EP2704120A1 - Method for determining traffic information - Google Patents

Abstract

The method involves providing road-side measuring points (MP1-MP3) along a traffic area (VB) to be monitored, where the measuring points are provided by respective measurement units (ME1-ME3), which are provided as sound transducers i.e. microphones. Vehicle noise (FG) is detected (1) by each measurement unit over a measurement time period. The detected vehicle noise is analyzed and evaluated (2) based on a comparative data. Parameters for a traffic flow and/or a weather-related state of a road surface of the traffic area to be monitored are derived (4) based on the analysis of vehicle noise. The weather-related state consists of local rainstorms, snow and/or freezing states.

Description

Technical area

The present invention relates generally to the field of traffic engineering. More particularly, the present invention relates to a method for determining traffic information and traffic monitoring. In this case, along a traffic area to be monitored, such as e.g. Highway, highways, etc. roadside measuring points arranged and provided these measuring points measurement units.

State of the art

In recent years, a number of vehicles (passenger cars and trucks) in road traffic and thus a traffic density have increased greatly. Therefore, the traffic is particularly on highways such. Highways, expressways, etc. heavily compressed. For optimizing or optimally controlling a traffic flow, it is necessary to have or make available, as far as possible, information about a current traffic situation and a road condition (for example icing, snow track, rain, etc.) as part of the traffic information. The traffic situation is an actual state of one or more traffic areas, in which a vehicle density or traffic density, traffic obstructions, but also a weather situation is taken into account by the corresponding traffic routes and modes of transport.

A respective current traffic situation is determined on the basis of traffic data and information, for example in a traffic control center, which are usually obtained from roadside arranged measuring sections or measuring points. A measuring cross section is, for example, by a mostly stationary traffic detector such as by induction loops, infrared sensors, radar sensors and / or optical sensors (eg video camera), formed. From such traffic detectors usually time-related counts, occupancy, traffic, speeds and the like of the measuring cross section or measuring point passing vehicles are then determined, collected and delivered to the traffic control center, for example. However, this approach requires a high infrastructural effort for installation, operation and maintenance, in particular of the measuring cross sections or measuring points, especially for a nationwide determination of traffic information. Furthermore, in this approach, only limited information about a traffic condition affecting the road condition (eg ice, snow, etc.) is determined.

From the Scriptures DE 10 2009 049 382 A1 For example, a system for determining traffic density and dynamics is known in which emissions existing by road traffic, in particular longitudinal pressure waves and shocks, as well as weather values (eg temperature, air humidity, etc.) are absorbed by corresponding sensors. These measurement data are then analyzed by means of partially complex mathematical methods and from this a current state of the road traffic is derived. A problem with that in writing DE 10 2009 049 382 A1 This means that a large number of different sensors must be installed at the respective measuring points for a comprehensive determination of current traffic information including a road condition. The data of the sensors need only be evaluated by means of complex and complex computing processes either locally in the respective measuring points or centrally in a traffic control center. Therefore, this solution is also - in particular for a nationwide monitoring of a traffic area - associated with high infrastructural effort for installation of measuring points and the evaluation of the measured data.

Furthermore, it is also known to record so-called "floating car data" as traffic data, which is based, for example, on an exchange of information between in flowing traffic with moving vehicles and a traffic control center. The data is generated from a vehicle, which participates in the current traffic situation. The data may include both a state of driving and status data of a place when standing (eg in a traffic jam, at a traffic light system, etc.). In this case, a data record contains at least one time stamp as well as current location coordinates of the vehicle, which itself becomes the measuring point or measuring sensor when the floating car data method is used. The participating vehicle includes facilities for the continuous determination of its position, speed, etc., as well as for the transmission of this data to the traffic control center. Traffic information systems based on this approach are eg from the writings EP 1 209 647 A1 and US 2003/0009277 A1 known. However, this approach requires comprehensive equipment of vehicles with positioning modules as well as a sufficient number of vehicles in the traffic area to be monitored in order to obtain high-quality and nationwide traffic information. Furthermore, with this traffic information approach, data and information about a road condition must additionally be determined, for example, via other measuring units (eg weather stations, etc.) or direct demand from the respective users of the vehicles. In addition, the Floating Car Data relatively high communication costs caused by frequent data transmission to the traffic control center.

