JP2013045165A - Mobile rotating body detecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mobile rotating body detecting device having high stability and capable of highly accurately detecting a mobile rotating body in non-contact therewith.SOLUTION: The mobile rotating body detecting device according to an embodiment includes: speed information acquiring means that is provided at a side of a moving path on which a mobile body having rotating bodies at side parts moves, and acquires speed information of the rotating bodies to the rotation in the direction perpendicular to the surface of the moving path; and rotating body detecting means that detects the rotating bodies by performing a detecting process of a speed pattern recognizable as the rotating bodies, on the basis of the speed information acquired by the speed information acquiring means.

Description

  Embodiments described herein relate generally to a moving rotator detection apparatus.

  In ETC (ETC: registered trademark) system that automatically collects tolls for vehicles that use toll roads such as expressways, and parking lot management systems that manage toll parking lots Therefore, it is necessary to detect the number of axles (number of wheels) of the vehicle.

  As a moving rotating body detection device used for such a purpose, for example, a tread board method and a laser scanning method are known. The tread board method recognizes the number of wheels by detecting the pressure applied by the wheels of the sensors embedded in the road, and the laser scan method scans the side surface of the traveling vehicle with a pulsed laser beam. From the obtained distance information, an object in contact with the ground is detected and recognized as a wheel.

  However, the tread board system has a drawback that the sensor life is short because a road-embedded sensor is used, and the vehicle length is not known by the sensor alone. On the other hand, the laser scanning method is non-contact, but has a problem that the scanning speed is not sufficient for a high-speed moving body.

JP-A-2-219198 JP 2000-339586 A

  The problem to be solved by the present invention is to provide a moving rotator detection device that can detect a moving rotator with high accuracy without contact and is excellent in stability.

  The moving rotating body detection device according to the embodiment is provided at a side portion of a moving path along which a moving body having a rotating body moves on a side portion, and speed information for rotation of the rotating body in a direction perpendicular to the surface of the moving path. And a rotating body detecting means for detecting the rotating body by performing a detection process of a speed pattern that can be recognized as a rotating body based on the speed information acquired by the speed information acquiring means. doing.

1 is a block diagram schematically showing the configuration of a moving rotator detection apparatus according to a first embodiment. The schematic diagram which shows the example of arrangement | positioning of the speed information input part in the toll gate of the toll road which concerns on 1st Embodiment. The schematic diagram seen from the front of the road explaining the example of arrangement | positioning of the speed information input part which concerns on 1st Embodiment. The schematic diagram seen from the side of the road explaining the example of arrangement | positioning of the speed information input part which concerns on 1st Embodiment. The graph which shows an example of the speed information of the wheel obtained from the speed information input part which concerns on 1st Embodiment. The graph which shows an example of the significant speed information converted from the speed information of the wheel of FIG. The flowchart explaining the operation | movement which concerns on 1st Embodiment. The figure which shows typically a mode that the speed information of the wheel input by the speed information input part which concerns on 1st Embodiment was stored in RAM. The figure which shows typically a mode that the converted significant speed information which concerns on 1st Embodiment was stored in RAM. The flowchart explaining the speed direction confirmation process which concerns on 1st Embodiment. The block diagram which shows roughly the structure of the moving rotary body detection apparatus which concerns on 2nd Embodiment. The schematic diagram seen from the front of the road explaining the example of arrangement | positioning of the speed information input part which concerns on 2nd Embodiment. The schematic diagram seen from the side of the road explaining the example of arrangement | positioning of the speed information input part which concerns on 2nd Embodiment. The schematic diagram seen from right above the road explaining the example of arrangement | positioning of the speed information input part which concerns on 2nd Embodiment. The schematic diagram explaining the center distance of the wheel which concerns on 2nd Embodiment. The flowchart explaining the operation | movement which concerns on 2nd Embodiment. The figure which shows typically a mode that the speed information of the wheel after correction | amendment which concerns on 2nd Embodiment was stored in RAM. The figure which shows typically a mode that the produced vehicle presence / absence signal which concerns on 2nd Embodiment was stored in RAM. The graph which shows an example of the produced vehicle presence / absence signal which concerns on 2nd Embodiment. The schematic diagram for demonstrating the calculation of the center distance which concerns on 2nd Embodiment. The schematic diagram which shows the structure of a spatial filter type speedometer roughly. The schematic diagram which shows the principal part of a spatial filter type speedometer roughly. The schematic diagram seen from the front of the road explaining the example of arrangement | positioning in the case of applying a spatial filter type speedometer to the speed information input part of 1st Embodiment. The schematic diagram seen from the side of the road explaining the example of arrangement | positioning in the case of applying a spatial filter type speedometer to the speed information input part of 1st Embodiment. The schematic diagram seen from the front of the road explaining the example of arrangement | positioning in the case of applying a spatial filter type speedometer to the speed information input part of 2nd Embodiment. The schematic diagram seen from right above the road explaining the example of arrangement | positioning in the case of applying a spatial filter type | formula speedometer to the speed information input part of 1st Embodiment.

