WO2018216362A1 - Care support system - Google Patents

Abstract

This care support system includes a sensor unit, an emission control unit, and a storage unit. The sensor unit is disposed in a housing of a moving body detection unit installed in a room of a subject, and detects biological information related to the subject by emitting and receiving radio waves. The storage unit stores a table specifying, for each of a plurality of different orientations of the sensor unit in the housing, a specific emission frequency at which a noise level detected by the sensor unit is smaller than a prescribed level at which the biological information can be detected. The emission control unit switches the emission frequency of the radio waves emitted from the sensor unit to the specific emission frequency which corresponds to the orientation of the sensor unit, and which is obtained on the basis of the table, in accordance with the setting of the orientation of the sensor unit.

Description

Care support system

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

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

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

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

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

Also, in nursing care facilities, there are many cared people who spend most of their day in the room due to reasons such as aging and physical disabilities. For this reason, in the care support system constructed in the care facility, it is not possible to freely create a situation in which no care recipient exists in the room and only the clutter exists. For this reason, in the use of the care support system, it is difficult to use the method of Patent Document 1 that intentionally creates a situation where only clutter exists and performs the subtraction process.

In the care support system, the sensor unit (Doppler sensor) is covered with a casing, and is installed on the ceiling of a living room, for example. And the direction of a sensor part is normally adjusted so that it may face the direction of the bed and the futon in a living room (in order to detect the respiratory state in bedtime). When the orientation of the sensor unit is adjusted, the relative positional relationship (for example, the 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 constant, the sensor Depending on the orientation of the part, unnecessary reflected waves (clutter) radiated from the sensor part and reflected by the inner surface of the housing and returning to the sensor part increase, and the detection performance varies depending on the orientation of the sensor part. Therefore, it is desired to suppress an increase in noise caused by a change in the relative position with respect to the housing, and to suppress a variation in detection performance due to the orientation of the sensor unit, regardless of the orientation of the sensor unit.

The present invention has been made in order to solve the above-described problems. The object of the present invention is to reduce detection accuracy in a sensor unit (Doppler sensor) by reducing clutter as noise without performing subtraction processing of the clutter signal. An object of the present invention is to provide a care support system that can suppress variation in detection performance due to the orientation of a sensor unit.

A care support system according to one aspect of the present invention is disposed in a casing of a moving object detection unit installed in a subject's room, and detects a biological information of the subject by emitting and receiving radio waves, The noise level detected by the sensor unit for each different direction of the radiation control unit that controls the radiation frequency of the radio wave and the sensor unit in the housing 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 that decreases, and 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. The specific radiation frequency corresponding to the direction of the sensor unit obtained based on the table is switched.

In the care support system, the clutter signal subtraction process is not performed in post-processing, and noise clutter can be reduced to increase detection accuracy at the sensor unit, and variations in detection performance due to the orientation of the sensor unit can be suppressed. .

It is explanatory drawing which shows the structure of the outline of the care support system which concerns on one Embodiment of this invention. It is explanatory drawing which shows typically the mode 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 mode of the living room in which the 2nd electromagnetic wave detection part was installed. It is a block diagram which shows the schematic structure of the said moving body detection unit. It is a block diagram which shows the detailed structure of the optical detection part which the said moving body detection unit has. It is explanatory drawing which shows typically an example of the image acquired by imaging | photography with the said optical detection part. It is sectional drawing of the said moving body detection unit and an electromagnetic wave detection part in each of the attachment state of the front cover of the housing | casing of the said moving body detection unit, and a detached state. It is explanatory drawing which shows an example of the Fourier-transform spectrum of the detection signal when it is unmanned output from the said electromagnetic wave detection part. It is explanatory drawing which shows the Fourier-transform spectrum of a detection signal when the care receiver's respiratory state is detected. It is explanatory drawing which shows typically the generation path | route of the clutter signal which generate | occur | produces inside the moving body detection unit shown in FIG. It is explanatory drawing which shows typically the relationship between the magnitude | size of the respiration signal detected by the sensor part of the said electromagnetic wave detection part, and a noise level. It is explanatory drawing which shows the magnitude | size of a clutter signal for the Fourier-transform spectrum of the signal detected by the said sensor part at the time of unattended. It is explanatory drawing which shows the Fourier-transform spectrum of the detection signal in the said sensor part in case a clutter signal is larger than the power level of a respiration signal. It is explanatory drawing for demonstrating the interference phenomenon of a wave. It is explanatory drawing which shows direction of the said sensor part which changes according to the position of the some bed in a living room. It is explanatory drawing which shows an example of the relationship between a radome angle and a noise level. It is explanatory drawing which shows typically each waveform of a transmission wave, a reflected wave, and a synthetic wave at the time of changing the radiation frequency of a transmission wave. It is explanatory drawing which shows the radome angle dependence of the noise level in a different radiation frequency. It is a block diagram which shows the structure of the care support system of the 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. It is explanatory drawing which shows an example of the specific radiation frequency obtained based on the radome angle dependence of the noise level shown in FIG. 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 specific example 2. In the care support system of the specific example 3, it is explanatory drawing which shows an example of the table memorize | stored in a memory | storage part.

