JP4086519B2 - Automatic fee collection system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an automatic toll collection (Electronic Toll Collection: ETC) system for toll roads. In In particular, the vehicle in the ETC lane of the tollgate can be managed accurately.
[0002]
[Prior art]
In recent years, ETC systems have been introduced on toll roads at various locations, and vehicles that can use this system can pass through toll gates on toll roads non-stop. In order to use the ETC system, an ETC vehicle-mounted device must be attached to the vehicle, an ETC card must be inserted into the vehicle-mounted device, and the vehicle must pass through the gate of an ETC lane equipped with a tollgate communication antenna. In this ETC vehicle-mounted device, information such as the vehicle type, length, width, and height of the vehicle to which it is attached is registered (setup) in advance. The ETC card is an ETC-dedicated IC card issued by a credit card company, and a pass gate ID and a fee collection record are written when the toll gate passes. Toll road tolls are set for each vehicle type. In addition, there are a distance-based system in which an entrance gate and an exit gate are provided to calculate a charge according to the travel distance, and a uniform charge system in which a fixed amount is collected at one gate. The structure of the gate differs depending on the method, the entrance gate and the exit gate, and also differs depending on the location conditions. An example of this gate is shown in FIG. 7 (perspective view) and FIG. 8 (plan view).
[0003]
This gate has an antenna 10 used for wireless communication with the ETC on-vehicle device on the lane, and the island 17 is composed of a plurality of pairs of light projectors and light receivers, and detects the passage of the vehicle by blocking light rays. The roadside which displays "passable" or "stop" for the vehicle detector S1, the second vehicle detector S2, the third vehicle detector S3 and the fourth vehicle detector S4 and the vehicle 14-1 passing through the lane When the display 11 and the vehicle 14-1 are ETC vehicles equipped with an ETC on-board device, the bar is opened, and when the vehicle 14-1 is a non-ETC vehicle, the bar is kept closed, and the ETC is mounted through the antenna 10. A lane control device 15 that includes a roadside wireless device 16 that performs wireless communication with the vehicle and controls the operation of the lane, and a booth 13 in which a receiving person enters.
[0004]
FIG. 9 is a block diagram showing the relationship between each part. The lane control device 15 identifies whether the vehicle 14-1 is an ETC vehicle or a non-ETC vehicle based on the detection information of the vehicle detectors S1 to S4 and the roadside wireless device 16, and is an ETC vehicle. Performs the necessary billing process, displays “passable” on the roadside indicator 11, and opens the circuit breaker 12. Further, when the vehicle is a non-ETC vehicle, “stop” is displayed on the roadside indicator 11, and the breaker 12 is kept closed. In the case of a non-ETC vehicle, the collector opens the circuit breaker 12 manually after collecting the fee. The lane control device 15 transmits necessary information such as billing information to the central device, and receives instruction information from the central device.
[0005]
As shown in FIG. 10, the interval between the first vehicle detector S1 and the second vehicle detector S2 is set to about 4 m. In FIG. 7, the first vehicle detector S1 is composed of two pairs of vehicle detectors, but this makes it possible to detect the traveling direction of the vehicle. Further, by identifying the vehicle as a vehicle when the light beams of both vehicle detectors are simultaneously blocked, it is possible to prevent a detection error that misidentifies newspaper or the like flying in the wind as a vehicle. However, the first vehicle detector S1 can also be composed of a pair of vehicle detectors.
[0006]
The directivity of the antenna 10 is narrowed down so that only the section between the first vehicle detector S1 and the second vehicle detector S2 is a wireless communication region. When a vehicle enters this lane and the first vehicle detector S1 detects the vehicle, the detection information is transmitted to the lane control device 15, and the lane control device 15 causes the roadside device 16 to start wireless transmission. When the vehicle is an ETC vehicle, an ETC in-vehicle device is installed on a dashboard in the vehicle. When receiving the radio signal from the antenna 10, the ETC on-vehicle device transmits vehicle information such as the vehicle type, ID information of the entrance gate written in the ETC card when passing through the entrance gate, and the like. This information is received by the antenna 10 and sent from the roadside radio device 16 to the lane control device 15.
[0007]
When there is a wireless response from the passing vehicle 14-1, the lane control device 15 executes communication processing for automatic toll collection, and when the communication processing ends normally, displays that it can pass through the roadside indicator 11. Then, open the circuit breaker 12.
