WO2025215776A1 - Person detecting device - Google Patents

Abstract

In order to make it possible to identify the position of an object and suppress an increase in cost and device size, this person detecting device comprises a plurality of sensor units that are attached in a position higher than a reference surface and that detect an object that has entered a unit zone extending obliquely downward, and a determining unit that determines whether or not a person has entered a detection area formed by the unit zones, on the basis of detection signals from each sensor unit, wherein: a plurality of first sensor units and a single second sensor unit are provided as the sensor units; the distal edges of first projection regions, in which the unit zones of each first sensor unit are projected onto the reference surface when viewed from above, are set so as to be located further away than the distal edge of a second projection region, in which the unit zone of the second sensor unit is projected onto the reference surface, such that the first projection regions are arranged in the left-right direction and the second projection region overlaps each first projection region; and the determining unit performs a computation using the values of the detection signals of the first sensor units and the second sensor unit to identify the position of the object.

Description

Human detection device

The present invention relates to a human detection device that detects people who enter a specified detection area.

Patent Document 1 describes a human detection device that has three object-detecting detectors and detects people who enter a specified detection area. This human detection device outputs a human body detection signal indicating that a person has been detected when any one of the three detectors detects an object.

Patent Publication No. 2010-071761

However, the above-mentioned human detection device cannot determine the position within the detection area of an object that has entered the detection area.

The present invention was made to solve the above problems, and its intended purpose is to provide a human detection device that can identify the position of an object that has entered the detection area, while preventing increases in manufacturing costs and the size of the device.

In other words, the present invention has the following configuration:

[1]
a plurality of sensor units attached at a position higher than a reference plane, forming a unit zone extending obliquely downward, and detecting an object entering the unit zone;
a determination unit that determines whether or not a person has entered a detection area formed by the unit zones of each of the sensor units based on a detection signal from each of the sensor units,
The sensor units include a plurality of first sensor units and a single second sensor unit,
first projection areas, which are obtained by projecting the unit zones of the first sensor units onto the reference surface when viewed from above, are set to be aligned in the left-right direction;
a second projection area obtained by projecting the unit zone of the second sensor unit onto the reference surface as viewed from above is set to overlap with each of the first projection areas;
a leading edge of the first projection area is set to be located farther away than a leading edge of the second projection area,
A human detection device characterized in that the judgment unit calculates the value of the detection signal from the first sensor unit and the value of the detection signal from the second sensor unit, and identifies the object detection position in the detection area.

In the present invention configured in this manner, multiple first projection areas are lined up in the left-right direction on the side farther from the leading edge of the second projection area, and a single second projection area is divided into multiple regions lined up in the left-right direction by the overlapping first projection areas on the side closer to the leading edge of the second projection area. This allows the detection area to be divided into regions lined up in a matrix, and by performing a logical AND operation on the detection signals of the first sensor unit and the second sensor unit, it is possible to identify which of the matrix-divided regions an object has entered. As a result, with the present invention, the detection area can be divided into more regions than the number of sensor units, making it possible to more precisely identify the detected position of an object that has entered the detection area while suppressing an increase in the number of sensor units and thereby preventing an increase in manufacturing costs or an increase in the size of the device.

[2]
The determination unit
When a detection signal indicating that an object has been detected is received from both the first sensor unit and the second sensor unit, it is determined that an object has entered an area where the first projection area and the second projection area overlap,
A human detection device as described in [1], which, when receiving a detection signal indicating that an object has been detected from only the first sensor unit, determines that an object has entered an area of the first projection area that does not overlap with the second projection area.
The configuration [2] is a specific example of the arithmetic processing of the detection signals by the determination unit. By calculating the logical product of the values of the detection signals received from both the first sensor unit and the second sensor unit, which indicate whether an object has been detected, the detected position of the object can be identified through simple calculations.

[3]
the second projection area is set to have an outer area extending outward from a first projection area located at the left end or the right end of each of the first projection areas,
The determination unit
The human detection device according to [1], which determines that an object has entered the outer area when a detection signal indicating that an object has been detected is received from only the second sensor unit.
With this configuration, it is possible to further divide the detection area into more areas by setting up an area that is detected only by the second sensor unit within the detection area, thereby making it possible to identify the detected position of an object that has entered the detection area in more detail while suppressing an increase in the number of sensor units.

[4]
The first projection areas are arranged so as to partially overlap each other, and when the judgment unit receives a detection signal from two of the first sensor units indicating that an object has been detected, it judges that an object has entered the area where the first projection areas overlap. [1] A human detection device as described in
With this configuration, it is possible to set areas that are detected by two first sensor units within the detection area, thereby dividing the detection area into even more areas.