It is also known to determine movement data from radio signals from mobile devices in a cellular radio network and to process them to traffic information. Such methods are for example in the writings EP 1 437 013 B1 and DE 10 2009 031 321 A1 disclosed. In this case, a radio network covering the traffic area to be monitored is used and movement data, in particular a speed, of the vehicles is determined from radio signals of the mobile devices carried in vehicles. However, such methods have the disadvantage that movement data of vehicles can only be obtained in certain sections. additionally For example, enough vehicles to collect the movement data must be available or registered in order to obtain high-quality, nationwide traffic information. In addition, even in the case of traffic information determined on the basis of a cellular radio network, a road condition must be queried via other measuring units (eg weather station, etc.) or by direct request from the respective users of the vehicles.

Presentation of the invention

The invention is therefore based on the object of specifying a method for determining traffic information, by means of which comprehensive current traffic information and a current road condition are determined in a simple and cost-effective manner.

The solution of this object is achieved by a method of the type described above, in which of each measuring unit over a measurement period vehicle noise -. the auditory environment of the respective measuring unit - is detected. These recorded vehicle noises, in particular rolling, driving and / or motor noises of vehicles, are then analyzed and evaluated on the basis of this analysis of the vehicle noise parameters for a traffic flow or for a traffic density and / or a weather-related condition of a Lane derived from the monitored traffic area.

The main aspect of the method according to the invention is that at each measuring point of the traffic area to be monitored by a measuring unit the auditory environment - ie rolling, driving or engine noise - this measuring point, for example cyclically or during a certain measurement period are recorded. By evaluating the vehicle noise over the measurement period on the basis of comparative data, a speed of the vehicles - passenger cars and trucks - can then be estimated and from this an information derived via traffic flow and / or traffic density. On the basis of the comparative data (eg rolling or driving noise on a dry road), it is also possible to make statements about the weather-related condition of carriageways. By means of the method according to the invention, it is possible to monitor a traffic area comprehensively without great expense, since measuring points or measuring devices can be used to use an already existing infrastructure of a road operator. In particular, the method according to the invention also makes it possible to determine information about the effect of the respective weather on the traffic across the entire area. Traffic problems (eg traffic jams, etc.) can also be located very easily.

Ideally, the analysis of the recorded vehicle noise is carried out above all with reference to the frequency spectrum, energy per frequency and / or change in the vehicle noise over the measurement period. The frequency spectrum indicates a composition of a sound or signal from its frequency-dependent noise or signal components. Based on the comparison data, individual vehicles are detected in the detected vehicle noises and made therefrom e.g. derives a vehicle speed by means of Doppler effect. In addition, a number of passenger cars and / or trucks can be interpolated from an energy density per frequency or per comparison spectrum and thus very easily be deduced to a current traffic density. From a change in the vehicle noise compared to the comparison data, for example, a weather-related condition of the road can be derived very easily.

Comparative data is used as the basis for an analysis of the recorded vehicle noise. It is advantageous if used for the analysis as comparison data obtained by audio and / or video analysis frequency pattern of rolling, driving and / or engine noise of vehicles and vehicle noise changes in dependence on a respective state of the roadway of the monitoring traffic area become. In the comparison data, for example, frequency patterns of vehicle noises of different vehicles (eg, cars, trucks, etc.) are assigned, which have been generated by means of a combined audio and / or video analysis. This vehicle noise and eg their frequency spectra of certain types of vehicles are known and can be very easily detected in the analysis and evaluation of the detected vehicle noise and used for the determination of traffic information.

