Person detecting device

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

[0001] The present invention relates to a human detection device that detects a person who has entered a predetermined detection area.

[0002] Patent Document 1 describes a human detection device that has three object detectors and detects a person who enters a predetermined 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.

[0003] Patent Publication No. 2010-071761

[0004] However, the above-described human detection device cannot identify the position within the detection area of ​​an object that has entered the detection area.

[0005] The present invention has been 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 a detection area while preventing increases in manufacturing costs and the size of the device.

[0006] That is, the present invention has the following configuration.

[0007] [1] A human detection device comprising: a plurality of sensor units that are attached at a position higher than a reference surface, that form unit zones that extend diagonally downward, and that detect objects that enter these unit zones; and a judgment unit that judges whether a human has entered a detection area formed by the unit zones of each of the sensor units based on detection signals from each of the sensor units, wherein the sensor units include a plurality of first sensor units and a single second sensor unit; first projection areas, formed by projecting the unit zones of each of the first sensor units onto the reference surface as viewed from above, are set to be aligned in the left-right direction; second projection areas, formed by projecting the unit zones of the second sensor unit onto the reference surface as viewed from above, are set to overlap with each of the first projection areas; and a leading edge of the first projection area is set to be located farther away than a leading edge of the second projection area; and the judgment unit calculates values ​​of the detection signals from the first sensor units and the second sensor units, and identifies the object detection position in the detection area.

[0008] In the present invention configured as described above, a plurality of first projection areas are arranged 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 a plurality of regions arranged in the left-right direction by the overlapping first projection areas on the side closer to the leading edge of the second projection area, thereby dividing the detection area into regions arranged in the left-right direction, and further, by performing, for example, a logical AND operation on the detection signals of the first sensor unit and the second sensor unit, it is possible to identify into which of the regions divided in the matrix an object has entered. As a result, with the present invention, it is possible to divide the detection area into more regions than the number of sensor units, and it is 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 and thereby suppressing an increase in manufacturing costs or an increase in the size of the device.

[0009] [2] The human detection device according to [1], wherein the determination unit determines that an object has entered an area where the first projection area and the second projection area overlap when it receives detection signals indicating that an object has been detected from both the first sensor unit and the second sensor unit, and determines that an object has entered an area of ​​the first projection area that does not overlap with the second projection area when it receives a detection signal indicating that an object has been detected from only the first sensor unit. The configuration of [2] embodies 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, indicating whether an object has been detected, the detected position of the object can be identified by simple calculation processing.

[0010] [3] The human detection device according to [1], wherein the second projection area is set to have an outer area extending outward from a first projection area located at the left or right end of each of the first projection areas, and the determination unit 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 set an area within the detection area that is detected only by the second sensor unit, thereby dividing the detection area into even more areas. This makes it possible to more precisely identify the detected position of an object that has entered the detection area while minimizing an increase in the number of sensor units.

[0011] [4] The human detection device according to [1], wherein the first projection areas are arranged to partially overlap each other, and when the determination unit receives detection signals indicating that an object has been detected from the two first sensor units, it determines that an object has entered the area where the first projection areas overlap. With this configuration, it is possible to set areas within the detection area that are detected by the two first sensor units, and divide the detection area into even more areas.

[0012] [5] The human detection device according to [1], wherein the sensor unit includes a PIR element and an optical element defining the unit zone, which is the range of infrared light incident on the PIR element. The optical element has a plurality of lenses arranged side by side, and the divided zones, which are the infrared light incident ranges defined by each lens, are arranged side by side as viewed from above to form the unit zone. 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, the first sensor unit and the second sensor unit have the same number of lenses, which makes it possible to align the sizes of the divided zones of these two sensor units and overlap them. This 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 each detection signal represents the detection of the same object.

[0013] [6] The human detection device according to [1], further comprising an intrusion count suggestion data output unit that generates position-specific intrusion count suggestion data that enables the number of object intrusions into each object detection position identified by the determination unit to be ascertained, and transmits this to another device such as a display. With this configuration, the number of object intrusions into each object detection position can be ascertained from the position-specific intrusion count suggestion data, so that if the object detection position has a number of intrusions exceeding a considerable number, it is determined 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.

[0014] According to the present invention configured in this manner, the detection area can be divided 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 also preventing increases in manufacturing costs and the size of the device.

