JP2001229471A - Trespass detecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a trespass detecting device which can easily and securely detect a suspicious body from entering a warehouse, etc. SOLUTION: The device is equipped with ultrasonic-wave transmitter receivers 12 and 13 which send ultrasonic waves to a specific monitored area 4 and receive their reflected waves and a feature detecting function 21 which finds the reception timing of plural main reflected components of the ultrasonic waves as reflection characteristics of the ultrasonic waves in the monitored area according to the levels of the received ultrasonic waves and trespass deciding function 22. The function 22 stores the reflection characteristics of the ultrasonic waves found when the monitored area is in a stationary state as characteristic reference data in a memory 24 and compares reflection characteristics of ultrasonic waves found when the monitored area is monitored with the reference data to detect a foreign body entering the monitored area.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intrusion detection device capable of easily and reliably detecting intrusion of a suspicious object into a warehouse or the like.

[0002]

2. Related Background Art Recently, various security systems have attracted attention, and one of them is a device for monitoring entry of a suspicious object (suspicious person) into a specific monitoring target area.
Conventionally, this type of apparatus is configured to obtain an image of a monitoring target area exclusively using a TV camera and directly monitor the image. Recently, however, infrared light obtained from a light emitting diode is radiated into the monitoring area. Various attempts have been made to determine the intrusion of a suspicious object in the monitoring area from the change in the amount of reflected light.

[0003] In addition, using a laser beam to detect the intrusion of a suspicious object when its optical path is interrupted by a suspicious object, or detecting the intrusion of a suspicious object by using ultrasonic waves, particularly detecting a moving object. Attempted. By the way, moving object detection
Assuming that there is no moving object other than the suspicious person in the monitoring target area, attention is paid to the fact that the phase of the ultrasonic wave reflected by the suspicious person changes due to the Doppler effect accompanying the movement.

[0004]

However, when the image of the monitoring target area is manually monitored, a large labor cost is required. To detect the amount of reflected infrared light,
A high-sensitivity infrared detector is required, which inevitably increases equipment costs. Further, when using laser light, it is necessary to initialize the optical path of the laser light in advance according to the environment of the monitoring target area, and there is a problem that it is difficult to flexibly cope with various environments. Furthermore, when the ultrasonic wave is used as described above, there is a problem that it is difficult to detect the suspicious person, especially when the suspicious person moves slowly.

The present invention has been made in view of such circumstances, and has as its object to provide an intrusion detection device that can easily and reliably detect the intrusion of a suspicious object into a predetermined monitoring target area. Is to do.

[0006]

In order to achieve the above-mentioned object, an intrusion detection device according to the present invention comprises: an ultrasonic transmission means for transmitting ultrasonic waves to a predetermined monitoring target area such as a warehouse or a doorway of a building; Ultrasonic receiving means for receiving reflected waves of the ultrasonic waves from the monitoring target area, and receiving each of a plurality of main reflection components in the ultrasonic waves according to the level of the ultrasonic waves received by the ultrasonic receiving means; Characteristic detecting means for obtaining a wave timing as a reflection characteristic of the ultrasonic wave in the monitoring target area, and the reflection characteristic of the ultrasonic wave obtained by the characteristic detecting means when the monitoring target area is in a steady state. Is stored as reference data unique to the monitoring target area, and the reflection characteristics of the ultrasonic waves obtained by the feature detecting means at the time of monitoring the monitoring target area are stored in advance as described above. Wherein by comparing the reference data, and comprising the intruding object determination means for detecting a foreign material from entering the said monitoring target region that.

That is, according to the present invention, when an ultrasonic wave is transmitted to a predetermined monitoring target area and its reflected wave is received, when the monitoring target area is in a steady state, a plurality of main reflection components of the reflected wave are detected. It is noted that the wave reception timing is a unique timing that has passed through a propagation time according to the environment such as the arrangement of various articles in the monitoring target area. Accordingly, the reception timings of the plurality of main reflection components in a steady state (at the time of initial setting) are obtained and stored as reference data unique to the monitoring target area, and the reflection characteristics of the ultrasonic wave and the ultrasonic wave reflection characteristics similarly obtained during the monitoring are obtained. By comparing the reference data with the reference data, the presence of an intruder and the movement of the intruder can be reliably detected from the difference in the reception timing.

