JP5151687B2 - Human body detection device and human body detection system using the same - Google Patents

Description

  The present invention relates to a human body detection apparatus, and more particularly to a human body detection apparatus suitable for use in an apparatus having a mechanism for detecting a human body by a pyroelectric infrared sensor.

  In recent years, the use of infrared sensors for the purpose of equipment control and security such as air conditioning and lighting is increasing. Infrared sensors are broadly divided into thermal types and quantum types. Among the thermal types, pyroelectric types are particularly popular because of their low cost.

  This pyroelectric infrared sensor is a sensor that detects a thermal object based on the amount of change in infrared rays in the detection region. Therefore, even when the purpose is to detect a human body, there is a high possibility of erroneous detection if there is a thermal variation around the detection region. Especially outdoors, it is susceptible to thermal disturbances such as sunlight and wind. Moreover, the detection area | region of an infrared sensor may be obstruct | occluded when a plant shakes with a wind, and small animals, such as a dog and an insect, may obstruct | occlude a detection area | region. Therefore, reducing the false detection rate is a problem when providing a human body detection device using a pyroelectric infrared sensor.

  In the pyroelectric infrared sensor according to the prior art, a plurality of pyroelectric elements are arranged to give different polarities to each other, and the detection range of the pyroelectric element is projected by an optical lens, so that the detectable range and distance are configured. There is something. In this conventional pyroelectric infrared sensor, when there is a thermal fluctuation that covers the entire detection range, the output voltage of the pyroelectric element cancels out depending on the polarity of each element, so that it is not detected as a result. ing.

  As a patent document for reducing false detection using an infrared sensor, Patent Document 1 can automatically change and set a preset pulse count time and pulse count number according to the infrared output output by the infrared detection device. Thus, a method for reducing erroneous detection due to the influence of wind and sunlight is disclosed. Patent Document 2 discloses an apparatus that prevents erroneous detection by using an infrared sensor and an ultrasonic sensor in combination.

JP-A-8-179050 JP 2005-214946 A

  In each of the above-mentioned patent documents, a special mechanism is added to a detection device using an infrared sensor to prevent erroneous detection.

  However, especially when used outdoors where it is difficult to assume the movement of the human body, the human body detection device accurately detects the human body even in an environment where there is a thermal disturbance, and is an inexpensive device equipped with means having a wide detection area as much as possible. is necessary.

  The present invention has been made to solve the above-described problems, and its purpose is to prevent erroneous detection due to thermal effects from sunlight, wind, plant fluctuations, and small animals even when used outdoors. An object of the present invention is to provide a human body detection device that is inexpensive and easy to handle.

  In order to achieve the above object, in the human body detection device of the present invention, using a plurality of pyroelectric infrared sensors with different sizes of detection areas, the infrared sensor selection condition among the plurality of pyroelectric infrared sensors, In accordance with the environmental conditions at that time, an optimum pyroelectric infrared sensor that is less affected by thermal disturbance is selected. In addition, the number of times the selected pyroelectric infrared sensor is detected within a certain period of time is determined based on the human body detection condition to determine whether it is a thermal disturbance or a human body.

  According to the present invention, there is provided an inexpensive and easy-to-handle human body detection device that does not make a false detection due to thermal effects caused by sunlight or wind, fluctuations in plants, or small animals even when used outdoors. Can do.

  Embodiments according to the present invention will be described below with reference to FIGS.

Embodiment 1
First, the configuration of the human body detection device according to the first embodiment of the present invention will be described.
FIG. 1 is a configuration diagram of the human body detection device according to the first embodiment of the present invention.

  As shown in FIG. 1, the human body detection device 0 according to the present embodiment includes a pyroelectric infrared sensor 1, a measurement unit 3, a control unit 4, a communication unit 5, a power supply unit 6, a clock 7, a storage unit 8, and the sun. The optical sensor 9 is used.