When the passing vehicle 14-1 reaches the position of the second vehicle detector S2 and the second vehicle detector S2 detects the vehicle 14-1, the lane control device 15 stops transmission from the antenna 10. If the vehicle 14-1 does not respond wirelessly while traveling from the position of the first vehicle detector S1 to the position of the second vehicle detector S2, the lane control device 15 identifies the passing vehicle 14-1 as a non-ETC vehicle. Then, a stop instruction is displayed on the roadside indicator 11, and the breaker 12 is kept closed.
When the passing vehicle 14-1 reaches the position of the third vehicle detector S3 and the third vehicle detector S3 detects the vehicle 14-1, the lane control device 15 turns off the display of the roadside indicator 11. This is to prevent the following vehicle 14-2 from misrecognizing the display on the roadside indicator 11.
Further, if the ETC vehicle passes through the opened circuit breaker 12 or a non-ETC vehicle that has been charged by the toll collector passes through the breaker 12 opened by the toll collector, the fourth vehicle detector S4 Detects the stern of these vehicles and transmits them to the lane control device 15, and the lane control device 15 that receives this detects that the breaker 12 is closed.
In this way, in the ETC system, the start and end timing of road-to-vehicle communication, the lighting and extinguishing timing of the roadside indicator 11, the opening / closing timing of the circuit breaker 12, etc. are all installed on the island 17 Determined based on the detection results of S1 to S4.
[0008]
As shown in FIG. 11, each of the vehicle detectors S1 to S4 includes a plurality of projectors arranged in a row and a plurality of light receivers facing each other, and the plurality of projectors emit light to form an optical screen. When the vehicle 14 passes through the light screen, light is blocked according to the shape of the vehicle and detected by the light receiver. Japanese Patent Application Laid-Open No. 8-235487 describes that a vehicle pattern is obtained from a detection signal of the vehicle detector and used for vehicle type discrimination.
[0009]
As a vehicle detection method, a method using a distance measurement technique using laser light is also known. In this method, as shown in FIG. 12 (a), a pulse laser beam 19 is irradiated from a light projecting / receiving device 18 while being scanned to form an optical screen, and the laser beam 19 is reflected by a vehicle passing through the optical screen. The round-trip time until returning to the projector / receiver 18 is measured. This measurement data represents the cross-sectional shape of the vehicle when there is a vehicle passing through the light screen, as indicated by a black dot in FIG. Among the measurement data, the threshold value h in the height direction ₀ Measurement data exceeding the threshold w in the width direction ₀ If the measured value exceeds the value, it is determined that the vehicle is present.
[0010]
Now, the vehicle that has entered the lane passes through the lane one after another through the light screen formed by the vehicle detectors S1 to S4. Vehicles in the lane leave the lane in the order in which they entered the lane without being overtaken or overtaken.
Under these assumptions, the lane control device 15 manages the vehicle currently traveling in the lane, and when the first vehicle detector S1 detects the approaching vehicle, it assigns an ID to the vehicle. If the vehicle position is specified based on the detection signals from the second vehicle detector S2 and the third vehicle detector S3 and the fourth vehicle detector S4 detects the vehicle, the vehicle is registered. Is removed from the table as missing from the lane.
[0011]
FIG. 1 conceptually shows this vehicle management pattern. The lane control device 15 first registers the approaching vehicle detected by the first vehicle detector S1 in the table as B1, and controls the start of wireless communication. Next, when the second vehicle detector S2 detects the vehicle, the vehicle B1 is identified as having reached the position of the second vehicle detector S2, the arrival position is recorded on the table, and the road-to-vehicle communication is terminated. Then, based on the discrimination result of the ETC vehicle / non-ETC vehicle with respect to the vehicle B1, the message “passable” or “stop” is displayed on the roadside indicator 11, and the opening / closing of the circuit breaker 12 is controlled. Next, when the third vehicle detector S3 detects the vehicle, the vehicle B1 is identified as having reached the position of the third vehicle detector S3, the arrival position is recorded on the table, and the display on the roadside indicator 11 is erased. . Next, when the fourth vehicle detector S4 detects the rear of the vehicle, the vehicle B1 is identified as having passed the position of the fourth vehicle detector S4, the vehicle B1 is excluded from the management target, and the breaker 12 is closed.