Hereinafter, a moving rotating body detection apparatus according to an embodiment will be described with reference to the drawings.
In the following description, a case is described in which a vehicle (automobile) in which a moving body travels and the moving rotator is a wheel of the vehicle. However, the present invention is not limited to this. Etc.) and its wheels are also applicable.

First, the first embodiment will be described.
FIG. 1 schematically shows the configuration of a moving rotator detection apparatus according to the first embodiment. The moving rotator detection apparatus according to the first embodiment is provided on a side portion of a road (moving path) on which the vehicle (moving body) travels, and rotates in the direction perpendicular to the surface of the moving path of the wheels of the vehicle. Speed information input unit 11 as speed information acquisition means for acquiring speed information with respect to the speed information processing unit that converts the speed information acquired by the speed information input unit 11 to significant speed information by comparing with a preset threshold value Rotating body as a rotating body detecting means for detecting the wheel by performing a speed pattern detecting process capable of being recognized as a wheel based on significant speed information converted by the speed information processing section 12 The detection unit 13 is composed of a data bus and an address bus 14 that connect these components so as to communicate with each other.

Hereinafter, each part will be described in detail.
For example, as shown in FIG. 2, the speed information input unit 11 displays the road 21 on an island 22 provided on one side of a road (toll collection lane) 21 at a toll gate of a toll road. It is installed so as to face the side surface of a vehicle (for example, an automobile) 23 traveling in the direction. In FIG. 2, reference numeral 24 denotes an island provided on the other side of the road 21, and reference numeral 25 denotes a roadside antenna for performing wireless communication with the vehicle-mounted device mounted on the vehicle 23.

  The speed information input unit 11 is configured by, for example, a microwave Doppler sensor. Since the microwave Doppler sensor is a known technique, a detailed description thereof is omitted. As shown in FIG. 3, a microwave Doppler sensor includes a transmitter that transmits microwaves and a receiver that receives reflected waves from a detected object. The sensor unit 11a and the horn antenna unit 11b are configured to change the wavelength of the microwave reflected from a moving body that moves in a direction opposite to the microwave transmission direction (referred to as the Doppler effect). It is a sensor (speedometer) that detects speed, and is used in a speedometer and the like.

  In the present embodiment, for the purpose of recognizing the rotation of a moving rotating body (moving rotating body), that is, a wheel (tire), without being affected by the moving speed of the vehicle (automobile), as shown in FIGS. It is characterized by being installed obliquely downward from just beside the traveling direction of 23 and irradiating the side surface of the wheel (tire) 26 with microwaves in a spot shape. By performing such an arrangement, in principle, the speed in the traveling direction of the vehicle 23 is not detected, and the rotation direction of the wheels (tires) 26 (mainly upward U and downward D (perpendicular to the surface of the road 21). Only the velocity component in the direction)) can be detected.

  The speed information processing unit 12 is realized by, for example, a program installed in a CPU (Central Processing Unit), and a threshold value set in advance for speed information (see FIG. 5) input from the speed information input unit 11. Is converted into significant speed information as shown in FIG.

