JPH08304547A - Equipment and system for search by laser radar - Google Patents

Abstract

PURPOSE: To obtain an equipment and a system for search which enable quick discovery of a victim or the like without relying on a visual search. CONSTITUTION: A reflecting sheet R reflecting a laser beam is provided on a life jacket P of a victim M. A search equipment mounted on a search plane S transmits the laser beam, while making it scan, receives a reflected laser light of the laser beam reflected by the reflecting sheet and detects a distance to the victim on the basis of a time difference between the transmission of the laser beam and the reception of the reflected laser light. The position of the victim is detected from the direction of scanning, the altitude and bearing of the search plane and others at that time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for searching a distressed ship or aircraft and a victim, and more particularly to a laser radar-based search device and search system effective for searching at sea.

[0002]

2. Description of the Related Art Due to the development of communication technology in recent years, when a ship, an airplane, etc. is in distress, the distress is informed by radio communication, and the position of the distress is notified by radio to facilitate the search. It becomes possible. However, when the radio is damaged, such a method cannot be used, and the search is mainly carried out by aircraft from the air, particularly by a helicopter, and the ship visually distressed by the passengers of the search machine. Or to search for an aircraft. In this case, although a search using a radio wave as a medium is also performed, this radar method is effective for a search for an object such as a ship or an aircraft that easily reflects the radio wave. Searching for a distressed individual with few reflections is extremely difficult.

[0003]

For this reason, when searching for a human, as described above, it is inevitable to rely solely on the visual inspection of the passenger of the searcher to find the victim. However, it is difficult to find a human being, which is a small object, when the altitude of the search machine is high. Further, when the altitude of the search machine is lowered, the search range becomes narrower, and it takes time to find the problem. Furthermore, at night, a search is performed while illuminating a searchlight, but it is difficult to search a wide range because the illumination range of this searchlight is limited.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a search device and a search system capable of quickly finding a victim or the like.

[0005]

Means for Solving the Problems A search device of the present invention comprises means for generating a laser beam and transmitting light to a distressed object, means for receiving laser light reflected from the distressed object, and the light transmitting means. Means for simultaneously scanning the optical axis direction of the means and the light receiving means, and means for detecting the position of the distressed object by calculating the distance to the distressed object based on the time difference between when the laser beam is transmitted and when the laser beam is received. Equipped with.

In this case, the means for detecting the position of the distressed object is the scanning direction of the laser beam when the laser beam is received,
It is preferable to detect the relative position of the distress target with respect to the search device based on information such as the altitude of the search device and the direction of the search device. It is also preferable that the search device is provided with an absolute position detection device using GPS satellites, and the absolute position of the distress target is detected based on this absolute position information.

Further, in the search system of the present invention, a reflecting material for reflecting the laser beam is installed on the distressed object, and the searching device sends the laser beam while scanning and reflects the laser beam. The reflected laser light of the generated laser beam is received, and the distance to the distress target is detected based on the time difference between the sending of the laser beam and the reception of the reflected laser light. In this case, it is preferable that the reflecting material is provided on a life preserver or the like worn by the victim and has a high reflectance with respect to the laser beam.

[0008]

According to the present invention, a laser beam can be used to find a victim, and the distance and position to the victim can be detected. Therefore, the victim can be found quickly. Becomes An apparatus for performing a search activity using a laser radar is disclosed in Japanese Patent Laid-Open No. 52276/1990, but the technique described in this publication does not directly detect a victim by using the laser radar. . In addition, although various techniques for performing distance measurement using a laser beam have been proposed,
Nothing has been used to find an object while scanning a laser beam.

[0009]

Next, the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of a search device used in the search system of the present invention. In the figure, the search device is an exterior part 1 installed outside a search machine such as a helicopter.
And an internal part 2 provided inside. The exterior part 1 includes a laser beam generator 11 that generates a laser beam, a light transmitter 12 that focuses the laser beam and emits it as a laser beam having a required beam diameter, and a reflected beam of the transmitted laser beam. A light receiving unit 13 that receives light and a scanner unit 14 that integrally scans the light transmitting unit 12 and the light receiving unit 13 are provided. The exterior part 1 is incorporated in a spherical housing 32 suspended by a stem 31 on the lower surface of the searcher as shown in FIG. 2, for example, and is elongated in one direction of the housing 32. The laser light generator 11, the light transmitter 12, the light receiver 13, and the scanner 14 are provided in the window 33 provided.
Has been arranged. The laser beam can be transmitted and received, and scanning can be performed by remote operation from the cockpit.

