JP2020087282A - Vehicle detection device and vehicle detection method - Google Patents

Abstract

To provide a vehicle detection device having excellent construction easiness and detection accuracy.SOLUTION: A vehicle detection device according to an embodiment comprises a rangefinder and a determination unit. The rangefinder scans a laser light radially along a virtual plane that intersects with a traveling direction of a vehicle on a lane and is perpendicular to the lane, and measures a distance value to an object according to a scanning angle of the laser light based on a detection result of the reflected light of the laser light radially scanned. The determination unit executes a first object detection for detecting a presence/absence of the object from an object detection distance threshold for each scanning angle included in a first vehicle determination table, and the distance value to the object according to the scanning angle of the laser light. Further, the determination unit executes a second object detection for detecting an object having a predetermined size or more from a first object detection number threshold included in the first vehicle determination table, and a number of detected distance values to the object according to the scanning angle of the laser light. Furthermore, the determination unit executes a first vehicle determination process of determining the presence/absence of the vehicle based on the first object detection and second object detection.SELECTED DRAWING: Figure 4

Description

Embodiments of the present invention relate to a vehicle detection device and a vehicle detection method.

The ETC system (Electronic Toll Collection System), which is widely used on toll roads, allows vehicles to be installed at the tollgate by wireless communication between the on-board device of the vehicle that travels in the lane of the tollgate and the lane equipment provided at the tollgate. Realize non-stop charge collection without stopping. In the ETC system, when a vehicle passes through a toll gate, the vehicle position is detected by a vehicle detector and various processes are executed at appropriate timing.

The ETC system employs vehicle sensors of various sensor types. For example, a transmission line sensor type vehicle detector using infrared light is often used. In the transmissive line sensor system, a light projector and a light receiver are installed on one side of a lane on which a vehicle runs and on the opposite side. The light projector has a light emitting unit and has a function of irradiating light, and the light receiver has a light receiving element which receives the irradiation light of the light projector and converts it into an electric signal. The light emitter and the light receiver have optical axes arranged in a line in the height direction from a position approximately 200 mm from the road surface. When a vehicle passes between a light emitter and a light receiver that are installed so as to face each other across a lane, the transmitted light is blocked and the electrical characteristics of the light receiving element change, so that it is determined that the vehicle is detected.

JP, 10-105867, A JP, 2007-157066, A JP, 2014-167824, A JP2012-128561A

In the above-described transmission line sensor type vehicle detector, the light projector and the light receiver are installed so as to face each other with the lane in between, and therefore a space for installation on both shoulders is required. In addition, it is necessary to connect these projector and receiver with a cable. Further, the sensor (optical axis) arranged at a position close to the road surface is easily affected by deposits such as mud or dust. That is, there is a possibility that a deposit such as dust much smaller than the vehicle is erroneously detected as the vehicle.

An object of the present invention is to provide a vehicle detection device that is excellent in ease of construction and detection accuracy. Another object of the present invention is to provide a vehicle detection method with excellent detection accuracy.

The vehicle detection device according to the embodiment includes a rangefinder and a determination unit. The rangefinder scans the laser beam radially along a virtual plane that intersects the traveling direction of the vehicle on the lane and is perpendicular to the lane, and the laser beam is based on the detection result of the reflected light of the laser beam scanned radially. The distance value to the object is measured according to the scanning angle of. The determination unit detects the presence or absence of an object based on the object detection distance threshold for each scanning angle included in the first vehicle determination table and the distance value to the object according to the scanning angle of the laser beam. Run. In addition, the determination unit detects an object having a predetermined size or more from the first object detection number threshold included in the first vehicle determination table and the detection number of the distance value to the object according to the scanning angle of the laser light. The second object detection is performed. Furthermore, the determination unit executes a first vehicle determination process of determining the presence/absence of the vehicle based on the first and second object detections.

FIG. 1 is a diagram showing an example of a schematic configuration of an ETC system according to an embodiment. FIG. 2 is a top view and a side view showing an installation example of a lane device of the ETC fee collection system according to the embodiment in a lane. FIG. 3 is a block diagram showing an example of a schematic configuration of a lane device of the ETC fee collection system according to the embodiment. FIG. 4 is a block diagram showing an example of a schematic configuration of the vehicle detector according to the embodiment. FIG. 5: is a figure which shows an example of schematic structure of the laser range finder of the vehicle detector which concerns on embodiment. FIG. 6 is a diagram showing an example of installation of a vehicle detector and scanning by a laser range finder. FIG. 7A is a diagram for explaining a first vehicle determination logic (first vehicle determination process) by the vehicle detector according to the embodiment. FIG. 7B is a first vehicle detection including an object detection distance threshold T1 for detecting the presence or absence of an object (non-fixed object) by the first object detection of the first vehicle determination logic by the vehicle detector according to the embodiment. It is a figure which shows an example of a table. FIG. 7C is a first object detection number for each divided area for detecting an object (non-fixed object) having a predetermined size or more by the second object detection of the first vehicle determination logic by the vehicle detector according to the embodiment. It is a figure which shows an example of a threshold value. FIG. 8A is a diagram for explaining a second vehicle determination logic (second vehicle determination process) by the vehicle detector according to the embodiment. FIG. 8B is a second vehicle including a fixed object detection distance threshold T2 for detecting the presence or absence of an object (non-fixed object) by the third object detection of the second vehicle determination logic by the vehicle detector according to the embodiment. It is a figure which shows an example of a detection table. FIG. 8C is a second object detection number threshold for each area for detecting an object (non-fixed object) having a predetermined size or more by the fourth object detection of the second vehicle determination logic by the vehicle detector according to the embodiment. It is a figure which shows an example. FIG. 9 is an example of a process of determining the presence or absence of a vehicle based on a first vehicle determination logic including first and second object detections and a second vehicle determination logic including third and fourth object detections. It is a flowchart shown.

Hereinafter, an example of the ETC system according to the embodiment will be described with reference to the drawings.
FIG. 1 is a diagram showing an example of a schematic configuration of an ETC system according to an embodiment.
As shown in FIG. 1, the ETC system includes a central unit 1, a tollgate server 2 and a lane server 3 in each tollgate, and a lane device 4 in each lane of the tollgate. The lane equipment 4 is installed along the lane of each tollgate.

