JP2005212553A - Detecting device and detecting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a detecting device and a detecting method simplifying a system and reducing equipment cost. <P>SOLUTION: The detecting device has laser radar 10 scanning a prescribed region and a circumferential region adjacent to the prescribed region; a radar information creating means 21 for creating three-dimensional radar information from distance information detected by the laser radar 10 and scanning direction information; an object detecting means 22 for detecting an object existing in the prescribed region and the circumferential region from the three-dimensional radar information; a region recognizing means 23 for recognizing the prescribed region and the circumferential region; and a train identifying means 24 for identifying whether the object is a train or not. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a detection device and a detection method for detecting an object passing through a predetermined area, for example, a level crossing, and in particular, whether the detected object is a train based on a reflected wave of a signal transmitted from a laser radar. The present invention relates to a detection device and a detection method for detecting whether or not.

As a conventional detection device, an optical method, a loop coil method, a camera image processing method, and an underwater scanning laser method are known.
An optical detection device has a projector and a light receiver arranged across a railroad crossing, and detects an obstacle when an object is shielded from light.
The loop coil type detection device uses a phenomenon in which an electromagnetic induction coil is laid in the railroad crossing and the impedance of the coil changes depending on the presence or absence of a metal body near the electromagnetic induction coil, thereby changing the resonance frequency. It is detected as an obstacle.
The camera image processing type detection device is provided with a camera for photographing a railroad crossing and detects an obstacle by processing an image photographed using the camera.
In the underwater scanning laser system, a laser beam is scanned horizontally, and an obstacle is detected by measuring the distance from reflected light from an object.
In such an optical method, loop coil method, camera image processing method, underwater scanning laser method detection device, for example, the state in which it is determined that there is an obstacle as described above has continued for, for example, 6 seconds or more. In this case, it is set so that the detection device does not operate more than necessary by transmitting a stop signal from the special signal light emitter to the train as “there is an obstacle”.

In the optical detection device, the optical axis between the projector and the light receiver is linear, and in the loop coil detection device, the electromagnetic induction coil is partially installed. Obstacles cannot be detected. For example, the optical detection device detects everything that blocks the thin optical axis as an obstacle, and the loop coil detection device detects all the metal on the loop coil that changes the oscillation frequency to a predetermined value or more. It will be detected as an obstacle. Further, an object in a crossing at a position where the optical axis of the optical detection device is not shielded, or an object such as a non-metal that cannot be detected by the loop coil detection device cannot be detected as an obstacle. In other words, because the size, shape, position, etc. of the object in the crossing cannot be determined, people working at the crossing or construction buckets may be erroneously detected as obstacles, and vice versa. In addition, a true obstacle may not be detected. Therefore, if obstacles are detected without omission throughout the railroad crossing, it is necessary to install a large number of light emitters / receivers and electromagnetic induction coils, resulting in an increase in the installation cost and construction cost of the apparatus. Furthermore, in the conventional detection device described above, piping and wiring work for connecting a plurality of light emitters / receivers and a plurality of loop coils, in particular, it costs a lot of money to carry out such work through roads and tracks. There is a problem.
In addition, the camera image processing type detection device can detect obstacles in the entire level crossing, but it is difficult to detect obstacles because the visibility is significantly reduced at night or in bad weather. Become. That is, there is a problem that a camera image processing type detection device is easily affected by the surrounding environment and cannot always maintain sufficient performance.
Further, in the horizontal scanning laser type detection device, since the installation height is fixed, in order to detect a lying pedestrian or the like, the installation height must be lowered to about 10 cm. In this case, it becomes difficult to apply at level crossings with large irregularities.

