JP4365699B2 - Condition analysis device - Google Patents

Description

  The present invention relates to a state analysis apparatus, and more particularly to a state analysis apparatus that can accurately grasp an abnormality in the state of an object.

2. Description of the Related Art Conventionally, a motion detection sensor has been proposed as a motion detection device that detects a motion of an object in a space, for example, a bathroom or a toilet, for example, a person. As a typical example, there is a monitoring device that monitors a sleeper's breathing by calculating a pattern movement amount from an image obtained by continuously projecting the projected pattern onto a sleeper on the bed. (For example, see Patent Document 1).
JP 2002-175582 A (page 5-9, FIG. 1-13)

  However, according to the conventional apparatus as described above, it is difficult to accurately grasp the state of each part of the object, for example, the direction of movement of the part having movement and the state of movement. Furthermore, for example, abnormalities that do not appear in the average motion magnitude of the upper body were difficult to detect.

  Accordingly, an object of the present invention is to provide a state analysis apparatus that can accurately grasp an abnormality in the state of an object.

In order to achieve the above object, the state analysis apparatus 1 according to the first aspect of the present invention, as shown in FIGS. 1 and 4, for example, measures a plurality of movements in the height direction of the target object 2 existing in the target region. A three-dimensional sensor 10 that measures points; and a calculation means 20 that calculates information indicating the state of the object 2 based on the plurality of measured movements; the calculation means 20 includes a plurality of measurement points. and among the weighting without representative position calculation means 22 for calculating a weighting no representative coordinates of the position coordinates in the region a measurement point motion form, wherein at the measurement point for each of the position coordinates of the measuring points for which the said motion based on the value obtained by weighting an amount related to the amount of motion, a weighting center-of-gravity position calculating means 23 for calculating the weighted center coordinates of the area measurement points were Oh Tsu of the motion forms, Mu said weighting If the difference between the weighted center coordinates and representative coordinates is larger than the threshold value, and a data output unit 24 for outputting the warning data. It should be noted that the unweighted representative position calculation means 22 may perform a calculation using the average value of all the position coordinates of the measurement point that has moved as the unweighted representative coordinates.

  If comprised in this way, the state of the target object 2 based on the three-dimensional sensor 10 which measures the motion of the height direction of the target object 2 existing in the target region at a plurality of measurement points, and the measured plurality of movements. Therefore, the calculation means 20 can calculate information indicating the state of the object 2 based on a plurality of movements measured by the three-dimensional sensor 10. Further, since the calculation means 20 includes the unweighted representative position calculation means 22, the weighted centroid position calculation means 23, and the data output means 24, the unweighted representative coordinates of the position coordinates of the plurality of measurement points, Based on a value weighted by an amount related to the amount of movement of the plurality of measurement points, a weighted centroid coordinate of an area formed by the measurement point with movement can be calculated, and the unweighted representative coordinate and the weighted centroid coordinate Since the warning data is output when the difference between and becomes larger than the threshold value, the state analysis apparatus 1 that can accurately grasp the abnormality of the state of the object can be provided.

  Further, as described in claim 2, in the state analysis device 1 according to claim 1, the unweighted representative position calculation means 22 and the weighted centroid position calculation means 23 are only coordinates in the one-dimensional direction of the plurality of measurement points. It is preferable to calculate the unweighted representative coordinates and the weighted barycentric coordinates by using.

  Further, as described in claim 3, in the state analyzing apparatus 1 according to claim 1 or 2, as shown in FIG. 2, for example, the three-dimensional sensor 10 projects the pattern light onto the target region. 11; an imaging device 12 that images the target area onto which the pattern light is projected; and a measuring unit 14 that measures the movement of the pattern on the captured image; based on the movement of the measured pattern Thus, the movement of the object 2 in the height direction may be measured at a plurality of points.

  If comprised in this way, it has the projection apparatus 11, the imaging device 12, and the measurement means 14, images the object area | region where the pattern light was projected, and measures the movement of the pattern on the said imaged image Further, since the movement in the height direction of the object 2 is measured at a plurality of points based on the movement of the measured pattern, the height direction of the object 2 can be accurately measured with a simple configuration. Can be measured at multiple points.

  Further, as described in claim 4, in the state analysis device 1 according to any one of claims 1 to 3, the measurement point where the amount of movement measured by the three-dimensional sensor 10 is less than or equal to the threshold value is It is good not to use for the calculation by the calculating means 20.

  Further, as described in claim 5, in the state analysis device 1 according to any one of claims 1 to 4, the measurement point where the frequency of motion measured by the three-dimensional sensor 10 is equal to or greater than a threshold value is , The calculation means 20 may not be used for calculation.

  As described above, according to the present invention, a three-dimensional sensor that measures a movement in the height direction of an object existing in a target area at a plurality of measurement points, and the object based on the plurality of measured movements. Computing means for computing information indicating the state of an object, the computing means comprising: an unweighted representative position computing means for computing unweighted representative coordinates of the position coordinates of the plurality of measurement points; and a plurality of measurement points. Weighted centroid position calculating means for calculating weighted centroid coordinates of an area formed by the measurement point with movement based on a value weighted by an amount related to the amount of movement, the unweighted representative coordinates, and the weighted centroid coordinates When the difference between the two becomes larger than the threshold value, it has a data output means for outputting warning data, so that it is possible to provide a state analysis device that can accurately grasp the abnormality of the state of the object.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, in each figure, the same code | symbol is attached | subjected to the mutually same or equivalent member, and the overlapping description is abbreviate | omitted.