  The rotating body detection unit 3 is constituted by, for example, a CPU (Central Processing Unit), a DSP (Digital Signal Processor), etc., and performs positive / negative speed pattern detection processing that seems to be a rotating body (wheel). Here, the speed pattern that seems to be a rotating body is a negative speed at the beginning of a forward run, once it returns to zero at the center of the wheel, then becomes a positive speed, and vice versa for a reverse run. It is based on becoming. Since the number of samples (time) of the pattern varies depending on the speed, it is also characterized in that a margin is provided for the number of samples.

Next, with the above configuration, the operation according to the first embodiment will be described with reference to the flowchart shown in FIG.
In the following description, a case will be described in which the wheels 26 of the vehicle 23 traveling at the toll gate on the toll road as shown in FIG. 2 are detected.

  As shown in FIGS. 3 and 4, the speed information input unit (microwave Doppler sensor) 11 is installed and measured obliquely downward from right next to the traveling direction of the vehicle 23, so that the speed information of the wheels 26 is obtained. Is obtained (step S1). Here, the obtained speed information of the wheel 26 is shown in a graph as shown in FIG. 5, for example. As described above, when the vehicle 23 travels in the forward direction, the speed in the negative direction is detected in the first half of the wheel 26, and the speed in the positive direction is detected in the second half.

  The speed information of the wheel 26 input by the speed information input unit 11 is stored one-dimensionally in a RAM (random access memory) provided in the speed information processing unit 12. This is schematically shown in FIG. 8, which corresponds to FIG.

  Next, the speed information processing unit 12 converts the speed information stored one-dimensionally in the RAM into significant speed information by comparing it with a predetermined threshold (for example, 2 km / h) set in advance. The positive and negative speed directions are determined (step S2). FIG. 9 schematically shows a state in which the result is stored one-dimensionally in a RAM provided in the speed information processing unit 12, and this corresponds to FIG.

  Here, the definition of the velocity direction (V) is “1” when the velocity is positive, “−1” when the velocity is negative, and “0” when neither of them applies (when a significant velocity cannot be detected). " Such threshold processing makes it possible to remove noise due to the environment.

  Next, the rotator detection unit 13 detects, for example, a pattern in which V = −1 is 3 times or more and V = 1 is 3 times or more of the significant speed information converted by the speed information processing unit 12. Is detected across the state of V = 0, it is determined that there is one wheel (rotating body) (step S3). In the case of the specific example of FIG. 9, it is recognized that there are wheels (tires) at addresses 18 to 40 and addresses 61 to 83, respectively.

  Next, the speed direction determination process in step S2 will be described with reference to the flowchart shown in FIG.

  When the speed information of the wheel 26 is input by the speed information input unit 11 (step S11), it is determined whether or not the speed information is positive (step S12). If the speed information is positive, the absolute value of the speed information is a threshold value. It is determined whether it is larger than (2 km / h) (step S13). If the absolute value of the speed information is larger than the threshold value (2 km / h) as a result of this determination, the speed direction (V) is set to “+1” (step S14), and the process ends.

  If the speed information is not positive in step S12, it is determined whether or not the absolute value of the speed information is larger than a threshold value (2 km / h) (step S15). If the absolute value of the speed information is larger than the threshold value (2 km / h) as a result of this determination, the speed direction (V) is set to “−1” (step S16), and the process ends.

  When the absolute value of the speed information is not larger than the threshold value (2 km / h) in step S13, or when the absolute value of the speed information is not larger than the threshold value (2 km / h) in step S15, the speed direction (V) is changed. “0” is set (step S17), and the process is terminated.

Next, a second embodiment will be described.
FIG. 11 schematically shows the configuration of the moving rotator detection apparatus according to the second embodiment. The second embodiment is different from the first embodiment in that the speed information input unit 15 is provided at a side portion of the road on which the vehicle travels and serves as speed information acquisition means for acquiring speed information of the vehicle moving on the road. The vehicle speed calculation unit 16 as a vehicle speed calculation unit for calculating the moving speed of the vehicle 23, the rotating body number calculation unit 17 as a rotating body number calculation unit for calculating the number of wheels of the vehicle 23, and the inter-axis distance of the vehicle 23 Since an inter-axis distance calculation unit 18 as an inter-axis distance calculation means to be calculated is added, and the other parts are the same, only differences from the first embodiment will be described.