[0015] 1 is a schematic overall diagram of a human detection device according to an embodiment of the present invention; a functional block diagram of the human detection device according to the same embodiment; a schematic diagram of the internal structure of the human detection device according to the same embodiment, viewed from above; a schematic diagram of the circuit board of the human detection device according to the same embodiment, viewed from the front; a schematic diagram of the detection area according to the same embodiment, viewed from the left and right direction; a schematic diagram of the detection area according to the same embodiment, viewed from above; a schematic diagram showing sections set within the detection area according to the same embodiment; a table showing the relationship between the projection area and the sections according to the same embodiment; a schematic diagram of unit zones and divided zones according to the same embodiment, viewed from above; a truth table of a logical function used by the determination unit according to the same embodiment; a schematic diagram of the detection area according to the second embodiment, viewed from above; a schematic diagram showing sections set within the detection area according to the second embodiment; a table showing the relationship between the projection area and the sections according to the second embodiment; a schematic diagram of the detection area according to the third embodiment, viewed from above; a schematic diagram showing sections set within the detection area according to the third embodiment; a table showing the relationship between the projection area and the sections according to the third embodiment; a schematic diagram of the circuit board of the human detection device according to the third embodiment, viewed from the front. 10 is a functional block diagram of a human detection device according to a fourth embodiment. FIG. 11 is a schematic diagram of a detection area according to a sixth embodiment, as viewed from the left and right.

[0016] REFERENCE SIGNS LIST 100...Human detection device H...Housing FC...Cover S...Substrate 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 section 4...Intrusion count suggestion data output section X...Detection area A to C...First projection area D...Second projection area

[0017] A first embodiment of a human detection device according to the present invention will be described below with reference to the drawings.

[0018] First Embodiment 1. Overall Configuration A human detection device according to this embodiment is used in an intrusion detection system that detects and issues an alert when a suspicious person enters a predetermined detection area, for example.

[0019] 1 to 3, this human detection device is attached at a position higher than a reference plane, and includes 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 or not a human has entered a 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.

[0020] The sensor units 1 and 2 are provided together in one place, and are housed together with the determination unit 3 in a common housing H. As shown in Fig. 1, the housing H here has a vertically long columnar shape and 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, about 0.5 to 4.0 m from the reference plane.

[0021] The up and down direction is defined as being up or down vertically when viewed from the human detection device 100, the front and back direction is defined as being the forward direction when viewed from the human detection device 100, and the direction perpendicular to the up and down direction and the front and back direction is defined as the left and right direction.

[0022] 2. Device Configuration 2-1. First Sensor Unit 1 As shown in FIG. 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 incident on 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.

[0023] 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, the three first sensor units 1 are distinguished by the symbols 1a, 1b, and 1c.

[0024] 2-1-1. First infrared sensor 11 As shown in Figures 3(a) and 3(b), the first infrared sensor 11 is a passive infrared sensor that detects infrared rays emitted from an object. In this case, it 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.

[0025] The first infrared sensor 11 is mounted on a substrate S housed in 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 substrate S so as to be aligned vertically. The substrate S here is a so-called PCB, and is arranged so that the mounting surface of the first infrared sensor 11 faces forward.

[0026] 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 constitutes 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.

[0027] A first lens set 12 is provided for each of the plurality of first sensor units 1, and each first lens set 12 is provided so as to face front to back with the sensor surface of the first infrared sensor 11 of the same first sensor unit 1. In this embodiment, three first lens sets 12 are provided on the cover FC in a vertically aligned manner to match the three first infrared sensors 11 aligned vertically.

[0028] The first lens sets 12 of the first sensor units 1 are arranged offset in the left-right direction so as not to overlap with each other when the cover FC (or the housing H) is viewed from above.

[0029] A shielding member (not shown) for blocking infrared rays may be provided between adjacent lens sets in the vertical direction. For example, by providing a plate-shaped shielding member extending in the horizontal direction on the inner wall of the housing H, infrared rays that pass through the lens set of one sensor unit can be prevented from entering the infrared sensors of other sensor units.

[0030] 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 here is connected to other lenses L that make up the same lens set, but may also be spaced apart.

[0031] As shown in Fig. 3(b) , the multiple lenses L constituting 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 constituting each first lens set 12 may differ from each other.

[0032] 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.

