JP2800934B2 - Moving object detection method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting the passage of a moving object, and more particularly, to a method for detecting the passage of a moving object moving within a control area such as a work site at a predetermined position in the control area. It relates to a passage detection method.

[0002]

2. Description of the Related Art In order to manage the location of a moving object such as a person or a vehicle moving in a management area such as a construction site, a location management method for each area using an identification card which can be read separately has been proposed. In this area-based location management method, the management area is divided into a plurality of areas, an identification card that can be read separately is attached to each of the moving objects that enter and exit the management area, and the movement between the areas is provided with identification card reading means. In this case, the area where each mobile unit is located is managed by identifying the mobile units passing through each of the entrances and exits. An example of the remote reading system is an electromagnetic induction type non-contact data carrier system. In this case, an identification signal is transmitted to an identification card by electromagnetic induction based on radio waves from the reading unit, and the identification signal is read by the reading unit. The non-contact data carrier system of the electromagnetic induction type has a feature that the directivity is weak and the change in the transmission distance is small even if the relative direction between the identification card and the reading means changes.

Referring to FIG. 5, a method of detecting the passage of a moving body at an entrance by an electromagnetic induction method will be briefly described. Although the illustrated example shows a case where the moving body 1 is a person, the passage can be similarly detected when the moving body 1 is a vehicle or the like. In order to manage the location of each area, it is indispensable to not only identify the moving body 1 at each entrance but also detect the passing direction thereof. In the illustrated example, a pair of reading means 3 is arranged on both sides of the passage 5 of the entrance and exit, and a pair of photoelectric detection devices 15 are provided at the front and rear of the reading means 3 as viewed from the entrance and exit direction. Each photoelectric detection device 15 has a light source 8 of a light beam intersecting with the passage 5 and a photoelectric switch 9 for detecting the light beam. The photoelectric detection device 15 photoelectrically reflects the reflected light from the reflector 10 facing the light source 8 through the passage 5. This is detected by the expression switch 9. For example, when the moving body 1 having the identification card 2 mounted in the helmet 11 passes through the entrance / exit passage 5, the light detection by each photoelectric switch 9 is sequentially blocked, and the light blocking detection by the pair of photoelectric switches 9 (hereinafter referred to as "light blocking"). , The light beam may not be detected), the passing direction of the moving body 1 can be determined. The movement of each moving body 1 between the areas is detected from the passing direction of the moving body 1 and the contents of the identification card 2 by the reading means 3. In the drawing, reference numeral 6 denotes a readable area of the identification card 2 formed by the pair of reading means 3.

[0004]

However, the method of judging the passing direction of the moving body 1 from the order of non-detection of the light beam by the pair of photoelectric detectors 15 is based on the positional relationship between the reading means 3 and the photoelectric detector 15. There is a difficult problem. For example, when the distance between the pair of photoelectric detection devices 15 is wide, two or more moving objects 1 may enter between them, and when the moving object 1 enters between the pair of photoelectric detection devices 15 and returns without passing through. There is a problem that is difficult to judge.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for detecting the passage of a moving object which reliably detects the passage of each moving object.

[0006]

SUMMARY OF THE INVENTION The present inventor has determined that the passing direction of a moving body is determined by detecting the first light beam of one of the photoelectric switches after the simultaneous non-detection of the light beam by the pair of photoelectric switches. It has been noticed that the above-described problem that occurs when the determination is made based on the order of non-light detection by the photoelectric detection device can be solved.

Referring to the embodiment of FIG. 1, in the moving object passing detection method according to the present invention, a separately readable identification card 2 attached to each moving object 1 is provided at a predetermined position of a passage 5 of the moving object 1. In the method for detecting the passage of the moving body 1 by the reading means 3 of the identification card 2, a pair of light beams intersecting the passage 5 at the predetermined position with a space in the traveling direction sufficiently smaller than the width of the moving body 1 itself in the traveling direction. A pair of photoelectric switches 9a and 9b for detecting the light sources 8a and 8b emitting the light beams 7a and 7b and the light beams 7a and 7b respectively are provided, and one of the photoelectric switches 9a after the simultaneous non-light detection of both the photoelectric switches 9a and 9b. Or
At the time of the first ray detection by 9b, the passing direction of the moving body 1 is determined, and at the time of the passing direction determination, the identification card 2 of the moving body 1 is read by the reading means 3.

