JP2000266848A - Fog whistling device and fog whistling method - Google Patents

Abstract

(57) [Problem] To realize a fog whistle sounding device and a fog whistle sounding method capable of automatically sounding a fog whistle even in an unmanned lighthouse by monitoring the fog distribution on the sea in a three-dimensional or three-dimensional manner by a radar device. I do. SOLUTION: A fog whistling device for notifying the occurrence of fog in a monitoring area by fog whistling, a radar device 1 for observing the distribution of fog generated within the monitoring region, and a necessity of fog whistling according to observation data. Fog whistling determination means 2 for determination;
A fog whistle 3 that sounds based on the result of the determination by the fog whistling determination means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is, for example, installed in a lighthouse or the like, and automatically detects fog distribution occurring on the sea and automatically blows a fog whistle to notify a fog occurrence to a ship or the like, thereby ensuring safety of navigation at sea. Fog flute device and fog flute method.

[0002]

2. Description of the Related Art Deterioration of visibility due to fog is caused by land traffic,
It greatly reduces the safety of maritime traffic and takeoff and landing of aircraft.
Therefore, fog monitoring is an important issue for ensuring traffic safety. Conventionally, fog has been monitored by, for example, a television camera or a visibility meter using a laser. However, with these fog sensors, it is possible to observe the fog at the sensor installation position, but in order to measure the fog distribution (two-dimensional and three-dimensional spread of the fog), it is necessary to arrange a plurality of sensors. was there. In particular, since it is difficult to always dispose a fog sensor on the sea, fog monitoring can be performed only by visual observation from the land or by a fog sensor on a ship.

A lighthouse is usually installed at the cape, and when visibility is good, the lighthouse informs the ship of the land position,
When the visibility is deteriorating due to fog, the ship is informed of the land position by blowing a fog whistle. If the lighthouse can automatically detect fog at sea,
Since it is possible to automatically perform fog whistling when visibility is poor, the lighthouse can be unmanned.

[0004] As an apparatus that automatically operates as described above, for example, in Japanese Patent Application Laid-Open No. 49-121384, an apparatus that switches a light source of a light projector of a lighthouse when a dense fog is detected by a sensor installed in the lighthouse. Is described. Also, Japanese Patent Application Laid-Open No. 60-14299 describes a device that includes a fog in-flight state detection unit on a ship and automatically generates a fog in-flight signal from the ship when fog is detected by the in-fog state detection unit. . Although these two devices are different in whether they are installed in a lighthouse or on a ship, both of them detect fog only at the place (point) where the device exists. However, the information required for ensuring the safety of the operation of the ship is the fog distribution in a wide area where the ship travels. Therefore, the fog detection method of the related art does not perform satisfactory fog monitoring.

[0005]

At present, in a lighthouse, fog is monitored by a visibility meter. However, as in the above-described prior art, it is only possible to know the presence of fog only at a certain point of the lighthouse. . Therefore, at present, the fog is monitored by human eyes while deciding whether to blow the fog whistle while referring to the data of the visibility meter. Further, in unmanned lighthouses, the visibility meter cannot be used practically.

[0006] Since it is expected that unmanned lighthouses will continue to be unmanned even in places where manned surveillance is performed in the future, there is an increasing need for automatic sounding of fog whistles in unmanned lighthouses. However, due to the above-mentioned reasons, it is currently impossible to perform visibility observation suitable for automatic blowing of a fog whistle with the visibility measurement by the conventional visibility meter.

The present invention has been made to solve the above problems,
It is an object of the present invention to realize a fog flute apparatus and a fog flute method that can automatically blow a fog flute even in an unmanned lighthouse by monitoring the fog distribution on the sea with a radar device in a two-dimensional or three-dimensional manner.

[0008]

The invention according to claim 1 is
A fog whistling device that notifies the occurrence of fog in the monitoring area by fog whistling, a radar device that observes the distribution of fog generated within the monitoring region, and a fog whistling determination that determines whether fog whistling is necessary according to the observation data Means, and a fog whistle that blows based on the result of the determination by the fog whistling determination means.

According to a second aspect of the present invention, the fog whistling determination means includes a visibility distance distribution calculating means for calculating a visibility distance distribution from observation data of the radar device, and a visibility distance is set in advance in the calculated visibility distance distribution. Bad visibility area calculating means for obtaining a fog distribution area of a region equal to or less than the determined visibility distance threshold, and fog whistling is performed when the obtained fog distribution area is equal to or greater than a preset fog distribution area threshold. It is characterized by comprising a bad visibility area determining means for determining that it is necessary.