[5]
the sensor unit includes a PIR element and an optical member that defines the unit zone, which is a range of infrared light incident on the PIR element;
the optical member has a plurality of lenses arranged side by side, and divided zones, which are infrared incidence ranges defined by the respective lenses, are arranged side by side when viewed from above, forming the unit zones;
A human detection device as described in [1], wherein the number of lenses defining the unit zone of the first sensor unit is the same as the number of lenses of the second sensor unit that define the area of the unit zone of the second sensor unit that overlaps with the unit zone of the first sensor unit when viewed from above.
With this configuration, since the first sensor unit and the second sensor unit have the same number of lenses, it is possible to align and overlap the divided zones of these two sensor units, which makes it easier to align the timing of the detection signals output from the first sensor unit and the second sensor unit, making it easier to determine whether the detection signals represent the same object.

[6]
The human detection device described in [1] further comprises an intrusion count suggestion data output unit that generates position-specific intrusion count suggestion data that can grasp the number of times an object has intruded into each object detection position identified by the judgment unit, and transmits this to other devices such as a display.
With this configuration, the number of times an object has intruded into each object detection position can be ascertained using the position-specific intrusion count suggestion data, and therefore, if the object detection position has an intrusion count exceeding a considerable number, it is assumed that there is some factor causing a false alarm, and object detection at that object detection position can be stopped or the object detection level can be adjusted to reduce false alarms.

With this configuration, the present invention can divide the detection area into more regions than the number of sensor units used, making it possible to provide a human detection device that can identify the position of an object that has entered the detection area while preventing increases in manufacturing costs and the device size.

1 is an overall schematic diagram of a human detection device according to an embodiment of the present invention; FIG. 2 is a functional block diagram of the human detection device according to the embodiment. FIG. 2 is a schematic diagram of the internal structure of the human detection device according to the embodiment, as viewed from above. FIG. 2 is a schematic diagram of a circuit board of the human detection device of the embodiment as viewed from the front. 5 is a schematic diagram of a detection area viewed from the left and right in the embodiment; FIG. FIG. 4 is a schematic diagram of a detection area viewed from above in the embodiment. FIG. 3 is a schematic diagram showing sections set within a detection area in the embodiment. 10 is a table showing the relationship between projection areas and sections in the embodiment. FIG. 4 is a schematic diagram of unit zones and divided zones as viewed from above in the embodiment. 3 is a truth table of a logic function used by the determination unit of the embodiment; FIG. 11 is a schematic diagram of a detection area viewed from above in the second embodiment. FIG. 10 is a schematic diagram showing sections set within a detection area in the second embodiment. 10 is a table showing the relationship between projection areas and sections in the second embodiment. FIG. 11 is a schematic diagram of a detection area viewed from above in the third embodiment. FIG. 11 is a schematic diagram showing sections set within a detection area in the third embodiment. 11 is a table showing the relationship between projection areas and sections in the third embodiment. FIG. 11 is a schematic diagram of a circuit board of a human detection device according to a third embodiment, as viewed from the front. FIG. 10 is a functional block diagram of a human detection device according to a fourth embodiment. FIG. 20 is a schematic diagram of a detection area viewed from the left and right in the sixth embodiment.

100... Human detection device H... Housing FC... Cover S... Board 1... First sensor unit 11... First infrared sensor 12... First optical member 2... Second sensor unit 21... Second infrared sensor 22... Second optical member 3... Determination unit 4... Intrusion count suggestion data output unit X... Detection areas A to C... First projection area D... Second projection area

The first embodiment of the human detection device according to the present invention will be described below with reference to the drawings.

[First embodiment]
1. Overall Configuration The human detection device of this embodiment is used in an intrusion detection system that detects and issues an alarm when a suspicious person intrudes into a predetermined detection area, for example.

As shown in Figures 1 to 3, this human detection device is mounted at a position higher than a reference plane, and comprises a plurality of first sensor units 1 and a single second sensor unit 2 that form unit zones extending diagonally downward and detect objects that enter these unit zones, and a determination unit 3 that determines whether a human has entered detection area X based on the detection signals of each of the sensor units 1 and 2. The reference plane is, for example, the ground or floor surface of the location where this human detection device 100 is installed, or a surface parallel to the ground or floor surface.

The sensor units 1 and 2 are all installed in one location, and here they are housed together with the determination unit 3 in a common housing H. As shown in Figure 1, the housing H here is a vertically elongated pillar that is attached to a wall, pillar, ceiling, etc. with its front surface facing the detection area X. The mounting height of the housing H is set to, for example, approximately 0.5 to 4.0 m from the reference plane.

The up-down direction is defined as being either up or down in the vertical direction when viewed from the human detection device 100, the front-to-back direction is defined as the direction toward the center of the detection area X when viewed from the human detection device 100, and the direction perpendicular to the up-down direction and the front-to-back direction is defined as the left-to-right direction.

2. Device Configuration 2-1. First Sensor Unit 1
As shown in Figure 2, each first sensor unit 1 has a first infrared sensor 11, a first optical member 12 that defines a first unit zone, which is the range of infrared light that enters the first infrared sensor 11, and a first detection circuit that outputs a detection signal based on the output signal of the first infrared sensor 11.

In this embodiment, three first sensor units 1 are provided. The first unit zones of these three first sensor units are set to face in different directions in the left-right direction. Here, when distinguishing between the three first sensor units 1, they are designated by the symbols 1a, 1b, and 1c.

