JP6369831B2 - Vehicle detection device, vehicle detection method, and program - Google Patents

Description

  The present invention relates to a vehicle detection device, a vehicle detection method, and a program.

  In a toll collection facility on a toll road, a vehicle detection device for detecting entry and exit of a vehicle is installed. Such a vehicle detection device includes, for example, a plurality of pairs of a light projecting unit and a light receiving unit. In this case, each of the plurality of light projecting units projects a light beam, and each of the plurality of light receiving units receives a light beam corresponding to each light projecting unit. According to such a vehicle detection device, when the vehicle enters between the pair of the light projecting unit and the light receiving unit, the light beam connecting the light projecting unit and the light receiving unit is shielded, and the light beam corresponding to the shielded light beam is supported. The approach of the vehicle can be detected based on the detection signal from the light receiving unit.

  Such a vehicle detection device may erroneously recognize that the vehicle has passed if at least one of the pair of light projecting unit and light receiving unit is shielded by foreign matter such as dust or snow. Therefore, there has been proposed a vehicle detection device that can distinguish between a case where a light beam connecting a pair of light projecting units and a light receiving unit is shielded by a foreign object and a case where the light beam is shielded by passage of a vehicle (for example, a patent). Reference 1).

  In addition, a “separation process” may be performed in which a light receiving unit corresponding to a light beam blocked by a foreign object is temporarily excluded from a target used for vehicle detection. In this case, the detection signal from the separated light receiving unit does not contribute to the vehicle passage detection process. For example, the vehicle detection device separates a light receiving unit corresponding to a light ray that remains blocked for a certain period of time.

Japanese Patent Laid-Open No. 10-334294

  In toll collection facilities where vehicle detection devices are installed, not only the type of vehicle and the shape of the vehicle, but also the presence or absence of a towed vehicle, when the vehicle is stopped, when it is blocked by foreign matter such as dust and snow, etc. Various situations are assumed. In the detection algorithm in the conventional vehicle detection device, it is difficult to accurately separate such various situations according to the detection signals acquired from the respective light receiving units. That is, the vehicle detection device may not be able to detect a passing vehicle with high accuracy.

  An object of the present invention is to provide a vehicle detection device, a vehicle detection method, and a program that can accurately detect the passage of a vehicle.

In one aspect of the present invention, a plurality of light projecting units (S1) that are arranged side by side in the height direction and project a light beam, and a plurality of the light projecting units (S1) are disposed to correspond to the light beam. Receiving a plurality of light receiving units (S2) capable of receiving light and detection signals indicating presence / absence of light received by the plurality of light receiving units (S2) corresponding to the light beams projected by the plurality of light projecting units; A light-blocking information acquisition unit (21) that determines whether or not a light beam is blocked and acquires a light-blocking region (La) occupied by the light-receiving unit corresponding to the light beam that is blocked among the plurality of light-receiving units (S2). ) And a light-shielding area change (D) indicating a temporal change of the light-shielding area (La) acquired by the light-shielding information acquisition unit (21). A standard change pattern (Dref) that defines the conditions of change If appropriate in a determined vehicle determining unit vehicle passes (22), a vehicle detection apparatus comprising a (1).
According to such a configuration, the vehicle detection device has a predetermined change pattern in which the shading area change indicating the temporal change of the shading area (change that occurs with time) is a predetermined change pattern. Since the passage of the vehicle is detected according to whether or not the condition of the temporal change of the light-shielding region that accompanies is matched with the defined standard change pattern, the passage of the vehicle can be detected with high accuracy.

Further, according to one aspect of the present invention, in the vehicle detection device described above, the vehicle determination unit may include a change amount per unit time of the number of light receiving units belonging to the light shielding region and a value defined in the standard change pattern. Based on the comparison with the determination threshold values (ΔNth1, Nth1, ΔNth2, Nth2) determined according to the vehicle body shape of the vehicle, it is determined whether or not the change in the light shielding area matches the standard change pattern. It is characterized by.
According to such a configuration, the vehicle detection device determines that the change in the light shielding area is the amount of change that satisfies a predetermined condition corresponding to the shape of the vehicle body of the passing vehicle. It is determined whether or not the change pattern is met. Therefore, it is possible to accurately determine whether or not the light-shielded vehicle is a passing vehicle.

Further, according to one aspect of the present invention, in the above-described vehicle detection device, the change in the light shielding area is one of the standard change patterns, and a condition for the temporal change of the light shielding area that occurs as the vehicle enters is defined. When the vehicle entry pattern (Dref1) is met, it is determined that the vehicle has entered, and the shading area change is one of the standard change patterns and occurs with the exit of the vehicle. It is characterized in that it is determined that the vehicle has exited when the condition of the dynamic change conforms to the defined vehicle exit pattern (Dref2).
According to such a configuration, the vehicle detection device determines that the vehicle has entered when the light shielding area change satisfies the condition defined in the vehicle entry pattern, and the condition in which the light shielding area change is defined in the vehicle exit pattern. If the condition is satisfied, it is determined that the vehicle has left. Thus, for example, even if the vehicle stops after the vehicle enters, it is not determined that the vehicle has passed unless it is determined that the vehicle has left. Accordingly, it is possible to suppress erroneous detection of the passage of the vehicle.

Further, one aspect of the present invention is the above-described vehicle detection device, in which the light shielding area change is adapted to the vehicle exit pattern, and the light shielding area change is one of the standard change patterns. And determining that the vehicle is a tow vehicle when a condition for temporal change of the light-shielding region caused by the passing of the tow vehicle conforms to a prescribed tow vehicle passing pattern (Dref3). .
According to such a configuration, after the change in the light-shielding region satisfies the condition specified in the vehicle exit pattern, the vehicle detection device further pulls the vehicle when the condition specified in the tow vehicle passage pattern is satisfied. Judge that it is a car. As a result, it is possible to determine that the passing vehicle is a towed vehicle, so that it is possible to suppress erroneous detection of the passing of the vehicle due to the towed vehicle being connected to the towed vehicle. it can.

According to another aspect of the present invention, in the above-described vehicle detection device, in the shading area change following the shading area change adapted to the vehicle leaving pattern, the area is defined in the towing vehicle passage pattern and Based on whether or not the light beam (Lj) belonging to the region corresponding to the connecting portion (J) is shielded, it is determined whether or not the change in the light shielding region matches the towing vehicle passage pattern. To do.
According to such a configuration, the vehicle detection device shields light beams belonging to the region assumed to be provided with the connecting portion as a temporal change of the light shielding region assumed when the towing vehicle passes. It is determined that the passed vehicle is a tow vehicle. Therefore, it can be accurately determined whether or not the passing vehicle is a towing vehicle.

One embodiment of the present invention is a case where the change in the light-shielding region does not match the standard change pattern, and further, the light-shielding region change with time is caused by the light-shielding region change being shielded by foreign matter. When it is determined that the light beam is shielded by the foreign matter and the foreign matter determination unit (231) that determines that the light ray is shielded by the foreign matter when the change condition conforms to the prescribed foreign matter adhesion pattern (Di) And a separation processing unit (232) for excluding a light receiving unit corresponding to the light beam that has been shielded from a plurality of the light receiving units from being detected by the light shielding information acquiring unit.
According to such a configuration, the vehicle detection device determines that the light beam is blocked by the foreign matter when the change in the light shielding region satisfies the condition defined in the foreign matter adhesion pattern. As a result, it is possible to determine whether or not light is blocked by a foreign object, and it is possible to exclude a light receiving unit corresponding to a light beam blocked by the foreign object from detection targets by the light blocking information acquisition unit. Accordingly, for example, it is possible to prevent the exit from being detected even though the vehicle has exited due to a detection signal from the light receiving unit in which the light beam is blocked by the foreign matter.