According to a third aspect of the present invention, the visibility distance distribution calculating means sets the visibility distance of the observation azimuth beyond the point where observation by the radar device in a certain observation azimuth becomes impossible in the monitoring area to 0. It is characterized by doing.

According to a fourth aspect of the present invention, the visibility range distribution calculating means identifies the observation target based on the observation data observed by the radar device. If the observation target is identified as fog, the observation is stopped. The visibility distance of the observation azimuth beyond the impossible point is set to 0.

According to a fifth aspect of the present invention, there is provided a fog flute sounding device for notifying the occurrence of fog in the monitoring area by the fog sound of the fog whistle, wherein the radar apparatus for observing the distribution of the fog generated in the monitoring area and a satellite for observation. Satellite data acquisition means for capturing observation data of fog distribution, fog flute sound determination means for determining necessity of fog flute sounding according to observation data obtained from the radar device and satellite data acquisition means, and fog whistle sound determination means And a fog whistle blowing based on the determination result.

According to a sixth aspect of the present invention, there is provided a fog flute sounding device for notifying the occurrence of fog in a monitoring area by a fog flute sounding, wherein a radar apparatus for observing the distribution of fog generated in the monitoring area, and And fog information acquisition means for capturing visibility distance data observed by second observation means different from the radar apparatus, and comparing observation data from the radar apparatus with visibility distance data from the fog information acquisition means. A visibility distance correction means for calibrating the observation data, a fog flute sounding judgment means for judging the necessity of fog flute sounding according to the calibrated observation data, and a fog flute sounding based on the judgment result of the fog sounding sound judgment means. It is characterized by having.

According to a seventh aspect of the present invention, there is provided a fog observation step of observing a fog distribution by a radar apparatus, a fog distribution calculating step of calculating a fog distribution from observation data obtained in the fog observation step, and a fog distribution calculating step. From the visibility distance distribution calculation step of obtaining the visibility distance distribution from the fog distribution obtained in step 1, and from the visibility distance distribution obtained in the visibility distance distribution calculation step,
A fog whistling sound determining step of determining that fog whistling is necessary when an area of a region having a visibility distance equal to or less than a predetermined visibility distance threshold is equal to or greater than a predetermined fog distribution area threshold value; A fog whistling step of performing a fog whistling based on the result of the determination in the buzzing determination step.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Hereinafter, an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram of a fog whistling device of the present invention. In FIG.
Reference numeral 1 denotes a radar device for performing fog observation, reference numeral 2 denotes a fog flute sound determining means for determining whether or not fog flute is required based on observation data acquired by the radar device 1, and reference numeral 3 denotes a fog whistle sounding based on the determination result of the fog whistle determination means 2. It is. FIG. 2 is an explanatory view of the operation concept of the fog flute device.

First, fog at sea is monitored by the radar device 1. When observing fog with the radar device, a wide range of fog data is acquired by scanning the aerial of the radar device. As a method of scanning the aerial of a radar device, a PPI (Plan Position I) that rotates in an azimuth direction while fixing an elevation angle is used.
ndicator) scanning is typical. If the fog observation range is limited to the sea only, SECTOR scanning with a limited azimuth scanning range may be performed. Observing the structure of the fog in the altitude direction is effective for knowing the fog development status in more detail. In this case, PPI scanning or SECTOR scanning may be performed while changing the elevation angle to a plurality of angles.

Observation data (such as a radar image) obtained by the radar device is passed to the fog whistling determination means 2. The fog whistling determination means 2 detects fog distribution from the radar image. If the fog distribution is detected, it is determined that the fog whistle is required, and the fog whistle 3 is blown to notify the ship traveling in the vicinity of the land. Thereby, the safety of the navigation of the ship when the visibility is not sufficient due to the fog can be improved.

As described above, in the present embodiment, the use of the radar apparatus for detecting the fog distribution makes it possible to measure the sea fog over a wide area at a time. As a result, the fog distribution can be detected more reliably.

Embodiment 2 FIG. 3 is a block diagram showing another embodiment of the present invention. In FIG. 3, reference numeral 201 denotes a visibility range distribution calculating means for calculating a visibility distance distribution from observation data obtained by a radar apparatus; 202, a bad visibility area calculating means for obtaining a fog distribution area from the calculated visibility distance distribution;
Is a bad visibility area determining means for determining necessity of fog whistling based on the obtained fog distribution area. The observation of the fog distribution by the radar device 1 and the operation of the fog flute by the fog flute 3 when it is determined that the fog flute is necessary are the same as those described in the first embodiment.

