JP2019133241A - Vehicle detection device and vehicle detection system - Google Patents

Abstract

To provide a vehicle detection device capable of accurately detecting that a towing vehicle is integrated with an object to be towed when the vehicle towing the object to be towed passes.SOLUTION: A vehicle detection device 1 erected on one side of a lane through which a vehicle 2 passes is provided with a laser scanner covering a main part in the plane almost perpendicular to a traveling direction of the vehicle 2. When the vehicle 2 provided at the rear of a pseudo-connection part 5 simulating a connection body for towing an object to be towed passes through a scanning surface, the connection body detection area δ that is a region through which the pseudo-connection part 5 is likely to pass is preliminarily set, and a connection body detectable condition including a scanning frequency and an angular resolution determined according to an allowable upper limit speed of the vehicle 2 and an assumed shape of the connection body is set so that the pseudo-connection part 5 can be detected at one or more places in this connection body detection area δ, thereby detecting the presence or absence of the connection body from point group data obtained by operating the laser scanner so as to satisfy the connection body detectable condition.SELECTED DRAWING: Figure 10

Description

  The present invention relates to a vehicle detector that detects from entry to passage of a vehicle at a toll collection or parking lot on a toll road, and a vehicle that provides significant information obtained by processing detection information from the vehicle detector to an upper station. It relates to a detection system.

  An ETC system that collects tolls by mounting a vehicle-mounted device as a mobile station on a mobile vehicle and exchanging data via a roadside radio device as a base station installed on a toll road (Toll road automatic toll collection system) is used. In the operation of the ETC system, it is very important to be able to perform smooth transmission and reception between the vehicle terminal device and the roadside wireless device, and vehicle entry detection to the ETC lane, which is the start timing of toll collection processing, and toll collection is over A vehicle detector is used for detecting the passing of a vehicle.

  In current ETC toll collection stations, transmission type vehicle detectors in which a light emitting device and a light receiving device are arranged opposite to each other on both sides of a road are used (see, for example, Patent Document 1). This is based on whether or not the detection light emitted from the light emitting device issuer group is detected by the light receiving device group of the light receiving device, and whether there is a vehicle between the light emitting device and the light receiving device (presence of an obstacle). Is detected. That is, it can be determined that the vehicle has entered when the vehicle is changed from the state without the vehicle, and conversely, when the vehicle is changed from the state with the vehicle to the state without the vehicle, it can be determined that the vehicle has passed.

  Such a transmission type vehicle detector has a vehicle entry detection point for radio wave emission timing determination at the start of toll collection processing, a vehicle passage detection point for communication completion determination at the end of toll collection processing, and a bar at the toll gate exit. It is necessary to provide each at a vehicle entry / passage detection location for opening / closing timing determination. That is, since a combination of a light emitting device and a light receiving device must be introduced at each detection location, the overall cost becomes high. In addition, when the light emitting device and the light receiving device are arranged at each location on the island, there is a problem that visibility from the toll booth is impaired.

  There is also a vehicle detection method that does not use the transmission type vehicle detector described above. For example, by providing a laser sensor on the beam part of the overpass structure (gantry) provided to straddle multiple routes, scanning the road surface from above so as to be orthogonal to the vehicle traveling direction, the unevenness of the road surface is detected, A traffic detection system that detects protrusions from the road surface as a passing vehicle has been proposed (see, for example, Patent Document 2).

  According to the traffic detection system described in Patent Document 2, a large number of combinations of light emitting devices and light receiving devices are not required unlike a transmission type vehicle detector, and visibility from a toll booth is not impaired.

JP2015-125023 A JP 2013-190898 A

  However, in the traffic detection system described in Patent Document 2, a laser sensor provided on a beam portion (approximately 4 to 5 m high) of the gantry that is higher than the top of the large vehicle is used. The detection accuracy in the vicinity of the road surface that is a long distance from the installation location is lowered, and there is a problem that proper vehicle detection cannot be performed.

  For example, when a vehicle towing a towed object such as a loading trailer or a cargo trailer passes, the connecting body that connects the vehicle and the towed object is at a height of about several tens of centimeters to 1 meter from the road surface. In order to detect with a laser sensor provided in the beam part of the gantry, a laser sensor with a very high angular resolution must be used. However, the laser sensor used in the traffic detection system described in the cited document 2 has an angular resolution necessary and sufficient to determine the presence or absence of a relatively large vehicle body by scanning from the beam part of the gantry toward the road surface. Therefore, the detection performance capable of reliably detecting the connected body is not assumed. Moreover, if the scanning period of the laser sensor is not set sufficiently short with respect to the traveling speed of the vehicle traveling on the highway, it is not possible to reliably detect a relatively short connector in the vehicle traveling direction.

  In this way, if the angular resolution and scan frequency of the laser sensor do not satisfy the condition for detecting the connected object, the connected object that connects the towed vehicle and the towed object cannot be detected, and there is no non-connection between the towed vehicle and the towed object. There is a possibility that detection spaces are generated and these are detected as separate vehicles. However, the laser scanner installed at a high position 4 to 5m away from the road surface of the expressway is one that can achieve detection accuracy of several centimeters or less near the road surface because of cost, equipment size and weight. Not at all realistic.

  Moreover, in the traffic detection system described in Patent Document 2, a first vehicle detection area and a second vehicle detection area are formed at a distance D in the vehicle traveling direction, and the second vehicle detection area is connected to the second vehicle detection area. The vehicle speed V is estimated from the vehicle passage time to the vehicle detection area and the distance D, and the vehicle length L is estimated from the vehicle speed V and the vehicle passage time. From the vehicle length L, the vehicle type (light vehicle, ordinary vehicle, medium size vehicle) is estimated. Vehicle types such as large vehicles, oversized vehicles). However, if a connecting body that connects the vehicle and the towed object cannot be detected, it is estimated that the towed vehicle and the towed object are different passing vehicles, and therefore, appropriate vehicle detection cannot be expected from this point.

  Therefore, the present invention is based on a vehicle detector that can accurately detect that the towed vehicle and the towed object are integrated when the vehicle towing the towed object passes, and detection information from the vehicle detector. An object of the present invention is to provide a vehicle detection system that can process significant information of passing vehicles.

  In order to solve the above-mentioned problem, the invention according to claim 1 is a housing installed on one side of a vehicle passage area through which a vehicle can pass, and a laser housed in the housing and irradiated from a light transmitting / receiving unit. Detection in which the scanning range that can scan and detect the two-dimensional surface with light is set in a plane that intersects the traveling direction of the vehicle, and the reflected light from the laser beam reflector within the scanning range is detected by the light transmitting and receiving unit A laser scanner that acquires point cloud data consisting of points for each scanning period, and an optical path protection unit that is formed in the housing and does not obstruct the optical paths of the irradiation light and the reflected light in the scanning range of the laser scanner, Within the scanning range of the scanner, a connected body detection area is set in advance as an area where a connected body that connects the towed object to the vehicle is likely to pass, and the vehicle passes When a connecting body is provided in a vehicle that passes through a zone, it is determined according to the allowable upper limit speed of the vehicle and the assumed shape of the connecting body so that the connecting body can be detected at one or more places in the connecting body detection area. The laser scanner is operated under the condition that the connected body can be detected including the scanning frequency and the angular resolution.

  According to a second aspect of the present invention, in the vehicle detector according to the first aspect of the present invention, there is no obstacle in which no obstacle is detected in a detection space where no obstacle can be detected at all times within the scanning range of the laser scanner. A vehicle approach detection signal is output at a timing when the detection state changes to an obstacle detection state in which an obstacle is detected in the detection space.

  According to a third aspect of the present invention, in the vehicle detector according to the first or second aspect, the obstacle is detected in a detection space where the obstacle cannot be detected at all times within the scanning range of the laser scanner. A vehicle passage detection signal is output at a timing when the obstacle detection state changes to an obstacle non-detection state where no obstacle is detected in the detection space.

  According to a fourth aspect of the present invention, in the vehicle detector according to any one of the first to third aspects, the housing includes a cylindrical portion that extends in a direction perpendicular to the installation surface, It comprises a hemispherical apex that is continuous with the circular upper edge of the cylindrical part, and is provided with a scan guide concave part that faces the transmitting / receiving part of the laser scanner in a concave chamber structure that is recessed from an appropriate place on the peripheral surface of the cylindrical part.

  According to a fifth aspect of the present invention, in the vehicle detector according to any one of the first to fourth aspects, the light transmitting / receiving portion of the laser scanner splashes mud from the vicinity of the vehicle passing area. It is characterized in that it is provided at a position higher than a predetermined contamination warning range as a range in which there is a high possibility of being attached and contaminated.

  In order to solve the above-mentioned problem, an invention according to claim 6 receives the vehicle detector according to any one of claims 1 to 5 and point cloud data from the vehicle detector. A vehicle detection system comprising: a processing device that performs processing, wherein the processing device arranges the point cloud data in time series to generate a 3D image, specifies a passing vehicle type, and connects the 3D images. When a body is detected, it is determined that one vehicle has passed including the front and rear of the connected body.

  According to the vehicle detector according to the present invention, the to-be-towed object is pulled because the scanning by the laser scanner operated under the condition that the connected body can be detected is performed from one side of the vehicle-passing area to the vehicle-passing area. If the vehicle passes through the vehicle passage area at an allowable upper limit speed or less, the connected body can be accurately detected in the connected body detection area. Therefore, the malfunction which erroneously detects the tow vehicle and to-be-towed object connected with the coupling body as another vehicle can be suppressed.