2-1-1. First infrared sensor 11
3(a) and 3(b), the first infrared sensor 11 is a passive infrared sensor that detects infrared rays emitted from an object, and in this case is a pyroelectric dual type sensor with two PIR elements mounted in a single can package. The first infrared sensor 11 detects fluctuations in the incident infrared rays and outputs an analog output signal indicating the amount of fluctuation.

The first infrared sensor 11 is mounted on a circuit board S housed within the housing H with its sensor surface facing forward. Here, the first infrared sensors 11 of the three first sensor units 1 are mounted on the circuit board S in a vertical line. The circuit board S here is a so-called PCB, and is arranged so that the mounting surface of the first infrared sensor 11 faces forward.

2-1-2. First optical member 12
3( a) and 3(b), the first optical member 12 of this embodiment is a first lens set consisting of a plurality of lenses L. This first lens set 12 is formed integrally with a cover FC that forms the front surface of the housing H. The cover FC is disposed opposite the infrared sensor mounting surface of the substrate S, and is provided to cover the substrate S.

A first lens set 12 is provided for each of the multiple first sensor units 1, and each first lens set 12 is provided so as to face the sensor surface of the first infrared sensor 11 of the same first sensor unit 1 from front to back. In this embodiment, three first lens sets 12 are provided on the cover FC in a vertically aligned manner to match the three vertically aligned first infrared sensors 11.

The first lens sets 12 of each first sensor unit 1 are offset left and right so as not to overlap when viewing the cover FC (or housing H) from above.

It is advisable to provide a shielding member (not shown) between adjacent lens sets in the vertical direction to block infrared rays. For example, by providing a horizontal, plate-shaped shielding member on the inner wall of the housing H, it is possible to prevent infrared rays that pass through the lens set of one sensor unit from entering the infrared sensors of other sensor units.

The lenses L, which are Fresnel lenses in this example, focus infrared light from within the detection area X onto each infrared sensor. Each lens L is connected to other lenses L that make up the same lens set, but they may also be spaced apart.

As shown in Figure 3(b), the multiple lenses L that make up each first lens set 12 are arranged side by side at the same height when viewing the housing H from the front. Each first lens set 12 is composed of three lenses L. Note that the number of lenses that make up each first lens set 12 may differ from each other.

The first detection circuit is formed on the substrate S, for example, and compares the value of the analog output signal received from the first infrared sensor 11 with a predetermined threshold, and outputs a detection signal, which is a digital output signal having a value of 1 or 0 depending on the magnitude of the comparison. The detection circuit here outputs a detection signal that indicates a value of 1 when an object is detected, and outputs a detection signal that indicates a value of 0 when the detection signal does not detect an object.

Each first detection circuit is provided for each first sensor unit 1, and outputs an individual detection signal based on the output signal received from the corresponding first infrared sensor 11.

2-2. Second sensor unit 2
As shown in Figure 2, the second sensor unit 2 has a second infrared sensor 21, a second optical member 22 that defines a second unit zone, which is the range of infrared light that enters the second infrared sensor 21, and a second detection circuit (not shown) that outputs a detection signal based on the output signal of the second infrared sensor 21.

In this embodiment, the second sensor unit 2 is configured to have a shorter detection distance than the first sensor unit 1, and is capable of detecting objects located at a closer distance than the first sensor unit 1.

2-2-1. Second infrared sensor 21
The second infrared sensor 21 is a pyroelectric dual type infrared sensor, similar to the first infrared sensor 11, and detects fluctuations in incident infrared light and outputs an analog output signal indicating the amount of fluctuation.

As shown in Figures 3(a) and 3(b), the second infrared sensor 21 is mounted on the substrate S with its sensor surface facing forward. In this example, it is positioned below the three first infrared sensors 11 that are lined up vertically, resulting in four infrared sensors 11, 21 lined up vertically.

2-2-2. Second optical member 22
2(a) and 2(b), the second optical member 22 of this embodiment is a second lens set consisting of a plurality of lenses L. Like the first lens set 12, this second lens set 22 is formed integrally with the cover FC.

The second lens sets 22 are positioned so that they overlap with each of the first lens sets 12 when the cover FC (or the housing H) is viewed from above.

As shown in Figure 3(b), the multiple lenses L that make up the second lens set 22 are arranged side by side at the same height when viewing the housing H from the front. Each second lens set 22 is composed of nine lenses L.

The second detection circuit is formed on the substrate S, for example, and compares the value of the analog output signal received from the second infrared sensor 21 with a predetermined threshold, and outputs a detection signal, which is a digital output signal having a value of 1 or 0 depending on the magnitude of the comparison. The detection circuit here outputs a detection signal indicating a value of 1 when an object is detected, and outputs a detection signal indicating a value of 0 when the detection signal does not detect an object.

2-3. Judgment part 3
The determination unit 3 is physically a computer (not shown) housed in, for example, the housing H. This computer is equipped with a CPU, memory, an I/O interface, a communication interface, etc., and performs the function of the determination unit 3, which determines whether or not a person has entered the detection area X, by operating the CPU and peripheral devices in cooperation with each other in accordance with a predetermined program stored in the memory.

