JP2011215775A - Object detection sensor and security system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an object detection sensor for allowing prevention of misdetection caused by a change of a monitoring region and detection of a change that affects the monitoring performance, even in a sequentially changing environment, including the outdoors.SOLUTION: This object detection sensor monitoring the inside of a caution region to detect an object inside the caution region includes: a storage part previously storing the caution region; a detection part periodically scanning the inside of the caution region to generate ranging data, indicating the distance to the measured object in each direction in the caution region; a disturbance deciding portion for comparing the present ranging data and the caution region for deciding the presence or the absence of occurrence of visual field disturbance; a reference data generating section for generating reference data of each direction inside the caution region, based on the ranging data at a prescribed time point after a periodic scanning start; and an intrusion deciding portion for comparing the present ranging data and the reference data for deciding the presence or the absence of an intruding object.

Description

  The present invention relates to an object detection sensor that detects a distance to an object to be detected in a monitoring area by projecting and receiving light, and more particularly to an object detection sensor that detects a change that affects monitoring performance.

  Conventionally, in order to monitor a wide monitoring range, such as outdoors, a variety of survey signals such as laser light, visible light, ultrasonic waves, infrared rays, etc. are irradiated within the monitoring range and a reflected regression signal from the object is received. An object detection sensor for detecting an object in a monitoring range is known.

  For example, Patent Document 1 discloses a security system using a laser sensor that projects laser light while rotating and scanning a predetermined angle range and determines the presence of an intruder based on a distance value calculated when receiving reflected light. Has been.

Japanese Patent Laid-Open No. 10-244102

  The laser sensor disclosed in Patent Document 1 scans a monitoring area with laser light, and detects an intruder on the condition that data in the same region calculated from distance data and angle data continuously changes a plurality of times. .

However, since the outdoor environment can change sequentially, as described in Patent Document 1, simply assuming that the distance data continuously changes a plurality of times, it is possible to plant from among the changes that frequently occur in the outdoor environment. It is difficult to detect suspicious individuals by eliminating false detection factors such as plant growth and buds, and the appearance of new installations.
For this reason, there is a possibility that the laser sensor disclosed in Patent Document 1 is likely to be erroneously detected with respect to those that are unlikely to be suspicious persons, and thus it is difficult to determine a suspicious person that should be truly detected. is there.

  On the other hand, even if the change is not likely to be a suspicious person, such as the growth or bud of planting that appears as a false detection factor, or the appearance of a new installation, it is detected if this has a significant impact on monitoring performance. There is a need to alarm.

  Accordingly, an object of the present invention is to propose an object detection sensor that can prevent erroneous detection due to a change in a monitoring area even in an environment that changes sequentially, such as outdoors, and can detect a change that affects monitoring performance.

  In order to achieve the above object, an object detection sensor according to the present invention is an object detection sensor that monitors an inside of a warning area and detects an object in the warning area, and a storage unit that stores the warning area in advance, A detection unit that periodically scans the inside of the alert area and generates distance measurement data indicating the distance to the object to be measured in each direction in the alert area, and compares the current distance measurement data with the alert area A disturbance determination unit that determines whether or not visual field disturbance has occurred, a reference data generation unit that generates reference data for each direction in the alert area based on distance measurement data at a predetermined time after the start of periodic scanning, An intrusion determining unit that compares the distance measurement data and the reference data to determine the presence / absence of an intruding object.

  In such a configuration, the object detection sensor compares the current distance measurement data obtained by scanning the alarm area with the alarm area stored in advance to determine visual field disturbance, and the current distance measurement data is determined at a predetermined time point. Compared with reference data generated from distance measurement data, the presence of an intruding object is determined, and different comparison information is used depending on the abnormality of the detection target.

  According to such a configuration, even in an outdoor environment where the position and movement of an object can change day by day, the current warning area and the current range are set as warning ranges for security planning from the sensor characteristics and detection range. By detecting the relative deviation from the measurement results, it is possible to maintain security, and by comparing the reference data generated from the distance measurement data at a given point in time with the current measurement results. It is possible to detect an intruding object that enters a reference data dynamically corresponding to an environment that can be changed daily.

  The object detection sensor of the present invention further includes a communication unit connected to a security device that monitors a monitoring area including the security area, and the detection unit receives an input of a security start signal from the security device. The scanning is started and the scanning is terminated when receiving a security release signal from the security device, and the reference data generation unit is based on distance measurement data when the security start signal is received from the security device. Reference data for each direction in the alert area may be generated.

  As a result, it is possible to prevent damage to the drive parts due to continuous operation by driving the scanning unit while guarding the guard device. It is possible to detect an object that has entered the space.

  Moreover, the object detection sensor of this invention WHEREIN: The said memory | storage part may memorize | store the said alert area as two-dimensional information which consists of the distance and direction from the said detection part.

  Thereby, the comparison with the distance measurement data acquired by scanning by the detection unit is facilitated, and the processing speed can be increased.

  In the object detection sensor of the present invention, the interference determination unit may calculate a distance difference between the distance stored as the alert area for each direction and the distance to the measured object obtained from the current distance measurement data. Finding the obstruction area that is obstructed by the object to be measured in the alert area from the distance difference for each direction, and if the obstruction area is a predetermined ratio or more with respect to the area of the alert area, visual disturbance occurs. You may judge.

  As a result, it is possible to determine the occurrence of obstructive action on the object detection sensor based on the range that cannot be measured with the current measurement results for the warning area that is set in advance as the range to be guarded for security planning, and monitor the effectiveness of the monitoring field of view. Thus, it is possible to maintain and ensure security.

