the moving body detection unit 10, and The manufacturing cost can be reduced and the size can be reduced. In addition, the management control unit 111 transmits a control signal requesting switching to the specific radiation frequency obtained based on the table to the moving object detection unit 10, and upon receiving the control signal, the radiation control unit 36 of the moving object detection unit 10 Then, the radiation frequency of the sensor unit 31 is switched to the specific radiation frequency. Therefore, in the configuration in which the management server 100 manages the radiation frequency of the sensor unit 31, the detection accuracy in the sensor unit 31 can be increased, and the variation in the detection performance due to the orientation of the sensor unit 31 can be reduced. The effect of can be obtained.

  Further, when information on the orientation of the sensor unit 31 is input by the input unit 113 or when the information is received from the external terminal 300, the management control unit 111 A specific radiation frequency corresponding to the direction of the unit 31 is obtained, and a control signal requesting switching to the specific radiation frequency is transmitted to the moving object detection unit 10. The management control unit 111 can grasp the direction of the sensor unit 31 based on the information input from the input unit 113 or the information received from the external terminal 300, and thereby can determine the specific radiation frequency corresponding to the direction of the sensor unit 31. It can be determined based on the table. Therefore, the management control unit 111 can request the moving object detection unit 10 to switch to an appropriate specific radiation frequency (transmission of a control signal).

  By the way, in the configuration in which the moving body detection unit 10 includes the above-described optical detection unit 23 (see FIG. 3) and the image recognition unit 25, the angle of view indicating the sleeping place in the image and the angle of view based on the angle of view, as shown in the specific example 1. The orientation of the sensor unit 31 may be grasped by the management server 100a. That is, the information acquired by the optical detecting unit 23 and the image recognizing unit 25 (information of the photographed image and the sleeping place specified in the image) is transmitted to the management server 100a, and the management control unit 111 performs the processing based on the information. Alternatively, the angle of view and the direction of the sensor unit 31 corresponding to the sleeping place in the image may be grasped. Then, the management control unit 111 obtains a specific radiation frequency corresponding to the direction of the sensor unit 31 based on the table stored in the storage unit 112, and outputs a control signal requesting switching to the specific radiation frequency to the moving object detection unit. 10 may be sent.

  In this case, the management server 100a (management control unit 111) can detect the sensor based on the information output from the moving object detection unit 10 even if no information regarding the direction of the sensor unit 31 is input from the input unit 113 or the external terminal 300. The direction of the unit 31 can be grasped, and the specific radiation frequency corresponding to the direction of the sensor unit 31 can be obtained based on the table. As a result, the management control unit 111 can request the moving object detection unit 10 to switch to an appropriate specific radiation frequency (transmission of a control signal).

[Specific example 3]
The care support system 1 of the specific example 1 or 2 is different from the care support system 1 of the specific example 1 or 2 except that the table stored in the storage unit (the storage unit 35 of the radio wave detection unit 30 or the storage unit 112 of the management server 100a) is different. Is the same as FIG. 23 illustrates an example of a table stored in the storage unit of the care support system 1 according to the third embodiment. In the specific examples 1 and 2, the angle defining the direction of the sensor unit 31 is only the radome angle, but strictly, it is necessary to consider the radome rotation angle. The radome rotation angle corresponds to a yaw angle when the sensor unit 31 rotates around a direction perpendicular to a horizontal plane (the ceiling 101a) as a rotation axis. Note that the radome angle described above corresponds to a pitch angle when the sensor unit 31 rotates around a direction parallel to the horizontal plane as a rotation axis. When the radome rotation angle changes, the relative positional relationship (relative distance) between the sensor unit 31 and the front cover 11a changes depending on the shape of the front cover 11a of the housing 11, and as a result, according to the radome rotation angle. , The noise level changes.

  Therefore, in Example 3, both the radome rotation angle and the radome angle are considered as the angle that defines the direction of the sensor unit 31, and noise is generated for each direction of the sensor unit 31 defined by both the radome rotation angle and the radome angle. The specific radiation frequency at which the level is minimized is set in advance, and the correspondence is stored as a table in the storage unit (the storage unit 35 or the storage unit 112). The specific emission frequency corresponding to the set direction of the sensor unit 31 is determined from the table, and the sensor unit 31 is driven (switches the emission frequency) at the determined specific emission frequency, as in the first or second embodiment.