  Further, according to the vehicle detection system of the present invention, the processing device arranges the point cloud data from the vehicle detector in time series to generate a 3D image, specifies the passing vehicle type, and connects with the 3D image. When a body is detected, it is determined that one vehicle has passed including the front and back of the connected body, so that the problem of erroneously detecting the tow vehicle and the to-be-towed object connected by the connected body as another vehicle is suppressed. it can.

Embodiment of the vehicle detector which concerns on this invention is shown, (a) is a front view of a vehicle detector, (b) is a side view of a vehicle detector. It is explanatory drawing in the case of detecting a to-be-detected body with the laser beam irradiated for every step angle from the laser scanner. It is an external appearance perspective view of the state which attached the pseudo | simulation connection part which consists of a 1st connection body-a 5th connection body to the vehicle rear part with a vehicle body fixing tool. It is a top view of the state which attached the pseudo | simulation connection part to the vehicle rear part with the vehicle body fixing tool. (A) is a side view of the state which attached the pseudo | simulation connection part to the vehicle rear part with the vehicle body fixing tool. (B) is an expanded side view of a to-be-towed body and a pseudo | simulated connection part. (C) is a longitudinal end view of the first to fifth connectors. It is a comparison figure with the measurement result and the calculation result which scanned the pseudo | simulation connection part on various conditions with the laser scanner installed in the height of 2.5 m. It is a comparison figure with the measurement result and the calculation result which scanned the pseudo | simulation connection part on various conditions with the laser scanner installed in the height of 1.5 m. It is a comparison figure of the measurement result and the calculation result which scanned the pseudo | simulation connection part on various conditions with the laser scanner installed in the height of 1.0 m. It is a characteristic view of the vehicle speed-vehicle advancing direction resolution | decomposability of the actual measurement result and the calculation result which scanned the traveling vehicle with various conditions with the laser scanner. It is explanatory drawing of the connection body detection area set in the scanning range (alpha) of the vehicle detector installed in the ETC lane. It is explanatory drawing about the example of 1 installation in the case of operating the vehicle detector which concerns on this embodiment in an ETC lane. It is explanatory drawing of the scanning range (alpha) and undetectable area | region in the toll type vehicle detector installed in the ETC lane. It is a schematic block diagram of the vehicle detection system which consists of a vehicle detector and the processing apparatus which receives and processes the point cloud data from this vehicle detector. The 3D image of the passing vehicle produced | generated from the point cloud data is shown, (a) is an overhead perspective view from the front, and (b) is a side view.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a vehicle detector according to the present invention will be described in detail with reference to the accompanying drawings. Note that the vehicle detector 1 according to the present invention is not limited to an automobile, and can detect entry and passage of a moving vehicle (for example, a railway vehicle) that passes through a detection area. However, it is necessary to appropriately set a connected body detection area (detailed later) and a connected body detectable condition (detailed later) according to the vehicle to be detected.

  The vehicle detector 1 shown in FIG. 1 is installed on one side of a vehicle passage area such as a road through which a car 2 passes and a parking lot entrance / exit (for example, an island provided between lanes in a toll gate) A vehicle passing through the vehicle passage area can be detected by one vehicle. For this reason, the laser beam LB is applied to a suitable position (for example, near the top) of the vehicle detector 1 at a step angle within a plane that intersects the traveling direction of the automobile 2 (substantially orthogonal in the present embodiment). A laser scanner 12 that can be scanned in a fan-shaped scan range α is stored.

  When this laser scanner 12 receives the reflected light that has been reflected and returned from the surface of the automobile 2 or the like, the irradiation direction of the laser light LB at that time and the flight time of the laser light LB (irradiate a laser pulse with a projector to receive light). From the elapsed time until the reflected light is detected by the instrument, the coordinates of the detection point on the scan plane can be specified. That is, the vehicle detector 1 can acquire point cloud data composed of detection points of the automobile 2 in the scan range on the laser light irradiation plane for each scan cycle, and the point cloud data for each cycle corresponds to the scan cycle. If the movement distance of the automobile 2 is shifted and plotted on the space, it becomes three-dimensional point cloud data. Therefore, by smoothing the surface of the three-dimensional point cloud data, the 3D image of the automobile 2 that is the object to be detected. (An image of a surface that can be irradiated with the laser beam LB without obstruction) can be easily reproduced.

  The laser scanner 12 itself has a scanning angle exceeding 180 [°] (for example, 190 [°]), but for vehicle detection, the vehicle 2 in the vehicle passing area from the position where the laser scanner 12 is installed. An angle range necessary and sufficient for scanning (for example, scan range α = elevation angle 73 [°] + depression angle 73 [°] = 146 [°]) may be used. Further, when the vehicle 2 that is running is scanned by the vehicle detector 1, since the vehicle 2 is also moved according to the running speed between the scan start time and the scan end time, the obtained point cloud data is The position of the point cloud data acquisition position is not negligible when the vehicle 2 has a high traveling speed and is positioned on a plane that is obliquely rearward of the original scan plane. However, if the deviation of the acquired point cloud data is corrected using the traveling speed of the automobile 2 at the time of scanning, distortion of the generated 3D image can be suppressed.

  Further, as a vehicle detection function, the laser scanner 12 detects an obstacle in the detection space from an obstacle non-detection state in which no obstacle is detected in the detection space where the obstacle cannot be detected at all times within the scan range α. A function of outputting a vehicle entry detection signal (for example, a single pulse trigger signal) at the timing when the object detection state is changed is provided. By using this vehicle entry detection signal, it is possible to quickly know the timing at which the vehicle has entered the detection area, so that it can be used to determine the start timing of the ETC communication or the gate opening timing. Contrary to this, the obstacle non-detection state in which the obstacle is no longer detected in the detection space from the obstacle detection state in which the obstacle is detected in the detection space where the obstacle cannot be detected at all times within the scan range α. The laser scanner 12 also has a function of outputting a vehicle passage detection signal (for example, a single pulse trigger signal) at the timing changed to. By using this vehicle passage detection signal, it is possible to quickly know the timing at which the vehicle has passed through the detection area, so that it can be used to determine the end timing of the ETC communication or the gate closing timing.

  That is, if the vehicle detector 1 is provided only on the island on one side with respect to the lane of the ETC lane, the entry and passage of the automobile 2 can be detected, so a pair of vehicle detectors are arranged for each necessary vehicle detection position. This is not necessary, and has the advantage that the visibility from the toll booth is not easily lost, in addition to simplifying the installation work and reducing the installation cost.

  The housing 11 for housing the laser scanner 12 has a cylindrical portion 11a having a smooth outer peripheral surface (for example, a diameter of the outer surface of the cylinder of about 275 [mm]) and a circular upper edge of the cylindrical portion 11a. It consists of a series of smooth hemispherical hemispherical top portions 11b and an installation body 11c fixed on an island (for example, a height of 250 [mm]) beside the ETC lane. When the installation body 11c of the housing 11 is erected on an island installed in parallel with the roadway, the cylindrical portion 11a of the housing 11 extends in a direction perpendicular to the installation surface (or a vertical direction if the road surface of the lane is horizontal). Therefore, the laser scanner 12 housed in the housing 11 (for example, the center of the light transmitting / receiving unit 12a of the laser scanner 12 is disposed at a height of about 1 [m] from the base of the installation body 11c) It is installed at a position (for example, 1250 [mm]) higher than the road surface by the height of the island.

  The installation body 11c is an outer diameter cylindrical body that can be fitted into the lower opening of the cylindrical portion 11a, and an annular convex portion 11c3 is formed between the fixed portion 11c1 and the fitted insertion portion 11c2. Thus, when the lower opening of the cylindrical portion 11a is fitted into the fitting insertion portion 11c2 of the installation body 11c, the lower edge of the cylindrical portion 11a is positioned just at the annular convex portion 11c3, and the housing 11 is moved to a predetermined height (for example, 1 .5 [m] high height). Note that the installation body 11c may be fitted into the cylindrical portion 11a so that the installation body 11c is not fixed in place, and an appropriate fixing structure may be provided below the cylindrical portion 11a.

  Further, the vehicle detector 1 of the present embodiment includes a relatively small secondary laser scanner 13, and the secondary laser scanner 13 is substantially parallel to a plane orthogonal to the detection surface of the laser scanner 12, that is, a road surface. It can perform scanning on the detection surface. When the sub laser scanner 13 detects a moving body within the scan range, the speed of the moving body can be obtained from the amount of movement of the moving body detected for each scan cycle. Note that the speed of the moving body can be detected using a known existing speed detection device, so the sub laser scanner 13 may not be used for speed detection of the moving body.

  The laser scanner 12 and the auxiliary laser scanner 13 described above are arranged in a scan guide recess 14 as an optical path protection unit. The scan guide recess 14 has a concave chamber structure that is recessed inward from an appropriate position on the cylindrical surface 11 a of the housing 11. Make the light receiving part face the vehicle detection space.

  The scan guide recess 14 as the optical path protection unit has a vertically long opening surface (for example, a height of about 708 [mm] and a width of at least, which can secure at least the irradiation range of the laser beam LB by the laser scanner 12 and the reception range of the reflected light). An opening surface of about 95 [mm] is provided on the peripheral surface of the cylindrical portion 11a, and is a concave chamber that is recessed from the opening surface into the cylindrical portion 11a. Specifically, the first side wall part 14a and the second side wall part 14b arranged on the back side from the left and right side edges of the vertically long slit-shaped opening surface opened in the cylindrical part 11a, the first and second side wall parts 14a, 14b, four side walls comprising an upper wall portion 14c continuous with the upper edge of the lower wall portion 14b and a lower wall portion 14d continuous with the lower edge of the first and second side wall portions 14a, 14b, and rear edge openings of the side wall portions 14a to 14d. Is closed by the upper back wall portion 14e and the lower back wall portion 14f. Note that the light transmission / reception unit 12a of the laser scanner 12 faces the gap formed between the upper back wall portion 14e and the lower back wall portion 14f.