Further, according to one aspect of the present invention, in the above-described vehicle detection device, the vehicle type of the vehicle is based on a determination result as to which of the plurality of standard change patterns specified by the vehicle type corresponds to the light shielding region change. It is characterized by identifying.
According to such a configuration, the vehicle detection device can identify the vehicle type for each vehicle that is necessary in the toll collection process.

Further, according to one aspect of the present invention, in the above-described vehicle detection device, a condition for determining whether or not the change in the light shielding area matches the standard change pattern based on speed information indicating a traveling speed of the vehicle. It is characterized by correcting.
According to such a configuration, the vehicle detection device corrects the conditions defined in the standard change pattern so as to be appropriate conditions according to the traveling speed of the vehicle. And the accuracy of determination as to whether or not is compatible.

Further, according to one embodiment of the present invention, a plurality of light emitting units that are arranged side by side in the height direction and project a light beam, and a plurality of light projecting units that are disposed corresponding to each of the plurality of light projecting units and that can receive the light beam. A detection signal indicating presence / absence of light reception in a plurality of light receiving units corresponding to light beams projected by the plurality of light projecting units. Receiving an input, determining whether or not the light beam is shielded, obtaining a light shielding region occupied by a light receiving unit corresponding to the light beam shielded from the plurality of light receiving units; A step of determining that the vehicle has passed when a change in the light-shielding region indicating a temporal change in the light-shielding region matches a standard change pattern in which the temporal change in the light-shielding region caused by the passage of the vehicle is defined; Vehicle detection method with It is.
According to such a configuration, the vehicle detection method has a predetermined change pattern in which the light-shielding region change indicating the temporal change of the light-shielding region is a predetermined change pattern, and the time-dependent change of the light-shielding region caused by the passing of the vehicle. Since the passage of the vehicle is detected according to whether or not the condition matches the defined standard change pattern, the passage of the vehicle can be accurately detected.

Further, according to one embodiment of the present invention, a plurality of light projecting units that are arranged in the height direction and project a light beam, and a plurality of light receiving units that are disposed corresponding to each of the plurality of light projecting units and receive the light beam And receiving a detection signal indicating whether or not the light beams projected by the plurality of light projecting units are received by the corresponding plurality of light receiving units, and shielding the light beams. A light-blocking information acquisition unit that acquires a light-blocking region occupied by the light-receiving unit corresponding to the light-blocked light among the plurality of light-receiving units, and the light-blocking information acquired by the light-blocking information acquisition unit A vehicle determination means for determining that the vehicle has passed when a change in the light-shielding region indicating a temporal change in the region conforms to a standard change pattern in which the temporal change in the light-shielding region that occurs as the vehicle passes is defined; age Is a program to function.
According to such a configuration, in the program, the change in the light-shielding area indicating the change in the light-shielding area with time is a predetermined change pattern, and the condition of the temporal change in the light-shielding area with the passing of the vehicle is set. Since the passage of the vehicle is detected according to whether or not it matches the prescribed standard change pattern, the passage of the vehicle can be detected with high accuracy.

  According to the vehicle detection device, the vehicle detection method, and the program described above, it is possible to accurately detect the passage of the vehicle.

1 is a diagram illustrating an overall configuration of a vehicle detection device according to a first embodiment. It is a figure which shows the function structure of the vehicle detection apparatus which concerns on 1st Embodiment. It is a figure explaining the function of the light-shielding information acquisition part which concerns on 1st Embodiment. It is a figure explaining the light-shielding area change which concerns on 1st Embodiment. It is a 1st figure which shows the processing flow of the detection control part which concerns on 1st Embodiment. It is a 2nd figure which shows the processing flow of the detection control part which concerns on 1st Embodiment. It is a 3rd figure which shows the processing flow of the detection control part which concerns on 1st Embodiment. It is a 4th figure which shows the processing flow of the detection control part which concerns on 1st Embodiment. It is a 5th figure which shows the processing flow of the detection control part which concerns on 1st Embodiment. It is a figure explaining the processing content of the vehicle determination part which concerns on 1st Embodiment. It is the 1st figure explaining the operation effect of the detection control part concerning a 1st embodiment. It is the 2nd figure explaining the operation effect of the detection control part concerning a 1st embodiment. It is a figure explaining the processing content of the vehicle determination part which concerns on the modification of 1st Embodiment.

<First Embodiment>
(overall structure)
FIG. 1 is a diagram illustrating an overall configuration of a vehicle detection device according to the first embodiment.
As shown in FIG. 1, the vehicle detection device 1 includes a vehicle detection unit 10 and a detection control unit 20. The vehicle detection unit 10 includes a light projecting tower 101 and a light receiving tower 102.

The light projecting tower 101 and the light receiving tower 102 of the vehicle detection unit 10 are at the same position in the lane direction (± X direction) of the lane L, and are on both sides (the side on the + Y direction side or the side on the −Y direction side) of the lane L. Installed on different sides of the side). The light projecting tower 101 and the light receiving tower 102 are formed in a rectangular shape extending in the height direction (± Z direction) and have surfaces facing each other.
On the surface of the light projecting tower 101 facing the light receiving tower 102, light projecting portions S1 that project a light beam P (for example, infrared light) of a predetermined wavelength toward the light receiving tower 102 are equally spaced in the height direction. Are arranged side by side.
On the other hand, on the surface of the light receiving tower 102 facing the light projecting tower 101, a plurality of light receiving sections S2 for detecting the reception of the light beam P projected by the light projecting section S1 are arranged at equal intervals in the height direction. Yes. Each light receiving part S2 is arranged so as to have a one-to-one correspondence with each of the light projecting parts S1, and is capable of receiving the light beam P projected by the corresponding light projecting part S1. Each light receiving unit S2 continuously outputs a detection signal corresponding to whether the light beam P projected from the corresponding light projecting unit S1 is shielded (shielded state) or not (non-shielded state). doing. Hereinafter, a line that connects each of the corresponding light projecting unit S1 and S2 that receives light and that overlaps the light ray P is also referred to as an “optical axis”.
According to the vehicle detection unit 10 having the above-described configuration, when the vehicle A exists at the same position in the lane direction as the light projecting tower 101 and the light receiving tower 102, a predetermined region in the height direction (to be described later) is determined by the vehicle body of the vehicle A. In the light shielding region), the light beam P projected from the light projecting unit S1 to the light receiving unit S2 is shielded (see FIG. 1). The vehicle detection device 1 detects the passage of the vehicle A based on the detection signal output from the light receiving unit S2. In the present embodiment, “passing” refers to a series of time from when the traveling vehicle A enters the position in the lane direction where the light projecting tower 101 and the light receiving tower 102 of the vehicle detection unit 10 are arranged to exit. Refers to driving.

  The detection control unit 20 governs the overall operation of the vehicle detection device 1. In the present embodiment, the detection control unit 20 is a CPU (Central Processing Unit) and operates based on a program read into a predetermined storage area. The detection control unit 20 that is a CPU is mounted on a device or the like provided on the side of the lane L. When the detection control unit 20 inputs the detection signal input from the vehicle detection unit 10, determines whether the vehicle A has passed based on the detection signal, and determines that the vehicle A has passed. In addition, various other devices constituting the toll collection facility (for example, electronic toll collection system (ETC: Electronic Toll Collection System, also referred to as "automatic toll collection system")) and opening / closing A start control device having a bar).

  The vehicle detection apparatus 1 having the above-described configuration is mainly used in a toll collection facility provided at the entrance or exit of a toll road, and detects the passage (entrance and exit) of one vehicle A traveling in the lane L. To do. Thereby, cooperation operation | movement of the various apparatuses which comprise a fee collection facility is implement | achieved.