The central device 1 is connected to a tollgate server 2 installed at each tollgate. The toll gate server 2 at the predetermined toll gate is connected to the lane server 3 at the same toll gate. The central device 1 exchanges various information with the tollgate server 2 of each tollgate, and the tollgate server 2 exchanges various information with the lane server 3. For example, the central unit 1 sends the toll table to the tollgate server 2, and the tollgate server 2 sends the toll table to the lane server 3. The toll table includes toll charges for each vehicle type for each section of the tollgate. The lane server 3 controls the lane device 4 based on sensor data or the like transmitted from the lane device 4. Note that the sensor data includes detection of a passing vehicle (vehicle presence/absence).

The vehicle 5 that uses the ETC fee collection system is provided with the vehicle-mounted device 51, and the ETC card 52 is inserted into the vehicle-mounted device 51. The vehicle-mounted device 51 stores the vehicle-mounted device specific information. The ETC card 52 stores card information including card-specific information. The vehicle-mounted device 51 receives the entry record through communication with the lane device 4 when the entrance toll gate is passing, and writes the entry record in the ETC card 52. The entrance record, which is one of the travel history information, includes toll gate identification information indicating the entrance toll gate and entrance date and time information (communication date and time information at the time of entrance).

The lane device 4 wirelessly communicates with the vehicle-mounted device 51 of the vehicle entering the lane of the exit toll gate, and the lane device 4 receives the vehicle-mounted device specific information, the card information, the entrance record, etc. transmitted from the vehicle-mounted device 51. To do. Further, the lane device 4 transmits the received information to the lane server 3 and also the entry record received from the lane server 3 to the vehicle-mounted device 51. The vehicle-mounted device 51 receives the entry record through communication with the lane device 4 when passing through the exit toll gate, and writes the entry record in the ETC card 52.

The lane server 3 generates a departure record, which is one of the traffic history information, and the entry record includes toll gate identification information indicating the exit toll gate where the lane server 3 is installed, departure date/time information (communication date/time information at the time of entry) ), and tolls. The lane server 3 refers to the toll table received in advance and calculates the toll based on the toll gate identification information indicating the entrance toll gate, the entry date and time information, the toll gate identification information indicating the exit toll gate, and the exit date and time information. .. Further, the lane server 3 transmits the usage statement including the vehicle-mounted device specific information, the card information, the entry record, and the entry record to the tollgate server 2. The toll booth server 2 receives the usage statement and sends the usage statement to the central device 1.
Hereinafter, the information read from the ETC card 52 by the vehicle-mounted device 51 is referred to as card read information. The card reading information includes card information, traffic history information, and the like.

Next, with reference to FIGS. 2 and 3, the lane device that communicates with the vehicle-mounted device of the vehicle passing through the tollgate will be described in detail.
FIG. 2 is a top view and a side view showing an installation example of a lane device of the ETC fee collection system according to the embodiment in a lane.

As shown in FIG. 2, islands 40 extending along the lane 49 are arranged opposite to each other on both sides of the lane 49 on which the vehicle travels. The vehicle travels in the lane 49 between these two islands 40 from upstream to downstream. In the island 40, the first vehicle detector S1, the second vehicle detector S2, the interface concentrator 41, the booth 48, the roadside indicator 42, and the start controller are arranged in this order from upstream to downstream of the lane 49. 44, a third vehicle detector S4, a lane monitoring camera 45, and the like are provided. The booth 48 includes a clerk 43 for the staff. Further, on the lane 49, a first antenna 46 and a second antenna 47 are provided in this order from upstream to downstream of the lane 49.

FIG. 3 is a block diagram showing an example of a schematic configuration of a lane device of the ETC fee collection system according to the embodiment.
As shown in FIG. 3, the lane device 4 includes an interface aggregation unit 41, a roadside display 42, a fare collector 43, a start controller 44, a lane monitoring camera 45, a first vehicle detector S1, and a second vehicle detector. S2, a vehicle detector S4, a first antenna 46, and a second antenna 47 are provided.

Each part of the lane equipment will be described in detail with reference to FIGS. 2 and 3.
One island 40 is provided with a first vehicle detector S1, a second vehicle detector S2, and a vehicle detector S4 in order from upstream to downstream. The first vehicle detector S1 detects a vehicle that reaches a first point on the lane 49, and the second vehicle detector S2 detects a vehicle that reaches a second point downstream from the first point. Then, the third vehicle detector S4 detects a vehicle that reaches a third point downstream of the second point. For example, the first vehicle detector S1 or the like emits laser light, detects reflected light of laser light reflected by an object such as a vehicle, and detects the object based on the time from the irradiation of laser light to the detection of reflected light. The distance value up to is measured, and the presence or absence of the vehicle is determined based on the measurement result of the distance value. The first vehicle detector S1 or the like outputs a vehicle detection signal ON corresponding to the determination of the presence of the vehicle or a vehicle detection signal OFF corresponding to the determination of the absence of the vehicle by the operation control/vehicle determination unit to the interface aggregation unit 401. To do. Details of the presence/absence determination of the vehicle by the first vehicle detector S1 and the like will be described later in detail.

The interface aggregating unit 41 aggregates information from each unit and outputs the information to the lane server 3. Further, the interface aggregation unit 41 outputs information from the lane server 3 to each unit. For example, the interface aggregating unit 41 outputs the vehicle detection signal ON or OFF to the lane server 3. The lane server 3 detects the position (movement) of the vehicle on the lane 49 based on the vehicle detection signal ON or OFF from the first vehicle detector S1, the second vehicle detector S2, and the vehicle detector S4. , Controls the operation of the lane equipment 4.

Further, two antenna installation gates are provided on the two islands 40 in order from the upstream side to the downstream side across the lane 49. A first antenna 46 is provided on the first antenna installation gate. A second antenna 47 is provided on the second antenna installation gate. The first antenna 46 and the second antenna 47 communicate with the vehicle-mounted device 51 of the vehicle 5, receive various information transmitted from the vehicle-mounted device 51, and transmit various information to the vehicle-mounted device 51. ..

