JP6756448B2 - Monitoring device - Google Patents

Description

The present invention relates to a monitoring device that recognizes an object existing in a monitoring area.

Conventionally, there has been a technique for detecting and recognizing an object using a camera image. Since the camera image is two-dimensional data, the information obtained from the camera image is also limited to the two-dimensional coordinates, brightness, color, and the like. Most of the prior arts use the brightness background subtraction method to extract a change area in the monitoring area and recognize the object.
However, in many such conventional techniques, there is a problem that the object cannot be recognized accurately when there is no difference in brightness between the object and the background. In addition, since information on the distance of the object cannot be obtained from the two-dimensional data obtained from the camera image, for example, when the object moves in the Z-axis direction (direction straight toward the camera) on the three-dimensional coordinates, There was a problem that the object was recognized as stationary and was not subject to notification.
Therefore, for example, in the monitoring device disclosed in Patent Document 1, distance information to the monitoring area is acquired from the measurement result of the three-dimensional laser scanner, and the difference value between the current distance data and the comparison distance data is calculated. A change area is extracted from the difference value, and based on the extracted change area, recognition processing of whether or not it is a notification target is performed.

International Publication No. 2016/002776

According to the technique described in Patent Document 1 described above, even if there is no difference in brightness, the object is recognized if there is a difference in distance, and even if the object moves in the three-dimensional coordinates in the Z-axis direction, the object is recognized. It is possible to recognize the movement and perform a recognition process of whether or not it is a notification target.
On the other hand, in the distance measurement technique using a three-dimensional laser scanner, the laser beam irradiating the floor may have a shallow incident angle and specular reflection may occur. Therefore, depending on the position from the 3D laser scanner to the floor, the blinking phenomenon that the reflected laser light returns to or does not return to the 3D laser scanner may be repeated irregularly.
Since the technique described in the above-mentioned patent document does not consider that such a blinking phenomenon can occur, there is a problem that an object that does not actually exist may be recognized as existing. there were.

The present invention has been made to solve the above problems, and by fixing the distance from the three-dimensional laser scanner to the floor, an object that should not exist is not mistakenly recognized as an object. It is an object of the present invention to provide a monitoring device capable of such as.

The monitoring device according to the present invention acquires distance data to an object existing in the monitoring area from the measurement result of the three-dimensional laser scanner that measures the monitoring area, and uses the current data calculation unit as the current distance data, and the measurement result. Distance data based on the comparison data calculation unit that acquires past distance data and converts it into comparison distance data, and the floor distance information that defines the distance from the three-dimensional laser scanner to the floor for the current distance data and comparison distance data. The difference value between the correction unit that corrects the above and the corrected current distance data that the correction unit corrected the distance data and the corrected comparison distance data is calculated, and the area where the difference value is equal to or greater than the threshold value is set as the change area. It is provided with a change area extraction unit for extraction.

According to the present invention, by fixing the distance from the three-dimensional laser scanner to the floor, it is possible to prevent an object that should not exist from being mistakenly recognized as an object.

It is a block diagram which shows the structure of the monitoring apparatus which concerns on Embodiment 1. FIG. It is a figure which shows the structure of the 3D laser scanner. It is explanatory drawing which shows the dispersion mechanism of a 3D laser scanner. FIG. 5 is a diagram illustrating an example of the contents of floor-related information stored in the floor-related information storage unit in the first embodiment. It is a flowchart which shows the operation of the monitoring apparatus which concerns on Embodiment 1. FIG. FIG. 5 is a flowchart illustrating details of the operation of step ST505 of FIG. 5 by the floor correction unit in the first embodiment. FIG. 5 is a diagram showing an example of a three-dimensional model in which the field of view of a three-dimensional laser scanner is assembled in a virtual 3D space in the first embodiment. In the first embodiment, an example of a model showing how the floor in the field of view of the three-dimensional laser scanner, the objects A, and the objects B look in the grid of 8 × 4 × 4. 8A is a model showing the positional relationship between the three-dimensional laser scanner and the target A and the target B as viewed from the side. In FIG. 8B, 8 × 4 × 4 grids are in close contact with each other on the left side of the figure. The model shown on the left side of the figure, which is shown on the left side of the figure, is a model in which 8 × 4 × 4 grids are closely attached and sliced horizontally into four so that the entire grid can be seen. Is an image model in which the field of view of a three-dimensional laser scanner is assembled into a virtual image. In the first embodiment, a model showing how the floor in the field of view of the 3D laser scanner looks like in an 8 × 4 × 4 grid in the absence of an object in the monitoring area. This is an example. From the state of the monitoring area shown in the model of FIG. 9, when the target objects A and B intrude into the monitoring area, the floor, the target A, and the target B in the field of view of the three-dimensional laser scanner become This is an example of a model showing what it looks like in an 8x4x4 grid. It is a flowchart which shows the determination process by the recognition processing part of the monitoring apparatus which concerns on Embodiment 1. FIG. 12A and 12B are diagrams showing an example of the hardware configuration of the monitoring device according to the first embodiment of the present invention. It is a block diagram which shows the structure of the monitoring apparatus which concerns on this Embodiment 2. In the second embodiment, the figure for explaining the concept that the virtual floor setting unit sets the “virtual floor”, FIG. 14A shows the three-dimensional laser scanner and the positions of the target A and the target B as viewed from the side. It is a model showing the relationship that the floor is not flat but has convex parts and concave parts in the field of view of the three-dimensional laser scanner. FIG. 14B shows the height of the floor from the state of FIG. 14A. This is a model that represents the corrected state.

Hereinafter, in order to explain the present invention in more detail, a mode for carrying out the present invention will be described with reference to the accompanying drawings.
Embodiment 1.
FIG. 1 is a block diagram showing a configuration of a monitoring device 100 according to a first embodiment.
The monitoring device 100 includes a three-dimensional laser scanner 10, a current data calculation unit 20, a current data storage unit 21, a comparison data calculation unit 30, a comparison data storage unit 31, a change area extraction unit 40, a recognition processing unit 50, and a notification processing unit 60. , A floor correction unit 70, and a floor-related information storage unit 80. The floor correction unit 70 includes a distance acquisition unit 701 and a correction unit 702.
In FIG. 1, a background 200 showing the scanning range of the three-dimensional laser scanner 10 outside the monitoring device 100, an object 201 standing in front of the background 200, and a device above the monitoring device 100, which emits a buzzer or the like. A PC 300 that performs information processing is described. Here, the device above the monitoring device 100 is PC300 as an example, but the device above the monitoring device 100 is not limited to this, and the notification processing in the monitoring device 100 such as a voice output device is not limited to this. Anything that can perform the alarm processing based on is sufficient. Details of the notification process in the monitoring device 100 will be described later.
Further, in the first embodiment, as shown in FIG. 1, the monitoring device 100 includes the floor-related information storage unit 80, but the present invention is not limited to this, and the floor-related information storage unit 80 is outside the monitoring device 100. It may be prepared for. The floor-related information storage unit 80 may be provided at least in a place where the floor correction unit 70 of the monitoring device 100 can refer to the floor-related information storage unit 80.