  Further, in the object detection sensor of the present invention, the interference determination unit obtains a current detection range from a distance to the object to be measured for each direction obtained from current distance measurement data, and calculates the area of the warning area and the It may be determined that visual field disturbance has occurred based on the area difference from the current detection range.

  As a result, it is possible to determine the occurrence of an obstruction act on the object detection sensor based on the range that can be measured with the current measurement results for the warning area that is set in advance as a range to be guarded for security planning. It is possible to monitor and maintain security.

  The security system according to the present invention is a security system comprising an object detection sensor for monitoring an inside of a warning area and detecting an object in the warning area, and a security device for monitoring an area including the warning area. The object detection sensor includes a storage unit that stores the warning area in advance and periodically scans the warning area to generate distance measurement data indicating a distance to the object to be measured in each direction in the warning area. A detection unit that compares the current ranging data and the alert area to determine whether or not visual field disturbance has occurred, a first communication unit connected to a security device, and the periodic A reference data generation unit that generates reference data for each direction in the alert area based on distance measurement data when an input of a guard start signal is received from the guard device after scanning starts, and the current distance measurement data and the reference data An intrusion determination unit that determines whether or not an intruding object is present, and the security device provides a security set mode for reporting an abnormality in the area to a remote monitoring center and an abnormality in the area to the monitoring center. A mode setting unit that sets a security release mode that does not report, and a second communication unit that transmits a security start signal to the object detection sensor when the security set mode is set. .

  According to the present invention, by using different comparison information depending on the abnormality of the detection target, even in an outdoor environment where the position and movement of an object can change daily, security planning from the sensor characteristics and detection range By detecting the relative deviation between the warning area preset as the upper warning range and the current measurement result, it becomes possible to maintain and ensure security, and from the distance measurement data at a predetermined time By comparing the generated reference data with the current measurement result, it is possible to detect an intruding object that enters the reference data using the reference data dynamically corresponding to an environment that can be changed every day.

It is the schematic which shows the whole structure of the security system of this invention. It is a block diagram which shows the structure of the object detection sensor of this invention. It is a block diagram which shows the structure of the security apparatus of this invention. It is a figure which shows the outline | summary of the detection method of the obstruction | occlusion area | region by the object detection sensor of this invention, and the detection method of an intruding object. It is a figure which shows the intruder determination process by the object detection sensor of this invention. It is a flowchart which shows operation | movement of the object detection sensor of this invention. It is a flowchart which shows the visual field disturbance determination process by the object detection sensor of this invention. It is a flowchart which shows the intruder determination process by the object detection sensor of this invention.

Embodiments of the present invention will be specifically described below with reference to the drawings.
In the present embodiment, a security system that performs outdoor monitoring using an object detection sensor in a monitoring building is illustrated, but the scope of the present invention is not limited to this.

FIG. 1 is a configuration diagram showing a security system 1 using an object detection sensor 2 of the present invention.
FIG. 1 is a schematic plan view showing the relationship between an object detection sensor 2 installed on an outdoor wall surface of a monitoring building 3, a warning area 4 of the object detection sensor 2, and a security device 5 installed in the monitoring building 3. It is shown on the figure. In the example of FIG. 1, three object detection sensors 2 are installed around the monitoring building 3. The object detection sensors 2 are each connected to the security device 5 via a communication line, and the security device 5 is connected to a remote monitoring center 6 via a communication line network 7. Although not particularly illustrated, security sensors such as a heat ray sensor and an open / close sensor are also installed inside the monitoring building 3 and connected to the security device 5.

  The object detection sensor 2 is present in the area by performing spatial scanning at a predetermined cycle while irradiating a laser beam in a preset warning area 4 and receiving reflected light reflected by an object on the optical path. The position of an object as an object to be measured is detected. In this way, the object detection sensor 2 monitors an object appearing in the alert area 4 and outputs a detection signal indicating the type of abnormality that has occurred and its own address information to the security device 5 when it is determined that an abnormality has occurred.

  Here, the types of abnormalities detected by the object detection sensor 2 include visual field obstruction abnormality due to an obstructing object and invasion abnormality due to an intruding object into the alert area 4 such as a suspicious person. The visual field disturbance abnormality is impaired by the object (including a person) existing in the warning area 4 so that the field of view of the object detection sensor 2 to be originally secured, that is, the state where the laser light irradiation can be performed on the entire warning area 4 is performed. This is an abnormality that is determined when a blind spot of a certain level or more occurs in the alert area 4 due to the obstruction of the laser beam by the object. The intrusion abnormality is an abnormality that is determined when a moving object intrudes into the alert area 4 and the maintenance of the surveillance area including the surveillance building 3 can be impaired.

  The security device 5 monitors the inside and outside of the monitoring building 3 serving as a monitoring area. Then, the security device 5 determines the abnormality of the monitoring area based on the detection signal of the object detection sensor 2 and outputs an abnormality signal to the monitoring center 6.

  The monitoring center 6 is a facility provided with a center device 61 operated by a security company or the like. The center device 61 is composed of one or a plurality of computers, and realizes the function of the monitoring center 6 related to the present invention. In the monitoring center 6, various devices are controlled by the center device 61, the abnormality signal received from the security device 5 is recorded, information on the abnormality is displayed on the display 62, and a plurality of monitoring areas to be monitored by the monitor are displayed. Monitoring.

