EP0962004B1 - Device and method for reporting traffic jams - Google Patents

Abstract

The invention relates to a method and device for reporting traffic jams comprising means for receiving traffic data picked up by sensors. The inventive method provides means for calculating output data describing the extent of traffic jams on the basis of traffic data received using a valid traffic flow density diagram for the traffic route concerned.

Description

The invention relates to a device for information about Traffic disturbances with means for receiving with sensors recorded traffic data and a method for Information about traffic disruptions.

To inform motorists have been around for a long time Spoken traffic announcements known. These are with various disadvantages, for example with Delays and inaccuracies caused by manual and thus also subjective acceptance and transmission of the Information is connected. For example, it happens before a driver gets stuck in a traffic jam that (still) was not announced, or that despite the traffic jam warning relevant road when it arrives at the designated Site can drive realistically without problems.

A more precise recording and faster transmission has become known with the help of the Systems for the transmission of digitally coded traffic reports become possible. The structure and coding of these Traffic reports and the list of places are in CEN pr ENV / 278/7/1/0012 and pr ENV / 278/7/3/0004 set on the proposed standard ALERT C, June 1996, published by the RDS ATT ALERT Consortium. The essential elements A traffic announcement is the location of the event (Location) and the event (Event). These details are cataloged, that is, every traffic-relevant place and a unique code for every traffic-relevant event is assigned. The concatenation of the locations in the location table along existing roads shows the course. Except the usual facilities of a receiving device with a RDS decoders are used to use the traffic information channel TMC (Traffic Message Channel) Decoding devices for Storage, processing and output of the Traffic announcements required.

Digitally coded traffic reports - also in the following Called TMC messages - can with the radio data system (RDS), which is an additional and inaudible Transmission of digital data in parallel with Broadcast programs in a data channel. Specifications of the radio data system for FM radio are among others in the publication Tech. 3244-E, March 1984 of the European Runfunk Union (EBU). Radio receivers with suitable RDS decoders can transmitted data in addition to audio reception with the Record and decode the same receiver.

Digitally coded traffic reports can also be passed on to others Way than via broadcasters and radio data signals be transmitted. This is, for example, a transmission of digitally coded traffic reports via mobile radio networks possible. With GSM (Global System for Mobile Communication) parallel to the language of short messages (Short Messages) are transmitted, which are also digitally coded May contain traffic reports.

These known systems are primarily used for Transmission of traffic reports, however, messages are included other content not excluded, for example general hazard warnings. Through digital coding is a processing of the received data before the output possible, for example a selection by area or Roads.

Even with such a system, the input data in the are essentially generated by sensors Not misjudging the information provided excluded. So they leave with the known systems output information only limited conclusions on the despite traffic disruption possible speed or on the Duration of a traffic disruption.

DE 31 28 578 A1 describes a method for automatic Traffic jam detection and traffic jam forecast known become. To this end, it is proposed the form of the Speed distribution of vehicles with one Compare the reference curve. Regardless of exogenous There is a risk of traffic jams if the Speed distribution from the reference curve in essential points deviates. This information becomes used, for example, on the roadside Means of communication, such as warning signs, on the risk of traffic jams to point.

The object of the present invention is therefore that Drivers don't just have static information accessible too make but information that draws conclusions on the Allow actual traffic obstruction, for example the temporal development of a traffic disruption or the achievable despite traffic disruption Average speed on the affected Stretch.

This object is achieved with the device according to the invention solved in that means for the calculation of expenditure Data showing the impact of the traffic disruption describe from the traffic data received with the help one valid for the respective route section Flow density diagrams are provided.

The device according to the invention can in or in Connection with a terminal, for example one Car radio or a mobile device, or in a central Device be arranged. The one used for the calculation Flow density diagram is also often called Fundamental diagram of road traffic is called and is for example in "How a traffic jam develops", Spectrum of Science, 11/89, p. 182. It represents the connection of the traffic flow q - often also Called traffic strength - and the traffic density k. Um the data to be output using the flow-density diagram can calculate different sizes as input data used whatever is available from each standing sensors and the circumstances in individual cases depends. An advantageous embodiment of the invention is that the traffic data received each measured traffic density, an identifier of the affected Route section and the respectively measured extent of the Describe traffic disruption.