In this embodiment, the necessity of the fog whistling is determined based on the size of the area of the bad visibility area. First,
The visibility distance distribution calculation means 201 calculates the visibility distance distribution from the radar image obtained by the radar device. The data directly obtained by the radar device is the echo intensity of the radio wave reflected from the fog. The reflectivity of the fog is obtained by correcting the distance from the radar device, attenuation by the atmosphere and fog to the echo intensity. Furthermore, the visibility distance can be calculated by using the empirical formula indicating the relationship between the fog reflectance and the amount of mist and the empirical formula indicating the relationship between the amount of mist and the visibility distance.

Next, the area of the bad visibility area having a short visibility distance is obtained by the bad visibility area calculation means 202. First, at each point in the observation region, a predetermined visibility distance threshold value is compared with the visibility distance of the point obtained by the visibility distance distribution calculating means, and the visibility distance is determined to be greater than the visibility distance threshold. The point with the shortest is the bad visibility point. As a result, a bad visibility area is obtained, and the area of the area is obtained.

The bad visibility area determining means 203 compares the bad visibility area with a predetermined fog distribution area threshold value. If the bad visibility area is larger than the fog distribution area threshold value, fog whistling is required. It is determined that there is.

FIG. 4 is a flowchart showing the flow of the above fog flute blowing method. In FIG. 4, fog observation is performed by the radar device in step 1; fog distribution is calculated from observation data in the radar device in step 2; the fog distribution is converted into a visibility distance in step 3; The area of the area below the visibility distance threshold is compared with the fog distribution area threshold. At this time, if the former is larger, step 5
And return to step 1 fog observation. vice versa,
If the former is smaller, the process proceeds to step 6; if the fog flute is sounding, the process proceeds to step 7 to end the fog whistling.
If the fog is not blowing, the process directly returns to the fog observation in step 1.

The visibility distance threshold value used by the visibility distance distribution calculation means 202 and the fog distribution area threshold value used by the bad visibility area determination means 203 are determined empirically according to the geographical conditions of the installation location of the fog whistling device. It should be determined.

As described above, in the present embodiment, the necessity of fog whistling is determined based on the size of the inferior visibility area, so that fog whistling can be performed only in the case of fog that affects ship navigation. It becomes possible.

Embodiment 3 FIG. As the frequency of the radio wave used in the radar device, it is preferable to use a frequency at which the reflection of the radio wave by the fog can be observed and the attenuation of the radio wave by the atmosphere or the fog is small. Specifically, a millimeter wave radio wave such as a Ka band is effective. However, even in the millimeter wave band, when the density of the fog is high, the attenuation of the radio wave due to the fog increases.
In this case, the detection distance of the radar device becomes short.
However, even if the detection distance of the radar device is shortened,
If fog is occurring in a short distance, it may be determined that fog whistling is necessary.

FIG. 5 is a flowchart showing the flow of the fog whistle blowing method on the assumption that the detection distance is shortened. In FIG. 5, in step 101, when fog detection becomes impossible beyond a certain point due to radio wave attenuation, the visibility distance beyond that point is set to 0. Other steps are the same as those in FIG.

Thus, in the distance section where the visibility distance is set to 0, it is determined that the visibility distance is equal to or less than the visibility distance threshold value. If such a determination that fog detection is not possible occurs at a plurality of azimuth angles, it is determined that visibility is deteriorated in an area larger than the fog distribution area threshold value, so that fog whistling is performed. In such a case, it is not possible to know exactly how thick the fog area spreads in the distance direction,
Since it can be considered that dense fog is occurring over a plurality of azimuths, it is considered appropriate to perform fog whistling.

As described above, in the present embodiment, even when the fog detection distance is shortened due to the dense fog, the fog flute can be automatically blown appropriately.

Embodiment 4 As a sensor capable of observing the fog distribution on the sea, there is a passive sensor mounted on a satellite (hereinafter, referred to as a “satellite mounted sensor”) such as an infrared sensor other than the radar device. A satellite-mounted sensor observes the ocean from a long distance in the satellite orbit, so the spatial resolution of the sensor is low.Because it is a passive sensor, it can only see the surface of the fog viewed from the sky. Although inferior, it is superior to radar equipment in that the observation area is wide. Therefore, when the detection distance of the radar device is short, such as when the density of the fog is high, the combined use of the radar device and the satellite-mounted sensor is effective.

