HK1168459A

HK1168459A - Mobile monitoring devices and methods for vehicles

Info

Publication number: HK1168459A
Application number: HK12109105.9A
Authority: HK
Inventors: H．哈尼施; M．拉茨
Original assignee: 卡波施交通公司
Priority date: 2010-11-04
Filing date: 2012-09-17
Publication date: 2012-12-28

Description

Mobile monitoring device and method for vehicle

Technical Field

The present invention relates to a mobile monitoring device for monitoring a vehicle. The invention also relates to a method of said monitoring.

Background

In the case of vehicle monitoring, the tachometer value is often combined with the recorded image of the vehicle so that the vehicle surveillance can be clearly identified in order to perform the penalty of traffic violations. If such monitoring operations are performed from a moving motion monitoring platform, this currently requires a complex manual matching of the tachometer value to the recorded image, and the recorded image to the tachometer value, since the detection ranges of a typical tachometer sensor and image recording camera never exactly overlap. Thereby and taking into account the constantly changing relative speed in the traffic flow, ambiguities may arise between the different recorded images and the tachometer values, which makes an absolute match impossible.

Disclosure of Invention

It is an object of the present invention to provide a mobile monitoring device and method that substantially enables automatic monitoring of vehicles in a traffic stream even with both a motion monitoring platform and a moving vehicle to be monitored.

In a first aspect of the invention, this object is achieved with a mobile monitoring device having:

a sensor that measures a speed of the vehicle passing through the first detection range, the sensor providing a time stamp to a speed measurement value of the vehicle passing;

a sensor for at least indirectly measuring the geometry, preferably the length, of a vehicle passing through the second detection range, said sensor providing a time stamp to the geometry measurement of the vehicle passing;

a camera that records images of vehicles passing through the third detection range, the camera providing a time stamp to each image that the vehicle passes through; and

an evaluation device connected to the camera and the sensor, the evaluation device configured to:

from the speed measurement value, its time stamp and the first detection range, and also from the geometry measurement value, its time stamp and the second detection range, the location and time of the expected vehicle passage in the third detection range are calculated, so that from this the matching image is determined from the time stamp of the image and the third detection range.

In a second aspect of the invention, the object is achieved with a method of monitoring a vehicle, the method comprising the following steps in any desired sequence:

measuring the speed of the vehicle passing through the first detection range and providing a timestamp to the speed measurement value;

at least indirectly measuring the geometry, preferably the length, of the vehicle passing through the second detection range and providing a time stamp to said geometry measurement;

recording images of the vehicle passing through the third detection range and providing a time stamp to each image;

in addition, the method also comprises the following steps:

calculating a location and time of expected vehicle passage in the third detection range from the speed measurement value, its time stamp and the first detection range, and also from the geometry measurement value, its time stamp and the second detection range, and

whereby a matching image is determined based on the time stamp of the image and the third detection range.

The present invention takes into account different detection ranges that the respective sensors and cameras of the mobile monitoring device have, and calculates an expected value of the motion of the monitored vehicle within the detection ranges, so that it is possible to automatically associate a vehicle image recorded in one detection range with a speed measurement value originating from a detection range different from the one detection range.

The term "detection range" as used herein covers the area around each segment that can be covered by means of a sensor or camera from the current position of the mobile monitoring device, whether it is a conical section, a pyramidal section, a cylindrical section, a linear section, a planar section, etc. of an area, etc.

The calculation can also be done in the form of post-processing, i.e. the detection range or time stamp can also be assigned after all individual measurements have been made and saved.

In principle, the use of other sensors whose sensor data are adapted to the respective passing vehicle by means of the method described is also conceivable: exhaust gas sensors, sound volume sensors, temperature sensors for tire or brake inspection, video sensors for tire inspection, hazardous cargo transportation load tags, badges, stickers, and the like.

All images mentioned here can also be part of a video sequence.

A particularly preferred embodiment of the invention for monitoring vehicles equipped with DSRC OBUs (dedicated short range communication on-board units), such as those used as part of a DSRC road tolling system, is distinguished, for example, by a DSRC transceiver for DSRC communication with the DSRC OBUs of vehicles passing a fourth detection range, said DSRC transceiver providing a timestamp to the DSRC communication passed by each vehicle, wherein the evaluation device is additionally configured to determine a matching DSRC communication relative to the determined image from the timestamp of the DSRC communication and the fourth detection range.