  As in Example 3, the direction of the sensor unit 31 is three-dimensionally defined using the yaw angle and the pitch angle, and the relationship between the direction of the sensor unit 31 and the specific radiation frequency is stored as a table. Regardless of the direction of the interior 31 in the living room 101, which is a three-dimensional space, switching to an appropriate specific radiation frequency in accordance with the orientation of the sensor unit 31 is realized, and the detection accuracy of the sensor unit 31 is improved. In addition, it is possible to reduce variation in detection performance due to the direction of the sensor unit 31.

  Although the configuration in which the radio wave detection unit 30 includes the radome lens 32 has been described above, the radome lens 32 may be provided as necessary, and the installation of the radome lens 32 may be omitted. In the radio wave detection unit 30, when the radome lens 32 is not provided, the direction of the sensor unit 31 may be considered to be a direction perpendicular to the substrate 33 on which the sensor unit 31 is mounted. In addition, the above-mentioned “radome angle” may be read as “pitch angle of the sensor unit 31”, and “radome rotation angle” may be read as “yaw angle of the sensor unit 31”.

  In the above description, the orientation of the sensor unit 31 after the change is grasped by image recognition (see specific example 1) or manual input (see specific example 2), but after the change using the pitch angle sensor or the like. Alternatively, the specific radiation frequency corresponding to the direction of the sensor unit 31 may be obtained based on a table by reading the direction (angle) of the sensor unit 31.

  Although the embodiments of the present invention have been described above, the scope of the present invention is not limited thereto, and can be implemented with various modifications without departing from the gist of the invention. For example, it is of course possible to configure the care support system 1 including both the configurations of the specific examples 1 and 2.

[Others]
The care support system according to the present embodiment described above can be expressed as follows, and the following effects can be obtained.

  The care support system described in the present embodiment is disposed in the housing of the moving object detection unit installed in the living room of the subject, and a sensor unit that detects biological information of the subject by emitting and receiving radio waves, A radiation control unit that controls a radiation frequency of a radio wave, and for each different direction of the sensor unit in the housing, a noise level detected by the sensor unit is smaller than a predetermined level at which the biological information can be detected. A storage unit that stores a table that defines a specific radiation frequency such that, the radiation control unit, according to the setting of the orientation of the sensor unit, the radiation frequency of the radio wave emitted from the sensor unit, Switching to the specific radiation frequency corresponding to the direction of the sensor unit, which is obtained based on the table.

  According to the above configuration, the radiation control unit switches the radiation frequency of the radio wave radiated from the sensor unit to the specific radiation frequency obtained based on the table according to the setting of the direction of the sensor unit. Thus, regardless of the orientation of the sensor unit, the noise level detected by the sensor unit is lower than a predetermined level at which biological information can be detected, and noise (including clutter) is reduced from the beginning. A signal (detection signal of biological information) is obtained. Therefore, the noise can be reduced without performing post-processing of subtracting the clutter signal from the detection signal as in the related art, and the detection accuracy in the sensor unit can be improved. In addition, no matter what direction the sensor unit is set, the noise level is low, so that it is possible to suppress variations in detection performance depending on the direction of the sensor unit.

  The moving object detection unit may include the radiation control unit and the storage unit. In this case, the switching to the specific radiation frequency corresponding to the direction of the sensor unit can be performed by the internal processing of the moving object detection unit (independently of the moving object detection unit) even if there is no instruction from the outside (for example, the management server). Can be.

  The moving body detection unit identifies an sleeping area by recognizing a position of a bed or a futon in the living room by image recognition from an image capturing unit that captures an image of the living room to obtain an image and an image obtained by the imaging unit. The radiation control unit further includes: an image recognition unit configured to determine an orientation of the sensor unit based on an angle of view corresponding to the sleeping place in the image acquired by the imaging unit. The radiation frequency of the radio wave radiated from the unit may be switched to the specific radiation frequency corresponding to the direction of the sensor unit, which is obtained based on the table.

  In the configuration in which the moving body detection unit includes the imaging unit and the image recognition unit, the position (sleeping place) of a bed or the like can be specified by image recognition from an image obtained by photographing the living room, and thereby, the sleeping in the image can be performed. The vertical (horizontal) and horizontal (photographing) view angles of the place can be understood. The sensor unit is provided in the moving object detection unit together with the imaging unit, and is usually installed in the unit in the direction of the sleeping place for the purpose of detecting a respiratory state or the like of the subject while the subject is sleeping. May be considered to indicate the direction of the sensor unit. Therefore, the radiation control unit grasps the direction of the sensor unit from the angle of view whenever the direction of the sensor unit is set (adjusted), even if no information regarding the direction of the sensor unit is input from outside. It is possible to automatically switch to a specific radiation frequency corresponding to the direction.