<Object detection sensor>
Next, the configuration of the object detection sensor 2 will be described with reference to FIG. FIG. 2 is a block diagram showing a configuration of the object detection sensor 2.
The object detection sensor 2 is installed on the outdoor wall surface of the monitoring building 3 with a horizontal or constant depression angle, and operates by receiving power supply from the security device 5.

  The object detection sensor 2 is composed of a communication unit 21 connected to the security device 5 for communication, a detection unit 22 for irradiating and receiving laser light, and a storage unit configured to store various setting information, programs, and the like. 23 and a control unit 24 that is configured by an MPU, a microcomputer, and the like and controls each unit.

  The communication unit 21 is connected to the security device 5, receives a security start signal and a security release signal output from the security device 5, and outputs the signals to the control unit 24. In addition, when the control unit 24 determines that the abnormality in the alert area 4 is detected, the communication unit 21 transmits a detection signal indicating the abnormality information and its own address information to the security device 5.

  The detection unit 22 scans the alert area 4 with a laser beam and detects the position of an object as a measurement object that reflects the laser beam. The detection unit 22 includes, for example, a laser oscillation unit 221 that emits near-infrared light having a wavelength of about 890 nm, a scanning mirror 222 that reflects laser light and irradiates the object detection sensor 2, and scanning that drives the scanning mirror 222 to rotate at a constant speed. A control unit 223, a reflected light detection unit 224 that includes a light receiving element and is provided in the vicinity of the laser oscillation unit 221, and a distance measurement data generation unit 225 that generates distance measurement data as a laser light irradiation result are provided.

  The irradiation direction of the laser light emitted from the laser oscillation unit 221 is controlled by the scanning mirror 222 and the scanning control unit 223 to scan at least the entire warning area 4. This scanning can be performed on a horizontal plane according to the installation angle of the object detection sensor 2 or on a plane that approaches the ground as the distance increases with a depression angle. The scanning is performed at a predetermined cycle interval (for example, 30 msec). For example, the scanning may be repeatedly performed in the same direction, or the backward scanning may be performed after scanning in the forward direction.

  The distance measurement data generation unit 225 determines the distance between the object detection sensor 2 calculated from the time required from the irradiation of the laser light to the detection of the reflected light and the object (measurement point) reflecting the laser light, and the scanning control unit 223. The relative position of the object that reflects the laser beam, that is, the measurement point that reflects the laser beam, is calculated based on the angle of the scanning mirror 222 that is rotationally driven (the direction in the alert area 4). The relative position is the position of the measurement point with reference to the object detection sensor 2, and specifically, the position of the surface that reflects the laser beam on the object. In addition, if the reflected light does not return within a predetermined time, the distance measurement data generation unit 225 determines that there is no object within the distance that can be irradiated with the laser light, and records the predetermined pseudo data as a relative position. To do. The pseudo data may be a predetermined value, for example, a distance value that is an outer periphery of the alert area 4 to be monitored by the object detection sensor 2 or an appropriate value that is equal to or greater than an effective measurement distance by laser light.

The measurement data obtained by the distance measurement data generation unit 225 is referred to as distance measurement data in this embodiment. The distance measurement data is specifically the result of measuring the alert area 4 at a predetermined angular interval (for example, 0.25 °) by one scan by the detection unit 22. For example, when distance measurement data is acquired at intervals of 0.25 ° for a range of 180 °, 721 distance values are obtained. A set of these 721 distance values becomes one distance measurement data. The distance measurement data may be stored as a table of angles (directions) and distances.
The distance measurement data generation unit 225 generates distance measurement data and outputs it to the control unit 24 every time one scan of the detection unit 22 ends at a predetermined cycle interval (for example, 30 msec).

  The storage unit 23 is configured by a ROM, a RAM, or an HDD, stores address information for identifying itself, various programs, and the like, and further stores various information for operating the object detection sensor 2. Specifically, the storage unit 23 includes warning area information indicating the set warning area 4, reference data generated by the control unit 24, object tracking information detected by the detection unit 22, Current state information indicating the state of the alert area 4 is stored. The storage unit 23 stores distance measurement data for the past predetermined period output from the detection unit 22.

The warning area information is information indicating the warning area 4 set according to the security planning of the monitoring area by a security company or the like as a range to be monitored by the object detection sensor 2, for example.
The warning area information is input by designating a range on the scanning plane by the detection unit 22 from a setting terminal, an operation unit (not shown), or the like when the object detection sensor 2 is installed or when security planning of the monitoring area is changed. The range of the warning area 4 that is input is associated with an angle (direction) from the detection unit 22 and a distance value for each predetermined angular interval (for example, 0.25 °) scanned by the detection unit 22. It is stored in the storage unit 23 as a table of angles (directions) and distances. In the present embodiment, as shown in FIG. 1, an example in which the alert area 4 is set in a semicircular shape centering on the object detection sensor 2 will be described.
Note that the alert area information is not limited to this, and it is only necessary to store the positional relationship between the information indicating the range of the alert area 4 and the object detection sensor 2 so that the object detection sensor 2 can be identified. It may be set and stored in two-dimensional coordinates indicating a simple positional relationship.

  The reference data is comparison reference information used for extracting an intruding object that has newly appeared in the alert area 4 in comparison with the current distance measurement data in an intrusion determination process described later. Is generated from distance measurement data acquired at any past time from the current to the present. The reference data may be stored as a table of angles (directions) and distances. Further, the reference data may be generated at any past time point, and may be updated using distance measurement data acquired at any time. In the present embodiment, an example will be described in which reference data is generated and stored from distance measurement data acquired by the first scan after the detection unit 22 starts scanning.