Preferably, the reception level of the ultrasonic wave received by the ultrasonic receiver is discriminated by a predetermined threshold, and a reflected wave having a level exceeding the predetermined threshold is detected. A plurality of timings are sequentially obtained as the reception timing of the main reflection component, and the reflection characteristic of the ultrasonic wave in the monitoring target area is obtained as a collection of these timing data.

Further, the intrusion detection device according to the present invention further comprises an infrared sensor for viewing the monitored area, wherein the temperature of the monitored area is detected by the infrared sensor. Is used as auxiliary means for judging the entry of foreign matter into the monitoring target area. That is, in addition to judging the intrusion of a foreign object based on the reflection characteristics of ultrasonic waves, a temperature change in the monitoring target area is detected using an infrared sensor, and whether the intruder is a small animal such as a rat is determined by the magnitude of the temperature change. This assists in determining the intrusion of a foreign substance into the monitoring target area, and accurately detects the intrusion of a suspicious person who should be monitored. In other words, it is characterized by preventing erroneous detection by small animals such as rats.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An intrusion detection device according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an example of a monitoring target area to be monitored for intrusion of a suspicious object, and schematically shows a state of a room 3 having a door 1 and a window 2. The area 4 to be monitored for the entry of a suspicious object into the room 3
It is set as a region near the door 1 and the window 2 from which the room 3 can enter and exit from the outside. In other words, the intrusion monitoring target area 4 is set so as to include an area that the intruder cannot avoid while entering the room 3.

In the intrusion detection device according to this embodiment, an ultrasonic sensor for transmitting ultrasonic waves and an ultrasonic sensor for receiving ultrasonic waves are used to transmit ultrasonic waves to the monitoring target area 4 and receive the reflected waves. A sensor unit 5 having an ultrasonic sensor is provided on a ceiling 6 of the room 3 as shown in FIG. 1, for example. Incidentally, each of the above-mentioned ultrasonic sensors transmits and receives ultrasonic waves having a conical directivity pattern forming a predetermined spread angle (for example, 50 ° to 100 °).

The sensor unit 5 is provided with such an ultrasonic sensor (element) exclusively for transmission and reception, respectively, and is configured by arranging these ultrasonic sensors side by side. However, one ultrasonic sensor may be time-divided via a selector or the like and used (switched) for transmission or reception. In addition, this sensor unit 5
The infrared sensor 13 for detecting the temperature of the intruder in the intrusion monitoring target area 4 as described later, for example,
Is incorporated.

The intrusion detection device provided with the sensor unit 5 as described above, for example, drives an ultrasonic sensor 11 for transmission as shown in FIG. Device 12, ultrasonic sensor 1 for reception
An ultrasonic receiver 14 that drives the 3 and receives the ultrasonic waves reflected by the monitoring target area 4 is provided. The intrusion detection device additionally includes an infrared temperature detector 16 that detects an infrared temperature in the monitoring target area 4 monitored by the infrared sensor 15.

Thus, the ultrasonic transmitter 12 is driven,
Further, the control unit 20 for inputting information on the reflected wave detected by the ultrasonic receiver 14 and further information on the infrared temperature detected by the infrared temperature detector 16 is constituted by, for example, a microprocessor. The control unit 20 basically determines the reflection characteristics of the ultrasonic wave in the monitoring target area 4 from the information of the reflected wave detected by the ultrasonic receiver 14, for example, the reception level of the reflected wave that changes with time. , A feature detecting function 21 for detecting the feature. Further, control unit 2
0 is an intrusion determination function 2 that detects the intrusion of a foreign object (suspicious person) into the monitoring target area 4 from the reflection characteristics of the ultrasonic wave detected using the feature detection function 21 as described above.
2 is provided. Also, the auxiliary determination function 23 provided in the control unit 20
Determines the temperature (calorific value) of, for example, a foreign substance (suspicious person) that has entered the monitoring target area 4 in accordance with the infrared temperature information detected by the infrared temperature detector 16. The invasion determination function 22 is assisted by determining whether the foreign object (suspicious person) is a small animal such as a mouse or a human having a large amount of heat according to the detected infrared temperature. And eliminates the invasion of small animals such as rats from the detection target, thereby enhancing the reliability of intrusion detection.