The three-dimensional laser scanner 10 acquires three-dimensional information of an object 201 or the like existing in the scanning range, and measures the distance or the like to the object 201 or the like.
Here, FIG. 2 is a diagram showing the configuration of the three-dimensional laser scanner 10. As shown in FIG. 2, the three-dimensional laser scanner 10 incorporates a laser emitting unit 11, a dispersion mechanism 13 using a rotating mirror, and a laser receiving unit 16, and scans the range shown in the background 200 to obtain distance data and intensity. Get the data. The laser light emitting unit 11 irradiates the laser light pulse 12.
The dispersion mechanism 13 is a mechanism for dispersing the laser light pulse 12 emitted from the laser light emitting unit 11 in a wide angle range. In the example of FIG. 2, a dispersion mechanism 13 using a rotating mirror is shown. Details of the dispersion mechanism 13 using the rotating mirror will be described later. The dispersed laser light pulse 14 dispersed by the dispersion mechanism 13 is irradiated and reflected on the background 200 or an object (not shown in FIG. 2) to form the laser reflected light 15. In the example of FIG. 2, the dispersed laser beam pulse 14 is sequentially dispersed and irradiated in the X direction and the Y direction of the background 200. Specifically, 6 points in the X direction of the background 200 and 2 points in the Y direction of the background 200, a total of 12 points are dispersed and irradiated.
In FIG. 2, the dispersion mechanism 13 using the rotating mirror is used, but other dispersion mechanisms may be applied. For example, it may be a scanless optical system that scans a mirror without a motor.

The laser light receiving unit 16 receives the laser reflected light 15 reflected by the reflection target, calculates the distance to the reflection target based on the time difference from the light emission to the light reception, and obtains the distance data. In the example of FIG. 2, the distances are individually calculated for all the irradiation positions dispersed in a total of 12 points, 6 points in the X direction of the background 200 and 2 points in the Y direction of the background 200, and used as distance data. Further, the laser light receiving unit 16 calculates the reflectance at each point to be reflected based on the ratio of the irradiated light amount and the received light amount with respect to all the dispersed irradiation positions, and obtains the intensity data. The distance data and intensity data calculated by the laser light receiving unit 16 are output to the current data calculation unit 20 and the comparison data calculation unit 30 shown in FIG.
The distance data and intensity data for all the irradiation positions calculated by the laser light receiving unit 16 are referred to as point cloud data 17.
The output of the point cloud data 17 by the laser light receiving unit 16 to the current data calculation unit 20 and the comparison data calculation unit 30 is performed in frame units. The laser light receiving unit 16 scans the entire background 200 once to obtain point cloud data 17, that is, in the example of FIG. 2, a total of 12 points of 6 points in the X direction and 2 points in the Y direction of the background 200. The point cloud data 17 obtained by one scan for a point is output to the current data calculation unit 20 and the comparison data calculation unit 30 as the point cloud data 17 for one frame.

Next, the details of the dispersion mechanism 13 using the rotating mirror will be described with reference to FIG. The dispersion mechanism 13 includes a first rotary mirror 13a, a first motor 13b, a second rotary mirror 13c, and a second motor 13d. The first rotating mirror 13a operates in synchronization with the pulse frequency of the incident laser light pulse 12, and disperses the laser light pulse 12 in the horizontal direction with respect to the surface of the first rotating mirror 13a. The horizontally dispersed laser beam 13e dispersed in the horizontal direction is always dispersed at the same angle. The first motor 13b is a drive source for driving the first rotary mirror 13a. The second rotating mirror 13c operates in synchronization with the pulse frequency of the incident laser beam pulse 12, and further disperses the horizontally dispersed laser beam pulse 13e in the vertical direction. The vertically dispersed laser beam 13f dispersed in the vertical direction is always dispersed at the same angle. The second motor 13d is a drive source for driving the second rotary mirror 13c.

By the above operation, the three-dimensional laser scanner 10 obtains the following three-dimensional information of X, Y, and Z.
X; Horizontal coordinates Y; Vertical coordinates Z; Distance data In the example of FIG. 2, the horizontal coordinates X are 6 points and the vertical coordinates Y are 2 points. Further, the distance data Z is depth information in the Z-axis direction, and is hereinafter referred to as Z-axis information.
Since the three-dimensional information includes Z-axis information, the Z-axis even when the object moves in the Z-axis direction on the three-dimensional coordinates, that is, when the object goes straight toward the three-dimensional laser scanner 10. The difference can be obtained by using the amount of movement in the direction.

The current data calculation unit 20 acquires the distance data in the point cloud data 17 output from the 3D laser scanner 10, and shows the current distance data in the monitoring area, that is, the measurement range of the 3D laser scanner 10. Is stored in the current data storage unit 21. Here, the current data calculation unit 20 associates the input distance data with the information indicating the grid and stores it in the current data storage unit 21. The grid is an area in a virtual 3D space indicating a measurement point of one point of laser irradiation. The details of the grid will be described later.

The comparison data calculation unit 30 acquires the distance data in the point cloud data 17 output from the three-dimensional laser scanner 10, converts it into comparison data, and stores it in the comparison data storage unit 31. In the conversion process to the comparison data, for example, the average distance data is obtained from the distance data for the past 50 frames from the acquired distance data and used as the comparison data, or the distance data of the frame immediately before the input distance data is used. It may be obtained and used as comparative data. The comparison data calculation unit 30 stores the distance data acquired from the three-dimensional laser scanner 10 in the data storage unit (not shown), and based on the stored distance data, the distance data goes back to the past. Should be obtained. The comparison data calculation unit 30 stores the distance data as the comparison data in the comparison data storage unit 31 in association with the information indicating each grid.
In the first embodiment, the current data is also referred to as the current distance data, and the comparison data is also referred to as the comparison distance data.

The floor correction unit 70 stores the current data stored in the current data storage unit 21 and the comparison data stored in the comparison data storage unit 31 based on the floor-related information stored in the floor-related information storage unit 80. Of the corresponding grids, the distance data is corrected as necessary for the grid corresponding to the floor.
The floor correction unit 70 includes a distance acquisition unit 701 and a correction unit 702.