In the lane device 4 at the entrance toll gate, the first antenna 46 and the second antenna 47 transmit the entry record to the vehicle-mounted device 51 and receive the vehicle-mounted device specific information and the card information transmitted from the vehicle-mounted device 51. Then, the received information is transmitted to the interface aggregation unit 41. Further, in the lane device 4 at the exit toll gate, the first antenna 46 and the second antenna 47 receive the vehicle-mounted device specific information, the card information, the entry record, etc. transmitted from the vehicle-mounted device 51, and are mounted on the vehicle. The participation record and the like are transmitted to the device 51. Further, the first antenna 46 and the second antenna 47 transmit the information received from the vehicle-mounted device 51 to the interface aggregation unit 41.

The interface aggregating unit 41 transmits the vehicle-mounted device specific information, the card information, the entry record, and the like to the lane server 3. The interface aggregation unit 41 also transmits various information from the lane server 3 to the first antenna 46 and the second antenna 47. In addition, the interface aggregation unit 41 outputs the toll notified from the lane server 3 to the roadside display 42 and the collection machine 43.

The roadside display 42 displays the toll charge output from the interface aggregation unit 41 to the driver of the vehicle. The booth 48 on which the toll collector waits is provided with a toll collection machine 43, and the toll collection machine 43 also displays the toll charge output from the interface aggregation section 41. The toll collector can receive the cash from the user who desires the cash settlement, and can execute the settlement processing at the collection machine 43. In the case where the cash collection is executed by cash, the collection machine 43 notifies the central apparatus 1 of the payment completion information indicating that the payment is completed by cash via the interface consolidating unit 41, the lane server 3, and the tollgate server 2.

The start controller 44 controls opening/closing of the start control bar based on the start control information (passing permission or temporary stop) from the interface aggregation unit 41. The start control bar physically blocks passage of the vehicle (exit from the toll gate) in the closed state, and permits the passage of the vehicle in the opened state. Based on the passage permission from the interface aggregation unit 41, the start controller 44 raises the start control bar from the state of the passage control bar blocking the passage to permit passage, and based on the temporary stop from the interface aggregation unit 41, the start control is performed. Keep the bar blocked to prevent traffic. The lane monitoring camera 45 photographs the vehicle when the vehicle enters or leaves the lane 49.

Next, the first vehicle detector S1, the second vehicle detector S2, and the third vehicle detector S4 will be described with reference to FIGS. 4 and 5. Hereinafter, the first vehicle detector S1, the second vehicle detector S2, and the third vehicle detector S4 are referred to as the first vehicle detector S1 and the like.
FIG. 4 is a block diagram showing an example of a schematic configuration of the vehicle detector according to the embodiment.
As shown in FIG. 4, the first vehicle detector S1 and the like include a laser range finder S11 and an operation control/vehicle determination unit S12. The first vehicle detector S1 and the like are provided on one of the two islands 40. The operation control/vehicle determination unit S12 includes a CPU (Central Processing Unit) S121, a RAM (Random Access Memory) S122, a ROM (Lead Only Memory) S123, a power supply unit S124, and a communication control unit S125.

The ROM S123 stores the operation control program of the laser rangefinder S11, the object detection program, the vehicle determination program, the first vehicle determination table, the second vehicle determination table, and the like. The CPU S121 controls operations such as laser irradiation and motor drive of the laser rangefinder S11 based on the operation control program stored in the ROM S123, and the RAM S122 responds to the scanning angle output from the laser rangefinder S11. Store the distance value to the object. Further, the CPU S121 uses the object detection program, the vehicle determination program, the first vehicle determination table, and the second vehicle determination table stored in the ROM S123, based on the object (such as a fixed object such as a road surface or a wall or a vehicle). (Non-fixed object) is detected, the presence/absence of a vehicle is determined from the detection result of the object, and the RAM S122 stores the vehicle presence/absence determination result.

The communication control unit S125 communicates with the interface aggregation unit 41 and transmits the vehicle presence/absence determination result to the interface aggregation unit 41. The interface aggregation unit 41 transmits the vehicle presence/absence determination result to the lane server 3, and the lane server 3 outputs a control signal for controlling the operation of the lane equipment 4 based on the vehicle presence/absence determination result. The power supply unit S124 supplies operating power to each unit of the operation control/vehicle determination unit S12.

FIG. 5: is a figure which shows an example of schematic structure of the laser range finder of the vehicle detector which concerns on embodiment. The laser range finder S11 measures the distance by the TOF (Time of Flight) method. The TOF method is a method of measuring the flight time of light and measuring the distance based on the flight time.
As shown in FIG. 5, the laser range finder S11 includes a motor S111, a light projecting unit S112, a light receiving unit S113, and a mirror S114.

The light projecting unit S112 emits a laser beam based on the operation control of the operation control/vehicle determination unit S12, and the motor S111 drives the mirror S114 at a constant speed based on the operation control of the operation control/vehicle determination unit S12. Rotate 360 degrees. For example, by controlling the light receiving unit S113 and performing light reception processing for rotation from 12 degrees to 90 degrees, measurement of a necessary range is performed. Alternatively, a method may be used in which the light projecting unit S112 is controlled and light projection processing is performed with respect to the rotation from 12 degrees to 90 degrees. This rotation (1 cycle) is repeated. The rotating mirror S114 reflects the laser light emitted from the light projecting unit S112. The laser light is radially scanned by the rotation of the mirror S114. For example, laser light is radially scanned in steps of 0.63 degrees, and the laser light radially scanned is reflected by an object such as a vehicle, a wall, or a road surface. The mirror S114 receives the reflected light from the object and guides it to the light receiving unit S113. The light receiving unit S113 detects the reflected light from the mirror S114. In the present embodiment, in order to make the description easy to understand, a case of performing radial scanning in steps of two degrees will be described.

In this way, the laser range finder S11 scans the laser light radially, detects the reflected light of the laser light scanned radially, and based on the detection result of the reflected light of the laser light scanned radially, the laser light The distance value to the object according to the scanning angle of is output (measured). For example, the laser range finder S11 outputs (measures) a distance value to an object according to the forward rotation.

In addition to the laser rangefinder described in the present embodiment, various structures or characteristics such as a method of scanning with a semiconductor such as MEMS (Micro Electro Mechanical Systems) may be applied.