  FIG. 1 is a schematic external view of a monitoring device 1 as a state analysis device according to an embodiment of the present invention. The monitoring device 1 measures the height movement of an object existing in the target area at a plurality of measurement points, and based on the plurality of movements measured by the three-dimensional sensor 10, And an arithmetic unit 20 as arithmetic means for calculating information indicating the state. The arithmetic device 20 also controls the monitoring device 1. The monitoring device 1 is configured to monitor the target area. In the present embodiment, the object breathes. That is, the object is, for example, a person or an animal. In the present embodiment, the object is described as a person 2. The movement of the object in the height direction is a movement caused by breathing. That is, the movement in the height direction is a movement of the person 2 due to breathing. In the present embodiment, the target area is on the bed 3. Furthermore, the target area is an area captured on the bed 3 by an imaging device 12 (see FIG. 2) described later. The three-dimensional sensor 10 can also measure the height at each measurement point in the target area.

  In addition, the person 2 lies on the bed 3 in the figure. In addition, a bedding 4 is hung on the person 2 and covers a part of the person 2 and a part of the bed 3. In this case, the three-dimensional sensor 10 measures the movement of the upper surface of the bedding 4 in the height direction. When the bedding 4 is not used, the three-dimensional sensor 10 measures the movement of the person 2 in the height direction.

  A three-dimensional sensor 10 is disposed on the upper portion of the bed 3. The three-dimensional sensor 10 will be described in detail later. In the drawing, the three-dimensional sensor 10 and the arithmetic unit 20 are shown as separate bodies, but may be configured integrally. If it does in this way, the monitoring apparatus 1 can be reduced in size. The computing device 20 is typically a computer such as a personal computer.

  The three-dimensional sensor 10 will be described with reference to the schematic external view of FIG. In the present embodiment, the three-dimensional sensor 10 measures the movement of the person 2 in the height direction using a triangulation method. Here, a case where an FG sensor is used will be described. The FG sensor will be described in detail later. Hereinafter, the three-dimensional sensor 10 will be described as the FG sensor 10. The FG sensor 10 includes a projection device 11 that projects pattern light onto a target region, that is, a bed 3, an imaging device 12 that images the bed 3 onto which the pattern light is projected, and a pattern on an image captured by the imaging device 12. And a measuring device 14 as a measuring means for measuring the movement of. Further, the measuring device 14 is configured to measure the movement of the person 2 in the height direction at a plurality of points based on the measured movement of the pattern. The projection device 11 and the imaging device 12 are electrically connected to the measurement device 14 and controlled by the measurement device 14. The imaging device 12 is typically a CCD camera. In the present embodiment, the measuring device 14 is configured integrally with the arithmetic device 20.

  Here, the projected pattern light is a plurality of bright spots. The plurality of bright spots projected on the bed 3 correspond to the plurality of measurement points on the bed 3, respectively. That is, the plurality of measurement points correspond to the bright points projected on the person 2 existing on the bed 3. Furthermore, the plurality of measurement points correspond to the bright spots existing within the angle of view of the image captured by the imaging device 12 among the bright spots projected on the person 2. Further, the movement in the height direction of the person 2 measured at a plurality of points corresponds to the movement of the bright spot described later with reference to FIG. 6 (note that the amount of movement corresponds to the movement amount of the bright spot). Each configuration will be described below.

  With reference to the schematic perspective view of FIG. 3, the projection apparatus 11 suitable for the monitoring apparatus 1 is demonstrated. Here, for the sake of explanation, a case will be described where the target region is the plane 102 and a laser beam L1 described later is projected perpendicularly to the plane 102. The projection apparatus 11 includes a light beam generation unit 105 serving as a light beam generation unit that generates a coherent light beam, and a fiber grating 120 (hereinafter simply referred to as a grating 120). The coherent light beam projected by the light beam generation unit 105 is typically an infrared laser. The light beam generation unit 105 is configured to generate a parallel light beam. The light flux generation unit 105 is typically a semiconductor laser device including a collimator lens (not shown), and the generated parallel light flux is a laser light flux L1. The laser light beam L1 is a light beam having a substantially circular cross section. Here, the parallel light flux only needs to be substantially parallel, and includes a nearly parallel light flux.

  Further, here, the grating 120 is disposed in parallel to the plane 102 (perpendicular to the Z axis). Laser light L1 is incident on the grating 120 in the Z-axis direction. Then, the laser beam L1 is condensed in a plane having the lens effect by each optical fiber 121, and then spreads as a diverging wave, interferes, and interferes with a plurality of bright spot arrays on the plane 102 which is a projection plane. A pattern 11a is projected. Note that the arrangement of the grating 120 in parallel with the plane 102 means, for example, that the plane including the axis of each optical fiber 121 of the FG element 122 constituting the grating 120 and the plane 102 are parallel.

  The grating 120 includes two FG elements 122. In the present embodiment, the planes of the FG elements 122 are parallel to each other. Hereinafter, the plane of each FG element 122 is referred to as an element plane. In the present embodiment, the axes of the optical fibers 121 of the two FG elements 122 are substantially orthogonal to each other.

  The FG element 122 is configured by arranging, for example, several tens to several hundreds of optical fibers 121 having a diameter of several tens of microns and a length of about 10 mm in parallel in a sheet shape. Further, the two FG elements 122 may be arranged in contact with each other, or may be arranged at a distance from each other in the normal direction of the element plane. In this case, the distance between the two FG elements 122 is set so as not to interfere with the projection of the pattern 11a. The laser beam L1 is typically incident perpendicular to the element plane of the grating 122. Here, the grating 120 using the FG element 122 will be described. However, the present invention is not limited to this, and a grating using, for example, a diffraction grating or a microlens array may be used instead of the grating 120.

  Thus, since the grating 120 configured to include the two FG elements 122 serves as an optical system, the optical housing can be downsized without requiring a complicated optical system. Furthermore, by using the grating 120, the projection device 11 can project a plurality of bright spots 11b as a pattern 11a onto the target area with a simple configuration. The pattern 11a is typically a plurality of bright spots 11b arranged in a square lattice pattern. The bright spot has a substantially circular shape including an ellipse.