(Functional configuration of vehicle detection device)
FIG. 2 is a diagram illustrating a functional configuration of the vehicle detection device according to the first embodiment.
As illustrated in FIG. 2, the detection control unit 20 of the vehicle detection device 1 according to the first embodiment includes a light shielding information acquisition unit 21, a vehicle determination unit 22, and a foreign object handling processing unit 23. .
The light shielding information acquisition unit 21 receives an input of a detection signal indicating whether or not the light beams P projected by the plurality of light projecting units S1 are received by the corresponding plurality of light receiving units S2, and the light beams P It is determined whether or not light is shielded between the part S1 and the corresponding light receiving part S2. Further, the light shielding information acquisition unit 21 acquires a predetermined light shielding region based on the determination result of whether or not the light beam P is shielded. Here, the light shielding region is a predetermined region in the height direction occupied by the light receiving unit S2 corresponding to the light beam P that is shielded from the plurality of light receiving units S2.
In the vehicle determination unit 22, the light-shielding region change D indicating the change over time of the light-shielding region La (FIG. 3) acquired by the light-shielding information acquisition unit 21 (change that occurs with the passage of time) conforms to a predetermined standard change pattern Dref. It is determined whether or not to do. When the light-shielding region change D matches the standard change pattern Dref, the vehicle determination unit 22 determines that the vehicle A (FIG. 1) has passed between the light projecting tower 101 and the light receiving tower 102. Here, the standard change pattern Dref is information that is defined in advance, and is information that defines conditions for temporal change of the light-shielding region La that occurs as the vehicle A passes through the vehicle detection unit 10. In other words, the standard change pattern Dref defines a condition for determining whether the temporal change of the light shielding area acquired by the light shielding information acquisition unit 21 is caused by the passage of the vehicle A. The The standard change pattern Dref includes a vehicle approach pattern Dref1, a vehicle exit pattern Dref2, and a tow vehicle passage pattern Dref3, which will be described later.
When the vehicle determination unit 22 detects the passage of the vehicle A (the entry to the vehicle detection unit 10 and the departure from the vehicle detection unit 10), the vehicle determination unit 22 configures the toll collection facility that the vehicle A has passed. Notify various devices.
The foreign matter handling unit 23 performs a predetermined foreign matter handling process when the light shielding region change D does not match the standard change pattern Dref. Here, the foreign substance handling process is specifically a determination process by the foreign substance determination unit 231 and a separation process by the separation processing unit 232.

When the light shielding region change D does not match the standard change pattern Dref, the foreign matter determination unit 231 further determines whether or not the light shielding region change D matches the foreign matter adhesion pattern Di. The foreign matter determination unit 231 determines that the predetermined light beam P is shielded by the foreign matter when the light shielding region change D matches the foreign matter adhesion pattern Di. Here, the foreign substance adhesion pattern Di is information defined in advance, and is information defining conditions for temporal change of the light shielding region caused by light shielding by foreign substances such as dust and snow. That is, the foreign matter adhesion pattern Di defines a condition for determining whether or not the temporal change of the light shielding area acquired by the light shielding information acquisition unit 21 is caused by the adhesion of foreign matter.
When it is determined that the light beam P is blocked by the foreign matter, the separation processing unit 232 blocks the light receiving unit S2 corresponding to the light beam P that is blocked at the time of the determination from among the plurality of light receiving units S2. A separation process for excluding the information from the detection target by the information acquisition unit 21 is performed.

FIG. 3 is a diagram for explaining the function of the shading information acquisition unit according to the first embodiment.
A process in which the light shielding information acquisition unit 21 specifies the light shielding area La will be described with reference to FIG.
FIG. 3 shows a correspondence relationship between the vehicle body shape (side shape) of the vehicle A and the light blocking state of the light beam P. As shown in FIG. 3, when the vehicle A is passing between the light projecting tower 101 and the light receiving tower 102 on the lane L (after entering and before leaving), the light receiving units S <b> 2 arranged in the light receiving tower 102 The light receiving part S2 in a state where the light beam P is shielded by the vehicle body of the vehicle A (light shielding state) and the light receiving part S2 in a state where the light beam P is not shielded (non-light shielding state) exist. Each light receiving unit S2 outputs a detection signal PL indicating that it is in a light-shielding state or a detection signal PH indicating that it is in a non-light-shielding state based on whether or not the light beam P is received. The light-shielding information acquisition unit 21 receives input of detection signals from each light-receiving unit S2, and identifies the light-receiving unit S2 that outputs the light-shielding detection signal PL from among the plurality of light-receiving units S2, thereby receiving the light-receiving unit in the light-shielding state. The light shielding area La, which is the area in the height direction occupied by S2, is specified.
The light shielding information acquisition unit 21 performs light shielding every sampling time Δt based on a detection signal from the light receiving unit S2 continuously input per predetermined unit time (sampling time Δt, for example, Δt = 10 msec). The area La is acquired.

FIG. 4 is a diagram for explaining a light shielding region change pattern according to the first embodiment.
The light shielding region La shown in FIG. 3 changes as the vehicle A passes through the vehicle detection unit 10. As shown in FIG. 4, the temporal change of the light-shielding region La acquired every sampling time Δt corresponds to the vehicle body shape (side surface shape) of the passing vehicle A. For example, the light shielding region La at a certain time t0 is a predetermined region in the height direction corresponding to the head position of the vehicle body, and the light shielding region La at time t1 (= t0 + Δt) after the sampling time Δt has elapsed from the time t0 is the sampling time Δt. A predetermined area in the height direction corresponding to a position on the rear side of the vehicle with respect to the head position of the vehicle body is equivalent to the amount moved during the period. At this time, a temporal change ΔLa of the light shielding region La occurs during the sampling time Δt. In the present embodiment, the light shielding region change D is information indicating the temporal change of the light shielding region La that occurs as the vehicle A passes as described above.

(Main processing flow of the detection control unit)
FIG. 5 is a first diagram illustrating a processing flow of the detection control unit according to the first embodiment.
Next, the overall flow (main processing flow) of processing performed by the detection control unit 20 will be described in order with reference to FIG. As a premise, during execution of the main processing flow, the light P is constantly projected from the plurality of light projecting units S1 arranged in the light projecting tower 101 of the vehicle detection unit 10.

First, the shading information acquisition unit 21 of the detection control unit 20 receives an input of a detection signal from each of the plurality of light receiving units S2 arranged in the light receiving tower 102 of the vehicle detection unit 10, and is there a light beam P that is shielded? It is determined whether or not (step S01). When there is no light ray P that is shielded from light, the light shielding information acquisition unit 21 repeatedly performs the same process (step S01: NO).
When even one light-shielded light ray P is detected (step S01: YES), the detection control unit 20 performs “vehicle approach pattern determination process” (step S02). The vehicle entry pattern determination process is a determination as to whether or not a light-shielding area change D indicating a temporal change in a height-direction area (that is, a light-shielding area) occupied by the light-shielded light ray P matches the vehicle entry pattern Dref1. This is the process to be performed. The vehicle approach pattern Dref1 is one of the standard change patterns Dref defined in advance, and is information that defines the conditions for the temporal change of the light-shielding area La that occurs when the vehicle A “enters”. is there.
Details of the vehicle entry pattern determination process will be described with reference to FIG.

When the light-shielding region change D conforms to the vehicle entry pattern Dref1 (step SS03: YES), the detection control unit 20 detects that the vehicle A has entered the vehicle detection unit 10, and makes the entry of the vehicle A into various devices. Notification is made (step S04). Thereby, the toll collection facility provided with the vehicle detection device 1 can perform a cooperative operation (for example, start of ETC wireless communication processing) according to the approach of the vehicle A.
On the other hand, when the light-shielding region change D does not conform to the vehicle approach pattern Dref1 (step S03: NO), the detection control unit 20 performs “foreign matter handling processing” (step S05). The foreign matter handling processing is based on whether or not foreign matter such as dust or snow has adhered to the light projecting unit S1 and the light receiving unit S2 based on the determination as to whether or not the light shielding region change D matches the foreign matter adhesion pattern Di described above. And the light receiving unit S2 is disconnected as necessary.
Details of the foreign object handling process will be described with reference to FIG.