This embodiment can also be designed such that the traffic data received also for each Describe the route section of the valid flux density diagram. This has the advantage that a central traffic computer Flow density diagram to be taken into account in the calculation the current road conditions (e.g. single lane accessibility of a motorway). There the flux density diagram is a parabola, which is given by the Coordinate zero goes, a description suffices two sizes, for example by the coordinates of the Maximum.

Another advantageous embodiment of the invention Setup is that the traffic data received are extended TMC messages. This allows the existing facilities of the TMC system largely used become. Furthermore, there is a disturbance of existing ones Exclude TMC recipients.

An advantageous development of the invention Setup is that the data to be output is the average speed and / or travel time on one describe known route section. In addition or alternatively, according to another advantageous one Training should be provided that the data to be output describe the change in the length of the traffic disruption.

So a driver is much better than with the known information systems able to To respond to traffic disruptions, for example decide on which motorway exit an alternative route to choose.

Another development of the device according to the invention consists of data in the memory for description the flux density diagrams of sections of the route are stored are. This is for those sections of the route, for which have no temporary changes, one Transfer of the one describing the flux density diagram No data required. The storage of data for the "normal" flowcharts can be easily in the Relation to those for decoding TMC messages location tables required anyway.

To further facilitate the planning and implementation of Programs for long journeys are particularly important Calculation of route recommendations became known. Such Programs are for example for personal computers on the Available on the market or integrated into navigation systems. The User specifies start and finish, if necessary also others Waypoints, and then get either as a list or as Marking a route recommendation on a road map. Even if when calculating this route recommendation the Road condition and possibly existing ones Traffic disruptions can be considered unfavorable route calculation nevertheless take place, the Motorists get a route displayed that is only at a waypoint reached after a long time because of a now significantly increased traffic disruption than turns out wrong.

In another development of the invention The facility is therefore also a means of calculating Route recommendations are provided, with the calculated data to be output are taken into account.

In this development, it can be provided that the Establishment and means for calculating Route recommendations are arranged in a terminal that the traffic data from at least one central facility receives. This is just a uni-directional Data connection with the central device to the terminal required, such as in the radio data system or in the broadcast channel of a mobile radio system. alternative can be provided in this training that the Establishment and means for calculating Route recommendations arranged in a central facility are the data from end devices to a desired one Are feedable and from which the calculated Route recommendations to the end devices are transferable. This Further education uses a bidirectional data connection ahead, as used for example by mobile radio systems Will be provided.

The object of the invention is in a Method according to the invention for information about Traffic disruption, taking traffic data with the help of Sensors are recorded, solved that from the recorded traffic data using a for the each section of the current flow-density diagram Data to be output are calculated, which is the impact describe the traffic disruption.

The invention also includes a method of transmission of information about traffic disruption, being Traffic data can be recorded with the help of sensors which is provided that the recorded traffic data Are transmitted and there with the help of a for the each section of the current flow-density diagram data to be output from the transmitted traffic data be calculated, which is the impact of the traffic disruption describe.

By the measures listed in further subclaims are advantageous developments and improvements to method according to the invention possible.

Fig. 1

ein Blockdiagramm einer erfindungsgemäßen Einrichtung, die vorzugsweise in einem Endgerät angeordnet ist,

Fig. 2

und Fig. 3 Fluß-Dichte-Diagramme,

Fig. 4

ein Blockschaltbild einer Einrichtung gemäß einer Weiterbildung der Erfindung in einem Endgerät und

Fig. 5

in einer zentralen Einrichtung.

Exemplary embodiments of the invention are shown in the drawing using several figures and are explained in more detail in the following description. It shows:

Fig. 1

2 shows a block diagram of a device according to the invention, which is preferably arranged in a terminal,

Fig. 2

3 shows flux density diagrams,

Fig. 4

a block diagram of a device according to a development of the invention in a terminal and

Fig. 5

in a central facility.

Identical parts are given the same reference symbols in the figures Mistake.

The embodiment as well as parts of it are as Block diagrams shown. However, this does not mean that the device according to the invention on a realization with the help of individual ones corresponding to the blocks Circuits is limited. The device according to the invention is rather in a particularly advantageous manner with the help of highly integrated circuits possible. You can digital signal processors are used, which at suitable programming in the block diagrams perform the processing steps shown. The device according to the invention can be used together with other Circuit arrangements within an integrated circuit essential parts of a terminal, for example one Radio receiver, form.