  Returning to FIG. The imaging device 12 includes an imaging optical system 12a (see FIG. 5) and an imaging element 15 (see FIG. 5). The image sensor 15 is typically a CCD image sensor. In addition to the CCD, an element having a CMOS structure has recently been actively announced as the image pickup element 15, and these can naturally be used. In particular, some of the elements themselves have inter-frame difference calculation and binarization functions, and it is preferable to use these elements.

  The imaging device 12 may include a filter 12b (see FIG. 5) that attenuates light having a wavelength other than the peripheral portion of the wavelength of the laser beam L1 generated by the above-described light beam generation unit 105 (see FIG. 3). The filter 12b is typically an optical filter such as an interference filter, and may be disposed on the optical axis of the imaging optical system 12a. In this way, the imaging device 12 can reduce the influence of disturbance light because the light intensity of the pattern 11a projected from the projection device 11 out of the light received by the imaging device 15 is relatively increased. The laser beam L1 generated by the beam generator 105 is typically an infrared laser beam. Further, the laser beam L1 may be irradiated continuously or intermittently. When irradiating intermittently, imaging by the imaging device 12 is performed in synchronization with the timing of irradiation.

  Here, an installation example of the FG sensor 10 will be described. The projection device 11 and the imaging device 12 are disposed above the bed 3. In the figure, the imaging device 12 is disposed approximately above the head of the person 2, and the projection device 11 is disposed approximately above the center of the bed 3. The projection device 11 projects a pattern 11 a on the bed 3. In addition, the angle of view of the imaging device 12 is set so that the center portion of the bed 3 can be imaged. More specifically, the angle of view is set so that the chest and abdomen of the person 2 present on the bed 3 can be imaged mainly. That is, the imaging device 12 mainly captures bright spots projected on the chest and abdomen of the person 2. In this way, it is easy to measure respiration with high accuracy by capturing the bright spots projected on the chest and abdomen, where the movement of respiration is easily reflected. The FG sensor 10 is installed so that the direction of the straight line connecting the projection device 11 and the imaging device 12, that is, the baseline direction of the triangulation method, is parallel to the center line in the longitudinal direction of the bed 3. Furthermore, in the FG sensor 10, the base line direction of the FG sensor 10 and the center line in the longitudinal direction of the bed 3 are parallel, and the base line connecting the projection device 11 and the imaging device 12 is the center line in the longitudinal direction of the bed 3. It is arrange | positioned so that it may be located in the vertical upper direction. Here, the base line direction is described as being parallel to the longitudinal center line of the bed 3, but may be, for example, a direction orthogonal to the longitudinal center line of the bed 3. Even in this case, there is no problem in measuring the movement of the person 2.

  Here, the projection device 11 has its optical axis (projection direction of the laser beam L1) installed in a direction substantially parallel to the vertical direction of the upper surface of the bed 3 as shown in the figure. Here, as described above, the projection device 11 has its optical axis installed in a direction substantially parallel to the vertical direction of the upper surface of the bed 3, but may be installed in an inclined manner with respect to the vertical direction. .

  Here, the imaging device 12 is installed with its optical axis inclined with respect to the vertical direction of the upper surface of the bed 3. By doing so, for example, it is possible to easily install the imaging device 12 and the projection device 11 at a distance. In other words, it is easy to increase the base length of the triangulation method. Here, as described above, the imaging device 12 is installed with its optical axis inclined with respect to the vertical direction of the upper surface of the bed 3. However, like the projection device 11, its optical axis is set on the upper surface of the bed 3. You may install in a parallel direction with respect to a perpendicular direction. Further, the projection device 11 and the imaging device 12 may be installed with their optical axes oriented in parallel to each other.

  Further, the projection device 11 and the imaging device 12 may be installed with a certain distance therebetween. By doing so, the distance d (base line length d), which will be described later with reference to FIG. 5, is increased, so that the change can be detected sensitively. The base line length is preferably long, but may be short. However, in this case, it is difficult to detect small movements such as respiration, but small movements (breathing) can be detected by detecting the barycentric position of the bright spot as described later.

  A configuration example of the monitoring device 1 will be described with reference to the block diagram of FIG. As described above, the arithmetic device 20 is configured integrally with the measuring device 14. Furthermore, the measuring device 14 is configured integrally with a control unit 21 described later. The projection device 11 and the imaging device 12 are electrically connected to the measurement device 14 and controlled as described above. In the present embodiment, the arithmetic device 20 is remotely arranged with respect to the projection device 11 and the imaging device 12. Specifically, for example, it is installed in the side of the bed 3 or in a room different from the room in which the bed 3 is installed, such as a nurse station.

  First, the measuring device 14 will be described. As described above, the measurement device 14 measures the movement of the pattern on the image picked up by the image pickup device 12, and further determines the movement of the person 2 in the height direction based on the movement of the measured pattern. Measure at multiple points. The measuring device 14 is configured to acquire an image captured by the imaging device 12. Further, the measuring device 14 is configured to measure the movement of each bright spot on the image picked up by the image pickup device 12. Here, the projected bright spot and the image of the bright spot on the captured image are simply referred to as bright spot for convenience. Here, measuring the movement of the bright spot means measuring the amount of movement of the bright spot (hereinafter referred to as the movement amount).

  Here, the measurement of the movement of the bright spot by the measuring device 14 will be described in detail. The measuring device 14 is configured to measure the movement of the bright spot based on two different time points acquired from the imaging device 12.