FIG. 6 is a diagram showing an example of installation of a vehicle detector and scanning by a laser range finder.
The first vehicle detector S1 and the like are installed at a certain height (for example, 1600 mm) from the road surface 61 of the lane 49 so that the adverse effect of the measurement due to the splash of mud or water splash from the road surface 61 of the lane 49 can be minimized. Shall be done. The laser rangefinder S11 of the first vehicle detector S1 may be installed at a certain height from the road surface 61 of the lane 49, and the operation control/vehicle determination unit S12 may be installed at another location.

The irradiation angle range may be set to about 120 degrees so as to cover the entire view of the vehicle, or the irradiation angle range may be set to about 60 degrees depending on the detection requirements of the vehicle determination. The detection requirement for vehicle determination is, for example, a requirement to exclude a vehicle such as a crane truck having a long structure at a high place.

Here, a virtual plane 65 is defined on the lane 49 in order to describe the irradiation direction of the laser light emitted from the laser rangefinder S11 such as the first vehicle detector S1. The virtual plane 65 is a plane that intersects (for example, is orthogonal to) the traveling direction of the vehicle on the lane 49 and is perpendicular to the lane 49. The laser range finder S11 is installed on the shoulder of the lane 49, the irradiation direction of the laser beam of the laser range finder S11 is adjusted, and the laser beam is radially irradiated along the virtual plane 65 by this adjustment and the rotation of the mirror S114. It The laser range finder S11 outputs the detection result of the reflected light of the radial laser beam, and the first vehicle detector S1 and the like show the distance value to the object according to the scanning angle of the radial laser beam based on the detection result. Output.

Next, the setting of the initial value by the operation control/vehicle determination unit S12 will be described. The operation control/vehicle determination unit S12 determines the distance value when the vehicle does not exist (the distance value of the lane 49 to the road surface 61, the distance value to the wall 63, and the wall 64) in the measurement range 66 included in the virtual plane 65. After the measurement, the RAM 522 stores the measured value as the zero point (reference point) of the determination process.
(First vehicle determination logic (first vehicle determination process))
Next, an example of the first vehicle determination logic (first vehicle determination processing) will be described with reference to FIGS. 7A, 7B, and 7C. The first vehicle determination logic determines the presence or absence of a vehicle based on the first and second object detections. The first object detection detects the presence or absence of an object from the object detection distance threshold for each scanning angle (FIG. 7B) included in the first vehicle determination table and the distance value to the object according to the scanning angle of the laser light. To do. The second object detection is a predetermined size or more based on the first object detection number threshold value (FIG. 7C) included in the first vehicle determination table and the detection number of the distance value to the object according to the scanning angle of the laser light. Detect objects.

FIG. 7A is a diagram for explaining a first vehicle determination logic (first vehicle determination process) by the vehicle detector according to the embodiment. As shown in FIG. 7A, a plurality of divided areas L10, L11, and L12 obtained by dividing the virtual plane 65 in the direction perpendicular to the lane 49 are defined. For example, the boundary between the road surface 61 (lane 49) and the road side 62 is set as a reference position (0 mm), and the divided area L10 extends from the reference position to the road side 62 up to 250 mm and the range from the reference position to the lane 49 up to 1000 mm. The divided area L11 is defined as the divided area L11, and the divided area L12 is defined in the range from 1000 mm to 3000 mm.

The laser range finder S11 irradiates laser light radially with one point at the installation position as the origin. Therefore, the laser light is dense at the position d1 close to (the origin of) the laser range finder S11, but becomes sparse at the position d2 far from the (origin of) the laser range finder S11. That is, the laser light gradually becomes sparse as the distance from the laser rangefinder S11 increases, and the detection size changes depending on the distance between the laser rangefinder S11 and the object to be detected.

The motion control/vehicle determination unit S12 determines the presence of a vehicle when the first object detection detects an object in a certain range and the second object detection detects an object of a predetermined size or more. Run the logic. By adopting the first vehicle determination logic, the processing load is reduced and the responsiveness is ensured.

FIG. 7B is a first vehicle detection including an object detection distance threshold T1 for detecting the presence or absence of an object (non-fixed object) by the first object detection of the first vehicle determination logic by the vehicle detector according to the embodiment. It is a figure which shows an example of a table. FIG. 7C is a first object detection number for each divided area for detecting an object (non-fixed object) having a predetermined size or more by the second object detection of the first vehicle determination logic by the vehicle detector according to the embodiment. It is a figure which shows an example of a threshold value.
As shown in the first vehicle detection table of FIG. 7B, the object detection distance threshold T1 according to each divided area L10, L11, and L12 (distance range for determining the presence or absence of an object (non-fixed object) in each divided area) To set. Furthermore, as described above, since the detection size changes depending on the object position in the measurement range, as shown in the first vehicle detection table of FIG. 7C, the first object corresponding to each divided area L10, L11, and L12. A detection number threshold value (a detection number for detecting an object (non-fixed object) having a predetermined size or more in each divided area) is set.

As shown in FIG. 7B, for example, the first vehicle detection table indicates that the laser light emitted in the scanning angle range of 12.00 or more and 50.00 or less passes through the divided area L10. In addition, the first vehicle detection table shows a distance from the origin of the laser light emitted at the scanning angle of 12.00 to the start position of the divided area L10 (the position of 250 mm from the reference position toward the road side 62) of 1202 mm or more. , And an object detection distance threshold T1_12.00_L10 (1202 mm≦object detection distance) that is less than 1431 mm indicating the distance from the origin of the laser light emitted at the scanning angle of 12.00 to the end position (reference position) of the divided area L10. Threshold value T1_12.00_L10<1431 mm) is included.

Further, the first vehicle detection table shows that the laser light emitted in the range of the scanning angle of 22.00 or more and 74.00 or less passes through the divided area L11. For example, the first vehicle detection table irradiates at a scanning angle of 22.00 or more indicating the distance from the origin of the laser light emitted at the scanning angle of 22.00 to the start position (reference position) of the divided area L11 and at the scanning angle of 22.00. Object detection distance threshold T1_22.00_L11 (1335 mm≦object detection distance) that is less than 1510 mm and indicates the distance from the origin of the laser beam to the end position of the divided area L11 (the position of 1000 mm from the reference position to the lane 49) Threshold value T1_22.00_L11<1510 mm) is included.