A correspondingly preferred embodiment of the method according to the invention is distinguished by the following additional steps: performing DSRC communications with the DSRC OBUs of vehicles passing through the fourth detection range and providing a timestamp to each DSRC communication; and determining a matching DSRC communication relative to the determined image based on the timestamp of the DSRC communication and the fourth detection range.

In a DSRC road toll system, a DSRC OBU is used for DSRC communication with a roadside radio beacon (beacon) (roadside equipment, RSE). The DSRC communication end result is a toll transaction in a road toll system. Mobile monitoring platforms are also used to monitor vehicles with DSRC OBUs, which interrogate the DSRC OBUs of vehicles in the traffic stream to retrieve data from the DSRC OBUs for monitoring toll transactions occurring in the road toll system, or simply to check for the presence of an operational DSRC OBU in the vehicle. Such monitoring poses the additional problem that the transceiving range of the DSRC transceiver of the mobile monitoring device and the DSRC OBU of the monitored vehicle in the overlapping range necessary for its radio communication form a detection range that can be quite different from the detection range of the other sensors and cameras of the mobile monitoring device. This now leads to matching problems between DSRC radio communication on the one hand and images recorded for law enforcement purposes on the other hand. The present invention solves this problem by calculating the expected values of time and place when and where a vehicle with which DSRC communication has been performed is in the detection range of a camera, so as to enable an explicit matching of images and DSRC communication.

It should be appreciated that in this embodiment, the determination of the tachometer value may be only an intermediate result in the process of matching DSRC communications and images, i.e., not representing an output signal or result of the monitoring device or monitoring method itself, but merely used to calculate the expected value to match DSRC communications and images.

In fact, the speed of the vehicle may be measured in any manner known in the art. In accordance with a first preferred embodiment of the present invention, intended for use in a DSRC system, velocity is measured using the DSRC transceiver of the mobile monitoring device itself, i.e., preferably by means of doppler measurement of DSRC communications (i.e., an assessment of relative velocity-based doppler effects occurring in radio communications). Thus, in this embodiment, the first and fourth detection ranges are the same, since the tacho sensor is formed by the DSRC transceiver itself. As a result of this embodiment, it is not necessary to install a separate tacho sensor.

In an alternative preferred embodiment, also suitable for vehicles not equipped with a DSRC OBU, the speed is measured with the laser scanner of the mobile monitoring device or by evaluating two consecutive images of the camera.

Preferably, such a laser scanner can also be used to detect the geometric dimensions, for example the number of axles, length or height, of passing vehicles. For example, a laser scanner can emit a scanning beam onto a vehicle in a plane perpendicular to or at an angle to the direction of travel. From the number of axles or vehicle height detected in this way, the relevant geometry, for example the length, of the vehicle can be determined, for example from a table of the number of axles or vehicle height and the vehicle geometry generally associated therewith. Alternatively, the geometry measuring sensor may be constituted by a DSRC transceiver that receives vehicle data from the DSRC OBU as part of the DSRC communication, from which the DSRC transceiver calculates the geometry, preferably the length, of the vehicle, in which case the second and fourth detection ranges are the same. Furthermore, the data of the geometry sensor can also be used for further plausibility checks, such as determination of the vehicle volume, vehicle class, etc., against which plausibility of the match can be checked, the recorded images, the speed measurement values and/or the DSRC communication.

Drawings

Further features and advantages of the invention will become apparent from the following description of preferred exemplary embodiments, with reference to the attached drawings:

fig. 1-3 show a mobile monitoring device mounted on a monitoring vehicle for monitoring the vehicle in traffic at three different usage locations, fig. 1-3 simultaneously illustrating three phases of the method of the invention.

Detailed Description

Referring to fig. 1-3, a velocity v along a direction of travel 3 is shown, respectively₁A monitoring vehicle 1 moving on a lane of a road 2. The monitoring vehicle 1 is intended to monitor other vehicles 4 in the traffic flow on the road 2, said other vehicles 4 being, in the example shown here, in opposite directions of travel 5 at a speed v₂Moving on the reverse lane of the road 2 and driving past the monitoring vehicle 1 in the oncoming traffic stream. It should be understood, however, that the monitoring vehicle 1 may of course also monitor the vehicle 4 traveling in the same direction, or the vehicles 1 and/or 4 may be temporarily at a standstill in the stream of stop-and-go traffic. Different directions of travel 3 and 5 and velocities v of the monitored vehicle 1 and the monitored vehicle 4₁、v₂Time-varying conditions are created that make it impossible to monitor a strict geometric match between the vehicle 1 and the vehicle 4.