  Here, the measurement of the movement of the bright spot based on the images at two different time points will be described. The images at two different time points may be an arbitrary time point and a slightly previous time point. “Slightly before” only needs to be a time interval sufficient to detect the movement of the person 2. In this case, when a slight movement of the person 2 is desired to be detected, the time is short, for example, the movement of the person 2 does not become too large, and the time can be regarded as substantially no movement, for example, about 0.1 seconds. . Or it is good to set it as the 1-10 period (1 / 30-1 / 3) of a television period. Further, when it is desired to detect a rough movement of the person 2, it may be long, for example, about 10 seconds. However, in the case of detecting the respiration of the person 2 as in the present embodiment, if it is too long, accurate detection of respiration cannot be performed. Hereinafter, an image acquired at an arbitrary time (current) is described as an acquired image, and an image acquired slightly before (past) the acquired image is described as a reference image. The reference image is stored in the storage unit 31. In the present embodiment, the images at two different time points are an acquired image (N frame) and an image (N-1 frame) acquired immediately before the acquired image. That is, the reference image is an image acquired immediately before the acquired image. The image acquisition interval may be appropriately determined depending on, for example, the processing speed of the apparatus and the content of the motion to be detected as described above. For example, it is 0.1 to 3 seconds, preferably about 0.1 to 0.5 seconds. It is good to do. In addition, it is effective to acquire images at shorter time intervals and perform averaging or filtering to reduce the influence of random noise, for example.

  It should be noted that a waveform (for example, a sum of bright spot movement amounts) obtained by measuring bright spot movement based on an image at an arbitrary time point and two time points slightly different from the previous time point is a differential waveform of distance, The waveform represents the speed change. For example, when it is desired to obtain a waveform representing a change in height, if the waveform is integrated, a waveform of distance, that is, a waveform indicating a change in height is obtained.

  Here, the acquired image and the reference image are images picked up by the image pickup device 12, for example, and are concepts including the position information of the bright spot on each image. That is, the acquired image and the reference image are images of the pattern 11a formed by the projection of the projection device 11 at each time point. In the present embodiment, the reference image is stored in the storage unit 31 in the form of position information such as coordinates regarding the position of each bright spot, for example, not as a so-called image. Note that the coordinates here are set, for example, in an image captured by the imaging device 12. In this way, when measuring the movement amount of the bright spot, which will be described later, for example, it is only necessary to compare the coordinates and direction of the bright spot, so the processing becomes simple. Further, here, the position of the bright spot is the barycentric position of the bright spot. By doing in this way, the movement of a slight bright spot can also be measured.

  Further, as described above, the moving amount of the bright spot is obtained by comparing the position information of each bright spot on the reference image stored in the storage unit 31 with the position information of each bright spot on the acquired image. Measure the amount of bright spot movement. Each amount of movement can be obtained, for example, by counting the number of pixels to which the position of the bright spot has moved (how many pixels have moved). The measured moving amount of the bright spot is a concept including the moving direction of the bright spot. In other words, the measured moving amount of the bright spot includes information on the moving direction. In this way, as will be described later, it is not necessary to generate a difference image, so that the processing can be simplified.

  In the above description, the position information of the bright spots is compared. However, a difference image between the reference image and the acquired image may be created. In this case, the movement amount of the bright spot is measured based on the position of the corresponding bright spot from the difference image. In this way, since only the moved bright spot remains on the difference image, the processing amount can be reduced.

  Furthermore, the moving amount of the bright spot measured by the measuring device 14 may be a moving average value or a period average value of the moving amount of the bright spot that has been measured a certain number of times in the past or measured within the past fixed period. By doing so, it is possible to reduce random noise and sudden noise caused by sunlight flickering through a window, and the reliability of the measured moving amount of bright spots is improved.

  The measuring device 14 is configured to measure the movement of the bright spot as described above for each bright spot forming the pattern 11a. That is, the positions of a plurality of bright spots become a plurality of measurement points. The measuring device 14 outputs the bright spot movement measured for each bright spot forming the pattern 11a, that is, the measured bright spot movement amount to the control unit 21 as a measurement result. That is, the measurement result is the moving amount of the bright spot measured based on images at two different time points. As will be described later with reference to FIG. 5, this measurement result corresponds to the movement of the object 2 at each bright point (measurement point), here the person 2 in the height direction. Hereinafter, this measurement result is referred to as motion information. The measuring device 14 outputs the measurement result at each measurement point as motion information. Note that the movement of the person 2 in the height direction is, for example, movement accompanying the breathing of the person 2.

  Here, the concept of bright spot movement will be described with reference to the conceptual perspective view of FIG. Here, it is easy to understand, and the target area will be described as the plane 102 and the target object as the object 103. Further, here, for description, the reference image is an image of the pattern 11a when the object 103 is not present on the plane 102, and the acquired image is described as the pattern 11a when the object 103 is present on the plane 102. To do.

  In the figure, an object 103 is placed on the plane 102. Further, the orthogonal coordinate system XYZ is taken so that the XY axis is placed in the plane 102, and the object 103 is placed in the first quadrant of the XY coordinate system. On the other hand, a projection device 11 and an imaging device 12 are arranged above the plane 102 on the Z axis in the drawing. The imaging device 12 images the plane 102 on which the pattern 11 a is projected by the projection device 11. In other words, the object 103 placed on the plane 102 is imaged.

  Here, the imaging lens 12a as the imaging optical system of the imaging device 12 is disposed so that its optical axis coincides with the Z-axis. The imaging lens 12 a forms an image of the pattern 11 a on the plane 102 or the object 103 on the imaging surface 15 ′ (image plane) of the imaging device 15 of the imaging device 12. The image plane 15 'is typically a plane orthogonal to the Z axis. Further, an xy orthogonal coordinate system is taken in the image plane 15 'so that the Z axis passes through the origin of the xy coordinate system. The projection device 11 is arranged at a distance equal to the imaging lens 12a from the plane 102 and a distance d (baseline length d) from the imaging lens 12a in the negative direction of the Y axis. A pattern 11 a formed by a plurality of bright spots 11 b is projected onto the object 103 and the plane 102 by the projection device 11. The y-axis direction is also the baseline direction of the triangulation method.