Specifically, the determination unit 3 identifies the position in the detection area X where an object is detected (hereinafter referred to as the object detection position) based on the detection signals received from each sensor unit 1, 2, and determines whether a person has entered the detection area X.

The object detection position is determined by performing a logical operation on the value of the detection signal from the first sensor unit 1 and the value of the detection signal from the second sensor unit 2. For example, if a detection signal indicating a value of 1 is received from both the first sensor unit 1 and the second sensor unit 2, the area detected by both sensor units 1 and 2 is determined as the object detection position, and if a detection signal having the value of 1 is received only from the first sensor unit 1, the area detected only by the first sensor unit 1 is determined as the object detection position.

To identify the object detection position, the detection signal of the first sensor unit 1 and the detection signal of the second sensor unit 2, both of which are generated by the same object, are used. Specifically, the object detection position is identified using the detection signals of each sensor unit 1, 2 received by the judgment unit 3 within a predetermined period. Here, the predetermined period is determined based on, for example, the time it takes for a person to cross a unit zone. This period should be set with a width large enough to allow for errors that may occur due to differences in the arrangement of the unit zones of each sensor unit 1, 2 and variations in optical components or circuits. The judgment unit 3 may also identify the object detection position using the detection signals generated within the predetermined period.

If the determination unit 3 determines that a person has entered the detection area X, it outputs a human detection signal indicating this. In this embodiment, the human detection signal is linked to an object detection position that indicates the detected position of the object that generated the human detection signal.

3. Detection area X
The detection area X of the human detection device 100 is formed by combining a plurality of first unit zones and a single second unit zone, as shown in Figures 4 to 6. The detection area X of the human detection device 100 according to the present invention will be described in detail below with reference to Figures 4 to 6.

3-1 Unit Zones Fig. 4 is a schematic diagram showing the relationship between the first unit zone and the second unit zone in the detection area X as viewed from the left and right.
As described above, each unit zone is formed to extend diagonally downward from the sensor units 1 and 2 that are attached at a position higher than the reference surface. Each unit zone extends until it intersects with the reference surface, and the detection distance of the sensor units 1 and 2 is limited by the unit zone ending at the reference surface.

The first unit zone is set to have a longer detection distance than the second unit zone. For this reason, the inclination of the first unit zone relative to the reference plane is set to be gentler than the inclination of the second unit zone relative to the reference plane. Furthermore, when viewed from above, the second unit zone is set to overlap with each of the first unit zones on the near side of the first unit zones.

In this embodiment, the three first unit zones are set to have approximately the same inclination relative to the reference plane, but this is not limited to this.

Here, in the detection area X viewed from the left and right, the first unit zone and the second unit zone are set so that they do not overlap and are lined up one above the other with no gaps between them, but the first unit zone and the second unit zone may also be set so that they overlap or are spaced apart.

5A is a schematic diagram showing the detection area X when viewed from above. The first projection areas A to C are areas where the first unit zones of the first sensor units 1a to 1c are respectively projected onto the reference surface when viewed from above, and the second projection area D is an area where the second unit zone of the second sensor unit 2 is projected onto the reference surface when viewed from above.

When viewed from above, each projection area A to D is formed in a fan shape spreading out from sensor units 1 and 2 within a horizontal angular range (called the horizontal field of view angle) defined by the optical members 12 and 22. Each projection area A to D has its base end directly below each sensor unit 1 and 2 (or housing H) on the reference plane and extends forward to the position where each unit zone intersects with the reference plane and ends. The edge of each projection area A to D farthest from the base end is called the leading edge.

The leading edges of the first projection areas A to C (hereinafter also referred to as the first leading edges) are set to be located farther from the base end than the leading edge of the second projection area D (hereinafter also referred to as the second leading edge). Here, the distance from the base end to the leading edge of the first projection areas A to C is set to, for example, twice the distance from the base end to the tip of the second projection area D.

The first projection areas A to C are set to line up in the left-right direction when viewed from above. Here, the three first projection areas A to C are spaced apart so that they do not overlap when viewed from above, but they may also be lined up without any gaps. The distance between adjacent first projection areas should be such that there is no blind spot between the two projection areas that is larger than the detection target.

The horizontal viewing angle of the second projection area D is set to be larger than the horizontal viewing angle of each of the first projection areas A to C. Here, the horizontal viewing angle of the second projection area D is set to be approximately the same as the central angle of the fan-shaped area formed by the multiple first projection areas A to C lined up side by side.

The second projection area D is set to overlap with each of the multiple first projection areas A to C. As mentioned above, because each first tip edge is set farther away than the second tip edge, the second projection area D overlaps with each of the first projection areas A to C on the base end side of each of the first projection areas A to C.

In this way, in this embodiment, an area where the first projection areas A to C and the second projection area D overlap is set on the base end side of the detection area X when viewed from above, and an area of the first projection areas A to C that does not overlap with the second projection area D is set on the tip end side. Hereinafter, areas that are distinguished in this way by the overlapping state of the first projection area and the second projection area will be referred to as sections.