[0033] Each first detection circuit is provided for each first sensor unit 1 and outputs a detection signal individually based on the output signal received from the corresponding first infrared sensor 11 .

[0034] 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 incident on 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.

[0035] The second sensor unit 2 of this embodiment is configured to have a shorter detection distance than the first sensor unit 1, and is capable of detecting an object located at a closer distance than the first sensor unit 1.

[0036] 2-2-1. Second infrared sensor 21 The second infrared sensor 21, like the first infrared sensor 11, is a pyroelectric dual type infrared sensor that detects fluctuations in incident infrared light and outputs an analog output signal indicating the amount of fluctuation.

[0037] 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, the second infrared sensor 21 is disposed below the three first infrared sensors 11 arranged vertically, so that the four infrared sensors 11, 21 are arranged vertically in a line.

[0038] 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.

[0039] The second lens sets 22 are arranged at positions overlapping with the respective first lens sets 12 when the cover FC (or the housing H) is viewed from above.

[0040] 3B, the plurality of lenses L constituting the second lens set 22 are arranged side by side at the same height when viewed from the front of the housing H. Each second lens set 22 is composed of nine lenses L.

[0041] 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.

[0042] The judgment unit 3 is physically a computer (not shown) housed, for example, in the housing H. This computer is equipped with a CPU, memory, an I / O interface, a communication interface, etc., and functions as the judgment unit 3 that judges 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.

[0043] Specifically, the judgment unit 3 identifies the position where an object is detected in the detection area X (hereinafter referred to as the object detection position) based on the detection signals received from each sensor unit 1, 2, and judges whether a person has entered the detection area X.

[0044] The object detection position is identified 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, when detection signals indicating a value of 1 are received from both the first sensor unit 1 and the second sensor unit 2, the area detected by both these sensor units 1 and 2 is identified as the object detection position, and when a detection signal having the value of 1 is received from only the first sensor unit 1, the area detected by only the first sensor unit 1 is identified as the object detection position.

[0045] The object detection position is determined using the detection signals of the first sensor unit 1 and the second sensor unit 2, both of which are generated by the same object. Specifically, the determination unit 3 determines the object detection position using the detection signals of the sensor units 1 and 2 received 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 due to differences in the arrangement of the unit zones of the sensor units 1 and 2 and variations in optical components or circuits. Note that the determination unit 3 may also determine the object detection position using the detection signals generated within the predetermined period.

[0046] When 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 indicating the detection position of the object that generated the human detection signal.

[0047] 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.

[0048] 4 is a schematic diagram showing the relationship between the first and second unit zones 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, which 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.

[0049] The first unit zones are set to have a longer detection distance than the second unit zones. For this reason, the inclination of the first unit zones relative to the reference plane is set to be gentler than the inclination of the second unit zones relative to the reference plane. Furthermore, when viewed from above, the second unit zones are set to overlap with each of the first unit zones on the front side of the first unit zones.

[0050] 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 limitative.

[0051] 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 without any gaps, but the first unit zone and the second unit zone may also be set so that they overlap or are set apart.

[0052] 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.

[0053] When viewed from above, each of the projection areas A to D is formed spreading out in a fan shape from the 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 of the projection areas A to D has a base end directly below the corresponding sensor unit 1 or 2 (or housing H) on the reference plane and extends forward to a position where each unit zone intersects with the reference plane and ends. The edge of each of the projection areas A to D farthest from the base end is called the leading edge.

[0054] The leading edges of the first projection regions A to C (hereinafter also referred to as first leading edges) are set to be located farther from the base end than the leading edge of the second projection region D (hereinafter also referred to as second leading edge). Here, the distance from the base end to the leading edge of the first projection regions A to C is set to be, for example, twice the distance from the base end to the tip of the second projection region D.

[0055] The first projection areas A to C are set to be aligned in the left-right direction when viewed from above. Here, the three first projection areas A to C are aligned at a distance so as not to overlap when viewed from above, but they may also be aligned without any gaps. The distance between adjacent first projection areas is preferably such that a blind spot larger than the detection target is not formed between the two projection areas.

[0056] The horizontal viewing angle of the second projection area D is set to be larger than the horizontal viewing angles 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 plurality of first projection areas A to C arranged side by side.

[0057] The second projection region D is set so as to overlap with each of the plurality of first projection regions A to C. As described above, since each of the first tip edges is set at a position farther than the second tip edges, the second projection region D overlaps with each of the first projection regions A to C on the base end side of each of the first projection regions A to C.