  In the back of the scan guide recess 14, the upper back wall portion 14 e that closes the upper side of the laser scanner 12 includes an opening / closing lid 14 e 1 that accesses an operation panel for device setting and the operation state and setting state of the vehicle detector 1. A pilot lamp group 14e2 for display is provided. Further, the lower back wall portion 14f that closes the lower side of the laser scanner 12 is connected to the lower portion of the laser scanner 12 and the lower edge of the flat plate portion 14f1, and gradually protrudes forward. It consists of a tapered flange portion 14f2 and a second flat plate portion 14f3 connected to the lower rear edge of the flange portion 14f2 and the lower wall portion 14d. In addition, the upper part of the sub laser scanner 13 can be protected from rain and dust by disposing the flange part 14f2 of the lower back wall part 14f so as to cover the sub laser scanner 13.

  In this way, by allowing the light transmitting / receiving unit 12a of the laser scanner 21 and the light transmitting / receiving unit of the sub laser scanner 13 to scan within the scan guide recess 14 of the housing 11, the laser scanner 12 and the sub laser scanner 13 are accommodated in the housing 11. Therefore, it is possible to effectively prevent flying objects and the like from hitting the laser scanner 12 and the auxiliary laser scanner 13 and damaging them. In addition, since the outer surface of the housing 11 is formed with a generally smooth curved surface except for the scan guide recess 14, there is a low risk of injury even if touched by a person. Further, since the hemispherical top portion 11b of the housing 11 is a smooth hemispherical surface, it is difficult to accumulate snow and fallen leaves and the like, and it is possible to reduce the trouble of snow removal and cleaning. In addition, since the opening surface of the scan guide recess 14 is formed in a vertically long slit shape, it is difficult for wind and snow to blow in, and effectively avoids a situation in which scanning cannot be performed because the transmitter / receiver 12a is blocked by dust or snow. it can. Furthermore, providing a snow melting heater that heats the appropriate position of the scan guide recess 14 is more effective in avoiding inability to scan due to snowfall.

  In addition, a translucent window portion (a shield formed of a hard material transparent to the wavelength of the laser light to be used) that closes the opening surface of the scan guide recess 14 provided in the housing 11 is provided, and the cylindrical portion 11a is provided. If a complete cylindrical body isolated from the inner space is used, the internal devices such as the laser scanner 12 are protected, so that it is not necessary to provide the scan guide recess 14. However, in that case, it is necessary that the emission intensity of the laser beam LB that has passed through the transmissive window is maintained at a specified value or higher, and the reflected light from the detection target is incident on the transmissive window at a transmittance greater than the specified value. Sufficient detection function needs to be maintained. In addition, it is necessary to correct the detection position in consideration of the refraction of the laser beam LB generated when the light passes through the transmissive window.

  Further, the island where the vehicle detector 1 is installed has a risk of being covered with muddy water when the automobile 2 passes through a puddle formed on the road due to rain, snow, etc., and the laser scanner provided in the vehicle detector 1 If the 12 light transmitting / receiving units 12a and the light transmitting / receiving unit of the sub laser scanner 13 are soiled by mud splashing or the like and the transmission of the laser beam LB is inhibited, proper vehicle detection cannot be performed. Accordingly, the contamination warning range set in advance as a range in which mud splashes and the like from the vicinity of the vehicle passing region are highly likely to be contaminated by the light transmission / reception unit 12a of the laser scanner 12 and the sub laser scanner 13 It is set to be higher than β (see FIG. 1B). In this way, even if the muddy water jumps to the installation side of the vehicle detector 1 because the tire of the automobile 2 passes through the puddle, the transmission / reception unit 12a of the laser scanner 12 positioned higher than the contamination warning range, The possibility that the light transmitting / receiving unit of the sub laser scanner 13 is soiled is extremely low, and the vehicle detection function of the vehicle detector 1 can be maintained well.

  Next, the obstacle detection function of the laser scanner 12 used in the vehicle detector 1 will be described. FIG. 2 shows a state in which, when the first to fifth detection objects 3a to 3e are arranged within the scan range of the laser scanner 12, they are detected by the laser light LB emitted from the laser scanner 12. The first to fifth detected bodies 3a to 3e have a bottom surface that is substantially parallel to the road surface, two upper surfaces that are perpendicular to the road surface (for example, a side closer to the laser scanner 12 is a first side surface, and the opposite is a second side surface. A rectangular parallelepiped with side surfaces). The step angle for irradiating the laser beam LB from the laser scanner 12 can be set to 0.2 [°] or less depending on the scan frequency, but here, the step angle is so rough that the irradiation interval of the laser beam LB is visible. It is shown.

  The first detected object 3a, which is approximately the same height as the installation height (for example, 2.5 [m]) of the laser scanner 12 and separated by about 2 to 2.5 [m], has laser light on the first side surface. Three irradiation points of LB are generated. Since these three points (shown by black circles in FIG. 2) are all within 45 ° of the incident angle of the laser beam LB, the reflected light reflected at these three irradiation points returns to the light transmitting / receiving unit 12a of the laser scanner 12. There is a high possibility of receiving light. Therefore, the number of sampling points at which the first detected object 3a is detected by the laser scanner 12 is three points. Strictly speaking, since the beam width (spot size) changes depending on the irradiation distance of the laser beam LB, even if the beam center does not hit the object to be detected, a part of the laser beam deviating from the beam center is calculated. Although there is a possibility that the object is irradiated, the reflected light in such a case is not likely to be returned to the laser scanner 12 as a detectable amount of light, so the beam center is hit here. Items that are not exposed are excluded as irradiation points. The same applies to the following.

  The second detected body 3b arranged just above the first detected body 3a (for example, 3.5 [m]) has four irradiation points of the laser beam LB on the bottom surface. Of these, the rear three points (indicated by white circles in FIG. 2) all have an incident angle of the laser beam LB exceeding 45 °, so that the reflected light reflected at these three irradiation points is transmitted to the laser scanner 12. Although there is almost no possibility of receiving light back, only the first point (indicated by a black circle in FIG. 2) has an incident angle of the laser beam LB within 45 °. There is a high possibility that light will be returned to the scanner 12. Therefore, the sampling point on the bottom surface of the second detected body 3b is one point. On the other hand, two irradiation points of the laser beam LB are also generated on the first side surface of the second detected body 3b. Since these two points (indicated by black circles in FIG. 2) both have an incident angle of the laser beam LB within 45 °, the reflected light reflected at these two irradiation points may be returned to the laser scanner 12 and received. Is expensive. Therefore, the sampling point at which the second detected body 3b is detected by the laser scanner 12 is 3 points in total including the bottom surface and the first side surface.

  A third detected object arranged at a slightly higher position (for example, 3.0 [m]) behind the first detected object 3a as appropriate (the separation distance from the laser scanner 12 is about 4 to 4.5 [m]). The body 3c has one irradiation point of the laser beam LB on the bottom surface. At this one point (indicated by a white circle in FIG. 2), since the incident angle of the laser beam LB exceeds 45 °, there is a possibility that the reflected light reflected at this irradiation point returns to the laser scanner 12 and is received. Almost no. Therefore, there is no sampling point on the bottom surface of the third detected body 3c. On the other hand, two irradiation points of the laser beam LB are also generated on the first side surface of the third detected body 3c. Since these two points (indicated by black circles in FIG. 2) both have an incident angle of the laser beam LB within 45 °, the reflected light reflected at these two irradiation points may be returned to the laser scanner 12 and received. Is expensive. Therefore, the number of sampling points at which the third detected object 3c is detected by the laser scanner 12 is two points.

  The fourth detected body 3d arranged immediately below the third detected body 3c (for example, 1.7 [m]) has two irradiation points of the laser beam LB on the first side surface. Since these two points (indicated by black circles in FIG. 2) both have an incident angle of the laser beam LB within 45 °, the reflected light reflected at these two irradiation points may be returned to the laser scanner 12 and received. Is expensive. Therefore, the sampling points at which the fourth detected body 3d is detected by the laser scanner 12 are two points.

  The fifth detected body 3e arranged in the vicinity of the laser scanner 12 (the horizontal separation distance is about 0.6 [m] and the installation height is about 1.5 [m]) has the laser beam LB on the first side surface. Three irradiation points are generated. Since these three points (indicated by white circles in FIG. 2) all have an incident angle of the laser beam LB exceeding 45 °, the reflected light reflected at these three irradiation points returns to the laser scanner 12 and is received. There is almost no possibility. Therefore, there is no sampling point on the first side surface of the fifth detected body 3e. On the other hand, 12 irradiation points of the laser beam LB are also generated on the upper surface of the fifth detected body 3e. Of these twelve points, eight points (indicated by black circles in FIG. 2) close to the first side face have an incident angle of the laser beam LB within 45 °, so that the reflected light reflected at these eight irradiation points is transmitted to the laser scanner 12. There is a high possibility of receiving light back. However, since the incident angle of the laser beam LB exceeds 45 ° at the four points (indicated by white circles in FIG. 2) behind it (side closer to the second side surface), the reflection reflected at these four irradiation points. There is almost no possibility that the light returns to the laser scanner 12 and is received. Therefore, the sampling points at which the fifth detected body 3e is detected by the laser scanner 12 are 8 points.