[0012]
However, in the vehicle detector, there are rarely false detections that cannot be detected even though the vehicle has passed, or that the vehicle detector has detected that the vehicle has not passed. Such misdetection is detected even if one vehicle, such as a tow vehicle or trailer, is mistakenly detected as two vehicles, or a fence sticks to the vehicle detector to block the light and the vehicle passes. Caused by being unable to do so.
When erroneous detection of the vehicle detector occurs, a deviation occurs between the vehicle managed by the lane control device 15 and the vehicle existing in the lane.
For example, in FIG. 1, it is assumed that the first vehicle detector S1 detects a vehicle that has entered the lane, and the lane control device 15 registers this vehicle in the table as B2. When the second vehicle detector S2 detects the vehicle, the lane control device 15 identifies that the vehicle B2 has reached the position of the second vehicle detector S2, and records the arrival position of the vehicle B2 on the table.
[0013]
Next, when the vehicle B2 passes the position of the third vehicle detector S3, if the third vehicle detector S3 cannot detect this vehicle, the vehicle B2 is displayed on the vehicle management table as the third vehicle detector. Since the position of S3 has not been reached, the display on the roadside indicator 11 remains unerased. Even if the vehicle B2 passes through the position of the fourth vehicle detector S3 and the fourth vehicle detector S4 detects the vehicle B2, it passes through the fourth vehicle detector S4 without passing through the third vehicle detector S3. Since there is no defect, this is treated as a detection error, and the vehicle B2 remains on the vehicle management table.
Thus, a vehicle that does not actually exist in the lane but remains on the vehicle management table is called a “ghost vehicle”. Vehicle management deviation is generated by this ghost vehicle.
[0014]
The first vehicle detector S1 detects the next vehicle, and the lane control device 15 registers this vehicle as B3 in the table. When the second vehicle detector S2 detects the vehicle, the lane control device 15 identifies that the vehicle B3 has reached the position of the second vehicle detector S2, and records the arrival position of the vehicle B3 on the table.
Next, when the vehicle B3 passes the position of the third vehicle detector S3 and the third vehicle detector S3 detects this vehicle, the lane control device 15 actually passes the vehicle B3, The ghost vehicle B2 is identified as having reached the position of the third vehicle detector S3, the arrival position of the vehicle B2 is recorded on the table, and the display on the roadside indicator 11 is erased. Here, vehicle management deviation occurs.
[0015]
Next, when the vehicle B3 passes the position of the fourth vehicle detector S4 and the fourth vehicle detector S4 detects this vehicle, the lane control device 15 similarly determines that the ghost vehicle B2 is the fourth vehicle detector S4. The vehicle B2 is identified as having passed the position, and the vehicle B2 is excluded from the management target. Therefore, this time, the vehicle B3 remains in the vehicle management table as a ghost vehicle. Thus, once a ghost vehicle is generated, the ghost vehicle is updated one after another, and the vehicle management deviation continues.
[0016]
When this vehicle management misalignment occurs, a message displayed based on the identification result of the ETC vehicle / non-ETC vehicle with respect to the preceding vehicle is displayed on the roadside indicator 11 until the next vehicle passes, It will confuse the driver.
An attendant (accounter) can know the existence of a ghost vehicle for the first time when a vehicle record is left on the vehicle management table when no vehicle is traveling on the lane by looking at the lane. it can. At this time, the clerk performs a manual operation to eliminate the ghost vehicle and corrects the vehicle management deviation.
[0017]
Japanese Patent Laid-Open No. 2001-312753 discloses an ETC system that enables automatic detection of this vehicle management deviation. In this system, a two-antenna type gate (in addition to the first antenna 10 of the gate in FIG. 7, a second antenna is provided behind the circuit breaker 12. The first antenna receives the OBE information received from the ETC OBE, the second antenna checks the OBE information received from the ETC OBE, and checks the vehicle management deviation. If there is an abnormality, change the management content.
In addition, the one-antenna type gate measures the staying time of the vehicle in the lane, displays an error display on the operation panel when a certain time is exceeded, and a staff member who sees the error manually corrects the vehicle management deviation. To do.