3-3. Sections I to VI set in detection area X
5B is a schematic diagram showing six sections set within the detection area X as viewed from above in this embodiment. Sections I to III are sections consisting of only one of the first projection regions A to C (the non-overlapping sections), and sections IV to VI are sections consisting of one of the first projection regions A to C overlapping with the second projection region D (the overlapping sections). The table in FIG. 5C shows the combinations of sections I to VI and the projection regions A to D that make up these sections I to VI.

In this embodiment, sections I to VI divide the detection area X, as viewed from above, into a matrix pattern from front to back and left to right. Sections I to III on the base end side (or sections IV to VI on the tip end side) are horizontally arranged areas that are the same distance from each other in the front to back direction when viewed from the human detection device 100, but have different left to right arrangements. Sections I, IV, etc., which are made up of the common first projection area A, are vertically arranged areas that are different distances from each other in the front to back direction.

In this embodiment, when an object O having a predetermined height relative to the reference plane enters sections I to III, as shown in Figure 4, it is set up so that it enters only the first unit zone and is detected only by the first sensor unit 1. Also, in this embodiment, when the object O enters sections IV to VI, it enters both the first and second unit zones and is detected by both the first sensor unit 1 and the second sensor unit 2. It is not necessary to set up so that the entering object O is detected by both the first sensor unit 1 and the second sensor unit 2 throughout the entire area of each of sections IV to VI.

Specifically, in this embodiment, in sections IV to VI on the base end side, the first unit zone is set to pass below the predetermined height from the reference plane, so that an object O that enters one of sections IV to VI is detected by both the first sensor unit 1 and the second sensor unit 2. The predetermined height is set to match the height of the object to be detected, and in this case, it is set to match the height of the person being detected.

The specified height is set by adjusting the mounting height of each sensor unit 1, 2, the angular range of the unit zone, or the angle of each unit zone relative to the reference plane. Here, by mounting the human detection device 100 at a position close to the height of a person, it is configured to prevent a person from entering each unit zone throughout almost the entire detection area X.

3-4. Divided Zones Furthermore, each unit zone in this embodiment is formed by a plurality of divided zones as shown in Fig. 6. A divided zone is the angular range (infrared incident range) of infrared rays that pass through the lens and enter the infrared sensors 11 and 21, and is defined by the focal length of the lens.

When the detection area X is viewed from above, each unit zone is formed by multiple divided zones lined up on the left and right. In this embodiment, the first sensor units 1a to 1c have three lenses (the lens set described above), and the first unit zone is formed by three divided zones. The second sensor unit 2 has nine lenses, and the second unit zone is formed by nine divided zones.

In this embodiment, as shown in Figure 6, the angular range (horizontal field of view) of the divided zones when viewed from above is set to be approximately the same for the first sensor unit 1 and the second sensor unit 2.

Furthermore, when viewing the detection area X from above, in the regions where each first unit zone and each second unit zone overlap, the divided zones that form the first unit zone and the divided zones that form the second unit zone are set to overlap each other.

In this embodiment, the number of lenses defining the first unit zone is the same as the number of lenses of the second sensor unit 2 that define the area of the second unit zone that overlaps with the first unit zone, and the divided zones of each first unit zone and the divided zones of the second unit zone overlap in a one-to-one relationship. Furthermore, the two overlapping divided zones are set so that their central axes overlap each other when viewed from above.

4. Operation Hereinafter, it will be described how the human detection device 100 of this embodiment operates when an object O enters the detection area X configured as described above.

Specifically, when an object enters section I, first sensor unit 1a detects the object and outputs a detection signal with a value of 1. The other sensor units 1b, 1c, and 2 do not detect the object and therefore output detection signals with a value of 0.

In this way, when a detection signal indicating that an object has been detected is received from only the first sensor unit 1a, it is determined that the object has entered section I, which is an area of the first projection area A that does not overlap with the second projection area D. More specifically, the determination unit 3 performs a logical operation on each of the received detection signals using a predetermined logical function to identify section I as the object detection position. Here, the predetermined logical function is a four-input, six-output logical function that calculates the logical product of the detection signal values of the four sensor units 1 and 2 and determines which of the six sections I to VI the object has entered. Figure 7 is a truth table representing this logical function.

Furthermore, when an object enters section IV, the first sensor unit 1a and the second sensor unit 2 output detection signals having a value of 1, and the other sensor units 1b and 1c output detection signals having a value of 0.
In this way, when detection signals indicating that an object has been detected are received from both the first sensor unit 1a and the second sensor unit 2, the determination unit 3 determines that an object has entered section IV, which is the area where the first projection area A and the second projection area D overlap. More specifically, the determination unit 3 performs a logical operation on each of the received detection signals using the logical function, and identifies section IV as the object detection position.

If the determination unit 3 determines that an object has entered any of the sections I to VI, that is, if it has identified the object's detection position, it determines that a person has entered the detection area X and outputs a human detection signal indicating this to, for example, a security system. Furthermore, the determination unit 3 outputs object detection position information indicating the section into which the object has entered, linked to the human detection signal. Note that the determination unit 3 may also output an object detection position signal indicating the object detection position separately from the human detection signal.