Here, the scanner unit 14 is constructed by using, for example, a polygon mirror 34, and by rotating the polygon mirror 34 at a high speed, a predetermined range in a direction perpendicular to the traveling direction of the search machine is obtained. It is configured to move a laser beam inside to perform scanning. That is,
As shown in FIG. 2, the optical axes of the light transmitting unit 12 and the light receiving unit 13 are coaxially positioned via a semi-transmissive mirror 35, and the polygon mirror 34 is arranged on this optical axis. This allows
As the polygon mirror 34 rotates, the laser beam from the light transmitting unit 12 is scanned in the rotation direction of the polygon mirror 34,
At the same time, the light receiving unit 13 is configured to receive the light reflected from the victim or the like. With this, as the searcher advances, it becomes possible to irradiate a band-shaped range of a predetermined width along the traveling direction of the laser beam and receive laser light reflected in the band-shaped range. . In addition,
When the laser beam is scanned at a low speed, each part may be driven so that each optical axis of the light traveling part and the light receiving part can be horizontally swung.

On the other hand, the inner part 2 has a control / calculation part 21.
Is provided. The control / arithmetic unit 21 controls the electric power supplied to the laser light generator 11, and the light transmitter 12
The position of the victim is calculated based on the light reception signal from the light receiving unit 13 while controlling the light transmission operation of the laser beam and the scanning by the scanner unit 14. That is, the control / calculation unit 21
Is provided in the search machine, the received light signal of the laser beam received by the light receiving section 13, the angle signal output from the scanner section 14, the altitude signal from the altimeter 22 provided in the search machine, and the search signal. The azimuth signal from the azimuth meter 23 is input, and the position of the victim is calculated based on the information included in these signals. Then, the position of the victim who is obtained as a result of the calculation is displayed on the display unit 24.

The figure shows the operating state of searching for a victim by a searcher equipped with a search device having such a configuration. In ships and aircraft, a reflective sheet or other reflective material that reflects laser light is installed or attached in advance on a part of the hull or body.
Also, those who board these ships and aircraft should attach a similar reflection sheet or the like to a part of the life preserver or the like to be worn. In this case, for example, in the case of distress on the sea, it is preferable to install the reflective sheet or the reflective material in a place where the reflective sheet or the reflective material appears above the sea surface.

Therefore, in the example of FIG. 3, the victim M who is drifting on the sea wears the life jacket P, and the reflection sheet R is attached to a part of the life jacket P. Then, the searcher S advances while scanning the laser beam emitted from the light traveling unit 12 with respect to the sea surface by the scanner unit 14, and when the victim M exists in the belt-shaped range, the laser beam is reflected. The sheet R is irradiated and the reflected laser light is immediately received by the light receiving unit 12.
At this time, the beam diameter of the laser beam is extremely small compared to the beam diameter of ordinary search lamps, etc., and because it has excellent straightness, it receives reflected light from the sea surface irradiated by the laser beam and other floating objects. Since the probability that the portion 12 can receive light with high brightness is extremely small, it is relatively easy to distinguish it from the reflected light from the reflecting sheet R of the victim.

Therefore, when the light receiving unit 12 detects the laser beam, the control / calculation unit 21 can calculate the distance to the victim M from the time difference between the light transmission and the light reception at that time. At the same time, the calculation is performed based on the laser beam scanning angle θ in the scanner unit 14 at that time, the altitude H of the aircraft, and the traveling azimuth X. This operation is
For example, trigonometry as shown in FIG. 4 is performed, and by this, it is possible to determine in which azimuth and at which distance the distressed person M exists with respect to the own device S. By displaying this on the display unit 24, the searcher who is on the search machine S can recognize the position of the distressed person M and can quickly perform distressed activities.

Here, depending on the posture of the victim when drifting over the sea, the probability that the reflecting sheet faces the optical axis direction of the laser beam is small, and it is difficult to receive the laser beam reflected by the reflecting sheet. Sometimes. In order to avoid this, a plurality of pairs of the light transmitting unit 12 and the light receiving unit 13 shown in FIG. 2 are provided, and the plurality of laser beams are scanned by the scanner unit 14 at different timings, so that one of the laser beams The reflected light can be received by the light receiving section, and the probability of receiving light can be increased.