[0018]
[Problems to be solved by the invention]
However, in the vehicle management method disclosed in Japanese Patent Application Laid-Open No. 2001-312753, in the case of the single antenna system, the reliability of the detection result of the vehicle management shift is poor, and therefore the vehicle management shift is automatically detected using this detection result. There is a problem that it cannot be corrected automatically.
In the case of the two-antenna method, there is a problem that when a non-ETC vehicle enters the lane, the vehicle management deviation cannot be checked.
[0019]
The present invention solves such conventional problems, and an ETC system capable of detecting a vehicle management shift due to a false detection of a vehicle detector and returning to a correct vehicle management state in any type of lane. Provide Do The purpose is that.
[0020]
[Means for Solving the Problems]
Therefore, in the ETC system of the present invention, By many optical axes arranged in a straight line light of Vehicle that forms a screen and passes through the screen The light shielding optical axis that is shielded by A plurality of vehicle detection means arranged at intervals along the same lane, and detecting and generating data representing the characteristics of the vehicle based on the detection results; and each of the vehicle detection means Using the output data , The vehicle detection means Vehicle It has passed When Change point of the number of light-blocking optical axes of Vehicle management means for identifying the identity of the vehicle from the number and specifying the position of the vehicle passing through the lane is provided.
[0022]
In this way, in the present invention, the vehicle detector outputs not only the output of the on / off signal but also the data that allows the passing vehicle to be specified, so that the vehicle that passes through each vehicle detector using this data. It is possible to check the identity of the vehicle, and the vehicle management deviation can be corrected by this check.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
The hardware configuration of the ETC system in the embodiment of the present invention is the same as that shown in FIGS.
In this system, when the vehicle passes through the light screens of the vehicle detectors S1 to S4, features (parameters) for identifying the vehicle are extracted from the detection information. And using this parameter, the identity of the vehicle which passes each vehicle detector is checked, and vehicle management gap is corrected.
[0024]
FIGS. 4A, 4B, and 4C schematically show the relationship between a vehicle detector that forms an optical screen and a vehicle that has a different loading form. The vehicle detector, like the existing one, has a height of about 160 cm, has approximately 50 optical axes, the projector emits light every few ms, and the light is detected by the light receiver.
The vehicle detector of this embodiment stores a light-shielded optical axis and a light-shielded optical axis every time a light projecting / receiving (scanning) is performed on a passing vehicle at intervals of several ms, and vehicle detection is performed based on these. The parameters of the vehicle passing through the vessel are calculated.
Incidentally, FIG. 3 shows a vehicle shape obtained by scanning a vehicle passing through the vehicle detector at intervals of several ms, storing the light-shielded optical axis and the light-shielded optical axis, and combining them based on them. Yes. In this way, a light-shielded optical axis and a light-shielded optical axis can be clearly distinguished.
[0025]
The following three types of parameters are calculated.
(1) Parameter 1 (maximum vehicle height optical axis)
Numbers from 1 to 50 are assigned to the optical axes in order from the bottom, and the highest optical axis shielded when the vehicle passes the vehicle detector is obtained as parameter 1 (maximum vehicle height optical axis) of the vehicle. As shown in FIGS. 4A and 4B, the maximum vehicle height optical axis is 50 in a vehicle in which the height of the load or the vehicle body is higher than the height of the vehicle detector. This parameter 1 does not change even when the vehicle speed changes in the lane. Therefore, the vehicle traveling on the lane in the form of FIGS. 4A and 4B and the vehicle traveling on the lane in the form of FIG.
[0026]
(2) Parameter 2 (average shading rate)
When the vehicle passes through the vehicle detector, a ratio between the average value of the number of optical axes shielded by the vehicle in one scan and the maximum vehicle height optical axis (parameter 1) is calculated as parameter 2 (average light shielding rate). . If the vehicle speed is constant, this average light shielding rate represents the ratio of the area of the vehicle portion to the region including the vehicle portion and the shaded portion in FIG. 4C.
This average light shielding rate is calculated as follows.
The number of light axes shielded by each scan performed while the vehicle passes the vehicle detector is cumulatively added to obtain the cumulative number of light shields. Next, the number of light shielding cumulative optical axes is divided by the number of scans, and the average number of light shielding axes is calculated by the following equation (1).
Average number of light-shielding axes = number of light-shielded cumulative optical axes / number of scans (1)
Next, an average shading rate is calculated by the following equation (2).