  As described above, when the automobile 2 is detected by the laser scanner 12 as the detection target, the coordinates of the irradiation point can be acquired only at the point where the laser beam LB from the laser scanner 12 is irradiated within an incident angle of 45 °. Since the side surface of the automobile 2 facing the vehicle detector 1 has a large area facing the laser scanner 2, relatively large point cloud data can be obtained. Therefore, the side surface of the automobile 2 can be converted into 3D data including some irregularities from the point cloud data. In addition, when the installation position of the laser scanner 12 is higher than the hood or roof, the surface of the hood or roof is also obtained as point cloud data, so that the depth in the width direction of the automobile 2 can be converted into 3D data.

  However, in the case of a vehicle that pulls a towed object such as a loading trailer or a cargo trailer, the connecting body that connects the towed vehicle and the towed object is composed of a bar or a square having a diameter of about 15 to 40 [mm], Since the height is at most about 300 to 700 [mm] from the road surface, the connected body cannot be reliably detected unless scanning conditions are set so that the sampling point of the connected body is 1 point or more. Further, even if the angular resolution of the laser scanner 12 is necessary and sufficient, if the scan frequency is low with respect to the traveling speed of the automobile 2, it will be about 500 [mm] before the next scan timing when the tow vehicle is last scanned. There is a possibility that a subsequent to-be-drawn object is scanned after passing through a non-detection space of 500 [mm] or longer in which the connecting body of the length passes and the connecting body cannot be scanned. In such a case, since there is an appropriate detected space between the tow vehicle and the towed object, there is a concern that the towed vehicle and the towed object may be mistaken for different vehicles.

  As described above, when detecting the vehicle towing the towed object with the laser scanner 12, it is necessary to prepare appropriate conditions for reliably detecting the connecting body that connects the vehicle and the towed object. is there.

  Therefore, based on the characteristics of the laser scanner 12, consider a scanning condition that can detect a connected body. If the angular resolution of the laser scanner 12 is high, it is possible to obtain one or more sampling points from a small connected body at a far distance. Further, if the scan frequency is high, the sampling point can be obtained from the connected body having a short length in the vehicle traveling direction even if the speed of the automobile 2 is high. However, in general, the laser scanner 12 has an inversely proportional relationship between the light receiving speed of reflected light and the angular resolution. Therefore, it is realistic to lower the scanning frequency to increase the angular resolution, or to lower the angular resolution to increase the scanning frequency. Judgment is necessary. That is, the scan frequency and the angular resolution determined according to the allowable upper limit speed of the vehicle and the assumed shape of the coupled body are set in advance as the coupled body detectable condition so that the coupled body can be detected. If the laser scanner 12 with sufficient performance is mounted, the vehicle detector 1 that can reliably detect the connected body can be configured.

  In order to search for the above-described connected body detectable condition, as shown in FIG. 3 to FIG. Install. And if it is tested whether the vehicle detector 1 to which the towed body 6 is pulled through the pseudo-connecting part 5 is scanned by the vehicle detector 1 under various conditions and the pseudo-connecting part 5 can be detected. It is possible to narrow down the conditions for detecting the connected body. 3 to 5, only the rear part of the vehicle 2 is shown.

  The vehicle body fixture 4 is provided at a connecting body mounting portion 41 disposed vertically in the rear center of the vehicle, a roof-side fixing portion 42 provided above the connecting body mounting portion 41, and a lower portion of the connecting body mounting portion 41. The vehicle bottom side fixing portion 43 is a structure in which long steel materials are combined. And the pseudo | simulation connection part 5 is attached so that it may extend to the back side from the downward part of the connection body attachment part 41 in the vehicle body fixing | fixed part 4, and the to-be-to-be-towed body 6 is attached to the rear part of the pseudo | simulation connection part 5. In order to increase the holding strength of the towed body 6, a beam member 44 that directly connects the connecting body mounting portion 41 and the towed body 6 is provided. Since the beam member 44 is positioned above the pseudo-connecting portion 5 within the scanning range of the vehicle detector 1, the beam member 44 detected by the vehicle detector 1 is regarded as a part of the pseudo-connecting portion 5. Be careful not to misunderstand.

  The quasi-connecting portion 5 is composed of five types of long rectangular frames having the same horizontal width but different vertical widths. Specifically, the first connecting body 51 (vertical width × horizontal width × length: 40 [mm] × 50 [mm] × 660 [mm]) is provided at the top, and the second connecting body 52 (vertical width) is provided therebelow. X width x length: 30 [mm] x 50 [mm] x 660 [mm]), and a third connector 53 (vertical width x width x length: 20 [mm] x 50 [mm] x) 660 [mm]) below the fourth connector 54 (vertical width × horizontal width × length: 15 [mm] × 50 [mm] × 660 [mm]), and below the fifth connector 54 ( Vertical width × horizontal width × length: 10 [mm] × 50 [mm] × 660 [mm]) are sequentially attached.

  When the lowermost part (the lower surface of the fifth connecting body 55) of the pseudo connecting part 5 configured as described above is attached to the automobile 2 so as to have a height of 315 [mm] from the road surface, the upper surface of the first connecting body 51 is approximately about the road surface. The height of the second connecting body 52 is about 635 [mm] from the road surface, and the upper surface of the third connecting body 53 is about 530 [mm] from the road surface. The upper surface of the fourth connecting body 54 is about 427.5 [mm] from the road surface, and the upper surface of the fifth connecting body 55 is about 325 [mm] from the road surface.

  There is no clear definition or legal restriction on the connecting body that connects the towed vehicle and the towed object, but the existing structure of the connecting body that is assumed to be general is 350 [mm] to 500 [mm] above the road surface. It is assumed that the cross section of the coupling body is set to 15 [mm] × 50 [mm] or more so as to withstand the weight load of the towed object. Since it is the 4th connection body 54 in the pseudo | simulation connection part 5 that satisfies this assumption, if the 4th connection body 54 can be detected, it will be considered that the general connection body detectable condition is satisfy | filled. Can do it. However, depending on the environmental conditions during operation of the vehicle detector 1 and the laser light reflection characteristics of the surface of the connected body, more severe connected body detection conditions may be required, so that the fifth connected body 55 can be detected. If the connection body detectable condition is set, detection of the connection body by the vehicle detector 1 can be further ensured.

  Further, when the vehicle 2 passes through the ETC lane, if the vehicle 2 travels near the island where the vehicle detector 1 is installed, the distance from the light transmitting / receiving unit 12a of the laser scanner 12 to the pseudo-connecting unit 5 is shortened. If the vehicle travels away from the island where the detector 1 is installed, the distance from the light transmitting / receiving unit 12a of the laser scanner 12 to the pseudo-connecting unit 5 increases. Since the distance from the side surface of the automobile 2 to the pseudo connection portion 5 is constant at 865 [mm], the separation distance to the pseudo connection portion 5 can be adjusted by adjusting the distance X from the vehicle detector 1 to the side surface of the automobile 2. Can be set arbitrarily. For example, when X = about 635 [mm], the separation distance is about 1.5 [m], and when X = about 1135 [mm], the separation distance is about 2.0 [m], and X = about 1635 [m]. mm], the separation distance is about 2.5 [m], X = about 2135 [mm], the separation distance is about 3.0 [m], and X = about 2635 [mm], the separation distance is If the distance is about 3.5 [m] and X = about 3135 [mm], the separation distance is about 4.0 [m], and if X = about 3635 [mm], the separation distance is about 4.5 [m]. Become.

  FIGS. 6 to 8 are diagrams showing the results of actual measurements performed by operating the laser scanner 12 under various conditions to detect whether or not the pseudo-connection portion 5 can be detected, and the calculation results under the same conditions by simulation software. is there. In general, the actual measurement result tends to exhibit a higher connected body detection capability than the calculation result, but this is a simple calculation method that does not consider the laser beam spread angle [rad]. This is probably because the spot diameter at a long-distance point becomes larger and the detection possibility increases. In any case, the difference between the calculation result and the measurement result is generally within an error range, and a high correlation is recognized between the measurement result and the calculation result. Therefore, it is considered that the detection status of the pseudo-connecting unit 5 based on the actual measurement result is reliable in searching for the connected body detectable condition.

  In FIG. 6, the installation height of the laser scanner 12 is set to 2.5 [m], and the separation distance from the vehicle detector 1 to the pseudo-connecting portion 5 is set in seven stages (for example, about 1.5 [m], About 2.0 [m], about 2.5 [m], about 3.0 [m], about 3.5 [m], about 4.0 [m], about 4.5 [m]) These are the results of scanning at five different scan frequencies (for example, 25 [Hz], 35 [Hz], 50 [Hz], 75 [Hz], and 100 [Hz]). In the laser scanner 12 used for actual measurement, the step angle at a scan frequency of 25 [Hz] is 0.1667 [°], the step angle at a scan frequency of 35 [Hz] is 0.25 [°], and a scan frequency of 50 The step angle at [Hz] is 0.3333 [°], the step angle at scan frequency 75 [Hz] is 0.5 [°], and the step angle at scan frequency 100 [Hz] is 0.6667 [°]. It is. As described above, the laser scanner 12 has a higher angular resolution as the scanning frequency is lower, so that fine scanning is possible. The lower the scanning frequency, the larger the number of detection points obtained from the pseudo-connection unit 5.

  In the calculation result obtained by scanning the pseudo-connection portion 5 from a height of 2.5 [m], it is a limit to detect the fourth connection body 54 at a position separated by about 4 [m] at a scan frequency of 50 [Hz]. The fourth connected body 54 cannot be detected at the scan frequencies 75 [Hz] and 100 [Hz]. However, in the actual measurement result of scanning the pseudo-connection portion 5 from the height of 2.5 [m], the fourth connection body 54 at a position separated by about 3.5 [m] is detected at the scan frequency of 75 [Hz]. Yes. In any case, if the installation height of the laser scanner 12 is 2.5 [m] too high to detect the pseudo-connecting portion 5 arranged around 320 [mm] to 720 [mm] from the road surface. Conceivable.