When the entry of the vehicle A to the vehicle detection unit 10 is detected in step S04, the detection control unit 20 subsequently performs a “vehicle exit pattern determination process” (step S06). The vehicle exit pattern determination process is a process for determining whether or not the light shielding area change D matches the vehicle exit pattern Dref2. Further, the vehicle exit pattern Dref2 is one of standard change patterns Dref defined in advance, and is information in which conditions for temporal change of the light-shielding area La generated when the vehicle A “exits” are defined. is there.
Details of the processing contents of the vehicle exit pattern determination processing will be described with reference to FIG.

  When the light-shielding region change D does not conform to the vehicle exit pattern Dref2 (step S07: NO), it is determined that the vehicle A that has entered does not exit the vehicle detection unit 10, and step S06 is repeated. For example, when the vehicle A that has entered the vehicle detection unit 10 is stopped while blocking the light beam P in the predetermined area because of traffic jam, step S06 is repeated.

When the light-shielding region change D is adapted to the vehicle exit pattern Dref2 (step S07: YES), the detection control unit 20 subsequently performs “traction vehicle handling processing” (step S08). The tow vehicle handling process determines whether or not the exited vehicle A is a “tow vehicle” based on the determination as to whether or not the shading region change D conforms to the tow vehicle passage pattern Dref3. This is a process for performing exit determination for a tow vehicle. The tow vehicle passage pattern Dref3 is one of the standard change patterns Dref defined in advance, and is information in which conditions for the temporal change of the light-shielding region La generated as the “tow vehicle” passes are defined. It is.
Details of the towing vehicle handling process will be described with reference to FIG.

  When the tow vehicle handling process (step S08) is completed, the detection control unit 20 detects that the vehicle A has left the vehicle detection unit 10, and notifies the various devices of the departure of the vehicle A (step S09). Thereby, the toll collection facility provided with the vehicle detection device 1 can perform a cooperative operation according to the exit of the vehicle A.

  Note that while the toll collection facility is in operation, the detection control unit 20 repeatedly performs the above-described main processing flow (step S01 to step S09).

(Vehicle approach pattern judgment processing)
FIG. 6 is a second diagram illustrating a processing flow of the detection control unit according to the first embodiment.
FIG. 6 shows a detailed processing flow in the vehicle approach pattern determination processing (step S02) in the main processing flow (FIG. 5). Here, the vehicle approach pattern Dref1 includes a condition (light) for determining whether or not the temporal change of the light shielding area acquired by the light shielding information acquisition unit 21 is caused by the “entry” of the vehicle A. A condition relating to the determination process in steps S201 to S203 based on the axis increase number determination threshold ΔNth1 and the optical axis number determination threshold Nth1 is defined.

In the vehicle entry pattern determination process, the light shielding information acquisition unit 21 acquires the light shielding region La (see FIG. 3) based on the detection signal received from each light receiving unit S2 (step S200).
Next, the vehicle determination unit 22 refers to the light shielding region La acquired by the light shielding information acquisition unit 21, and determines whether or not the number of light receiving units S2 belonging to the light shielding region La (the number of light shielding optical axes Na) has increased. Determination is made (step S201). Since the number of light-shielding optical axes Na before shifting to the vehicle approach pattern determination process is zero, the number of light-shielded optical axes Na is always increased in the first step S201 in the vehicle approach pattern determination process (step S201: YES). It is determined.

When the number of light-shielding optical axes Na increases (step S201: YES), the vehicle determination unit 22 further increases the number ΔNa (ΔNa>) that is the amount of change per unit time (sampling time Δt) of the number of light-shielding optical axes Na. It is determined whether or not (0) is greater than or equal to the optical axis increase number determination threshold value ΔNth1 (ΔNth1> 0) (step S202). The optical axis increase number determination threshold value ΔNth1 is set to a value corresponding to the inclination of the front portion of the body shape of a general vehicle passing at a normal approach speed (20 to 30 km / h), for example. Note that the shape of the front part of a bus or truck is not inclined as in general vehicles, but is nearly vertical. Therefore, the increase number ΔNa when the bus or truck enters is larger than the increase number ΔNa when the general vehicle enters. Therefore, by setting the optical axis increase number determination threshold value ΔNth1 according to a general vehicle, it is possible to detect not only the general vehicle but also an entrance of a bus or a truck.
When the number of light shielding optical axes Na has not increased (step S201: NO), or when the number of increases ΔNa is less than the optical axis increase number determination threshold ΔNth1 (step S202: NO), the vehicle determination unit 22 changes the light shielding area. It is determined that D does not conform to the vehicle entry pattern Dref1 (step S204). In this case, since it is assumed that dust, snow, or the like adheres to the light projecting unit S1 or the light receiving unit S2, the detection control unit 20 performs dust handling processing (step S05) via step S03 (FIG. 5). Transition (see FIG. 5).

On the other hand, when the increase number ΔNa (> 0) of the light shielding optical axis number Na is equal to or larger than the optical axis increase number determination threshold value ΔNth1 (step S202: YES), the vehicle determination unit 22 determines that the light shielding optical axis number Na is a predetermined light. It is determined whether or not the axis number determination threshold Nth1 is reached (step S203). The optical axis number determination threshold value Nth1 is set to the number of light-shielding optical axes corresponding to a length (for example, about 1 m) that can determine whether the vehicle body has a normal size or the other.
Note that when the light receiving unit S2 disposed at a position corresponding to the window of the vehicle A receives the light beam P that has passed through the window, the light shielding region La may be obtained separately. In each of steps S202 and S203, the increase number ΔNa of the light-shielding optical axis Na and the light-shielding optical axis number Na to be determined are the light receiving part S2 positioned at the top of the light receiving parts S2 belonging to the light shielding area La, and It is calculated based on the number of light receiving parts S2 included between the light receiving parts S2 located in the lower stage.

  The vehicle determination unit 22 repeats steps S201 to S202 until the light-shielding optical axis number Na becomes equal to or greater than the optical axis number determination threshold Nth1 (step S203: NO). When the light-shielding optical axis number Na becomes equal to or greater than the optical axis number determination threshold Nth1 (step S203: YES), the vehicle determination unit 22 determines that the light-shielding region change D is adapted to the vehicle approach pattern Dref1 (step S205). That is, when the number of light-shielding optical axes Na satisfies all the conditions defined in each of steps S201 to S203, “the light-shielding area change D is adapted to the vehicle approach pattern Dref”.

  The detection control unit 20 obtains a determination result as to whether or not the light shielding region change D is adapted to the vehicle approach pattern Dref1 by the above vehicle approach pattern determination process (steps S200 to S205).