The memory 24 connected to the control unit 20
When the monitoring target area 4 is in a steady state, that is, when there is no intrusion of a suspicious object or the like, the reflection characteristics of the ultrasonic wave obtained by the feature
Is stored as reference data unique to the. When the intrusion determination function 22 detects intrusion of a foreign object, particularly a human (suspicious person), into the monitoring target area 4, the alarm generation unit 25 is driven by the intrusion determination function 22 to issue an alarm, It plays the role of notifying the monitoring center of intrusion detection information.

Here, a method of detecting the intrusion of a foreign substance into the monitoring target area 4 by using an ultrasonic wave will be described. The ultrasonic transmitter 12 is, for example, as shown in FIG. 11 is driven to transmit an ultrasonic wave to the monitoring target area 4 by panel transmission as shown in FIG. In the monitoring target area 4 receiving such an ultrasonic wave, for example, the floor or the wall surface in the room 3 and further reflected by furniture or equipment fixedly installed (arranged) in the room 3, and a part thereof is reflected. The light is propagated to the receiving ultrasonic sensor 13 described above. Therefore, the ultrasonic sensor 13 is an ultrasonic wave reflected at various parts of the monitoring target area 4 in accordance with the transmission of the ultrasonic wave from the ultrasonic sensor 11 described above, and exhibits a level change depending on the reflection conditions and the like. The obtained ultrasonic waves are received in time series after the respective propagation times as shown in FIG.

The temporal change pattern detected with the change in the level of the received ultrasonic wave (reflected wave) is constant as long as the monitoring target area 4 does not change.
Therefore, in the feature detection function 21 described above, the level of the received ultrasonic wave is discriminated by the predetermined threshold value TH as described above, and the reception timing at which the reflected wave having the reception level exceeding the threshold value TH is detected is shown in FIG. As shown in FIG. 3D, the transmission timing to of the ultrasonic wave is used as a reference, and the reference timing to is used.
Are detected as elapsed times t1, t2, t3, t4,... The reception timings t1, t2, t3, t4,... At which these major reflected waves are obtained are regarded as reflection characteristics indicating the monitoring state of the monitoring target area 4.

In particular, in the control unit 20, when the monitoring target area 4 is in a normal state, the reception timings t1, t2,
The reflection characteristics consisting of t3, t4,... are obtained as reference data unique to the monitoring target area 4, and this reference data is stored in the memory 24.
Is stored in And in the intrusion determination function 22,
By using the reference data stored in the memory 24 and comparing with the characteristics of the reflected waves (wave reception timings ts1, ts2, ts3, ts4,...) Obtained when monitoring the monitoring target area 4, the reflection characteristics can be obtained. It is determined whether or not a change has occurred, and the intrusion of a foreign object (suspicious person) into the monitoring target area 4 is detected.

The reception timings t1, t2, t3, t4,
Are 8-bit digital data with a distance resolution of 20 mm in the monitoring target area 4 to be detected using ultrasonic waves, for example, a maximum of 256
It is expressed as a detection distance of a reflected wave from the main reflector in a range up to 0 mm. With respect to the reception timings t1, t2, t3, t4,... Of the main reflected waves obtained in this manner, if about five points are extracted in ascending order of reception timing, sufficient characteristics unique to the monitoring target area 4 can be obtained. It is possible to catch it.

Thus, the reference data (wave reception timings t1, t2, t3, t4,...) Thus stored in the memory 24.
And the characteristics of the reflected waves (wave reception timings ts1, ts2, ts3, ts4,...) Determined at the time of monitoring the monitoring target area 4 are compared and collated by the intrusion determination function 22, and a foreign substance (suspicious According to the present apparatus for detecting the intrusion of a person, the reception timings ts1 and ts indicating the reflection characteristics as shown in FIGS.
Since 2, 2, ts3, ts4,... Change, it is possible to easily detect the intrusion of foreign matter and to reliably detect the foreign matter.