  In FIG. 7, the installation height of the laser scanner 12 is set to 1.5 [m], and the separation distance from the vehicle detector 1 to the pseudo-connecting portion 5 is changed in seven stages, and scanning is performed at five different scan frequencies. It is a result. In the calculation result obtained by scanning the pseudo-connection portion 5 from a height of 1.5 [m], it is limited to detect the fourth connection body 54 at a position separated by about 3 [m] at a scan frequency of 75 [Hz]. . However, in the actual measurement result of scanning the pseudo-connection portion 5 from the height of 1.5 [m], the fourth connection body 54 at a position separated by about 3.5 [m] is detected at the scan frequency of 75 [Hz]. Yes. In addition, when the scan frequency is 75 [Hz], the fifth connected body 55 at a position separated by about 3.0 [m] is detected. Therefore, if the scanning frequency is 75 [Hz], it is considered that the certainty that the fourth connected body 54 at a position separated by about 3.0 [m] can be detected is higher.

  In FIG. 8, the installation height of the laser scanner 12 is set to 1.0 [m], and the separation distance from the vehicle detector 1 to the pseudo-connecting portion 5 is changed in seven steps, and scanning is performed at five different scan frequencies. It is a result. In the calculation result obtained by scanning the pseudo-connection portion 5 from a height of 1.0 [m], it is a limit to detect the fourth connection body 54 at a position separated by about 3 [m] at a scan frequency of 75 [Hz]. . However, in the actual measurement result of scanning the pseudo-connection portion 5 from a height of 1.0 [m], the fourth connection body 54 at a position separated by about 3.5 [m] is detected at a scan frequency of 75 [Hz]. Yes. In addition, when the scan frequency is 75 [Hz], the fifth connected body 55 at a position separated by about 3.0 [m] is detected. Therefore, it is considered that the certainty that the fourth connected body 54 at a position separated by about 3.0 [m] can be detected at a scanning frequency of 75 [Hz] is higher.

  From the above results, when the installation height of the laser scanner 12 is set in the range of 1.5 [m] to 1.0 [m], the scan frequency is 75 [Hz] and the distance is about 3.0 [m]. It is possible to detect the first to fifth connected bodies 51 to 55 (approximately in the range of 300 [mm] to 700 [mm] in height from the road surface) at the positions.

  FIG. 9 is a characteristic diagram showing the relationship between the vehicle speed [km / h] calculated and measured for each scan frequency of the laser scanner 12 and the vehicle traveling direction resolution accuracy [mm]. Theoretically, if the scan frequency is constant, the installation speed of the laser scanner 12 is not affected, and the vehicle speed and the vehicle traveling direction resolution accuracy are directly proportional, and the vehicle traveling direction resolution accuracy increases as the vehicle speed increases. It becomes rough (detectable interval becomes long). The actual measurement results shown in FIG. 9 are measured only at a vehicle speed of 5 [km / h], 10 [km / h], 20 [km / h], 30 [km / h], and 40 [km / h]. Since the proportional straight line obtained at the vehicle speed of 0 to 40 [km / h] is extended to the vehicle speed of 100 [km / h], the error in the range of the vehicle speed of 0 to 40 [km / h] is emphasized. It is considered that the variation in the vehicle traveling direction resolution accuracy at [km / h] has become significant. Therefore, in the following, consideration will be given based on the characteristic line of the calculation result.

  When the automobile 2 passes through the ETC lane, the approach speed is regulated to 20 [km / h] or less, so the laser scanner 12 operated at a scan frequency of 25 [Hz] (vehicle traveling direction resolution accuracy is 230 [mm]. However, there is no particular problem in detecting the pseudo-connecting portion 5 having a length of 660 [mm]. However, since the automobile 2 may enter the ETC lane at 40 to 50 [km / h] without adhering to the regulated speed, scanning is considered when the vehicle speed is about 40 to 50 [km / h]. Since the vehicle traveling direction resolution accuracy when the laser scanner 12 is operated at a frequency of 25 [Hz] is about 440 to 560 [mm], there is a high possibility that the pseudo-connection portion 5 can barely be detected at one point or more.

  On the other hand, when the automobile 2 passes through the gantry without reducing the vehicle speed as in free flow ETC, the speed is 80 to 100 [km / h], so the scan frequencies of 25 [Hz] and 35 [Hz] The detection of the pseudo-connecting portion 5 is uncertain with respect to the vehicle traveling direction resolution accuracy. However, since the resolution in the vehicle traveling direction when the laser scanner 12 is operated at a scan frequency of 50 [Hz] is about 450 to 550 [mm], the pseudo-connecting portion 5 can be barely detected. Furthermore, since the vehicle traveling direction resolution accuracy at a scan frequency of 75 [Hz] is about 300 to 370 [mm], the pseudo-connecting portion 5 can be detected more reliably. In addition, since the vehicle traveling direction resolution accuracy at a scan frequency of 100 [Hz] is increased to about 220 to 270 [mm], the pseudo connection portion 5 may be detected at 2 to 3 points, but the scan frequency of 100 When the laser scanner 12 is operated at [Hz], the step angle increases to near 0.7 [°], so that sufficient detection resolution cannot be obtained.

  From the above results, if the laser scanner 12 is operated at a scan frequency of 75 [Hz], even if the installation height of the laser scanner 12 is arbitrarily set in the range of 1000 [mm] to 2500 [mm], the speed is 100 Scans 1 to 2 first to fifth connected bodies 51 to 55 (approximately 300 mm to 700 mm in height from the road surface) attached to the automobile 2 traveling at [km / h]. It becomes possible.

  In order to set a connected body detectable condition for detecting a connected body that connects the automobile 2 and the towed object using the laser scanner 12 having the above-described performance, when the automobile 2 enters the ETC lane, Even if the passage position of the laser beam changes, it is necessary to set in advance a range in which the coupling body is highly likely to pass within the scan plane of the laser scanner 12. That is, if the connected body detection area δ is appropriately set as a region through which the connected body that connects the automobile 2 and the towed object is likely to pass, the connected body is set in the entire range of the connected body detection area δ. This is because the conditions for enabling detection can be narrowed down. A setting example of the connected body detection area δ will be described with reference to FIG.

  In the ETC lane, which is a toll collection facility, the building limit γ of the toll gate is defined as shown in FIG. 10, and various facilities are provided so as not to enter the building limit γ. For example, the straight line distance from the reference island 31a, which is the vehicle detection reference when the vehicle detector 1 is installed, to the adjacent island 31b adjacent in the scanning direction (right side in FIG. 10) by the vehicle detector 1 is about 3.0. [M] is the vehicle passage area. The islands 31a and 31b can be installed at a height of 250 [mm] from the road surface, and are included in the construction limit γ from the side edge facing the lane of each island 31a and 31b to 250 [mm]. Therefore, the vehicle detector 1 is provided at a position separated by 250 [mm] from the outer edge facing the lane of the island 31a.

  According to the vehicle detector 1 installed at the position, most of the area within the building limit γ on the scanable detection surface is included in the scan range, and the automobile 2 passing through the ETC lane can be reliably detected. However, since the scan elevation angle of the laser scanner 12 is about 73 °, an undetectable region is formed immediately above the vehicle detector 1. The range of 17 ° where the laser beam LB is not irradiated is about 810 [mm] on the upper limit horizontal plane of the building limit γ, and if a load at a high position of a large truck is in this undetectable region, the load of this portion, etc. Cannot be detected. However, it is rare that a large truck or the like carrying a long load such as dredged material at a high position of 3 to 4 [m] passes, and a part of the load was in an undetectable region. However, it is considered that there is no special trouble in the entry detection and the passage detection of the automobile 2 in the ETC lane.

  Since the lane width formed between the reference island 31a and the adjacent island 31b is about 3000 [mm] due to the binding of the building limit γ described above, the pseudo-connecting portion 5 attached to the automobile 2 passing through the substantially horizontal lane. Generally exists in the range of about 315 [mm] to 740 [mm] in the vertical direction from the road surface. Accordingly, if the longitudinal range of the connected body detection area δ is set to about 300 [mm] to 800 [mm] from the road surface, the lower end to the upper end of the pseudo-connecting portion 5 (the first to fifth connected bodies 51 to 55). All) can be included in the detectable range.

  In the ETC lane, the automobile 2 does not necessarily pass through the center of the lane, and may be close to the reference island 31a side or close to the adjacent island 31b side. Therefore, a connected body detection including a pseudo-connecting portion 5 'of the automobile 2' traveling extremely close to the reference island 31a and a pseudo-connecting portion 5 "of the automobile 2" traveling extremely close to the adjacent island 31b. The horizontal range of the area δ ranges from about 1100 [mm] to 2400 [mm] in the horizontal direction from the vehicle detector 1 (from about 850 [mm] to 2150 [mm] in the horizontal direction from the outer edge of the reference island 31a. (Range) is sufficient.

  That is, a range of height 500 [mm] × width 1300 [mm] in contact with a vertical line about 1100 [mm] away from the vehicle detector 1 and a horizontal line about 300 [mm] away from the road surface is connected. If the body detection area δ is set, the pseudo-connection portion 5 is always included in the connection body detection area δ no matter where the vehicle 2 is traveling in the lane. 10 is set as a range in which all of the first to fourth connected bodies 51 to 55 can be detected within the lane range in which the automobile 2 can travel. However, in an actual ETC lane, the possibility that the car 2 will travel extremely close to the reference island 31a and the adjacent island 31b is extremely low, and the installation height of the standard connecting body can be further narrowed down. Is set to the connected body detection area δ, there is no practical problem.