  The pyroelectric infrared sensor 1 is a sensor that receives infrared rays generated by an object, converts the infrared rays into heat, and converts the heat into electric charges by the pyroelectric effect of the element. The pyroelectric infrared sensor 1 is composed of a plurality of pyroelectric elements having positive and negative polarities. Depending on the number of pyroelectric elements, for example, there are those called dual type and quad type. Further, it may be configured by using four or more pyroelectric elements.

  In the pyroelectric infrared sensor 1, a Fresnel lens 2 is attached to the light receiving portion of the pyroelectric infrared sensor 1, and the detection area of the pyroelectric infrared sensor 1 is projected in a plurality of directions, and the detection distance and the detection range. That is, the detection area as a sensor is determined. Thus, the detection area of the sensor can be easily determined by the number of pyroelectric elements of the pyroelectric infrared sensor and the shape of the Fresnel lens. Examples of detection area types include those capable of detecting fine movements of several tens of centimeters, spot types having a detection angle of 20 degrees or less, and detection distances of several tens of meters. The detection area p has a positive polarity, and the detection area m has a negative polarity.

  The measurement unit 3 is a part that measures conditions related to the external environment, and is, for example, a sunlight sensor or a temperature sensor.

  The control unit 4 is a processor that receives signals from the respective units, performs calculations related to operation conditions, and gives instructions to the respective units. A particularly important process of the control unit 4 is to receive a signal as an output from the pyroelectric infrared sensor 1 and determine whether to detect a human body.

  The communication unit 5 is a part that controls an interface for connecting to a network. The communication unit 5 includes, for example, a wireless communication device or a serial communication device compliant with the IEEE 802.15.4 standard. The human body detection device 0 can take in necessary information through a network connected by the communication unit 5 and output a human body detection result via the network. The information output from the communication unit 6 to the network is transmitted to, for example, a wireless repeater or an alarm device, and can be used for security or device control.

  The storage unit 8 is a nonvolatile or volatile semiconductor memory, and stores a program for executing the control unit 4, data on various operating conditions, and temporary data. Examples of data relating to various operating conditions include an infrared sensor selection condition, a human body detection condition, and a false detection determination condition for the pyroelectric infrared sensor 1. Data related to various operating conditions may be received by the communication unit, or may be input and set to each human body detection device 0.

  The clock 7 generates a periodic signal for synchronization when each part of the human body detection device 0 operates. Usually, an oscillation circuit using a crystal resonator is used.

  The power source 6 is a part that supplies power to each part of the human body detection device 0. A circuit for converting household AC power into DC power may be used, or a battery may be used.

Next, switching of the pyroelectric infrared sensor will be described with reference to FIGS.
FIG. 2 is a diagram for explaining how the pyroelectric infrared sensor is switched.
FIG. 3 is a diagram illustrating the detection area of each sensor.

  In the present embodiment, a case where the human body detection device 0 has two pyroelectric infrared sensors 1a and 1b will be described as an example. In FIG. 2, each part of the human body detection device 0 is shown only as necessary for explanation, and the others are omitted.

  The control unit 5 has a function of selecting and switching between the pyroelectric infrared sensor 1a and the pyroelectric infrared sensor 1b according to the environmental conditions around the human body detection device 0.

  FIG. 1A shows a state where the pyroelectric infrared sensor 1a is selected, and FIG. 1B shows that the pyroelectric infrared sensor 1b is selected. State.

  Here, the pyroelectric infrared sensor 1a has a detection region pa having a positive polarity and a detection region ma having a negative polarity. The pyroelectric infrared sensor 1b has a detection region pb having a positive polarity and a detection region mb having a negative polarity.

  The pyroelectric infrared sensor 1a is as shown in FIG. 3A when viewed from the front of the sensor, and the pyroelectric infrared sensor 1b is a pyroelectric type as shown in FIG. 3B. The infrared sensor 1a is wider than the pyroelectric infrared sensor 1b. The detection areas of the pyroelectric infrared sensor 1a and the pyroelectric infrared sensor 1b are formed by Fresnel lenses 3a and 3b provided in the light receiving unit, respectively.

  Next, the operation of the human body detection device 0 according to the first embodiment of the present invention will be described using FIG.

  FIG. 4 is a flowchart showing the operation of the human body detection device 0.

