JP4058286B2 - Monitoring device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a monitoring device that monitors a monitoring object, and more particularly to a monitoring device for monitoring changes in sleep and breathing of a sleeping person.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a monitoring device for monitoring a sleeper's respiration change, a device for monitoring a sleeper's respiration change based on a time transition of a pressure distribution detected by a load sensor or a pressure sensor has been proposed.
[0003]
[Problems to be solved by the invention]
However, according to the conventional apparatus as described above, the monitoring device has a very small signal to be measured, and therefore, a high-performance signal amplifier or some kind of signal processing is required to acquire and detect a stable signal. It was a complicated and large-scale system.
[0004]
Therefore, the present invention aims to provide a simple monitoring device as well as accurately detecting the state of a sleeping person.
[0005]
[Means for Solving the Problems]
  In order to achieve the above object, the monitoring apparatus 1 according to the first aspect of the present invention is a variable having a correlation with the distance to the monitoring object 2 in the monitoring object region 50 as shown in FIGS. A sensor 11 that detects a distance; a computing device 22 that computes a distance-related value based on the variable output from the sensor 11; and a presence or absence of a shape change of the monitoring object 2 based on the computed distance-related value. The determination device 23 is configured to determine that the monitoring target 2 has a periodic shape change when a periodic change in the distance-related value is detected.The determination device 23 determines that the distance-related value is a first threshold Th _1x Above, the first threshold Th _1x The second threshold value Th which is a larger value _2x The monitoring object 2 is configured to determine that the first shape change has occurred in the following cases; the determination device 23 determines that the distance-related value is a second threshold Th _2x Larger, the second threshold Th _2x The third threshold value Th which is a larger value _3x The monitoring object 2 is configured to determine that a second shape change different from the first shape change has occurred at the following time.ing. Here, as described in claim 2, in the monitoring device according to claim 1,,Typely, the monitored object 2 is a sleeping person, and the periodic shape change is based on the sleeping person's breathing. Claims3As claimed in2The monitoring apparatus described in (1) includes a breathing pattern storage unit 26 (see, for example, FIG. 4) that stores the waveform pattern of normal sleep and the waveform of abnormal breathing of the sleeper; May be configured to collate the detected periodic change in the distance-related value with a respiration pattern stored in the respiration pattern storage unit 26 (see, for example, FIG. 4) to determine the respiration waveform pattern.. SupervisorThe visual target object 2 is a sleeping person, for example.
[0006]
If comprised in this way, it will be provided with the sensor 11, the arithmetic unit 22, and the judgment apparatus 23, and the judgment apparatus 23 will be the 1st threshold value Th when the said distance relevant value is._1xAbove, the first threshold Th_1xThe second threshold value Th which is a larger value_2xSince it is configured to determine that the monitoring object 2 has undergone the first shape change at the following time, for example, the sleep of a sleeping person can be detected. In addition, the determination device 23 determines that the distance-related value is a second threshold Th._2xLarger, the second threshold Th_2xThe third threshold value Th which is a larger value_3xAt the following time, since it is determined that the monitoring object 2 has a second shape change different from the first shape change, for example, the body movement of a sleeping person can be detected. Thereby, not only the change of a sleeping person can be detected accurately, but also a simple monitoring device 1 can be provided.
[0007]
  And claims4As claimed inAny one of claims 1 to 3In the monitoring device 1 described in the above, the determination device 23 determines that the distance-related value is a third threshold Th._3xWhen the shape change of the monitoring object 2 cannot be detected within the first predetermined time after exceeding the above, it may be determined that the monitoring object 2 has come out of the monitoring object region 50.
[0008]
With this configuration, the determination device 23 determines that the distance-related value is the third threshold Th._3xIf the change in the shape of the monitored object 2 cannot be detected within the first predetermined time after exceeding the threshold, it is determined that the monitored object 2 has gone out of the monitored area 50. it can.
[0009]
  Abovelike,For example, as shown in FIG. 1 and FIG.In the monitoring device 1, the determination device 23 detects a periodic change in the distance related value.Periodic shape change in monitoring object 2 (Third shape change)Configured to determine that there wasHas been.
[0010]
  If comprised in this way, a sleeper's respiration can be detected correctly. The determination device 23 is configured to monitor the period of the periodic change based on the detected periodic change. In addition, the said period is the concept containing the respiratory rate of a sleeper. Moreover, the monitoring object 2 is a thing which changes periodically, and the thing which changes periodically is a concept including animals, such as a person. And claims5As claimed inAny one of claims 1 to 4In the monitoring device 1 described in the above, the determination device 23 determines that the distance-related value is a third threshold Th._3xIt may be configured to determine that the fourth change in the shape of the monitoring object 2 has occurred when the value exceeds.
[0011]
  And claims6As claimed in1To claims5In the monitoring device 1 described in any one of the above, when the determination device 23 determines that there is a change in the shape of the monitoring object 2 for a second predetermined time, the monitoring object 2 is in the monitoring object region. It may be configured to determine that it is within 50.
[0012]
If comprised in this way, when the state judged that there exists a shape change of the monitoring target object 2 continues for the 2nd predetermined time, it will determine that the monitoring target object 2 exists in the monitoring object area | region 50, For example, a sleeper Can be detected.
[0013]
  And claims7As claimed in6In the monitoring device 1 described in the above, the determination device 23 determines that the distance-related value is a first threshold Th._1xWhen it is smaller, the monitoring object 2 is configured to determine that there is no shape change, and after determining that the monitoring object 2 is in the monitoring object region 50, a state in which it is determined that there is no further shape change is the third state. It is good to comprise so that it may judge that the monitoring target object 2 is a dangerous state when it continues for this predetermined time.
[0014]
With this configuration, when it is determined that the monitoring object 2 is in the monitoring object region 50 and the state in which it is determined that there is no change in shape continues for a third predetermined time, the monitoring object 2 is dangerous. Since it is determined that the patient is in a state, for example, a dangerous state such as a sleep stop of a sleeping person can be determined, and the reliability is high.
[0015]
  And claims8As claimed in1To claims7In the monitoring device 1 according to any one of the above, when the state in which the determination device 23 determines that there is the second shape change continues for a fourth predetermined time, the monitoring object is in a dangerous state. It is good to comprise so that it may judge.
[0016]
  If comprised in this way, when the state judged that there exists the said 2nd shape change will continue for the 4th predetermined time, it will judge that the said monitoring target object is a dangerous state, For example, a sleeping person suffers. Highly reliable because it can judge dangerous situations such as rampage.
[0017]
  And claims9As claimed in7 orClaim8The monitoring device 1 described above includes an alarm unit 40 that issues an alarm; the determination device 23 is configured to transmit an alarm signal to the alarm unit 40 when it is determined that the monitored object 2 is in a dangerous state. Good.
[0018]
If comprised in this way, it will be provided with the alarm means 40, and when the judgment apparatus 23 judges that the monitoring target object 2 is a dangerous state, since an alarm signal is transmitted to the alarm means 40, for example, a sleeper is dangerous. When it is in a bad state, an alarm can be issued and the reliability is high.
[0019]
  BookThe monitoring device 1 according to the invention includes a sensor 11 that detects a variable having a correlation with the distance to the monitoring target object 2 in the monitoring target region 50, as shown in FIGS. A calculation device 22 for calculating a distance-related value based on the variable; and a determination device 23 for determining the presence or absence of a shape change of the monitored object 2 based on the calculated distance-related value; The distance related value is a third threshold Th._3xWhen the shape change of the monitored object 2 cannot be detected within the first predetermined time after exceeding the threshold value, it is determined that the monitored object 2 has gone out of the monitored area 50May.
[0020]
If comprised in this way, since the sensor 11, the calculating device 22, and the judgment apparatus 23 are provided, a distance related value will be calculated based on the said variable output from the sensor 11, and based on the calculated distance related value Then, since the presence or absence of the shape change of the monitoring object 2 is determined, for example, a change in the sleeping person can be detected. Further, the determination device 23 determines that the distance related value is a third threshold Th._3xWhen the shape change of the monitored object 2 cannot be detected within the first predetermined time after exceeding, it is determined that the monitored object 2 has gone out of the monitored area 50. It can be detected. Thereby, not only the change of a sleeping person can be detected accurately, but also a simple monitoring device 1 can be provided.
[0021]
  And claims5As claimed in1 to 4In the monitoring device 1 according to any one of the above, the determination device 23 determines that the distance-related value is a third threshold Th._3xIt may be configured to determine that the fourth change in the shape of the monitoring object 2 has occurred when the value exceeds.
[0022]
If comprised in this way, the said distance relevant value will be 3rd threshold value Th._3xWhen it exceeds, it is determined that the fourth change in the shape of the monitored object 2 has occurred, so that it is possible to detect body movements such as rising of a sleeping person, for example.
[0023]
  And claims10Claims 1 to9In the monitoring device 1 according to any one of the above, the calculated distance-related value may be a time change of the variable or an absolute value of the time change.