Average shading rate = Average number of shading axes / Maximum vehicle height optical axis (2)
The maximum vehicle height optical axis is the value of parameter 1, and as shown in FIGS. 4 (a) and 4 (b), the vehicle height is 50 for vehicles having a vehicle height higher than the vehicle detector.
This average shading rate is a value specific to the vehicle unless the speed is changed in the process of passing the vehicle detector. Therefore, the vehicle in the form of FIG. 4A and the vehicle in the form of FIG.
[0027]
However, when the vehicle speed changes in the process of passing through the vehicle detector, for example, in FIG. 4B, when the passing speed of the head portion of the vehicle is slow and the passing speed of the luggage portion is fast, the light shielding optical axis Since the number of scans at the top part with a small number increases, and the number of scans at the luggage part with a large number of light-shielding optical axes decreases, the average light shielding rate decreases, and conversely, the passing speed of the head part of the vehicle is high, When the passing speed of the luggage portion is slow, the average light shielding rate increases.
[0028]
(3) Parameter 3 (normalized shading rate)
A point (change point) where the light-shielding optical axis position changes while the vehicle passes the vehicle detector is obtained, and an average light-shielding rate is calculated only for the change point, and this is set as parameter 3 (normalized light-shielding rate). To do. 4 (a), 4 (b), and 4 (c), the changing points of the vehicles of the respective forms are shown below the vehicles. Even if the vehicle speed changes in the process of passing through the vehicle detector, the number of change points remains unchanged, and the number of light-shielding optical axes at the change points does not depend on the vehicle speed. Therefore, by calculating the average light blocking rate only for the change point, a vehicle specific light blocking rate that is not affected by the vehicle speed can be obtained.
[0029]
This normalized shading rate is calculated as follows.
Scan the vehicle passing the vehicle detector, compare the number of light-shielded optical axes with the number of light-shielded optical axes in the previous scan, and if not, cumulatively add the number of light-shielded optical axes. Do not add. In this way, the cumulative number of light-shielded light axes at the change point (the number of cumulative light-shielded light axes) is obtained. Next, the number of changed light-shielding cumulative optical axes is divided by the number of change points, and the normalized number of light-shielding axes corresponding to the average number of light-shielding axes is calculated by the following equation (3).
Normalized number of shading axes = Number of accumulated cumulative shading optical axes / number of changing points (3)
Next, the normalized shading rate is calculated by the following equation (4).
Normalized shading rate = normalized shading axis number / maximum vehicle height optical axis (4)
By using this parameter 3 (normalized shading rate), it is possible to distinguish between the vehicle in the form of FIG. 4 (a) and the vehicle in the form of FIG. 4 (b) even when the vehicle speed changes.
The vehicle detectors S1, S2, S3, and S4 that have calculated these parameters output the parameters to the lane control device 15.
[0030]
The flowchart of FIG. 2 shows the processing procedure of the vehicle detectors S1, S2, S3, and S4.
When light-blocking of the optical axis is detected during scanning (step 1), the number of scans is incremented by 1, an optical axis pattern indicating the position of the light-blocking optical axis is stored (step 2), and the maximum vehicle height optical axis is updated. Whether or not is identified (step 3). When the maximum vehicle height optical axis is updated, the optical axis position number is stored (step 4).
Next, the number of light-shielding optical axes is added to the number of light-shielded cumulative optical axes (step 5), and it is identified whether or not the optical axis pattern has changed from the optical axis pattern at the previous scan (step 6). When the optical axis pattern is changing, the number of light-shielding optical axes is added to the number of light-shielding cumulative optical axes (step 7), and the number of change points is incremented by 1 (step 8). This process is repeated while light-blocking of the optical axis is detected.
[0031]
When the detection of the light shielding optical axis is completed in step 1, it is identified whether or not the detected one is a vehicle (step 9). When the vehicle is a vehicle, the average number of light-shielding axes is calculated by equation (1) using the number of scans obtained in step 2 and the cumulative number of light-shielding axes obtained in step 5 (step 10). Using the number of axes and the number of the maximum vehicle height optical axis obtained in step 4, the average light shielding rate is calculated by equation (2) (step 11). Also, using the number of change points obtained in step 8 and the change light shielding cumulative optical axis number obtained in step 7, the normalized light shielding axis number is calculated by equation (3) (step 12), and the calculated normalized light shielding axis is calculated. Using the number and the number of the maximum vehicle height optical axis obtained in step 4, the normalized shading rate is calculated by equation (4) (step 13). Then, the obtained maximum vehicle height optical axis number (parameter 1), average shading rate (parameter 2) and normalized shading rate (parameter 3) are transmitted to the lane control device 15 (step 14).