[0058] In this manner, 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 manner based on the overlapping state of the first projection area and the second projection area will be referred to as sections.

[0059] 3-3. Sections I to VI Set in Detection Area X FIG. 5B is a schematic diagram showing six sections set in the detection area X as viewed from above in this embodiment. Sections I to III are areas consisting of only one of the first projection regions A to C (the non-overlapping areas), and sections IV to VI are areas consisting of one of the first projection regions A to C overlapping with the second projection region D (the overlapping areas). The table in FIG. 5C shows the combinations of each of the sections I to VI and the projection regions A to D that make up these sections I to VI.

[0060] In this embodiment, sections I to VI divide the detection area X in a matrix fashion from front to back and left to right when viewed from above. Sections I to III on the base end side (or sections IV to VI on the tip end side) are horizontally arranged regions that are the same distance from each other in the front to back direction when viewed from the human detection device 100, but are arranged differently in the left to right direction. Sections I, IV, etc., which are formed by the common first projection area A, are vertically arranged regions that are different distances from each other in the front to back direction.

[0061] In this embodiment, as shown in Fig. 4, when an object O having a predetermined height with respect to the reference plane enters one of sections I to III, it is set 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 one of sections IV to VI, it enters both the first unit zone and the second unit zone and is detected by both the first sensor unit 1 and the second sensor unit 2. Note that it is not necessary to set the object O to be 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.

[0062] 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 according to the height of the detection target, and in this case, it is set according to the height of a person who is the detection target.

[0063] The predetermined height is set by adjusting the mounting height of each sensor unit 1, 2, the angle 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, the detection area X is configured to prevent a person from entering each unit zone throughout the entire detection area X.

[0064] 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.

[0065] When the detection area X is viewed from above, each unit zone is formed by a plurality of 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 three divided zones form the first unit zone. The second sensor unit 2 has nine lenses, and the nine divided zones form the second unit zone.

[0066] In this embodiment, as shown in FIG. 6, the angular range (horizontal viewing angle) of the divided zones as viewed from above is set to be approximately the same for the first sensor unit 1 and the second sensor unit 2.

[0067] 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.

[0068] In this embodiment, the number of lenses defining a first unit zone is the same as the number of lenses of the second sensor unit 2 defining 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.

[0069] 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.

[0070] Specifically, when an object enters section I, first sensor unit 1a detects the object and outputs a detection signal having a value of 1. The other sensor units 1b, 1c, and 2 do not detect the object and therefore output detection signals having a value of 0.

[0071] 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 values ​​of the detection signals from the four sensor units 1 and 2 and identifies which of the six sections I to VI the object has entered. Figure 7 is a truth table representing this logical function.

[0072] 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, it is determined 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.

[0073] When the determination unit 3 determines that an object has entered any of the sections I to VI, that is, when it identifies the detection position of the object, 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 output an object detection position signal indicating the object detection position separately from the human detection signal.

[0074] If no object has entered any of the sections, each of the sensor units 1 and 2 outputs a detection signal having a value of 0. Upon receiving each of these detection signals, the determination unit 3 performs a logical operation using the logical function and determines that no object has been detected in the detection area X.

[0075] 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.

[0076] The detected position of the object can be identified by a simple logical operation of 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 .

[0077] Since information on the object detection position 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, which can be useful for masking the detection area X and adjusting the threshold values ​​of each sensor unit.

[0078] Since the detection area X is divided into sections arranged in a matrix in the front, rear, left and right directions, when adjusting the detection area X by masking or the like, it is easy to imagine the detection area after adjustment, and the area adjustment becomes simple.

[0079] Since the divided zones of the first sensor unit 1 and the second sensor unit 2 overlap each other, 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 synchronized, thereby simplifying the signal processing in the determination unit 3.

[0080] 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.

[0081] 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 a plurality of first unit zones lined up on the left and right, and the second projection area D extends outward (to the right) from the first unit zone located at the rightmost end in the detection area X, forming an outer area.

[0082] 8(a) to 8(c), by setting the projection regions A to D in this manner, the detection area X viewed from above includes an area (sections I to III) made up of only the first projection regions A to C, an area (sections IV to VI) made up of the first projection regions A to C overlapping with the second projection region D, and an outer area (section VII) made up of only the second projection region D. In this embodiment, the four sensor units 1 and 2 divide the detection area X into seven sections.