An 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 living in a nursing facility or a general house, or a patient admitted to a hospital (nurse), and is also called a monitoring system. It is. The cared person and the cared person are objects to be supported by the care support system 1, that is, a target person (subject) managed by recognition or detection in the image recognition system 20 or the radio wave detection unit 30 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 stuffing station for caregivers who support the lives of the care recipients who spend at the care facilities. The staff station 100 is provided with a management server 100a and a display unit 100b. The management server 100a is a terminal device that is communicably connected to a later-described moving object detection unit 10 installed in the living room 101 via the communication line 200, and includes a central processing unit (CPU; Central Processing Unit). Composed. The communication line 200 is configured by, 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 transmitted (output) from the moving body detection unit 10 (for example, a captured image in the living room 101 and biological information of the care recipient) via the communication line 200, The received information is displayed on the display unit 100b. Thereby, the caregiver of the care facility can grasp the state in the living room 101 and the biological information of the care recipient by looking at the information displayed on the display unit 100b. The display unit 100b can be configured by a display of a personal computer, for example. In addition, when it is recognized that an operation of the cared person is abnormal, such as when the cared person falls on the floor by an image recognition process in the image recognition system 20 described later, the management server 100a moves the moving object detection unit. 10 is transmitted to the mobile terminal owned by the caregiver and the data of the captured image in the living room 101 acquired by the optical detection unit 23 of the moving object detection unit 10 is received. It is also possible to inform the caregiver. Note that, when 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 care facility, 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 a care recipient is installed. In addition, when two or more care recipients move in one living room 101, a plurality of beds 102 corresponding to each of the care recipients are installed.

FIG. 2 is an explanatory diagram schematically showing the inside of 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 the ceiling portion 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 in which a plurality of beds 102 are installed, the moving object detection unit 10 is installed on the ceiling 101 a of the living room 101 corresponding to each bed 102.

The care support system 1 described above includes a moving body detection unit 10 (at least one moving body detection unit 10) installed in at least one living room 101 and a management server 100a provided in the staff station 100 via a communication line 200. Are connected to communicate with each other.

[Motion detection unit]
Next, the details of the moving object detection unit 10 will be described. FIG. 3 is a block diagram showing a schematic configuration of the moving object detection unit 10. The moving body detection unit 10 is a unit that detects information on 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). Yes. Since the moving body detection unit 10 includes various sensors such as the above-described radio wave detection unit 30 and an optical detection unit 23 described later, it is also called a sensor box.

The image recognition system 20 includes an illumination unit 21, an illumination control unit 22, and an optical detection unit 23. The illumination unit 21 includes an LED (LightＬＥＤEmitting Diode) that emits infrared light (for example, near-infrared light) to enable photographing in the dark, and is provided at the center of the ceiling 101a of the living room 101. Located 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 portion 101a and the floor surface 101b. The illumination control part 22 is comprised, for example with CPU, and controls the illumination (infrared light emission) by the illumination part 21. FIG.

The optical detection unit 23 is an imaging unit that captures an image of the interior of the living room 101 under the illumination of the illumination unit 21 and is configured by a camera, for example. FIG. 4 is a block diagram illustrating a detailed configuration of the optical detection unit 23, and FIG. 5 schematically illustrates an example of an image acquired by photographing with the optical detection unit 23. The optical detection unit 23 is disposed adjacent to the illumination unit 21 in the center of the ceiling 101a (see FIG. 2) of the living room 101, and acquires an image of a viewpoint directly above that has a viewing direction immediately below by photographing. The optical detection unit 23 includes a lens 51, an image sensor 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 fisheye lens. As the super 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 care recipient 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 CCD (Charge Coupled Device) or CMOS (Complementary Metal Metal Oxide Semiconductor). The image sensor 52 is configured by removing the IR cut filter so that the state of the cared person can be detected as an image even in a dark environment. An output signal from the image sensor 52 is input to the AD conversion unit 53.

The AD conversion unit 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 the digital image signal output from the AD conversion unit 53 and executes 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 the image recognition unit 25 described later.

The control calculation unit 55 executes calculations such as AE (Automatic Exposure) related to the control of the image sensor 52 and controls the image sensor 52 such as exposure time and gain. Moreover, the control calculating part 55 performs control while performing calculations, such as a suitable light quantity setting and light distribution setting, with respect to the illumination part 21, as needed. 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 separate CPUs, for example. However, the image processing unit 54 and the control calculation unit 55 may be configured by a single CPU or by dedicated circuits that perform image processing and calculation processing. May be.

The image recognition system 20 described above 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 RAM (Random Access Memory), a ROM (Read Only Memory), a nonvolatile memory, and the like.

The image recognition unit 25 performs image recognition processing on the image data of the image acquired by the optical detection unit 23. More specifically, the image recognition unit 25 receives a signal after the image processing unit 54 of the optical detection unit 23 performs image processing, extracts the contour of the object, for example, and shapes it by a method such as pattern matching. An image recognition process for recognizing the image is executed. Thereby, the image recognition part 25 can recognize the state of the cared person in the living room 101.

Here, the state of the cared person in the living room 101 is assumed to be rising, getting out of bed, entering the floor, falling over, and the like. Waking up refers to the state from when the cared person wakes up to wake up on the bed. Getting out of bed refers to the state from when the cared person wakes up on the bed until it gets off the floor and leaves the bed. Entering the floor refers to the movement of the care recipient from the floor to the bed and lying down. Falling refers to an action in which the care recipient falls on the floor. The above-mentioned getting-up, getting-off, getting-in, falling-over is accompanied by the movement of the cared person's body (body movement), and the minute movement detected by the radio wave detection unit 30 (the minute movement of the body by breathing etc.) ).