  The tracking information is information used for tracking an intruding object newly appearing in the alert area 4 in a later-described intrusion determination process over a plurality of periods. In the tracking information, the position and size of the intruding object in the current period, and the position and size of the intruding object that first appeared in the alert area 4 are stored in association with each other.

  In the current state information, whether the current warning area is normal as a result of determination by the control unit 24, or whether a visual field disturbance abnormality due to an obstructing object or an intrusion abnormality due to an intruding object such as a suspicious person has occurred. Remembered. When the controller 24 determines that such an abnormality has occurred, the state of each abnormality is stored, and when it is determined that the abnormality has disappeared, it is stored that it is normal.

  The control unit 24 includes a microcomputer including a CPU, a ROM, a RAM, and the like and peripheral circuits thereof, and controls the above-described units. For this purpose, the control unit 24 determines whether there is a visual field disturbance abnormality and a drive control unit 241 that controls the driving of the detection unit 22 as functional modules realized by the microcomputer and a computer program executed on the microcomputer. A disturbance determination unit 242 that performs the detection, a reference data generation unit 243 that generates reference data from the distance measurement data acquired by the detection unit 22, and an intrusion determination unit 244 that determines whether there is an intrusion abnormality.

The drive control unit 241 outputs a drive signal to the detection unit 22 when a security start signal is input from the security device 5 via the communication unit 21, starts driving the detection unit 22, and is scanned by the scan control unit 223. Driving of the mirror 222 and irradiation of laser light by the laser oscillation unit 221 are started. In addition, when a security release signal is input from the security device 5, the drive control unit 241 outputs a drive stop signal to the detection unit 22, stops driving the detection unit 22 at the end of scanning at that time, and scans a mirror 222. Is stopped and laser beam irradiation is stopped.
Thus, it becomes possible to prevent breakage of the drive parts due to continuous operation by driving the detection unit 22 in accordance with the start of security of the security device 5.

  The disturbance determination unit 242 compares the current distance measurement data acquired by the detection unit 22 with the warning area information stored in the storage unit 23 to determine whether or not the visual field disturbance abnormality has occurred. As described above, the warning area 4 is an area set as a range to be monitored by the object detection sensor 2, and the object detection sensor 2 irradiates the entire area of the warning area 4 with laser light in order to ensure security. Must be in a state where However, in the outdoor environment, there is a possibility that installations such as planting growth and buds, flying objects from the wind, and fences installed by users in the monitoring area may appear in the monitoring area. It becomes difficult to keep the state of 4 constant. For this reason, in the present embodiment, the interference determination unit 242 has the current distance measurement that is a warning area 4 set in advance as a range to be monitored by the object detection sensor 2 and the line-of-sight distance from the object detection sensor 2 in each direction. By comparing with the data, it is determined whether or not a certain blind spot has occurred in the alert area 4, and it is monitored whether an effective monitoring field of view is secured.

Specifically, the interference determination unit 242 compares the distance value for each scanning angle obtained from the distance measurement data with the angle indicating the range of the warning area 4 and the distance value for each corresponding angle, and 4, an area that cannot be measured by being obstructed by an object (hereinafter referred to as an occlusion area) is calculated, and when the area of the occlusion area exceeds a predetermined ratio (for example, ½) with respect to the area of the alert area 4, It is determined that the visual field obstruction abnormality has occurred, assuming that the monitoring visual field 2 is obstructed.
When it is determined that the visual field disturbance abnormality has occurred, the visual field disturbance abnormality is stored in the current state information of the storage unit 23, and when it is determined that the visual field disturbance abnormality has not occurred, the information on the abnormality is deleted from the current state information. The

This will be described in more detail with reference to FIG. The method for calculating the area of the blocking area by the blocking determination unit 242 is shown on the left side of FIG. In the example of the figure, the distance from the object detection sensor 2 to the measurement point (reflection point by the object) at a certain scanning angle is dn, and the distance to the outer periphery of the alert area 4 stored in the alert area information is d. Therefore, when the outer periphery of the alert area 4 is set as an arc as shown in the figure, if the scanning angle interval is 0.25 °, the area of the blocking area in one scanning angle unit is π (d ² − dn ² ) 0.25 / 360. At this time, if the measurement point is obtained outside the alert area 4, that is, if the laser beam passes through the alert area 4, the distance dn to the measurement point is simulated as the distance d to the outer periphery of the alert area 4. To calculate the area (if dn> d, dn = d).
In this way, the disturbance determination unit 242 calculates the area of the blocking region using the distance value dn and the distance d to the outer periphery of the warning region 4 for each scanning angle, and the entire scanning range (for example, 180) of the detection unit 22. The area of the shielding area in the alert area 4 is calculated by adding up to (°). Then, the presence / absence of the visual field disturbance abnormality is determined by comparing the area of the shielding area and the area of the warning area 4.