Preferably, the central portion of the reading means 3 faces the portion between the pair of light beams 7a and 7b of the passage 5, and a central reading portion 4b is provided at the central portion thereof to advance the moving body 1 in the passage 5. Adjacent reading sections 4a and 4c are provided before and after the central reading section 4b along the direction, respectively.
Moving body 1 by the adjacent reading unit 4a or 4c on the front side
Is read.

[0009]

The operation of the present invention will be described with reference to the embodiment shown in FIG. However, the present invention can be applied to a moving body 1 other than a person. The identification card 2 of the present invention can be an electromagnetic induction type card that transmits an identification signal readable by the reading means 3 by electromagnetic induction based on radio waves from the reading means 3, for example. In the illustrated example, the reading means 3 is arranged above the moving body 1 passing therethrough so as to face the passage 5, but the reading means 3 is arranged as shown in FIG. Other arrangements that pass through the region 6 can be used. A pair of light sources 8a emitting light beams 7a and 7b are provided at the center of the reading area 6 of the reading means 3 when viewed from the direction of travel of the moving body 1.
8b and a pair of photoelectric switches 9a and 9b for detecting the light beams 7a and 7b, respectively. The distance between the light beams 7a and 7b is made sufficiently shorter than the width of the moving body 1 in the traveling direction, that is, the length from the front end to the rear end of the moving body 1 in the traveling direction.
The light beam detection by 9b can be simultaneously blocked by the mobile unit 1. The illustrated example is a pair of photoelectric detection devices that detect reflected light beams 7a and 7b from a reflection plate 10 with photoelectric switches 9a and 9b.
15a and 15b are shown. However, the light sources 7a and 7b and the photoelectric switches 8a and 8b used in the present invention are not limited to the illustrated photoelectric detectors 15a and 15b using the reflector 10.

FIG. 2A is a side view of the passage 5 provided with the reading means 3 and the pair of photoelectric switches 9a and 9b.
2 (B) to 2 (F) show changes over time in the light beam detection operation by the pair of photoelectric switches 9a and 9b as the vehicle 1 passes.
In the drawing, the symbol "ON" indicates the light non-detection operation by the photoelectric switch, and the symbol "OFF" indicates the light detection operation. When the moving body 1 passes from the photoelectric switch 9a side to the 9b side without returning, after the state of FIG. 2B in which the pair of photoelectric switches 9a and 9b are both OFF, as shown in FIG. First, the photoelectric switch 9a is turned on first,
Next, FIG. 2D in which the photoelectric switches 9a and 9b are simultaneously turned on.
State. In the present invention, after one of the photoelectric switches 9a or 9b is turned OFF after the state of FIG. 2D, the passing direction of the moving body 1 is determined from ON / OFF of each of the photoelectric switches 9a and 9b. . For example, when only one photoelectric switch 9a is turned off in FIG.
It is determined that the signal has passed from the 9a side to the ON photoelectric switch 9b side.

The distance between the pair of light beams 7a and 7b can be widened as long as the state shown in FIG. Below, the state of FIG. 2E can be made as narrow as possible to detect. For example, when the moving body 1 is a person, two light beams
The distance between 7a and 7b can be about 3 cm.

FIG. 3 shows a change over time in the light beam detection operation of the photoelectric switches 9a and 9b when the moving body 1 returns in the middle of passage. 3 (A) to 3 (C) correspond to FIGS. 2 (A), 2 (C) and 2 (D), respectively. In FIG. Represented by the symbol OFF. According to the present invention, when the moving body 1 returns from the state of FIG. 3C in which the pair of photoelectric switches 9a and 9b simultaneously detect no light, only one of the photoelectric switches 9b is turned off.
At the time point (D), it can be determined that the moving body 1 has passed from the photoelectric switch 9b to the side 9a. When the moving body 1 returns from the state shown in FIG. 3B in which only one of the photoelectric switches 9a is turned on, the passing direction is determined because the simultaneous light beam non-detection by the pair of photoelectric switches 9a and 9b does not occur. Although it cannot be obtained, since ON and OFF are detected only by one of the photoelectric switches 9a, it is possible to easily detect the backward movement of the moving body 1.