  The speed information input unit 15 includes a microwave Doppler sensor similar to the speed information input unit 11 in the first embodiment. For example, as illustrated in FIGS. It is installed so as to face the side surface of the vehicle 23 traveling on the road. In that case, unlike the speed information input unit 11 in the first embodiment, the traveling direction of the vehicle 23 as shown in FIG. 14 is detected so that the speed in the traveling direction of the vehicle 23 is detected instead of the rotation of the wheels (tires). It is characterized by irradiating the side surface of the vehicle 23 with a microwave in a spot shape by disposing it obliquely (for example, θ = 45 degrees) when viewed from the upper surface toward a.

The vehicle speed calculation unit 16 converts the speed information of the vehicle 23 input by the speed information input unit 15 into an actual speed (v). For example, the vehicle speed calculation unit 16 obtains the calculation by the following equation 1 using a CPU or the like. be able to. When measured at an angle of θ as shown in FIG. 14, the speed of cos (θ) is generally detected when facing directly, so the original speed can be calculated by multiplying the inverse thereof.
v = v ′ / cos (θ) (Equation 1)
v ′: Detected speed Note that, when a strict speed is required, a slight correction may be required. For example, the correction count k is experimentally determined.
v = k × v ′ / cos (θ) (Equation 2)
It is also included in the scope of the present embodiment to calculate the speed using.

  First, the rotating body number calculation unit 17 creates a vehicle presence / absence signal from the speed information of the vehicle 23 calculated by the vehicle speed calculation unit 16 using a preset threshold value. Thereby, separation of vehicles becomes possible. Next, the number of wheels (tires) of one vehicle is counted by counting the number of wheels detected by the rotating body detection unit 13 between one vehicle.

  The inter-axis distance calculation unit 18 measures an inter-axis distance (distance between the axle center of the front wheel 26a and the axle center of the rear wheel 26b) L as shown in FIG. Can be realized. First, the time to the axle center of each of the front wheel 26a and the rear wheel 26b in the vehicle 23 is obtained from the significant speed information (wheel speed direction information) of FIG. Specifically, the central time of V = 0 is obtained.

Next, using the speed information of the vehicle 23 from the vehicle speed calculation unit 16, an inter-axis distance L is calculated by performing an operation as shown in Equation 3 below.
L = {(the center time of the front wheel 26a) − (the center time of the rear wheel 26b)} ×
(Speed of vehicle 23) (Equation 3)
Next, with the above configuration, the operation according to the second embodiment will be described with reference to the flowchart shown in FIG.
In the following description, as in the first embodiment, a case will be described in which the wheels 26 of the vehicle 23 traveling at the toll gate on the toll road are detected as shown in FIG.

  From step S1 to S3, the same operation as that of the first embodiment (FIG. 7) described above is performed.

  The speed information input unit (microwave Doppler sensor) 15 detects the speed information of the vehicle 23 and sends it to the vehicle speed calculation unit 16 (step S4). The vehicle speed calculation unit 16 converts the speed information of the vehicle 23 input by the speed information input unit 15 into the actual speed (v) corrected by performing the calculation of Formula 2, and is provided in the vehicle speed calculation unit 16. The data is stored in the RAM (step S5). This is schematically shown in FIG.

Next, the rotating body number calculation unit 17 creates a vehicle presence / absence signal V2 from the speed information v of the vehicle 23 calculated by the vehicle speed calculation unit 16 using a preset threshold value. That is, by comparing the speed information v with a predetermined threshold value (for example, 2 km / h) set in advance, the vehicle presence / absence signal V2 is “1” if the speed information v indicates a significant speed, and otherwise. The vehicle presence / absence signal V2 is set to “0” and stored in a RAM provided in the rotating body number calculation unit 17 (step S6). This is schematically shown in FIG. 18, and schematically shown in the graph as shown in FIG. Here, when V2 = 1, it is estimated that the vehicle 23 exists.
In FIG. 19, V3 indicates a wheel (rotary body) presence / absence signal (wheel presence / absence signal), which is superimposed on the significant speed information shown in FIG.

  Next, the rotating body number calculation unit 17 counts the number of wheels of one vehicle by counting the number of wheels detected by the rotating body detection unit 13 between one vehicle (step S7). ). That is, it is detected that there are two wheels (rotating bodies) in the vehicle presence signal of the vehicle presence / absence signal V2 shown in the graph of FIG.