[0024]
  And claims11Claims 1 to10In the monitoring device 1 described in any one of the above, for example, as illustrated in FIGS. 6 and 7, the sensors 11 and 30 a include a light irradiation unit 31 a that irradiates the monitoring target 2 with a light beam and a light irradiation unit 31 a. An image forming optical system 37a for forming an image of the light irradiation pattern generated on the monitoring object 2, and an image forming optical system 37a arranged in the vicinity of an image forming position by the image forming optical system 37a. A light receiving surface 38 that is divided into a plurality of light receiving areas 38a and 38b for receiving image pattern light; and further receives signals from the light receiving areas 38a and 38b, and each light receiving area based on the received signals. A position information output device 39a configured to compare the intensities of the image forming pattern light incident on 38a and 38b with each other and output the image forming position information of the image forming pattern corresponding to the distance to the monitoring object 2 is provided. I have.
[0025]
If comprised in this way, since the sensors 11 and 30a have the light irradiation means 31a, the imaging optical system 37a, and the light-receiving surface 38 divided | segmented into the some light-receiving area 38a, 38b, it is a circuit structure, for example The monitoring device 1 can be made inexpensive and simple.
[0026]
  And claims12Claims 1 to10In the monitoring device 1 described in any one of the above, the sensors 11 and 30b include the light irradiation unit 31b that irradiates the monitoring target 2 with a light beam, and the light irradiation generated on the monitoring target 2 by the light irradiation unit 31b. An imaging optical system 37b that forms an image of the pattern, and a light receiving means 36 that is disposed in the vicinity of the imaging position by the imaging optical system 37b and receives the imaging pattern light by the image of the imaged light irradiation pattern. Yes, based on the imaging position of the imaging pattern light imaged on the light receiving means 36, the imaging position information of the imaging pattern corresponding to the distance to the monitoring object 2 is output. A position information output device 39b is provided.
[0027]
  If comprised in this way, the sensors 11 and 30b have the light irradiation means 31b, the imaging optical system 37b, and the light-receiving means 36, and the imaging position of the imaging pattern light imaged on the light-receiving means 36 Since the imaging position information of the imaging pattern corresponding to the distance to the monitoring object 2 is output based on the above, it is possible to make the monitoring apparatus 1 inexpensive and simple.
  Claims13As shown in FIGS. 1 and 4, for example, the monitoring device 1 according to the invention relates to a sensor 11 that detects a variable having a correlation with the distance to the monitoring target 2 in the monitoring target region 50; A calculation device 22 for calculating a distance-related value based on the variable to be determined; and a determination device 23 for determining the presence or absence of a shape change of the monitored object 2 based on the calculated distance-related value; Is configured to determine that there is a periodic shape change in the monitored object 2 when a periodic change in the distance-related value is detected; the monitored object 2 is a sleeper, and the periodic object The shape change is based on the sleep of the sleeper; and includes a breathing pattern storage unit 26 (see, for example, FIG. 4) that stores the sleeper's normal breath waveform pattern and abnormal breath waveform pattern; 23 ( For example, in FIG. 4, the detected periodic change in the distance-related value is compared with the respiratory pattern stored in the respiratory pattern storage unit 26 (for example, see FIG. 4) to determine the pattern of the respiratory waveform. Configured; the determination device 23 is configured to determine that the monitored object 2 is in a dangerous state when the determined respiration waveform pattern is the abnormal respiration waveform pattern.
  And claims14As claimed in13The monitoring device 1 described above includes an alarm unit 40 that issues an alarm; the determination device 23 is configured to transmit an alarm signal to the alarm unit 40 when it is determined that the monitored object 2 is in a dangerous state. Good.
[0028]
  And claims15Claims 1 to14In the monitoring device 1 described in any one of the above, it is preferable to provide a plurality of sensors 11. If comprised in this way, since the sensor 11 is provided with two or more, the change of a sleeper can be detected more correctly.
[0029]
In addition, the monitoring device 1 may include presence detection means 41 that detects the monitoring target object 2 existing in or near the monitoring target area 50. If comprised in this way, when the presence detection means 41 cannot detect presence of the sleeping person 2 in the monitoring object area | region 50 or the monitoring object area | region 50 and its vicinity, the power of the monitoring apparatus 1 can be turned off, for example. So you can save power.
[0030]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. In addition, in each figure, the same code | symbol or a similar code | symbol is attached | subjected to the mutually same or equivalent member, and the overlapping description is abbreviate | omitted.
[0031]
FIG. 1 is a schematic perspective view of a monitoring device 1 according to an embodiment of the present invention. In FIG. 1A, a monitoring area 50 as a monitoring target area is set on the upper surface of the bed 6. Further, as shown in FIG. 1B, a sleeping person 2 as a monitoring object lies on the bed 6. Further, a bedding 3 is further hung on the sleeping person 2 and covers a part of the sleeping person 2 and a part of the bed 6. That is, when the sleeping person 2 is present on the bed 6 (is present), the monitoring device 1 monitors the upper surface of the bedding 3. When the bedding 3 is not used, the monitoring device 1 monitors the body part of the sleeping person 2 itself. The monitoring area 50 will be described later with reference to FIG.
[0032]
On the other hand, as shown in FIG. 1A, a distance sensor 11 is installed on the ceiling 4 as a sensor for detecting distance information as a variable having a correlation with the distance to the sleeping person 2 in the monitoring area 50. ing. In the present embodiment, there are a plurality of distance sensors 11. In the present embodiment, the distance information is a distance value that is the distance itself, or an output value corresponding to the distance value. Hereinafter, these are simply referred to as distances. Hereinafter, embodiments will be described in terms of distance.
[0033]
The plurality of distance sensors 11 are preferably installed on the ceiling 4 via the housing 10. By doing so, it is not necessary to install the plurality of distance sensors 11 on the ceiling 4 one by one, so that the installation is simple. A plurality of distance sensors 11 are installed in the housing 10 corresponding to a plurality of target points 5 (ranging points). In other words, the distance sensor 11 is installed in the number corresponding to the target point 5 and further installed toward the corresponding target point 5. The target point 5 will be described later with reference to FIG. In the present embodiment, the casing 10 (distance sensor 11) is installed on the ceiling 4. However, if there is a wall, it may be a wall, and the installation location is appropriately determined according to the purpose and specifications of the monitoring device. It's okay.
[0034]
Further, as shown in FIG. 2, the housing 10 may be installed on a movable stand 7. By doing in this way, installation of a plurality of distance sensors 11 becomes easy. For example, it can be installed at a necessary place when necessary in a hospital or the like, which is convenient.
[0035]
An example of the arrangement of the target points 5 will be described with reference to the schematic plan view of FIG. A plurality of target points 5 are arranged in the monitoring area 50. The target points 5 are preferably arranged in two or more rows in the monitoring area 50. FIG. 3A shows a case where the plurality of target points 51a to 54c corresponding to the plurality of distance sensors 11 are arranged so as not to overlap with the adjacent target points 51a to 54c, respectively.
[0036]
In this case, for example, as shown in the drawing, a plurality of target points 5 are located in the monitoring area 50 in the vicinity of the outer periphery of the bed 6, and the target points 51 a, 51 b, 51 c, 54 a, 54 b, 54 c are located in the center of the bed 6. Near the part, the target points 52a, 52b, 52c, 53a, 53b, 53c (hereinafter simply referred to as the target point 5 when not distinguished from each other) are arranged so as not to overlap each other. Moreover, as shown in the figure, the target points 5 are preferably arranged in a grid pattern. The plurality of target points 5 are preferably arranged in a range that covers the positions that the abdomen, chest, back, and shoulders of the sleeping person 2 on the bed 6 (bedding 3) can take during sleeping. In the present embodiment, the number to be arranged is 4 rows and 3 columns (hereinafter referred to as 4 × 3) in the figure, but may be appropriately determined depending on conditions such as a place to be monitored and a sleeping person 2, for example, 3 × 3, It may be 4 × 4 or 2 × 2.
[0037]
Further, with this arrangement, the monitoring area 50 can be widened even with a relatively small number of distance sensors, so that the efficiency is high. That is, since the monitoring area 50 in a necessary range can be monitored by a relatively small number of distance sensors 11, the monitoring apparatus 1 (see FIG. 1) having a small size and high efficiency can be obtained. Further, even when an irradiation type sensor that measures the distance by irradiating a light flux as described later is used as the distance sensor 11, the distance sensor 11 corresponding to the adjacent target point 5 does not irradiate simultaneously as described later. Thus, the monitoring apparatus 1 can be configured more simply.
[0038]
Moreover, as shown in the arrangement example of FIG. 3B, adjacent target points 5 may overlap. In this way, the blind spots in the monitoring area 50 can be reduced, which is effective for more accurate monitoring. At this time, when an irradiation type sensor that irradiates light to the distance sensor 11 and measures the distance, for example, it is necessary to control the distance sensor 11 corresponding to the overlapping target points 5 not to irradiate simultaneously. This is because, for example, when irradiation light is irradiated from a plurality of distance sensors 11 at the same time, the irradiation light irradiated from other distance sensors 11 is mixed with the irradiation light that should originally be received and is influenced by each other. This is because it becomes difficult to measure the distance.