(Foreign matter handling)
FIG. 7 is a third diagram illustrating a processing flow of the detection control unit according to the first embodiment.
FIG. 7 shows a detailed processing flow in the foreign object handling processing (step S05) in the main processing flow (FIG. 5). Here, in the foreign matter adhesion pattern Di, a condition for determining whether or not the temporal change of the light shielding area acquired by the light shielding information acquisition unit 21 is caused by the foreign matter adhesion (steps S501 and S502). ) Is defined.
In the foreign matter handling process, first, the light shielding information acquisition unit 21 acquires the light shielding region La (see FIG. 3) based on the detection signal received from each light receiving unit S2 (step S500).
Subsequently, the foreign matter determination unit 231 determines whether or not there is a change from the previously acquired light shielding region La (step S501). Here, in the first step S501, the foreign matter determination unit 231 compares with the light-shielding region La acquired in step S200 (FIG. 6).
If there is no change in the light-shielding area La (step S501: YES), it is determined whether or not the state without the change has been continuously detected a predetermined number of times (for example, 8 times) (step S502). Here, when the detection is continuously performed a predetermined number of times (step S502: YES), it is determined that foreign matter such as dust or snow has adhered to the light projecting unit S1 or the light receiving unit S2 corresponding to the shielded light beam P. Then, the separation processing unit 232 performs processing (separation processing) for excluding the light receiving unit S2 corresponding to the light beam P that is shielded at this point from the detection target by the light shielding information acquisition unit 21 (step S503).
On the other hand, if there is any change in the light shielding area La in step S501 before the state where there is no change in the light shielding area La is detected for a predetermined number of times in step S502 (step S501: NO), The foreign object handling process is terminated without performing the separation process. Therefore, the separation process is not performed when the attached dust is immediately removed by wind or the like, or when it is light-shielded instantaneously by falling snow or “hail”.

(Vehicle exit pattern determination process)
FIG. 8 is a fourth diagram illustrating a processing flow of the detection control unit according to the first embodiment.
FIG. 8 shows a detailed process flow in the vehicle exit pattern determination process (step S06) in the main process flow (FIG. 5). Here, the vehicle exit pattern Dref2 includes a condition (light) for determining whether the temporal change of the light shielding area acquired by the light shielding information acquisition unit 21 is caused by the “exit” of the vehicle A. A determination process in steps S601 to S603 based on the axis reduction number determination threshold ΔNth2 and the optical axis number determination threshold Nth2 is defined.

In the vehicle exit pattern determination process, the light shielding information acquisition unit 21 acquires the light shielding region La (see FIG. 3) based on the detection signal received from each light receiving unit S2 (step S600).
Next, the vehicle determination unit 22 refers to the light shielding region La acquired by the light shielding information acquisition unit 21 and determines whether or not the number of optical axes P constituting the light shielding region La (the number Na of light shielding optical axes) has decreased. Is determined (step S601).

When the number of light-shielding optical axes Na decreases (step S601: YES), the vehicle determination unit 22 further determines that the number of light-shielding optical axes Na to be decreased ΔNa (ΔNa <0) is the optical axis decrease number determination threshold ΔNth2 (ΔNth2 < 0) It is determined whether or not it is below (step S602). The optical axis reduction number determination threshold value ΔNth2 is set to a value corresponding to the inclination of the rear portion of the body shape of a general vehicle that passes at a normal approach speed (20 to 30 km / h), for example. Note that the shape of the rear part of the bus or truck (in the case of a truck, the rear end of the loading platform) is generally not inclined like a general vehicle, but is nearly vertical. Accordingly, the decrease number ΔNa (<0) when the bus or the truck leaves is smaller than the decrease number ΔNa (<0) when the general vehicle leaves. Therefore, by setting the optical axis reduction number determination threshold value ΔNth2 according to the general vehicle, it is possible to detect not only the general vehicle but also the exit of the bus or the truck.
When the number of light-shielding optical axes Na has not decreased (step S601: NO), or the decrease number ΔNa (<0) is larger than the optical axis decrease number determination threshold value ΔNth2 (<0) (step S602: NO). The vehicle determination unit 22 determines that the light shielding region change D does not conform to the vehicle exit pattern Dref2 (step S604).

  On the other hand, when the decrease number ΔNa (<0) of the light shielding optical axis number Na is equal to or less than the optical axis decrease number determination threshold value ΔNth2 (step S602: YES), the vehicle determination unit 22 determines that the light shielding optical axis number Na is a predetermined light. It is determined whether or not the number of axes determination threshold Nth2 or less is reached (step S603). The optical axis number determination threshold value Nth2 is set to the number of light-shielding optical axes corresponding to a length (for example, about 20 cm) that can determine the exit of a vehicle body having a normal size.

  The vehicle determination unit 22 repeats steps S601 to S602 until the light-shielding optical axis number Na becomes equal to or less than the optical axis number determination threshold Nth2 (step S603: NO). When the light-shielding optical axis number Na becomes equal to or smaller than the optical axis number determination threshold Nth2 (step S603: YES), the vehicle determination unit 22 determines that the light-shielding region change D is adapted to the vehicle exit pattern Dref2 (step S605).

  The detection control unit 20 obtains a determination result as to whether or not the light shielding area change D is adapted to the vehicle exit pattern Dref2 by the above vehicle exit pattern determination process (steps S600 to S605).

(Trucking vehicle handling processing)
FIG. 9 is a fifth diagram illustrating a processing flow of the detection control unit according to the first embodiment.
Moreover, FIG. 10 is a figure explaining the processing content of the vehicle determination part which concerns on 1st Embodiment.
FIG. 9 shows a detailed process flow in the tow vehicle handling process (step S08) in the main process flow (FIG. 5). Here, in the tow vehicle passage pattern Dref3, a condition for determining whether or not the temporal change in the light shielding area acquired by the light shielding information acquisition unit 21 is caused by the passage of the tow vehicle (step S801). , S802).

In the towing vehicle handling process, first, the light shielding information acquisition unit 21 acquires the light shielding region La (see FIG. 3) based on the detection signal received from each light receiving unit S2 (step S800).
Next, the vehicle determination unit 22 determines whether or not the light shielding region La exists in step S800, that is, whether or not the light shielded light ray P exists (step S801). When there is no light shield P (step S801: NO), in step S07 (FIG. 5), it is determined that the vehicle A in which the light shielding area change D conforms to the vehicle exit pattern Dref2 is not a “tow vehicle”. The corresponding process is terminated. In this case, the detection control unit 20 immediately detects that the vehicle A has left the vehicle detection unit 10 and notifies the same (FIG. 5, step S09).

  In step S07, when the light shield P remains even though the light shielding area change D is adapted to the vehicle exit pattern Dref2 (step S801: YES), the vehicle A exiting the vehicle detection unit 10 is the towing vehicle. It is assumed that Therefore, the vehicle determination unit 22 determines whether or not the vehicle A that has exited is a towing vehicle (step S802). The vehicle determination unit 22 determines whether or not the light beam P that is shielded in the light shielding region change D that follows the light shielding region change D that conforms to the vehicle exit pattern Dref2 belongs to the predetermined connecting portion region Lj (FIG. 10). Based on the determination, it is determined whether the vehicle A is a towing vehicle.

  Here, as shown in FIG. 10, the connecting portion region Lj is a height-direction region defined in the towing vehicle passage pattern Dref3 and connects the towed vehicle A and the towed vehicle. This is an area corresponding to J. For example, it is assumed that the tow vehicle A passes through the vehicle detection unit 10 and the light-shielding region change D matches the vehicle exit pattern Dref2 at time t3 (FIG. 5, step S07). However, at this time, since the light ray P that has been shielded remains due to the presence of the connecting portion J (step S801: YES), the vehicle determination unit 22 does not determine that the vehicle A has “retreated”. In this case, the vehicle determination unit 22 determines whether or not the light beam P that has been shielded belongs to a predetermined connection unit region Lj in order to determine whether or not the vehicle A that has exited the vehicle detection unit 10 is a towing vehicle. Is determined (step S802). In the example shown in FIG. 10, in step S802, the light ray P that is shielded at time t4 after the light shielding region change D is matched with the vehicle exit pattern Dref2 (time t3) belongs to the connecting portion region Lj. Therefore, the vehicle determination unit 22 determines that the vehicle A is a tow vehicle (step S802: YES).