Furthermore, further comparison data can be determined by changing vehicle noise changes in known weather conditions, e.g. in case of moisture, rain, ice, snow, etc. are derived from vehicle noise on dry roads. By means of these comparative data, a weather-related condition of a roadway in the monitored traffic area can then be determined very simply by the analysis.

In an expedient development of the method according to the invention, each measuring unit is connected to a computing unit and a comparison database. The driving noise is detected by a measuring unit in the measuring point and can then be forwarded for example via an interface unit to a computing unit. A comparison database is linked to the arithmetic unit, in which the comparison data for the analysis are stored. The arithmetic unit then uses the comparison data stored in the comparison database to analyze and evaluate the detected vehicle noises.

The results of the analysis may then be conveniently forwarded to a central processing unit for cumulation. In the central unit, the results of the respective measuring units or measuring points can then be compared with results of adjacent measuring units or measuring points. In this way, an improvement of the data quality can be achieved very easily by accumulation and / or averaging. Especially in traffic areas such as For example, highways, highways, etc. is usually the same traffic in road sections between exits, so that the data quality can be improved. Deviations are detected in particular in case of disturbances in the flow of traffic, eg due to construction sites, accidents, etc. or changes in weather conditions (eg local rain, snow or icing). Thus, a nationwide and high quality traffic information can be determined very easily.

A connection of the measuring units to the arithmetic unit and the comparison database can be done locally, for example. This means that each measuring point has an arithmetic unit and a comparison database to which the measuring unit is connected, for example. connected via an analog / digital converter as an interface unit. The calculations for an analysis and evaluation of the detected vehicle noise can be carried out locally in the respective measuring point and the results for later evaluation, for example, stored locally and / or sent for cumulation to the central unit. Since in this decentralized embodiment of the method according to the invention only the results of the analysis are transmitted to the central unit, only a small bandwidth in the transmission network (for example radio network, data network, etc.) is necessary for this. However, it may ideally be the entire frequency space occupied by the measuring unit and by e.g. covered analog / digital converter is used for detecting vehicle noise.

Alternatively, the inventive method can also be configured centrally. This means that both the arithmetic unit and the comparison database are located on a central server. From this server then appropriate connections are established, for example via a telecommunications network to the respective measuring points and thus to the measuring units. The driving noises are forwarded by the measuring units to the arithmetic unit and centrally evaluated. The central server can then display the results of the measuring points or Forward measurement units to the central unit for cumulation. This central variant of the method according to the invention has the advantage that not every measuring point has to have a computing unit and a comparison database.

However, the central variant has a limitation in detecting the vehicle noise and the frequency range compared to the decentralized variant. By transmitting the detected vehicle noise from the measuring units via a telecommunications network, in particular voice network, due to the available bandwidth in this network with existing number of measuring points or measuring units, the vehicle noise from different measuring points can be recorded only sequentially. By contrast, the decentralized variant can be continuously measured. In addition, in the central variant of the method of the frequency range is limited by the transmission network or telecommunications network used - for example, 300Hz to 3400Hz in voice telephony and 300Hz to 7000Hz in broadband telephony.

It is advantageous if emergency call devices are used as measuring points along the traffic area to be monitored. The measuring units can be integrated into these emergency call systems. Ideally, existing sound transducers, in particular microphones, can also be used as measuring units in the measuring points or in the emergency call devices. This can be used very easily existing infrastructure of a road operator for a determination of traffic information and a comprehensive traffic monitoring can be achieved. In addition, the use of emergency facilities or the existing sound transducer has the advantage that in a decentralized embodiment of the method - with the exception of emergency calls - a continuous measurement of vehicle noise is possible, the entire covered by sound transducer frequency range (eg 20Hz to 16000Hz) can be used.

Brief description of the drawing

The invention is explained schematically below by way of example with reference to the accompanying figures.

FIG. 1 shows schematically and by way of example a sequence of the method according to the invention for determining traffic information.

In FIG. 2 is an example and schematically illustrated a flow of the method according to the invention for the determination of traffic information in a decentralized embodiment of an analysis step.