Therefore, in order to solve these problems, a signal propagating in the air, for example, a laser is emitted to the object in the crossing, and the object information is collected by collecting the azimuth information and distance information of the object based on the reflected signal. Has been proposed (see Patent Document 1).
In addition to the detection device that two-dimensionally emits a laser to detect an object in the crossing, as in the detection device described in Patent Document 1, 1 or so that the laser can be emitted to a predetermined region in the crossing. There has also been proposed a detection device in which a plurality of laser radars are arranged at a predetermined height and a laser is emitted from the laser radars to detect an object in a railroad crossing.
Japanese Unexamined Patent Publication No. 2003-11824 (page 2-3, FIG. 1)

  In the conventional detection device, in order to determine whether the object detected in the crossing is an obstacle, for the train passing through the crossing, so as not to erroneously determine the train as an obstacle. A train detection sensor is installed outside the railroad crossing, and the train and the obstacle are distinguished by detecting the train with the train detection sensor. However, when such a train detection sensor is installed, the system having the train detection sensor becomes complicated and the equipment cost required for the system becomes enormous. Further, it is difficult for a railroad crossing installed in a limited space to secure a place for installing such a train detection sensor. Therefore, simplification of the system including the detection device and reduction of equipment costs are desired.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a detection device and a detection method in which the system is simplified and the equipment cost is reduced.

  The present invention employs the following means in order to solve the above problems. That is, the detection apparatus according to the present invention provides a three-dimensional radar information from a laser radar that scans a predetermined region and a peripheral region adjacent to the predetermined region, distance information detected by the laser radar, and information on the scanning direction. Radar information generating means for obtaining the object, object detection means for detecting an object existing in the predetermined area and the peripheral area from the three-dimensional radar information, and area recognition means for recognizing the predetermined area and the peripheral area; And train identification means for identifying whether or not the object is a train when the object enters the peripheral area.

  In the detection device according to the present invention, the predetermined area is a railroad crossing, and the peripheral area is adjacent to the predetermined area in an extending direction of a line laid so as to pass through the predetermined area. It is characterized by.

  According to the present invention, the predetermined region and the peripheral region are scanned with the laser radar, and when the object enters the peripheral region, in order to identify whether the object is a train by the train identification means, the peripheral region is It is possible to detect an object in the surrounding area using only one laser radar without separately installing a detection sensor for detecting the passing object.

  Further, the present invention scans a predetermined region and a peripheral region adjacent to the predetermined region, obtains three-dimensional radar information from distance information detected by the laser radar and information on the scanning direction, and A detection method for detecting an object existing in the predetermined area and the peripheral area from radar information, wherein the object is recognized when the predetermined area and the peripheral area are recognized and the object enters the peripheral area. It is characterized by identifying whether or not is a train.

  According to the present invention, when a predetermined area and a surrounding area are scanned and an object enters the surrounding area, detection is performed to detect an object passing through the surrounding area in order to identify whether the object is a train. It is possible to detect an object with respect to the peripheral region using only one laser radar without separately installing a sensor.

  According to the detection device of the present invention, it is possible to detect whether or not an object is a train by detecting an object in the surrounding area using only one laser radar without installing a plurality of laser radars. Therefore, the system can be simplified and the equipment cost can be reduced.

  Further, according to the detection method of the present invention, an object is detected with respect to the peripheral region using only one laser radar without installing a plurality of laser radars, and whether or not the object is a train is identified. This makes it possible to simplify the system and reduce equipment costs.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing a schematic configuration of a detection apparatus to which the present invention is applied.
The laser radar 10 is housed integrally in a predetermined housing to constitute a sensor unit, and is installed at a predetermined height such as a wall surface of a building or a utility pole. For example, as shown in FIG. Are arranged to be. The laser radar 10 is provided, for example, with a main scanning motor 12 that rotates the polyhedral mirror 11 at a constant speed, and a rotation axis of the polyhedral mirror 11 that is predetermined with respect to the main scanning motor 12. A sub-scanning motor 13 that swings the rotating surface of the polyhedral mirror 11 at a predetermined speed by being tilted within an angle range is provided. By irradiating the polyhedral mirror 11 with the laser pulse light emitted from the laser light source 14 via the half mirror 15, the laser pulse light is irradiated to a predetermined region according to the rotation and the inclination of the polyhedral mirror 11, and Reflected light from a predetermined region of the laser pulse light is received and detected by the light receiver 17 from the polyhedral mirror 11 through the condenser lens 16.