FIG. 6 is a block diagram of a fog whistling apparatus using satellite data according to an embodiment of the present invention. In FIG. 6, reference numeral 4 denotes satellite data acquisition means. Other reference numerals are the same as those described in FIG. The fog distribution image obtained by the satellite data acquisition unit is input to the fog whistling determination unit 2 together with the fog distribution radar image obtained by the radar device 1. Regarding the detection distance range of the radar device, the radar image of the fog distribution of the radar device is used because it has advantages such as high spatial resolution of the radar device and observability of the inside of the fog. For a distance longer than the radar device detection distance, a fog distribution image obtained by the radar device is combined with a fog distribution image obtained by a sensor mounted on a satellite.

FIG. 7 is a diagram for explaining a comparison of the observation range between fog observation by the onboard satellite sensor and fog observation by the radar device according to the embodiment of the present invention. As shown in the figure, the radar device can monitor local fog in detail and predict fog fluctuation in a short time, while the satellite can monitor fog over a wide area, Fog fluctuation can be predicted.

As described above, since satellite data is used in the present embodiment, fog can be observed over a wider area than when fog observation is performed by the radar apparatus alone. Further, when fog prediction is performed by monitoring the movement of the fog distribution, fog prediction for a longer time is possible.

Embodiment 5 Monitoring fog at sea can also be done by ship. As a method of monitoring fog on a ship, there are sensors such as a visibility meter and a TV camera, and visual observation by a person. What is observed by the radar device is the intensity of the radio wave reflected by the fog, which corresponds to the characteristic of the reflection of the radio wave by the fog, that is, the radar reflection factor.

The relationship between fog radar reflection factor and visibility varies with the type of fog. Therefore, in order to obtain the visibility distance from the observation result of the radar device, it is necessary to assume the type of fog. The type of fog needs to be determined according to the weather conditions such as the region, season, and temperature at the time of occurrence.If it is possible to measure the fog at the same point simultaneously with a sensor other than the radar device, the radar device based on the type of fog Data calibration can be performed automatically.

FIG. 8 is a block diagram of a fog whistling apparatus utilizing such fog information on a ship. In FIG. 8, 5
Fog information acquisition means for capturing visibility distance data observed by a second observation means different from the radar device (for example, a sensor such as the visibility meter or a TV camera installed on a ship or visual observation by a person); Numeral 6 denotes a visibility distance correction means for calibrating the observation data by comparing the observation data from the radar device with the visibility distance data from the fog information acquisition means. Other reference numerals are the same as those in FIG.

The fog information acquiring means 5 acquires visibility range data obtained by a fog sensor on the ship or visual observation on the ship and positional information of the ship. On the other hand, in radar equipment,
The distribution of the fog radar reflection factor is obtained. The radar reflection factor obtained by the radar device is converted into visibility distance data by assuming the type of fog. However, when the characteristics of the fog such as the particle size distribution are different from those assumed, an error occurs in the conversion into the visibility distance data. Therefore, the error is calibrated by comparing the visibility distance data obtained on the ship with the radar reflection factor of the fog at the ship position obtained by the radar device.

As described above, in the present embodiment, the accuracy of visibility measurement by the radar device can be improved by calibrating the observation data observed by the radar device with the visibility distance data measured on the ship. Thus, it is possible to more accurately determine the fog flute.

[0039]

As described above, according to the first aspect of the present invention, the use of the radar apparatus for detecting the fog distribution makes it possible to measure the sea fog over a wide area at one time. Since fog distribution can be detected more reliably than fog detection at a point position, it is possible to automatically blow a fog whistle.

According to the second aspect of the present invention, it is possible to perform the fog whistling only in the case of fog that affects the navigation of the ship by determining the necessity of the fog whistling.

Further, according to the third aspect of the present invention, it is possible to appropriately perform the automatic blowing of the fog whistle even when the fog detection distance becomes short.

According to the fourth aspect of the present invention, since the observation target is identified, it is possible to more appropriately perform automatic fog whistling even when the fog detection distance becomes short.

According to the fifth aspect of the invention, it is possible to observe the fog over a wide range, and it is possible to predict the fog for a longer time.

According to the sixth aspect of the present invention, the accuracy of the visibility measurement by the radar device can be improved by calibrating the data of the radar device with the visibility measured on the ship. The judgment can be made more accurately.

