EP3128495B1 - Method for geographical area detection of transportation infrastructure - Google Patents

Description

FIELD OF THE INVENTION

The invention relates to a method for geographical area detection of traffic infrastructure according to the preamble of claim 1.

This method is suitable for use in what are known as roadside units (referred to below as receiving units), it being possible for these roadside units to be part of a cooperative system.

STATE OF THE ART

Cooperative systems in connection with transport infrastructure are the subject of intensive current research and development. They are intended to enable road operators, transport infrastructure, vehicles and their drivers, and other road users to cooperate with one another in order to enable the most efficient, safe and pleasant journey possible.

For this purpose, systems are provided that enable communication in the form of data exchange between vehicles and infrastructure. Such communication systems are known, for example, under the acronyms V2R (Vehicle to Roadside) or V2V (Vehicle to Vehicle). These communication systems are abbreviated as ITS-G5 in Europe and as DSRC/WAVE in the USA.

The present invention relates to the field of V2R communication, in which what are known as Common Awareness Messages (CAM) are usually transmitted from the vehicles participating in road traffic to receiving units in the infrastructure, what are known as Road Side Units (R-ITS). This CAM can contain a wide variety of traffic-related data, such as information about the current position and speed of the transmitting vehicle, including the associated time of measurement.

This data is usually collected by the receiving units, evaluated and forwarded to higher-level traffic control centers. Finally, macroscopic data averaged over certain route and time sections are analyzed there, such as traffic densities or travel speeds in certain route sections. Traffic jam or accident warnings can also be generated and issued in this way.

The communication between vehicles on a certain route section and the receiving unit that monitors this section essentially takes place continuously, i.e. with high frequency of the CAM transmissions. The V2R communication begins when the vehicle enters the detection area of a receiving unit and ends when it leaves this detection area. Since the distance that a vehicle usually covers within such a detection area is around 1 km, and since several routes (different lanes or lanes of lanes) can often be driven on within this detection area, it is sometimes advantageous to use the entire detection area into several sections subdivide within which the collected data is averaged and processed for transmission to the higher-level traffic control centers.

To do this, it was previously necessary to record the geographical topology of the traffic area manually in each case before the receiving unit was put into operation, to configure it in the receiving unit and to define the corresponding sections into which the entire recording area is to be divided. Such a configuration and detection is very time-consuming, therefore expensive, and must be carried out very precisely. In addition, this process must be repeated each time the external conditions change (e.g. after conversion work) or when the receiver unit is used in a different section of the route.

DE 10 2013 227144 A1 discloses a method according to the preamble of claim 1.

OBJECT OF THE INVENTION

It is therefore an object of the present invention to provide a method in the form of a learning algorithm for a receiving unit of a cooperative system, which makes manual detection and configuration of the receiving unit obsolete and is simple enough to be executed directly on the receiving unit.

PRESENTATION OF THE INVENTION

• Zustandsdaten von mehreren Fahrzeugen, welche Zustandsdaten jeweils zumindest eine Position des jeweiligen Fahrzeuges sowie gegebenenfalls einen Zeitpunkt der Positionsbestimmung umfassen, werden von den Fahrzeugen mehrmals während die Fahrzeuge den Erfassungsbereich der Empfangseinrichtung durchqueren, mittels drahtloser Kommunikation an die Empfangseinheit übermittelt;

wird die Aufgabe der Erfindung dadurch gelöst, dass das Verfahren die folgenden weiteren Schritte umfasst:

• die Empfangseinheit ermittelt aus den übermittelten Zustandsdaten für jedes Fahrzeug die erste empfangene Position im Erfassungsbereich und die letzte empfangene Position im Erfassungsbereich;
• die Empfangseinheit, oder eine mit der Empfangseinheit verbundene Recheneinheit, berechnet für jedes Fahrzeug einen Vektor, wobei sich der Vektor von der ersten empfangenen Position des Fahrzeuges im Erfassungsbereich bis zu der letzten empfangenen Position des Fahrzeuges im Erfassungsbereich erstreckt;
• aus den Vektoren aller Fahrzeuge bestimmt die Empfangseinheit oder Recheneinheit Fahrtrichtungen der Fahrzeuge sowie die geographische Lage von Fahrbahnen und/oder Spuren der Fahrbahnen der Verkehrsinfrastruktur im Erfassungsbereich.