[0083] When the determination unit 3 of the second embodiment 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.

[0084] 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 identify the detection position of an object that has entered the detection area X in more detail.

[0085] [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.

[0086] 10, the human detection device 100 of the third embodiment includes two first sensor units 1a and 1b and a single second sensor unit 2. The two first lens sets 12 are arranged so as to overlap each other when the cover FC (or the housing H) is viewed from above, and the detection area X as described above is set.

[0087] 9A, when the detection area X of the third embodiment is viewed from above, the first projection areas A and B arranged side by side are set to partially overlap each other from the base end to the tip end, and the second projection area D is set to overlap with the base end of each of the first projection areas A and B.

[0088] 10(a) to 10(c), by setting the projection regions A, B, and D in this manner, the detection area X viewed from above includes an area (sections I and III) consisting of only one of the first projection regions A and B, an area (sections IV and VI) consisting of one of the first projection regions A and B overlapping with the second projection region D in a one-to-one relationship, an area (section II) where two of the first projection regions A and B overlap, and an area (section V) where the area where the two first projection regions A and B overlap is further overlapped with the second projection region D. Here, the three sensor units 1a, 1b, and 2 divide the detection area X into six sections in a matrix.

[0089] When the determination unit 3 of the third embodiment receives detection signals from the two first sensor units 1 a and 1 b indicating that an object has been detected, it determines that an object has entered the overlapping area of ​​the first projection areas A and B. Specifically, when the determination unit 3 receives detection signals from both the first sensor units 1 a and 1 b 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.

[0090] Furthermore, when the determination unit 3 receives detection signals indicating that an object has been detected from the two first sensor units 1a, 1b and also receives a detection signal indicating that an object has been detected from the second sensor unit 2, 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.

[0091] With this configuration, the detection area X can be divided into smaller areas without increasing the number of sensor units, making it possible to identify the detection position of an object that has entered the detection area X in more detail.

[0092] 11 , a human detection device 100 according to a 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 determination unit 3 to be determined, and transmits the data to another device such as a display. The intrusion count suggestion data output unit 4 is physically provided as a computer common to the determination unit 3 described above.

[0093] For example, when the intrusion count suggestion data output unit 4 receives from the determination unit 3 an object detection position signal indicating the position where an object has intruded (here, any of sections I to VI), it acquires the time at which the signal was received, associates the section where the object has intruded with the corresponding reception time, and stores the association data in a predetermined area of ​​memory. Here, the reception history of the object detection position signal for each section is stored together as log data.

[0094] The intrusion count suggestion data output unit 4 references a predetermined 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 predetermined 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 grasped, and outputs this to a display.

[0095] 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.

[0096] [Fifth Embodiment] In the above-described embodiments, the determination unit determines that a person has entered the detection area and outputs a human detection signal when it identifies the detection position of an object within the detection area. In contrast, the determination unit according to the fifth embodiment determines that a person has entered the detection area and outputs a human detection signal when it identifies the detection position of an object and the detection position is set to an alert position.

[0097] For example, the determination unit refers to alert position data stored in advance in a predetermined area of ​​memory, and when 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, which is set for each of sections I to VI that divide the detection area. The alert position data stored in the predetermined area of ​​memory is held in a changeable state, and the determination unit is configured to change the alert position data automatically under predetermined conditions or when it receives a change command from outside.

[0098] With this configuration, the area of ​​the entire detection area where it is desired to detect a person entering the area can be designated as an alert position, and the other areas can be designated as non-alert positions, allowing the effective detection area to be set more flexibly.

[0099] 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 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 a section with a high number of object intrusions as a non-alert position through input from an input device configured to be able to communicate with the human detection device.

[0100] [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 on the base end side of the detection area X is set to pass above a predetermined height.

[0101] As a result, the overlapping area between the first projection area and the second projection area 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 it is desired to form a detection area at a position away from the human detection device 100.

[0102] [Other Embodiments] The determination by the determination unit of 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.

[0103] The detection signal used by the judgment unit to detect people and identify the object detection position may be an analog output signal indicating the amount of fluctuation in the incident infrared light detected by each infrared sensor, and regardless of the format of the detection signal, it is sufficient that the detection signal from both the first sensor unit and the second sensor unit is calculated to identify the object detection position.