In addition, the image recognition part 25 can also recognize the shape and position of the bed 102 or 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 emitting and receiving radio waves. The radio wave detection unit 30 radiates, for example, a 24 GHz band microwave from a radiating unit (not shown) toward the bed of each living room. The reflected wave reflected by Doppler and shifted by Doppler is received by a receiving unit (not shown). Thereby, the radio wave detection unit 30 can detect biological information (information such as a respiratory state, a sleep state, and a heart rate) of the cared person from the received reflected wave.

In addition, when the cared person is breathing (including during sleep), minute movements of the body due to the cared person's breathing (micromotion) occur. For this reason, detecting the care recipient's breathing state and sleep state is the same as detecting the care receiver's micromotion. From this, it can also be said that the radio wave detection unit 30 functions as a microscopic motion detection unit that detects microscopic motion of a care recipient (subject).

The unit control unit 40 controls the operations of the image recognition system 20 and the radio wave detection unit 30, and performs image processing and signal processing on information obtained from the image recognition system 20 and the radio wave detection unit 30, and results obtained Is a control board that outputs to the management server 100a as information on the status of the care recipient. 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 composed of a CPU that controls the operation of each unit in the moving object detection unit 10. The information processing unit 42 and the image recognition unit 25 may be configured by the above-described CPU (may be integrated with the main control unit 41), or may be another arithmetic unit or a circuit that performs a specific process. It may be configured.

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

The network cable (not shown) of the communication line 200 is electrically connected to the interface unit 43. Information relating to the status of the cared person detected by the moving object detection unit 10 based on images and microwaves is transmitted to the management server 100a via the interface unit 43 and the communication line 200.

[Supplemental information on 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 object detection unit 10 and the radio wave detection unit 30 in an attached state and a detached state of the front cover 11a with respect to a main body 11b described later of the housing 11. The radio wave detection unit 30 includes a sensor unit 31 and a radome lens 32.

The sensor unit 31 is a chip composed of 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 RFLSI (high frequency integrated circuit element), and a transmission antenna and a reception antenna for transmitting and receiving radio waves.

The radome lens 32 is a radio wave lens that protects the sensor unit 31 and controls (for example, narrows) the directivity of radio waves radiated from the sensor unit 31, and is located 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 positioned. For example, the surface 32a on the sensor unit 31 side is a flat surface, and the surface 32b on the opposite side to the sensor unit 31 is formed of a plano-convex lens having a convex shape on the radio wave radiation side. It is held by the holding part 34 so as to pass through the center. Therefore, the direction of the sensor unit 31 coincides with the direction of the main axis of the radome lens 32.

Here, the main axis of the radome lens 32 is an axis that passes through the center of curvature of the surface 32b of the radome lens 32 and is perpendicular to the surface 32a, and is synonymous with the optical axis or rotational symmetry axis. In addition, the angle that defines the “direction of the sensor unit 31” described above is such that the sensor unit 31 has a rotation axis in a direction perpendicular to a horizontal plane (here, the ceiling 101a of the living room 101 where the moving object detection unit 10 is installed). 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, but here, in order to facilitate understanding of the description, unless otherwise noted , And refers to the pitch angle.

Further, here, when considering two rotation axes perpendicular to each other in a plane parallel to the horizontal plane, the pitch angle that 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 the yaw angle that is the rotation angle when rotating around the rotation axis (for example, the front-rear direction) (the one rotation axis becomes the other rotation axis by rotation in a direction parallel to the horizontal plane). Therefore, both are treated as a pitch angle in a unified manner.

The casing 11 of the moving object detection unit 10 described above includes a front cover 11a located in front of the radome lens 32 (on the side opposite to the sensor unit 31) and the remaining main body 11b. The front cover 11a is detachably installed on the main body 11b. Thereby, when adjusting the direction of the sensor unit 31 to face the direction of the bed 102 so that the sensor unit 31 detects the respiratory state of the care recipient who is sleeping, as described later, It is possible to remove and adjust the cover 11a. When the adjustment of the orientation 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. And the fixing member 38 is rotatably supported by the support body 39 fixed to the main body 11b of the housing | casing 11 so that the direction of the sensor part 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 constituted by a Doppler sensor is obtained as time-series (continuous) amplitude data. By performing 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. For convenience, the power level on the vertical axis in FIG. 7 is indicated in an arbitrary unit corresponding to the intensity (dB) of the radio wave detected by the sensor unit 31. The noise level refers to the spectrum shown in FIG. 7, that is, the magnitude (power level) of a signal detected by the sensor unit 31 when the care receiver who is the detection target is not in the living room 101.

On the other hand, when the sensor unit 31 detects the respiratory state of the care recipient 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 such that the respiration signal is added. At this time, the ratio of the signal level at the breathing frequency (about 0.2 Hz (around 12 times / minute)) and the noise level becomes the S / N (signal to noise) ratio, and the larger this S / N ratio, The detection accuracy of the breathing state 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 respiration 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 (respiration signal) of the biological information of the care recipient. 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 examinations and analyzes by the inventors of the present application, it is known that the main factor that deteriorates the noise level is the 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 the radiated radio wave (transmitted wave). Originally, a Doppler sensor is a sensor that detects a reflected wave that is reflected back by a moving object, 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 the clutter signal by electrical processing using a filter or the like. However, when there is a reflective object in the vicinity of the radio wave transmission unit (transmission antenna) of the sensor, a clutter signal exceeding the capacity that can be canceled by the clutter cancellation circuit is generated.