The reference data generation unit 243 generates reference data using the distance measurement data acquired from the detection unit 22. As described above, in the present embodiment, an example will be described in which the reference data is generated and stored from the distance measurement data acquired in the first scan after the scanning by the detection unit 22 is started. That is, when the drive signal is output from the drive control unit 241 and scanning of the detection unit 22 is started, the reference data generation unit 243 stores the distance measurement data output in the first scan in the storage unit 23 as reference data. To do. When the distance value corresponding to a certain angle is not within the warning area 4 as the position of the measurement point in the distance measurement data, the distance to the outer periphery of the warning area 4 corresponding to the angle may be stored as reference data. Since the distance to the measurement point by the scanning is stored in the reference data, existing objects such as planting and outer walls existing in the alert area 4 at the time of the scanning are taken in as the reference data.
However, the present invention is not limited to this, and the reference data generation unit 243 determines the distance value for each scanning angle in the distance measurement data a predetermined number of times (for example, scanning performed for 5 minutes) after the detection unit 22 starts scanning. The frequency may be obtained, and the distance value with the highest frequency may be adopted as the reference value of the scanning angle to generate reference data.

  The intrusion determination unit 244 compares the current distance measurement data with the reference data to determine whether there is an intruding object that has appeared in the alert area 4, and determines whether an intrusion abnormality has occurred based on the movement of the intruding object. As described above, there are many moving objects such as small animals in the outdoor environment compared to indoors, and there may be shaking such as planting and flying objects due to the wind. Therefore, a new object (intruding object) is present in the alert area 4. It can be erroneously determined to be an intrusion abnormality that can immediately impair the maintenance of the monitored area just by the appearance of. For this reason, in this embodiment, when the intrusion determination unit 244 detects an intruding object that has appeared in the alert area 4, the intruding object is evaluated over a plurality of periods, and an intrusion abnormality caused by a suspicious person or a suspicious vehicle occurs. It is determined whether or not.

Specifically, the intrusion determination unit 244 calculates, for each corresponding angle, the difference between the distance value for each scanning angle obtained from the distance measurement data and the distance value for each angle stored in the reference data. The presence of an intruding object is determined based on a measurement point that is closer than the data. Then, referring to the tracking information, it is determined whether or not there is an object corresponding to the intruding object in the detection result of the previous cycle, and when there is the corresponding object, the position where the intruding object first appears in the alert area 4 If the moving distance from the current position to the current position is equal to or longer than a predetermined distance (for example, 1 m), it is determined that an intrusion abnormality has occurred due to the intruding object. The tracking information stores the position and size of the object detected in the current cycle.
When it is determined that an intrusion abnormality has occurred, the intrusion abnormality is stored in the current state information of the storage unit 23, and when it is determined that no intrusion abnormality has occurred, the information on the abnormality is deleted from the current state information.

  This will be described in more detail with reference to FIGS. An intruding object detection method by the intrusion determination unit 244 is shown on the right side of FIG. As shown in the figure, the object Q is detected as an intruding object when the distance dn to the current measurement point is shorter than the distance db to the measurement point (reflection point by the object) stored in the reference data at a certain scanning angle. Is done.

FIG. 5 shows the concept of the intruder determination process based on comparison of distance measurement data. In FIG. 5, the horizontal axis is an angle, and the vertical axis is a distance value corresponding to an angle component. The intrusion determination unit 244 calculates a difference in distance value for each angle component between the current distance measurement data and the reference data, and the change point where the current distance measurement data is closer than the reference data by a predetermined distance or more. Check for presence. The change point is a point where the distance difference is a negative value and is −Δ or less (a point where the distance difference is Δ or more on the − side) in the lower diagram of FIG. 5. If there is a change point, the intrusion determination unit 244 examines the continuous section and labels the continuous sections. At this time, non-continuous change points (isolated points) may be removed as noise, and integration or noise removal by expansion / contraction processing may be performed. If the size of the labeled object is equal to or larger than a predetermined size (for example, 15 cm) that can be determined as a part of a suspicious person or a suspicious vehicle, the intrusion determination unit 244 detects the object as an intruding object.
Then, the intrusion determining unit 244 checks the association between the detected intruding object and the detected object in the previous cycle, and determines whether or not an intrusion abnormality has occurred based on the movement distance from the position where it first appeared in the alert area. .

<Security device>
Next, the configuration of the security device 5 will be described with reference to FIG. FIG. 3 is a block diagram showing the configuration of the security device 5. The security device 5 is installed in the monitoring building 3 and vigilancely monitors the monitoring area, and notifies the remote monitoring center 6 of the location of the abnormality.

  The security device 5 includes a sensor I / F (interface) 51 connected to the object detection sensor 2 and other security sensors (not shown), and a communication unit 52 connected to the remote monitoring center 6 via the communication network 7. And an operation unit 53 operated by a user in the monitoring area, a storage unit 54 composed of an HDD, a memory, and the like, and a control unit 55 composed of an MPU, a microcomputer, etc. and controlling each unit. Composed. The control unit 55 includes, as function modules, a mode setting unit 551 that sets / changes the security mode of the monitoring area and an abnormality processing unit 552 that determines that an abnormality has occurred in the monitoring area. The storage unit 54 stores management information such as security mode information and current state information, various processing programs and parameters, identification information of the security device 5, and the like.

  The mode setting unit 551 collates information input from the operation unit 53 when the user sets the security mode, and if the verification is OK, the security mode is set to the security set mode or the security release based on the input of the operation unit 53. Set to mode. The security mode set by the mode setting unit 551 is stored in the security mode information of the storage unit 54.

Here, the security set mode is set when the monitoring area including the monitoring building 3 becomes unmanned, such as at night or on a holiday, and the remote monitoring center 6 is connected via the communication unit when various sensors detect a change in the event. This is a mode to send an error report to. Further, the security release mode is a mode that is set when the monitoring area is manned and does not perform abnormality notification by detection of various sensors.
The mode setting unit 551 outputs a security start signal to the object detection sensor 2 via the sensor I / F 51 when set to the security set mode, and via the sensor I / F 51 when set to the security release mode. A security release signal is output to the object detection sensor 2.