[0039]
In addition, the distance sensor 11 is configured so that the wavelength of the light beam to be projected is different for each sensor as will be described later, and at the same time, transmission corresponding to the beam light projected to the light receiving lens 37a described later by means such as coating. When the wavelength band is allowed to pass, it is not necessary to control so that the adjacent target points 5 do not irradiate even if they overlap. In addition, when the distance sensor 11 blinks the light source of the light flux to be radiated at a constant frequency different for each distance sensor 11, and a signal having only that frequency is provided with an electrical bandpass filter described later. Therefore, it is not necessary to perform control so as not to irradiate simultaneously even if adjacent target points 5 overlap.
[0040]
An example of the configuration of the monitoring device 1 will be described with reference to FIG. The monitoring device 1 includes a housing 10 in which a plurality of distance sensors 11 are installed, and a control device 20. The control device 20 is typically a personal computer or a microcomputer. The plurality of distance sensors 11 are connected to the control device 20 and configured to output the distance to the control device 20. The distance may be acquired from each distance sensor 11 in time series. Moreover, although the distance sensor 11 and the control apparatus 20 are shown as separate bodies in the drawing, they may be configured as a single unit. The distance sensor 11 is installed in the housing 10 in 4 × 3.
[0041]
Typically, the distance sensor 11 is installed in parallel with the housing 10, but the housing 10 may be curved like a housing 10 ′ shown in the schematic diagram of FIG. 5. In this case, the distance sensor 11 is installed along this curve. By using such a casing 10 ′, it is possible to easily ensure a wide monitoring area 50 even if it is downsized. Further, even if the housing 10 'is small, it is possible to easily install the distance sensor 11 so that the adjacent target points 5 do not overlap, so that the device can be downsized.
[0042]
Here, the distance sensor 11 will be further described. Examples of the distance sensor 11 to be used include an infrared irradiation type distance sensor, an ultrasonic sensor, an electromagnetic pulse distance sensor, and a passive optical distance sensor. Among these, an infrared irradiation type distance sensor, an ultrasonic sensor, and an electromagnetic pulse distance sensor are irradiation type sensors. Further, as described above, it is preferable to use a relatively simple and inexpensive distance sensor 11 as used in an autofocus camera, for example. By using such a distance sensor 11, the monitoring device 1 can be configured simply and inexpensively. In this embodiment, a case where an infrared irradiation type distance sensor is used will be described.
[0043]
Hereinafter, an infrared irradiation type distance sensor will be described with reference to FIG. Here, an infrared irradiation type distance sensor 30 (hereinafter referred to as an infrared distance sensor 30) as an example of the distance sensor 11 will be described. The infrared distance sensor 30 is a so-called active optical sensor. In addition, the infrared distance sensor 30 includes one using a photodetector (hereinafter referred to as multi-segment PD) divided into a plurality of light receiving regions and one using a position detection element (hereinafter referred to as PSD). Hereinafter, an infrared distance sensor 30a using a multi-segment PD and an infrared distance sensor 30b using a PSD will be described. When these are not particularly distinguished, they are simply referred to as an infrared distance sensor 30.
[0044]
First, as shown in the block diagram of FIG. 6, the infrared distance sensor 30 a using the multi-segment PD includes an infrared light irradiation unit 31 a as a light irradiation unit that irradiates the sleeping person 2 with a light beam, an infrared light reception unit 32 a, A sensor control unit 33a that controls the entire infrared distance sensor 30a is included. The sensor control unit 33a may be provided in the control unit 21 of the control device 20 (see FIG. 4).
[0045]
The infrared light irradiation unit 31a is provided with an infrared LED 34a and an irradiation lens 35a, and a light beam of infrared light irradiated from the infrared LED 34a (hereinafter referred to as an appropriate beam) is thinly parallel through the irradiation lens 35a. The sleeping person 2 is irradiated as a luminous flux. Here, the parallel light flux only needs to be substantially parallel, and includes a nearly parallel light flux. The infrared light receiving unit 32a includes a light receiving lens 37a as an image forming optical system for forming an image of a light irradiation pattern generated on the sleeping person 2 by the infrared light irradiating unit 31a, and the vicinity of an image forming position by the light receiving lens 37a. And a multi-segment PD 38 as a light-receiving surface divided into a plurality of light-receiving regions that receive the imaging pattern light based on the image of the light irradiation pattern that has been formed. Here, the description will be made assuming that the number of divisions of the multi-division PD 38 is two divisions (hereinafter referred to as “two-division PD 38”).
[0046]
Further, the infrared distance sensor 30a receives a signal from each light receiving area, compares the intensity of the image pattern light incident on each light receiving area based on the received signal, and corresponds to the distance to the sleeping person 2. A position information output unit 39a serving as a position information output device configured to output image position information of an image forming pattern to be output. The position information output unit 39a is provided in the sensor control unit 33a. Here, the light beam is, for example, beam light, and the light irradiation pattern by the light beam is a beam light spot. The imaging pattern light is the light incident on the two-divided PD 38 out of the reflected light from the sleeping person 2 of the beam light spot generated on the sleeping person 2, and the imaging pattern is imaged by the light receiving lens 37a. It is the image of the beam light spot produced | generated on the sleeping person 2 made. That is, here, the imaging pattern is a substantially circular image.
[0047]
Here, the two-divided PD 38 will be described with reference to FIGS. As shown in FIG. 7, the two-divided PD 38 is divided into two light receiving regions 38a and 38b and placed in parallel on the substrate 38c. The dividing direction is a direction approximately perpendicular to the moving direction of the imaging pattern due to the change in distance (the left-right direction in the figure). In other words, the divided light receiving regions 38a and 38b are divided so as to be aligned along the moving direction of the imaging pattern due to the change in distance.
[0048]
In the light receiving areas 38a and 38b, the imaging pattern light reflected by the sleeping person 2 and imaged by the light receiving lens 37a forms an image across the light receiving areas 38a and 38b, thereby generating a current in each light receiving area. To do.
[0049]
As shown in FIG. 8, an IV conversion amplifier 39d is connected to each of the light receiving regions 38a and 38b. The current values of the currents generated in the light receiving regions 38a and 38b are converted into voltage values by the IV conversion amplifier 39d, respectively, and input to the comparison circuit 39c. The comparison circuit 39c calculates the imaging position information, that is, the distance of the imaging pattern by taking these ratios. The IV conversion amplifier 39d and the comparison circuit 39c are both provided in the position information output unit 39a. In the case of the two-divided PD 38, the light receiving area of the two-divided PD 38 may be set so that the light receiving area of the two-divided PD 38 is larger than the diameter (pattern diameter) of the substantially circular imaging pattern. In this way, even if the pattern diameter is increased by changing the distance of the object, the image formation pattern is not lost from the two-segment PD 38, and the distance can be measured stably and accurately.
[0050]
Here, since the two-divided PD 38 generates a current in proportion to the amount of light (intensity) of the imaging pattern light, the voltage value output from the light receiving regions 38a and 38b and converted by the IV conversion amplifier 39d is the basic value. Thus, it can be regarded as the area of the image formation pattern formed on the light receiving regions 38a and 38b. That is, the ratio of the voltage values can be regarded as the area ratio of the image formation pattern formed on the light receiving regions 38a and 38b. This area ratio changes when the imaging pattern moves due to a change in the distance of the object. That is, the area ratio can be regarded as a value corresponding to the position of the imaging pattern. Thereby, the area ratio, that is, the voltage value ratio can be used as the imaging position information, that is, the distance of the imaging pattern.
[0051]
FIG. 9 shows an example of the relationship between the area ratio and the object distance. Here, the imaging pattern on the light receiving area 38a is defined as area A and the imaging pattern area B of the light receiving area 38b. The base line length is the distance between the optical axes of the irradiation lens 35a and the light receiving lens 37a, the beam light diameter is the diameter of the beam light irradiated from the irradiation lens 35a, and the sensor installation height is from the light receiving lens 37a to the monitoring region 50 (bed 6 upper surface) and the focal distance are the focal distance of the light receiving lens 37a, and the image distance is the distance from the light receiving lens 37a to the imaging surface of the two-part PD 38. As the two-segment PD, one having a light receiving area of 4 mm × 4 mm × 2 is used.
[0052]
In the above description, the number of divisions of the multi-division PD 38 has been described as two divisions, but may be two or more divisions. The multi-divided PD may be one in which non-divided PDs are arranged side by side.
[0053]
As shown in FIGS. 10 and 11, here, the description will be made assuming that the number of divisions of the multi-division PD 38 is four (hereinafter, this is referred to as 4-division PD 38 '). As shown in FIG. 10, in this case, similarly to the two divisions, the four division PD 38 'is divided into four light receiving regions 38d, 38e, 38f, and 38g and placed in parallel on the substrate 38c. In the 4-split PD 38 ′, the imaging pattern light reflected by the sleeping person 2 and imaged by the light receiving lens 37 a forms an image on the 4-split PD 38 ′, thereby generating a current in each light receiving area.
[0054]
As shown in FIG. 11, an IV conversion amplifier 39d is connected to each of the light receiving regions 38d, 38e, 38f, and 38g. The current value of the current generated in each light receiving region is converted into a voltage value by the IV conversion amplifier 39d and input to the comparison circuit 39c. The comparison circuit 39c calculates the image formation position information, that is, the distance of the image formation pattern by comparing these. In the comparison by the comparison circuit 39c, it is preferable to calculate the imaging position information of the imaging pattern by taking the ratio of the two light receiving areas with large outputs among the light receiving areas 38d, 38e, 38f, and 38g. .