FIG. 9 schematically shows several generation paths of clutter signals generated inside the moving object detection unit 10 shown in FIG. There are mainly the following three generation paths of the clutter signal.
(1) A path A in which a radio wave transmitted from the transmission antenna of the sensor unit 31 directly enters (leaks) into the reception 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 in the very vicinity of the transmission antenna, and directly enters the sensor unit 31. Path B.
(3) A path C in which the radio wave transmitted from the transmission antenna of the sensor unit 31 is reflected by the inner surface of the front cover 11a of the housing 11 that is a stationary object located in the vicinity of the transmission antenna and directly enters the sensor unit 31.

Among the above three paths A to C, the influence of the clutter signal generated in the path C has the greatest influence on the noise compared to the clutter signal generated in the other paths. This is suppressed to some extent by the clutter signal generated in the route A and the route B 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). Although the relative positional relationship between the sensor unit 31 and the front cover 11a is not fixed for the clutter signal generated in the path C (the direction of the sensor unit 31 varies depending on the position of the bed 102 in the living room 101). 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 diagram shows a case where the noise level is relatively low, and the lower diagram shows noise. The case where the level is relatively large is shown. In the figure, the “magnitude of the respiratory signal” on the horizontal axis represents a respiratory detection spectrum (for example, a respiratory frequency (near 0.2 Hz) in the Fourier transform spectrum of the detection signal shown in FIG. This corresponds to the integrated value (area) in the respiration frequency band of 0.5 Hz, and the person with a small respiration signal (for example, an elderly person) is to the left of the center of the horizontal axis (the person with a normal respiration signal magnitude). 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. The “frequency” on the vertical axis corresponds to the total number (frequency) of people indicating the magnitude of a certain respiratory signal. Moreover, the noise level shown in FIG. 10 is equivalent to the integral value in the said respiration detection area of the signal detected by the sensor part 31 when it is unattended.

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 reported). . 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 lost). ). Therefore, in order to increase the detection accuracy of the respiratory signal, it is necessary to suppress an increase in noise level due to the clutter signal.

FIG. 11 is a Fourier transform spectrum of a signal detected by the sensor unit 31 when there is no cared person in the living room 101, and shows a case where the clutter signal is large and a case where the clutter signal is small. Since noise generated by the clutter signal is white noise generated at all frequencies, when the clutter signal is large, the spectrum is such that the entire power level is offset upward compared to when the clutter signal is small.

FIG. 12 shows a Fourier transform spectrum of the detection signal when the respiratory signal of the care recipient is acquired, and shows a case where the clutter signal is larger 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 and the clutter signal is canceled 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. The clutter signal can be canceled. However, as shown in FIG. 12, when the power level of the respiration signal is smaller than the noise level, the respiration signal cannot be detected even if the subtraction process is performed because the respiration signal is buried in noise. In the care support system 1, since it is assumed that elderly persons whose respiratory signals are never large are included in the subject and the clutter signal is also quite large, the clutter signal is canceled by the subtraction process as in Patent Document 1. The method cannot be adopted. Therefore, it is necessary to reduce the clutter signal by a method other than the subtraction process.

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

FIG. 14 schematically shows the orientation of the sensor unit 31 that changes in accordance with 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 defined 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 shown when θ = 0 ° 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, in order to detect the respiratory state of the cared person P lying on the bed 102 by the sensor unit 31 while the cared person P is sleeping, the inside of the moving object detection unit 10 installed in the ceiling part 101a The sensor unit 31 is operated in the direction of the bed 102.

As shown in the figure, even if the orientation of the sensor unit 31 is changed in accordance with the position of the bed 102, the relative positional relationship (relative distance) between the sensor unit 31 (especially the transmission 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 (depending on the distance between the moving object detection unit 10 and the bed 102 and the direction of the bed 102 as viewed from the moving object detection unit 10), and the sensor unit 31 and the front cover 11a. This means that the relative distance between and changes.

Thus, 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 (front cover 11a) shown in FIG. Changes. This means that the magnitude of the clutter signal (amplitude and level of the synthesized wave) varies depending on the direction of the sensor unit 31, and the noise level detected by the sensor unit 31 varies depending on 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 radiation 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 the integral value of the breath detection interval in the Fourier transform spectrum of the signal detected by the sensor unit 31 when unattended. Since each of the radome angles θ1 to θ4 has a different relative distance between the sensor unit 31 and the front cover 11a, it can be seen that the noise level changes according to the radome angle as shown in FIG. In other words, the noise level depends on the radome angle. With such characteristics, the detected noise level varies (varies) depending on the positional relationship between the moving body detection unit 10 and the bed 102 (the direction of the set sensor unit 31), and the micro body movement detection is performed depending on the direction of the sensor unit 31. There will be a difference in ability.

[Concept of reducing 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 detected noise level 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 (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 (almost impossible) to change the position of the front cover 11 a for each direction of the sensor unit 31, and in the direction of the sensor unit 31. It is actually difficult to design the shape of the front cover 11a so that the noise level can be reduced.