Further, in the first vehicle detection table, the laser light emitted in the scanning angle range of 48.00 or more and 82.00 or less passes through the division area L12. For example, the distance from the origin of the laser light emitted at the scanning angle of 48.00 to the start position (reference position) of the divided area L12 is 2018 mm or more, and the laser light emitted at the scanning angle of 48.00 is divided from the origin. An object detection distance threshold T1_48.00_L12 (2018 mm≦object detection distance threshold T1_48.00_L12<2092 mm) within a range of less than 2092 mm indicating a distance from the end position of the area L12 (position of 3000 mm toward the lane 49 from the reference position) is set. Including.

As shown in FIG. 7C, for example, in the first vehicle detection table, “3” is set as the first object detection number threshold value corresponding to the divided area L10, and “3” is set as the first object detection number threshold value corresponding to the divided area L11. 2", and "1" is included as the first object detection number threshold value corresponding to the divided area L12. When the number of detected objects in the divided area L10 becomes equal to or larger than the first object detection number threshold “3” corresponding to the divided area L10, it is detected that there is an object having a predetermined size or more in the divided area L10. Similarly, when the number of detected objects in the divided area L11 becomes equal to or larger than the first object detection number threshold “2” corresponding to the divided area L11, it is detected that there is an object having a predetermined size or more in the divided area L11. Similarly, when the number of detected objects in the divided area L12 becomes equal to or larger than the first object detection number threshold “1” corresponding to the divided area L12, it is detected that there is an object having a predetermined size or more in the divided area L12.
(Second vehicle determination logic (second vehicle determination process))
Next, an example of the second vehicle determination logic (second vehicle determination logic) will be described with reference to FIGS. 8A, 8B, and 8C. The second vehicle determination logic (second vehicle determination logic) determines the presence/absence of a vehicle based on the third and fourth object detections. The third object detection is the presence/absence of a non-fixed object in each area based on the fixed object detection distance threshold (FIG. 8B) for each scanning angle corresponding to each area and the distance value to the object according to the scanning angle of the laser beam. To detect. The fourth object detection is performed in each area based on the second object detection number threshold value (FIG. 8C) for each scanning angle corresponding to each area and the detection number of the distance value to the object according to the scanning angle of the laser beam. Detects non-fixed objects of a certain size or larger.

FIG. 8A is a diagram for explaining a second vehicle determination logic (second vehicle determination process) by the vehicle detector according to the embodiment. The second vehicle determination logic is a logic that relieves the case where the distance value data with the accuracy required for vehicle detection is not output. As a characteristic of the laser rangefinder S11, it is difficult to obtain sufficient reflected light from a vehicle of a color that absorbs light (black or black vehicle), and a distance measurement error may occur. For example, since reflected light cannot be obtained, the distance value may be 0 mm in some cases. According to the first determination logic based on the first vehicle detection table, the vehicle determination is not applicable because the distance value is 0 mm, and there is an error that the vehicle does not exist in spite of the presence of the black or black type vehicle. The judgment may be output. Even in such a case, the presence of the vehicle can be correctly determined by the second vehicle determination logic.

When there is no vehicle, the first vehicle detector S1 or the like measures a distance value to a fixed object such as the road surface 61, the wall 63, or the wall 64. That is, the first vehicle detector S1 and the like measure the same distance value (distance value to the fixed object) when there is no vehicle. Therefore, the first vehicle detector S1 and the like measure a distance value (distance value data of 0 mm in the case of a black or black-colored vehicle) deviating from the distance value to the fixed object obtained when the vehicle does not exist. In this case, it is determined that there is a non-fixed object.

The first vehicle detector S1 and the like correspond to an assumed distance range to a fixed object such as the road surface 61, the wall 63, or the wall 64, in consideration of the swing width (margin) corresponding to the measurement error of the distance meter S11. The fixed object detection distance threshold T2 is set.

FIG. 8B is a second vehicle detection table including a fixed object detection distance threshold T2 for detecting an object (non-fixed object) by the third object detection of the second vehicle determination logic by the vehicle detector according to the embodiment. It is a figure which shows an example. In addition, FIG. 8C is a second object detection number threshold for each area for detecting a non-fixed object having a predetermined size or more by the fourth object detection of the second vehicle determination logic by the vehicle detector according to the embodiment. It is a figure which shows an example.

The second vehicle detection table includes a fixed object detection distance threshold T2 corresponding to the assumed distance range to the fixed object. When no vehicle is present on the lane 49, as shown in FIGS. 8A and 8B, the laser light emitted in the lane scanning angle range of 18.00 to 64.00 is reflected by the area L20 corresponding to the road surface 61. Further, the laser light emitted in the range of the lane scanning angle of 66.00 or more and 70.00 or less is reflected by the area L21 corresponding to the wall 64, and the lane scanning angle of 74.00 or more and 90.00 or less. The laser light emitted in the range is reflected by the area L22 corresponding to the wall 63. The first vehicle detector S1 and the like detect reflected light corresponding to the emitted laser light and measure a distance value to a fixed object. When there is no vehicle on the lane 49, the distance value measured here is included in the assumed distance range (range of the fixed object detection distance threshold T2) including an error.

As shown in FIG. 8B, for example, in the second vehicle detection table, the fixed object detection distance threshold T2_18.00_L20 (1472 mm≦, which is in the range of 1472 mm or more and less than 1893 mm corresponding to the laser beam emitted at the scanning angle of 18.00). Fixed object detection distance threshold T2 — 18.00_L20≦1893 mm) is included. In addition, the second vehicle detection table is a fixed object detection distance threshold T2_66.00_L21 (3612 mm≦fixed object detection distance threshold T2_66.L21) in the range of 3612 mm or more and less than 4050 mm corresponding to the laser light emitted at the scanning angle of 66.00. 00_L21≦4050 mm). In addition, the second vehicle detection table has a fixed object detection distance threshold T2_72.00_L22 (4011 mm≦fixed object detection distance threshold T2_72.72) in the range of 4011 mm or more and less than 4433 mm corresponding to the laser beam emitted at the scanning angle of 72.00. 00_L22≦4433 mm).

When the distance value from the laser rangefinder S11 is included in the fixed object detection distance threshold T2, the first vehicle detector S1 or the like detects a fixed object such as the road surface 61, the wall 63, or the wall 64, and detects the laser distance. When the distance value from the total S11 exceeds the range of the fixed object detection distance threshold T2, the non-fixed object is detected.