As described above, according to the present invention, the passing direction of the moving body is determined when one of the photoelectric switches is turned off after the other is turned on at the same time, so that the pair of photoelectric switches is turned on. The problem in the prior art in which the passing direction is determined from the order of Further, if the identification card 2 is read by the reading means 3 at the time of the passing direction determination, the time difference between the passing direction determination and the reading of the identification card 2 can be eliminated, and the passing detection for each moving object 1 can be reliably performed. Can be.

Accordingly, the object of the present invention is to provide a "method of detecting the passage of a moving object for surely detecting the passage of each moving object".

Preferably, as shown in FIG. 1 (B), the reading means 3 is provided with a central reading portion 4b and adjacent reading portions 4a and 4c along the traveling direction of the moving body 1, so that when the passing direction is determined, the front side of the passing direction is determined. The identification card 2 of the moving body 1 is read by an adjacent reading unit, 4c in this case. Another moving body 1a following the moving body 1
Even if (not shown) enters the reading area 6, the subsequent mobile unit 1a is not immediately below the adjacent reading unit 4c, and the adjacent reading unit 4c can read the identification card 2 of the subsequent mobile unit 1. Since there is no moving object, the front and rear moving bodies 1 and 1a can be identified respectively.

[0016]

FIG. 4 shows a central reading section as shown in FIG.
An example of a flow chart of passage detection by the reading means 3 provided with 4b and adjacent reading sections 4a and 4c is shown. Each of the reading sections 4a, 4b, and 4c independently reads the identification card 2 immediately below.
Steps 401 to 404a indicate the reading operation by the adjacent reading units 4a and 4c, and indicate that the reading by the adjacent reading units 4a and 4c is repeated until the pair of photoelectric switches 9a and 9b simultaneously detects no light. In step 402, identification card 2
Judge the presence or absence of reading, if yes, step 40
In step 3, the contents of the identification card 2 are stored in the pre-passage reading memory 13. The read-before-pass memory 13 can be provided corresponding to each of the adjacent reading sections 4a and 4c, for example, as shown in FIG. In step 404, the non-light detection by the photoelectric switch 9a or 9b is determined.If both light rays are being detected, the process returns to step 401. It is determined whether simultaneous light beam non-detection by the switches 9a and 9b has occurred. It is determined that the passage of the moving object 1 has started due to the simultaneous light beam non-detection, and the process proceeds to step 405.

Steps 405 to 408 indicate that the reading by the central reading unit 4b is repeated during the passage of the moving body 1. In step 406, it is determined whether or not the identification card 2 has been read. If the identification card 2 has been read, the contents of the identification card 2 are stored in the passage memory 14 (see FIG. 1A) in step 407. At step 408, the end of the interruption detection by one of the photoelectric switches 9b or 9a, that is, the light beam detection is determined in step 408, and the reading operation is repeated until the light beam is detected (step 405). Determine the orientation.

After judging the passing direction of the moving body 1, step 410
Then, the identification card 2 is read by the adjacent reading section 4c on the front side in the passing direction. At step 411, the presence or absence of reading is determined, and if there is reading, the mobile unit 1 is identified from the read contents (step 412). If the identification card 2 cannot be read due to a reason such as the passing speed of the moving body 1 being high, a step is taken.
The process proceeds to steps 413 to 414, and the moving body 1 is identified from the contents stored in the passage reading memory 14 (step 414). Further, if there is no stored data in the passage reading memory 14, the process proceeds from step 413 to steps 415 to 416, and the moving object 1 is read from the contents stored in the reading memory 13 before passage corresponding to the adjacent reading section 4a on the rear side in the passage direction. Is identified (step 416).
If there is no stored data in the read-before-pass memory 13, it is determined that the mobile 1 to which the identification card 2 is not attached has passed (step 417). After the identification of the moving object 1 that has passed, the reading memory 13 before passing and the reading memory 14 while passing
Is erased, and the flow returns to step 401 to prepare for the detection of the passage of the next mobile unit 1.

Even if the reading means 3 is not provided with the central reading part 4b and the adjacent reading parts 4a and 4c, the passage detection using the passage reading memory 14 can be performed. That is, after simultaneous non-detection of light beams by the pair of photoelectric switches 9a and 9b and before detection of light beams by one of the photoelectric switches 9a and 9b, the contents of the identification card 2 read by the reading means 3 are stored in the reading memory 14 during passage. In this way, even if the identification card 2 cannot be read when the passing direction is determined, each mobile unit 1 can be identified using the contents stored in the passing reading memory 14.