  When the current security mode stored in the storage unit 54 is the security set mode, the abnormality processing unit 552 determines that an abnormality has occurred in the monitoring area when receiving detection signals from various sensors. In addition, the abnormality type corresponding to the detection signals input from the various sensors and the information of the detected sensors are stored. In addition, when the occurrence of the abnormality is confirmed, the abnormality processing unit 552 transmits an abnormality signal including the sensor detected as the abnormality type and the identification information of the security device 5 to the remote monitoring center 6 via the communication unit 52.

<Description of operation>
About the security system 1 comprised as mentioned above, the operation | movement is demonstrated with reference to drawings. Here, an operation related to the object detection sensor 2 will be mainly described. FIG. 6 is a flowchart showing the operation of the monitoring program executed by the object detection sensor 2.

  The drive control part 241 will output a drive signal to the detection part 22, if the security start signal is received from the security apparatus 5 (step ST1-Yes), and will start the drive of the detection part 22 (step ST2). When the detection unit 22 receives the drive signal and starts scanning the alert area 4 and the distance measurement data is output (step ST3-Yes), the reference data generation unit 243 converts the distance measurement data obtained by the first scan into the distance measurement data. Based on this, reference data is generated and stored in the storage unit 23 (step ST4).

  When the distance measurement data is acquired after generating the reference data (step ST5-Yes), the disturbance determination unit 242 compares the current distance measurement data with preset warning area information, and the visual field disturbance determination process. Is performed (step ST6). The visual field disturbance determination process will be described later. Note that the visual field disturbance determination process can be executed even with the distance measurement data used for generating the reference data, so that the process is skipped to skip step ST5 for the first time or until the reference data is generated, and the visual field disturbance determination is performed. Processing may be performed.

  In step ST7, the intrusion determination unit 244 performs the intrusion determination process by comparing the current distance measurement data with the reference data. The intrusion determination process will be described later. And if the abnormal information which is not output to the security device 5 is memorize | stored in the present condition information of the memory | storage part 23 based on the result of a visual field disturbance determination process and an intrusion determination process (step ST8-Yes), it will start from the communication part 21 A detection signal indicating abnormality information and own address information is transmitted to the security device 5 (step ST9).

  If the object detection sensor 2 has not received a security release signal from the security device 5 (step ST10-No), the process of steps ST5 to ST9 is repeated to monitor the security area 4. On the other hand, when a security release signal is received from the security device 5 (step ST10-Yes), the drive control unit 241 outputs a drive stop signal to the detection unit 22 to stop driving the detection unit 22 (step ST11), and the storage unit The abnormality information stored in the current state information 23 is deleted, the state becomes normal (step ST12), and the series of processing ends. In step ST3 and ST5, if distance measurement data is not acquired even after exceeding a predetermined scanning period (for example, 30 msec), the process may be terminated as a device abnormality.

The basic operation of the object detection sensor 2 has been described above.
Next, the visual field disturbance determination process in step ST6 of FIG. 6 will be described with reference to FIG. FIG. 7 is a flowchart of the visual field disturbance determination process.

In FIG. 7, the disturbance determination unit 242 reads the distance measurement data and the warning area information acquired in the current cycle (step ST21), and stores the distance value d stored as the warning area information for each angle component (direction) and the current value. Are compared with the distance value dn detected from the distance measurement data, and the blocking area by the blocking object detected as the measurement point is calculated (step ST22). For example, as shown on the left side of FIG. 4, when the scanning angle interval is 0.25 ° and the outer periphery of the alert area 4 is set as an arc, the area of the shielding area for one angle component is π (d ²⁻ dn ² ) 0.25 / 360 (provided that dn = d if dn> d).

Then, the disturbance determination unit 242 calculates the blocking area of the entire scanning range (for example, 180 °) by adding all the blocking areas calculated for each angle component (direction) (step ST23). In step ST24, the interference determining unit 242 determines whether or not the calculated blocked area is equal to or greater than a predetermined ratio (for example, 1/2) with respect to the area of the alert area 4, and if this is satisfied (step ST24). -Yes), it is determined that the visual field disturbance abnormality has occurred in the alert area 4, and the visual field disturbance abnormality is stored in the current state information of the storage unit 23 (step ST25). As a result, a detection signal is output to the security device 5 in step ST9 of FIG. 6, and when the abnormality is confirmed by the security device 5, an abnormality is notified to the remote monitoring center 6.
On the other hand, if the calculated blocking area does not reach a predetermined ratio with respect to the area of the alert area (step ST24-No), it is determined that there is no visual field obstruction and the process is terminated. At this time, if the visual field disturbance abnormality is stored in the current state information, the abnormality information is deleted.

  If it is determined in step ST24 that the blocking area is equal to or greater than a predetermined ratio (for example, ½) with respect to the area of the warning area 4, the blocking determination unit 242 stores this as current cycle information in the storage unit 23. Then, when it is determined that the shielding area is equal to or larger than the predetermined ratio with respect to the area of the alert area 4 continuously for a predetermined time or a plurality of periods, a process for determining that the visual field disturbance abnormality has occurred in step ST25 is performed. May be.