In a method according to the invention for geographical area detection of traffic infrastructure by means of a receiving unit arranged in the area of the traffic infrastructure for a detection area of the receiving unit, which comprises the following steps:

• Status data from a number of vehicles, which status data each include at least one position of the respective vehicle and possibly a point in time of the position determination, are transmitted by the vehicles to the receiving unit several times by means of wireless communication while the vehicles are crossing the detection range of the receiving device;

the object of the invention is achieved in that the method comprises the following further steps:

• the receiving unit determines from the transmitted status data for each vehicle the first received position in the detection area and the last received position in the detection area;
• the receiving unit, or a computing unit connected to the receiving unit, calculates a vector for each vehicle, the vector extending from the first received position of the vehicle in the detection area to the last received position of the vehicle in the detection area;
• From the vectors of all vehicles, the receiving unit or computing unit determines the directions of travel of the vehicles and the geographic location of lanes and/or lanes of lanes of the traffic infrastructure in the detection area.

This provides a method by means of which the topology of the traffic flows within the detection range of the receiving unit can be determined and the topology of the streets monitored by the receiving unit (in particular and the traffic infrastructure in general) can be inferred. Manual recording of the topography and configuration of the receiving unit is therefore no longer necessary. Especially in connection with mobile receiving units, which are used at constantly changing locations, the method described therefore implies a considerable saving in costs and working time.

The arithmetic work required for capturing the topography can be carried out either by the respective receiving unit itself or by arithmetic units which are connected to the receiving units, for example by means of wireless communication. Such a processing unit can, for example, be a computer located at some distance from the receiving unit, for example the central computer of the cooperative system.

In addition, there is the advantage that the method can be carried out several times, preferably periodically, as a result of which inaccuracies in the positions of the vehicles, which are usually determined from GPS measurements that are subject to a certain scatter, can be compensated for.

When determining the vector of a vehicle, the first position of the vehicle (when entering the reception area) is selected as the origin of the vector and the last position of the vehicle (before leaving the reception area) in the reception area of the receiver unit is selected as the end point of the vector. Such a vector should approximately represent the movement of the vehicle in the reception area.

In a preferred embodiment of the method according to the invention, it is provided that the directions of travel of the vehicles are determined by the vectors of all vehicles are grouped according to an angle which the respective vector encloses with a reference vector.

This provides a particularly simple and computationally uncomplicated method for determining the directions of travel of the vehicles. The calculation of the angle between the respective vector of the vehicle and the reference vector can be determined, for example, by calculating the scalar product of the two vectors. Then all vectors are divided into clusters, the number of which corresponds to the number of directions in which the detected traffic flows are moving.

It can be provided that when determining the directions of travel of the vehicles, a specific angle range is assigned to a specific direction of travel.

A full angle (2π) can be divided into two areas, for example, namely a first area (between 3π/2 and π/2) and a second area (between π/2 and 3π/2). Depending on which of the two areas the angle of a specific vector falls in, one of two directions is now assigned to the assigned vehicle. In the case of a four-lane motorway (two lanes in each direction), there would be two clusters of vectors - one cluster in each direction. More complicated topologies would require further subdivisions of the full angle.

In addition, it can be provided that the lanes and/or lanes of the lanes of the traffic infrastructure are determined by grouping the vectors of all vehicles according to a normal distance of the receiving unit from the respective vector.

This classification of the vectors according to their respective normal distance from the receiving unit leads to a higher local resolution of the individual traffic flows. If the vectors of the vehicles on the four-lane motorway given above as an example were previously only assigned to one of two clusters (one cluster per direction of travel), this preferred embodiment of the method according to the invention leads to an assignment of a vector to one of a total of four clusters - one Clusters per lane of the highway.

In a preferred embodiment of the method according to the invention, it is provided that for each roadway and/or lane of the roadways, an average entry point and an average exit point of those vehicles driving on this lane or lane are determined.

If the number of vehicles involved in the process is high enough, these averaged entry and exit points correspond to a good approximation to the center of the respective lane or lane of the lane. The connection between the detected traffic flows within the detection range of the receiving unit and the topology of the traffic infrastructure monitored by the receiving unit is thus established.