[0020]

As described above in detail, the method for detecting the passage of a moving object according to the present invention comprises two light beams intersecting with a passage at an interval in the traveling direction sufficiently smaller than the width of the moving object in the traveling direction. Are detected by a pair of photoelectric switches, respectively, and the passing direction of the moving body is determined at the time of the first light ray detection by one of the photoelectric switches after the simultaneous non-detection of the light rays by the pair of photoelectric switches. Play.

(1) Even if the moving body has returned while passing, it is possible to easily determine that the moving body has returned. (2) Since the time difference between the determination of the passing direction and the reading of the identification card can be eliminated, the passing detection for each moving object can be reliably performed. (3) By providing a plurality of reading sections in the reading means along the passing direction, even when a plurality of moving bodies enter the reading area, each of the moving bodies can be read in the same manner as when a single moving body passes. And the direction of passage can be determined.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of one embodiment of the present invention.

FIG. 2 is an explanatory diagram of moving object passage detection according to the present invention.

FIG. 3 is an explanatory diagram of passage detection when a moving body returns.

FIG. 4 is an example of a flow chart of passage detection of the present invention.

FIG. 5 is an explanatory diagram of a conventional passage detection method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Moving body 2 Identification card 3 Reading means 4a, 4c Adjacent reading part 4b Central reading part 5 Passage 6 Reading area 7,7a, 7b Light beam 8,8a, 8b Light source 9,9a, 9b Photoelectric switch 10 Reflector 11 Helmet 12 Controller 13 Reading memory before passing 14 Reading memory during passing 15 Photoelectric detector.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Kazuyoshi Suzuki, Inventor Kashima Construction Co., Ltd. 1-2-7 Moto-Akasaka, Minato-ku, Tokyo (56) References JP-A-4-256100 (JP, A) JP JP-A-5-197856 (JP, A) JP-A-63-61394 (JP, A) JP-A-5-242395 (JP, A) JP-A-4-93500 (JP, A) JP-A-6-111179 (JP , A) (58) Field surveyed (Int.Cl. ⁶ , DB name) G08G 1/065

Claims (5)

(57) [Claims] 1. A method of detecting passage of a moving body, wherein the identification card attached to each moving body and which can be read separately is read by means for reading the identification card provided at a predetermined position in a passage of the moving body. A light source that emits a pair of light beams that intersect the passage at a traffic direction interval that is sufficiently smaller than the width of the moving object itself, and a pair of photoelectric switches that respectively detect the light beams. A moving body that determines the passing direction of the moving body at the time of the first light beam detection by one of the photoelectric switches after the simultaneous non-detection of the light beam, and reads the identification card of the moving body by the reading unit when the passing direction is determined. Pass detection method. 2. The identification card according to claim 1, wherein said identification card is read by said reading means before the first light beam detection by one of the photoelectric switches after the light beam is not simultaneously detected by the two photoelectric switches. When the identification card cannot be read at the time of the passing direction determination, the passage of the moving object is detected by the content stored in the passing memory and the passing direction. A method of detecting the passage of moving objects. 3. A passage detecting method according to claim 1, wherein a central portion of said reading means faces a portion of said passage sandwiched between said pair of light beams, and a central reading portion is provided at a central portion thereof. Adjacent reading sections are provided before and after the central reading section along the traveling direction of the moving body, and the identification card of the moving body is read by the adjacent reading section on the front side in the passing direction of the reading means when the passing direction is determined. A method for detecting the passage of a moving object. 4. A passage detecting method according to claim 3, wherein the central reading unit of said reading means reads the first light beam by one of the photoelectric switches after the light beam is not detected simultaneously by the two photoelectric switches. The content of the identification card is stored in the passage reading memory, and when the identification card cannot be read at the time of the passing direction determination, the passing of the moving object is performed based on the content stored in the passing memory and the passing direction. A method for detecting the passage of a moving object by detecting 5. The pre-passage reading memory according to claim 4, wherein the latest contents of the identification card read by the adjacent reading section of the reading means before the light beam is not detected simultaneously by the two photoelectric switches. If the identification card cannot be read at the time of the passing direction determination and there is no content stored in the passing reading memory, the reading is performed by the adjacent reading unit on the rear side in the passing direction and the read before passing memory is read. A method for detecting the passage of a moving object, comprising detecting passage of the moving object based on stored content and the passing direction.