  As described above, when the light ray P that has been shielded belongs to the connecting portion region Lj corresponding to the connecting portion J, the vehicle determination unit 22 determines that the vehicle A that has left is a towing vehicle (step). S802: YES). If it is determined that the vehicle A that has exited is a tow vehicle, the vehicle determination unit 22 repeats the processes of steps S800 to S801 until the towed vehicle connected to the vehicle A that is a tow vehicle exits. In this case, when there is no longer the shielded light beam P (step S801: NO), the vehicle determination unit 22 determines that the towed vehicle has been withdrawn, and ends the towed vehicle handling process.

On the other hand, in step S07 (FIG. 5), the light shield P remains even though the light shield region change D matches the vehicle exit pattern Dref2, and the light shield P remains in the connecting portion region Lj. When the vehicle A does not belong to the vehicle (step S802: NO), it is assumed that foreign matter such as dust or mud adheres to the light projecting unit S1 or the light receiving unit S2 as the vehicle A passes.
In this case, the foreign substance handling processing unit 23 determines whether or not the light shielding object is a foreign substance, and performs a separation process as necessary (steps S803 to S806). In addition, since the process of the said step S803-S806 is equivalent to the foreign material response process of step S05 (step S500-S503), description is abbreviate | omitted.

(Function and effect)
According to the vehicle entry pattern determination process (FIG. 6) described above, the vehicle determination unit 22 changes the shading region La over time when the vehicle A enters the vehicle detection unit 10, that is, the slope of the front portion. As a result, the vehicle A is determined to have entered the vehicle detection unit 10 when it reaches a certain height (Na ≧ Nth1) or more while exhibiting a predetermined increasing tendency (ΔNa ≧ ΔNth1). Thus, even if the light ray P is blocked by a foreign object that is not a vehicle, it is not determined that the vehicle has entered unless the conditions defined in the vehicle entry pattern Dref1 are satisfied. Therefore, even when a foreign object such as dust or snow adheres to the light projecting unit S1 or the light receiving unit S2, it is possible to suppress erroneous detection that “the vehicle has entered” due to light shielding by the foreign object.

  Further, according to the above-described vehicle exit pattern determination process (FIG. 8), the vehicle determination unit 22 changes the light-shielding area La over time when the vehicle A exits the vehicle detection unit 10, that is, the rear portion. It is determined that the vehicle A has “retreated” from the vehicle detection unit 10 when the height falls below a considerable height (Na ≦ Nth2) while showing a predetermined decreasing tendency (ΔNa ≦ ΔNth2) according to the slope of the vehicle.

FIG. 11 is a first diagram illustrating the operation and effect of the detection control unit according to the first embodiment.
Here, for example, consider a case where the vehicle A stops at a position between the light projecting tower 101 and the light receiving tower 102 at time t7 as shown in FIG. In this case, as shown in FIG. 11B, the light-shielding region change D of the light-shielding region La acquired sequentially by the light-shielding information acquisition unit 21 hardly changes after the time t7. However, since the light receiving unit S2 corresponding to the position of the boundary α of the side surface shape of the vehicle body repeats light shielding and non-light shielding due to, for example, the operation of the wiper and the vibration of the vehicle body, as shown in FIG. In some cases, a minute change d of the light shielding region La may be detected.

According to the detection control unit 20 according to the present embodiment, the vehicle determination unit 22 detects that the vehicle A has entered the vehicle detection unit 10 at time t6 shown in FIG. 11B (FIG. 5). Step S04). Therefore, even when the vehicle A stops between the light projecting tower 101 and the light receiving tower 102 at time t7 after time t6, the vehicle determination unit 22 determines that the light shielding area change D conforms to the vehicle exit pattern Dref2. Unless it is determined that it has been made, it is not considered that the user has left (FIG. 5, steps S06, S07). Therefore, for example, even if a minute change d of the light shielding region La based on the operation of the wiper or the vibration of the vehicle body occurs while the vehicle A is stopped, the vehicle determination unit 22 uses the minute change d to change the light shielding region change D. It is not determined that the vehicle exit pattern Dref2 is met. Therefore, the vehicle determination unit 22 can suppress erroneous detection that “the vehicle A has left” even when the vehicle A is stopped.
Further, according to the detection control unit 20, since it is detected that the vehicle A has entered at the time t6, it is determined whether or not a foreign object is attached unless the vehicle A is detected to exit ( The foreign object determination process is not performed (FIG. 5, steps S03 to S09). Therefore, even when the same light shielding area La is detected a predetermined number of times or more while the vehicle A is stopped between the light projecting tower 101 and the light receiving tower 102, the light shielding area La is concerned. Does not erroneously determine that the light-receiving unit S2 belonging to is “shielded by foreign matter”. Therefore, the detection control unit 20 can also avoid performing the separation process of the light receiving unit S2 by the separation process based on the erroneous determination.

  Further, according to the above-described foreign matter handling process (FIG. 7), the foreign matter handling processing unit 23 changes with time in the light shielding region La assumed when the foreign matter adheres to the light projecting unit S1 or the light receiving unit S2. It is determined that foreign matter has adhered to the light projecting unit S1 or the light receiving unit S2 by continuously shielding the same light beam P for a predetermined time (predetermined number of sampling times).

FIG. 12 is a second diagram illustrating the operation and effect of the detection control unit according to the first embodiment.
Here, for example, as shown in FIG. 12A, consider a case where foreign matter C such as mud, receipt, fallen leaves, etc. adheres to the light receiving part S2 located at the position β. In this case, since light shielding is detected at time t8 when the foreign object C adheres, the detection control unit 20 performs a vehicle exit pattern determination process (FIG. 5, step S02). However, as a result of determining that the light-shielding region change D based on the adhesion of the foreign matter C does not match the vehicle approach pattern Dref1, the foreign matter handling unit 23 immediately performs the foreign matter handling process (FIG. 5, step S05).
Here, as shown in FIG. 12B, the foreign matter determination unit 231 detects that the light-shielding region La has not changed after the time from time t9 to time t10 (sampling time Δt × 8) ( FIG. 7, steps S501 and S502). As a result, the separation processing unit 232 performs the separation processing of the light receiving unit S2 corresponding to the position β at time t10 (FIG. 7, step S503).
According to the above processing, the detection control unit 20 accurately discriminates between the attached foreign matter C and other factors (falling snow, “hail”, flying birds, insects, etc.). The separation process is performed only by “attachment of foreign matter” in the light projecting unit S1 or the light receiving unit S2. As a result, due to the detection signal from the light receiving unit S2 in which the light beam P is blocked by the foreign matter, the vehicle entry may be erroneously detected, or the vehicle exit may not be detected despite the vehicle leaving. Can be prevented. Also, since the separation process is not performed for momentary and temporary light shielding (due to falling snow, hail, etc.), the number of light receiving parts S2 to be separated is required. It can be minimized, and a decrease in vehicle detection accuracy can be suppressed.

Further, according to the above-described tow vehicle handling process (FIG. 9), the vehicle determination unit 22 changes the shading region La over time assumed when the tow vehicle passes the vehicle detection unit 10, that is, the connecting unit J. It is determined that the vehicle A that has passed is a towing vehicle when the light ray P belonging to the region (the connecting portion region Lj) that is assumed to be disposed is blocked. Thereby, for example, even when the vehicle A stops in a state where the connecting portion J exists between the light projecting tower 101 and the light receiving tower 102 (for example, time t4 shown in FIG. 10), the light is shielded. As long as the light ray P belongs to the region corresponding to the connecting portion J (the connecting portion Lj), the process of separating the light receiving portion S2 corresponding to the light ray P is not performed. Further, the vehicle determination unit 22 does not detect the exit of the vehicle A until the towed vehicle pulled by the vehicle A exits. Therefore, since the tow vehicle and the towed vehicle are regarded as one vehicle, it is possible to suppress misidentification of the number of vehicles A (one or two) passing therethrough.
In this way, after the light-shielding region change D satisfies the condition defined in the vehicle exit pattern Dref2, the vehicle detection device 1 further determines that the vehicle A is in the case where the condition defined in the towing vehicle passage pattern Dref3 is satisfied. It is determined that the vehicle is a towing vehicle. As a result, it is possible to determine that the passing vehicle is a towed vehicle, so that the passing of the vehicle is erroneously detected because the towed vehicle is connected to the towed vehicle (the vehicle is still detected by the vehicle). It is possible to suppress the determination that “passing is completed” in spite of the state of being in the area and not having passed.