[0055]
The number of divisions of the light receiving surface 38 is preferably 10 divisions or less. Preferably it is 4 divisions or less, most preferably 2 divisions. By limiting the number of divisions, a simple structure can be achieved without increasing the number of attached devices such as the IV conversion amplifier 39d.
[0056]
Also, as shown in FIG. 10, when a multi-segment PD 38 having a larger number of divisions than two divisions is used, the imaging pattern moves greatly and deviates from the two light receiving areas, that is, the distance of the object being measured. Even when the value changes greatly, the imaging position information of the imaging pattern can be calculated from the other two light receiving regions.
[0057]
Further, in the case of a multi-segment PD 38 having a larger number of divisions than two divisions, the width in the moving direction of the imaging pattern (the left-right direction in the figure) due to the change in the distance of one light receiving region is set to be smaller than the pattern diameter. Good. This is because an image forming pattern does not extend over at least two light receiving areas but enters one light receiving area, so that a situation in which the ratio of voltage values does not change even if the image forming pattern moves is prevented. It is to do. That is, by doing so, it is possible to eliminate the situation where the ratio of the voltage values does not change even if the imaging pattern moves, and the distance can be measured stably and accurately. In addition, a telecentric optical system may be used as the light receiving lens 37a. In this case, since the pattern diameter is constant even if the distance of the object changes, the voltage value ratio changes only by moving the imaging pattern, so that the calculation can be simplified. A telecentric optical system is a telescope optical system in which a diaphragm is placed at one of the focal points of an objective lens. Even when the two-segment PD 38 is used, the light receiving lens 37a may be configured using a telecentric optical system as described above.
Hereinafter, the case where the two-divided PD 38 is used will be described.
[0058]
Returning to FIG. 6, the infrared distance sensor 30a will be further described. The light receiving lens 37a is coated so as to transmit only light in the wavelength band of the irradiated light beam. Therefore, the position can be detected with little influence of disturbance light. In the above description, the light beam is a thin parallel light beam. However, it may be a substantially parallel light beam, and may be a light beam diffused or converged to some extent. In this case, the size of the image formation pattern on the two-divided PD 38 may be appropriate and may be sufficient to detect the image formation position information of the image formation pattern.
[0059]
Further, the infrared distance sensor 30a may be configured such that the wavelength of the beam light projected by the infrared light irradiation unit 31a is different for each sensor. In this case, the transmission wavelength band of the coating applied to the light receiving lens 37a is also set to the transmission wavelength band corresponding to the light beam to be projected. As a result, even when the adjacent beam lights described in FIG. 3B overlap, there is no influence of the beam light of the adjacent sensor, and it is not necessary to control not to irradiate simultaneously. Can be simplified. In addition, the infrared distance sensor 30a may include an electrical bandpass filter that causes the infrared LED 34a (light source) to blink at a constant frequency and allows the infrared light receiving unit 32a to pass a signal of only that frequency. Thereby, the influence of disturbance light can be reduced. Further, by changing the modulation frequency for each sensor, even when the light beams described with reference to FIG. 3B overlap, it is not affected by the light beams of the adjacent sensors. As a result, even if the light beams overlap, it is not necessary to control so that they are not irradiated simultaneously, and the monitoring device can be simplified. Furthermore, it is also preferable to perform synchronous detection in which the polarity of the amplifier of the infrared light receiving unit 32a is switched in synchronization with the irradiation timing of the infrared LED 34a.
[0060]
The infrared distance sensor 30a is not visible to humans and does not give unpleasant feeling by using infrared rays as the beam light to be irradiated. In addition, the infrared distance sensor 30a may be obtained by simply replacing the PSD portion of an infrared distance sensor 30b using a PSD described later with a two-part PD 38.
[0061]
Thus, since the infrared distance sensor 30a can simplify the circuit configuration by using the two-divided PD 38, the infrared distance sensor 30a can be an inexpensive and simple monitoring device. In particular, by configuring the number of divisions in two, the circuit configuration can be greatly simplified, so that a simple and inexpensive monitoring device can be obtained.
[0062]
The sensor control unit 33a of the infrared distance sensor 30a performs modulation in order to distinguish from disturbance light when detecting the imaging position information of the imaging pattern. The modulation is, for example, an operation in which light beam emission (irradiation) is repeatedly stopped periodically. In this case, the light emission of the beam light may be stopped, for example, by stopping the light emission of the light source, or by stopping the light shielding plate or the slit. Further, in addition to the above-mentioned modulation, the output of the beam light may be changed depending on the intensity of disturbance light. Then, the sensor control unit 33a calculates an output value obtained by subtracting the output value of the two-divided PD 38 when not irradiating the beam light from the output value of the two-divided PD 38 when irradiating the beam light. Further, in order to ensure reliability, the sensor control unit 33a performs such an operation a plurality of times, and uses the average output value as imaging position information (hereinafter referred to as a distance measurement signal) of the imaging pattern. The sensor control unit 33a outputs the distance measurement signal value x, which is the value of the distance measurement signal, to the control device 20 as a distance.
[0063]
As shown in the schematic diagram of FIG. 12, the distance value A to the target sleeping person 2 can be calculated by the following formula using triangulation based on the distance measurement signal value x.
A = f × w / (x−b) (1)
When f is a single lens, the light receiving lens 37a of the infrared light receiving unit 32a is a focal length of the lens. The distance (base line length) between the optical axes of the lenses 37a, b indicates a bias value depending on the arrangement of the light receiving elements of the PD 38. Further, the focal length here is the focal length of the combination lens when a commonly used combination lens is used. When calculating the distance value A as described above, the distance value A may be calculated by the control unit 21 of the control device 20.
[0064]
In the above description, the infrared distance sensor 30a outputs the distance measurement signal value x as the distance. However, the infrared distance sensor 30a may be configured to output the distance value A itself calculated by the above method as the distance.
[0065]
Next, an infrared distance sensor 30b using PSD will be described with reference to the block diagram of FIG. The infrared distance sensor 30b includes an infrared light irradiation unit 31b as a light irradiation unit that irradiates the sleeper 2 with a light beam, an infrared light receiving unit 32b, and a sensor control unit 33b that controls the entire infrared distance sensor 30b. ing. The sensor control unit 33b may be provided in the control unit 21 of the control device 20 (see FIG. 4).
[0066]
The infrared light irradiation unit 31b includes an infrared LED 34b and an irradiation lens 35b, and the infrared light beam emitted from the infrared LED 34b sleeps as a thin parallel light beam through the irradiation lens 35b. Person 2 is irradiated. The infrared light receiving unit 32b includes a light receiving lens 37b as an imaging optical system that forms an image of a light irradiation pattern generated on the sleeping person 2 by the infrared light irradiation unit 31b, and an imaging position by the light receiving lens 37b. It has a one-dimensional PSD 36 as a light receiving means which is disposed in the vicinity and receives the image forming pattern light by the image of the light irradiation pattern formed. Further, the infrared distance sensor 30b is configured to output the imaging position information of the imaging pattern corresponding to the distance to the sleeping person 2 based on the imaging position of the imaging pattern light imaged on the PSD 36. The position information output unit 39b as a position information output device is provided. The position information output unit 39b is provided in the sensor control unit 33b. Here, similarly to the infrared light irradiation unit 31a, the light beam is a beam light, and the light irradiation pattern by the light beam is a beam light spot. The imaging pattern will be described as an image of a beam light spot.
[0067]
The light receiving lens 37b is coated so as to transmit only light in the irradiated wavelength band. Therefore, the position can be detected with little influence of disturbance light. In the above description, the light beam is a thin parallel light beam. However, it may be a substantially parallel light beam, and may be a light beam diffused or converged to some extent. In this case, the size of the pattern light on the PSD 36, which will be described later, may be appropriate and may be sufficient to supplement the position of the center of gravity.
[0068]
The PSD 36 will be further described with reference to FIG. FIG. 14A is a schematic plan view, and FIG. 14B is a schematic front sectional view. As shown in FIG. 14A, the PSD 36 has a light receiving area larger than that of the image formation pattern, and a required distance measurement range in the moving direction of the image formation pattern due to a change in distance (left and right in the figure). The length is such that the image formation pattern does not protrude due to the movement of the image formation pattern.
[0069]
As shown in FIG. 14B, the PSD 36 includes a P-type layer 36a on the surface that receives the flat-plate silicon imaging pattern light, an N-type layer 36b on the surface opposite to the P-type layer 36a, and a P-type layer. The I layer 36c is located between the 36a and the N layer 36b. The image formation pattern formed on the PSD 36 is converted into photoelectric and is divided and output from the electrodes 36d attached to both ends of the P layer 36a as photocurrent.
[0070]
The infrared distance sensor 30b outputs the barycentric position of the imaging pattern as the imaging position information of the imaging pattern by calculating the output signal of the photocurrent output from both ends of the PSD 36 by the position information output unit 39b. Thus, the distance to the sleeping person 2 can be measured. Moreover, since the irradiated light beam is infrared, it is not visible to humans and does not cause discomfort.