More specifically, a new main reflection component having a high reception level is detected due to the invasion of a foreign matter, and for example, a new main reflection component is detected as shown in FIG.
As shown in the figure, the reception timings ts1, ts2, ts3, ts4,
Are found, there is almost no deviation from the reference data timing t1 at the first reception timing ts1, but there is a large time difference between the second reception timing ts2 and the reference data timing t2. Slippage occurs. Then, the third reception timing ts3 is collated with the timing t3 although it originally corresponds to the timing t2 of the reference data, so that a large time lag also occurs here. . As a result, a mismatch with the reference data is detected, and the intrusion of a foreign substance (suspicious person) into the monitoring target area 4 is detected.

Also, a newly reflected wave generated by the invasion of a foreign substance enters the main reflection component of the monitoring target area 4 and, for example, only the third reception timing ts3 changes as shown in FIG. 3 (f). Even in such a case, the time lag can be detected by comparing the reference data with the timing t3, so that the intrusion of a foreign substance (suspicious person) into the monitoring target area 4 is detected. .

In this manner, the reception timing ts1,
When comparing and collating the reflection characteristics indicated by ts2, ts3, ts4,.
In order to exclude the movement of an object having a diameter of less than mm from the detection target, it is sufficient to disregard a case where the difference between the reception timings obtained by the comparison and matching is within a predetermined time difference. If such measures are taken, the ultrasonic sensors 11, 13
Thus, the effect of fluctuations (error factors) of the detection characteristics such as the above can be removed, thereby enabling stable intrusion detection.

Further, when detecting the intrusion into the monitoring target area 4 as described above, if the type of the intruder is determined from the infrared temperature detected by the infrared sensor 15, it may be caused by a factor other than a human who intrudes maliciously. It is possible to effectively prevent erroneous intrusion detection, it is possible to prevent the occurrence of alarms due to erroneous detection and unnecessary dispatch of guards, etc.
It is possible to effectively assist the above-described intrusion detection using ultrasonic waves.

When the above-described intrusion detection processing is executed by the control unit 20 including a microprocessor, the processing may be performed according to, for example, a processing procedure shown in FIG. That is, the sensor unit 5 is installed so as to view the predetermined monitoring target area 4 and its initial setting is performed [Step S1], and the ultrasonic transmitter 12 is driven to transmit ultrasonic waves [Step S2]. Then, a reflected wave of the ultrasonic wave by the monitoring target area 4 is received [Step S].
3], the received data is discriminated at a predetermined level, and the reception data is encoded by obtaining the reception timing or the like [Step S]
4].

Thereafter, it is determined whether or not it is possible to detect the intrusion of a foreign object into the monitoring target area 4 at this time [Step S5]. If there is no comparison reference data,
The encoded data is stored in the memory (register) 24 as reference data (initial data) indicating the reflection characteristics of the ultrasonic wave unique to the monitoring target area 4 [Step S6]. By storing the reference data in the memory 24, the preparation for detecting the intrusion of a foreign substance into the monitoring target area 4 is prepared.

Thereafter, the ultrasonic waves are periodically transmitted again to the monitoring target area 4 [Step S2], and the reflected waves are received and the received data is encoded [Steps S3 and S].
4]. At this point, since the reference data of the monitoring target area 4 has already been obtained in the memory 24, the received data is compared with the reference data stored in the external memory 24 (step S7). At this time, when the infrared sensor 15 is provided, the determination of the foreign matter based on the infrared temperature is also performed [Step S8]. Then, according to these comparison and collation results, it is determined whether or not a foreign object has entered the monitoring target area 4 [Step S9]. If the foreign object has been detected, a detection signal is generated and an alarm is issued. Execute [Step S10].

However, when no intrusion of foreign matter into the monitoring target area 4 is detected, or when the invading object is a small animal such as a mouse,
If this can be ignored, the above-described processing procedure from step S2 is repeatedly executed without issuing the above-described detection signal. Such a monitoring process may be performed only in a non-working time zone at night, for example, in an office building or the like, and may be constantly operated in a warehouse or the like, and only when a predetermined worker breaks down. The monitoring may be interrupted.

The present invention is not limited to the above embodiment. Here, the monitoring of one monitoring target area 4 has been described as an example, but when a plurality of monitoring target areas exist, the sensor unit 5 may be provided for each monitoring target area. It is also useful to embed the sensor unit 5 on the floor or wall. Also, by sequentially learning the characteristic data of the reflected wave registered as the reference data, standard reference data absorbing the fluctuation of the reception timings t1, t2, t3, t4,. May be.