  As described above, according to the vehicle detection device 1 according to the present embodiment, the temporal change of the light-shielding region (based on the vehicle entry pattern determination process, the vehicle exit pattern entry process, the foreign object handling process, and the towing vehicle handling process ( Since the passage of the vehicle is detected according to whether or not the light shielding region change D) matches the standard change pattern, the passing vehicle can be detected with high accuracy.

(Modification of the first embodiment)
Note that the specific process flows of the vehicle approach pattern determination process and the vehicle exit pattern determination process shown in FIGS. 6 and 8 are examples, and are not limited to the process flows shown in FIGS. 6 and 8. .

FIG. 13 is a diagram illustrating the processing content of the vehicle determination unit according to the modification of the first embodiment.
The vehicle determination unit 22 according to the modification of the first embodiment is a change pattern of the detection signal of the light receiving unit S2 that changes as the vehicle passes and is recorded in advance (FIG. 13A), While calculating the degree of coincidence with the light-shielding region change D (FIG. 13B) that is actually acquired when passing through the vehicle A, the entry and exit of the vehicle may be detected based on the degree of coincidence. In this case, the change pattern (FIG. 13A) of the detection signal of the light receiving unit S2 recorded in advance corresponds to the standard change pattern Dref.
Also, a plurality of standard change patterns Dref may be recorded in advance for each vehicle type existing in the automobile market or for each vehicle having a typical vehicle body shape, for example. In this case, the vehicle determination unit 22 matches the at least one of the plurality of standard change patterns Dref corresponding to the vehicle type with the light-shielding region change D acquired as the vehicle A enters and leaves. Entry and exit shall be detected. For example, the vehicle determination unit 22 sequentially compares the light shielding area change D sequentially acquired as the vehicle A enters and a plurality of standard change patterns Dref recorded in advance for each vehicle type. Then, a comparison with another standard change pattern Dref is performed. In this case, the vehicle determination unit 22 repeatedly performs comparison until the sequentially obtained shading region change D matches any of the plurality of standard change patterns Dref.
Note that the above-described processing is merely an example, and the vehicle determination unit 22 may determine which standard change pattern Dref the light-shielding region change D conforms to through other different processing. For example, the vehicle determination unit 22 sequentially compares a plurality of standard change patterns Dref with respect to a series of light-shielding region changes D acquired from the entry to exit of the vehicle A, and one completely consistent standard change pattern Dref is identified. The comparison may be repeated until
Further, the vehicle determination unit 22 adapts the light-shielding area change D sequentially acquired from the approach of the vehicle A while repeatedly comparing with a plurality of standard change patterns Dref having a certain “allowable width”. The candidates for the pattern Dref may be narrowed down.

As a method for calculating the degree of coincidence, for example, the vehicle determination unit 22 corresponds to the light shielding region La detected at the beginning (time t11) when the vehicle A enters and the reference time t_ref defined in the standard change pattern Dref. The matching rate p10 with the light shielding region La_ref to be acquired is acquired. The vehicle determination part 22 performs the same process for every sampling time (DELTA) t progress, and acquires ratio p11, p12, ... according to time. Further, the vehicle determination unit 22 sequentially determines whether or not each of the acquired coincidence rates p10, p11, p12,... Is equal to or higher than a predetermined determination threshold, and determines that it is equal to or higher than the determination threshold for a predetermined number of times (for example, , 8 times) When it is continuously satisfied, it is determined that “vehicle A has entered”.
In this case, depending on the traveling speed of the vehicle A, the acquired shading region change D may change. Therefore, the standard change pattern Dref defined in advance may be defined based on the normal speed (20 to 30 km / h) of the vehicle A when entering the toll collection facility.

  Further, according to the above modification, the vehicle determination unit 22 determines whether the light shielding region change D acquired based on the vehicle A entering the vehicle detection unit 10 is any of the plurality of standard change patterns Dref recorded in advance. Can be identified. Therefore, it is possible to specify the category of the vehicle type (ordinary vehicle, large vehicle, extra large vehicle, etc.) to which the vehicle corresponding to the adapted standard change pattern Dref belongs. Using this, the vehicle determination unit 22 is based on the determination result as to which of the plurality of standard change patterns Dref specified by the vehicle type the light-shielding region change D acquired in accordance with the passage of the vehicle A. Thus, the vehicle type of the vehicle A passing through the vehicle detection unit 10 may be identified and notified to other various devices. As a result, it is possible to identify the vehicle type for each vehicle that is necessary in the toll collection process.

Further, the detection control unit 20 may acquire the traveling speed of the vehicle A when the vehicle detection unit 10 passes through vehicle speed measurement means that is separately installed in the toll collection facility. In this case, the vehicle determination unit 22 corrects the determination condition as to whether or not the light-shielding region change D acquired in accordance with the passage of the vehicle A matches the standard change pattern Dref.
Specifically, the vehicle determination unit 22 increases or decreases the optical axis increase number determination threshold value ΔNth1 and the optical axis decrease number determination threshold value ΔNth2 according to the traveling speed of the vehicle A. For example, when the vehicle A passes at a relatively low speed, the temporal change ΔLa (see FIG. 4) of the light shielding region La acquired every sampling time Δt becomes a relatively small value. On the other hand, when the vehicle A passes at a relatively high speed, the temporal change ΔLa of the light shielding region La acquired every sampling time Δt becomes a relatively large value. Therefore, the vehicle determination unit 22 may increase or decrease the optical axis increase number determination threshold value ΔNth1 and the optical axis decrease number determination threshold value ΔNth2 in proportion to the traveling speed of the vehicle A that has acquired the optical axis increase number determination threshold value ΔNth1. By doing so, various conditions (that is, ΔNth1, ΔNth2) defined in the standard change pattern Dref are in real time during the passage of the vehicle A so that the conditions are appropriate according to the traveling speed of the vehicle A. Since the correction is made, it is possible to improve the determination accuracy of whether or not the light-shielding region change D acquired according to the passage of the vehicle A and the standard change pattern Dref are compatible.
The vehicle speed measuring means may be, for example, a general speed measuring device, or a tread board that is installed on the lane L and includes a treading pressure detection sensor that can detect the treading pressure. In the latter case, for example, the vehicle determination unit 22 calculates the speed of the traveling vehicle based on the time difference between the timings at which the step pressure detection signals output from the plurality of step pressure detection sensors arranged in the lane direction on the step board are received. May be.

  Moreover, the conditions prescribed | regulated to the foreign material adhesion pattern Di used by a foreign material determination process can also be changed suitably. For example, the number of times that the same light-shielding region La is continuously detected as a condition defined in the foreign matter adhesion pattern Di is not limited to eight.

  Further, a program for realizing the function of the detection control unit 20 in each of the above-described embodiments is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system and executed. You may perform a process by. Here, the “computer system” includes an OS and hardware such as peripheral devices. The “computer system” includes a WWW system having a homepage providing environment (or display environment). The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Further, the “computer-readable recording medium” refers to a volatile memory (RAM) in a computer system that becomes a server or a client when a program is transmitted via a network such as the Internet or a communication line such as a telephone line. In addition, those holding programs for a certain period of time are also included.

  The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line. The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

  As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the invention described in the claims and equivalents thereof, as long as they are included in the scope and gist of the invention.