For monitoring the vehicle 4, the monitoring vehicle 1 carries a mobile monitoring device 6, the mobile monitoring device 6 comprising the following components, some of which may also coincide:

a first sensor 7 for measuring the relative speed v of the vehicle 4 with respect to the monitoring vehicle 1 when the vehicle 4 is located in the detection range 8 of the sensor 7, or is passing therethrough_r＝v₂-v₁；

A second sensor 9, the second sensor 9 at least indirectly measuring the geometric dimension of the vehicle 4, here the length L, when the vehicle 4 is located in the detection range 10 of the sensor 9;

at least one camera 11 for recording an image B of the vehicle 4 when the vehicle 4 is located in the detection range 12 of the camera 11 or is passing therethrough;

a (optional) DSRC transceiver 13, the DSRC transceiver 13 capable of radio communication 14 with an (optional) DSRC OBU 15 of the vehicle 4 when the vehicle 4 is located within a detection range 16 of the DSRC transceiver 13, or is passing therethrough;

the detection range 16 is the intersection of the transceiver range of the DSRC transceiver 13 and the transceiver range of the DSRC OBU 15; and

an evaluation device 17 connected to the above-mentioned components.

During operation, the sensor 7 measures the (relative) speed v of the passing vehicle 4_rAnd to each measured value v_rProvide and detect the velocity measurement value v_rCorresponding time stamp TS of time of₁. Knowing the natural speed v of the vehicle 1₁Can be determined by the relative velocity v_rInferring the natural speed v of the vehicle 4₂。

In the same way, the sensor 9 measures at least one geometric dimension, here the length L, of the passing vehicle 4 and provides each geometric dimension measurement L with a time stamp TS of the time at which it was detected₂. The camera 11 shoots the vehicle 4 passing through its detection range 12 and provides each recorded image 11 with a time stamp TS of the time at which the image was detected₃. Optionally, the DSRC transceiver 13 communicates 14 with the DSRC OBU 15 of a passing vehicle 4 and stores a time stamp TS with when the DSRC communication 14 was made₄Each of the DSRC communications 14.

The evaluation device 17 evaluates the time stamp TS by taking into account its corresponding time stamp TS₁-TS₄And detection ranges 8, 10, 12, 16, link the velocity measurements, geometry measurements, camera images and DSRC communications received from the sensors 5, 9, camera 11 and optional DSRC transceiver 13 so that they can match each other. Since the respective detection ranges 8, 10, 12 and 16 are known with respect to the coordinate system of the monitoring device 6, e.g. defined by solid angles, planes, sectors, etc., the respective times 15 are dependent on₁、15₂、15₃、15₄The occurring speed measurement, geometry measurement, camera image and/or DSRC communication can calculate the expected value of the location and time at which the passage of the vehicle attributable to the vehicle 4 occurs in the detection range 12 of the camera 11, so that in comparison therewith in the detection range 12, recorded with the camera 11 with its time stamp TS₃Image B of (1). Thus, even when the detection ranges 8, 12 of the speed sensor 7 and the camera 11 do not overlap, it is possible to determine the value v with respect to each of the measured speed values_rAnd vice versa. The vehicle geometry, in particular the number of axles a and/or the vehicle length L, is also evaluated therewith to exclude ambiguities, for example to verify a vehicle 4 recorded in an image B, or to distinguish several vehicles 4 recorded in the very same image B due to a dense traffic flow, on the basis of the length of the vehicle 4 detected in the image compared to the length L measured by the sensor 9.

In one embodiment, the velocity measurement v of the vehicle 4 determined in this way_rOr v₂Or may be used only as an intermediate result in the process of matching the DSRC communication 14 and recording the image B. Thus, knowing the detection range 16 of the DSRC transceiver 13, the velocity and geometry measurements of the sensors 7, 9, the detection ranges 8, 10, and the time stamp TS can also be made₁-TS₄And the DSRC communication of the vehicle 4 matches the corresponding image B of the vehicle 4. For this purpose, e.g. with corresponding time stamps TS₁-TS₄Evaluating a measured or calculated speed vector v of the vehicle 4 in connection with the detection ranges 8, 10, 11, 12, 16₂And monitoring the known velocity vector v of the vehicle 1₁To estimate or extrapolate the location and time at which the vehicle 4 with which the DSRC communication 14 occurred should appear in the detection range 12 of the camera 11 to match the image B of the camera 11 in which the time stamp TS of the vehicle 4 is recorded in the image B₃And the position is matched with these detection values.