In a preferred embodiment of the method according to the invention, it is provided that the status data is recorded by the vehicles.

Devices provided specifically for status data acquisition are therefore superfluous. For example, status data acquisition using GPS technology has the additional advantage that equipment usually present in vehicles, such as navigation systems or mobile phones, can be used to record the status data. Of course, other navigation systems can also be used, such as Galileo.

The use of widespread and established technologies is also a fundamental idea of the concept of cooperative systems, since such systems only make sense if as many road users as possible communicate with each other. The data recorded by the vehicles is preferably also transmitted to the receiving unit using widespread wireless communication technologies such as ITS-G5, DSRC/WAVE, mobile radio or WLAN.

In a further preferred embodiment of the method according to the invention, provision is made for the status data to be transmitted to the receiving unit periodically, e.g. at a frequency of 0.1 Hz to 100 Hz.

Depending on the size of the respective detection area and the average speed of the vehicles driving on the traffic infrastructure in this area, the frequency of the status data transmission is preferably selected so that the positions identified as the first or last received position of the vehicles are as good as possible correspond to the actual points of entry and exit of the vehicles into and out of the detection area of the receiving unit.

In a preferred embodiment of the method according to the invention, it is provided that the position of the vehicle received last is that position of the vehicle after which no further status data of this vehicle has reached the receiving unit for a specified period of time.

Again, this is a particularly simple method associated with little computational effort to determine the position of the vehicle that was last received. After a certain period of time has elapsed, preferably related to the frequency of the status data transmission, that position of the vehicle which was contained in the last received status data of the vehicle is identified as its last received position. The higher the frequency of data transmission, the greater the probability that the vehicle's last received position matches the position at which the vehicle leaves the detection area.

In a preferred embodiment of the method according to the invention, it is provided that the accuracy of the method is increased by using additional topology information.

In particular, it is provided that information about the topology of the traffic infrastructure from other sources is used in order to increase the accuracy of the geographic area identification. For example, information from mobile phone networks transmitted via MAP telegram could be included.

In a preferred embodiment of the method according to the invention, it is provided that the receiving unit or computing unit divides the maximum detection range into a number of sections.

In particular for the regular operation of the receiving unit after the calibration, this preferred embodiment provides for the subdivision of the receiving area into a number of sections. In the case of the example of the four-lane motorway, the reception area can be subdivided in such a way that each lane is assigned its own section. In addition, it is also possible to subdivide the individual lanes into further sections perpendicular to the direction of travel, which is particularly useful when the detection area is particularly large and/or when the topology of the traffic infrastructure to be detected is particularly complicated. These sections then serve as areas within which certain status data are averaged during normal operation of the receiving unit after calibration.

• die Empfangseinheit ausgebildet ist, um Zustandsdaten von mehreren Fahrzeugen, welche Zustandsdaten jeweils zumindest eine Position des jeweiligen Fahrzeuges sowie gegebenenfalls einen Zeitpunkt der Positionsbestimmung umfassen und von den Fahrzeugen mehrmals während die Fahrzeuge den Erfassungsbereich der Empfangseinrichtung durchqueren mittels drahtloser Kommunikation an die Empfangseinheit übermittelt werden, zu empfangen, und
• die Empfangseinheit ausgebildet ist, um aus den übermittelten Zustandsdaten für jedes Fahrzeug die erste empfangene Position im Erfassungsbereich und die letzte empfangene Position im Erfassungsbereich zu übermitteln;
• die Empfangseinheit, oder eine mit der Empfangseinheit verbundene Recheneinheit, ausgebildet ist, um für jedes Fahrzeug einen Vektor zu berechnen, wobei sich der Vektor von der ersten empfangenen Position des Fahrzeuges im Erfassungsbereich bis zu der letzten empfangenen Position des Fahrzeuges im Erfassungsbereich erstreckt, und
• die Empfangseinheit oder die Recheneinheit ausgebildet ist, um aus den Vektoren aller Fahrzeuge Fahrtrichtungen der Fahrzeuge sowie die geographische Lage von Fahrbahnen und/oder Spuren der Fahrbahnen der Verkehrsinfrastruktur im Erfassungsbereich zu bestimmen.