  The pattern 11 a projected onto the plane 102 by the projection device 11 is blocked by the object 103 and does not reach the plane 102 in a portion where the object 103 exists. Here, if the object 103 exists, the bright spot 11 b to be projected onto the point 102 a on the plane 102 is projected onto the point 103 a on the object 103. Since the bright spot 11b has moved from the point 102a to the point 103a and the imaging lens 12a and the projection device 11 are separated by a distance d (baseline length d), the point 102a is formed on the imaging plane 15 ′. An image to be imaged at '(x, y) is imaged at a point 103a' (x, y + δ). That is, when the object 103 does not exist and when the object 103 exists, the image of the bright spot 11b moves by a distance δ in the y-axis direction.

  For example, as shown in FIG. 6, the bright spot imaged on the imaging surface 15 ′ of the image sensor 15 is moved in the y-axis direction by δ by the object 103 having a height.

  Thus, by measuring the movement amount δ of the bright spot, the position of the point 103a on the object 103 can be specified three-dimensionally. That is, for example, the height of the point 103a is known. In this way, by measuring the difference between a point that should be imaged on the imaging plane 15 ′ if the object 103 is not present and the actual imaging position on the imaging plane 15 ′, The height distribution of the object 103, in other words, the three-dimensional shape can be measured. Alternatively, the three-dimensional coordinates of the object 103 can be measured. Further, if the pitch of the pattern 11a, that is, the pitch of the bright spot 11b is made fine enough that the correspondence relationship of the bright spot 11b is not unknown, the height distribution of the object 103 can be measured in detail.

  Based on the above concept, the measuring device 14 can measure the height of the object by measuring the moving amount of the bright spot. However, here, since the movement in the height direction is measured based on the acquired image and the image acquired immediately before the acquired image, that is, the reference image, the amount of change in the movement of the bright spot is observed. For this reason, for example, the absolute height of the person 2 cannot be measured, but there is no problem because the purpose is to detect the movement of the person 2 in the height direction.

  Furthermore, the monitoring device 1 is configured such that a measurement point at which the amount of movement measured by the FG sensor 10 is less than or equal to a threshold value is not used for calculation by the calculation device 20. In the present embodiment, it is configured not to output data of a measurement point whose amount of movement measured by the measurement device 14 is equal to or less than a threshold value to the arithmetic device 20. The threshold is typically set smaller than the breathing movement of the person 2. Specifically, the movement is set to be smaller than the respiration of the person 2, more specifically, the movement amount of the bright spot corresponding to the small movement. This makes it possible to ignore measurement points at which movement smaller than respiration is measured. By doing in this way, the influence by noise can be effectively excluded, for example. The movement smaller than the movement of breathing means movement smaller than the range of movement in the height direction by breathing. As described above, since the movement amount of the bright spot indicates the change amount of the bright spot movement, in other words, the movement speed, the movement smaller than respiration is, for example, the movement speed in the height direction due to respiration. When the range is about 2 to 40 mm / s, it means a movement at a speed of 2 mm / s or less. That is, in this case, the threshold value is preferably set to 2 mm / s. In other words, the moving amount of the bright spot corresponding to the movement speed of 2 mm / s is set. For example, when image acquisition is performed four times per second, the threshold of the bright spot movement amount is set to the bright spot movement amount corresponding to the movement amount of the person 2 of 0.5 mm (2 mm / s ÷ 4). To do.

  In addition, the monitoring device 1 may be configured such that a measurement point at which the frequency of movement measured by the FG sensor 10 is equal to or greater than a threshold value is not used for calculation by the calculation means. In the present embodiment, it is configured not to output data of a measurement point whose frequency of motion measured by the measurement device 14 is equal to or greater than a threshold value to the arithmetic device 20. The frequency threshold value may be set to a frequency higher than the breathing frequency of the person, for example, about 60 cycles per minute. By the way, the respiratory rate of an adult is in the range of about 5 to 30 cycles per minute, but in the case of an infant, the respiratory rate tends to increase further. As a result, the measurement point at which the movement of the frequency higher than the respiration frequency is measured can be ignored. By doing so, it is possible to effectively eliminate the influence of movements that are not related to the movement of breathing, such as noise.

  Returning to FIG. 4, the arithmetic unit 20 will be described. The arithmetic device 20 includes a control unit 21 that controls the monitoring device 1. Furthermore, a storage unit 31 is connected to the control unit 21. The storage unit 31 may store the images acquired from the imaging device 12 in time series. The storage unit 31 can store data such as calculated information.

  Connected to the control unit 21 is a display 40 as information output means for outputting information indicating the state of the person 2. The display 40 is typically an LCD. The display 40 outputs, for example, warning data output by a warning data output unit 24 described later, that is, data indicating that there is an abnormality in the breathing of the person 2. In addition, when the waveform data output unit 25 described later is provided as in the present embodiment, the display 40 displays the waveform pattern of the breath of the person 2 output by the waveform data output unit 25 for output. Is configured to do. The display 40 typically displays a respiration waveform pattern in real time. The real-time display means, for example, that the respiration waveform pattern of the person 2 that is output immediately by the waveform data output unit 25 described later is displayed immediately.

  The control unit 21 is connected to an input device 35 for inputting information for operating the monitoring device 1. The input device 35 is, for example, a touch panel, a keyboard, or a mouse. Although the input device 35 is illustrated as being externally attached to the arithmetic device 20 in this figure, it may be incorporated.