Any sensor known in the art can be used for the tacho sensor 7 and the geometry measuring sensor 9. In a first embodiment, a laser scanner is used for the geometry measuring sensor 9, which sensor 9 emits a scanning beam, for example in a plane perpendicular or at an angle to the direction of travel, i.e. its detection range 10 is a plane, and scans the vehicle 4 by monitoring the movement of the vehicle 1 and/or the vehicle 4 in order to generate a 3D image of the vehicle 4.

Due to vehicle speed v₂For this reason, the vehicle length L is often represented with distortion in such a 3D image of the vehicle 4. In this case, the vehicle length L can thus be determined indirectly: thus, for example, from a correctly detected vehicle height (or vehicle volume), conclusions can be drawn about the specific class of vehicle, such as car, truck with trailer, etc., for which a specific typical vehicle length L can be determined. To this end, the sensor 9 may contain, for example, a table of typical vehicle heights and associated typical vehicle lengths, so that the appropriate length L of the vehicle 4 can be determined (if only approximately) from the measured vehicle heights.

As an alternative, the sensor 9 may be, for example, a 3D laser scanner which provides a 3D image matching the vehicle 4 very quickly like a photograph in one operation, from which 3D image the geometrical dimensions, such as the vehicle length L, can be determined directly.

Another alternative may be, for example, that the sensor 9 determines the number of axles a of the vehicle 4, for example using laser scanning or LIDAR or radar doppler measurements of the wheels of the vehicle 4. The sensor 9 may then again contain a table of vehicle lengths L or dimensions typical of a particular number of axles a, for example to determine relevant geometrical dimensions (if any approximation is true) such as the length L of the vehicle 4.

The speed sensor 7 can also be formed by a laser scanner, for example in the form of a LIDAR speed gun. Alternatively, the speed of the vehicle 4 can also be measured with a 2D or 3D laser scanner, for example by means of two very fast consecutive measurements and a determination of the local displacement of the vehicle 4 between the two measurements. The same laser scanner can then optionally be used for both the tacho sensor 7 and for the geometry measuring sensor 9.

In the substitutionIn an embodiment, the velocity may also be measured by means of an optional DSRC transceiver 13. To this end, Doppler measurements may be made for the DSRC communications 14, e.g., to determine the relative velocity v_r. Alternatively, the speed may be measured using the transceiver 13 with infrared emission during vehicle communication.

It is also contemplated that the DSRC OBU 15 measures its own velocity and sends the velocity to the DSRC transceiver 13 as part of the DSRC communication 14, including where the DSRC transceiver 13 constitutes a velocity sensor, as defined herein.

If the speed is measured with the DSRC transceiver 13, it will be appreciated that the first and fourth detection ranges 8 and 16 coincide.

Further, the DSRC transceiver 13 may also constitute the geometry measurement sensor 9 if, as part of the DSRC radio communication 14, the DSRC transceiver 13 receives vehicle data from the DSRC OBU 15 from which it can calculate the geometry, e.g., length L, of the vehicle 4. For example, the DSRC OBU 15 transmits information about the vehicle class or number of axles of the vehicle 4, from which information (again by means of a table of typical vehicle geometries for typical vehicle classes or numbers of axles) the relevant vehicle geometry can be calculated. If the geometry measuring sensor 9 and the DSRC transceiver 13 coincide, it will be appreciated that the detection ranges 10, 16 will of course coincide accordingly.

Alternatively, the transceiver 13 may be configured for short range transmission technologies other than DSRC, such as infrared or any desired microwave technology.

The invention is thus not limited to the embodiments described, but covers all variations and modifications falling within the framework of the appended claims.

Claims

1. Mobile monitoring device (6) for monitoring a vehicle (4), having:

a sensor (7) for measuring the speed of the vehicle (4) passing through a first detection range (8), a speed measurement value (v) of the vehicle passing through the sensor (7)_r) Providing Timestamps (TS)₁)；

A sensor (9) for at least indirectly measuring the geometry of a vehicle (4) passing through a second detection range (10), preferably the length of the vehicle (4), the sensor (9) providing a Time Stamp (TS) to the vehicle passing geometry measurement (L)₂)；

A camera (11) recording images (B) of vehicles (4) passing through the third detection range (12), said camera (11) providing a Time Stamp (TS) to each image (B) that a vehicle passes through₃) (ii) a And

an evaluation device (17) connected to the camera (11) and the sensor (7, 9), the evaluation device being configured to:

according to the velocity measurement value (v)_r) Time Stamp (TS) thereof₁) And a first detection range (8), and also according to the geometric dimensions measurement (L), the Time Stamp (TS) thereof₂) And a second detection range (10) for calculating a point and time at which the vehicle is expected to pass in the third detection range (12) to thereby obtain a Time Stamp (TS) from the image (B)₃) And a third detection range (12) for determining a matching image (B).