In addition, a receiving unit is provided for use in one of the methods described above, wherein

• the receiving unit is designed to receive status data from a number of vehicles, which status data each include at least one position of the respective vehicle and, if applicable, a point in time of the position determination and are transmitted by the vehicles to the receiving unit several times by means of wireless communication while the vehicles are crossing the detection range of the receiving device received, and
• the receiving unit is designed to transmit the first received position in the detection area and the last received position in the detection area from the transmitted status data for each vehicle;
• the receiving unit, or a computing unit connected to the receiving unit, is designed to calculate a vector for each vehicle, the vector extending from the first received position of the vehicle in the detection range to the last received position of the vehicle in the detection range, and
• the receiving unit or the computing unit is designed to determine the travel directions of the vehicles and the geographical location of lanes and/or lanes of the lanes of the traffic infrastructure in the detection area from the vectors of all vehicles.

Such a receiving unit according to the invention is suitable for functioning as a receiving unit in one of the methods described above.

Furthermore, a computer program product is provided which comprises a computer program and can be loaded directly into a memory of the receiving unit described above, or into the memory of a computing unit assigned to the receiving unit, with computer program means in order to carry out all the steps of the method according to the invention if the computer program is Receiving unit, or the computing unit is running.

Since the method according to the invention is a method in the context of which large amounts of data may have to be processed, an implementation of the method as a computer program makes sense.

BRIEF DESCRIPTION OF THE FIGURES

Fig. 1

eine schematische Darstellung einer Verkehrsinfrastruktur in Form einer vierspurigen Autobahn welche von einer erfindungsgemäßen Empfangseinheit überwacht wird.

The invention will now be explained in more detail using an exemplary embodiment. The drawing is an example and is intended to explain the idea of the invention, but in no way restricts or even exhaustively reproduces it. It shows:

1

a schematic representation of a traffic infrastructure in the form of a four-lane highway which is monitored by a receiving unit according to the invention.

WAYS TO CARRY OUT THE INVENTION

1 shows a traffic infrastructure in the form of a section of a four-lane motorway. The section of the motorway shown has two lanes 7 on which lanes 7 vehicles (not shown) move in one direction 6 each. Each roadway 7 has two lanes 8 each.

A receiving unit 1 is arranged in an area between the two lanes 8 . In the specific case, a detection area 2 of the receiving unit 1 is approximately circular and covers a substantial part of each of the two lanes 8.

Four vectors 3 are shown within the detection area 2, each of which extends from a position 4 received as the first to a position 5 of a vehicle received as the last. Each of the vectors 3 encloses a specific angle 10 with a reference vector 11 . Each vector 3 has a normal distance 12 from the receiving unit 1 .

In the specific case, the overtaking lane 8 of the upper lane 7 is divided into seven sections 9 . An average entry point 13 and an average exit point 14 are shown for two vectors 3 of the right lane 8 of the lower lane 7 .

HOW THE INVENTION WORKS

The receiving unit 1 in FIG. 1 is a receiving unit according to the invention, which runs a computer program to determine the geographical position of the roadways/lanes.

On the upper and lower roadway 7 of the motorway section shown in FIG. 1, vehicles are moving in one of a total of two possible directions of travel 6. Two lanes 8 are available on each roadway 7 for this purpose.

According to the invention, it is provided that several of these vehicles transmit status data to the receiving unit 1 several times while they are crossing the detection area 2 of the receiving unit 1 . This transmission of status data to the receiving unit 1 typically takes place at a frequency of approximately 10 Hz, but depending on the technology or device used in the vehicles for data transmission, frequencies that are significantly below this typical value are also possible.

The frequency with which the status data is measured in the vehicles influences the quality of the area detection according to the method to a certain extent. The higher this frequency, especially the frequency of Position measurement is, the closer are the position 4 received as the first and the position 5 received as the last of the vehicle to that position at which the vehicle enters the detection area 2 of the receiving unit 1 or leaves the detection area 2 again.

This status data contains at least a position of the vehicle and possibly the time of the measurement. However, it is also conceivable that the receiving unit 1 logs the time at which status data of the vehicle was transmitted and the status data does not include a time at which the position was measured.

In the specific exemplary embodiment, the status data is recorded by means of GPS and the status data is transmitted to the receiving unit 1 by means of ITS-G5 communication.