[0071]
The sensor control unit 33b of the infrared distance sensor 30b performs modulation to distinguish from disturbance light when the PSD 36 detects the position of the center of gravity of the imaging pattern. The modulation is the same operation as the modulation described in the infrared distance sensor 30a. In order to ensure reliability, the sensor control unit 33b performs a modulation operation a plurality of times, and uses the average output value as a center-of-gravity supplement signal (hereinafter referred to as a distance measurement signal) that is image formation position information of the image formation pattern. The sensor control unit 33 outputs the distance measurement signal value x, which is the value of the distance measurement signal, to the control device 20 as a distance. Further, the distance value A to the target sleeping person 2 can be calculated using the trigonometric method based on the distance measurement signal value x in the same manner as the method described in FIG. Further, like the infrared distance sensor 30a, the infrared distance sensor 30b has been described with respect to the case where the distance measurement signal value x is output as the distance, but the distance value A itself may be output as the distance.
[0072]
Thus, since the infrared distance sensor 30b can be simply configured by using the PSD 36, it can be an inexpensive and simple monitoring device.
[0073]
The distance measurement signal value x output from each infrared distance sensor 30 is modulated as described above. However, the influence of ambient light still remains slightly and fluctuates. In order to absorb this variation, the distance measurement signal values x acquired in time series are averaged to obtain data at that time. This data may be an average value of the distance value A calculated from the distance measurement signal value x, or may be an average value of the height H2 or the depth L1 that is an average value of the height H1 calculated from the distance value A described later. A certain depth L2 may be used. There are various ways of averaging, but a predetermined time interval may be determined in advance, the data between them may be averaged, or the number to be averaged in advance and the moving average value calculated in time series But you can. In the former case, the number of data is small, and it is suitable for grasping a rough state. In the latter case, the number of data is slightly increased, but a fine behavior can be followed.
[0074]
As described above, the distance of the sleeping person 2 can be acquired by using any of the above-described distance sensors as the distance sensor 11 of the monitoring device 1. That is, the distance of the sleeping person 2 can be measured. Hereinafter, the infrared distance sensor 30 will be described as the distance sensor 11.
[0075]
Returning to FIG. 4, the monitoring device 1 will be further described. The control device 20 includes a control unit 21. The control unit 21 controls the entire monitoring device 1. The plurality of distance sensors 11 are connected to the control unit 21 and controlled. A storage unit 24 is connected to the control unit 21 and can store data such as calculated information. Further, the storage unit 24 includes a distance storage unit 25 that stores the distance output from the distance sensor 11 in time series. Here, the distance stored in the distance storage unit 25 in time series may be a distance at a past time point of the monitoring time point, and may be a distance acquired one frame earlier, for example.
[0076]
Further, an input device 27 for inputting information for operating the monitoring device 1 and an output device 28 for outputting a result processed by the monitoring device 1 are connected to the control unit 21. The input device 27 is, for example, a touch panel, a keyboard, or a mouse, and the output device 28 is, for example, a display or a printer. Although the input device 27 and the output device 28 are illustrated as being externally attached to the control device 20 in this figure, they may be built in. Further, the input device 27 may be, for example, a switch that can start and release monitoring, and the output device 28 may be, for example, an LED as an operation indicator. In this way, the monitoring device 1 can be simply configured.
[0077]
Furthermore, the monitoring device 1 includes an alarm device 40 as alarm means for issuing an alarm. The alarm device 40 is connected to the control unit 21. The alarm device 40 is configured to issue an alarm by receiving an alarm signal transmitted from the determination unit 23 described later. That is, the alarm device 40 is configured to issue an alarm when the determination unit 23 determines that the sleeping person 2 is in a dangerous state, for example. Further, the alarm device 40 may be configured to issue an alarm even when an abnormality such as a failure of the monitoring device 1 occurs. By doing so, it is possible to promptly notify a third party that the sleeping person 2 is in a dangerous state, and therefore it is possible to quickly cope with the dangerous state. That is, the monitoring device 1 can improve monitoring reliability. In this figure, the alarm device 40 is illustrated as being externally attached, but may be provided internally.
[0078]
In addition, the control device 20 may be configured to notify the outside that the alarm has been issued via the interface 29 when the alarm device 40 issues an alarm. The outside is, for example, a place where the monitoring device 1 is managed, and in the case of a private house, for example, a living room or a fire department. In addition, the notification is based on, for example, the intensity of light including voice, characters, symbols, room lighting, or vibration. The interface 29 has a function of connecting to a communication line such as a general telephone line, an ISDN line, a PHS line, or a mobile phone line. In a private house, reporting to another room such as a living room or another bedroom may be performed via wireless or power line communication. Furthermore, the control device 20 may be provided with a voice output function, and may notify the third party by voice that the sleeping person is in a dangerous state via the interface 29.
[0079]
The control device 20 includes a human sensor 41 as presence detection means for detecting a sleeping person 2 existing in or near the monitoring area 50. As the human sensor 41, for example, a pyroelectric sensor that can detect the presence of a human body using heat rays, an ultrasonic sensor that detects the presence using ultrasonic waves, a motion sensor using image processing, or the like can be used. The human sensor 41 is preferably a pyroelectric sensor. By using the pyroelectric sensor, the monitoring device 1 can be configured to be small and inexpensive. The human sensor 41 operates as a motion sensor that captures fluctuations in the detection level because the absolute value of the detection level is difficult to distinguish between environmental changes and changes due to the presence or absence of the sleeping person 2.
[0080]
The human sensor 41 is preferably installed in the housing 10. If it does in this way, installation work of monitoring device 1 will become easy. Further, the monitoring device 1 can be downsized. Further, the attachment position of the human sensor 41 is not limited to the above, and may be any position as long as it can detect the sleeping person 2 existing in or near the monitoring area 50.
[0081]
The monitoring apparatus 1 further includes a human sensor 41. For example, when the human sensor 41 cannot detect the presence of the sleeping person 2 in the monitoring area 50 or in the vicinity of the monitoring area 50, the monitoring apparatus 1 Power can be saved because the power can be turned off. In other words, that is, when necessary, the monitoring device 1 can be turned on to save power. Further, when the movement of the sleeping person 2 is not detected by the distance sensor 11, it helps to determine whether the sleeping person 2 is not present, is present, or is not moving.
[0082]
Similarly, the pressure sensor 43 may be installed as a device that detects whether or not the sleeping person 2 is present. The pressure sensor 43 is, for example, a load sensor or a pressure sensor. The pressure-sensitive sensor 43 is located on the bed 6 on the bed 6 on the upper body side of the bed 6 or the legs of the bed 6 on the upper body side (in the four corners of the rectangular bed 6). It is good to arrange at the position. In this case, by using the output from the pressure-sensitive sensor 43, for example, the reliability of determining whether the user is in bed or out of bed increases.
[0083]
Furthermore, in the control part 21, the calculating part 22 as a calculating device which calculates a distance related value based on the distance output from the distance sensor 11, and the shape change of the sleeping person 2 based on the calculated distance related value And a determination unit 23 as a determination device for determining the presence or absence of the.
[0084]
Here, the distance-related value calculated by the calculation unit 22 is a time change in distance or an absolute value of this time change. In the present embodiment, the distance-related value will be described in the case of the absolute value of the time change of the distance. The shape change of the sleeping person 2 is, for example, a continuous shape change. Furthermore, the continuous shape change is a periodic change. The periodic change is, for example, the sleep of the sleeping person 2.
[0085]
The time change is calculated based on the distance by obtaining the distance from the distance sensor 11 at regular time intervals, thereby obtaining a difference between the distance acquired at the past monitoring time and the distance acquired at the monitoring time. Thus, the distance change amount in the past predetermined period is obtained. In other words, by obtaining the difference between the distance acquired from the distance sensor 11 and the distance stored in the distance storage unit 25 in time series, the distance change amount in the past predetermined period is obtained. The calculation of the time change based on the distance means that the distance between the maximum distance value and the minimum distance value obtained in the past predetermined period by acquiring the distance from the distance sensor 11 at a constant time interval (Max). -Min) may be used to obtain a distance change amount within a predetermined period in the past. Here, the former is suitable for detecting a periodic change. The latter is suitable for determining whether the sleeping person 2 described later is breathing, moving, or getting up. Hereinafter, although the case of using the latter distance change amount will be described, the former distance change amount may be used, and further, both the former and latter distance change amounts may be used. In this case, each determination unit 23 selects and uses each distance change amount. It is not always necessary to use a difference in distance to detect a periodic change, and it is also possible to detect the change from a distance acquired in time series by means such as frequency analysis.
[0086]
Here, the time interval for acquiring the distance from the distance sensor 11 is, for example, about 0.1 to 3 seconds, and preferably about 0.1 to 0.5 seconds. However, when there is random noise over the acquired distance, it is effective to perform acquisition or averaging processing at shorter time intervals. Further, the predetermined period here is set to about 30 seconds, more preferably about 10 to 20 seconds, but may be set to a shorter time, for example, about 3 seconds. When the predetermined period is set longer, it is effective for the determination unit 23 described later to determine whether the sleeping person 2 is up. When the predetermined period is set to be short, it is effective for determining the body movement of the sleeping person 2 in the same manner.