Further, as an application example of the present invention, a sensor unit 5 is provided in, for example, a toilet or a bathroom, and characteristic data of a steady reflected wave in a state where no person is present in the monitoring target area is obtained as reference data. deep. In the use of toilets and bathrooms, the use of the fact that the characteristics of the reflected wave changes at a certain time due to the movement of a person. Conversely, when the change in the characteristics of the reflected wave is no longer recognized, the reflection characteristics are used. By comparing with the reference data, an abnormality in the monitoring target area, for example, a state in which a person is falling down may be detected. By employing such a detection algorithm, it is possible to obtain an effect such that an unexpected accident caused by sudden illness due to a seizure in a toilet or a bathroom can be detected early. In addition, the present invention can be variously modified and implemented without departing from the gist thereof.

[0031]

As described above, according to the present invention, a reflected ultrasonic wave transmitted to a predetermined monitoring target area is received,
Since the reception timing of each of the plurality of main reflection components in the reflected wave is determined as the reflection characteristic of the ultrasonic wave in the monitoring target area, the reflection characteristic of the ultrasonic wave required when the monitoring target area is in a steady state is monitored. As the reference data unique to the target area, it is possible to reliably detect the intrusion of a foreign substance into the monitored area from the reflection characteristics of the ultrasonic wave obtained at the time of monitoring. Moreover, the intrusion of a foreign substance into a predetermined monitoring target area can be detected simply and reliably by effectively utilizing a simple sensing means called an ultrasonic wave and without using a complicated detection method such as a Doppler effect. Thus, a great effect in practical use, such as being able to be achieved, can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a monitoring target area monitored using an intrusion detection device according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a main part of an intrusion detection device according to an embodiment of the present invention.

FIG. 3 is a timing chart for explaining the operation of intrusion detection using ultrasonic waves by the intrusion detection device according to one embodiment of the present invention.

FIG. 4 is a diagram showing an example of a processing procedure in a control unit for realizing intrusion detection using ultrasonic waves according to the present invention.

[Explanation of symbols]

 4 Intrusion monitoring target area 5 Sensor unit 11 Ultrasonic sensor for transmission 12 Ultrasonic transmitter 13 Ultrasonic sensor for reception 14 Ultrasonic receiver 15 Infrared sensor 16 Infrared temperature detector 20 Control unit (microprocessor) 21 Feature detection Function 22 Intrusion determination function 23 Auxiliary determination function 24 Memory 25 Alarm generator

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5C084 AA02 AA07 AA14 BB05 BB24 CC17 DD03 DD41 EE01 GG07 GG09 GG39 GG43 GG52 GG54 GG57 GG65

Claims (3)

[Claims] 1. An ultrasonic transmitting means for transmitting an ultrasonic wave to a predetermined monitoring target area; an ultrasonic receiving means for receiving a reflected wave of the ultrasonic wave from the monitoring target area; A characteristic detecting unit that obtains each reception timing of a plurality of main reflection components in the received ultrasonic wave as a reflection characteristic of the ultrasonic wave in the monitoring target region; and the characteristic detecting unit when the monitoring target region is in a steady state. Means for storing the reflection characteristics of the ultrasonic waves determined in the as the reference data unique to the monitoring target area, and the reflection characteristics of the ultrasonic waves determined by the characteristic detecting means when monitoring the monitoring target area, An intrusion detection device comprising: intrusion determination means for detecting intrusion of a foreign object into the monitoring target area by comparing with reference data stored in advance. 2. The reflection characteristic of the ultrasonic wave discriminates a reception level of an ultrasonic wave received by the ultrasonic receiver with a predetermined threshold, and a reflected wave having a level exceeding the predetermined threshold is detected. 2. The intrusion detection apparatus according to claim 1, wherein a plurality of timings are sequentially obtained as reception timings of the main reflection component, and the timings are obtained as a set of these timing data. 3. The intrusion detection device according to claim 1, further comprising an infrared sensor for viewing the monitoring target area,
An intrusion detection device characterized in that information on the temperature of the monitored area detected by the infrared sensor is used as auxiliary means for determining the intrusion of a foreign substance into the monitored area.