[0032]
The lane control device 15 that has received the values of each parameter from the vehicle detectors S1, S2, S3, S4 uses these parameters to check the identity of the vehicle passing through each vehicle detector and Correct it.
For example, in FIG. 1, when the first vehicle detector S1 that detects a vehicle transmits a parameter value p2 to the lane control device 15, the lane control device 15 sets this vehicle as B2 and registers it in the vehicle management table together with the parameter p2. To do. When the second vehicle detector S2 detects the vehicle and transmits the parameter value p2 to the lane control device 15, the lane control device 15 confirms the identity of the parameter p2, and the vehicle B2 is the second vehicle detector S2. The arrival position of the vehicle B2 is recorded in the vehicle management table by identifying that the position has been reached.
[0033]
It is assumed that the third vehicle detector S3 cannot detect the passage of the vehicle B2.
When the first vehicle detector S1 that detects the next vehicle transmits the parameter value p3 to the lane control device 15, the lane control device 15 sets this vehicle to B3 and registers it in the vehicle management table together with the parameter p3. When the second vehicle detector S2 detects the vehicle and transmits the parameter value p3 to the lane control device 15, the lane control device 15 confirms the identity of the parameter p3, and the vehicle B3 is the second vehicle detector S2. The arrival position of the vehicle B3 is recorded in the vehicle management table by identifying that the position has been reached.
[0034]
When the third vehicle detector S3 detects the vehicle B3 and transmits the parameter value p3 to the lane control device 15, the lane control device 15 receives the parameter p2 of the vehicle B2 to be detected by the third vehicle detector S3, and receives the parameter p2. Is compared with the determined parameter p3 to identify that they are inconsistent. At this time, the lane control device 15 shifts to a mode for correcting vehicle management based on the next approaching vehicle.
[0035]
When the first vehicle detector S1 that detects the next vehicle transmits to the parameter value p4, the lane control device 15 sets this vehicle to B4 and registers it in the vehicle management table together with the parameter p4. When the second vehicle detector S2 detects the vehicle and transmits the parameter value p4 to the lane control device 15, the lane control device 15 confirms the identity of the parameter p4, and the vehicle B4 is the second vehicle detector S2. The arrival position of the vehicle B4 is recorded in the vehicle management table by identifying that the position has been reached.
[0036]
When the third vehicle detector S3 detects the vehicle B4 and transmits the parameter p4 to the lane control device 15, the lane control device 15 uses this parameter p4 as the parameter p3 of the vehicle B3 that the third vehicle detector S3 should detect. , And compared with the parameter p4 received from the second vehicle detector S2, the vehicle that has reached the position of the third vehicle detector S3 is identified as the vehicle B4. Thus, the lane control device 15 corrects the data in the vehicle management table so that the vehicle B4 is not a ghost vehicle.
In this way, the lane control device 15 can specify the vehicle using the parameters detected by each vehicle detector and correct the vehicle management deviation.
[0037]
Note that the number of change points obtained in step 8 of FIG. 2 may be used as one of parameters for specifying the vehicle. Alternatively, the vehicle may be specified by using only parameter 1 and parameter 2, or parameter 1 and parameter 3.
It is also possible to use only one parameter for vehicle identification. However, if the number of parameters is small, the reliability of the determination result as to whether or not the vehicle is the same decreases. In this case, the reliability of the determination result can be improved by group management that compares not only the parameters of the target vehicle but also the parameters of a plurality of vehicles including the target vehicle.
[0038]
FIG. 5 schematically shows an example of vehicle management by group management.
Here, vehicle group management using only the maximum vehicle height optical axis as a parameter and using the parameter difference between the preceding vehicle and the following vehicle will be described.
It is assumed that the vehicle type of the passing vehicle and the maximum vehicle height optical axis are as follows.