As shown in FIG. 8C, for example, in the second vehicle detection table, the second object detection number threshold corresponding to the area L20 is “1”, and the second object detection number threshold corresponding to the area L21 is “1”. , "2" is included as the second object detection number threshold value corresponding to the area L22. When the number of detected objects in the area L20 becomes equal to or larger than the second object detection number threshold “1” corresponding to the area L20, it is detected that there is an object having a predetermined size or more in the area L20. Similarly, when the number of detected objects in the area L21 becomes equal to or larger than the second object detection number threshold “1” corresponding to the area L21, it is detected that there is an object having a predetermined size or more in the area L21. Similarly, when the number of detected objects in the area L22 becomes equal to or larger than the second object detection number threshold “2” corresponding to the area L22, it is detected that there is an object having a predetermined size or more in the area L22.

Next, with reference to FIG. 9, the presence/absence of a vehicle based on the first vehicle determination logic including the first and second object detections and the second vehicle determination logic including the third and fourth object detections is determined. The determination process will be described. FIG. 9 is an example of a process of determining the presence or absence of a vehicle based on a first vehicle determination logic including first and second object detections and a second vehicle determination logic including third and fourth object detections. It is a flowchart shown.

In addition, in the present embodiment, a process of determining the presence or absence of a vehicle based on the first and second vehicle determination logics will be described, but the first and second vehicle determination logics are not essential and are required. The presence/absence of a vehicle may be determined based on the first vehicle determination logic according to the condition, the first vehicle determination logic may be combined with another vehicle determination logic, and the first and the second determination logics may be combined. The second vehicle determination logic may be combined with another vehicle determination logic.

The first vehicle detector S1 and the like perform initial setting and set the first and second vehicle detection tables (step ST100). For example, in a state where no vehicle is present on the lane 49, the operation control/vehicle determination unit S12 of the first vehicle detector S1 drives the motor S111 to rotate the mirror S114 to emit the laser beam from the light projecting unit S112. The second vehicle detection table is set on the basis of the detection result of the reflected light by irradiating and radially scanning the laser light. The operation control/vehicle determination unit S12 also sets the first vehicle detection table based on the detection result of the reflected light and the arrangement information of the divided areas L10, L11, and L12 set in advance. Alternatively, the operation control/vehicle determination unit S12 of the first vehicle detector S1 receives the first and second vehicle detection tables from the host server such as the lane server 3 and receives the received first and second vehicle detections. The table may be set, or the first and second vehicle detection tables stored in various information storage media may be received, and the received first and second vehicle detection tables may be set. Good.

After the initial setting is completed, the first vehicle detector S1 and the like start vehicle detection. The operation control/vehicle determination unit S12 drives the motor S111, rotates the mirror S114, irradiates the laser beam from the light projecting unit S112, scans the laser beam radially, and starts measurement for each cycle ( Step ST101).

The operation control/vehicle determination unit S12 receives the distance value measured by the laser range finder S11 in response to the radial scanning of the laser light (step ST102). For example, the motion control/vehicle determination unit S12 receives a distance value corresponding to a radial scan in increments of 2 degrees from 12 degrees to 90 degrees.

The operation control/vehicle determination unit S12 executes the first object detection of the first vehicle determination logic, and the distance value is first for each of the divided areas L10, L11, and L12 associated with the scanning angle of the laser light. Whether or not it is included in the range of the object detection distance threshold T1 of the vehicle detection table of No. 1 or the third object detection of the second vehicle determination logic is executed, and the divided area L10 is associated with the scanning angle of the laser beam, It is determined for each of L11 and L12 whether or not the distance value exceeds the range of the fixed object detection distance threshold T2 of the second vehicle detection table (step ST103). Based on these determinations, non-fixed objects such as the vehicle 5 other than fixed objects such as the road surface 61, the wall 63, or the wall 64 are detected.

Further, the operation control/vehicle determination unit S12 executes the second object detection of the first vehicle determination logic, and determines the distance value for each of the divided areas L10, L11, and L12 associated with the scanning angle of the laser light. It is determined whether the number of detections is equal to or more than the first object detection number threshold value of the first vehicle detection table, and the fourth object detection of the second vehicle determination logic is executed to correspond to the scanning angle of the laser light. For each of the divided areas L10, L11, and L12 to be attached, it is determined whether or not the number of detections of the distance value is equal to or more than the second object detection number threshold of the second vehicle detection table (steps ST106 to ST111). By these determinations, an object having a certain size or more is detected. An example will be described below.

For example, when the distance value measured from the reflected light of the laser beam with the scanning angle of 16.00 degrees is included in the range from 907 mm to less than 1456 mm, the operation control/vehicle determination unit S12 (corresponding to 16.00 degrees in FIG. 7B). Then, it is determined that there is an object (non-fixed object) in L10, and the number of detections in L10 is counted up (+1) (step ST106). Further, when the distance value measured from the reflected light of the laser beam having the scanning angle of 18.00 degrees is included in the range from 809 mm to less than 1472 mm (corresponding to 18.00 degrees in FIG. 7B, the operation control/vehicle determination unit S12). Then, it is determined that there is an object (non-fixed object) in L10, and the number of detections in L10 is counted up (+1) (step ST106). Furthermore, when the distance value measured from the reflected light of the laser beam having the scanning angle of 20.00 degrees is included in the range of 731 mm or more and less than 1490 mm (corresponding to 20.00 degrees in FIG. 7B, Then, it is determined that there is an object (non-fixed object) in L10, and the number of detections in L10 is counted up (+1) (step ST106). As described above, the operation control/vehicle determination unit S12 detects the first object detection number threshold “3” or more set in the divided area L10 shown in FIG. 7C (YES in step ST107), and L10 has a predetermined size or more. The presence of a vehicle is determined based on the detection of the object (non-fixed object) (step ST112), and the vehicle presence result is output (transmitted) (step ST113). If the measurement results of a plurality of cycles within a certain time (step ST104, NO) satisfy the condition of the first object detection number threshold (step ST107, YES), it is determined that there is a vehicle (step ST112). The presence result is output (transmitted) (step ST113). The count value that has exceeded a certain time since the measurement is cleared (-1).