In this way, the interference determination unit 242 compares the warning area 4 set in advance as a range to be monitored by the object detection sensor 2 with the current distance measurement data that is the line-of-sight distance from the object detection sensor 2. By doing so, it is determined whether or not a blind spot of a certain level or more is generated in the alert area 4, and it is monitored whether an effective monitoring field of view is secured. When the blind spot that cannot be monitored in the alert area 4 becomes a certain (for example, area ratio 1/2) or more, it is determined that the monitoring field of view is obstructed.
As a result, even in an outdoor environment where it is difficult to keep the state of the alert area 4 in a certain state due to the effects of planting growth, new installations, etc., it is set as a range to be alerted for security planning. It becomes possible to evaluate the monitoring range by the object detection sensor 2 based on the relative range that cannot be measured with the current measurement result with respect to the alert area 4, and detect a situation where the monitoring capability is impaired, and security It is possible to ensure maintenance.

  Next, the intrusion determination process in step ST7 of FIG. 6 will be described with reference to FIG. FIG. 8 is a flowchart of the intrusion determination process.

  In FIG. 8, the intrusion determination unit 244 reads the distance measurement data and the reference data acquired in the current cycle (step ST31), and the distance value detected from the current distance measurement data for each angle component (direction). The difference between dn and the distance value db stored in the reference data is calculated (step ST32).

  Then, the intrusion determination unit 244 checks whether there is a change point where the current distance measurement data is closer than the reference data by a predetermined distance or more from the difference result between the current distance measurement data and the reference data (step ST33). ). The change point is a point where the distance difference is a negative value and is −Δ or less (a point where the distance difference is Δ or more on the − side) in the lower diagram of FIG. 5. If there is a change point (Yes in step ST33), the intrusion determination unit 244 examines the continuous section, labels the consecutive change points that are close in distance, and detects them as an intruding object (step ST34). Here, since the angular interval when the detection unit 22 scans is sufficiently close compared to the detection target object (such as a person or a vehicle), the change points (isolation points) that are not continuous or the size of the labeling are not observed. An object that is smaller than a predetermined size (for example, 15 cm) that can be determined as a part of a detection target object (such as a person or a vehicle) may be removed as noise.

  The intrusion determination unit 244 stores the position (angle and distance value) of the measurement point included in the label detected as the intruding object in the tracking information of the storage unit 23 as current cycle information (step ST35). Then, the intrusion determination unit 244 compares the processing results of the previous cycle and the current cycle with reference to the tracking information, and determines whether there is a tracking target for each label (step ST36). In the tracking process, the presence / absence of a tracking target is determined based on whether or not there are objects of substantially the same size within a predetermined angle and distance range between the previous cycle and the current cycle. If there is a corresponding object, that object becomes the tracking target. If there is no tracking target (step ST36-No), the label of the current cycle is stored in the tracking information of the current cycle as a newly appearing label, and the intrusion determination process ends.

  When the tracking target exists (step ST36-Yes), the intrusion determination unit 244 reads the position and size when the label of the corresponding previous period newly appears in the alert area 4 from the tracking information, and enters the alert area 4 The moving distance from the newly appearing position to the current position is calculated (step ST37). The movement distance is calculated from the straight line distance from the newly appearing position to the current position.

  If the calculated moving distance is less than a predetermined distance (for example, 1 m) (step ST38-No), the label of the previous cycle and the corresponding label of the current cycle are linked and stored in the tracking information of the current cycle, The position and size when newly appearing in the alert area 4 and the current position and size are associated with each other, and the intrusion determination process is terminated. On the other hand, if the calculated moving distance is equal to or greater than a predetermined distance (for example, 1 m) (step ST38-Yes), it is determined that an intrusion abnormality has occurred due to the corresponding label (intruding object), and the current state information in the storage unit 23 is intruded. The abnormality is stored (step ST39). As a result, a detection signal is output to the security device 5 in step ST9 of FIG. 6, and when the abnormality is confirmed by the security device 5, an abnormality is notified to the remote monitoring center 6.

As described above, the intrusion determination unit 244 determines whether or not there is an intruding object that has appeared in the alert area 4 by comparing the reference data acquired as past distance measurement data with the current distance measurement data.
This enables the detection of intruding objects that enter the environment using reference data that dynamically responds to environmental changes, even when monitoring outdoor environments where the environment may change daily, such as new installations and planting growth. It becomes possible.
In addition, by determining the occurrence of an intrusion abnormality based on the movement of an intruding object, it is possible to prevent erroneous determination due to an object that temporarily appears in the alert area 4 due to the influence of small animals, planting, wind, etc. It is possible to detect an intrusion by a suspicious person or a suspicious vehicle that may damage the vehicle.

  The embodiments of the present invention have been described above by way of example, but the scope of the present invention is not limited to these embodiments, and can be changed or modified according to the purpose within the scope of the claims. is there.

For example, in the above-described embodiment, the example in which the visual field disturbance abnormality is determined from the area of the shielding area that cannot be monitored in the warning area 4 is described. However, the present invention is not limited thereto, and the current measurable range that can be monitored in the warning area 4 The presence / absence of the visual field obstruction act on the object detection sensor 2 may be determined based on the above. In this case, the interference determination unit 242 calculates an area (area where there is no reflecting object and the laser beam passes) calculated from the distance value dn for each scanning angle obtained from the current distance measurement data, and calculates this over the entire scanning range. (For example, 180 °) is added to calculate the area of the current measurable range (provided that dn = d if dn> d). Then, the calculated area of the measurable range and the area of the alert area 4 are compared, and if the area of the present measurable range is less than a predetermined ratio (for example, 1/2) with respect to the area of the alert area 4, the visual field disturbance It is determined that an abnormality has occurred.
This also makes it possible to evaluate the monitoring range by the object detection sensor 2 based on the relative range of the current measurement result with respect to the warning area 4 set as a warning range in the security planning, and the monitoring capability is impaired. It is possible to detect and maintain security and maintain security.