  Further, the control unit 21 includes a center coordinate calculation unit 22 as a weighted representative position calculation means for calculating the weighted representative coordinates of the position coordinates of the plurality of measurement points of the FG sensor 10, and movement of the plurality of measurement points. Based on a value weighted by a quantity related to the quantity, a centroid coordinate calculation unit 23 serving as a weighted centroid position calculation means for calculating a weighted centroid coordinate of an area formed by a moving measurement point, unweighted representative coordinates, and weighted centroid When the difference from the coordinates is larger than the threshold value, a warning data output unit 24 is provided as data output means for outputting warning data. In other words, the calculation device 20 includes a center coordinate calculation unit 22, a barycentric coordinate calculation unit 23, and a warning data output unit 24. Further, the amount related to the amount of movement of the plurality of measurement points is, in other words, the amount related to the amount of movement of each of the plurality of measurement points subjected to the calculation of the unweighted representative coordinates.

  Here, among the plurality of measurement points measured by the FG sensor 10, the measurement points that do not move, that is, the measurement points that do not move the bright spot are ignored (excluded) and the above calculation (for example, center coordinates) is performed. , Calculation of barycentric coordinates). In other words, the measurement point used here is a measurement point that has moved.

Here, the unweighted representative coordinates calculated by the center coordinate calculation unit 22 are the average values of the position coordinates of all of the plurality of measurement points, that is, all the measurement points that have moved. Hereinafter, this average value is referred to as center coordinates. The center coordinates are expressed by the following equation.

Center coordinates Xcenter = {Σ (Xi)} ÷ n (1)

Here, n is the number of measurement points forming all measurement points. Xi is the coordinate value of each measurement point. When calculating two-dimensionally, for example, center coordinates Xcenter and Ycenter are calculated with Xi as a coordinate value in the x-axis direction and Yi as a coordinate value in the y-axis direction, respectively. Further, for example, the center coordinates Xcenter-up and Xcenter-down may be calculated according to the upward and downward direction of the movement of the person 2, in other words, according to the moving direction of the bright spot (in the horizontal direction in FIG. 6 (on the image)). .

Further, here, the weighted barycentric coordinates calculated by the barycentric coordinate calculation unit 23 are average values of values obtained by weighting the coordinates of each measuring point in the area formed by the moving measuring point by an amount related to the amount of movement. And Hereinafter, this average value is referred to as a barycentric coordinate. Note that the amount related to the amount of movement is typically the amount of movement of the bright spot at each measurement point. Further, the weight is unsigned (sign of movement direction). That is, the barycentric coordinate is an average value of values obtained by weighting the coordinates of each measurement point with the moving amount of the bright spot. The barycentric coordinates are expressed by the following equation.

Centroid coordinates Xcenter ′ = {Σ (Xi × | ΔZi |)} ÷ Σ | ΔZi | (2)

Here, ΔZi is a weight at each measurement point, that is, a moving amount of the bright spot. | ΔZi | is an unsigned weight at each measurement point, that is, an absolute value of the amount of movement of the bright spot. As in the case of the center coordinate Xcenter, when calculating in two dimensions, for example, the center-of-gravity coordinates Xcenter ′ and Ycenter ′ are calculated using Xi as the coordinate value in the x-axis direction and Yi as the coordinate value in the y-axis direction, respectively.

  The center-of-gravity coordinates are the same as the center coordinates, for example, the center-of-gravity coordinates Xcenter-up ′ according to the upward and downward direction of the movement of the person 2, in other words, according to the moving direction of the bright spot (in the left-right direction in FIG. , Xcenter-down ′ may be calculated. In this case, the center-of-gravity coordinate to be compared with the overall center coordinate is, for example, the larger one of the total sums | Zi | (| Zi_up |, | Zi_down | You may make it evaluate the difference of the below-mentioned center coordinate and a gravity center coordinate. Furthermore, when the center coordinate and the barycentric coordinate are calculated according to the vertical direction of movement (by the moving direction of the bright spot), for example, the larger sum of the moving amounts of bright spots by vertical direction | Zi | You may make it evaluate the difference of the below-mentioned center coordinate and a gravity center coordinate.

  The warning data output unit 24 outputs warning data when the difference between the center coordinates and the barycentric coordinates is larger than a threshold value. Here, the threshold is, for example, about 5 to 20% when the value obtained by dividing the difference between the center coordinates and the center of gravity coordinates by the size of the target area, in other words, the angle of view of the imaging device 12 is represented by%. Good. In this case, it can be seen that the movement of the breathing of the person 2 is clearly a biased movement. When the difference between the center coordinates and the center of gravity coordinates is large, the movement may not be maximum (maximum amplitude) at the center of the portion (region) where the movement is present, but may be maximum at a biased position. . In this case, for example, there may be chronic obstructive pulmonary disease (COPD: chronic obstructive pulmonary disease). By the way, chronic obstructive pulmonary disease is a syndrome that mainly causes obstructive ventilation disorder due to airway disorders and dysfunctions represented by chronic bronchitis, emphysema, diffuse panbronchiolitis and the like. The warning data is data indicating that the breathing of the person 2 is abnormal. The warning data output unit 24 typically outputs warning data in real time. To output in real time is to output warning data immediately when, for example, the difference between the center coordinates and the center of gravity coordinates is larger than a threshold value. The output warning data is output to the display 40 and displayed, for example. Here, the threshold value is described as a value obtained by dividing the difference between the center coordinates and the center of gravity coordinates by the size of the target area, that is, the angle of view of the imaging device 12, but for example, the difference between the center coordinates and the center of gravity coordinates is the target area. In other words, it may be a value divided by the width of the image captured by the imaging device 12 (for example, the width in the x-axis direction, in other words, the length in the direction perpendicular to the baseline direction).