Vehicle B1 ... Mini vehicle (maximum vehicle height optical axis = 30)
Vehicle B2 ... Private vehicle (maximum vehicle height optical axis = 40)
Vehicle B3 ... light truck (maximum vehicle height optical axis = 49)
Vehicle B4 ... large truck (maximum vehicle height optical axis = 50, vehicle height far exceeds the height of the vehicle detector)
Vehicle B5 ... Private car (maximum vehicle height optical axis = 40)
The vehicle detectors S1, S2, S3, and S4 that detect the vehicle detect the maximum vehicle height optical axis and output the value to the lane control device 15 as vehicle height information.
[0039]
Further, it is assumed that there is a slight shift in the optical axis position of the vehicle detector, and this deviation is as follows.
Vehicle detector S1 standard 0
Vehicle detector S2 -1
Vehicle detector S3 +1
Vehicle detector S4 0
In FIG. 5, the maximum vehicle height optical axis of the vehicle detected by each vehicle detector is written in the figure of each vehicle.
[0040]
When the first vehicle B1 passes through the lane, the maximum vehicle height optical axis detected by the vehicle detectors S1, S2, S3, and S4 is recorded in the vehicle management table.
The vehicle detectors S1 and S2 that have detected the second vehicle B2 output vehicle height information (40) and (39), respectively. Receiving this, the lane control device 15 calculates the difference of the maximum vehicle height optical axis from the preceding vehicle B1.
Difference calculated from vehicle height information of vehicle detector S1 40-30 = 10
The difference calculated from the vehicle height information of the vehicle detector S2 39−29 = 10
Since these differences are considered to be within the range of identity, the lane control device 15 determines that there is no abnormality in vehicle management.
The vehicle detector S3 that made the detection error does not report vehicle height information.
[0041]
The vehicle detector S4 outputs vehicle height information (40), but the lane control device 15 discards the vehicle height information. As a result, the vehicle management table records that the vehicle stays between the vehicle detector S2 and the vehicle detector S3.
The vehicle detectors S1, S2, S3, and S4 that have detected the third vehicle B3 output vehicle height information (49), (48), (50), and (49), respectively.
[0042]
The lane control device 15 assigns the vehicle height information received from the vehicle detectors S3 and S4 as vehicle height information of the second vehicle B2, and calculates the difference of the maximum vehicle height optical axis from the preceding vehicle B1 as follows. .
Difference calculated from vehicle height information of vehicle detector S3 50−31 = 19
Difference calculated from vehicle height information of vehicle detector S4 49-30 = 19
These values are compared with the difference 10 calculated from the vehicle height information of the vehicle detectors S1 and S2 that detected the second vehicle B2. As a result, these values are out of the range of identity (the error of the maximum vehicle height optical axis should be within ± 1), so the vehicle passing through the vehicle detectors S1, S2 and the vehicle detector S3, It is determined that the vehicle that has passed S4 is different, and the staying vehicle recorded in the vehicle management table at this time is deleted from the vehicle management data as a vehicle management deviation target vehicle.
After clearing the vehicle management data in this way, the vehicle management is resumed from the next vehicle (and hence from the vehicle B4).
[0043]
Since there is no comparison target for the first vehicle B4 after the restart, the maximum vehicle height optical axis detected by the vehicle detectors S1, S2, S3, and S4 is stored in the vehicle management table in the same manner as at the start. Record. In this case, in combination with the vehicle management method described in FIG. 1 for checking the identity of vehicles passing through each vehicle detector using parameters, the vehicle management method checks the flow of a certain number of times. After confirming that there is no management deviation, the group management using the difference may be performed.
[0044]
Although the case where the vehicle group management is performed using one parameter is shown here, it is of course possible to use a plurality of parameters.
Further, in this embodiment, the case where the vehicle detector calculates the average shading rate and the normalized shading rate and outputs it to the lane control device has been shown. However, the vehicle detector can perform steps 1 to 8 in FIG. The number of scans obtained in step 2, the maximum vehicle height optical axis obtained in step 4, the cumulative number of light shields obtained in step 5, the cumulative number of light shields obtained in step 7, and in step 8 The obtained number of change points may be transmitted to the lane control device 15, and the lane control device 15 may calculate the average shading rate and the normalized shading rate using these data.