So, go back to the nature of the wave and consider again. In the case of a wave, even if the position of the fixed end is the same, the magnitude of the synthesized wave can be reduced by changing the frequency (radiation frequency) of the transmission wave. FIG. 16 schematically shows waveforms of a transmission wave, a reflected wave, and a composite wave when the radiation 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 combined 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 synthesized wave is 30 to 40% smaller than that of the transmission wave (or reflected wave) than when the radiation frequency is A. This is because the phase of the transmission wave at the fixed end position is changed by changing the radiation frequency.

As shown in FIG. 16, if the position of the fixed end is the same, the magnitude of the synthesized wave, that is, the magnitude of the clutter signal changes when the radiation frequency of the transmission wave changes. Also show 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 radiation frequency A, the noise level increases as the radome angle increases. At the radiation frequency B, the noise level decreases as the radome angle increases. ing. As a result, when the radome angle is θ1 and θ2, the noise level is minimum at the radiation frequency A, and when the radome angle is θ3 and θ4, the noise level is minimum at the radiation frequency 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 emitting 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 radiation 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 of the first specific example. In the figure, for the sake of convenience, a part of the configuration of the image recognition unit 20 is omitted, but the configuration of the image recognition unit 20 is as shown in FIG. In the care support system 1 of the first specific example, the radio wave detection unit 30 described above further includes a storage unit 35, a radiation control unit 36, and an interface unit 37 in addition to the sensor unit 31, the radome lens 32, and the like. ing. The interface unit 37 is an interface for inputting / outputting information or control signals to / from the unit control unit 40, and includes an input / output port (terminal).

The storage unit 35 can detect biological information based on the noise level detected by the sensor unit 31 by the emission of radio waves for each different direction (here, radome angle) of the sensor unit 31 in the housing of the moving object detection unit 10. This is a memory for storing a table defining a specific radiation frequency that is smaller than a predetermined level (for example, the noise level is minimized). The storage unit 35 is composed of, 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, the radome angles θ1 and θ2 have the minimum noise level at the radiation frequency A, and the radome angles θ3 and θ4 have the minimum noise level 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 specified for the radome angles θ3 and θ4. The frequency is set. 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 the radio wave in the sensor unit 31, and is configured by a CPU, for example. In particular, the radiation control unit 36 can obtain 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. Switch to a specific radiation frequency corresponding to the direction (radome angle).

For example, when the radome angle is changed from θ2 to θ3 in accordance with the change of the position of the bed 102 in the living room 101, the radiation control unit 36 refers to the above table and specifies 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 part 31 radiates | emits a radio wave with the radiation frequency B after switching.

Here, whether or not the radome angle has been changed can be determined by the radiation control unit 36 by using image recognition of the captured image. That is, in the configuration in which the moving body detection unit 10 includes the optical detection unit 23 and the image recognition unit 25, image recognition (the shape of the bed 102) by the image recognition unit 25 is obtained from an image acquired by the optical detection unit 23 by photographing the inside of the living room 101. Recognition) allows the shape and position of the bed 102 to be recognized, whereby the sleeping place of the care recipient can be identified in the image. If the sleeping place can be specified in the image, the angle of view corresponding to the sleeping place, that is, the angle of view in the vertical direction and the horizontal direction of the sleeping place (position of the bed 102) in the image can be known. The sensor unit 31 is installed in the ceiling 101a of the living room 101 as the moving body 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 it corresponds to a sleeping place in the image. The angle of view may be considered to indicate the direction of the bed 102 as 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 the presence / absence of a change in the orientation of the sensor unit 31 (a change in the radome angle) using image recognition of the captured image.

As described above, according to the setting of the direction of the sensor unit 31 by the radiation control unit 36, the radiation frequency of the radio wave radiated from the sensor unit 31 is based on the table and the specific radiation corresponding to the direction of the sensor unit 31. Switch to frequency. Thereby, no matter which 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 biological information signal (breathing signal) to be detected is small, the signal can be reliably detected in a state where noise including clutter is reduced from the beginning. Therefore, the noise can be reduced and the detection accuracy in the sensor unit 31 can be increased without performing post-processing for subtracting the clutter signal as in the prior art. In addition, since the detected noise level is minimized in any direction of the sensor unit 31, it is possible to suppress 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 the main factor of the noise level includes radio waves that directly enter the sensor unit 31 through other paths (for example, radio waves that satisfy resonance conditions). It is. However, in the specific example 1, since the specific radiation frequency that minimizes the entire noise level is set including the noise caused by such a direct incident wave, the switching to the specific radiation frequency causes all routes to be changed. The generated clutter signals can be collectively reduced to reduce the overall noise, thereby reliably increasing the detection accuracy of the sensor unit 31.

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 (without depending on an instruction from the management server 100a) can perform internal processing of the moving object detection unit 10. Thus, switching to the specific radiation frequency according to the setting of the orientation of the sensor unit 31 can be performed.

In particular, in the configuration in which the moving body detection unit 10 includes the optical detection unit 23 and the image recognition unit 25, the radiation control unit 36 is based on the angle of view corresponding to the sleeping place (the position of the bed 102) in the captured image. The orientation 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. That is, it becomes possible for the moving body detection unit 10 (the radio wave detection unit 30) itself to switch the radiation frequency of the sensor unit 31 to the specific radiation frequency using the change or setting of the direction of the sensor unit 31 as a trigger.