In a receiver 1 are broadcast signals, the RDS signals included, received, including demodulation, Error correction and decoding of the RDS signals and a the TMC messages are then decoded. In addition, there is a device in the receiver 1 Selection of the TMC messages according to user-adjustable Selection criteria, for example according to individual streets and areas. The remaining TMC messages are then a selection filter 2, which with stores 3 to 5, 15 is connected for the location LOC, the extent EXT, the Characteristic values kmax, qmax of the flux density diagram, each current traffic density transmitted with the TMC message k and the also transmitted dimension 1 of the Traffic disruption. This information can be used for several TMC messages are saved.

At 7, the list of places 6 becomes the respective place (= Route section) stored FDD characteristic value kmax, qmax and read out the route length 1s. The route length is temporarily stored in a memory 8, while at 14 a Calculation of the FDD characteristic value in the event that Section of several FDD parameters in the location list are filed. This can be the case if for example, a section of the route partly four, partly six Has lanes. This calculation can be done as Minimum formation (worst value) or as Averaging takes place.

The FDD characteristic value thus calculated becomes 9 cached. At 10, a selection is made between the FDD characteristic value cached at 4 and 9. In this case, the transferred and buffered at 4 FDD parameter priority, so that the from the list of places 6 read out characteristic value is only used if none FDD characteristic value was transferred. This selection can also be made at 7 be hit by a dashed line is indicated. The result of the selection at 10 as well as the temporarily stored traffic density k and the extent 1 are evaluated at 11.

In detail, the evaluation can also be carried out using the 11 calculated flow-density diagram as below Described with reference to Figures 2 and 3, take place. The data to be output are then saved using a Output device (such as display) 12 made visible and / or e.g. available via voice output be put.

Figures 2 and 3 each show a flux density diagram, the relationship between traffic flow q and Represents traffic density k. The flow of traffic in Cars measured per unit of time, while traffic density k Cars per route unit means. The flux density diagram represents about a parabola that originates from the coordinates starting at kmax and qmax reached their maximum and then again until k = 2kmax and q = 0 drops. In Figures 2 and 3 three points A, B, C are highlighted for one low traffic density k1, a medium traffic density k2 and high traffic density k3.

The slope of the straight line shown in dashed lines in FIG. 2 gives the average speed of the vehicles. at that explained in connection with Fig. 1 Example were kmax and qmax for one transmit the specified route section as an FDD identifier, from which the complete curve is calculated. prevails for example, a traffic density on the route section k2, which is also transmitted to the terminal, the Traffic flow can be calculated. By dividing the Traffic flow through the traffic density is then the Slope of the straight line through point B and thus the Average speed calculated. Since the length 1 of the Traffic disruption was also transmitted from it again the time to go through the Traffic disruption affected part of the route section calculated and available by the output device 12 be put. Other results can also be displayed such as the delay compared to a trip at about "normal" speed or the time for the entire route section.

In Fig. 3, points A, B, C are tangents to the Flow density diagram created. The slope of these tangents gives the speed of density waves and the slope a secant, such as that between points A and B is the speed of Shock waves. Density waves settle on positive Slope of the tangents in the direction of travel, with negative Incline against the direction of travel, the latter thus influence the traffic that follows. This can be calculated whether a traffic disruption in a predetermined time a junction of a highway in Direction of travel or against the direction of travel.

Then, for example, a driver can decide or recommend a terminal, which connection point to the Leave or used to drive up.

Fig. 4 shows a device, which is also preferably in arranged a terminal and by a device 16 for Calculation of route recommendations is added. To this belongs to a memory 17 with a so-called digital Road map, which may also include the list of places 6 can be combined. With the help of a keyboard 18 User start, destination and if necessary intermediate Waypoints to be passed on the way enter. Of the device 16 is that in the receiver 1 selection of the TMC messages carried out controllable in such a way that all TMC messages that may be the calculation influence the route recommendation, be selected. For all of these TMC messages are the relevant data in the Save 3 to 5 and 15 filed.