[0045]
In addition, here, when the vehicle detector S3 does not detect the vehicle, even if the vehicle detector S4 that detects the vehicle outputs the parameter information, the parameter information is discarded. Record the parameter information output from the vehicle detector S4, identify whether it matches the parameter information output from the vehicle detector S1 or S2, and determine whether there is an abnormality in the vehicle detector S3. May be. When the same parameter information is output from the vehicle detectors S1, S2 and S4, but the parameter information is not output from the vehicle detector S3, or when the situation occurs once or several times in succession, It is possible to determine that an abnormality has occurred in the vehicle detector S3 and take measures such as issuing a warning to the administrator.
[0046]
Further, here, a case has been described in which a vehicle detector having a structure in which a plurality of light projectors and light receivers shown in FIG. 11 are arranged in a row is used as the vehicle detector. However, the pulse laser light shown in FIG. It is also possible to use a vehicle detector that detects the vehicle.
In addition, as shown in FIG. 6, an imaging element (camera) 20 is arranged in place of one or a plurality of projectors or light receivers arranged in a row of vehicle detectors (or separately from the projectors and light receivers). The color of the vehicle detected by the element 20 may be added to the parameter. In this way, even vehicles having the same shape can be distinguished by the color of the vehicle body, and the identification ability for the vehicle is improved.
[0047]
【The invention's effect】
As is clear from the above description, the ETC system of the present invention. Then Since the vehicle detector outputs data that allows the passing vehicle to be identified, this data can be used to check the identity of the vehicle passing through each vehicle detector and correct the vehicle management deviation. The operation of the vehicle detector can be performed only by changing the software of the vehicle detector. Therefore, the present invention is highly practical because the hardware of the existing ETC system can be used as it is in the implementation.
[0048]
In the present invention, even when a non-ETC vehicle travels on a lane, the vehicle management can be performed accurately.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining vehicle management in an ETC system according to an embodiment of the present invention;
FIG. 2 is a flowchart showing a processing procedure of the vehicle detector in the embodiment of the present invention;
FIG. 3 is a diagram showing a vehicle shape reproduced from the detection result of the vehicle detector in the embodiment of the present invention;
FIG. 4 is an explanatory diagram showing a relationship between a vehicle shape and a vehicle detector for explaining an embodiment of the present invention;
FIG. 5 is a diagram for explaining vehicle group management in the ETC system according to the embodiment of the present invention;
FIG. 6 is a view showing an example of a vehicle detector in the embodiment of the present invention;
FIG. 7 is a perspective view showing a toll gate of a conventional ETC system;
FIG. 8 is a plan view showing a toll gate of a conventional ETC system;
FIG. 9 is a functional block diagram showing the configuration of a toll gate of a conventional ETC system;
FIG. 10 is a diagram showing a road-to-vehicle communication area of a conventional ETC system;
FIG. 11 is a view showing a light screen of a conventional vehicle detector,
FIG. 12 is a diagram showing a conventional vehicle detector using laser light.
[Explanation of symbols]
S1 First vehicle detector
S2 Second vehicle detector
S3 Third vehicle detector
S4 4th vehicle detector
10 Antenna
11 Roadside indicator
12 Circuit breaker
13 booth
14-1, 14-2 Vehicle
15 Lane control device
16 Roadside radio equipment
17 Island
18 Emitter / receiver
19 Pulsed laser beam
20 Image sensor

Claims (3)

Forming a screen of light to detect the light shielding beams blocked by the vehicle passing through the screen by a number of optical axis aligned in a straight line, and generates data representing a characteristic of the vehicle based on the detection result Outputting a plurality of vehicle detection means arranged at intervals along the same lane;
By using the data output from each of the vehicle detection means, the vehicle detection means to identify the identity of the number of changing points of the light blocking optical number of axes of the vehicle when the vehicle passes, passing through the said lane An automatic toll collection system comprising vehicle management means for specifying the position of the vehicle.   The vehicle management means includes a plurality of the following vehicle detection means when the data is output from the subsequent vehicle detection means arranged behind the vehicle detection means of interest and the data is not output from the vehicle detection means of interest. The automatic detection according to claim 1, wherein the identity of the data output from each of the vehicle detection means is determined, and the presence or absence of abnormality of the vehicle detection means of interest is identified based on the determination result. Toll collection system. The automatic fee collection system according to claim 2 , wherein the vehicle management means outputs a warning when the vehicle detection means identifies that the vehicle detection means is abnormal.

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