  First, the infrared sensor selection condition and the human body detection condition are received from the outside by the communication unit 6 and recorded in the recording unit 8 via the control unit 5 (S1).

  Next, the control unit 5 selects either the pyroelectric infrared sensor 1a or the infrared sensor 1b based on the infrared sensor selection condition recorded in the recording unit 8 (S2).

  The purpose of selecting either the pyroelectric infrared sensor 1 or the pyroelectric infrared sensor 7 is to select a sensor with a different detection range, and when there is a large influence of thermal disturbance, the pyroelectric type with a narrow detection range. The basic policy of selection is to select an infrared sensor. For example, when an alley is monitored using the human body detection device of the present embodiment in the outdoors where sunlight is inserted and plants such as trees are present, in the daytime, the background becomes the ground and shadow due to the influence of sunlight. The temperature difference between the parts increases. At this time, if plants such as trees fluctuate by the wind and block the detection area of the pyroelectric infrared sensor 1, the pyroelectric infrared sensor 1 will detect. Therefore, in such a case, the control unit 5 selects the pyroelectric infrared sensor 1b having the narrower detection area. The pyroelectric infrared sensor 1b has a narrow detection area, and therefore does not block the detection area even if trees are fluctuated by the wind. At least the detection area of the pyroelectric infrared sensor 1b is not affected by trees.

  In this embodiment, two types of detection area sensors are selected, but two or more types may be selected, and a pyroelectric infrared sensor or a Fresnel lens may be selected in accordance with the installation location of the human body detection device. Is possible.

  In accordance with the above basic policy, in the present embodiment, the pyroelectric infrared sensor 1a having a narrow detection area is selected during the daytime, and the pyroelectric infrared sensor 1a having a wide detection area is selected other than during the daytime. This is because, at night when there is no influence of sunlight, even if the detection area of the sensor is wide and there are only a few trees, it is unlikely that erroneous detection will occur due to thermal disturbance. In this selection, a daytime time zone may be determined and a pyroelectric infrared sensor may be selected, or sunlight or air temperature is detected by the measurement unit 3 shown in FIG. The pyroelectric infrared sensor may be selected by telling it.

  Further, in the case of thermal disturbance, wind, etc., a pattern in the case where the human body detection device 0 reacts is provided as an erroneous detection determination condition, and when this erroneous detection determination condition is repeated for a certain period of time, A narrow pyroelectric infrared sensor may be selected.

  Then, the number of detections within a predetermined time is counted by the control unit 5 (S3). In step S2, an appropriate pyroelectric infrared sensor that takes thermal disturbance into consideration is selected by selecting one of the sensors with different detection ranges. In step S3, is the thermal disturbance detected? In order to determine whether or not it is a human body, the number of detections of the pyroelectric infrared sensor within a certain time is counted, and the count number is used. For example, when the human body passes through the detection area of the sensor, it is counted twice in a certain second. In this way, when the count is counted, the condition that the human body is detected may be notified from the external network as the human body detection condition, or is set in the human body detection device 0 in advance. You may do it.

  Moreover, since a suspicious person wanders near the target object, a difference occurs in the number of counts between a mere passing person and a suspicious person. Therefore, if the human body detection device 0 is used for the purpose of monitoring the vicinity of a door or a stolen object and wants to determine a suspicious person, the suspicious person detection is detected as a variation of the human body detection condition, such as counting five times in a certain second. Conditions may be provided, stored in the storage unit 8, and used for suspicious person detection.

  Next, the control part 5 determines whether it is a human body from the frequency | count of detection within the fixed time obtained by the step of S3 (S4). Further, as the contents of the human body detection condition, when a human body is detected, it is determined whether or not the person is a suspicious person.

  And the determination result of a human body detection is notified outside by the communication part 6 (S5).

  In addition to the above, it is also possible to determine the thermal disturbance and the human body by combining the sensor selection condition and the human body determination condition. For example, an infrared sensor selection condition is provided as a condition for the number of detections smaller than the human body determination condition, and the number of detections for a certain period of time is less than the number of times determined as a human body in the human body determination condition. If there are more, a sensor with a narrow detection range is selected. As a result, if there is no detection by the sensor, it is determined that there is a thermal disturbance.