FIG. 3 shows by way of example and schematically a sequence of the method according to the invention for the determination of traffic information in the case of a central configuration of an analysis step.

Embodiment of the invention

FIG. 1 schematically shows an exemplary sequence of the method according to the invention for the determination of traffic information. It is in FIG. 1 an example to be monitored traffic area VB such as a directional lane of a highway or expressway shown on which vehicle move in a direction FR. The traffic area VB to be monitored has a fault S at one point.

Measuring points MP1, MP2, MP3 are arranged along the traffic area VB to be monitored. As measuring points MP1, MP2, MP3, for example, emergency call devices are used along the traffic area VB. The measuring points MP1, MP2, MP3 are each provided with associated measuring units ME1, ME2, ME3. As measurement units ME1, ME2, ME3 can be integrated, for example, in the measuring points MP1, MP2, MP3 or emergency call devices or existing transducers or microphones are used.

In a first method step 1, at the respective measuring points MP1, MP2, MP3 of the respective measuring units ME1, ME2, ME3, vehicle noises FG - i. an auditive environment of the respective measuring point MP1, MP2, MP3 - detected cyclically or during a certain measurement period. The vehicle noise may be composed, for example, of rolling, driving and engine noise of vehicles. Due to the disturbance S, the different measuring points MP1, MP2, MP3 have a different auditory environment. At a first measuring point MP1 the vehicles are e.g. with appropriate travel speed in motion. At a second measuring point MP2, due to the disturbance S, e.g. stationary or slowly rolling traffic. A third measuring point MP3 is e.g. because of the preceding disorder S of no or very few vehicles happened. Thus, the measuring points MP1, MP2, MP3 a different auditory environment and it will be detected by the measuring units ME1, ME2, ME3 different vehicle noise FG.

In a second method step 2, the detected vehicle noises of the respective measuring unit ME1, ME2, ME3 are analyzed and evaluated on the basis of comparative data. Depending on the configuration, this second method step 2 can be carried out locally in the respective measuring points MP1, MP2, MP3 - as exemplified in FIG FIG. 2 represented - or centrally - as exemplified in FIG. 3 shown - done. On the basis of the analysis and evaluation of the recorded vehicle noise FG, parameters or information for a traffic flow, a traffic density, etc. as well as for weather-related condition of a roadway of the traffic area VB to be monitored are then derived for the respective measuring points MP1, MP2, MP3.

As a basis for the analysis and evaluation of the vehicle noise FG in the second method step 2, for example, frequency patterns of rolling, driving and engine noise are different Vehicles (eg cars, trucks, etc.), which are obtained by a combined audio / video analysis used. As further comparative data, for example in the case of known weather conditions, vehicle noise changes in the event of moisture, rain, ice slipperiness, open or closed snow cover, etc., can be derived from vehicle noise FG on a dry road.

Based on these comparison data stored in a database, then e.g. Individual vehicles are detected in the detected vehicle noise FG and determined by means of Doppler effect a vehicle speed as a parameter for traffic information or a traffic flow. Furthermore, further parameters (for example number of vehicles, etc.) can be obtained from an energy density per comparison spectrum or per frequency. For information about traffic flow and / or traffic density, the detected vehicle sounds FG are detected e.g. in terms of frequency spectrum and energy per frequency analyzed using the comparative data. From an evaluation, in particular of rolling noises, by means of the comparative data, e.g. be closed to a state of the roadway of the monitored traffic area VB with respect to dry roads, wet roads, rain, ice or snow.

In a third method step 3, an analysis and evaluation result of each measuring point MP1, MP2, MP3 is then forwarded via a communication network NW to a central unit ZE. In this central unit ZE, for example, a topology database DB may be appropriate, in which a topology of the monitored traffic area VB such as number and position of the measuring points MP1, MP2, MP3, structure, history of the traffic area VB, etc. are stored. The central unit ZE represents a cumulation level in which in a fourth method step 4 the results of the measurement points MP1, MP2, MP3 and above all the results of adjacent measurement points MP1, MP2, MP3 are adjusted.