[0087]
Further, the calculation unit 22 sets a first predetermined period and a second predetermined period that is shorter than the first predetermined period, and the distance change amount of the first predetermined period and the distance of the second predetermined period It is advisable to obtain both the amount of change. In this case, similarly to the above, the first predetermined period is set to about 30 seconds, more preferably about 10 to 20 seconds, and the second predetermined period is set to about 1 to 10 seconds, more preferably 3 to 6 seconds. Set to about seconds. By doing in this way, judgment by judgment part 23 can be performed more correctly. In the above description, the predetermined period is described as time, but it may be the number of acquired distances (for example, 10 frames). Further, the calculation of the time change is performed for each distance sensor 11. That is, a distance change amount is obtained for each distance sensor 11.
[0088]
The distance change amount obtained by calculating the time change based on the distance by the calculation unit 22 forms a waveform pattern by arranging in the time direction.
FIG. 15 shows an example of a waveform pattern formed by a time change. The figure shows a waveform pattern corresponding to the normal movement of the sleeping person 2, for example, the movement of landing, resting, turning over, resting, getting up, and getting out of bed from the left side in the figure. The figure shows the case where the predetermined period is set to about 15 seconds.
[0089]
In the above description, the distance-related value has been described as the time change of the distance, particularly the absolute value of this time change, but may be the distance itself from the reference position. In this case, calculating the distance-related value based on the distance means obtaining the distance from the reference position at regular time intervals. The obtained distances are arranged in the time direction. Here, the reference position is, for example, the upper surface of the bed 6, but may be set in advance as the position of the upper surface of the chest or abdomen of the sleeper 2 having a standard body shape. The reference position may be stored in the distance storage unit 25 as a distance from the distance sensor 11 to the reference position. In this way, it is possible to easily determine the rising by the determination unit 23 described later.
[0090]
In this way, the distance-related value forms a waveform pattern by the calculation by the calculation unit 22.
FIG. 16 shows an example of a waveform pattern formed by distance-related values. In this example, the reference position is set to the position of the upper surface of the chest of the sleeper 2 having a standard body shape. The figure shows a waveform pattern corresponding to the normal movement of the sleeper 2 as in FIG.
Hereinafter, with reference to FIG. 15 as appropriate, the distance-related value will be described in the case of a time change of the distance.
[0091]
Further, the calculation unit 22 may be configured to calculate a moving average value or a period average value of the distance acquired from the output of the distance sensor 11 in the past certain number of times or acquired in the past certain period. In this case, when calculating the time change of the distance by the calculation unit 22, the moving average value or the period average value of the calculated distance is handled in the same manner as the distance output from the distance sensor 11. . In other words, the calculation unit 22 calculates the time change of the distance based on the moving average value or the period average value. Further, the moving average value and the period average value may be calculated by the distance sensor 11. In other words, the distance sensor 11 may be configured to calculate a moving average value or a period average value of the measured distance and output the calculation result as a distance. By doing so, random noise and sudden noise caused by sunlight flickering through the window can be reduced, and erroneous determination of peak positions and zero cross positions (intersections where signs are reversed) can be reduced. .
[0092]
Further, the calculation unit 22 may be configured to input a distance within a predetermined range among the distances output from the distance sensor 11. This can be easily performed by, for example, a band pass filter or a low pass filter. In this way, for example, a first threshold Th described later_1xCan be set lower, and the determination unit 23 described below can more accurately determine whether or not the sleeping person 2 has a shape change.
[0093]
The determination unit 23 will be described. The determination unit 23 includes a first threshold Th_1x, First threshold Th_1xThe second threshold value Th which is a larger value_2x, Second threshold Th_2xThe third threshold value Th which is a larger value_3xIs set. First threshold Th_1xIs a value corresponding to a distance variation of about 0.1 to 3 mm, more preferably about 0.1 to 0.5 mm. Second threshold Th_2xIs a value corresponding to a distance variation of about 3 to 20 mm, more preferably about 5 to 10 mm. Third threshold Th_3xIs a value corresponding to a distance variation of about 300 to 700 mm, preferably about 400 to 600 mm, and more preferably about 450 to 550 mm. Each threshold value may be set differently for each target point 5, that is, for each distance sensor 11. By doing in this way, monitoring device 1 can set up each above-mentioned threshold appropriate for every distance sensor 11, and can improve judgment accuracy.
[0094]
Further, when the reference position is set as shown in FIG. 16, each threshold value is the first threshold value Th._1xIs a value corresponding to a distance of about 0.1 to 3 mm, more preferably about 0.1 to 0.5 mm from the reference position. Second threshold Th_2xIs a value corresponding to a distance of about 3 to 20 mm, more preferably about 5 to 10 mm from the reference position. Third threshold Th_3xIs a value corresponding to a distance of about 300 to 700 mm, preferably about 400 to 600 mm, more preferably about 450 to 550 mm from the reference position. In this case, the first threshold Th_1x, Second threshold Th_2xWith respect to, the reference position needs to be corrected depending on the position where the luminous flux is incident on the sleeping person 2, but the third threshold Th_3xIs always a fixed reference position (for example, the upper surface of the bed 6) and is very easy to use.
[0095]
The determination unit 23 determines that the time change of the distance is the first threshold Th._1xAbove, the second threshold Th_2xAt the following time, the sleeper 2 is configured to determine that the first shape change has occurred. In addition, the determination unit 23 determines that the time change of the distance is the second threshold Th._2xLarger, the third threshold Th_3xAt the following time, the sleeper 2 is determined to have a second shape change different from the first shape change. In the present embodiment, the first shape change is a small body movement including breathing, abnormal breathing, convulsions and the like of the sleeping person 2. This is, for example, the state 153 or 154 in FIG. In the present embodiment, the second shape change is a large body movement such as the sleeping person 2 turning over. This is, for example, the state 155 in FIG.
[0096]
Moreover, the determination part 23 is comprised so that it may be judged that there existed the 3rd shape change, when the periodic change of the time change of distance was detected. Further, this determination is preferably performed while the state in which it is determined that there is a first shape change continues. In the present embodiment, the third shape change is a breath including normal breathing of the sleeper 2 and abnormal breathing that periodically changes. This is, for example, the state 154 in FIG. In the example shown in FIG. 15, since the predetermined period is about 15 seconds, respiration does not appear as a periodic change.
[0097]
Further, it is preferable that the determination unit 23 is configured to evaluate the period and amplitude of the periodic change and determine that there is a third shape change. Evaluating the period and amplitude of the periodic change is, for example, examining the synchrony. That is, the determination unit 23 checks the synchronism between the periodic change and the specified change, and determines that there is a third shape change when the synchronization is synchronized. The prescribed change is a waveform pattern of normal breathing or abnormal breathing described later with reference to FIG. By doing in this way, the judgment precision of the sleeper 2 presence / absence of breathing can be improved, and the amount of calculation by the control unit 21 can be reduced.
[0098]
Examining synchrony means analyzing the period (frequency) of time variation of distance using fast Fourier transform operation etc., and peaking the spectrum of this period existing in the target period range (for example, the period range of respiration) Is to evaluate whether the sharpness is a certain level or more. The sharpness of the peak can be evaluated by the ratio of the period power of the time change of the distance to the sum or average value of the power of each spectrum within the target period range.
[0099]
The determination unit 23 is configured to monitor the period of the periodic change based on the detected periodic change. Monitoring the period of the periodic change is, for example, monitoring the respiratory rate per unit time of the sleeping person 2.
[0100]
The determination unit 23 determines that the time change of the distance is the third threshold Th._3xWhen it exceeds, the sleeper 2 is configured to determine that the fourth shape change has occurred. In the present embodiment, the fourth shape change is a movement of the sleeping person 2 that is larger than the second shape change, for example, a movement such as getting up. For example, in FIG.
[0101]
Further, the determination unit 23 determines that the time change of the distance is the third threshold Th._3xWhen the change in shape of the sleeping person 2 cannot be detected within the first predetermined time after exceeding the predetermined time, it is determined that the sleeping person 2 has gone out of the monitoring area 50. This is the case, for example, when the state on the right side in FIG. The first predetermined time is, for example, about 10 to 60 seconds. At this time, after shifting from the state of 152 to the state of 151, the human sensor 41 detects the existence of the sleeping person 2 for a certain period of time, and when the existence of the sleeping person 2 cannot be detected thereafter, the sleeping person 2 You may make it judge that it went out of. As described above, the determination unit 23 may make a determination in combination with the detection of the presence or absence of the sleeping person 2 by the human sensor 41.
[0102]
Further, the determination unit 23 determines that the time change of the distance is the third threshold Th._3xOver time, the time variation of the distance obtained from the distance sensor 11 corresponding to the target points 51a, 51b, 51c, 54a, 54b, 54c (see FIG. 3) on the outer periphery of the bed 6 When the change is larger than the time change of the distance obtained from the distance sensor 11 corresponding to the target points 52a, 52b, 52c, 53a, 53b, 53c (see FIG. 3), the sleeper 2 is outside the monitoring area 50. You may make it judge that it came out. In this way, it is possible to determine getting out of bed regardless of time, for example. This is because when the sleeper 2 gets out of the bed, basically the movement of the outer periphery of the bed 6 is larger than that of the central portion. In addition, by doing in this way, it is possible to determine whether to get out of bed even when it takes a relatively long time when the sleeper 2 leaves the bed 6.