[Embodiment 2]
Hereinafter, a second embodiment according to the present invention will be described with reference to FIG.
In the present embodiment, a human body detection system using the human body detection device according to the first embodiment will be described.
FIG. 5 is a configuration diagram of a human body detection system using the human body detection device.

  The human body detection system using the human body detection device according to the present embodiment has a configuration in which one parent device 100 and a plurality of human body detection device nodes 110 are connected by a mesh-type wireless network.

  In this wireless network, for example, ZigBee (ZigBee is a registered trademark) using the IEEE 802.15.4 standard for the physical layer and the MAC layer can be used.

  One parent device 100 exists in the system, and is a personal computer having a ZigBee communication interface, for example, which holds system setting conditions and distributes them to each node, and each human body detection device node 110 It is a device that receives and displays the detection result, and is a device that corresponds to ZC (ZigBee Coordinator) in the ZigBee standard.

  The parent device 100 includes a CPU 101, a storage unit 102, a communication unit 103, a storage device interface 104, and a display device interface 105.

  The CPU 101 is a processor that controls each unit, and executes necessary programs.

  The storage unit 102 holds programs executed by the CPU 101 and temporary data.

  The storage device interface 104 is an interface for connecting the external storage device 200.

  The display device interface 105 is an interface for connecting the display device 300.

  The external storage device 200 is a device having a large storage capacity, for example, an HDD (Hard Disk Drive). The external storage device 200 may be configured with a semiconductor memory such as a nonvolatile memory.

  The display device 300 is a device that displays information, and is, for example, an LCD (liquid Crystal Display).

  The communication unit 103 is an interface for performing wireless communication with the human body detection device node 110 via the antenna 106.

  The external storage device 200 holds an infrared sensor selection condition 20, a human body detection condition 21, and an erroneous detection determination condition 22. This may be common to each node, or a different value may be used for each node.

  In addition, the external storage device 200 holds a movement path determination program 30. The movement path analysis program 30 is a program for analyzing the movement path of a person whose human body is detected based on information from each human body detection device node 110.

  The human body detection device node 110 is a network node configured by the human body detection device 0 described in the first embodiment, and is a device corresponding to ZR (ZigBee Router) in the ZigBee standard.

  Although omitted in FIG. 5, the human body detection device node 110 has the same components as the human body detection device 0 of the first embodiment, and includes a pyroelectric infrared sensor 111a having a wide detection area, and detection. It has a function of switching the pyroelectric infrared sensor 111b having a narrow area.

  In addition, the communication unit 113 can wirelessly communicate with the parent device 100 and other human body detection device nodes 110 via the antenna 114.

  In the present embodiment, each human body detecting device node 110 transmits information on detecting a human body to the parent device 100 using the data relay function of the mesh network with a data structure of (node number, time when human body is detected). . When receiving this, base unit 100 stores it in storage unit 102 or storage device 200.

  Based on the stored information of each human body detection device node 110, the base unit 100 is detected by collecting and analyzing these human body detection device nodes 110 by executing the movement path analysis program 30. Specify the movement path of the human body. At this time, the route may be displayed by a solid line or a dotted line on the map displayed on the display device 300.

  As described above, when a plurality of human body detection devices are arranged on a site, the route through which the human body passes can be identified from the human body determination information of each human body detection device. This is suitable, for example, for security management of orchards and facilities.

  Furthermore, when information determined to be human body detection is communicated from a plurality of human body detection devices that cannot normally occur at the moving speed of the human body, a plurality of human body detection device nodes 110 communicate this with the influence of wind or large scale. It can be determined that a thermal disturbance has occurred.