The distance acquisition unit 701 refers to the floor-related information storage unit 80, and based on the floor-related information stored in the floor-related information storage unit 80, the current data stored in the current data storage unit 21 and the comparison data storage unit 80. The floor distance information corresponding to each grid corresponding to each point of the comparison data accumulated in 31 is acquired. Specifically, the distance acquisition unit 701 includes each grid corresponding to each point of the current data and each point of the comparison data, and grid information of the floor-related information stored in the floor-related information storage unit 80. Make a match, identify the corresponding floor distance information, and acquire the floor distance information.

Here, FIG. 4 is a diagram illustrating an example of the contents of the floor-related information stored in the floor-related information storage unit 80 in the first embodiment.
The floor-related information is information that identifies the grid (hereinafter referred to as "grid information") and information indicating the distance from the three-dimensional laser scanner 10 to the floor portion included in each grid (hereinafter referred to as "floor distance information"). ) Is the information. In the floor-related information storage unit 80, for example, as shown in FIG. 4, the grid information and the floor distance information are associated with each other, and the floor-related information is stored in a table format.
The grid information consists of an X-direction grid and a Y-direction grid. The X-direction grid is information indicating the number of the grid when counted in order in the X-axis direction. The Y-direction grid is information indicating the number of the grid when counted in order in the Y-axis direction. The floor distance information is information indicated in units of distance such as m (meter).

For example, in the floor-related information shown in FIG. 4, for a grid having an X-direction grid of 1 and a Y-direction grid of 1, the floor portion included in the grid has a distance of 0 m from the three-dimensional laser scanner 10. Is defined, and for a grid with an X-direction grid of 1 and a Y-direction grid of 2, the floor portion included in the grid is defined to have a distance of 20 m from the three-dimensional laser scanner 10. .. Further, for example, for a grid having an X-direction grid of 1 and a Y-direction grid of 3, the floor portion included in the grid is defined to have a distance of 40 m from the three-dimensional laser scanner 10.
Further, the floor distance information is defined as "none" for the grid in which the X-direction grid is 1 and the Y-direction grid is 4, because the floor is not included. That is, for a grid in which the X-direction grid is 1 and the Y-direction grid is 4, all grids include "other than the floor".
When the floor distance information is defined as "none", specifically, the floor distance information is set to the maximum value that the floor distance information can take, such as "infinity".

Further, in FIG. 4, regarding the grid information, the information of the Z direction grid is omitted. This is because the information about the "floor" is defined for the XY plane and is a fixed value for the Z direction grid.
The content of the floor-related information shown in FIG. 4 is only an example. The floor-related information may include information other than that shown in FIG. 4, and may include at least the contents shown in FIG. Further, the floor-related information does not have to be data in a table format as shown in FIG.

The floor-related information is stored in the floor-related information storage unit 80 in advance by, for example, being input by an operator or the like from an input device (not shown).
As a specific input method, for example, an operator or the like may input floor distance information for each of the X-direction grid or the Y-direction grid. When the input device receives an input from an operator or the like, the storage control unit (not shown) of the monitoring device 100 stores the received input content as floor-related information in the floor-related information storage unit 80.

Further, for example, when it can be assumed that there is no difference in the floor distance information in the X direction grid, the operator or the like uses a certain grid in the X direction grid as the representative grid, and the floor distance information for each Y direction grid with respect to the representative grid. You may enter only. Specifically, for example, the operator has 1 X-direction grid and 1 Y-direction grid, 1 X-direction grid and 2 Y-direction grids, 1 X-direction grid and 3 Y-direction grids, and X. Input the floor distance information of four points where the direction grid is 1 and the Y direction grid is 4. Then, for example, the memory control unit receives the floor-related information of the four points, and the floor distance information of the Y-direction grid associated with the X-direction grid other than the X-direction grid 1 is associated with the X-direction grid 1, respectively. The floor distance information of the same Y-direction grid may be copied to create floor-related information, which may be stored in the floor-related information storage unit 80.

For example, the distance acquisition unit 701 acquires the floor distance information of the grid (X-direction grid, Y-direction grid, Z-direction grid) = (1, 2, 1) for the current data stored in the current data storage unit 21. In this case, the grid of the floor-related information with the X-direction grid of 1 and the Y-direction grid of 2 is searched, and 20 m is acquired as the floor distance information.
The distance acquisition unit 701 adds the acquired floor distance information to each grid corresponding to each point of the current data or the comparison data, and outputs the acquired floor distance information to the correction unit 702.

The correction unit 702 is out of each grid for each point of the current data stored in the current data storage unit 21 and the comparison data stored in the comparison data storage unit 31 based on the floor distance information acquired from the distance acquisition unit 701. , For the grid corresponding to the "floor", the distance data is corrected as necessary.
Specifically, the correction unit 702 compares the distance based on the distance data and the distance based on the floor distance information for each grid of the current data and the comparison data for each point, and each of the current data or the comparison data. If the distance based on the distance data in each grid corresponding to the points is larger than the distance based on the floor distance information, the distance data of the corresponding grid is replaced with the distance based on the floor distance information.
The correction unit 702 uses the current data and the comparison data after replacing the distance data of the corresponding grid with the floor distance information as the corrected current data or the corrected comparison data, and outputs the corrected area extraction unit 40.

Note that the correction unit 702 keeps the contents of the grid distance data that is not replaced by the floor distance information as it is. Therefore, the current data or the comparison data for which the distance data does not need to be replaced in all the grids is output as it is to the change area extraction unit 40 as the corrected current data or the corrected comparison data.

Further, here, if the distance of the current data or the comparison data based on the distance data in each grid corresponding to each point is larger than the distance based on the floor distance information, the correction unit 702 displays the distance data of the corresponding grid. The distance is replaced with the distance based on the floor distance information, but the correction method is not limited to this. For example, if the distance based on the distance data in each grid with respect to each point of the current data or the comparison data is larger than the distance based on the floor distance information, the correction unit 702 replaces the distance data of the corresponding grid with "infinity". You may do so.

When the data is replaced with the floor distance information, the corrected current data or the corrected comparison data, which is the distance data after the replacement, has a continuous value, so that the data does not have a sense of discomfort.
On the other hand, when replacing with "infinity", the processing load can be reduced because all the replacement values are the same in the current data or the comparison data of each grid.

The floor-related information storage unit 80 stores the grid information of each grid and the floor distance information associated with the grid information (see, for example, FIG. 4).