[0103]
The determination unit 23 is configured to determine that the sleeping person 2 is in the monitoring area 50 when the state in which the sleeping person 2 is determined to have a shape change continues for the second predetermined time. That is, it is determined that the sleeping person 2 is in the bed 6. This is the case, for example, when the state of 151 on the left side in FIG. 15 is shifted to any of 152, 153, 154, and 155 and this state continues for a second predetermined time. The second predetermined time is, for example, about 30 seconds to 60 seconds. The continuing state may be one of the above, or a plurality of states may occur sequentially.
[0104]
In addition, the determination of getting out of bed or bed presence by the determination unit 23 may be based on detection of the presence of the sleeping person 2 by the human sensor 41. This is the state 156 in FIG.
[0105]
The determination unit 23 determines that the time change of the distance is the first threshold Th._1xWhen the sleeper 2 is smaller, the sleeper 2 is determined to have no shape change, and after determining that the sleeper 2 is in the monitoring area 50, the state in which it is determined that there is no further shape change continues for a third predetermined time. Then, the sleeper 2 is determined to be in a dangerous state. In the present embodiment, the first threshold Th_1xIs set to remove signal noise.
[0106]
This is because the state in which it is determined that there is no change in shape despite the fact that the sleeper 2 has not left the bed has continued, for example, the sleep of the sleeper 2 has stopped, or This is because it can be estimated that the sleeper 2 has fallen from the bed 6. Further, in FIG. 15, for example, the state is changed from the state 154 to the state 151 without passing through the state 152. Further, the reason for continuing for the third predetermined time is that breathing may stop for a short time even when the sleeping person 2 is normal. The third predetermined time is, for example, about 60 seconds.
[0107]
The determination unit 23 is configured to determine that the sleeper 2 is in a dangerous state when the state in which it is determined that there is a second shape change continues for a fourth predetermined time. This is because when the large body movement of the sleeping person 2 continues for a short period of time, it can be assumed that the sleeping person 2 suffers for some reason and is rampant. FIG. 15 shows a case where the state 155 continues for a fourth predetermined time. This determination is for issuing an alarm when, for example, the sleeper 2 is suffering and is rampant. The fourth predetermined time is, for example, about 60 seconds.
[0108]
When the determination unit 23 determines that there is no shape change after determining that there is a second shape change at the target points 51a, 51b, 51c, 54a, 54b, 54c (see FIG. 3) on the outer peripheral portion of the bed 6 The sleeper 2 may be determined to have fallen from the bed 6.
[0109]
The determination unit 23 may be configured to determine that the sleeper 2 is in a dangerous state when it is determined that the sleeper 2 has moved out of the monitoring area 50. That is, it is configured to determine that it is a dangerous state when it is determined that the sleeper 2 has left the bed. This is because, when the monitoring device 1 is installed, for example, in a hospital or a nursing facility, it is determined whether the sleeping person 2 who needs to rest is free from bed or a trap. In addition, when the monitoring device 1 is installed in a private house (general household) and the above determination is unnecessary, the determination by the determination unit 23 may not be performed.
[0110]
The determination unit 23 may determine that the sleeper 2 is in a dangerous state when the respiratory rate of the sleeper 2 is not within a specified range. The specified range here is, for example, about 10 to 25 per minute.
[0111]
Further, when the determination unit 23 determines that the sleeper 2 has breathed, for example, when the period of the waveform pattern is disturbed in a short time, or when the period of the waveform pattern changes abruptly, It may be determined that the person 2 is in a dangerous state. This is because it can be presumed that the disease is, for example, lung disease such as spontaneous pneumothorax, bronchial asthma, heart disease such as congestive heart failure, or cerebrovascular disease such as cerebral hemorrhage.
[0112]
Further, the determination unit 23 is configured to transmit an alarm signal to the alarm device 40 when it is determined that the sleeper 2 is in a dangerous state.
[0113]
The determination of the presence or absence of the shape change of the sleeping person 2 by the determination unit 23 described above may be made by comprehensively determining the presence or absence of the shape change from the time change of the distance corresponding to each of the plurality of distance sensors 11. Although it is preferable, for example, when it is not particularly necessary to specify the target point 5, one distance sensor 11 is selected from the plurality of distance sensors 11, and the presence / absence of the shape change is determined based on the time change of the distance. You may go.
[0114]
When one distance sensor 11 is selected from among the plurality of distance sensors 11, for example, the distance sensor 11 having the largest time variation of the distance in the past fixed time is selected from the plurality of distance sensors 11. The presence or absence of the shape change of the sleeping person 2 may be determined based on the time change of the distance corresponding to the selected distance sensor 11. In this case, as a method for selecting the distance sensor 11, the distance sensor 11 having the largest variation in the time variation of the distance during the past several respiratory cycles (several seconds to about 10 to several seconds) of the sleeping person 2 is selected. The method is effective. This is because the shape change of the sleeping person 2 reflected in the time change of the distance corresponding to the target point 5 differs depending on the position of the target point 5 corresponding to each of the plurality of distance sensors 11. For this reason, in order to detect a minute change such as the third shape change (respiration), the determination unit 23 selects the distance sensor 11 corresponding to the time change of the distance accurately reflecting the change. This is because it is effective.
[0115]
One or more distance sensors 11 having a large time change are selected, frequency analysis is performed for each selected distance sensor 11, and the time change of the distance sensor 11 in which the peak of the frequency spectrum is the clearest is selected. May be.
[0116]
The distance sensor 11 selected in this way may change due to the second shape change of the sleeping person 2, for example, by turning over and moving, but in such a case, after being in a resting state. In about several seconds, the distance sensor 11 having the largest variation in the time variation of the distance is selected again, and for example, the sleep of the sleeping person 2 is detected. In this case, one cycle of the waveform pattern formed by the time change of the distance corresponds to one breath. In addition, you may use the sum total of all the time changes corresponding to the distance acquired from all the distance sensors 11 for the detection of respiration. In this case, since those with different phases are also added, the change may be canceled out. However, it is preferable to adopt the one having the larger change compared to the above-described maximum time change. Alternatively, the frequency spectrum may be compared and the one with a clear peak may be employed.
[0117]
Furthermore, the determination part 23 can also determine whether the sleeper 2 is moving from the time change of each distance corresponding to the plurality of distance sensors 11. In this case, the determination is made from the transition of the time change of the distance of each target point 5. For example, after the time change of the distance greatly fluctuates at the target points 51a, 51b, 51c (see FIG. 3) in the outer peripheral portion, the time change of the distance becomes large at the target points 52a, 52b, 52c (see FIG. 3) in the central portion. When it fluctuates, it can be determined that the sleeper 2 is moving from the outer peripheral portion of the bed 6 to the central portion. Furthermore, it is also possible to calculate the moving speed from the time difference of fluctuation as described above.
[0118]
With reference to FIG. 17, examples of normal and abnormal respiration waveform patterns will be described. The waveform pattern of normal breathing is a waveform pattern such as a sine curve (sin) as shown in FIG. Abnormal respiration waveform patterns are, for example, when there is a physiological disorder in the body, such as Cheyne-Stokes breathing, central hyperventilation, ataxic breathing, or Kussmul's breathing. It is a waveform pattern of respiration that is thought to occur. The abnormal respiration waveform pattern given above is an example, and the present invention is not limited to this.
[0119]
Further, the monitoring device 1 may include a respiration pattern storage unit 26 that stores the normal respiration waveform pattern and the abnormal respiration waveform pattern of the sleeper 2 as described above in the storage unit 24. In this way, it is possible to easily determine what waveform pattern the sleeping person 2 breaths belong to. Further, the breathing pattern storage unit 26 may store a waveform pattern in a state of spasm in the storage unit 24. If it does in this way, when it will be judged that the judgment part 23 had the 1st shape change, it can also detect that the sleeper 2 is having the convulsions.
[0120]
FIG. 17B shows a waveform pattern of Cheyne-Stokes respiration, FIG. 17C shows a waveform pattern of respiration of central hyperventilation, and FIG. 17D shows a waveform pattern of ataxic respiration.
Further, FIG. 18 shows a disease name or a disease location when the abnormal respiration waveform pattern is generated.
[0121]
The determining unit 23 uses the fact that the period (frequency), the number of appearances, and the depth of each respiration waveform pattern are different to determine which respiration waveform pattern belongs to which respiration waveform pattern. Determine. Further, the determination unit 23 determines that the sleeper 2 is in a dangerous state when it is determined that the time change of the distance belongs to the abnormal respiratory waveform pattern. The determination result may be output from the output device 28 by the control unit 21. The output contents are the detected respiratory rate and frequency of movement of the sleeper 2, the name of the abnormal breathing pattern, the disease name, the diseased organ, and the disease location that are considered to cause the breathing.
[0122]
In the above description, a plurality of distance sensors 11 have been described. However, a single distance sensor 11 may be used. In this case, the monitoring device 1 can be simplified and downsized. The monitoring device 1 can perform high-speed processing because the number of outputs from the distance sensor 11 to be processed decreases.