  In addition, when the center coordinates and the center of gravity coordinates are calculated according to the direction of movement, in other words, two-dimensionally calculated, the center coordinates and the center of gravity coordinates are calculated with the larger unsigned weight | ΔZi | Try to see the difference. For example, when | ΔZi | is larger in the y-axis direction, the difference between the center coordinate Ycenter and the center-of-gravity coordinate Ycenter ′ is seen.

  Here, the difference between the center coordinates and the center-of-gravity coordinates will be described in more detail with reference to FIG. In the figure, for the purpose of explanation, the captured image, the angle of view, the position of the measurement point within the angle of view (only the measurement point that has moved), and the person 2 (shown by a broken line in the figure) are shown. However, it is actually calculated only by the numerical value of coordinates. First, the center coordinate calculation unit 22 calculates the center coordinate, and the centroid coordinate calculation unit 23 calculates the centroid coordinate. As shown in the example of (a), when the breathing state of the person 2 is normal, the center coordinate is an average value of the measurement points having movement, and therefore, the region of the measurement point having movement is present. Become the center. Also, the center of gravity coordinates are large in the center of the region and are not biased, so that the center of gravity is in the center of the region where there is a moving measurement point. That is, the difference between the center coordinates and the barycentric coordinates is small. In the drawing, a case is shown in which there is a moving measurement point in a region corresponding to the abdomen and chest of the person 2. That is, in this case, the center coordinates and the center of gravity coordinates are approximately the center of the abdomen and chest.

  Further, as shown in the example of (b), for example, when the breathing state of the person 2 is abnormal, the center coordinate is an average value of the measurement points having movement, and therefore there is a measurement point having movement. It becomes the center of the area. Further, since the center of gravity coordinates are biased in the amount of movement, they are not in the center of the area where the measurement point with movement exists but in a biased position. That is, the difference between the center coordinates and the barycentric coordinates increases. For example, the warning data output unit 24 outputs warning data in such a case.

  Further, the center coordinate calculation unit 22 and the centroid coordinate calculation unit 23 calculate the center coordinate as the unweighted representative coordinate and the centroid coordinate as the weighted centroid coordinate using only the coordinates in the one-dimensional direction of the plurality of measurement points. May be. The one-dimensional direction is, for example, the baseline direction of the FG sensor 10 or the spine direction of the person 2, in other words, the direction perpendicular to the straight line connecting the center of the chest and the center of the abdomen, or the line connecting the centers of the left and right lungs. Note that, for example, in the case of the present embodiment, when the spine direction and the base line direction of the person 2 are approximately the same (see FIG. 2), the one-dimensional direction is the base line direction. The center coordinate calculation unit 22 and the barycentric coordinate calculation unit 23 calculate the center coordinate and the barycentric coordinate using only the baseline direction, that is, the y-axis coordinate (see FIG. 6). In this way, the amount of computation by the computing device 20 can be reduced, so that the processing speed can be increased.

  Further, in the control unit 21, a waveform data output unit 25 that integrates movement data in the height direction of the person 2 measured at a plurality of measurement points and outputs waveform data as information indicating the state of the person 2. Should be provided. The integration of motion data measured at a plurality of measurement points means, for example, calculating the sum of the movement amounts of bright spots at the measurement points, and the output motion waveform data is obtained by calculating the sum in the time direction. It is a waveform pattern formed side by side. The waveform pattern formed in this way indicates the movement of the person 2 breathing. In other words, the output waveform pattern is the breathing waveform pattern of the person 2. In this way, since the breathing waveform pattern of the person 2 can be output, it is possible to grasp the abnormality of the state of the person 2 more accurately. The waveform data output unit 25 is typically configured to output a respiration waveform pattern of the person 2 in real time. To output in real time means to immediately output, for example, the total amount of movement of bright spots measured for each image captured by the imaging device 12. Furthermore, in this case, by outputting this sum in real time, the waveform data output unit 25 outputs a respiration waveform pattern of the person 2 formed side by side in the time direction. The output respiration waveform pattern is displayed on the display 40.

  Here, the waveform data output unit 25 has been described in the case of outputting the waveform pattern to the display 40 in real time, but it may not be in real time. For example, the respiration waveform pattern of the person 2 output from the waveform data output unit 25 may be stored in a storage device (such as a hard disk) such as the storage unit 31. In this case, the warning data output by the warning data output unit 24 is also stored in the storage unit 31. In this way, for example, the stored waveform pattern and warning data can be observed in detail later.

  As described above, the monitoring device 1 is based on the FG sensor 10 that measures the movement in the height direction of the object 2 existing in the target region at a plurality of measurement points, and the plurality of movements measured by the FG sensor 10. Since the calculation device 20 that calculates information indicating the state of the object 2 is provided, for example, information indicating the state of the person 2 can be grasped by referring to the calculation result. Further, the computing device 20 has a motion based on a center coordinate computing unit 22 that calculates the center-of-gravity coordinates of the position coordinates of the plurality of measurement points, and a value weighted by an amount related to the amount of motion of the plurality of measurement points. A center-of-gravity coordinate calculation unit 23 that calculates the center-of-gravity coordinates of the region formed by the measurement point, and a warning data output unit 24 that outputs warning data when the difference between the center coordinates and the center-of-gravity coordinates is greater than a threshold value. Therefore, for example, when the difference between the center coordinates and the center of gravity coordinates is large, it can be seen that the movement of the person 2 due to respiration is a biased movement, and in this case, warning data is output. It is possible to accurately grasp abnormalities in the state.