The change area extraction unit 40 acquires the corrected current data and the corrected comparison data from the correction unit 702 of the floor correction unit 70, compares the corrected current data and the corrected comparison data on a pixel-by-pixel basis, and calculates a difference value. Then, the pixel region in which the calculated difference value is equal to or larger than the preset threshold value is extracted as the change region. Generally, a fixed threshold value is set, and the data is converted into binarized data that is binarized depending on whether or not the difference value is equal to or greater than the set threshold value. Since the corrected current data and the corrected comparison data are composed of distance data, the difference value calculated by the change area extraction unit 40 indicates a “distance difference”. For example, when the corrected current data includes the background 200 and the object 201, and the corrected comparison data includes only the background 200, the obtained difference value is "the distance between the corrected background and the object". Is shown.

The recognition processing unit 50 extracts feature quantities such as "area", "vertical and horizontal dimensions", and "speed" from the change region extracted by the change region extraction unit 40, and the extracted feature quantities satisfy predetermined collation conditions. Based on whether or not the change area is the notification target, the recognition process is performed. When the recognition processing unit 50 recognizes that the change area is the notification target, the recognition processing unit 50 outputs the notification instruction information to the notification processing unit 60.
The notification processing unit 60 performs notification processing based on the notification instruction information output from the recognition processing unit 50. Examples of the notification process include a process of transmitting a specific signal to a device such as a higher-level PC 300, a process of causing the device to sound a buzzer, and the like.

In the first embodiment, as shown in FIG. 1, the three-dimensional laser scanner 10 is provided in the monitoring device 100, but the present invention is not limited to this, and the three-dimensional laser scanner 10 is outside the monitoring device 100. The monitoring device 100 may be provided to acquire point group data 17 from the three-dimensional laser scanner 10 via a network or the like.

Next, the operation of the monitoring device 100 according to the first embodiment will be described.
FIG. 5 is a flowchart showing the operation of the monitoring device 100 according to the first embodiment.
Here, for the sake of brevity, the case where the resolution of the three-dimensional laser scanner 10 is 8 × 4 pixels will be described as an example.
First, the three-dimensional laser scanner 10 scans the background 200, that is, the range of the monitoring area (step ST501), and acquires the point cloud data 17, that is, the distance data and the intensity data (step ST502). Specifically, the range of the background 200 is divided into 8 × 4, which is the resolution of the three-dimensional laser scanner 10, and scanned. The distance data is generally digital data, and here, it is multi-valued data of 8 bits per pixel of 8 × 4 pixels.
The three-dimensional laser scanner 10 outputs the acquired point cloud data to the current data calculation unit 20 and the comparison data calculation unit 30.
The current data calculation unit 20 stores the distance data in the point cloud data 17 of 8 × 4 pixels acquired in step ST502 as the current data in the current data storage unit 21 (step ST503).
The comparison data calculation unit 30 converts the distance data in the point cloud data 17 of 8 × 4 pixels acquired in step T502 in the past and stored in the data storage unit (not shown) into comparison data, and the comparison data storage unit 31 (Step ST504).

The floor correction unit 70 stores the current data stored in the current data storage unit 21 and the comparison data stored in the comparison data storage unit 31 based on the floor-related information stored in the floor-related information storage unit 80. Of the corresponding grids, the distance data is corrected as necessary for the grid corresponding to the floor (step ST505).

Here, FIG. 6 is a flowchart illustrating the details of the operation of step ST505 of FIG. 5 by the floor correction unit 70 in the first embodiment.
The distance acquisition unit 701 of the floor correction unit 70 refers to the floor-related information storage unit 80, and based on the floor-related information stored in the floor-related information storage unit 80, the current data stored in the current data storage unit 21 and the current data. , The floor distance information corresponding to each grid corresponding to each point of the comparison data accumulated in the comparison data storage unit 31 is acquired (step ST601).
The distance acquisition unit 701 adds the acquired floor distance information to each grid for each point of the current data or the comparison data, and outputs the acquired floor distance information to the correction unit 702.

The correction unit 702 uses the distance based on the distance data and the floor distance information for each grid corresponding to each point of the current data stored in the current data storage unit 21 and the comparison data stored in the comparison data storage unit 31. It is compared with the base distance and it is determined whether the distance of the current data or the comparison data based on the distance data in each grid for each point is larger than the distance based on the floor distance information (step ST602).

In step ST602, when the distance of the current data or the comparison data based on the distance data in each grid corresponding to each point is larger than the distance based on the floor distance information (when “YES” in step ST602), the correction unit 702 , Correct the distance data of the corresponding grid (step ST603). Specifically, the correction unit 702 replaces the distance data of the grid determined that the distance based on the distance data is larger than the distance based on the floor distance information with the floor distance information.

Normally, the distance data of the current data or the comparison data in each grid corresponding to each point cannot show a value larger than the distance from the 3D laser scanner 10 to the floor included in the grid. However, in rare cases, for example, an event may occur in which the incident angle of the dispersed laser light pulse 14 irradiated by the three-dimensional laser scanner 10 on the floor becomes shallow. As a result, specular reflection may occur, the reflected laser reflected light 15 may not return to the three-dimensional laser scanner 10 correctly, and correct distance data may not be obtained. Due to the blinking phenomenon in which such a phenomenon is repeated irregularly, there is a possibility that the difference will be extracted in the processing by the change area extraction unit 40 described later. That is, the "floor" may not be recognized as the "floor" but may be recognized as an object 201 other than the floor.

Therefore, when the correction unit 702 indicates a distance at which the distance data cannot exist so as not to erroneously recognize the nonexistent object 201, for example, it is assumed that a blinking phenomenon has occurred, and the distance indicating a predefined "floor" is indicated. Correct so that

In step ST602, when the distance of the current data or the comparison data based on the distance data in each grid corresponding to each point is not larger than the distance based on the floor distance information, that is, it corresponds to each point of the current data or the comparison data. If the distance based on the distance data in each grid is equal to or less than the distance based on the floor distance information (“NO” in step ST602), step ST603 is skipped.

For the grid to be determined in step ST602, if the distance based on the distance data in the grid is equal to the distance based on the floor distance information, the "floor" is normally detected, so the distance data is corrected. unnecessary.
Further, regarding the grid to be determined in step ST602, when the distance based on the distance data in the grid is less than the distance based on the floor distance information, it is considered that the object 201 entering the monitoring area is detected. In this case, since the distance data in the grid to be determined is not the distance data in the grid corresponding to the “floor”, it is not necessary to correct the distance data.

As described above, for a grid that does not correspond to "floor", the floor distance information is defined as "none", and the maximum value that the floor distance information can take, such as "infinity", is set and is related to the floor. It is stored in the information storage unit 80.
Further, the distance of the object 201 that has entered the monitoring area from the three-dimensional laser scanner 10 is always smaller than the distance from the three-dimensional laser scanner 10 to the floor.
Therefore, in step ST602, with respect to the grid corresponding to the object 201 that has invaded the monitoring area, the distance based on the distance data in the grid does not exceed the distance based on the floor distance information, and the processing in step ST603 is skipped. Therefore, the distance data in the grid is not corrected.