[0123]
In addition to the distance sensor 11, the monitoring device 1 uses the pressure sensor 43 (see FIG. 4) in combination, and uses the output from the pressure sensor 43, for example, to determine whether the user is in bed or out of bed. Increased reliability.
[0124]
According to the present embodiment as described above, it is possible not only to reliably detect the breathing of the sleeping person 2 but also to determine changes in the sleeping person 2 such as staying in bed, getting out of bed, and stopping breathing. Moreover, since image processing using a camera is not used, there is no psychological discomfort and high-speed processing is possible with a simple device. Furthermore, when it is determined that the sleeper 2 is in a dangerous state, an alarm is issued, so that a quick emergency response is possible. This is very advantageous when the monitoring device 1 is used for elderly people or sick people.
[0125]
【The invention's effect】
As described above, according to the present invention, a sensor that detects a variable having a correlation with a distance to a monitoring target in a monitoring target region, and a distance related value is calculated based on the variable output from the sensor. A computing device; and a judging device for judging the presence or absence of a shape change of the monitored object based on the computed distance-related value, wherein the judging device has the distance-related value equal to or greater than a first threshold value. The monitoring object is configured to determine that the first shape change has occurred when the monitoring object is equal to or less than a second threshold value that is greater than the first threshold value. When the monitoring object has a second shape change different from the first shape change when the value is less than a third threshold value that is greater than the second threshold value and greater than the second threshold value, It is configured to The change in the user not only can accurately detect, it is possible to provide a simple monitoring system.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view showing an outline of a monitoring apparatus according to an embodiment of the present invention.
FIG. 2 is a schematic perspective view for explaining a case where a housing portion of the monitoring device of FIG. 1 is installed on a stand.
FIG. 3 is a schematic plan view for explaining an arrangement example (a) of target points and an arrangement example (b) in which the target points overlap according to an embodiment of the present invention.
FIG. 4 is a block diagram illustrating a configuration example of a monitoring device used in the embodiment of the present invention.
FIG. 5 is a schematic side view illustrating a case where the distance sensor according to the embodiment of the present invention is installed with a curve.
FIG. 6 is a block diagram showing a configuration example of an infrared distance sensor using a two-segment PD used in the embodiment of the present invention.
FIG. 7 is a schematic diagram for explaining a case where two PDs are used in the case of FIG.
FIG. 8 is a conceptual diagram illustrating a case where two PDs are used in the case of FIG.
FIG. 9 is a diagram illustrating an example of a relationship between an area ratio and an object distance when an infrared distance sensor using a two-part PD used in the embodiment of the present invention is used.
FIG. 10 is a schematic diagram for explaining a quadrant PD used in an embodiment of the present invention.
FIG. 11 is a conceptual diagram for explaining a quadrant PD in the case of FIG. 10;
FIG. 12 is a schematic diagram for explaining a method for calculating the distance of the monitoring object in the embodiment of the present invention.
FIG. 13 is a block diagram showing a configuration example of an infrared distance sensor using a PSD used in the embodiment of the present invention.
14A is a schematic plan view for explaining PSD in the case of FIG. 13, and FIG. 14B is a schematic front sectional view thereof.
FIG. 15 is a diagram showing an example of a time-varying waveform pattern used in the embodiment of the present invention.
FIG. 16 is a diagram showing an example of a waveform pattern of a distance displacement amount from a reference position used in the embodiment of the present invention.
FIG. 17 is a schematic diagram showing normal and abnormal respiratory waveform patterns used in the embodiment of the present invention.
FIG. 18 is a diagram showing a table of disease names or disease locations corresponding to abnormal respiration waveform patterns in the case of FIG. 17;
[Explanation of symbols]
1 Monitoring device
2 Sleeper
3 Bedding
4 Ceiling
5 Target points
6 beds
7 Stand
10 housing
11 Distance sensor
20 Control device
21 Control unit
22 Calculation unit
23 Judgment Department
24 storage unit
25 Distance preservation part
26 breathing pattern storage
27 Input device
28 Output device
29 interface
30 Infrared distance sensor
30a Infrared distance sensor using two-part PD
Infrared distance sensor using 30b PSD
31a, 31b Infrared light irradiation part
32a, 32b infrared light receiver
33a, 33b Sensor control unit
36 PSD (position detection element)
37a, 37b Light receiving lens
38 Two-segment PD (photo detector)
40 Alarm device
41 Human sensor
50 Monitoring area

Claims (15)

A sensor for detecting a variable having a correlation with the distance to the monitoring object in the monitoring area;
An arithmetic unit that calculates a distance-related value based on the variable output from the sensor;
A determination device that determines presence or absence of a shape change of the monitoring object based on the calculated distance-related value;
The determination device is configured to determine that the monitoring object has a periodic shape change when a periodic change in the distance-related value is detected;
When the distance-related value is greater than or equal to a first threshold and less than or equal to a second threshold that is greater than the first threshold, the determination device has a first shape change in the monitored object. Configured to determine that;
When the distance-related value is greater than the second threshold and less than or equal to a third threshold that is greater than the second threshold, the determination device determines that the first shape change of the monitoring target is Configured to determine that there was a different second shape change;
Monitoring device. The monitored object is a sleeping person, and the periodic shape change is based on the sleeping person's breath;
The monitoring device according to claim 1. A breathing pattern storage unit for storing a waveform pattern of normal breathing and a waveform pattern of abnormal breathing of the sleeper;
The determination device is configured to collate a detected periodic change of the distance-related value with a respiration pattern stored in the respiration pattern storage unit to determine a pattern of the respiration waveform;
The monitoring device according to claim 2. When the distance-related value exceeds the third threshold and the determination device cannot detect a change in the shape of the monitoring target within a first predetermined time, the determination target is the monitoring target region. Configured to determine that they have gone out;
The monitoring apparatus according to any one of claims 1 to 3. The determination device is configured to determine that the monitoring object has a fourth shape change when the distance-related value exceeds the third threshold;
The monitoring apparatus according to any one of claims 1 to 4. The determination device is configured to determine that the monitoring target is within the monitoring target area when a state where it is determined that there is a change in the shape of the monitoring target continues for a second predetermined time;
The monitoring device according to any one of claims 1 to 5. The determination device is configured to determine that there is no shape change in the monitoring target when the distance-related value is smaller than the first threshold, and determines that the monitoring target is in the monitoring target area. The monitoring object is further determined to be in a dangerous state when the state in which it is determined that there is no change in shape continues for a third predetermined period of time;
The monitoring device according to claim 6. The determination device is configured to determine that the monitoring object is in a dangerous state when the state in which the second shape change is determined continues for a fourth predetermined time;
The monitoring device according to any one of claims 1 to 7. Providing alarm means for issuing an alarm;
The determination device is configured to transmit an alarm signal to the alarm means when determining that the monitored object is in a dangerous state;
The monitoring device according to claim 7 or 8. The calculated distance-related value is a time change of the variable or an absolute value of the time change;
The monitoring apparatus according to any one of claims 1 to 9. The sensor includes a light irradiation unit that irradiates the monitoring object with a light beam, an imaging optical system that forms an image of a light irradiation pattern generated on the monitoring object by the light irradiation unit, and the imaging A light receiving surface that is disposed in the vicinity of an image formation position by the optical system and that receives the image formation pattern light by the image of the imaged light irradiation pattern;
Further, it receives a signal from each of the light receiving areas, compares the intensity of the imaging pattern light incident on each of the light receiving areas based on the received signal, and forms an image corresponding to the distance to the monitoring object. A position information output device configured to output imaging position information of the pattern;
The monitoring apparatus according to any one of claims 1 to 10. The sensor includes a light irradiation unit that irradiates the monitoring object with a light beam, an imaging optical system that forms an image of a light irradiation pattern generated on the monitoring object by the light irradiation unit, and the imaging A light receiving means that is disposed in the vicinity of an image forming position by the optical system and receives the image forming pattern light by the image of the imaged light irradiation pattern;
Position information output configured to output the imaging position information of the imaging pattern corresponding to the distance to the monitoring object based on the imaging position of the imaging pattern light imaged on the light receiving means. Comprising a device;
The monitoring apparatus according to any one of claims 1 to 10. A sensor for detecting a variable having a correlation with the distance to the monitoring object in the monitoring area;
An arithmetic unit that calculates a distance-related value based on the variable output from the sensor;
A determination device that determines presence or absence of a shape change of the monitoring object based on the calculated distance-related value;
The determination device is configured to determine that the monitoring object has a periodic shape change when a periodic change in the distance-related value is detected;
The monitored object is a sleeping person, and the periodic shape change is based on the sleeping person's breathing;
A breathing pattern storage unit for storing a waveform pattern of normal breathing and a waveform pattern of abnormal breathing of the sleeper;
The determination device is configured to collate a detected periodic change of the distance-related value with a respiration pattern stored in the respiration pattern storage unit to determine a pattern of the respiration waveform;
The determination device is configured to determine that the monitored object is in a dangerous state when the determined respiration waveform pattern is the abnormal respiration waveform pattern;
Monitoring device. Providing alarm means for issuing an alarm;
The determination device is configured to transmit an alarm signal to the alarm means when determining that the monitored object is in a dangerous state;
The monitoring device according to claim 13 . A plurality of the sensors are provided;
The monitoring device according to any one of claims 1 to 14 .

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