The data belonging to each section of the route is retrievable from the device 16 from the memories, whereupon the result of the evaluation at 11 of the device 16 can be supplied. With that, in itself known route calculation traffic disruptions and their Effects are taken into account. For example be calculated whether a traffic disruption on one in itself recommended by the route calculation and by the vehicle A section of track to be reached later Represents impairment, so that possibly of another route is recommended in advance.

Fig. 5 shows a device according to the invention, which in a Central unit, for example in a central Traffic calculator, is arranged and in its main Components of the device of FIG. 4 corresponds.

Messages on individual sections of the route that are in the essentially the same information as for the already Illustrated embodiments are included via a Communication network 21, for example ISDN, from one 5 sensors 22 merely indicated in FIG. 5 fed. In memories 3 to 5 and 15 the data available for all sections of a route Road network stored so that the device 16 in the Is able to report all traffic disruptions at the Calculation of any route recommendations to be considered.

Requirements for calculating a route recommendation and the Route recommendations are calculated at the 5 via a mobile radio network 23 Transfer terminals 24. The keyboard 18 and the Display device 12 can for monitoring and Maintenance tasks are used.

Claims (16)

1. Device for informing a car driver about traffic disruption by radio having means for receiving traffic data which is picked up by sensors, characterized in that, in addition to the location (LOC) and the extent (EXT) of the traffic problem, the traffic density (k) is received in the receiver and stored, in that the maximum traffic density (kmax) is, as a function of the transmitted location (LOC), extracted from a memory (6) or else received and stored, in that in addition the maximum traffic flow (qmax) is, as a function of the transmitted location (LOC), extracted from the memory (6) or received, and in that means (11) are provided which describe the effect of the traffic disruption on the basis of the received traffic data taking into account the flow density diagram.
2. Device according to Claim 1, characterized in that the device additionally receives information relating to the spreading (1) of the traffic disruption.
3. Device according to one of the preceding claims, characterized in that the received traffic data comprises expanded TMC messages.
4. Device according to one of the preceding Claims 1 to 4, characterized in that the data to be output describes the average speed and/or the driving time on a known section of a route.
5. Device according to one of Claims 1 to 3, characterized in that the data to be output describes the change in the length of the traffic disruption.
6. Device according to one of Claims 4 to 5, characterized in that in addition means are provided for calculating route recommendations, the data to be output being taken into account.
7. Device according to Claim 6, characterized in that the device and the means for calculating route recommendations are arranged in a terminal which receives the traffic data from at least one central device.
8. Device according to Claim 7, characterized in that the device and the means for calculating route recommendations are arranged in a central device to which data in relation to a respectively desired journey can be fed by terminals and from which the calculated route recommendations can be transmitted to the terminals.
9. Method for informing a car driver about traffic disruption by radio, traffic data being picked up using sensors, characterized in that, in addition to the location (LOC) and the extent (EXT) of the traffic problem, the traffic density (k) is received and stored, in that the maximum traffic density (kmax) is, as a function of the transmitted location (LOC), extracted from a memory (6) or else received and stored, in that in addition the maximum traffic flow (qmax) is extracted from the memory (6) as a function of the transmitted location (LOC) or received, and in that the effect of the traffic disruption is described on the basis of the received traffic data taking into account the flow density diagram.
10. Method according to Claim 8, characterized in that the information relating to the spreading (1) of the traffic disruption is received.
11. Method according to one of Claims 8 to 10, characterized in that the received traffic data comprises expanded TMC messages.
12. Method according to one of Claims 9 to 11, characterized in that the data to be output describes the average velocity and/or the driving time on a known section of a route.
13. Method according to one of Claims 9 to 12, characterized in that the data to be output describes the change in the length of the traffic disruption.
14. Method for transmitting information relating to traffic disruption, traffic data being picked up using sensors, characterized in that, in addition to the location (LOC) and the extent (EXT) of the traffic problem, the traffic density (k) is transmitted, in that the maximum traffic density (kmax) is preferably also transmitted, in that the maximum traffic flow (qmax) for the section of the route is transmitted, and in that the effect of the traffic disruption is determined on the basis of the received traffic data taking into account the flow density diagram.
15. Method according to Claim 14, characterized in that information relating to the spreading of the traffic disruption is transmitted.
16. Method according to one of Claims 14 to 15, characterized in that the transmitted traffic data comprises expanded TMC messages.

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