Here, FIG. 7 is a diagram showing an example of a three-dimensional model in which the field of view of the three-dimensional laser scanner 10 is assembled in a virtual 3D space in the first embodiment.
In FIG. 7, one cube indicates a measurement point of one point of laser irradiation, and the size of the space is 8 × 4 × 4. One cube indicates a measurement point of one point of laser irradiation, and the measurement point is referred to as a grid here.

FIG. 8 shows how the floor 803 in the field of view of the three-dimensional laser scanner 10 and the objects A801 and B802, which are the objects 201, appear in the 8 × 4 × 4 grid in the first embodiment. This is an example of a model showing that.
FIG. 8A is a model showing the positional relationship between the three-dimensional laser scanner 10 and the target A801 and the target B802 as viewed from the side. Further, FIG. 8B shows a model in which 8 × 4 × 4 grids are in close contact with each other on the left side of the figure, and a model in which 8 × 4 × 4 grids are in close contact with each other on the right side of the figure. , It is a model that slices horizontally into four so that the entire grid can be seen. Further, FIG. 8C is an image model in which the field of view of the three-dimensional laser scanner 10 is assembled into a virtual image.

As shown in FIG. 8C, the floor 803 appears to be higher as it goes deeper due to the depression angle of the three-dimensional laser scanner 10. Further, although the target A801 and the target B802 have the same size, the target 802 in the back is measured smaller.

In FIGS. 8A to 8B, the grids other than the grids corresponding to the floor 803, the target A801, and the target B802 are grids for which a distance could not be obtained by the three-dimensional laser scanner 10. In the first embodiment, the grid for which the distance cannot be obtained by the three-dimensional laser scanner 10 is also referred to as a blank grid 804.

As shown in FIGS. 7 and 8, the field of view of the three-dimensional laser scanner 10 corresponds to an object corresponding to the “floor” such as the floor 803 and an object “other than the floor” such as the target A801 and the target B802. There is an object 201. However, it is not possible to distinguish whether the grid corresponding to each point of the point cloud data 17 corresponds to the "floor" or "other than the floor" only by the information obtained from the three-dimensional laser scanner 10. That is, the point cloud data 17 output from the three-dimensional laser scanner 10 does not include information on whether it corresponds to the “floor” or “other than the floor”.

On the other hand, as described above, in rare cases, for example, an event may occur in which the incident angle of the dispersed laser light pulse 14 irradiated by the three-dimensional laser scanner 10 on the floor becomes shallow, which causes specular reflection and reflection. It is possible that the reflected laser light 15 does not return to the three-dimensional laser scanner 10 correctly and the correct distance data cannot be obtained. Specifically, the distance data of the current data or the comparison data in each grid corresponding to each point may show a value larger than the distance from the 3D laser scanner 10 to the floor included in the grid. ..
When such a blinking phenomenon occurs, it is not recognized as a "floor" and may be recognized as an object 201 other than the floor. Therefore, in order to prevent the false recognition, it corresponds to the "floor". Despite this, it is necessary to correct the distance data of the grid for which the correct distance data could not be obtained to the correct distance data.
Therefore, in the first embodiment, the floor distance information is defined in advance, stored in the floor-related information storage unit 80 as the floor-related information associated with the grid information, and based on the floor distance information, 3 When the distance based on the distance data from the dimensional laser scanner 10 is larger than the distance based on the floor distance information, that is, when the grid corresponds to the "floor" where the correct distance data could not be obtained due to the blinking phenomenon or the like. The distance data of the grid is replaced with the floor distance information and corrected to the correct distance data.

FIG. 9 shows how the floor 803 in the field of view of the 3D laser scanner 10 looks like in an 8 × 4 × 4 grid in the first embodiment in the absence of the object 201 in the monitoring area. This is an example of a model showing whether or not it is used.
On the left side of the figure, the model with 8x4x4 grids in close contact, and on the right side of the figure, the model with 8x4x4 grids in close contact, shown on the left side of the figure, are divided into four horizontally. This model is sliced so that the entire grid can be seen.
Further, FIG. 10 shows the floor 803 in the field of view of the three-dimensional laser scanner 10 when the objects A801 and B802, which are the objects 201, invade the monitoring area from the state of the monitoring area shown in the model of FIG. , A801, and B802 are examples of a model showing how the objects A801 and B802 look in an 8x4x4 grid.

In addition, in FIGS. 9 and 10, the grid of (X direction grid, Y direction grid, Z direction grid) = (1, 2, 1) shown by grid 803'is corrected by the correction unit 702, and the distance data is obtained. Is a grid replaced with the floor distance information of the floor-related information.

When the target A801 and the target B802 invade, the target A801 and the target B802 are not seen farther than the floor 803 when viewed from the three-dimensional laser scanner 10. If the target A801 and the target B802 are seen farther than the floor 803 when viewed from the three-dimensional laser scanner 10, the target A801 and the target B802 are buried in the floor 803, which is an unrealistic state. It becomes.
That is, the distance from the three-dimensional laser scanner 10 to the target A801 and the distance from the three-dimensional laser scanner 10 to the target B802 are always smaller than the distance from the three-dimensional laser scanner 10 to the floor.

Therefore, as described above, even if the correction unit 702 replaces the distance data with the floor distance information when the distance indicated by the distance data is larger than the distance based on the floor distance information, the distance indicating the distance to the object 201 is indicated. By replacing the data, the distance from the three-dimensional laser scanner 10 to the object 201 can be accurately acquired without losing sight of the object 201.
Further, for example, even when the blinking phenomenon as described above occurs, the correction unit 702 replaces the distance data with the floor distance information and fixes the floor distance to the distance defined in advance as “floor”. The grid that should correspond to the floor will not be mistakenly recognized as if the object 201 exists.

Return to the flowchart of FIG.
The correction unit 702 uses the current data and the comparison data after replacing the distance data of the corresponding grid with the floor distance information as necessary as the corrected current data and the corrected comparison data, respectively, in the change area extraction unit 40. Output (step ST604).

As described above, the floor correction unit 70 uses the current data stored in the current data storage unit 21 and the comparison data stored in the comparison data storage unit 31 as the current data or the comparison data of the grid corresponding to the floor. On the other hand, correction is performed as necessary.
Then, the floor correction unit 70 uses the corrected current data based on the corrected grid as the corrected current data and the corrected comparison data based on the corrected grid as the corrected comparison data. , Is output to the change area extraction unit 40.
The floor correction unit 70 performs the above-described processing based on, for example, a grid based on the latest current data stored in the current data storage unit 21 and the latest comparison data stored in the comparison data storage unit 31. Try to target the grid.