  That is, the laser radar 10 deflects and scans the irradiation direction of the laser pulse light in the main scanning direction (x direction) at a high speed by rotating and swinging the polyhedral mirror 11, while scanning the scanning surface in the sub scanning direction (y Direction), thereby scanning the entire predetermined area as illustrated in FIG. Then, the reflected light from various objects existing in a predetermined area is received in synchronization with the irradiation of the laser pulse light, and the object from the light reception timing (the elapsed time from the laser pulse light irradiation timing to the reflected light reception timing) The distance information to (reflection point) is obtained. The scanning range by the laser radar 10 is set, for example, as 60 degrees in the main scanning (horizontal) direction and 30 degrees in the sub-scanning (vertical) direction. Further, the laser radar 10 is configured to sequentially detect information of reflected light by irradiating laser pulse light every time the scanning direction changes by 0.1 degree and receiving the reflected light, for example.

  On the other hand, the detection device main body 20 including, for example, a personal computer includes radar information creation means 21 for obtaining three-dimensional radar information indicating the spatial coordinates of the reflection point from the reflected light information detected using the laser radar 10 described above. ing. Specifically, the radar information creating means 21 receives the synchronization signal from the laser pulse scanning circuit 21a that drives the laser light source 14, for example, as shown in FIG. A reflected light detection unit 21b for measuring, a distance information conversion unit 21c for converting the measurement time into distance information, and a density conversion unit 21d for converting the distance information into density information are provided.

  It is also possible to directly convert the measurement time into shading information. In this embodiment, the distance information is shown as an example in which the distance information is converted into light and shade information that becomes darker as the distance increases. However, tone conversion in which the color changes stepwise according to the distance may be performed. Further, when it is not necessary to visualize the three-dimensional radar information as a laser radar image, the measurement time obtained by the reflected light detection unit 21b is directly used as the information on the reflection point of the laser pulse light without performing the above-described density conversion or the like. Can also be used.

  The laser radar image as the three-dimensional radar information has a predetermined image memory 21e according to the information on the main scanning angle and the sub-scanning angle obtained from the laser pulse scanning circuit 21a based on the density information (distance information) obtained as described above. Created by mapping sequentially. That is, the density information (distance information) obtained at that time is written in the coordinates (address of the image memory 21e) specified by the main scanning angle and the sub-scanning angle indicating the scanning direction of the laser pulse light. A laser radar image for three-dimensionally specifying the reflection point of the laser pulse light on the above-mentioned predetermined region is created on 21e.

  In addition to the radar information creation means 21 described above, the detection device main body 20 detects an object present in a predetermined region and a peripheral region adjacent to the predetermined region from three-dimensional radar information (laser radar image). Means 22; area recognition means 23 for recognizing a predetermined area and a peripheral area; and a train identification means 24 for identifying whether or not the object is a train when the object enters the peripheral area. . Further, in addition to these basic processing functions, the detection device main body 20 includes a spatial coordinate conversion means 25, a motion detection means 26, and an auxiliary information display means 27 as will be described later.

  Explaining these functions, the object detection means 22 basically recognizes a group of a predetermined number or more of reflection points whose spatial coordinates are continuous from 3D radar information as one object having a certain size, A function of detecting the center of gravity as an object position is provided. Then, the motion detection means 26 determines whether the object is a fixed object or a moving object from the temporal change in the position of the center of gravity of the object detected in this way. In particular, when the object is recognized as a moving object, the direction of change in the center of gravity position is recognized as the movement direction, and the amount of change in the center of gravity position is recognized as the movement speed.

The spatial coordinate conversion means 25 is for simplifying the shape of the object based on the three-dimensional radar information from the radar information creation means 21 and converting it into spatial coordinates. This simplified image is displayed on a monitor 30 connected to the detection apparatus main body 20.
Further, the auxiliary information display means 27 displays a frame-shaped identification mark (auxiliary information) surrounding the recognized object as described above so as to overlap the image displayed on the monitor 30, thereby highlighting the object. It enhances discrimination.