After the status data of N vehicles has been transmitted to the receiving unit 2 within a predetermined detection time period, the receiving unit 1 evaluates the status data of the N vehicles by carrying out the next method steps. However, the transmission and reception of status data from following vehicles can continue in parallel or can also be interrupted.

From the status data transmitted by the vehicles to the receiving unit 1, the receiving unit now determines for each vehicle the first position 4 received, which is identified as the position of the vehicle that is contained in the first status data transmission of the respective vehicle, as well as the last position received Position 5 of the vehicle. The latter is called identifies that position of the vehicle which is contained in the last status data transmission of the vehicle before the vehicle has left detection area 2 again.

The vector 3 is now calculated for each vehicle, which extends from the position 4 received as the first to the position 5 of the respective vehicle received as the last. For N vehicles that have crossed the detection area 2 during the detection period, there are now N vectors 3 .

Next, the receiving unit 1 calculates the angle 10 which each of the vectors 3 forms with the reference vector 11 . This can be accomplished, for example, by calculating the scalar product of the respective vector 3 with the reference vector 11. The reference vector 11 is of course always the same for all angle calculations.

Angular ranges are now determined according to which the N vectors 3 are subdivided according to their respective angle 10 . In the specific example, one of the four vectors 3 shown has an angle 10 in the range between 3π/2 and π/2 (first angle range), and three vectors 3 each have an angle 10 which is in the range between π/2 and 3π/2 (second angular range) is located.

According to this subdivision, the vector 3, whose angle 10 is in the first angle range, is assigned the first direction of travel 6 - and thus the upper roadway 7 - and the other three vectors 3, whose angle 10 is in the second angle range, are assigned the other direction of travel 6 - and thus the lower lane 7.

There are now two clusters of vectors 3, with N ₁ vectors 3 being assigned to the first cluster and N ₂ vectors 3 being assigned to the second cluster, and with N ₁ + N ₂ = N Clusters sweep, the geographic location of lane 7 fixed.

The normal distance 12 between the respective vector 3 and the receiving unit 1, or any other reference point, is now calculated for all vectors 3 in one of the two clusters. Normal distance ranges are then determined, according to which the vectors 3 of this cluster are further subdivided according to their respective normal distance 12 .

Considering, for example, the set N ₂ of the vectors 3 assigned to the second cluster in the specific exemplary embodiment, one vector 3 has a shorter normal distance 12 and two vectors 3 have a longer normal distance 12 . Correspondingly, the second cluster itself is divided into two subclusters with N ₂ ' vectors 3 in the first subcluster and N ₂ " in the second subcluster, where N ₂ ' + N ₂ "=N ₂ .

The first cluster (the upper lane 7) of the specific exemplary embodiment is treated analogously, but only one vector 3 is shown in the specific example.

A lane 8 of the lane 7 associated with the respective cluster is now assigned to the subclusters of a cluster.

In order to now learn from the traffic flows completely recorded during the recording period within the recording area 2 In order to be able to deduce the geographical location of the corresponding traffic infrastructure, a further procedural step is required, which can look like this: From the set of vectors 3 assigned to a specific subcluster - and thus to a specific lane 8 of a roadway 7 - the averaged entry point 13 and the average exit point 14 of all vehicles assigned to this subcluster is determined.

In the specific exemplary embodiment, this is shown for the two subclusters N ₂ " of the second cluster N _2. These averaged entry 13 and exit points 14 are now identified with those points at which the vehicles enter the section of the track assigned to the subcluster of the cluster 8 or leave this section of the track 8. A vector can now be formed between these two averaged entry 13 and exit points 14, which vector represents the modeled course of the corresponding track 8.

The entire detection area 2 of the receiving unit 1 can thus be subdivided into sections 9 . On the one hand, the lanes 8 or lanes 7 of the traffic infrastructure that have just been determined are suitable for this. On the other hand, it is also possible to subdivide individual route sections, such as the overtaking lane 8 of the upper roadway 7, into further longitudinal sections 9. During normal operation of the receiving unit 1, these sections can be used to assign the status data, which are constantly transmitted from the vehicles in the detection area 2 to the receiving unit 1, not to a specific position but to one of these sections 9 and then all status data assigned to this section 9 to average the respective section 9.