  Next, a scan condition that can detect a connected body (for example, the smallest fifth connected body 55) within the entire range of the connected body detection area δ set as described above is set.

  As shown in FIG. 10, the vehicle detector 1 installed on the island 31 a is configured by arranging the light transmitting / receiving unit 12 a of the laser scanner 12 at a height of 1250 [mm] from the road surface (hereinafter simply referred to as installation height). However, the detection performance when the installation height of the laser scanner 12 is 1250 [mm] is not actually measured. However, the detection performance when the installation height of the laser scanner 12 is 1250 [mm] includes the characteristics (see FIG. 7) that the installation height of the laser scanner 12 is 1500 [mm], and the installation of the laser scanner 12. It can be estimated that the height is intermediate between the characteristic of 1000 [mm] (see FIG. 8). Therefore, in the following description, the actual measurement results (characteristics in which the installation height of the laser scanner 12 is set to 1500 [mm]) in which the detection performance is inferior due to the long separation distance to the connected body detection area δ are shown in FIG. Assuming the detection performance when the installation height of 12 is 1250 [mm], the scanning conditions are examined.

  For example, from the detection characteristics of the laser scanner 12 with a scan frequency of 100 [Hz], when the installation height of the laser scanner 12 is 1.5 [m], the fifth connected body that is the smallest among the pseudo-connecting portions 5. 55 can be detected stably up to the position where the distance in the horizontal direction is about 2.5 [m], and the detection performance that can cover about 3.5 [m] to the adjacent island 31b cannot be expected. However, the farthest part of the connected body detection area δ has a horizontal distance of about 2.4 [m] from the vehicle detector 1 and an installation height of 1.5 [m] with a scan frequency of 100 [Hz]. Since the laser scanner 12 can detect the fifth connecting body 55 separated by about 2500 [mm] in the horizontal direction, it can barely be determined that the connecting body can be detected in the entire range of the connecting body detection area δ.

  Further, when the scan frequency is lowered below 100 [Hz], the step angle for irradiating the laser beam becomes fine, so that the scan frequency is set to 75 [Hz], 50 [Hz], 35 [Hz], or 25 [Hz]. Also in the set laser scanner 12, it is possible to almost certainly detect the fifth coupling body 55 separated by about 2500 [mm] in the horizontal direction. That is, if the laser scanner 12 having an installation height of 1.5 [m] is operated at a scan frequency of 100 [Hz] or less (step angle is 0.6667 [°] or less), the connected body detection area δ Stable connection can be detected in the entire range.

  Therefore, in the laser scanner 12 having an installation height of 1.25 [m], the connected body detection area δ can be detected if the step angle is set to 0.6667 [°] or less with respect to the connected body detection area δ. Some of the conditions can be met.

  On the other hand, since the automobile 2 entering the ETC lane travels on the lane toward the gate, the connecting body that connects the automobile 2 and the to-be-towed object is the scan plane of the laser scanner 12 (the automobile 2 is perpendicular to the road surface). It is also necessary to consider the conditions that are detected at one or more locations while passing through a plane that intersects the passing direction. When the automobile 2 passes through the ETC lane, although there is a speed limit of 20 [km / h], there are actually vehicles that enter the ETC lane at 30 to 40 [km / h]. h]] (see FIG. 9), the lowest scanning frequency of the laser scanner 12 with an installation height of 1.5 [m] is about 380 [mm]. The vehicle traveling direction resolution is accurate. That is, when the laser scanner 12 having an installation height of 1.5 [m] is operated at a scan frequency of 25 [Hz] or higher, a connected body having a length of about 500 to 600 [mm] is 40 [km / h]. In the following, when passing through the connected body detection area δ, this can be detected at one or two places.

  Accordingly, in the laser scanner 12 having an installation height of 1.25 [m], if the scan frequency is set to 25 [Hz] or more with respect to the traveling speed of 40 [km / h] or less of the automobile 2, It is possible to satisfy a part of the connected body detectable condition.

  From the above considerations, it is assumed that the laser scanner 12 having the characteristics shown in FIGS. 6 to 9 is installed at a height of 1.25 [m], and the allowable upper limit speed of the automobile 2 is 40 [km / h] or less. When the fifth connected body 55 (length 10 [mm] × width 50 [mm] × length 660 [mm]) is set to the smallest and difficult to detect shape, the connected body is one or more in the connected body detection area δ. As for the condition for detecting the connected body for detection, the scan frequency is 25 [Hz] or more and the angular resolution is a step angle of 0.6667 [°] (in the laser scanner 12 used for actual measurement, the scan frequency is equivalent to 100 [Hz]. )

  That is, as shown in FIG. 10, for the vehicle detector 1 installed on the reference island 31a in the ETC lane and the connected body detection area δ set in advance within the scan range, the laser scanner 12 is 25 [ Operating at a scan frequency of Hz] to 100 [Hz] is a condition for detecting a connected body. Also, considering the balance between the scan frequency (scan interval in the vehicle traveling direction) and the angular resolution among the connected body detectable conditions, the scan frequency of the laser scanner 12 may be set to 70 [Hz] or 50 [Hz]. desirable. Of course, if a higher-performance laser scanner than the laser scanner 12 having the characteristics shown in FIGS. 6 to 9 can be used, a higher angular resolution can be obtained at a higher frequency. The frequency can be set with a short period of 150 [Hz] to 200 [Hz]. On the other hand, when a laser scanner having a lower performance than the laser scanner 12 having the characteristics shown in FIGS. 6 to 9 must be used, the laser scanner is operated at a low frequency at which necessary and sufficient angular resolution can be obtained, It may be adjusted so as to satisfy the connected body detectable condition by setting the permissible upper limit speed to a low value.

  The vehicle detector 1 configured as described above is provided on the island 31 of the ETC lane according to the detection purpose. Specifically, as shown in FIG. 11, the vehicle detector 1-1a for detecting the first vehicle entry is located closest to the entry direction of the automobile 2 (upstream side), and the second vehicle is located downstream of the vehicle detector 1-1a. A vehicle detector 1-1b for detecting entry, a vehicle detector 1-2 for detecting communication completion timing on the downstream side, and a vehicle detector for detecting first vehicle exit on the further downstream side of the receiving booth 32. 1-4a is provided with a vehicle detector 1-4b for detecting a second vehicle exit on the further downstream side with the start control rod 33 interposed therebetween. The vehicle approach detection signal and the vehicle passage detection signal output from each of the vehicle detectors 1-1a, 1-1b, 1-2, 1-4a, 1-4b are transmitted to the lane control device that controls the lane. Sent.

  When the automobile 2 enters from the normal approach direction, it passes through the detection area DA1a by the laser scanner 12 of the vehicle detector 1-1a for detecting the first vehicle entry first, and then detects the vehicle for detecting the second vehicle entry. It passes through the detection area DA1b by the laser scanner 12 of the device 1-1b. Therefore, after the vehicle entry detection signal is output from the vehicle detector 1-1a for detecting the first vehicle entry, the vehicle entry detection signal is output from the vehicle detector 1-1b for detecting the second vehicle entry. In the lane control device, it can be determined that the automobile 2 has entered from the normal approach direction. And the instruction | indication for starting radio | wireless communication with the ETC apparatus mounted in the approaching vehicle is performed. When the vehicle 2 runs backward or reverses the lane in the ETC lane, the first vehicle entry detection signal is output after the vehicle entry detection signal is output from the second vehicle entry detection vehicle detector 1-1b. Since the vehicle approach detection signal is output from the vehicle detector 1-1a, the lane control device can know the inappropriate traveling state.

  The laser scanner 12 of the vehicle detector 1-1a for detecting the first vehicle entry located on the most upstream side transmits point cloud data obtained every scan cycle to a processing device (detailed later). Then, processing such as detection of a connected body is performed by appropriately processing with a processing device. Note that the point cloud data obtained from the laser scanner 12 for each scan cycle is not limited to the data transmitted from the vehicle detector 1-1a for detecting the first vehicle entry, and other vehicle detectors 1-1b, 1- 2, 1-4a, 1-4b may be transmitted to the processing device.

  As described above, after the automobile 2 enters the ETC lane from the normal approach direction, after the wireless communication with the in-vehicle ETC device is started, the automobile 2 detects the vehicle detector 1 for detecting the communication completion timing. When passing the detection area DA2 by the second laser scanner 12, a vehicle approach detection signal is transmitted to the lane control device, thereby giving an instruction to end wireless communication with the in-vehicle ETC device. If the communication result with the ETC in-vehicle device is normal, the lane control device instructs the host device via the communication network, such as a charge reduction, and outputs an open signal to the start control rod 33 to start control. Open the rod 33. If the communication result with the ETC in-vehicle device is abnormal, the processing device keeps the start control rod 33 closed, and an attendant will respond at the collection booth 32.

  When the start control rod 33 is opened by a command from the lane control device and the automobile 2 leaves the toll gate, the automobile 2 first passes the detection area DA4a by the laser scanner 12 of the vehicle detector 1-4a for detecting the first vehicle exit. After that, the automobile 2 passes through the detection area DA4b by the laser scanner 12 of the vehicle detector 1-4b for detecting the second vehicle exit. Accordingly, after the vehicle entry detection signal is output from the vehicle detector 1-4a for detecting the first vehicle exit, the vehicle entry detection signal is output from the vehicle detector 1-4b for detecting the second vehicle exit. In the lane control device, it can be determined that the automobile 2 has left in the normal exit direction. When the vehicle 2 completely passes through the gate and a vehicle passage detection signal is output from the vehicle detector 1-4b for detecting the second vehicle exit, the lane control device outputs a closing signal to the start control rod 33. Then, the start control rod 33 is closed.