  Note that the image displayed on the monitor 30 at this time is appropriately recorded using the image recording device 31 connected to the detection device main body 20. In particular, when an abnormal entry of an object into a predetermined area is detected by the object detection described above, the object that has entered the predetermined area is recorded by recording it in the image recording device 31 together with the laser radar image described above. You may make it use for.

FIG. 4 is a plan view of a railroad crossing using the above-described detection device. In FIG. 4, a railroad crossing 41 is shown as a predetermined region, and a vehicle 43 is shown as an object. Further, peripheral regions 41 a and 41 b are respectively provided adjacent to both sides in the extension direction of the track 40 laid so as to pass through the railroad crossing 41 with respect to the railroad crossing 41.
The level crossing 41 is installed across the track 40, and the breakers 42 are installed on both sides of the entrance of the level crossing 41, respectively. In addition, the vehicle 43 passes through the railroad crossing 41 in a direction crossing the track 40. A pedestrian, a bicycle, or the like crosses the railroad crossing 41 as in the case of the vehicle 43, but here, in order to simplify the description, it is assumed that the vehicle 43 is the only object that crosses the railroad crossing 41.

Here, as shown in FIG. 5, the level crossing 41 and the peripheral areas 41 a and 41 b are recognized by the area recognition means 23.
The laser radar 10 is installed outside the railroad crossing 41 and the peripheral areas 41a and 41b and at a predetermined height, that is, at a position where the entire railroad crossing 41 and the peripheral areas 41a and 41b can be detected. The laser radar 10 can irradiate laser pulse light to a peripheral region including the railroad crossing 41 and surrounding the railroad crossing 41 so that the railroad crossing 41 and the entire peripheral regions 41a and 41b can be detected.

Next, a detection method for detecting the vehicle 43 or the train 44 in the railroad crossing 41 and the surrounding areas 41a and 41b using the detection device having the above configuration will be described with reference to the flowchart shown in FIG.
First, the level crossing 41 and the surrounding areas 41a and 41b are scanned using the laser radar 10, and the measurement data higher than the ground in the level crossing 41 and the surrounding areas 41a and 41b using the radar information creation means 21 and the object detection means 22, that is, Then, when the ground is the xy plane, the data protruding in the z direction is selected and the measurement data group is recognized (step S101), and detected as an obstacle from the measurement data group (step S102). Then, it is determined whether or not the detected object is present on the left side outside the railroad crossing 41, that is, in the peripheral area 41a (step S103).

When the detected object is present in the peripheral area 41a (“Yes” in step S103), the train identification means 24 is used to identify whether the object existing in the peripheral area 41a is the vehicle 43 or the train 44. External left side identification processing is performed (step S104), and the flow ends. The flow of the crossing exterior left side identification process will be specifically described later with reference to FIG.
On the other hand, if the detected object does not exist in the peripheral area 41a (“No” in step S103), it is determined whether or not the detected object exists in the right side outside the level crossing 41, that is, in the peripheral area 41b (step S105).

When the detected object is present in the peripheral area 41b (“Yes” in step S105), the train identification means 24 is used to identify whether the object existing in the peripheral area 41b is the vehicle 43 or the train 44. External left side identification processing is performed (step S106). The flow of the crossing exterior left side identification process will be specifically described later with reference to FIG.
On the other hand, when the detected object does not exist in the peripheral area 41b (“No” in step S105), the internal crossing identification for identifying whether the object existing in the crossing 41 is the vehicle 43 using the train identification unit 24. Processing is performed (step S107), and the flow ends. The flow of the crossing internal identification process will be specifically described later with reference to FIG.