Next, the inter-axis distance calculation unit 18 calculates the inter-axis distance L by performing the calculation of Equation 3 using the speed information of the vehicle 23 from the vehicle speed calculation unit 16 (step S8). That is, as described above, in the wheel speed direction information of FIG. 9, since it is recognized that there are wheels (tires) at addresses 18 to 40 and addresses 61 to 83, respectively, as shown in FIG. The center addresses (time) are 73 and 30, respectively, and are obtained as follows.
L = (73−30) × 10 (m / s) × 14000 / 3600≈1.68
Here, conversion of 14 (km / h) = 14000/3600 (m / s) was performed, and the unit was adjusted.

  In the above-described embodiment, the microwave Doppler sensor is used as the speed information input units 11 and 15. However, the present invention is not limited to this, and for example, a spatial filter type speedometer can be used.

  The spatial filter type speedometer uses a comb-shaped sensor to extract only a specific pattern from random reflection unevenness on the road surface, etc., and detects the speed with the change frequency. Therefore, although detailed description is omitted, the light emitting unit 31 and the light receiving unit 32 are configured as shown in FIGS.

  The light emitting unit 31 includes a cylindrical main body 33, a lamp 34 as a light source housed in the main body 33, a reflection mirror 35 that radiates light from the lamp 34 toward an object to be detected, and protection that protects the light emission port. A glass plate 36 is used.

  The light receiving unit 32 receives the reflected light from the cylindrical main body 37, the objective lens 38 accommodated in the main body 37, the light receiving slit plate 39, and the object to be detected via the objective lens 38 and the light receiving slit plate 39. It is composed of the element 40. The light receiving element 40 includes two comb-shaped sensors 40a and 40b.

  When the spatial filter type speedometer configured in this way is applied to the speed information input unit 11 of the first embodiment, as shown in FIGS. 23 and 24, the direction in which the speed of the traveling direction of the wheel 26 is measured is measured. When installed and applied to the speed information input unit 15 of the second embodiment, as shown in FIGS. 25 and 26, the vehicle 23 is arranged in the direction in which the speed in the traveling direction is measured. 23 to 26 are illustrated as being installed on the road 21, but are actually installed on the island 22.

An outline of the operation of the spatial filter type speedometer installed as the speed information input unit 11 will be described.
In the spatial filter type speedometer 11 arranged just beside the wheel 26, the light emitted from the light emitting unit 31 is reflected by the wheel 26 of the vehicle 23 as shown in FIG. 21, and the reflected light is received by the light receiving unit 32. The light receiving unit 32 includes two comb-shaped sensors 40a and 40b. By taking the difference between the outputs, only the reflection unevenness corresponding to the grating pitch (frequency) of the sensors 40a and 40b can be detected. Furthermore, the speed information of the wheel 26 can be obtained by signal processing the temporal change of the reflection unevenness.

  The operation of the spatial filter type speedometer installed as the speed information input unit 15 is substantially the same. In this case, the speed information of the vehicle 23 is detected.

  According to the moving rotating body detection apparatus of at least one embodiment described above, a speed information input unit (a microwave Doppler sensor or a spatial filter type speed is used to detect speed information for rotation of a wheel in a direction perpendicular to the road surface. By installing a meter, it is possible to detect the movement of the wheel in the rotational direction and detect the presence or absence of the wheel and the direction of movement. In addition, the presence or absence of the vehicle can be detected by detecting the moving speed of the vehicle, and the inter-axis distance can be obtained from the moving speed of the vehicle and the inter-wheel time of the wheels. Therefore, compared to the conventional tread board method and laser scanning method, it is possible to detect the wheel with high accuracy without contact and to calculate the wheel shaft distance, and it has a longer service life and can be applied to a vehicle traveling at high speed. The thing which was excellent also in the property is obtained.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and 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 equivalents thereof.