  It should be noted that when passing through the detection area DA4b by the laser scanner 12 of the vehicle detector 1-4b for detecting the second vehicle leaving, even if the automobile 2 is connected to the towed object, a scan that satisfies the connected body detection condition is satisfied. If the vehicle is operating at a frequency, the vehicle detector 1-4b does not output a vehicle passage detection signal until the coupled body and the towed object have completely passed. Thus, it is possible to prevent a problem that the start control rod 33 is closed. In addition, even when the automobile 2 such as a truck is loaded with a long load, if the vehicle detector 1-4b detects a load protruding rearward from the rear part of the vehicle body, a vehicle passage detection signal is generated. Since it is not output, it is possible to prevent a problem that the start control rod 33 is closed while a long load projecting from the rear part of the vehicle body is passing.

  However, since the vehicle detector 1 is installed on the reference island 31a along the side boundary edge of the building limit γ, as described above, an undetectable region outside the irradiation range of the laser beam LB of the laser scanner 12 occurs. End up. When a long load passes through this undetectable area, the load cannot be detected by the vehicle detector 1, so that the long load protruding from the rear of the vehicle body is passing through the gate. There is a risk that a vehicle passage detection signal is output from the vehicle detector 1-4b and the start control rod 33 is closed. When such a situation occurs, there is a possibility that the load of the passing vehicle may be damaged or the start control rod 33 itself may be damaged, which is a serious problem.

  As a solution not to cause an undetectable area within the building limit γ, the vehicle detector 1 is installed at a position further separated by about 810 [mm] from the boundary edge of the building limit γ, and the undetectable area is set to the building limit γ. It is conceivable to shift outward. However, when the vehicle detector 1 is moved away from the outer edge of the island 31, the connected body detection performance in the connected body detection area δ is lowered, and the setting of the connected body detection possible condition is affected. Thus, such a solution is not practical.

  Therefore, as a more realistic solution, the vehicle detector 1-4b for detecting the second vehicle exit is not the vehicle detector 1 with an overall height of 1500 [mm] but an overall height of 1750 [mm] shown in FIG. Using the vehicle detector 1 ', the non-detectable region generated within the building limit γ is narrowed to a practically negligible level. That is, the vehicle detector 1 ′ extends the distance from the center of the light transmitting / receiving unit 12a of the laser scanner 12 to the upper wall portion 14c of the optical path protecting unit 14 to 603 [mm], and the elevation angle of the scanning range α is about 80 °. The undetectable area has been reduced. As a result, the range of about 10 ° where the laser beam LB is not irradiated is suppressed to about 423 [mm] on the upper horizontal plane of the building limit γ, and the automobile 2 such as a large truck approaches the reference island 31a side extremely. Even if it has been done, the possibility that a load at a high position of a large truck enters this undetectable region can be substantially eliminated.

  Therefore, if the vehicle detector 1 ′ is used as the vehicle detector 1-4 b for detecting the second vehicle exit, the vehicle detector is in the middle of the long load at the high position of the automobile 2 passing through the gate. The risk that the vehicle passage detection signal is output from 1-4b and the start control rod 33 is closed can be effectively avoided.

  The toll type vehicle detector 1 ′ that can narrow the undetectable area is not only the vehicle detector 1-4b for detecting the second vehicle exit, but also the vehicle detector 1-1a for detecting the first vehicle entry, Although it may be used for the vehicle detector 1-1b for detecting the second vehicle entry, the vehicle detector 1-2 for detecting the communication completion timing, and the vehicle detector 1-4a for detecting the first vehicle exit, The vehicle detector 1 'is more expensive than the normal type vehicle detector 1 and has a total length of 1750 [mm], which may impair visibility in the ETC lane. Therefore, it is practical to use the toll type vehicle detector 1 ′ only for the vehicle detector 1-4b for detecting the second vehicle exit that needs to narrow the undetectable region.

  If the above-described vehicle detector 1 ′ is further modified so that the distance from the center of the light transmitting / receiving unit 12a of the laser scanner 12 to the upper wall portion 14c of the optical path protecting unit 14 is further extended from 603 [mm], scanning is performed. It is possible to further reduce the non-detectable region in which the elevation angle of the range α can be made closer to 90 °. However, if such a structure is used, the problem of increased cost and reduced visibility due to the lengthening of the housing 11 arises. Therefore, the vehicle detector 1 'having an elevation angle of the scan range α of 80 ° has a practically excellent structure. I can say that.

  If the optical path protection unit 14 in the vehicle detector 1 reaches the hemispherical apex 11b, the elevation angle of the scan range α can be increased to more than 90 °, and the undetectable area can be reduced without increasing the length of the housing 11. it can. However, with such a structure, the upper side of the light transmitting / receiving part 12a of the laser scanner 12 cannot be protected by the upper wall part 14c, so that the light transmitting / receiving part 12a of the laser scanner 12 is directly exposed to rain or snow. Measures for aqueous humor are necessary to prevent snow from entering the equipment. In addition, since snow, fallen leaves, and the like enter the optical path protection unit 14 that is no longer protected by the hemisphere top 11b, snow, fallen leaves, etc. accumulate on the upper surface side of the light transmission / reception unit 21a of the laser scanner 12 to transmit / receive the laser beam LB. There is also a risk of being disturbed. Therefore, the vehicle detectors 1 and 1 'having the upper wall portion 14c in the optical path protection unit 14 that protects the optical path of the transmitted light irradiated from the laser scanner 12 and the reflected light that returns to the detection target are practically excellent structures. It can be said.

  Next, an outline of the vehicle detection system 100 constructed using the vehicle detector 1 will be described with reference to FIG. The vehicle detection system 100 according to the present embodiment includes the vehicle detector 1 that can send the point cloud data acquired by the laser scanner 12 and the processing device 110 that processes the point cloud data.

  In addition, although the processing apparatus 110 in this embodiment processes the detection information (vehicle detection signal S1a and point cloud data) from the vehicle detector 1-1a for 1st vehicle approach detection, it does not restrict to this. The vehicle detector 1-1b for detecting the second vehicle entry, the vehicle detector 1-2 for detecting the communication completion timing, the vehicle detector 1-4a for detecting the first vehicle exit, and for detecting the second vehicle exit. You may make it provide the processing apparatus 110 corresponding to the vehicle detector 1-4b. Alternatively, the detection information output from each of the plurality of vehicle detectors 1 may be processed in parallel by one processing device 110. Further, the processing device 110 may be provided in the toll booth 32 or may be provided at an appropriate place on the island 31 like the lane control device 200. Alternatively, the processing device 110 may be housed in the housing 11 of the vehicle detector 1 so that the vehicle detection system 100 has an integrated structure.

  The point cloud data output from the vehicle detector 1-1a is input to the filter unit 111 of the processing device 110, and after noise is removed, the point cloud data is supplied to the 3D image generation unit 112. When the point cloud data input for each scan cycle from the laser scanner 12 of the vehicle detector 1-1a is arranged in time series, the three-dimensional shape of the irradiation surface of the laser beam LB is obtained (for example, FIG. 14 (a)). See).

  Further, the speed signal Sv of the automobile 2 is input to the 3D image generation unit 112 from the speed detector 120 provided at an appropriate position on the island 31. From the scan cycle of the laser scanner 12 and the speed of the automobile 2, the 3D image generation unit 112 Since the vehicle movement distance can be obtained, the 3D image generation unit 112 can generate a 3D image with less distortion. The speed signal Sv ′ (shown by a broken line in FIG. 13) of the automobile 2 detected by the auxiliary laser scanner 13 provided in the vehicle detector 1 is supplied to the 3D image generating means 12 and used for generating a 3D image. Anyway. Alternatively, the vehicle detection signal S1b from the vehicle detector 1-1b for detecting the second vehicle entry is supplied to the 3D image generating means 112 (indicated by a broken line in FIG. 13), and the vehicle detection for detecting the first vehicle entry is performed. Based on the detection time difference between the vehicle detection signal S1a from the detector 1-1a and the vehicle detector 1-1b for detecting the second vehicle entry, and the separation distance between the vehicle detector 1-1a and the vehicle detector 1-1b. The 3D image generation means 112 may obtain the speed of the automobile 2 and generate a 3D image using this simple vehicle speed.

  The 3D image of the automobile 2 obtained by the 3D image generation means 112 is supplied to the vehicle detection means 113 and the connection body detection means 114, and for example, the body of the automobile 2 and the connection body are detected by image recognition technology.

  The vehicle detection unit 113 efficiently detects the vehicle 2 from the 3D image supplied from the 3D image generation unit 112, for example, by setting the side surface of the vehicle 2 as shown in FIG. Can be done. In the vehicle detection means 113, when a separation space (non-detection area) of about 50 [cm] or more exists before and after the lump with continuous detection surfaces, the lump with continuous detection surfaces is detected as one automobile 2. it can. Of course, even when a connected body is obtained as point cloud data by the vehicle detector 1-1a, even when a long load loaded on the automobile 2 and protruding rearward or forward is obtained as point cloud data. A lump with continuous detection surfaces can be detected as a single vehicle.

  In FIG. 14B, the to-be-to-be-towed object 6 passes from the detection front end P1 that detects the automobile 2 after the non-detection state of 50 [cm] or more continues, through the automobile 2 body, the vehicle body fixture 4 and the pseudo-connecting portion 5. Up to the detection rear end P2, which is the last edge of the vehicle, is detected as one vehicle. In addition, since the non-detection state of 50 [cm] or more continues behind the detection rear end P2, it can be clearly distinguished from the automobile 2 continuing from the rear. Further, the vehicle detection unit 113 outputs a vehicle detection signal to the passing vehicle specifying unit 115 every time one vehicle 2 is detected. At this time, the length information of the detected vehicle may be included as the vehicle detection signal.