2. The mobile monitoring device of claim 1, the mobile monitoring device monitoring a DSRC OBU-equipped vehicle, further having:

a DSRC transceiver (13) in DSRC communication (14) with the DSRC OBU (15) of vehicles (4) passing a fourth detection range (16), the DSRC transceiver (13) providing a Timestamp (TS) to each DSRC communication (14) that each vehicle passes₄)；

Wherein the evaluation device (17) is further configured to communicate (14) the Time Stamp (TS) according to the DSRC₄) And a fourth detection range (16) for determining a matching DSRC communication (14) with respect to the determined image (B).

3. A mobile monitoring device according to claim 2, characterized in that the first and fourth detection ranges (8, 16) are identical and that the speed sensor (7) is constituted by a DSRC transceiver (13).

4. A mobile monitoring device according to claim 1 or 2, characterized in that the speed sensor (7) is constituted by a laser scanner.

5. The mobile monitoring device according to one of the claims 2 to 4, characterized in that the second and fourth detection ranges (10, 16) are identical and that the geometry measuring sensor (9) is constituted by a DSRC transceiver (13), as part of a DSRC communication (14), the DSRC transceiver (13) receiving vehicle data from a DSRC OBU (15), on the basis of which the DSRC transceiver (13) calculates the geometry, preferably the length (L), of the vehicle (4).

6. A mobile monitoring device according to one of claims 1 to 4, characterized in that the geometrical dimension measuring sensor (9) is formed by a laser scanner.

7. A mobile monitoring device as claimed in claim 6, characterized in that the laser scanner (9) detects the vehicle height or number of axles, from which it determines the relevant geometry, preferably the length (L), of the vehicle (4) from a table of vehicle heights or numbers of axles and relevant vehicle geometries.

8. A method of monitoring a vehicle, the method comprising the following steps in any desired sequence:

measuring the speed of the vehicle (4) passing through the first detection range (8) and comparing it with the measured speed value (v)_r) Providing Timestamps (TS)₁)；

At least indirectly measuring the geometry of the vehicle (4) passing through the second detection range (10), preferably the length of the vehicle (4), and providing a Time Stamp (TS) to said geometry measurement (L)₂)；

Recording images (B) of the vehicle (4) passing through the third detection range (12), and providing a Time Stamp (TS) to each image (B)₃)；

In addition, the method also comprises the following steps:

according to the velocity measurement value (v)_r) Time Stamp (TS) thereof₁) And a first detection range (8), and also according to the geometric dimensions measurement (L), the Time Stamp (TS) thereof₂) And a second detection range (10) for calculating a point and time at which the vehicle is expected to pass in the third detection range (12), and

whereby the time stamp (B) is based on the image (B)TS₃) And a third detection range (12) for determining a matching image (B).

9. The method of monitoring a vehicle as claimed in claim 8, said vehicle being equipped with a DSRC OBU, further having the steps of:

performing DSRC communications (14) with the DSRC OBUs (15) of the vehicle (4) passing through the fourth detection range (16), and providing a Timestamp (TS) to each DSRC communication (14)₄) (ii) a And

time Stamp (TS) from DSRC communications (14)₄) And a fourth detection range (16) for determining a matching DSRC communication (14) with respect to the determined image (B).

10. The method of claim 9 wherein the first and fourth detection ranges (8, 16) are the same and the velocity (v) is measured using doppler measurements of DSRC communications (14)_r)。

11. Method according to claim 8 or 9, characterized in that the speed is measured with a laser scanner or by evaluation of two successive images of the camera.

12. The method according to one of the claims 9 to 11, characterized in that the second and fourth detection ranges (10, 16) are identical and as part of the DSRC communication (14) vehicle data from the DSRC OBU (15) is received, from which data the geometry, preferably the length (L), of the vehicle (4) is calculated.

13. Method according to one of claims 8 to 11, characterized in that the geometrical dimensions are measured with a laser scanner (9).

14. Method according to claim 13, characterized in that the vehicle height is detected with a laser scanner (9) and from said vehicle height, the relevant geometry, preferably the length (L), of the vehicle (4) is determined from a table of vehicle heights and relevant vehicle geometries.

15. Method according to one of claims 8 to 14, characterized in that the method is carried out from a monitoring vehicle (1) in motion.