  The system further includes a management server that manages information output from the motion detection unit, the motion detection unit includes the radiation control unit, and the management server is stored in the storage unit and the storage unit. And a management control unit that transmits a control signal requesting switching to the specific radiation frequency obtained based on the table to the moving body detection unit, wherein the radiation control unit of the moving body detection unit performs the management control. The radiation frequency of the radio wave radiated from the sensor unit may be switched to the specific radiation frequency based on the control signal transmitted from the unit.

  Since the management server has the storage unit that stores the table, it is not necessary to provide a large-capacity memory in the moving object detection unit, and the manufacturing cost and the size of the moving object detection unit can be reduced. In addition, the management control unit of the management server transmits a control signal requesting switching to a specific radiation frequency obtained based on the table to the moving body detection unit, and the radiation control unit of the moving body detection unit is based on the control signal. Then, the radiation frequency of the sensor unit is switched to the specific radiation frequency. Therefore, in a configuration in which the management server (particularly, the management control unit) manages the radiation frequency of the sensor unit, the above-described effects can be obtained such that the detection accuracy in the sensor unit can be improved without performing the subtraction process.

  The management server includes an input unit for inputting information on the orientation of the sensor unit, and the management control unit, when the information is input by the input unit, based on the table, the sensor unit May be obtained, and the control signal may be transmitted to the moving object detection unit. The management control unit can grasp the direction of the sensor unit from the information input by the input unit, and can obtain the specific radiation frequency corresponding to the direction of the sensor unit based on the table. As a result, the management control unit can request the moving object detection unit to switch to an appropriate specific radiation frequency (transmit a control signal).

  The management control unit, when receiving information on the orientation of the sensor unit from an external terminal capable of communicating with the management server, determines the specific radiation frequency corresponding to the orientation of the sensor unit based on the table. The control signal may be transmitted to the moving object detection unit. In this case, the management control unit may grasp the direction of the sensor unit from information received from an external terminal (for example, a multifunctional portable terminal), and determine the specific radiation frequency corresponding to the direction of the sensor unit based on the table. it can. As a result, the management control unit can request the moving object detection unit to switch to an appropriate specific radiation frequency (transmit a control signal).

  The moving body detection unit identifies an sleeping area by recognizing a position of a bed or a futon in the living room by image recognition from an image capturing unit that captures an image of the living room to obtain an image and an image obtained by the imaging unit. Further comprising an image recognition unit that performs, the management control unit outputs from the moving body detection unit, based on the information of the image and the sleeping place, the angle of view corresponding to the sleeping place in the image and The direction of the sensor unit may be grasped, the specific radiation frequency corresponding to the direction of the sensor unit may be obtained based on the table, and the control signal may be transmitted to the moving object detection unit.

  In the configuration in which the moving body detection unit includes the imaging unit and the image recognition unit, the position (sleeping place) of a bed or the like can be specified by image recognition from an image obtained by photographing the living room, and thereby, the sleeping in the image can be performed. The vertical (horizontal) and horizontal (photographing) view angles of the place can be understood. The sensor unit is provided in the moving body detection unit together with the imaging unit, and is usually installed in the unit in the direction of the sleeping place for the purpose of detecting a respiratory state or the like of the subject while sleeping. May be considered to indicate the direction of the sensor unit. Therefore, the management server (management control unit) can control the information based on the information output from the moving object detection unit (the captured image and the information on the sleeping place) even if no information regarding the direction of the sensor unit is input from the input unit or the external terminal. Thus, the angle of view and the direction of the sensor unit can be grasped, and the specific radiation frequency corresponding to the direction of the sensor unit can be obtained based on the table. As a result, the management control unit can request the moving object detection unit to switch to an appropriate specific radiation frequency (transmit a control signal).

  The angle defining the direction of the sensor unit is a yaw angle when the sensor unit rotates with a direction perpendicular to a horizontal plane as a rotation axis, and a yaw angle when the sensor unit rotates with a direction parallel to the horizontal plane as a rotation axis. It may include a pitch angle. In this case, since the direction of the sensor unit is three-dimensionally defined using the yaw angle and the pitch angle, the direction of the sensor unit can be determined regardless of the direction of the sensor unit in a living room that is a three-dimensional space. By switching to the corresponding specific radiation frequency, it is possible to obtain the above-described effects such as the detection accuracy of the sensor unit can be increased without performing the subtraction processing.

  The system may further include a radome lens provided integrally with the sensor unit via a holding unit and controlling the directivity of the radio wave radiated from the sensor unit. In this case, no matter how the direction of the sensor unit changes together with the radome lens, the directivity of the radio wave is appropriately controlled by the radome lens, and the subtraction process is performed by switching to the specific radiation frequency corresponding to the direction of the sensor unit. The above-mentioned effects such as that the detection accuracy in the sensor unit can be improved without performing the above-described operations can be obtained.