As a rule, the traffic or a number of vehicles, e.g. in a traffic area with no entrances and exits between these entrances and exits, the same - i. e. From all measuring points MP1, MP2, MP3, nearly the same or very similar results are provided. As a result, by accumulating and / or averaging the results in the central unit ZE an improvement in the quality of the traffic information obtained from the vehicle noise can be obtained.

Deviations in the results of the measuring points MP1, MP2, MP3 result in disturbances S of the traffic flow, e.g. due to construction sites, accidents, etc. or due to a change in weather conditions such as local rain shower, snow or icing border, etc. By matching the results of the measuring points MP1, MP2, MP3 on the cumulation level in the fourth method step 4 then such interference S, which can be derived from the results of the respective measuring point MP1, MP2, MP3, very easy to locate.

Thus, e.g. the disturbance S is detected by the analysis of the vehicle noises picked up at the second measuring point MP2 (the analysis shows that, for example, at the second measuring point MP2 the vehicles are standing or moving very slowly). By matching with the adjacent measurement points MP1, MP3, the disturbance can also be located and displayed, for example, in a fifth method step 5 via an output unit (e.g., screen, electronic card, etc.). However, it is also conceivable for the information about the interference S to be forwarded by the central unit ZE via the communication network NW (for example radio network, etc.) to output units AE of the road users (for example navigation units and / or services) and then displayed.

As already stated, the method according to the invention, in particular the second method step 2 - ie the analysis and evaluation of the detected vehicle noise FG - be configured locally or decentralized. FIG. 2 shows schematically and by way of example a sequence of the method according to the invention with a decentralized embodiment of the analysis or evaluation of the vehicle noises.

In FIG. 2 an exemplary measuring point MP4 is shown, which is mounted along a traffic area VB to be monitored. This measuring point MP4 comprises a measuring unit ME4. As a measuring point MP4 an emergency call device and as a measuring unit ME4 of integrated in the emergency call device sound transducer can be used. Furthermore, a computing unit RE1 and a comparison database V1 are accommodated in the measurement point MP4, in which the comparison data for the analysis and evaluation are stored. The measuring unit ME4 is connected via an interface unit AD such as an analog / digital converter AD to the arithmetic unit RE1 and the comparison database V1.

In the first method step 1, the vehicle noise FG in the environment of the measuring point MP4 is detected by the measuring unit ME4. These vehicle noises FG are forwarded in the second method step 2 to the arithmetic unit RE1 and analyzed and evaluated by the latter with the aid of the comparison data from the comparison database V1. Then, the results of the analysis can be stored for later further evaluation or sent in the third method step 3 via a communication network NW to the central unit ZE. Since only the results of the analysis are transmitted, only a small bandwidth in the communication network NW is necessary. For a detection of the vehicle noise by the measuring unit ME1 is thus an entire frequency space available, which are covered by the measuring unit ME1 and the interface unit AD. When using an emergency call device as the measuring point MP4 and the sound transducer or microphone available therein as the measuring unit ME4, this is, for example, a frequency range from 20 Hz to 16000 Hz. In addition, it can - with the exception of emergency calls - continuously vehicle noise can be detected by the measuring unit ME4.

In the fourth method step 4, the results of the measuring point MP4 are then adjusted or cumulated by the central unit ZE with results of adjacent measuring points. The central unit ZE can again be provided with a topology database DB, in which a topology of the traffic area VB to be monitored is stored. In the fifth method step 5, accumulation results such as e.g. determined disturbances in traffic or determined weather-related road conditions of an output unit AE made available for display.