  Furthermore, the FG sensor 10 projects the pattern on the image captured by the imaging device 12, the projection device 11 that projects the pattern light onto the target region, the imaging device 12 that captures the target region on which the pattern light is projected. And a measuring device 14 for measuring. Further, the measurement device 14 is configured to measure the movement of the person 2 in the height direction at a plurality of points based on the movement of the measured pattern, so that the measurement can be performed in a non-contact manner. The burden on the person 2 is small. Further, by measuring the movement of each bright spot forming the pattern, for example, even a small movement of the person 2 can be measured accurately, so that the movement of the person 2 in the height direction due to breathing can be measured accurately.

  Moreover, since the monitoring apparatus 1 displays the warning data output by the warning data output part 24 on the display 40, it can be easily grasped that the movement of the person 2 due to respiration is biased, for example. That is, an abnormal state can be grasped. This is useful, for example, for diagnosis of chronic lung disease by doctors. Moreover, since the waveform pattern of the breathing of the person 2 output by the waveform data output unit 25 is displayed in real time on the display 40, for example, the state of movement of the person 2 due to breathing can be easily grasped. This is useful, for example, for a doctor's diagnosis.

  In the above description, the pattern projected onto the bed 3 is described as a plurality of bright spots, but bright patterns may be used as shown in FIG. In other words, the movement of the person 2 in the height direction may be measured using a light cutting method. In this case, a projection device 111 configured to project a bright line as pattern light on the bed 3 is used as the projection unit. The number of bright lines to be projected is typically plural, but may be one. Hereinafter, a case where there are a plurality of bright lines will be described. A plurality of bright lines 111b are projected at equal intervals. The plurality of bright lines 111b form a pattern 111a. Further, the direction of the bright line 111b and the base line direction of the trigonometric method are substantially perpendicular. In other words, the direction of the bright line 111 b is perpendicular to the center line in the longitudinal direction of the bed 3.

  In the case of a bright line, for example, as shown in FIG. 9, the bright line image formed on the imaging surface 15 ′ of the image sensor 15 has a height, as in the case of the bright point described in FIG. The object moves in the y-axis direction by δ. Similarly, by measuring this δ, the position of the point on the object can be specified three-dimensionally. Note that δ is measured at the position of the center line of the bright line image. Further, in the case of a bright line, the measurement point corresponds to one pixel of the image sensor 15 at the position of the bright line image.

  As described above, the movement of an arbitrary point on the bright line can be measured by measuring the movement of the bright line by using the pattern light as a plurality of bright lines. The continuous shape of the direction can be recognized. In other words, the resolution of measurement in the bright line direction can be improved.

It is a typical external view showing the outline of the monitoring device which is an embodiment of the invention. It is a typical external view which shows the outline of the monitoring apparatus at the time of using an FG sensor for the three-dimensional sensor which is embodiment of this invention. It is a typical perspective view explaining the projection apparatus which is embodiment of this invention. It is a block diagram which shows the structural example of the monitoring apparatus which is embodiment of this invention. It is a conceptual perspective view explaining the concept of the movement of the bright spot in the embodiment of the present invention. It is a schematic diagram explaining the bright spot imaged on the imaging surface in the case of FIG. It is a schematic plan view explaining the difference between the center coordinates and the center of gravity coordinates according to the embodiment of the present invention. It is a typical external view which shows the outline of the monitoring apparatus at the time of using a some bright line for the pattern light projected with the projector which is embodiment of this invention. It is a schematic diagram explaining the bright line imaged on the imaging surface in the case of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Monitoring apparatus 2 Person 3 Bed 4 Bedding 10 FG sensor (three-dimensional sensor)
DESCRIPTION OF SYMBOLS 11 Projector 11a Pattern 11b Bright spot 12 Imaging device 14 Measuring device 20 Computing device 21 Control unit 22 Center coordinate calculation unit 23 Center of gravity coordinate calculation unit 24 Warning data output unit 25 Waveform data output unit 40 Display 102 Plane 103 Object 105 Light flux generation unit 120 grating 121 optical fiber 122 FG element

Claims (6)

A three-dimensional sensor for measuring the movement in the height direction of the object existing in the object region at a plurality of measurement points;
Computing means for computing information indicating the state of the object based on the plurality of measured movements;
The calculation means includes an unweighted representative position calculation means for calculating unweighted representative coordinates of position coordinates in an area formed by the measurement point that has moved among the plurality of measurement points;
On the basis of the respective position coordinates of the motion of a measuring point in the value obtained by weighting an amount related to the amount of the motion in the measurement point, the weighted center coordinates of the area measurement points were Oh Tsu of the movement to form A weighted centroid position calculating means for calculating;
Data output means for outputting warning data when the difference between the unweighted representative coordinates and the weighted barycentric coordinates is greater than a threshold;
State analysis device. The unweighted representative position calculating means and the weighted centroid position calculating means calculate unweighted representative coordinates and weighted centroid coordinates using only coordinates in one-dimensional direction of the plurality of measurement points;
The state analysis apparatus according to claim 1. The three-dimensional sensor includes a projection device that projects pattern light onto a target region;
An imaging device for imaging a target area onto which the pattern light is projected;
Measuring means for measuring movement of a pattern on the imaged image;
Measuring the movement of the object in the height direction at a plurality of points based on the movement of the measured pattern;
The state analysis apparatus according to claim 1 or 2. Measurement points where the amount of movement measured by the three-dimensional sensor is less than or equal to a threshold value are not used for calculation by the calculation means;
The state analysis apparatus according to any one of claims 1 to 3. Measurement points at which the frequency of movement measured by the three-dimensional sensor is equal to or higher than a threshold value are not used for calculation by the calculation means;
The state analysis apparatus of any one of Claim 1 thru | or 4.   The unweighted representative position calculation means performs a calculation using the average value of all the position coordinates of the measurement point having moved as the unweighted representative coordinates;
  The state analysis device according to any one of claims 1 to 5.

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