  The table may define the specific radiation frequency that minimizes the noise level for each of different directions of the sensor unit in the housing. By switching to the specific radiation frequency corresponding to the direction of the sensor unit, the noise level detected by the sensor unit by the emission of radio waves is minimized, so that the signal to be detected by the sensor unit (the detection signal of the biological information to be observed) ) Can be reliably obtained.

  INDUSTRIAL APPLICABILITY The present invention can be used for a care support system that supports the daily life of a subject such as a care recipient in a living room.

DESCRIPTION OF SYMBOLS 1 Care support system 10 Moving body detection unit 11 Housing 11a Front cover 23 Optical detection unit (imaging unit)
25 image recognition unit 31 sensor unit 32 radome lens 34 holding unit 35 storage unit 36 radiation control unit 100a management server 101 living room 102 bed 111 management control unit 112 storage unit 113 input unit 300 external terminal

Claims (10)

A sensor unit that is arranged in the housing of the moving object detection unit installed in the living room of the subject and detects biological information of the subject by emitting and receiving radio waves,
A radiation control unit that controls a radiation frequency of the radio wave,
For each different orientation of the sensor unit in the housing, a table that defines a specific radiation frequency such that a noise level detected by the sensor unit is smaller than a predetermined level at which the biological information can be detected is stored. And a storage unit for
The radiation control unit obtains, based on the table, a radiation frequency of the radio wave radiated from the sensor unit according to the setting of the direction of the sensor unit, the specific radiation corresponding to the direction of the sensor unit. Switching to a frequency, care support system.   The care support system according to claim 1, wherein the moving body detection unit includes the radiation control unit and the storage unit. The moving body detection unit,
An imaging unit that captures an image by photographing a living room;
From the image acquired by the imaging unit, further comprising an image recognition unit that recognizes the position of a bed or futon in the living room by image recognition and specifies a sleeping place,
The radiation control unit grasps the direction of the sensor unit based on an angle of view corresponding to the sleeping place in the image acquired by the imaging unit, and radiates the radio wave radiated from the sensor unit. The care support system according to claim 2, wherein a frequency is switched to the specific radiation frequency corresponding to the direction of the sensor unit, which is obtained based on the table. The system further includes a management server that manages information output from the motion detection unit,
The moving body detection unit includes the radiation control unit,
The management server is
The storage unit;
A management control unit that transmits to the moving object detection unit a control signal requesting switching to the specific radiation frequency obtained based on the table stored in the storage unit,
The radiation control unit of the moving object detection unit switches a radiation frequency of the radio wave radiated from the sensor unit to the specific radiation frequency based on the control signal transmitted from the management control unit. The care support system described in. The management server includes an input unit for inputting information on an orientation of the sensor unit,
When the information is input by the input unit, the management control unit obtains the specific radiation frequency corresponding to the direction of the sensor unit based on the table, and transmits the control signal to the moving object detection unit The care support system according to claim 4, wherein   The management control unit, when receiving information on the orientation of the sensor unit from an external terminal capable of communicating with the management server, determines the specific radiation frequency corresponding to the orientation of the sensor unit based on the table. The care support system according to claim 4, wherein the control signal is transmitted to the moving body detection unit. The moving body detection unit,
An imaging unit that captures an image by photographing a living room;
From the image acquired by the imaging unit, further comprising an image recognition unit that recognizes the position of a bed or futon in the living room by image recognition and specifies a sleeping place,
The management control unit is output from the moving body detection unit, based on the information of the image and the sleeping place, based on the angle of view corresponding to the sleeping place in the image and the orientation of the sensor unit, The care support system according to claim 4, wherein the specific radiation frequency corresponding to the direction of the sensor unit is obtained based on the table, and the control signal is transmitted to the moving body detection unit.   The angle defining the direction of the sensor unit is a yaw angle when the sensor unit rotates with a direction perpendicular to a horizontal plane as a rotation axis, and a yaw angle when the sensor unit rotates with a direction parallel to the horizontal plane as a rotation axis. The care support system according to any one of claims 1 to 7, comprising a pitch angle.   9. The care support system according to claim 1, further comprising a radome lens that is provided integrally with the sensor unit and the holding unit and controls a directivity of the radio wave emitted from the sensor unit. 10. .   The care support according to any one of claims 1 to 9, wherein the table defines the specific radiation frequency such that the noise level is minimized for each of different directions of the sensor unit in the housing. system.

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