[0104] For example, if the detection signal of a first sensor unit and the detection signal of a second sensor unit indicate values ​​above a predetermined threshold and the ratio of the values ​​indicated by these two detection signals is within a predetermined range, the judgment 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.

[0105] Furthermore, the determination unit may specify, based on the analog output signals of two or more first sensor units, an area where the first projection areas of the two or more first sensor units overlap with each other as the object detection position.

[0106] 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 area where the first projection area and the second projection area overlap based on a detection signal indicating the detection of an object from the first sensor unit and a detection signal indicating the detection of an object from 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 way, a human detection device using a pyroelectric PIR element can detect an object that has entered the first projection area and is moving straight toward the human detection device within the detection area when it enters the second projection area, thereby determining the approach of the object.

[0107] Although the number of first sensor units in each of the above embodiments is two or three, it may be four or more, as long as it is plural. 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 × 2" within the detection area.

[0108] A plurality of first sensor units and a single second sensor unit that forms a second projection area that overlaps with these first projection areas may be considered as one sensor unit group, and the human detection device may be equipped with multiple sensor unit groups.

[0109] The arrangement of the infrared sensors or optical members in each sensor unit is not limited to that described in the above embodiments, and the configurations of the infrared sensors and optical members may differ between the sensor units.

[0110] The infrared sensor may be a single type or a quad type, or may be another 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.

[0111] The unit zone does not have to be divided into a plurality of divided zones, in which case each optical element may be a single lens.

[0112] The optical member may be configured as a mirror, or may be configured as a combination of a lens and a mirror.

[0113] Although the human detection device in each of the above-described embodiments is configured with a sensor unit and a computer functioning as a determination unit, etc., provided in a common housing, the physical configuration of the human detection device according to the present invention is not limited to this. Furthermore, the physical locations of the components are not limited to the locations shown in each embodiment.

[0114] For example, the sensor unit may include an analog circuit including a comparator, an AD converter, and a digital electric circuit such as a computer or PLD, which may perform the function of the detection circuit, and this computer may be common to the determination unit. Furthermore, the sensor units do not have to be provided in the same housing, as long as they are arranged together to some extent.

[0115] Some or all of the functions of the determination unit or the intrusion count suggestion data output unit described above may be performed by an information processing device that is provided separately from the sensor unit and 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.

[0116] 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

1. A human detection device comprising a plurality of sensor units attached at a position higher than a reference surface, which form unit zones extending diagonally downward and which detect objects that have entered these unit zones; and a judgment unit that judges whether a human has entered a detection area formed by the unit zones of each sensor unit based on the detection signals from each of the sensor units, wherein the sensor units include a plurality of first sensor units and a single second sensor unit, wherein first projection areas, formed by projecting the unit zones of each of the first sensor units onto the reference surface as viewed from above, are set to be aligned in the left-right direction, and wherein second projection areas, formed by projecting the unit zones of the second sensor unit onto the reference surface as viewed from above, are set to overlap with each of the first projection areas, and wherein the leading edge of the first projection area is set to be located farther away than the leading edge of the second projection area, and wherein 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 to identify the object detection position in the detection area.

2. The human detection device of claim 1, wherein the judgment unit, when receiving a detection signal indicating that an object has been detected from both the first sensor unit and the second sensor unit, judges that an object has entered an area where the first projection area and the second projection area overlap, and when receiving a detection signal indicating that an object has been detected from only the first sensor unit, judges that an object has entered an area of ​​the first projection area that does not overlap with the second projection area.

3. A human detection device as described in claim 1, wherein the second projection area is set to have an outer area extending outward from the first projection area located at the left or right end of each of the first projection areas, and the judgment unit judges that an object has entered the outer area when it receives a detection signal indicating that an object has been detected from only the second sensor unit.

4. A human detection device as described in claim 1, wherein the first projection areas are arranged so as to partially overlap each other, and the judgment unit judges 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.

5. The sensor unit comprises a PIR element and an optical element that defines the unit zone, which is the range of infrared rays that are incident on the PIR element, and the optical element has a plurality of lenses lined up on the left and right, and the divided zones that are the infrared incident ranges defined by each lens are lined up on the left and right when viewed from above, and are configured to form the unit zone, and the number of lenses that define 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.

6. A human detection device as described in claim 1, further comprising 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.

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