REFERENCE LIST

1

receiving unit

2

detection range

3

vector

4

as the first position received

5

as the last position received

6

driving direction

7

roadway

8th

Lane of lane 7

9

one of the N sections (longitudinal sections) of track 8

10

angle

11

reference vector

12

normal distance

13

average entry point

14

average exit point

Claims (12)

1. Method for geographic region detection of traffic infrastructure by means of a receive unit (1) disposed in the region of the traffic infrastructure for a detection region of the receive unit, wherein the method comprises the following steps:

   - Status data of a number of vehicles, which status data in each case includes at least a position of the respective vehicle and if necessary a time at which the position was determined, is communicated by the vehicles several times to the receive unit (1) in the period during which the vehicles are passing through the detection region (2) of the receive unit (1) by means of wireless communication;

   wherein the method is characterised in that it comprises the following further steps:

   - The receive unit (1) determines the first position received in the detection region and the last position received in the detection region for each vehicle from the transmitted status data;

   - The receive unit (1), or a processing unit connected to the receive unit, computes a vector (3) for each vehicle, wherein the vector (3) extends from the first position (4) of the vehicle received in the detection region to the last position (5) of the vehicle received in the detection region;

   - From the vectors (3) of all vehicles the receive unit (1) or processing unit determines directions of travel (6) of the vehicles as well as the geographic location of roadways (7) and/or lanes (8) of the roadways (7) of the traffic infrastructure in the detection region (2).
2. Method according to claim 1, characterised in that the directions of travel (7) of the vehicles are determined by the vectors (3) of all vehicles being grouped in accordance with an angle (10) that the respective vector (3) makes with a reference vector (11).
3. Method according to claim 2, characterised in that, when the directions of travel (7) are determined, the vehicles are each assigned a specific range of angles of a specific direction of travel (7).
4. Method according to claim 2 or 3, characterised in that the roadways (7) and/or lanes (8) of the roadways (7) of the traffic infrastructure are determined by the vectors (3) of all vehicles being grouped in accordance with a normal distance (12) of the receive unit (1) from the respective vector (3).
5. Method according to claim 4, characterised in that, for each roadway (7) or lane (8) of the roadways (7) an averaged entry point (13) as well as an averaged exit point (14) of those vehicles that are driving along this roadway (7) or lane (8) is determined.
6. Method according to one of claims 1 to 5, characterised in that the status data is detected by the vehicles.
7. Method according to one of claims 1 to 6, characterised in that the status data is communicated periodically to the receive unit (1).
8. Method according to one of claims 1 to 7, characterised in that the position received as the last position (5) of the vehicle is the position for which, after it has been communicated to the receive unit (1), no further status data of this vehicle has reached the receive unit (1) for a defined period.
9. Method according to one of claims 1 to 8, characterised in that the accuracy of the method is increased by the use of additional topology information.
10. Method according to one of claims 1 to 9, characterised in that the receive unit (1) or processing unit divides the maximum detection region (2) into a number of segments (9).
11. Receive unit (1) for use in a method according to one of claims 1 to 10, wherein

    - The receive unit (1) is embodied to receive status data from a number of vehicles, which status data includes in each case at least a position of the respective vehicle and also if necessary a time at which the position was determined and which is communicated by wireless communication to the receive unit (1) a number of times by the vehicles while the vehicles were passing through the detection region (2) of the receive unit (1),

    characterised in that

    - The receive unit (1) is embodied to determine the first position received in the detection region and the last position received in the detection region for each vehicle from the status data communicated;

    - The receive unit (1), or a processing unit connected to the receive unit, is embodied to calculate a vector (3) for each vehicle, wherein the vector (3) extends from the first position of the vehicle received in the detection region (2) to the last position (5) of the vehicle received in the detection region (2), and

    - The receive unit (1) or processing unit is embodied to determine, from the vectors (3) of all vehicles, directions of travel (6) of the vehicles as well as the geographic position of roadways (7) and/or lanes (8) of the roadways (7) of the traffic infrastructure in the detection region (2).
12. Computer program product, which comprises a computer program and is able to be loaded directly into a memory of a receive unit (1) or a processing unit assigned to the receive unit (1), with computer program means for executing all steps of the method according to one of claims 1 to 10 when the computer program is executed by the receive unit (1) or by the processing unit.

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