DESCRIPTION OF SYMBOLS 1 Vehicle detection apparatus 10 Vehicle detection part 101 Light projection tower 102 Light reception tower S1 Light projection part S2 Light reception part 20 Detection control part 21 Light-shielding information acquisition part 22 Vehicle determination part 23 Foreign substance correspondence process part 231 Foreign substance determination part 232 Separation process part D Light-shielding Area change Dref Standard change pattern Dref1 Vehicle entry pattern Dref2 Vehicle exit pattern Dref3 Tractor passing pattern Di Foreign object adhesion pattern

Claims (10)

A plurality of light emitting units that are arranged side by side in the height direction and project light rays;
A plurality of light receiving units arranged corresponding to each of the plurality of light projecting units, and capable of receiving the light beam;
Receiving a detection signal indicating the presence or absence of light reception at the plurality of light receiving units corresponding to the light beams projected by the plurality of light projecting units, and determining whether the light beams are shielded; A light-blocking information acquisition unit that acquires a light-blocking region occupied by the light-receiving unit corresponding to the light-blocked light among the light-receiving unit;
When the shading area change indicating the temporal change of the shading area acquired by the shading information acquisition unit conforms to a standard change pattern in which a condition for the temporal change of the shading area caused by passing of the vehicle is defined. A vehicle determination unit that determines that the vehicle has passed;
With
The vehicle determination unit
Comparison between the amount of change in the number of light receiving parts belonging to the light shielding area per unit time and a first determination threshold defined in the standard change pattern, the number of light receiving parts belonging to the light shielding area, and the standard A vehicle detection device that determines whether or not the light-shielding region change matches the standard change pattern based on a comparison with a second determination threshold defined in the change pattern . The vehicle determination unit
If the light-shielding area change is one of the standard change patterns and the time-dependent change condition of the light-shielding area that occurs as the vehicle enters the vehicle conforms to the prescribed vehicle entry pattern, the vehicle has entered. Judgment,
The vehicle has exited when the change in the light-shielding area is one of the standard change patterns, and the conditions for the temporal change of the light-shielding area generated when the vehicle exits conform to the prescribed vehicle exit pattern. The vehicle detection device according to claim 1 , wherein the determination is performed. The vehicle determination unit
When the change in the light shielding area is adapted to the vehicle exit pattern, the change in the light shielding area is one of the standard change patterns and occurs with the passage of the towing vehicle over time. The vehicle detection device according to claim 2 , wherein the vehicle is determined to be a tow vehicle when the above condition is matched with a prescribed tow vehicle passing pattern. The vehicle determination unit
Whether or not the light beam belonging to the region defined in the towing vehicle passage pattern and corresponding to the connecting portion of the towing vehicle is shielded in the light shielding region change following the light shielding region change adapted to the vehicle exit pattern The vehicle detection device according to claim 3 , wherein it is determined whether or not the change in the light shielding area matches the towing vehicle passage pattern. Foreign matter adhesion in which the change in the light-shielding area does not conform to the standard change pattern, and the change in the light-shielding area is caused by the light-shielding area change being shielded by the foreign matter. A foreign matter determination unit that determines that the light beam is shielded by the foreign matter when it conforms to a pattern;
A separation processing unit for excluding, from the plurality of light receiving units, a light receiving unit corresponding to the light beam that is shielded from being detected by the light shielding information acquiring unit when it is determined that the light is blocked by a foreign object; ,
The vehicle detection device according to any one of claims 1 to 4 , further comprising: The vehicle determination unit
The light blocking area changes, based on whether the determination result to conform to any of a plurality of the standard change pattern defined by vehicle type, from claim 1, wherein the identifying the vehicle type of the vehicle according to claim 5 The vehicle detection device according to any one of claims. The vehicle determination unit
Based on the speed information indicating the traveling speed of the vehicle, any one of claims 1 to 6, wherein the light-blocking region changes and corrects whether the determination condition to conform to the standard change pattern The vehicle detection device described in 1. A vehicle using a plurality of light projecting units arranged side by side in the height direction and projecting light beams, and a plurality of light receiving units disposed corresponding to each of the plurality of light projecting units and capable of receiving the light beams A vehicle detection method for detecting the passage of
Receiving a detection signal indicating the presence or absence of light reception at the plurality of light receiving units corresponding to the light beams projected by the plurality of light projecting units, and determining whether the light beams are shielded; Obtaining a light shielding region occupied by a light receiving portion corresponding to the light ray shielded among the light receiving portions;
It is determined that the vehicle has passed when the obtained shading region change indicating the temporal change of the shading region matches a standard change pattern in which the temporal change of the shading region caused by the passage of the vehicle conforms to a prescribed standard change pattern. Steps,
Have
The step of determining that the vehicle has passed is:
Comparison between the amount of change in the number of light receiving parts belonging to the light shielding area per unit time and a first determination threshold defined in the standard change pattern, the number of light receiving parts belonging to the light shielding area, and the standard A vehicle detection method including a step of determining whether or not the change in the light shielding area matches the standard change pattern based on a comparison with a second determination threshold defined in the change pattern . A vehicle detection device comprising: a plurality of light projecting units arranged side by side in a height direction and projecting a light beam; and a plurality of light receiving units disposed corresponding to each of the plurality of light projecting units and capable of receiving the light beam Computer
Receiving a detection signal indicating the presence or absence of light reception at the plurality of light receiving units corresponding to the light beams projected by the plurality of light projecting units, and determining whether the light beams are shielded; A light-shielding information acquisition means for acquiring a light-shielding area occupied by the light-receiving part corresponding to the light-shielded light in the light-receiving part;
When the shading area change indicating the temporal change of the shading area acquired by the shading information acquisition means conforms to a standard change pattern in which the temporal change of the shading area caused by the passage of the vehicle is defined. Vehicle determination means for determining that the vehicle has passed,
Function as
The vehicle determination means includes
Comparison between the amount of change in the number of light receiving parts belonging to the light shielding area per unit time and a first determination threshold defined in the standard change pattern, the number of light receiving parts belonging to the light shielding area, and the standard A program for determining whether or not the light-shielding area change matches the standard change pattern based on a comparison with a second determination threshold defined in the change pattern .   A plurality of light emitting units that are arranged side by side in the height direction and project light rays;
  A plurality of light receiving units arranged corresponding to each of the plurality of light projecting units, and capable of receiving the light beam;
  Receiving a detection signal indicating the presence or absence of light reception at the plurality of light receiving units corresponding to the light beams projected by the plurality of light projecting units, and determining whether the light beams are shielded; A light-blocking information acquisition unit that acquires a light-blocking region occupied by the light-receiving unit corresponding to the light-blocked light among the light-receiving unit;
  When the shading area change indicating the temporal change of the shading area acquired by the shading information acquisition unit conforms to a standard change pattern in which a condition for the temporal change of the shading area caused by passing of the vehicle is defined. A vehicle determination unit that determines that the vehicle has passed;
  With
  The vehicle determination unit
  If the light-shielding area change is one of the standard change patterns and the time-dependent change condition of the light-shielding area that occurs as the vehicle enters the vehicle conforms to the prescribed vehicle entry pattern, the vehicle has entered. Judgment,
  The vehicle has exited when the change in the light-shielding area is one of the standard change patterns, and the conditions for the temporal change of the light-shielding area generated when the vehicle exits conform to the prescribed vehicle exit pattern. Judgment,
  When the change in the light shielding area is adapted to the vehicle exit pattern, the change in the light shielding area is one of the standard change patterns and occurs with the passage of the towing vehicle over time. The vehicle is determined to be a towing vehicle when the conditions of the vehicle are in conformity with the prescribed towing vehicle passing pattern.
  Vehicle detection device.

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