Alternatively, when the distance value measured from the reflected light of the laser beam with the scanning angle of 30.00 degrees is included in the range of 1000 mm or more and less than 1617 mm (the operation control/vehicle determination unit S12 corresponds to 30.00 degrees in FIG. 7B). (See the distance value of L11), it is determined that there is an object in L11, and the number of detections of L11 is counted up (+1) (step ST108). Further, when the distance value measured from the reflected light of the laser beam having the scanning angle of 32.00 degrees is included in the range of 944 mm or more and less than 1651 mm (corresponding to 32.00 degrees in FIG. 7B, the operation control/vehicle determination unit S12). (See the distance value of L11), it is determined that there is an object in L11, and the number of detections of L11 is counted up (+1) (step ST108). As described above, the operation control/vehicle determination unit S12 detects the first object detection number threshold “2” or more set in the divided area L11 shown in FIG. 7C (YES in step ST109), and L11 has a predetermined size or more. The presence of a vehicle is determined based on the detection of the object (non-fixed object) (step ST112), and the vehicle presence result is output (transmitted) (step ST113). If the measurement results of a plurality of cycles within a certain time (step ST104, NO) satisfy the condition of the first object detection number threshold (step ST109, YES), it is determined that there is a vehicle (step ST112). The presence result is output (transmitted) (step ST113). The count value that has exceeded a certain time since the measurement is cleared (-1).

Alternatively, when the distance value measured from the reflected light of the laser beam with the scanning angle of 60.00 degrees is included in the range of 1732 mm or more and less than 2800 mm, the operation control/vehicle determination unit S12 (corresponds to 60.00 degrees in FIG. 7B). (See the distance value of L12), it is determined that there is an object in L12, and the number of detections of L12 is incremented (+1) (step ST110). As described above, the motion control/vehicle determination unit S12 detects the first object detection number threshold “1” or more set in the divided area L12 shown in FIG. 7C (YES in step ST111), and L12 has a predetermined size or more. The presence of a vehicle is determined based on the detection of the object (non-fixed object) (step ST112), and the vehicle presence result is output (transmitted) (step ST113). In addition, when the measurement result of a plurality of cycles within a fixed time (step ST104, NO) satisfies the condition of the first object detection number threshold (step ST111, YES), it is determined that there is a vehicle (step ST112), The presence result is output (transmitted) (step ST113). The count value that has exceeded a certain time since the measurement is cleared (-1).

Alternatively, when the distance value measured from the reflected light of the laser light with the scanning angle of 20.00 degrees exceeds 1916 mm, the motion control/vehicle determination unit S12 determines (the distance of L20 corresponding to 20.00 degrees in FIG. 8B). (See the value), it is determined that there is an object in L20, and the number of detections in L20 is counted up (+1) (step ST106). As described above, the motion control/vehicle determination unit S12 detects the first object detection number threshold “1” or more set in the area L20 shown in FIG. 8C (step ST107, YES), and L20 detects an object of a predetermined size or more. The presence of a vehicle is determined based on the detection of (non-fixed object) (step ST112), and the vehicle presence result is output (transmitted) (step ST113). In addition, when the measurement result of a plurality of cycles within a fixed time (step ST104, NO) satisfies the condition of the first object detection number threshold (step ST107, YES), it is determined that there is a vehicle (step ST112). The presence result is output (transmitted) (step ST113). The count value that has exceeded a certain time since the measurement is cleared (-1).

Alternatively, when the distance value measured from the reflected light of the laser beam with the scanning angle of 70.00 degrees exceeds 4679 mm, the motion control/vehicle determination unit S12 determines (the distance of L21 corresponding to 70.00 degrees in FIG. 8B). (See the value), it is determined that there is an object in L21, and the number of detections in L21 is counted up (+1) (step ST108). As described above, the motion control/vehicle determination unit S12 detects the second object detection number threshold “1” or more set in the area L21 shown in FIG. 8C (YES in step ST109), and L21 has an object of a predetermined size or more. The presence of a vehicle is determined based on the detection of (non-fixed object) (step ST112), and the vehicle presence result is output (transmitted) (step ST113). In addition, when the measurement results of a plurality of cycles within a certain time (step ST104, NO) satisfy the condition of the second object detection number threshold (step ST109, YES), it is determined that there is a vehicle (step ST112). The presence result is output (transmitted) (step ST113). The count value that has exceeded a certain time since the measurement is cleared (-1).

Alternatively, when the distance value measured from the reflected light of the laser light with the scanning angle of 80.00 degrees exceeds 4274 mm, the motion control/vehicle determination unit S12 determines (the distance of L22 corresponding to 80.00 degrees in FIG. 8C). (See the value), it is determined that there is an object in L22, and the number of detections in L22 is counted up (+1) (step ST110). Furthermore, when the distance value measured from the reflected light of the laser beam with the scanning angle of 82.00 degrees exceeds 4248 mm, the motion control/vehicle determination unit S12 determines (the distance of L22 corresponding to 82.00 degrees in FIG. 8C). (See the value), it is determined that there is an object in L22, and the number of detections in L22 is counted up (+1) (step ST110). As described above, the operation control/vehicle determination unit S12 detects the second object detection number threshold “2” or more set in the area L22 shown in FIG. 8C (YES in step ST111), and L22 has an object of a predetermined size or more. The presence of a vehicle is determined based on the detection of (non-fixed object) (step ST112), and the vehicle presence result is output (transmitted) (step ST113). In addition, when the measurement results of a plurality of cycles within a certain time (step ST104, NO) satisfy the condition of the second object detection number threshold (step ST111, YES), the presence of the vehicle is determined (step ST112), and the vehicle is determined. The presence result is output (transmitted) (step ST113). The count value that has exceeded a certain time since the measurement is cleared (-1).

The motion control/vehicle determination unit S12 does not include the measured distance value in the range of the object detection distance threshold T1 of the first vehicle detection table and exceeds the fixed object detection distance threshold T2 of the second vehicle detection table. If there is no vehicle, it is determined that there is no vehicle, and the result of no vehicle is output (transmitted) (step ST105). If none of steps ST107, 109, and 111 determines that the number of detected objects is equal to or more than the first or second object detection number threshold, the operation control/vehicle determination unit S12 determines that there is no vehicle, and the vehicle-free result is obtained. Is output (transmitted) (step ST105).