Return to the flowchart of FIG.
The change area extraction unit 40 acquires the corrected current data output from the floor correction unit 70 and the corrected comparison data, compares the corrected current data and the corrected comparison data on a pixel-by-pixel basis, and obtains a difference value. Calculate (step ST506). In the process of step ST506, since the corrected current data and the corrected comparison data are composed of distance data, the difference value calculated by the change area extraction unit 40 indicates a “distance difference”. For example, when the corrected current data includes the background 200 and the object 201, and the corrected comparison data includes only the background 200, the obtained difference value is "the background of the comparison data and the object of the current data. The distance between them is shown.

The difference value obtained in step ST506 is multi-valued data of 8 bits per pixel, and the change area extraction unit 40 determines whether or not the obtained difference value is equal to or greater than a preset threshold value (step ST507). ). When the difference value is equal to or greater than the threshold value (when “YES” in step ST507), the pixel region is extracted as a change region (step ST508). The change area extraction unit 40 outputs the extracted information of the change area to the recognition processing unit 50.
On the other hand, when the difference value is less than the threshold value (when “NO” in step ST507), it is determined that the pixel region is not a change region (step ST509), and the process proceeds to step ST510. After that, the change area extraction unit 40 determines whether or not all the 8 × 4 pixels have been processed (step ST510). If all 8 × 4 pixels have not been processed (“NO” in step ST510), the process returns to step ST506 and the above processing is repeated.

On the other hand, when processing is performed on all 8 × 4 pixels (when “YES” in step ST510), the recognition processing unit 50 determines whether or not the change region extracted in step ST508 satisfies the collation condition (when the processing is performed (when “YES” in step ST510). Step ST511). When the collation condition is satisfied (“YES” in step ST511), the recognition processing unit 50 recognizes that the change area is the notification target (step ST512). When the recognition processing unit 50 recognizes that the change area is the notification target, the recognition processing unit 50 outputs the notification instruction information to the notification processing unit 60.
On the other hand, if the collation condition is not satisfied (“NO” in step ST511), it is determined that the change area is not the notification target (step ST513), and the process returns to step ST501.

Here, the determination process by the recognition processing unit 50 in step ST511 will be described in detail.
FIG. 11 is a flowchart showing a determination process by the recognition processing unit 50 of the monitoring device 100 according to the first embodiment.
The recognition processing unit 50 determines whether or not the change region exists within the monitoring range (step ST1101). Here, the monitoring range is a monitoring area, that is, a range within the measurement range of the three-dimensional laser scanner 10, and for example, a range for which notification is required when the object 201 is detected due to the need for monitoring. It is assumed that the monitoring range is set in advance.
When the change area exists within the monitoring range (when “YES” in step ST1101), the recognition processing unit 50 further determines whether or not the change area has a predetermined area (step ST1102). The change region referred to here refers to a region consisting of a set of a plurality of pixels adjacent to or close to each other among the pixels extracted as the change region in step ST508 of FIG.
When the change area has a predetermined area (when “YES” in step ST1102), the recognition processing unit 50 further determines whether or not the change area has a predetermined vertical and horizontal dimensions (step). ST1103). When it has a predetermined vertical and horizontal dimensions (when “YES” in step ST1103), the recognition processing unit 50 further determines whether or not the change region has a predetermined moving speed (step ST1104). .. When the moving speed has a predetermined speed (when “YES” in step ST1104), the process proceeds to step ST512 in FIG. 5, and the change region is recognized as the notification target.

On the other hand, when the change area does not exist within the monitoring range (when “NO” in step ST1101), or when the change area does not have a predetermined area (when “NO” in step ST1102), or When the changing area does not have a predetermined vertical and horizontal dimension (when "NO" in step ST1103), or when the changing area does not have a predetermined moving speed (when "NO" in step ST1104). , Step ST513 of FIG. 5, and it is determined that the notification target is not applicable.

Return to the flowchart of FIG.
The notification processing unit 60 performs notification processing on the recognized notification target based on the notification instruction information output from the recognition processing unit 50 in step ST512 (step ST514), and returns to the processing of step ST501.

12A and 12B are diagrams showing an example of the hardware configuration of the monitoring device 100 according to the first embodiment of the present invention.
In the first embodiment of the present invention, the functions of the current data calculation unit 20, the comparison data calculation unit 30, the change area extraction unit 40, the recognition processing unit 50, the notification processing unit 60, and the floor correction unit 70 are , Realized by the processing circuit 1201. That is, the monitoring device 100 includes a processing circuit 1201 for performing notification processing when a change to be notified is detected based on the point cloud data acquired from the three-dimensional laser scanner 10.
The processing circuit 1201 may be dedicated hardware as shown in FIG. 12A, or may be a CPU (Central Processing Unit) 1206 that executes a program stored in the memory 1205 as shown in FIG. 12B.

When the processing circuit 1201 is dedicated hardware, the processing circuit 1201 may be, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), or an FPGA (Field-Programmable). Gate Array), or a combination of these.

When the processing circuit 1201 is the CPU 1206, the functions of the current data calculation unit 20, the comparison data calculation unit 30, the change area extraction unit 40, the recognition processing unit 50, the notification processing unit 60, and the floor correction unit 70 are It is realized by software, firmware, or a combination of software and firmware. That is, the current data calculation unit 20, the comparison data calculation unit 30, the change area extraction unit 40, the recognition processing unit 50, the notification processing unit 60, and the floor correction unit 70 are HDD (Hard Disk Drive) 1202 and memory. It is realized by a CPU 1206 that executes a program stored in 1205 or the like, or a processing circuit such as a system LSI (Large-Scale Integration). The programs stored in the HDD 1202, the memory 1205, or the like include the current data calculation unit 20, the comparison data calculation unit 30, the change area extraction unit 40, the recognition processing unit 50, the notification processing unit 60, and the floor. It can also be said that the procedure and method of the correction unit 70 are executed by the computer. Here, the memory 1205 is, for example, a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an EPROM (Erasable Programmable Read Online Memory), an EEPROM (Electrically Memory), or an EEPROM (Electrically Memory). A sexual or volatile semiconductor memory, a magnetic disk, a flexible disk, an optical disk, a compact disk, a mini disk, a DVD (Digital Versaille Disc), or the like is applicable.