If no object has entered any of the sections, each sensor unit 1, 2 outputs a detection signal with a value of 0. The judgment unit 3 receives these detection signals and performs a logical operation using the logic function to determine that no object has been detected in the detection area X.

5. Effects With the human detection device 100 of the first embodiment configured as described above, the detection area X can be divided into more sections than the number of sensor units 1, 2 used, and it is possible to more precisely identify the detected position of an object that has entered the detection area X while suppressing an increase in the number of sensor units 1, 2, thereby suppressing an increase in manufacturing costs or an increase in the size of the device. In this embodiment, the four sensor units 1, 2 divide the detection area into six sections.

The detected position of an object can be identified by a simple logical operation: calculating the logical product of the values of the detection signals received from both the first sensor unit 1 and the second sensor unit 2.

Since object detection position information indicating the section into which the object has entered is output, it is possible to count the number of times an object has entered each section, for example, and this can be useful for masking detection area X and adjusting the thresholds of each sensor unit.

Because the detection area X is divided into sections arranged in a matrix from front to back and left to right, when adjusting the detection area X using masking or other methods, it is easier to imagine what the detection area will look like after adjustment, making area adjustment simple.

Because the divided zones of the first sensor unit 1 and the second sensor unit 2 overlap, the timing of the detection signals output from the first sensor unit 1 and the second sensor unit 2 that detect the same object can be aligned. This simplifies signal processing in the determination unit 3.

Second Embodiment
8A, the human detection device 100 of the second embodiment differs from the first embodiment in that, when the detection area X is viewed from above, the second projection area D is set to have an outer area that extends outward from the first projection area C located at the right end of the first projection areas A to C. Note that the outer area may extend outward from the first projection area A located at the left end, or may extend outward from each of the first projection areas A and C located at the left and right ends.

Specifically, the horizontal viewing angle of the second projection area D in the second embodiment is set to be larger than the central angle of the fan-shaped area formed by the multiple first unit zones lined up on the left and right, and the second projection area D extends outward (to the right) from the rightmost first unit zone in the detection area X, forming an outer area.

By setting projection areas A to D in this manner, as shown in Figures 8(a) to (c), the detection area X viewed from above includes an area (sections I to III) made up only of the first projection areas A to C, an area (sections IV to VI) made up of the overlapping first projection areas A to C and the second projection area D, and an outer area (section VII) made up only of the second projection area D. In this embodiment, the detection area X is divided into seven sections by the four sensor units 1 and 2.

In the second embodiment, when the determination unit 3 receives a detection signal indicating that an object has been detected from only the second sensor unit 2, it determines that an object has entered the outer region of the second projection region D of the second sensor unit 2. Here, when a detection signal indicating that an object has been detected is received from only the second sensor unit 2, it determines that an object has entered section VII, and identifies this section VII as the object detection position.

With this configuration, the detection area X can be divided into smaller areas without increasing the number of sensor units 1 and 2, making it possible to more precisely identify the detection position of an object that has entered the detection area X.

[Third embodiment]
The human detection device 100 of the third embodiment differs from the previous embodiments in that, as shown in Figure 9(a), when the detection area X is viewed from above, the first projection areas A and B are arranged so that they partially overlap each other.

Specifically, as shown in FIG. 10, the human detection device 100 of the third embodiment includes two first sensor units 1a, 1b and a single second sensor unit 2. The two first lens sets 12 are arranged so as to overlap each other when viewing the cover FC (or the housing H) from above, and the detection area X described above is defined.

When the detection area X of the third embodiment is viewed from above, as shown in Figure 9(a), the two first projection areas A and B arranged side by side are configured so that they partially overlap each other from their respective base ends to their respective tip ends. The second projection area D is also configured so that it overlaps with the base ends of each of the first projection areas A and B.

By setting projection areas A, B, and D in this manner, as shown in Figures 10(a) to (c), the detection area X viewed from above includes areas consisting of only one of the first projection areas A and B (sections I and III), areas consisting of one of the first projection areas A and B overlapping with the second projection area D in a one-to-one relationship (sections IV and VI), an area where two of the first projection areas A and B overlap (section II), and an area where the area where two of the first projection areas A and B overlap is further overlapped by the second projection area D (section V). Here, the three sensor units 1a, 1b, and 2 divide the detection area X into six sections in a matrix.

The determination unit 3 of the third embodiment determines that an object has entered the area where the first projection areas A and B overlap when it receives detection signals from the two first sensor units 1a and 1b indicating that an object has been detected. Specifically, when it receives detection signals from both first sensor units 1a and 1b indicating that an object has been detected, it determines that an object has entered section II and identifies this section II as the object detection position.

Furthermore, when the determination unit 3 receives detection signals from the two first sensor units 1a, 1b indicating that an object has been detected, and also receives a detection signal from the second sensor unit 2 indicating that an object has been detected, it determines that an object has entered the area where the unit zones of these three sensor units 1a, 1b, 2 overlap. Here, when detection signals indicating that an object has been detected are received from all of the first sensor units 1a, 1b and the second sensor unit 2, it determines that an object has entered section V, and identifies this section V as the object detection position.