The first vehicle detector S1 and the like according to the present embodiment use the first vehicle determination logic to detect an object (non-fixed object) for each of the plurality of divided areas L10, L11, and L12. (See FIG. 7B), and a first object detection number threshold value (see FIG. 7C) for detecting an object having a predetermined size or more from the object detection number for each of the plurality of divided areas L10, L11, and L12, A non-fixed object having a predetermined size or more can be determined as a vehicle for each of the plurality of divided areas L10, L11, and L12. This makes it possible to improve the efficiency and accuracy of the vehicle presence/absence determination.

Further, the first vehicle detector S1 and the like according to the present embodiment uses the second vehicle determination logic to detect a fixed object for each of the plurality of areas L20, L21, and L22, and the fixed object detection distance threshold T2 (see FIG. 8B), and a second object detection number threshold value (see FIG. 8C) for detecting an object having a predetermined size or more from the object detection number that absorbs light for each of the plurality of areas L20, L21, and L22. An object that absorbs light of a predetermined size or more can be determined as a vehicle for each of the plurality of areas L20, L21, and L22. This makes it possible to improve the efficiency and accuracy of the vehicle presence/absence determination.

According to this embodiment, at least one of the first and second vehicle determination logics is used to exclude objects other than the vehicle (rain, snow, dead leaves, flying debris, small animals (birds), people, etc.). It can be eliminated as a vehicle, and the vehicle can be detected efficiently and highly accurately. In addition, the first vehicle detector S1 and the like detect an object based on the reflected light of the laser light emitted from the laser rangefinder from the object, and therefore, one of the corresponding two islands 40 is not detected. It only needs to be installed and is easy to install.

Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the scope equivalent thereto.

1... Central apparatus 2... Tollgate server 3... Lane server 4... Lane equipment 5... Vehicle 40... Island 41... Interface aggregation unit 42... Roadside display 43... Receiving machine 44... Start control machine 45... Lane monitoring camera 46... 1st antenna 47... 2nd antenna 48... Booth 49... Lane 51... Onboard equipment 52... ETC card 61... Road surface 62... Roadside 63... Wall 64... Wall 65... Virtual plane 66... Measurement range 401... Interface aggregation part S1... First vehicle detector S2... Second vehicle detector S4... Third vehicle detector S11... Laser range finder S111... Motor S112... Projector S113... Light receiver S114... Mirror S12... Operation control/vehicle determination unit S121... CPU
S122... RAM
S123...ROM
S124... Power supply unit S125... Communication control unit

Claims (8)

A laser beam is radially scanned along a virtual plane that intersects the traveling direction of the vehicle on the lane and is perpendicular to the lane, and the scanning angle of the laser beam is set based on the detection result of the reflected light of the laser beam that is radially scanned. A rangefinder that measures the distance value to the corresponding object,
A determination unit that executes a first vehicle determination process that determines the presence or absence of the vehicle based on first and second object detection,
The determination unit,
From the object detection distance threshold for each scanning angle included in the first vehicle determination table and the distance value to the object according to the scanning angle of the laser light, the first object detection for detecting the presence or absence of the object is executed,
The second object for detecting an object having a predetermined size or more from the first object detection number threshold included in the first vehicle determination table and the detection number of the distance value to the object according to the scanning angle of the laser beam. Perform detection,
Vehicle detection device comprising. Defining a plurality of divided areas obtained by dividing the virtual plane in the direction perpendicular to the lane, and defining the range of the scanning angle of the laser light included in each divided area,
The determination unit detects the presence or absence of an object in each divided area from the object detection distance threshold value for each scanning angle corresponding to each divided area and the distance value to the object according to the scanning angle of the laser beam. The vehicle detection device according to claim 1, wherein the object detection is performed. The determination unit detects an object when the distance value to the object according to the scanning angle of the laser beam is included in the range of the object detection distance threshold for each scanning angle corresponding to each divided area. Vehicle detection device. Based on the first object detection number threshold value for each scanning angle corresponding to each divided area and the number of detections of the distance value to the object according to the scanning angle of the laser beam, the determination unit determines a predetermined size or more in each divided area. The vehicle detection device according to claim 2 or 3, which executes the second object detection for detecting the object. The determination unit,
The third object detection for detecting the presence/absence of a non-fixed object is executed from the fixed object detection distance threshold for each scanning angle included in the second vehicle determination table and the distance value to the object according to the scanning angle of the laser beam. Then
A fourth object detecting a non-fixed object having a predetermined size or more based on the second object detection number threshold included in the second vehicle determination table and the detection number of the distance value to the object according to the scanning angle of the laser beam. Perform object detection,
The vehicle detection device according to any one of claims 1 to 4, which executes a second vehicle determination process for determining the presence or absence of the vehicle based on the detection of the third and fourth objects. The vehicle detection device according to claim 5, wherein the determination unit detects a non-fixed object when a distance value to the object according to a scanning angle of the laser light exceeds a range of the fixed object detection distance threshold for each scanning angle. .. A laser beam is radially scanned along a virtual plane that intersects the traveling direction of the vehicle on the lane and is perpendicular to the lane, and the scanning angle of the laser beam is set based on the detection result of the reflected light of the laser beam that is radially scanned. Measure the distance value to the corresponding object,
The first object detection that detects the presence or absence of an object is executed from the object detection distance threshold for each scanning angle included in the first vehicle determination table and the distance value to the object according to the scanning angle of the laser light,
A second object detection for detecting the size of the object is executed from the first object detection number threshold included in the first vehicle determination table and the distance value to the object according to the scanning angle of the laser light,
A vehicle detection method for executing a first vehicle determination process for determining the presence or absence of the vehicle based on the detection of the first and second objects. The third object detection for detecting the presence/absence of a non-fixed object is executed from the fixed object detection distance threshold for each scanning angle included in the second vehicle determination table and the distance value to the object according to the scanning angle of the laser beam. Then
The fourth object detection for detecting the size of the non-fixed object is executed based on the second object detection number threshold included in the second vehicle determination table and the distance value to the object according to the scanning angle of the laser light. ,
The vehicle detection method according to claim 7, wherein a second vehicle determination process for determining the presence/absence of the vehicle is executed based on the detection of the third and fourth objects.