Note that some of the functions of the current data calculation unit 20, the comparison data calculation unit 30, the change area extraction unit 40, the recognition processing unit 50, the notification processing unit 60, and the floor correction unit 70 are dedicated hardware. It may be realized by hardware and partly by software or firmware. For example, the current data calculation unit 20 and the comparison data calculation unit 30 are realized by the processing circuit 1201 as dedicated hardware, and the change area extraction unit 40, the recognition processing unit 50, and the notification processing unit 60 The function of the floor correction unit 70 can be realized by the processing circuit reading and executing the program stored in the memory 1205.
The current data storage unit 21, the comparison data storage unit 31, and the floor-related information storage unit 80 use, for example, HDD 1202. Note that this is only an example, and the current data storage unit 21, the comparison data storage unit 31, and the floor-related information storage unit 80 may be configured by a DVD, a memory 1205, or the like.
Further, the monitoring device 100 includes a three-dimensional laser scanner 10, an input interface device 1203 that communicates with a device such as a PC 300 on the upper level, and an output interface device 1204.

As described above, according to the first embodiment, the current data obtained by acquiring the distance data to the object existing in the monitoring area from the measurement result of the three-dimensional laser scanner 10 measuring the monitoring area and using it as the current distance data. The distance from the 3D laser scanner 10 to the floor is defined for the calculation unit 20, the comparison data calculation unit 30 that acquires the past distance data from the measurement result and converts it into the comparison distance data, and the current distance data and the comparison distance data. Based on the floor distance information, the correction unit 702 that corrects the distance data, the corrected current distance data that the correction unit 702 corrected the distance data, and the corrected comparative distance data are calculated, and the difference value is calculated. Since it is configured to include a change area extraction unit 40 that extracts a region whose difference value is equal to or greater than the threshold value as a change region, by fixing the distance from the 3D laser scanner to the floor, an object that should not exist It is possible to improve the recognition accuracy of an object existing in the monitoring area without erroneously recognizing 201.

Further, since the correction unit 702 corrects the distance data for the current distance data and the comparison distance data when the distance based on the distance data is larger than the distance based on the floor distance information, the three-dimensional laser scanner 10 is used for the floor. Even when a specular reflection occurs with respect to the laser light radiated to the data and the blinking phenomenon that the laser reflected light 15 returns or does not return is repeated, it is possible to prevent the blinking phenomenon from being mistakenly recognized as the object 201. ..

Embodiment 2.
In the first embodiment, when the operator corresponds to the “floor” for each grid corresponding to each point of the point group data 17 obtained by scanning the field of view of the three-dimensional laser scanner 10 in advance, three-dimensional. The floor distance information from the laser scanner 10 to the "floor" is set, and the floor correction unit 70 sets the "floor" as necessary based on the floor distance information set for each grid. The distance data of the grid corresponding to was corrected.
In the second embodiment, the operator or the like further sets the distortion correction information for correcting the height of the "floor" in advance, and the floor correction unit 70 is based on the distortion correction information. , An embodiment of setting a virtual floor will be described.

FIG. 13 is a block diagram showing a configuration of the monitoring device 100a according to the second embodiment.
In FIG. 13, the same components as those of the monitoring device 100 described with reference to FIG. 1 in the first embodiment are designated by the same reference numerals and duplicated description will be omitted.
The monitoring device 100a according to the second embodiment further includes a distortion correction information storage unit 90 and a floor correction unit 70a further includes a virtual floor setting unit 703, respectively, as compared with the monitoring device 100 according to the first embodiment. Is different.
The distortion correction information storage unit 90 stores distortion correction information for correcting the height of the “floor”.
The distortion correction information is set in advance by an operator or the like when, for example, a floor that is not flat exists in the monitoring area.

In the second embodiment, as shown in FIG. 13, the monitoring device 100a is provided with the distortion correction information storage unit 90, but the present invention is not limited to this, and the distortion correction information storage unit 90 is outside the monitoring device 100a. It may be prepared for. The strain correction information storage unit 90 may be provided so that at least the floor correction unit 70a of the monitoring device 100a is provided in a place where the strain correction information storage unit 90 can be referred to.

The virtual floor setting unit 703 of the floor correction unit 70a sets a “virtual floor” in which the height of the floor is corrected based on the strain correction information stored in the strain correction information storage unit 90.
Specifically, the virtual floor setting unit 703 has a height range indicated by distortion correction information among the grids existing above the Y-axis direction of the grid stored as the “floor” in the floor-related information storage unit 80. The grid inside is set as a virtual floor, and the distance from the three-dimensional laser scanner 10 is calculated and set. Alternatively, the virtual floor setting unit 703 is a grid within the height range indicated by the strain correction information among the grids existing below the Y-axis direction of the grid stored as the “floor” in the floor-related information storage unit 80. Is set as a virtual floor, and the distance from the three-dimensional laser scanner 10 is calculated and set. As a result, the virtual floor setting unit 703 raises or lowers the actual floor and sets it as a "virtual floor".
The virtual floor setting unit 703 sets the distance from the three-dimensional laser scanner 10 in the grid raised or lowered to form a "virtual floor" with the floor distance information stored in the floor-related information storage unit 80. , The calculation may be made based on the distortion correction information and the depression angle of the "floor" seen from the three-dimensional laser scanner 10. It is assumed that the depression angle of the "floor" seen from the three-dimensional laser scanner 10 is known in advance.
The virtual floor setting unit 703 uses the calculated distance from the three-dimensional laser scanner 10 to the “virtual floor” as the “virtual floor” as the floor distance information of the grid, which is stored in the floor-related information storage unit 80. Set to the floor distance information of the information.

Since the hardware configuration of the monitoring device 100a according to the third embodiment is the same as the configuration described with reference to FIGS. 12A and 12B in the first embodiment, duplicate description will be omitted.
The distortion correction information storage unit 90 uses, for example, HDD 1202. This is only an example, and the distortion correction information storage unit 90 may be composed of a DVD, a memory 1205, or the like.

Regarding the operation of the monitoring device 100a according to the second embodiment, the specific operation of the floor correction unit 70a is the same as the specific operation of the floor correction unit 70 in the first embodiment (step ST505 in FIG. 5). Since they are different only, a duplicate description will be omitted for the same operation as in the first embodiment.
In the monitoring device 100a according to the second embodiment, first, the virtual floor setting unit 703 sets a “virtual floor” whose floor height is corrected based on the strain correction information stored in the strain correction information storage unit 90. ..
After that, the operation described with reference to FIG. 6 in the first embodiment is performed.
The floor distance information stored in the floor-related information storage unit 80 by the virtual floor setting unit 703 includes the distance from the three-dimensional laser scanner 10 preset by the user to the floor portion included in each grid. The information to be shown and the information indicating the distance from the three-dimensional laser scanner 10 calculated by the virtual floor setting unit 703 to the virtual floor included in each grid are set.