Further, by forming a diffusion film on the reflection sheet R to slightly diffuse the irradiated laser light, it is possible to increase the reflection angle of the laser beam and increase the probability of light reception at the light receiving portion. Becomes Furthermore, by setting the reflection sheet R so that the reflectance of the laser beam with respect to the wavelength light is significantly higher than that with the other wavelength light, the reflection sheet R can be easily distinguished from the reflection of the laser beam on another object. It is also possible.

Further, in the above embodiment, the position of the victim is determined as a relative position to the searcher. For example, the searcher is provided with its own position detecting device using GPS satellites. At the same time as detecting the relative position of the victim to the aircraft, it is also possible to obtain the absolute position of the victim by performing calculation based on the absolute position of the aircraft itself.

[0018]

As described above, the search device of the present invention is a means for generating and transmitting a laser beam, a means for receiving laser light reflected from a distressed object, a light transmitting means and a light receiving means. Scanning means for simultaneously scanning the optical axis direction of,
It is equipped with a means for calculating the distance to the distressed object by calculating the distance to the distressed object based on the time difference between when the laser beam is sent and when it is received, or because it is equipped with a means for detecting the position of the distressed object. It is possible to detect a victim or the like by using the laser beam without relying on the laser beam, and to detect the distance or position to the victim or the like, and it is possible to quickly find the victim or the like.

Further, the relative position of the distress target with respect to the search device is detected based on information such as the scanning direction of the laser beam when the laser beam is received, the altitude of the search device, the direction of the search device, or the use of a GPS satellite. By detecting the absolute position of the distress target based on the detected absolute position, it becomes possible to find the distress target more quickly.

On the other hand, in the search system of the present invention, the object to be distressed is provided with a reflecting material for reflecting the laser beam. In the searching device, the laser beam is transmitted while being scanned and reflected by the reflecting material. By receiving the reflected laser light of the laser beam, the distance to the distress target based on the time difference between the sending of these laser beams and the reception of the reflected laser light, and by detecting the position of the distress target, It is possible to easily distinguish the reflected light from other objects, and it is possible to quickly find the distressed object without causing misidentification.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of a search device of the present invention.

FIG. 2 is a schematic diagram showing a schematic configuration of an exterior part of the search device.

FIG. 3 is a diagram for explaining a search operation state.

FIG. 4 is a diagram for explaining the principle of calculating the position of a victim.

[Explanation of symbols]

 1 Outer Structure Part 2 Inner Structure Part 11 Laser Light Generation Part 12 Light Transmitting Part 13 Light Receiving Part 14 Scanner Part 21 Control / Calculation Part 22 Altimeter 23 Compass Meter 24 Display Part S Searcher M Reflector R Reflective Sheet

Claims (5)

[Claims] 1. A means for generating a laser beam and sending the light to a distressed object, a means for receiving the laser light reflected from the distressed object, and a scanning means for simultaneously scanning the optical axis directions of the light sending means and the light receiving means. Searching by a laser radar, characterized by comprising: a scanning means and a means for detecting the position of the distressed object by calculating the distance to the distressed object based on the time difference between when the laser beam is transmitted and when the laser beam is received. apparatus. 2. The means for detecting the position of the distressed object is the relative position of the distressed object with respect to the search device based on information such as the scanning direction of the laser beam when the laser beam is received, the altitude of the search device, and the direction of the search device. The laser radar search device according to claim 1, which detects a position. 3. The laser radar search device according to claim 2, wherein the search device is provided with an absolute position detection device using a GPS satellite, and detects the absolute position of the distress target based on the information of the absolute position. 4. A reflecting material for reflecting the laser beam is installed on the distressed object, and the search device transmits the laser beam while scanning and reflects the laser beam reflected by the reflecting material. A search system using a laser radar, which receives a laser beam and detects a distance to a distress target based on a time difference between the transmission of the laser beam and the reception of the reflected laser beam. 5. The laser radar search system according to claim 4, wherein the reflector is provided on a life preserver or the like worn by a victim and has a high reflectance with respect to the laser beam.