In addition, since the radome lens 32 of the radio wave detection unit 30 is integrally provided via the sensor unit 31 and the holding unit 34, the direction of the sensor unit 31 together with the radome lens 32 depends on the position of the bed 102. Even if it changes, the detection accuracy in the sensor unit 31 can be increased by switching to the specific radiation frequency while appropriately controlling the directivity of the radio wave by the radome lens 32, and the orientation of the sensor unit 31 Variations in detection performance due to can be reduced.

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

The specific radiation frequency stored in the table is not limited to the radiation frequency that minimizes the noise level. The specific radiation frequency may be a radiation frequency such that the noise level detected by the sensor unit 31 is smaller 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, the noise level (Fourier) detected by the sensor unit 31 even at the radiation frequency P (Hz) between the radiation frequency A and the radiation frequency B at the radome angles θ1 and θ2. If the integral 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 higher 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 radome angles θ1 and θ2 compared to the radiation frequency A, and at the radiation frequency Q, the noise level increases at radome angles θ3 and θ4 compared to the radiation frequency B. However, since these noise levels are both 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, the noise level is lower than the level of the respiratory signal as shown in FIG. Largely, the detection accuracy of the respiration signal can be improved as compared with the case where the respiration signal is buried in the noise level.

In the above, the bed 102 in the living room 101 is assumed as a sleeping place of the care recipient, but the care receiver who does not install the bed 102 in the living room 101 and sleeps with a futon on the floor, The futon may be considered as a sleeping place. Even in this case, since the sleeping place 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 sleeping place 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 are the storage units described above. 35 and the function of the radiation control unit 36 may also be used.

[Specific Example 2]
FIG. 22 is a block diagram illustrating a configuration of the care support system 1 of the second specific example. In the second specific example, the table described in the first specific example is stored in the management server 100a of the care support system 1, and a request for switching to the specific radiation frequency grasped from the above table is sent from the management server 100a to the moving object detection unit 10 side. The radiation frequency of the sensor unit 31 is switched based on this switching request. More details are 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 illustrated in FIG. In addition to 32 (see FIG. 6 and the like), a radiation control unit 36 and an interface unit 37 are provided. The radiation control unit 36 controls the radiation of the radio wave in the sensor unit 31, but differs from the first specific example in that the radio wave radiation is controlled based on a control signal from a management control unit 111 (to be described later) of the management server 100 a. ing.

The management server 100a includes 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 / outputting information or control signals to / from the unit control unit 40 via the communication line 200, and includes an input / output port (terminal).

The management control unit 111 includes a CPU that controls the operation of each unit of the management server 100a. The memory | storage part 112 is a memory which memorize | stores the table which shows the corresponding | compatible relationship between a radome angle and specific radiation frequency shown in FIG. 19, for example, is comprised by the 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 orientation of the sensor unit 31.

In addition, a system user (administrator) owns (mobile) an external terminal 300 that can wirelessly communicate with the management server 100a via the communication line 200. Accordingly, 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 portable 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 system user can input 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 the specific radiation frequency corresponding to the input radome angle, and requests a control signal (setting command) for switching to the obtained specific radiation frequency. ) Is transmitted to the moving object detection unit 10. The moving body detection unit 10 receives the control signal, and the radiation control unit 36 switches the radiation frequency of the radio wave radiated from the sensor unit 31 to the specific radiation frequency based on the control signal. Thereby, the sensor part 31 radiates | emits an electromagnetic wave with the specific radiation frequency after switching.

In the care support system 1 of Example 2, since the management server 100a has the storage unit 112 that stores the table, it is not necessary to provide a large-capacity memory in the motion detection unit 10, and the motion detection unit 10 The manufacturing cost can be reduced and the size can be reduced. In addition, the management control unit 111 transmits a control signal for requesting switching to a specific radiation frequency obtained based on the table to the moving object detection unit 10, and in response to this, the radiation control unit 36 of the moving object detection unit 10 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 at the sensor unit 31 can be increased, and variation in detection performance due to the orientation of the sensor unit 31 can be reduced. The effect of can be obtained.

In addition, when the information related to the orientation of the sensor unit 31 is input by the input unit 113 or when the management control unit 111 receives the information from the external terminal 300, the management control unit 111 uses the sensor in the storage unit 112 based on the table. A specific radiation frequency corresponding to the direction of the unit 31 is obtained, and a control signal for 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, thereby obtaining the specific radiation frequency corresponding to the direction of the sensor unit 31. It can be determined based on a 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, as shown in the specific example 1, and based on it. The management server 100a may grasp the direction of the sensor unit 31. That is, the information acquired by the optical detection unit 23 and the image recognition unit 25 (the captured image and the sleeping place information specified in the image) is transmitted to the management server 100a, and the management control unit 111 is based on the information. The angle of view corresponding to the sleeping place in the image and the orientation of the sensor unit 31 may be grasped. And the management control part 111 calculates | requires the specific radiation frequency corresponding to the direction of the sensor part 31 based on the table memorize | stored in the memory | storage part 112, and gives the control signal which requests | requires the switch to the said specific radiation frequency to a moving body detection unit. 10 may be transmitted.

In this case, the management server 100 a (management control unit 111) does not receive any information regarding the orientation of the sensor unit 31 from the input unit 113 or the external terminal 300. The direction of the unit 31 is 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 make a request for switching to an appropriate specific radiation frequency (transmission of a control signal) to the moving object detection unit 10.