With this configuration, the detection area X can be divided into smaller areas without increasing the number of sensor units, making it possible to more precisely identify the detection position of an object that has entered the detection area X.

[Fourth embodiment]
As shown in Figure 11, the human detection device 100 of the fourth embodiment further includes an intrusion count suggestion data output unit 4 that generates position-specific intrusion count suggestion data that enables the number of object intrusions into each object detection position identified by the judgment unit 3 to be determined, and transmits this to other devices such as a display.
The intrusion count suggestion data output unit 4 is physically provided as a computer common to the above-mentioned determination unit 3 .

For example, when the intrusion count suggestion data output unit 4 receives an object detection position signal from the judgment unit 3 indicating the position where an object has intruded (here, one of sections I to VI), it acquires the time at which the signal was received, associates the section into which the object has intruded with the corresponding reception time, and stores this in a specified area of memory. Here, the reception history of object detection position signals for each section is stored together as log data.

The intrusion count suggestion data output unit 4 references a specified area of the memory, generates position-specific intrusion count suggestion data indicating the number of times an object has intruded into each section within a specified period, and outputs this in a format that can be read by other devices. For example, the intrusion count suggestion data output unit 4 generates table data that allows the number of times an object has intruded into each section to be ascertained, and outputs this to a display.

With this configuration, the number of object intrusions at each object detection position can be determined using the intrusion count suggestion data by position. Therefore, if the number of intrusions exceeds a certain number, it is assumed that there is some factor causing a false alarm, and object detection at that object detection position can be stopped or the object detection level adjusted to reduce false alarms.

Fifth Embodiment
The determination unit in each of the above embodiments determines that a person has entered the detection area when it identifies the detected position of an object within the detection area, and outputs a person detection signal.
In contrast, the judgment unit of the fifth embodiment determines that a person has entered the detection area when the detection position of an object is identified and the detection position is set to an alert position, and outputs a person detection signal.

For example, the determination unit references alert position data stored in advance in a specified area of memory, and if it determines that an object has entered a position corresponding to one or more alert positions indicated in the alert position data, it determines that a person has entered the detection area. The alert position data here is, for example, a binary value indicating alert or non-alert, set for each of sections I to VI that divide the detection area. The alert position data stored in a specified area of memory is held in a changeable state, and the determination unit is configured to change the alert position data automatically under specified conditions, or when it receives a change command from outside.

With this configuration, the effective detection area can be set more flexibly by designating the area within the entire detection area where you want to detect human intrusion as an alert position, and designating the remaining area as a non-alert position.

Furthermore, by changing the alert position data, the range of the effective detection area can be adjusted without physical masking. Unlike physical masking, this allows for stable area adjustment regardless of the skill of the person adjusting the detection area. For example, because it is not physical area adjustment, an operator can remotely set areas with a high number of object intrusions as non-alert positions through input from an input device configured to communicate with the human detection device.

Sixth Embodiment
In the sixth embodiment, as shown in FIG. 12, the human detection device 100 is installed at a position higher than the height of a person (here, at a position about twice the height), and each unit zone at the base end of the detection area X is set to pass above a predetermined height.

As a result, the area where the first projection area and the second projection area overlap is further divided into an area where an intruder enters both the first unit zone and the second unit zone, an area where an intruder enters only the second unit zone, and an area where an intruder does not enter any unit zone. This is advantageous when you want to form a detection area at a location away from the human detection device 100.

[Other embodiments]
The determination by the determination unit as to whether a person has entered the detection area may be performed independently of the determination unit's identification of the object detection position. For example, the determination unit may determine that a person has entered the detection area when it receives a detection signal indicating that an object has been detected from any one of the sensor units. Independently of this determination, the determination unit may calculate the values of the detection signals received from each sensor unit to identify the detection position of the object entering the detection area.

The detection signals used by the determination unit to detect people and identify object detection positions may be analog output signals indicating the amount of fluctuation in the incident infrared light detected by each infrared sensor, and may be any type of detection signal as long as it calculates the detection signals from both the first and second sensor units to identify the object detection position.

For example, if the detection signal of a certain first sensor unit and the detection signal of a certain second sensor unit indicate a value equal to or greater than a predetermined threshold, and the ratio of the values indicated by these two detection signals is within a predetermined range, the determination unit may identify the area where the first projection area of the first sensor unit and the second projection area of the second sensor unit overlap as the object detection position.

Furthermore, the determination unit may identify, as the object detection position, an area where the first projection areas of two or more first sensor units overlap, based on the analog output signals of those two or more first sensor units.