Here, FIG. 14 is a diagram for explaining the concept that the virtual floor setting unit 703 sets the “virtual floor” in the second embodiment.
FIG. 14A shows the positional relationship between the three-dimensional laser scanner 10 and the target A801 and the target B802 as viewed from the side. In the field of view of the three-dimensional laser scanner 10, the floor 803 is not flat, and the convex portion 8031 and the concave portion 8032 are formed. It is a model that represents the state of having. Further, FIG. 14B is a model showing a state in which the height of the floor 803 is corrected from the state of FIG. 14A.
In FIGS. 14A and 14B, when the floor 803 has a height of 0 m, the convex portion 8031 is a protrusion of the floor 803 having a height of 0.2 m, and the recess 8032 is a recess of the floor 803 having a height of −0.1 m. Suppose that

In the second embodiment, the distortion correction information storage unit 90 stores distortion correction information set in advance by an operator or the like. Here, for example, it is assumed that ± 0.3 m is stored as distortion correction information.
By setting the strain correction information, the height of the floor 803 can be corrected by the amount of the strain correction information to obtain a "virtual floor". Specifically, here, the floor 803a is raised from the floor 803 to a height of 0.3 m in parallel with the floor 803, and the floor 803b is raised from the floor 803 to a height of −0.3 m in parallel with the floor 803. And can be specified, and floors 803a to 803b can be designated as "virtual floors". That is, a space having a height of ± 0.3 m from the floor 803 can be regarded as a “virtual floor”.

As shown in FIG. 14A, before the correction of the floor 803, that is, before setting the “virtual floor”, there are a convex portion 8031 and a concave portion 8032, and in the convex portion 8031 and the concave portion 8032, the three-dimensional laser scanner 10 The same distance as the distance from the floor to the floor 803 cannot be obtained, and the convex portion 8031 and the concave portion 8032 may be recognized as the target A801, the target B802, or other object 201.

On the other hand, as shown in FIG. 14B, by setting the floors 803a to 803b as "virtual floors", the floor 803 can be regarded as a flat floor having no convex portion 8031 and concave portion 8032.
As a result, for example, at the position of the convex portion 8031 or the concave portion 8032, only the true object 201 can be recognized without recognizing the floor 803 as the object 201.

In the above example, the distortion correction information is ± 0.3 m, but the distortion correction information is not limited to this, and the distortion correction information can be appropriately set by the operator or the like.
For example, the operator or the like may set + 0.3 m as the distortion correction information.
In this case, the space from the floor 803a to the floor 803 in FIG. 14B, that is, the space at a height of +0.3 m from the floor 803 is the "virtual floor".

Further, for example, the operator or the like may set the distortion correction information to −0.3 m.
In this case, the space from floor 803 to floor 803b in FIG. 14B, that is, the space at a height of -0.3 from floor 803 is the "virtual floor".

Based on the above concept, the virtual floor setting unit 703 sets the "virtual floor" based on the distortion correction information set in advance by the operator or the like and stored in the distortion correction information storage unit 90. Specifically, the operator or the like selects the grid corresponding to the “floor” among the grids corresponding to the points of the point cloud data 17 obtained by scanning the field of view of the three-dimensional laser scanner 10 in advance. Set the height to raise or lower the floor in. The operator or the like may appropriately set the height for raising or lowering the floor so that the floor has a desired height that can be regarded as a flat surface according to the degree of unevenness of the floor.

As described above, according to the second embodiment, the virtual floor whose floor height is corrected is set based on the strain correction information for correcting the floor height, and the three-dimensional laser scanner 10 is used to perform the operation. A virtual floor setting unit 703 that calculates the distance to the virtual floor and defines it as floor distance information is further provided, and the correction unit 702 uses the floor distance information defined by the virtual floor setting unit 703 for the current distance data and the comparison distance data. Based on this, the distance data is corrected so that the object 201, which should not exist, is not erroneously recognized, and the floor is not erroneously recognized as the object 201 due to the unevenness of the floor. .. As a result, even when the floor is not flat, the recognition accuracy of the object existing in the monitoring area is further improved without erroneously recognizing the floor as the object 201 and erroneously recognizing the object 201 that should not exist. Can be improved.

In the present invention, within the scope of the invention, it is possible to freely combine each embodiment, modify any component of each embodiment, or omit any component in each embodiment. ..

10 3D laser scanner, 11 laser light emitting unit, 12 laser light pulse, 13 dispersion mechanism, 14 dispersed laser light pulse, 15 laser reflected light, 16 laser light receiving unit, 17 point group data, 20 current data calculation unit, 21 current data Storage unit, 30 Comparison data calculation unit, 31 Comparison data storage unit, 40 Change area extraction unit, 50 Recognition processing unit, 60 Notification processing unit, 70, 70a Floor correction unit, 80 Floor-related information storage unit, 90 Distortion correction information storage Unit, 100, 100a monitoring device, 200 background, 201 object, 701 distance acquisition unit, 702 correction unit, 703 virtual floor setting unit, 801 target A, 802 target B, 803, 803a, 803b floor, 804 blank grid, 1201 Processing circuit, 1202 HDD, 1203 input interface device, 1204 output interface device, 1205 memory, 1206 CPU, 8031 convex part, 8032 concave part.

Claims (5)

From the measurement result of the 3D laser scanner that measured the monitoring area, the current data calculation unit that acquires the distance data to the object existing in the monitoring area and converts it into the current distance data.
A comparison data calculation unit that acquires the past distance data from the measurement result and converts it into comparison distance data.
With respect to the current distance data and the comparative distance data, a correction unit that corrects the distance data based on the floor distance information in which the distance from the three-dimensional laser scanner to the floor is defined, and a correction unit.
The change area extraction unit that calculates the difference value between the corrected current distance data obtained by correcting the distance data and the corrected comparative distance data, and extracts the area where the difference value is equal to or greater than the threshold value as the change area. Monitoring device with and. The correction unit
The monitoring device according to claim 1, wherein if the distance based on the distance data is larger than the distance based on the floor distance information, the distance data is corrected for the current distance data and the comparative distance data. The correction unit
The monitoring device according to claim 1 or 2, wherein the distance data is replaced with the floor distance information. The correction unit
The monitoring device according to claim 1 or 2, wherein the distance data is replaced with infinity. Based on the strain correction information for correcting the height of the floor, the virtual floor with the corrected floor height is set, and the distance from the three-dimensional laser scanner to the virtual floor is calculated to obtain the floor distance. It also has a virtual floor setting unit that is defined as information.
The correction unit
One of claims 1 to 4, wherein the distance data is corrected based on the floor distance information defined by the virtual floor setting unit with respect to the current distance data and the comparative distance data. The monitoring device described.

Images