It is a block diagram of the human body detection apparatus of 1st embodiment which concerns on this invention. It is a figure explaining a mode that the pyroelectric infrared sensor is switched. It is a figure explaining the detection area | region of each sensor. 5 is a flowchart showing the operation of the human body detection device 0. It is a block diagram of the human body detection system using a human body detection apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 0 ... Human body detection apparatus 1 ... Pyroelectric infrared sensor 2 ... Fresnel lens 3 ... Measurement part 4 ... Control part 5 ... Communication part 6 ... Power supply part 7 ... Clock 8 ... Memory | storage part pa ... The polarity of the pyroelectric infrared sensor 1a Positive detection area ma... Detection area pb with negative polarity of pyroelectric infrared sensor 1a. Detection area mb with positive polarity of pyroelectric infrared sensor 1b... Detection area with negative polarity of pyroelectric infrared sensor 1b.

Claims (7)

A pyroelectric infrared sensor having a plurality of detection areas of different sizes;
A storage unit for holding an infrared sensor selection condition for selecting the pyroelectric infrared sensor and a human body detection condition for determining that a human body is detected from an output from the pyroelectric infrared sensor;
Based on the infrared sensor selection condition, select the plurality of pyroelectric infrared sensors, receive an output from the selected pyroelectric infrared sensor, from the output of the pyroelectric infrared sensor, based on the human body detection condition, A controller that outputs information on the result of human detection;
A human body detection apparatus comprising: a communication unit that communicates information on a result of the human body detection to the outside. Furthermore, it has a measuring part,
The measurement unit is a solar sensor,
When there is a lot of sunlight measured by the measurement unit, the control unit selects a pyroelectric infrared sensor with a small detection area,
The human body detection device according to claim 1, wherein when the sunlight measured by the measurement unit is low, the control unit selects a pyroelectric infrared sensor having a large detection area. The storage unit has false detection determination conditions,
The output of the pyroelectric infrared sensor, if it meets a certain time to the false positive determination condition, the control unit, according to claim 1, characterized in that selecting a test knowledge area is smaller pyroelectric infrared sensor The human body detection device described.   The human body detection device according to claim 1, wherein the human body detection condition is a number of detections of the pyroelectric infrared sensor output from the pyroelectric infrared sensor for a predetermined time. Wherein a detection frequency of a certain time of the pyroelectric infrared sensor, a different detection frequency is determined suspicious person detection condition, according to claim 4, wherein the holding in the storage unit of the human body detection condition stipulated Human body detection device.   The human body detection device according to claim 1, wherein the communication unit operates in conformity with the IEEE 802.15.4 standard. With one base unit,
It consists of multiple human body detection device nodes,
The base unit, the human body detection device node, and the plurality of human body detection device nodes communicate with each other according to the IEEE 802.15.4 standard.
The human body detection device node is:
A pyroelectric infrared sensor having a plurality of detection areas of different sizes;
A storage unit for holding an infrared sensor selection condition for selecting the pyroelectric infrared sensor and a human body detection condition for determining that a human body is detected from an output from the pyroelectric infrared sensor;
Based on the infrared sensor selection condition, select the plurality of pyroelectric infrared sensors, receive an output from the selected pyroelectric infrared sensor, from the output of the pyroelectric infrared sensor, based on the human body detection condition, A controller that outputs information on the result of human detection;
A human body detecting device that communicates with the parent device or the other human body detecting device node and includes a communication unit that communicates information on a result of the human body detection to the outside,
The base unit is
CPU that executes processing and controls each unit;
A storage unit for storing programs and data;
A display interface for connecting a display device;
A storage device interface for connecting an external storage device;
A communication unit that communicates with the human body detection device node;
The external storage device is
Infrared sensor selection conditions,
Human body detection conditions,
A travel path analysis program,
The base unit transmits the infrared sensor selection condition and the human body detection condition to each human body detection device node, and each received human body detection device node transmits the received human body detection condition to each human body detection device node. In the storage section of
The human body detection device node transmits information of the human body detection result as a pair of information for identifying the node and a time when the human body is detected, via another human body detection device node or directly to the parent device. And
The master unit receives information on the result of the human body detection from the human body detection device node, and holds the information in the storage unit.
The control unit executes the movement path analysis program and calculates a movement path of the detected human body from information on the human body detection results of the plurality of human body detection device nodes held in the storage unit. And displaying on the display device.

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