[Specific Example 3]
The care support system 1 of the specific example 3 is 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. It is the same. FIG. 23 illustrates an example of a table stored in the storage unit of the care support system 1 according to the third specific example. In the specific examples 1 and 2, the angle defining the direction of the sensor unit 31 is only the radome angle, but strictly speaking, it is necessary to consider the radome rotation angle. The radome rotation angle corresponds to the yaw angle when the sensor unit 31 rotates with the direction perpendicular to the horizontal plane (ceiling 101a) as the rotation axis. The radome angle described above corresponds to a pitch angle when the sensor unit 31 rotates with a direction parallel to the horizontal plane as a rotation axis. When the radome rotation angle changes, depending on the shape of the front cover 11a of the housing 11, the relative positional relationship (relative distance) between the sensor unit 31 and the front cover 11a changes, and as a result, depending on the radome rotation angle. The noise level changes.

Therefore, in the specific example 3, both the radome rotation angle and the radome angle are considered as the angles that define the direction of the sensor unit 31, and noise is detected for each direction of the sensor unit 31 defined by both the radome rotation angle and the radome angle. A specific radiation frequency that minimizes the level is set in advance, and the correspondence relationship is stored as a table in the storage unit (storage unit 35 or storage unit 112). The specific radiation frequency corresponding to the set direction of the sensor unit 31 is obtained from the table, and the sensor unit 31 is driven at the obtained specific radiation frequency (the radiation frequency is switched) as in the first or second example.

In order to store the relationship between the direction of the sensor unit 31 and the specific radiation frequency as a table by specifying the direction of the sensor unit 31 three-dimensionally using the yaw angle and the pitch angle as in the specific example 3, the sensor unit Improvement of detection accuracy in the sensor unit 31 by realizing switching to an appropriate specific radiation frequency according to the direction of the sensor unit 31 regardless of the direction in the room 101 in which the direction of the 31 is a three-dimensional space In addition, it is possible to reduce variations in detection performance due to the orientation of the sensor unit 31.

In addition, although the structure which the radio wave detection part 30 has the radome lens 32 was demonstrated above, the radome lens 32 should just be provided as needed, and installation of the radome lens 32 is also omissible. In the radio wave detection unit 30, when the radome lens 32 is not provided, the direction of the sensor unit 31 may be a direction perpendicular to the substrate 33 on which the sensor unit 31 is mounted. Further, the above-described “radome angle” may be read as “the pitch angle of the sensor unit 31”, and “radome rotation angle” may be read as “the yaw angle of the sensor unit 31”.

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

The embodiment of the present invention has been described above, but the scope of the present invention is not limited to this, and various modifications can be made without departing from the spirit 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 of the present embodiment described above can be expressed as follows, thereby producing the following effects.

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

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. Thereby, no matter what direction the sensor unit is set, the noise level detected by the sensor unit is smaller 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, unlike the prior art, noise can be reduced without performing post-processing of subtracting the clutter signal from the detection signal, and detection accuracy at the sensor unit can be increased. In addition, since the noise level is small regardless of the orientation of the sensor unit, it is possible to suppress variation in detection performance depending on the orientation of the sensor unit.

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

The moving body detection unit captures an image of a living room and acquires an image, and identifies a sleeping place by recognizing the position of a bed or a futon in the living room by image recognition from the image acquired by the imaging unit. An image recognizing unit configured to recognize the orientation of the sensor unit based on an angle of view corresponding to the sleeping place in the image acquired by the imaging unit, and the sensor 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 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 the bed or the like can be specified by image recognition from the image acquired by photographing the living room, and thereby the bedtime in the image You can see the vertical and horizontal (shooting) angle of view of the place. 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 breathing state while the subject is sleeping. It may be considered that the angle of view corresponding to the sleeping place indicates the direction of the sensor unit. Therefore, the radiation control unit grasps the direction of the sensor unit from the angle of view every time the sensor unit is set (adjusted), even if no information on the direction of the sensor unit is input from the 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 moving object detection unit, the moving object detection unit includes the radiation control unit, and the management server stores the storage unit and the storage unit. A management control unit that transmits a control signal that requests switching to the specific radiation frequency obtained based on the table to the moving object detection unit, and the radiation control unit of the moving object detection unit includes the management control Based on the control signal transmitted from the unit, the radiation frequency of the radio wave radiated from the sensor unit may be switched to the specific radiation frequency.

Since the management server has a storage unit that stores the table, it is not necessary to provide a large-capacity memory in the motion detection unit, and the manufacturing cost and size of the motion detection unit can be reduced. Further, the management control unit of the management server transmits a control signal requesting switching to the specific radiation frequency obtained based on the table to the moving object detection unit, and the radiation control unit of the moving object detection unit is based on the control signal. The radiation frequency of the sensor unit is switched to the specific radiation frequency. Therefore, in the 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, for example, the detection accuracy at the sensor unit can be increased without performing a subtraction process.

The management server includes an input unit for inputting information related to the orientation of the sensor unit, and the management control unit is configured to input the sensor unit based on the table when the information is input by the input unit. The specific radiant frequency corresponding to the direction 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 make a request for switching to an appropriate specific radiation frequency (transmission of a control signal) to the moving object detection unit.