  When the flow is finished, it is identified whether the object existing in the railroad crossing 41 and the surrounding areas 41a and 41b is an obstacle vehicle 43 or a train 44. If the object is an obstacle, For example, it is possible to perform a dangerous state detection process such as notifying the train 44 approaching the level crossing 41 that there is an obstacle in the level crossing 41 and in the surrounding areas 41a and 41b.

Here, the specific flow of the crossing exterior left side identification processing in step S104 will be described with reference to the flowchart shown in FIG.
In the crossing exterior left side identification processing in step S104, it is determined whether or not the object present in the peripheral area 41a obtained as a detection result by the object detection means 22 is larger than a predetermined size (step S201). At this time, a value indicating a predetermined size of a preset object, for example, W is set, and on the other hand, the size of the object detected by the object detection unit 22 is digitized, and these values are compared. To judge.

Since this W is set assuming the size of the train 44, when the numerical value of the size of the object is larger than W, that is, it is determined that the object existing in the peripheral area 41a is larger than the predetermined size. If it is determined (“Yes” in step S201), it is determined that the object existing in the peripheral area 41a is a train (step S202).
When the numerical value of the size of the object existing in the peripheral area 41a is smaller than W, that is, when it is determined that the object existing in the peripheral area 41a is smaller than the predetermined size ("No" in step S201), the same object determination is performed. This is performed (step S203).

  Here, the same object determination will be described. The entire detection range of the laser radar 10 is measured once to obtain one frame, and a detection result having information such as the position, size, ID number, and detection time of the object is obtained from the measurement result of this one frame. This is the first detection result. Similarly, the entire detection range of the laser radar 10 is measured once again to make one frame, and a detection result is obtained from the measurement result. This is the second detection result. After that, the first detection result and the second detection result are compared. For example, when the respective coordinates match or approximate, they are recognized as the same object, take over the ID number, and have their center of gravity positions. The moving direction and the moving speed are calculated from the difference between the two and the time difference.

  When the same object is determined in this way and the first detection result and the second detection result are compared for the object detected in the peripheral area 41a, the respective coordinates match or approximate (step S204). In "Yes"), it is determined whether or not the moving direction of the object is different from the traveling direction of the train 44, that is, the extending direction of the track 40 (step S205). When the moving direction of the object is different from the traveling direction of the train 44 (“Yes” in step S205), the object is recognized as an obstacle (step S206).

In addition, for the object detected in the peripheral region 41a, the first detection result and the second detection result are compared, and the respective coordinates do not match or approximate (“No” in step S204), or If the moving direction of the object is the traveling direction of the train 44 (“No” in step S205), the object is not an obstacle and is therefore regarded as a train (step S207).
In step S207, in order to increase the accuracy of identifying the object, an additional process is added to connect to the ON / OFF signal of the level crossing 41 and to determine that the object corresponds to an obstacle when the level crossing 41 is OFF. It is also possible to do.

  Further, the specific flow of the crossing exterior right side identification processing in step S106 is shown in the flowchart of FIG. 8, and steps S301 to S307 in this flowchart are the same as steps S201 to S207 shown in the flowchart of FIG. Therefore, the description is omitted.

A specific flow of the crossing internal identification process in step S107 will be described with reference to the flowchart shown in FIG.
In the internal crossing identification process in step S107, it is determined whether or not an object existing in the peripheral area 41a obtained as a detection result by the object detection means 22 is smaller than a predetermined size (step S401). At this time, a value indicating a predetermined size of a preset object, for example, W is set, and on the other hand, the size of the object detected by the object detection unit 22 is digitized, and these values are compared. Judgment.

Since this W is set assuming the size of the obstacle, for example, the vehicle 43, when the numerical value of the size of the object is smaller than W, that is, the object existing in the peripheral area 41a is larger than the predetermined size. Is determined to be smaller (“Yes” in step S401), it is determined that the object present in the peripheral area 41a is a train (step S402).
When the numerical value of the size of the object existing in the peripheral area 41a is larger than W, that is, when it is determined that the object existing in the peripheral area 41a is larger than the predetermined size ("No" in step S401), the same object determination is performed. This is performed (step S403). In addition, since it is the same as that of said step S203 about the same object determination, description is abbreviate | omitted.