  DESCRIPTION OF SYMBOLS 11 ... Speed information input part (speed information acquisition means), 12 ... Speed information processing part (speed information processing means), 13 ... Rotating body detection part (rotating body detection means), 21 ... Road (moving path), 22 ... Island , 23 ... Vehicle (moving body), 26 ... Wheel (rotating body), 15 ... Speed information input section (speed information acquisition means), 16 ... Vehicle speed calculation section (vehicle speed calculation means), 17 ... Rotating body number calculation section (rotation) Body number calculation means), 18... Inter-axis distance calculation unit (inter-axis distance calculation means).

Claims (9)

Speed information acquisition means provided at a side portion of a moving path along which a moving body having a rotating body moves, acquires speed information for rotation of the rotating body in a direction perpendicular to the surface of the moving path;
Based on the speed information acquired by the speed information acquiring means, a rotating body detecting means for detecting the rotating body by performing a detection process of a speed pattern that can be recognized as a rotating body;
A moving rotator detection apparatus comprising: Speed information acquisition means provided on a side portion of a road on which the vehicle travels, and acquires speed information for rotation of a wheel of the vehicle in a direction perpendicular to the surface of the road;
Based on the speed information acquired by the speed information acquisition means, a rotating body detection means for detecting the wheel by performing a speed pattern detection process that can be recognized as a wheel,
A moving rotator detection apparatus comprising: Further comprising speed information processing means for converting the speed information acquired by the speed information acquisition means into significant speed information by comparing with a preset threshold value;
The said rotating body detection means detects the said wheel by performing the detection process of the speed pattern which can be recognized as a wheel based on the significant speed information converted by the said speed information processing means. Moving rotor detection device.   3. The moving rotator detection apparatus according to claim 1, wherein the speed information acquisition means is configured by a microwave Doppler sensor or a spatial filter type speedometer that detects a speed by a Doppler effect. A moving body having at least two or more rotating bodies arranged side by side in the moving direction of the moving body is provided on a side portion of the moving path along which the moving body moves, and the rotating body is in a direction perpendicular to the surface of the moving path. First speed information acquisition means for acquiring speed information;
Rotating body detecting means for detecting the rotating body by performing a speed pattern detection process that can be recognized as a rotating body based on the speed information of the rotating body acquired by the first speed information acquiring means;
Second speed information acquisition means provided on a side portion of the moving path, for acquiring speed information indicating a moving speed of a moving body moving on the moving path;
The moving body presence / absence signal is created from the speed information of the moving body acquired by the second speed information acquisition means, and detected by the rotating body detection means in the presence signal in the created moving body presence / absence signal. Rotating body number calculating means for counting the number of the rotating bodies that have been
A moving rotator detection apparatus comprising: Provided on the side portion of the road on which the vehicle having at least two or more wheels arranged in the running direction of the vehicle on the side portion travels, and obtains speed information regarding the rotation of the wheels of the vehicle in the direction perpendicular to the surface of the road First speed information acquisition means for
Based on the speed information of the wheel acquired by the first speed information acquisition means, a rotating body detection means for detecting the wheel by performing a speed pattern detection process that can be recognized as a wheel;
A second speed information acquisition means provided on a side of the road for acquiring speed information indicating a traveling speed of a vehicle traveling on the road;
The vehicle presence / absence signal is created from the vehicle speed information acquired by the second speed information acquisition means, and the wheel detected by the rotating body detection means within the presence signal in the created vehicle presence / absence signal Rotating body number calculating means for counting the number of
A moving rotator detection apparatus comprising: A speed information processing means for converting the speed information acquired by the first speed information acquisition means into significant speed information by comparing with a preset threshold value;
The rotating body detection means detects the wheel by performing a speed pattern detection process that can be recognized as a wheel based on significant speed information converted by the first speed information processing means. Item 7. The moving rotating body detection device according to Item 6.   The inter-axis time of each wheel detected by the rotating body detecting means is obtained, and the inter-axis distance of each wheel is determined from the obtained inter-axis time and the vehicle speed information obtained by the second speed information obtaining means. 7. The moving rotator detection apparatus according to claim 6, further comprising an inter-axis distance calculation means for calculating   The first speed information acquisition unit or the second speed information acquisition unit is configured by a microwave Doppler sensor or a spatial filter type speedometer that detects a speed by a Doppler effect. The moving rotating body detection apparatus according to claim 6.

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