  On the other hand, the connected body detection means 114 detects the connected body in the connected body detection area δ of the 3D image supplied from the 3D image generation means 112. The connected body detection area δ is information set in advance in the connected body detection unit 114, and the maximum size to the minimum size of the connected body to be detected are also set in the connected body detection unit 114 in advance. Therefore, the connected body detection means 114 can detect the connected body by determining whether or not there is a detected object of a size considered to be a connected body in the connected body detection area δ. The connected body detection means 114 outputs a connected body detection signal to the passing vehicle specifying means 115 when detecting the connected body. At this time, the connection body detection position information (for example, the length from the detection tip P1 to the connection body detection position) may be included as the connection body detection signal.

  Note that if a long load such as a saddle material happens to be in the connected body detection area δ, the connected body detecting means 114 may erroneously detect this as a connected body. However, in the passing vehicle specifying means 115, the length of the detected vehicle included in the vehicle detection signal and the connection body detection position information included in the connection body detection signal have a size that is considered to be a towed object behind the connection body. If there is a non-detected object or no such non-detected object, it can be determined whether the vehicle consists of a tow vehicle and a towed object, or a single vehicle with a long load. Appropriate passing vehicles can be identified.

  Alternatively, the connected body detection means 114 determines whether there is a large detected object (towed object) exceeding the connected body detection area δ behind the detected object of a size considered to be a connected body, and considers it as a connected body. Only when a large detected object is present behind the detected object, it may be determined that a connected body is detected. In this way, since there is no towed object behind the load that extends rearward like the dredged material, the connected body detection means 114 erroneously detects a long load extending rearward as a connected body. Can be reduced, and the reliability of the detection function of the connected body detection means 114 can be improved.

  As described above, the passing vehicle specifying means 115 that receives the vehicle detection signal output from the vehicle detection means 113 and the connection body detection signal output from the connection body detection means 114 is for the automobile 2 that passes through the ETC lane. Then, it is specified whether the vehicle is a single vehicle or a vehicle composed of a tow vehicle and a towed object, and the passing vehicle information is transmitted to the lane control device 200.

  Since the lane control device 200 is a device that performs communication control with the ETC device mounted on the automobile 2 that passes through the ETC lane, in order to know the entry timing and the passage timing of the automobile 2 at key points, the first vehicle entry detection is performed. From the detection signal S1a output from the vehicle detector 1-1a for detection, the detection signal S1b output from the vehicle detector 1-1b for detection of the second vehicle entry, and from the vehicle detector 1-2 for detection of communication completion timing The detection signal S2 output, the detection signal S4a output from the vehicle detector 1-4a for detecting the first vehicle exit, and the detection signal S4b output from the vehicle detector 1-4b for the second vehicle exit detection are received. .

  In the vehicle detection system 100 of the present embodiment, the detection signal S1a from the vehicle detector 1-1a for detecting the first vehicle entry is not directly input to the vehicle control device 200 but supplied via the processing device 110. It was supposed to be. That is, by providing the detection output switching means 116 in the processing device 110, the raw detection signal S1a, the highly reliable detection signal from which noise is removed by the filter means 111, and the vehicle detection signal output from the vehicle detection means 113 are provided. Any of these can be switched arbitrarily and supplied to the vehicle control device 200. In this way, by setting in advance the detection output switching means 116 which detection signal is supplied to the lane control device 200, a detection signal according to the purpose can be output from the processing device 110 to the lane control device 200. , It will be highly flexible.

  In the passing vehicle specifying means 115 that has received the vehicle detection signal from the vehicle detection means 113 and the connection body detection signal from the connection body detection means 114, the passing vehicle is a single vehicle or a vehicle composed of a tow vehicle and a connected object. However, detailed information such as the vehicle type classification of the passing vehicle (light cars, ordinary cars, medium-sized cars, large-sized cars, extra-large-sized cars) and the number of axles cannot be specified. In order to obtain more detailed information on the passing vehicle in the processing device 110, the processing device 110 may be provided with a feature point extraction means 117, a vehicle type identification means 118, and a vehicle type discrimination information storage means 119. Good (indicated by a broken line in FIG. 13).

  For example, a 3D image of the vehicle generated by the 3D image generation unit 112 is transmitted to the feature point extraction unit 117, and the feature point extraction unit 117 extracts a feature point from a place considered to be important for specifying the vehicle type. Extracted and transmitted to the vehicle type specifying means 118. If the feature point extracting means 117 extracts the feature point of the rod-like body extending backward from the rear part of the vehicle body in the connected body detection area δ, the vehicle type specifying means 118 determines whether the connected body exists from the feature point. I can judge.

  Based on the feature points extracted from the feature point extraction unit 117, the vehicle type identification unit 118 determines the presence or absence of the towed object from the presence or absence of the connected body. From the similarity with the feature point group stored as the vehicle type discrimination information read from the discrimination information storage unit 119, the vehicle type of the vehicle is specified. Further, when it is determined that the connected body exists, the vehicle type specifying unit 118 stores the feature points of the towing vehicle on the front side of the connected body and the feature points stored as the vehicle type determination information read from the vehicle type determination information storage unit 119. The model of the tow vehicle can be identified from the similarity with the group. When specifying the vehicle type, the number of axles of the vehicle can also be specified by the number of tires that appear round in the lower part of the vehicle body. Further, if there is a load that extends rearward or forward from the vehicle body of the specified vehicle type, if these are extracted as feature points, it can be specified as a vehicle having a long load.

  The detailed information of the passing vehicle specified by the vehicle type specifying unit 118 as described above is transmitted to the lane control device 200 via the passing vehicle specifying unit 115. For example, when the lane control device 200 compares the information acquired from the ETC terminal device mounted on the passing vehicle with the detailed information of the passing vehicle specified by the vehicle type specifying means 118 of the processing device 110, and there is a mismatch. Since there is a possibility that the vehicle information set in the ETC terminal device is incorrect, the ETC system does not automatically collect tolls and stops the vehicle 2 without opening the start control rod 33. It is possible to switch to a response by a staff member at the collection booth 32. In other words, if the processing device 110 can specify the detailed information of the passing vehicle, it is possible to reduce the trouble that the ETC system automatically collects a charge different from the original charge imposed on the passing car 2 and the reliability as a system. Can increase the sex.

  As mentioned above, although the embodiment of the vehicle detector and the vehicle detection system according to the present invention has been described based on the accompanying drawings, the present invention is not limited to these embodiments, and the configuration described in the claims As long as the above is not changed, it may be carried out by diverting known equivalent technical means.

DESCRIPTION OF SYMBOLS 1 Vehicle detector 11 Housing 12 Laser scanner 12a Transmission / reception part 14 Scan guide recessed part 2 Automobile 100 Vehicle detection system 110 Processing apparatus

Claims (6)

A housing installed on one side of a vehicle passage area through which the vehicle can pass;
A laser beam housed in the housing and capable of scanning / detecting a two-dimensional surface with a laser beam emitted from a light transmitting / receiving unit is set in a plane intersecting the traveling direction of the vehicle, and the laser beam is within the scan range. A laser scanner for acquiring point cloud data consisting of detection points detected by the light transmitting / receiving unit at a scanning period, and reflected light from a reflecting object;
An optical path protection unit that is formed in the housing and does not obstruct an optical path of irradiation light and reflected light in a scanning range of the laser scanner;
With
Within the scan range of the laser scanner, a connected body detection area is set in advance as an area where a connected body that connects a to-be-drawn object to the vehicle is likely to pass through,
When a connecting body is provided in the vehicle passing through the vehicle passage region, the allowable upper limit speed of the vehicle and the assumed shape of the connecting body are set so that the connecting body can be detected at one or more places in the connecting body detection area. A vehicle detector characterized in that the laser scanner is operated under conditions that allow detection of a connected body including a scan frequency and an angular resolution determined accordingly.   At a timing when the obstacle detection state in which no obstacle is detected in the detection space in which the obstacle is not normally detected within the scanning range of the laser scanner changes to the obstacle detection state in which the obstacle is detected in the detection space. 2. The vehicle detector according to claim 1, wherein a vehicle approach detection signal is output.   The obstacle detection state in which the obstacle is detected in the detection space where the obstacle cannot be detected at all times within the scanning range of the laser scanner has changed to the obstacle non-detection state in which the obstacle is no longer detected in the detection space. The vehicle detector according to claim 1 or 2, wherein a vehicle passage detection signal is output at a timing.   The housing includes a cylindrical portion extending in a direction perpendicular to the installation surface and a hemispherical top portion connected to a circular upper edge of the cylindrical portion, and a laser scanner having a concave chamber structure that is recessed from an appropriate place on the circumferential surface of the cylindrical portion. The vehicle detector according to any one of claims 1 to 3, further comprising a scan guide concave portion facing the light transmitting / receiving portion.   The transmitter / receiver of the laser scanner is provided at a position higher than a predetermined contamination warning range as a range in which mud splashes from the vicinity of the vehicle passage region are likely to be adhered and contaminated. The vehicle detector according to any one of claims 1 to 4, characterized in that: A vehicle detection system comprising the vehicle detector according to any one of claims 1 to 5 and a processing device that receives and processes point cloud data from the vehicle detector,
The processing device generates a 3D image by arranging the point cloud data in time series, specifies a passing vehicle type, and when detecting a connected body in the 3D image, includes the front and back of the connected body. A vehicle detection system characterized in that it is determined that one vehicle has passed.

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