When the same object determination is performed and the first detection result and the second detection result are compared for the object detected in the peripheral region 41a, and the respective coordinates match or approximate (“Yes” in step S404) "), It is recognized as an object obtained from the first detection result (step S405).
In addition, when the first detection result and the second detection result are compared with each other for the object detected in the peripheral region 41a and the respective coordinates do not match or approximate (“No” in step S404), the object Is an obstacle (step S406).

  In such a detection device and a detection method using this detection device, when the railroad crossing 41 and the peripheral regions 41a and 41b are scanned by the laser radar 10, and the object enters the peripheral regions 41a and 41b, the object is a train. In order to identify whether or not there is a train by the train identification means 24, the peripheral regions 41a and 41b are used by using only one laser radar 10 without separately installing a detection sensor for detecting an object passing through the peripheral regions 41a and 41b. It becomes possible to detect an object with respect to.

The present invention is not limited to the railroad crossing 41 as in the above embodiment. For example, a detection device and a detection device are set so that a predetermined region and a peripheral region are set at a track repair work site and its peripheral region, and workers and work vehicles are detected to determine whether they are an obstacle or a train. By applying the method, the same effects as those of the above embodiment can be obtained.
Further, in the above embodiment, when the detection device is linked with the train control system and it is determined that there is an obstacle in the level crossing 41 and the surrounding areas 41a and 41b and the dangerous state detection process is performed, the train 44 is stopped. It is also possible to set to perform control.

  In the above embodiment, in order to improve the identification accuracy when identifying whether the object existing in the railroad crossing 41 and the surrounding areas 41a and 41b is the vehicle 43 or the train 44 as an obstacle, for example, A case where the circuit breaker 42 is raised and a case where it is lowered may be divided, and weighting may be added to the identification determination. That is, for example, when the breaker 42 is raised, an object existing in the railroad crossing 41 and the surrounding areas 41a and 41b is set so that it can be easily determined as the train 44, and when the breaker 42 is lowered, that object is set. May be set so that it can be easily determined that the vehicle 43 is an obstacle.

It is a schematic block diagram of a detection apparatus. It is a figure which shows the scanning form of the detection area by a laser radar. It is a block diagram which shows the rough creation processing means of a laser radar image. It is a schematic plan view of a railroad crossing detected by a detection device and a surrounding area. It is a schematic plan view of a railroad crossing detected by a detection device and a surrounding area. It is a flowchart which shows the detection method in this Embodiment. It is a flowchart which shows the detection method in this Embodiment. It is a flowchart which shows the detection method in this Embodiment. It is a flowchart which shows the detection method in this Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Laser radar 20 Detection apparatus main body 21 Laser information preparation means 22 Object detection means 23 Area recognition means 24 Train identification means 40 Track 41 Railroad crossing 43 Vehicle

Claims (3)

A laser radar that scans a predetermined region and a peripheral region adjacent to the predetermined region;
Radar information creating means for obtaining three-dimensional radar information from distance information detected by the laser radar and information on its scanning direction;
An object detection means for detecting an object existing in the predetermined area and the peripheral area from the three-dimensional radar information;
Area recognition means for recognizing the predetermined area and the peripheral area;
A detection apparatus comprising: train identification means for identifying whether an object is a train when the object enters the peripheral area.     The predetermined region is a railroad crossing, and the peripheral region is adjacent to the predetermined region in an extension direction of a line laid so as to pass through the predetermined region. The detection device described. A predetermined region and a peripheral region adjacent to the predetermined region are scanned, three-dimensional radar information is obtained from distance information detected by the laser radar and information on the scanning direction, and the predetermined region is obtained from the three-dimensional radar information. A detection method for detecting an object existing in a region and the surrounding region,
A detection method characterized by recognizing the predetermined area and the surrounding area, and identifying whether the object is a train when the object enters the surrounding area.

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