The management control unit obtains the specific radiation frequency corresponding to the direction of the sensor unit based on the table when receiving information on the direction of the sensor unit from an external terminal capable of communicating with the management server. The control signal may be transmitted to the moving object detection unit. In this case, the management control unit grasps the direction of the sensor unit from the information received from the external terminal (for example, a multi-function mobile terminal), and obtains 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 make a request for switching to an appropriate specific radiation frequency (transmission of a control signal) to the moving object detection unit.

The moving body detection unit captures an image of a living room and acquires an image, and identifies a sleeping place by recognizing the position of a bed or a futon in the living room by image recognition from the image acquired by the imaging unit. An image recognizing unit that further includes an angle of view corresponding to the sleeping place in the image based on the image and the sleeping place information output from the moving body detection unit. 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 the bed or the like can be specified by image recognition from the image acquired by photographing the living room, and thereby the bedtime in the image You can see the vertical and horizontal (shooting) angle of view of the place. 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 breathing state while the subject is sleeping. It may be considered that the angle of view corresponding to the sleeping place indicates the direction of the sensor unit. Therefore, the management server (management control unit) is based on information (captured image and sleeping place information) output from the motion detection unit even if no information on the orientation 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 make a request for switching to an appropriate specific radiation frequency (transmission of a control signal) to the moving object detection unit.

The angle that defines the orientation of the sensor unit is a yaw angle when the sensor unit rotates with a direction perpendicular to the horizontal plane as a rotation axis, and when the sensor unit rotates with a direction parallel to the horizontal plane as a rotation axis. The pitch angle may be included. 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 is the same regardless of the direction of the sensor unit in the 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 that the detection accuracy at the sensor unit can be increased without performing subtraction processing.

The system may further include a radome lens that is provided integrally via the sensor unit and the holding unit and controls the directivity of the radio wave radiated from the sensor unit. In this case, no matter how the direction of the sensor unit changes with the radome lens, subtraction processing is performed by switching to a specific radiation frequency corresponding to the direction of the sensor unit while appropriately controlling the directivity of the radio wave with the radome lens. It is possible to obtain the above-described effect such that the detection accuracy at the sensor unit can be increased without performing the above.

The table may define the specific radiation frequency that minimizes the noise level for each different direction of the sensor unit in the housing. Switching to a specific radiation frequency corresponding to the direction of the sensor unit minimizes the noise level detected by the sensor unit due to radio wave radiation. Therefore, a signal to be detected by the sensor unit (a detection signal of biological information to be observed) ) Can be acquired reliably.

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 Case 11a Front cover 23 Optical detection part (imaging part)
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)

1. A sensor unit that is arranged in a housing of a moving object detection unit installed in the subject's room and detects biological information of the subject by radiating and receiving radio waves;
   A radiation control unit for controlling the radiation frequency of the radio wave;
   Stores a table defining a specific radiation frequency such that the noise level detected by the sensor unit is lower than a predetermined level at which the biological information can be detected for each different orientation of the sensor unit in the housing. And a storage unit
   The radiation control unit is configured to obtain the radiation frequency of the radio wave radiated from the sensor unit based on the table in accordance with the setting of the direction of the sensor unit, and the specific radiation corresponding to the direction of the sensor unit. Care support system that switches to frequency.
2. The care support system according to claim 1, wherein the moving object detection unit includes the radiation control unit and the storage unit.
3. The moving object detection unit is
   An image capturing unit that captures an image of a room and acquires an image;
   An image recognition unit that recognizes the position of a bed or a futon in the living room by image recognition from the image acquired by the imaging unit, and identifies 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 emits the radio wave radiated from the sensor unit. The care support system according to claim 2, wherein the frequency is switched to the specific radiation frequency corresponding to the direction of the sensor unit, which is obtained based on the table.
4. The system further includes a management server that manages information output from the motion detection unit,
   The moving object detection unit includes the radiation control unit,
   The management server is
   The storage unit;
   A management control unit that transmits a control signal that requests switching to the specific radiation frequency obtained based on the table stored in the storage unit to the moving object detection unit;
   The radiation control unit of the moving object detection unit switches the 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. As described in the care support system.
5. The management server includes an input unit for inputting information on the orientation of the sensor unit,
   The management control unit obtains the specific radiation frequency corresponding to the direction of the sensor unit based on the table when the information is input by the input unit, and transmits the control signal to the moving object detection unit. The care support system according to claim 4.
6. The management control unit obtains the specific radiation frequency corresponding to the direction of the sensor unit based on the table when receiving information on the direction of the sensor unit from an external terminal capable of communicating with the management server. The care support system according to claim 4, wherein the control signal is transmitted to the moving object detection unit.
7. The moving object detection unit is
   An image capturing unit that captures an image of a room and acquires an image;
   An image recognition unit that recognizes the position of a bed or a futon in the living room by image recognition from the image acquired by the imaging unit, and identifies a sleeping place;
   The management control unit grasps the angle of view corresponding to the sleeping place in the image and the direction of the sensor unit based on the image and the sleeping place information output from the moving object detection unit, The care support system according to any one of claims 4 to 6, 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 object detection unit.
8. The angle that defines the orientation of the sensor unit is a yaw angle when the sensor unit rotates with a direction perpendicular to the horizontal plane as a rotation axis, and 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 any one of claims 1 to 8, further comprising a radome lens that is provided integrally via the sensor unit and the holding unit and controls the directivity of the radio wave radiated 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 that minimizes the noise level for each different orientation of the sensor unit in the housing. system.

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