A human detection device using a pyroelectric PIR element has difficulty detecting the approach of an object moving straight toward the human detection device within the detection area.
Therefore, the determination unit may determine whether an object has entered the overlapping area between the first projection area and the second projection area based on a detection signal indicating that an object has been detected by the first sensor unit and a detection signal indicating that an object has been detected by the second sensor unit received a predetermined time after the generation of the first detection signal. Here, the predetermined time corresponds to the time it takes for an object that has entered the first projection area to enter the second projection area, and is calculated based on, for example, the distance from the first leading edge to the second leading edge.
In this case, in a human detection device using a pyroelectric PIR element, if an object enters the first projection area and continues to move straight toward the human detection device within the detection area, it can be detected when it enters the second projection area, and the approach of the object can be determined.

In the above embodiments, the number of first sensor units was two or three, but it may be four or more, as long as there is more than one. In the present invention, by overlapping each of the multiple first projection areas with a single second projection area, it is possible to set an area of at least "the number of first sensor units x 2" within the detection area.

A human detection device may be provided with multiple sensor unit groups, each consisting of multiple first sensor units and a single second sensor unit that forms a second projection area that overlaps with the first projection area.

The arrangement of the infrared sensors or optical components in each sensor unit is not limited to that described in the above embodiments. Furthermore, the configuration of the infrared sensors and optical components may differ between sensor units.

The infrared sensor may be a single type or quad type, or may be a PIR sensor such as a thermopile, or may be an AIR sensor having an irradiator that irradiates an infrared LED and a receiver that receives the reflected infrared LED light.

The unit zone does not have to be divided into multiple divided zones. In this case, each optical element may be a single lens.

The optical element may be composed of a mirror, or may be composed of a combination of a lens and a mirror.

The human detection device in each of the above embodiments is configured with a sensor unit and a computer functioning as a judgment unit, etc., located within a common housing, but the physical configuration of the human detection device according to the present invention is not limited to this. Furthermore, the physical locations of each component element are not limited to the locations shown in each embodiment.

For example, the sensor unit may be equipped with an analog circuit including a comparator, an AD converter, and a digital electrical circuit such as a computer or PLD, which may perform the functions of the detection circuit, and this computer may be common to the judgment unit. Furthermore, the sensor units do not need to be located in the same housing, as long as they are arranged relatively close together.

Some or all of the functions of the aforementioned judgment unit or intrusion count suggestion data output unit may be provided separately from the sensor unit and performed by an information processing device that can communicate unilaterally or mutually with the sensor unit. The information processing device is, for example, a computer equipped with a CPU, memory, input/output interfaces such as a display, a communication interface, etc. In this case, when building a security system equipped with multiple human detection devices, a common information processing device can be used to integrate and process the multiple human detection devices.

According to the present invention, it is possible to provide a human detection device that can identify the position of an object that has entered a detection area, while suppressing increases in manufacturing costs and size of the device.

Claims (6)

a plurality of sensor units attached at a position higher than a reference plane, forming a unit zone extending obliquely downward, and detecting an object entering the unit zone;
a determination unit that determines whether or not a person has entered a detection area formed by the unit zones of each of the sensor units based on a detection signal from each of the sensor units,
The sensor units include a plurality of first sensor units and a single second sensor unit,
first projection areas, which are obtained by projecting the unit zones of the first sensor units onto the reference surface when viewed from above, are set to be aligned in the left-right direction;
a second projection area obtained by projecting the unit zone of the second sensor unit onto the reference surface as viewed from above is set to overlap with each of the first projection areas;
a leading edge of the first projection area is set to be located farther away than a leading edge of the second projection area,
A human detection device characterized in that the judgment unit calculates the value of the detection signal from the first sensor unit and the value of the detection signal from the second sensor unit, and identifies the object detection position in the detection area. The determination unit
When a detection signal indicating that an object has been detected is received from both the first sensor unit and the second sensor unit, it is determined that an object has entered an area where the first projection area and the second projection area overlap,
A human detection device as described in claim 1, which, when receiving a detection signal indicating that an object has been detected from only the first sensor unit, determines that an object has entered an area of the first projection area that does not overlap with the second projection area. the second projection area is set to have an outer area extending outward from a first projection area located at the left end or the right end of each of the first projection areas,
The determination unit
2. The human detection device according to claim 1, wherein the device determines that an object has entered the outer area when a detection signal indicating that an object has been detected is received from only the second sensor unit. The human detection device of claim 1, wherein the first projection areas are arranged so as to partially overlap each other, and the determination unit determines that an object has entered the area where the first projection areas overlap when it receives detection signals from two of the first sensor units indicating that an object has been detected. the sensor unit includes a PIR element and an optical member that defines the unit zone, which is a range of infrared light incident on the PIR element;
the optical member has a plurality of lenses arranged side by side, and divided zones, which are infrared incidence ranges defined by the respective lenses, are arranged side by side when viewed from above, forming the unit zones;
A human detection device as described in claim 1, wherein the number of lenses defining the unit zone of the first sensor unit is the same as the number of lenses of the second sensor unit that define the area of the unit zone of the second sensor unit that overlaps with the unit zone of the first sensor unit when viewed from above. The human detection device of claim 1 further comprises an intrusion count suggestion data output unit that generates position-specific intrusion count suggestion data that can grasp the number of times an object has intruded into each object detection position identified by the judgment unit, and transmits this to other devices such as a display.