According to the seventh aspect of the present invention, a fog observation step of performing fog observation at sea by the radar apparatus, a fog distribution calculation step of calculating a fog distribution from radar data obtained in the fog observation step, A visibility distance distribution calculating step of obtaining a visibility distance distribution from the fog distribution obtained in the distribution calculating step, and a visibility distance equal to or less than a threshold of a predetermined visibility distance from the visibility distance distribution obtained in the visibility distance distribution calculating step. A fog whistling sound determining step of determining that fog whistling is necessary when the area of the region is equal to or greater than a predetermined threshold value, and a fog whistling sound step of performing a fog whistling sound at the fog whistling sound determination step The fog flute can be automatically blown.

[Brief description of the drawings]

FIG. 1 is a block diagram of a fog whistling device according to Embodiment 1 of the present invention.

FIG. 2 is an explanatory diagram of an operation concept of the fog whistling device according to the first embodiment of the present invention.

FIG. 3 is a block diagram of a fog whistling device according to a second embodiment of the present invention.

FIG. 4 is a processing flowchart of a fog whistling device according to Embodiment 2 of the present invention.

FIG. 5 is a processing flowchart of a fog whistling device according to Embodiment 3 of the present invention.

FIG. 6 is a block diagram of a fog whistling device according to a fourth embodiment of the present invention.

FIG. 7 is a diagram illustrating a comparison between fog observation by a satellite-mounted sensor and fog observation by a radar device according to a fourth embodiment of the present invention.

FIG. 8 is a block diagram of a fog whistling device according to Embodiment 5 of the present invention.

[Explanation of symbols]

1 radar device, 2 fog whistling judgment means, 3 fog flute, 4
Satellite data acquisition means, 5 fog information acquisition means, 6 visibility range correction means, 201 visibility range distribution calculation means, 202
Bad visibility area calculation means, 203 Bad visibility area determination means.

Claims (7)

[Claims] 1. A fog whistling device for notifying the occurrence of fog in a monitoring area by blowing a fog whistle, comprising: a radar device for observing the distribution of fog generated in the monitoring region; A fog whistling device comprising: a fog whistling sound determining means for determining; and a fog whistle sounding based on a result of the determination by the fog flute sounding determining means. 2. A fog whistling determination means, a visibility distance distribution calculating means for calculating a visibility distance distribution from observation data of a radar device, and a visibility distance threshold in which a visibility distance is set in the calculated visibility distance distribution. Means for calculating a fog distribution area of a region equal to or less than a value, and a bad visibility which determines that fog whistling is necessary when the obtained fog distribution area is equal to or greater than a predetermined fog distribution area threshold value. 2. The method according to claim 1, further comprising an area determining means.
The fog flute sounding device according to the above. 3. The visibility distance distribution calculating means sets a visibility distance of an observation azimuth beyond a point where observation by a radar device becomes impossible in a certain observation azimuth within a monitoring area, to 0. The fog sounding device according to claim 2. 4. A visibility distance distribution calculating means for identifying an observation target based on observation data observed by the radar device, and, when the observation target is identified as fog, a point where observation becomes impossible. 4. The fog whistling apparatus according to claim 3, wherein the visibility distance of the further observation direction is set to 0. 5. A fog whistling device for notifying the occurrence of fog in a monitoring area by a fog flute sounding, a radar apparatus for observing the distribution of fog generated in the monitoring area, and observation data of the fog distribution observed by a satellite. A fog whistle sound determining means for determining whether or not a fog whistle sound is necessary according to observation data obtained from the radar device and the satellite data obtaining means, respectively, and a sound based on a result of the determination by the fog sound sound determination means. A fog flute sounding device comprising: 6. A fog whistling device for notifying the occurrence of fog in a monitoring area by a fog flute sounding, comprising: a radar device for observing the distribution of fog generated in the monitoring region; Fog information acquisition means for capturing visibility distance data observed by different second observation means; and calibration of the observation data by comparing observation data from the radar device with visibility distance data from the fog information acquisition means. A fog whistle sounding means for judging the necessity of fog flute sounding according to the calibrated observation data, and a fog whistle sounding based on the judgment result of the fog sound sounding judgment means. And fog whistling device. 7. A fog observation step of observing a fog distribution by a radar device, a fog distribution calculation step of calculating a fog distribution from observation data obtained in the fog observation step, and a fog distribution obtained in the fog distribution calculation step From the visibility distance distribution obtained in the visibility distance distribution calculating step, an area of a region having a visibility distance equal to or less than a preset visibility distance threshold is set in advance. A fog whistling sound is determined to be necessary if the fog distribution area is greater than or equal to the threshold value, and a fog whistling sound step for performing fog flute sounding based on the determination result in the fog whistling sound determination step. And the fog flute method.