  Moreover, although this embodiment demonstrated the example which receives the guard start signal and the guard cancellation | release signal from the guard apparatus 5, and drives the detection part 22 while the guard apparatus 5 is set to the guard set mode, It is not limited to. That is, the detection unit 22 may be constantly driven. In this case, step ST1 in FIG. 6 may be omitted, and the determination in step ST10 may be a determination as to whether a predetermined drive end signal has been input.

In addition, weight information can be stored in the storage unit 23 for each scanning angle (direction in the alert area) of the detection unit 22, and the interference determination unit 242 can calculate the blocking area using the weight information. It is. That is, the interference determination unit 242 performs weighting according to the scanning angle on the blocking area calculated from the distance for each scanning angle obtained from the current distance measurement data.
As a result, an important monitoring direction is obtained by multiplying the blocking area calculated for the important direction by a count of 1 or more as a weight according to an important object or an important section existing in the direction monitored by the object detection sensor 2. As a result, it is possible to easily detect a situation in which an important monitoring target cannot be monitored, and to improve security.

  Further, in the present embodiment, the example in which the tracking process is performed with the distance measurement data one cycle before (previous cycle with respect to the current cycle) in the intrusion determination process illustrated in FIG. 8 is described. A tracking process may be performed between distance measurement data within a predetermined time (for example, data acquired during one second). In this case, it is determined whether or not association is possible for all the distance measurement data acquired within a predetermined time in the tracking process, and if there is a corresponding label, it is determined that there is a tracking target. Thereby, even if it is a case where detection is missing by instantaneous noise, it is possible to detect the tracking target without erroneous determination.

DESCRIPTION OF SYMBOLS 1 Security system 2 Object detection sensor 21 Communication part 22 Detection part 221 Laser oscillation part 222 Scanning mirror 223 Scanning control part 224 Reflected light detection part 225 Distance measurement data generation part 23 Storage part 24 Control part 241 Drive control part 242 Interference determination part 243 Reference data generation unit 244 Intrusion determination unit 3 Surveillance building 4 Warning area 5 Security device 51 Sensor I / F
52 communication unit 53 operation unit 54 storage unit 55 control unit 551 mode setting unit 552 abnormality processing unit 6 monitoring center 7 communication network

Claims (6)

An object detection sensor for monitoring an inside of a warning area and detecting an object in the warning area,
A storage unit for storing the warning area in advance;
A detection unit that periodically scans within the alert area and generates distance measurement data indicating a distance to the object to be measured for each direction in the alert area;
A disturbance determination unit that determines the presence or absence of visual field disturbance by comparing the current ranging data and the alert area;
A reference data generation unit that generates reference data for each direction in the alert area based on distance measurement data at a predetermined time after the start of periodic scanning;
An intrusion determination unit that determines the presence or absence of an intruding object by comparing the current ranging data and the reference data;
An object detection sensor comprising:
And a communication unit connected to a security device for monitoring a monitoring area including the warning area,
The detector is
The scanning is started when an input of a security start signal is received from the security device, and the scanning is terminated when an input of a security release signal is received from the security device,
The reference data generation unit
The object detection sensor according to claim 1, wherein reference data for each direction in the security area is generated based on distance measurement data when a security start signal is received from the security device.
The storage unit
The object detection sensor according to claim 1, wherein the warning area is stored as two-dimensional information including a distance and a direction from the detection unit.
The interference determination unit is
A distance difference between the distance stored as the alert area for each direction and the distance to the object to be measured obtained from the current distance measurement data is obtained, and the measured area in the alert area is determined from the distance difference for each direction. The object detection sensor according to any one of claims 1 to 3, wherein an obstruction area that is obstructed by an object is calculated, and if the obstruction area is equal to or greater than a predetermined ratio with respect to the area of the alert area, it is determined that visual field obstruction occurs. .
The interference determination unit is
The current detection range is obtained from the distance to the object to be measured in each direction obtained from the current distance measurement data, and it is determined that visual field disturbance has occurred based on the area difference between the area of the warning area and the current detection range The object detection sensor according to any one of claims 1 to 3.
A security system comprising an object detection sensor for monitoring an inside of a warning area and detecting an object in the warning area, and a security device for monitoring an area including the warning area,
The object detection sensor is
A storage unit for storing the warning area in advance;
A detection unit that periodically scans within the alert area and generates distance measurement data indicating a distance to the object to be measured for each direction in the alert area;
A disturbance determination unit that determines the presence or absence of visual field disturbance by comparing the current ranging data and the alert area;
A first communication unit connected to the security device;
A reference data generation unit that generates reference data for each direction in the alert area based on distance measurement data when receiving an input of a guard start signal from the guard device after the periodic scan starts;
An intrusion determination unit that determines the presence or absence of an intruding object by comparing the current ranging data and the reference data;
With
The security device
A mode setting unit for setting a security set mode for reporting an abnormality of the area to a remote monitoring center and a security release mode for not reporting the abnormality of the area to the monitoring center;
A second communication unit that transmits a security start signal to the object detection sensor when the security set mode is set;
Security system characterized by comprising.

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