Alternatively, the analysis and evaluation of the detected vehicle noise FG, however, also - as exemplified in FIG. 3 presented - centrally done. FIG. 3 shows by way of example and schematically a measuring point MP5, which is mounted along a traffic area to be monitored VB. This measuring point MP5 - for example an emergency call device - again comprises a measuring unit ME5 (eg a sound transducer or a microphone) as well as an interface unit IF1. A computing unit RE2 and an associated comparison database V2 are centrally located on a server. A connection can be set up between the measuring point MP5 and the arithmetic unit RE2 via a first communication network NW1 and a second interface unit IF2 (eg a telephone interface) in order to transmit detected vehicle noises FG to the arithmetic unit RE2.

In the first method step 1, the vehicle noise FG of the environment of the measuring point MP5 is detected by the measuring unit ME5. In the second method step 2, a connection is first established via the first communication network NW1 to the computing unit RE2 - for example in the form of a telephone connection. As the first communication network NW1 can be provided, for example, an analog, an IP or ISDN telephone system. The detected vehicle noises FG are then from the measuring point MP5 transmitted to the computing unit RE2 and analyzed and evaluated by this with the aid of the comparison data stored in the comparison database V2. The computing unit RE2 can thus centrally analyze and evaluate the vehicle noise FG detected by a plurality of measurement points MP5.

According to the bandwidth available in the first communication network NW1, however, only a sequential recording of vehicle noises from the different measuring points MP5 is possible with an existing number of measuring points MP5. Furthermore, a central analysis results in a restriction of the frequency range by the first communication network NW1 used. For example, when using a telephone system, the frequency range is limited to 300Hz to 3400Hz, when using a broadband telephone system to a frequency range of 300Hz to 7000Hz.

After the analysis and evaluation of the vehicle noise FG by the arithmetic unit RE2 in the second method step 2, the results of the analysis of the individual measuring points MP5 in the third method step 3 via a second communication network NW2 again to a central unit ZE for cumulation or adjustment of adjacent measuring points MP5 forwarded. In the fourth method step 4, the results in the central unit ZE can then be adjusted accordingly and disturbances, e.g. be localized using the topology database DB. In the fifth method step 5, accumulation results such as e.g. determined disturbances in traffic or determined weather-related road conditions of an output unit AE made available for display.

Claims (8)

Method for determining traffic information, wherein measuring points (MP1, MP2, MP3) are arranged on the road side along a traffic area (VB) to be monitored and measuring units (ME1, ME2, ME3) are provided for these measuring points (MP1, MP2, MP3), characterized in that from each measuring unit (ME1, ME2, ME3) over a measuring period vehicle noise (FG) are detected (1), that then based on comparative data, the recorded vehicle noise (FG) are analyzed and evaluated (2), and then based on an analysis of the detected vehicle noise (FG) parameters for a traffic flow and / or a weather-related condition of a roadway of the monitored traffic area (VB) are derived (2, 4). A method according to claim 1, characterized in that the analysis of the detected vehicle noise (FG) in particular with respect to frequency spectrum, energy per frequency and / or change of the vehicle noise (FG) over the measurement period is performed (2). Method according to one of claims 1 to 2, characterized in that as comparison data obtained by audio and / or video analysis frequency pattern of rolling, driving and / or engine noise of vehicles are used (2). Method according to one of Claims 1 to 3, characterized in that vehicle noise changes as a function of a respective state of the roadway of the monitoring traffic area are used as comparison data (2). Method according to one of claims 1 to 4, characterized in that each measuring unit (ME1, ME2, ME3) is connected to a computing unit (RE1, RE2) and a comparison database (V1, V2). Method according to one of claims 1 to 5, characterized in that results of the analysis for cumulation to a central processing unit (ZE) are forwarded (3), and that thereby results of adjacent measuring units (ME1, ME2, ME3) are compared (4). Method according to one of claims 1 to 6, characterized in that are used as measuring points (MP1, MP2, MP3) along the monitored traffic area (VB) emergency call devices in which the measuring units (ME1, ME2, ME3) are integrated. Method according to one of claims 1 to 7, characterized in that as measuring units (ME1, ME2, ME3) in the measuring points (MP1, MP2, MP3) existing sound transducer, in particular microphones, are used.

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