METHOD FOR INFRASTRUCTURE-FREE DETECTION OF A RAIL VEHICLE CROSSING A TRACK SECTION

Description

[0001] The invention relates to a computer-based method for the infrastructure-free detection of a rail vehicle crossing a track section of a railway. The detection preferably takes place on-board, i.e. in the rail vehicle. According to the invention, the infrastructure-free detection is carried out using a track signature, which can be understood as a virtual beacon. A track signature is a location-dependent signal that is applied over a traveled path of a track network (see also DE-A-10 2012 219 111). A track network is divided into interconnected tracks. The signature of the virtual beacon is located on a section of track, called a track section, of a specific length. The different track sections for different virtual beacons are generally not connected but are separated by distances. Track signatures can be derived from measurements, e.g.the position and / or the attitude (in space) of the rail vehicle, the magnetic field, the vibrations acting on the rail vehicle (in one or more spatial directions), the track curvatures, the cornering (e.g. when turning at a switch), the "course angle" and / or the changes in the aforementioned parameters.

[0002] In particular, the invention relates to a supplement to a train localization method, such as ETCS (European Train Control System), with a virtual balise based on track signatures, in particular the magnetic field signature, the vibration signature, and the track curvature signature. A track signature is a location-dependent signal from measurement data acquired by the train, which is plotted over a traveled path.

[0003] Train localization determines, on the one hand, the track on which the rail vehicle is located, e.g., after passing a switch (or crossing), and, on the other hand, the longitudinal position on the track. The track identification number and the longitudinal position on the track form the localization result (track position).

[0004] Track accuracy or track selectivity means the correct determination of the correct track in switches or parallel track scenarios.

[0005] DE-A-10 2012 219 111 and DE-A-199 08 782 each describe a method for locating a rail vehicle within a rail network, in which at least one physical variable that changes depending on location and acts on the rail vehicle while it is traveling along the track, such as vibrations in the Z direction, i.e. vertical direction, the magnetic field, track curvatures and track superelevation, is determined. In this way, the signature of a track section is determined in the known method. The location- and / or time-dependent course of the at least one physical variable or its location- and / or time-dependence is compared with track signatures of the rail network that were previously determined by traveling along the rail network. This allows the rail vehicle to be located at any time and in any location on the rail network.

[0006] As already described above, it is known to use beacons to locate a rail vehicle (see, for example, EP-A-1 674 371). These are usually physical beacons (also called Eurobalises) that are activated when a rail vehicle passes over them and, in turn, transmit a code. This code is read by the rail vehicle and represents, for example, the track position, which can be used to calibrate a rail vehicle's own positioning system. The problem with physical beacons is that they must first be positioned in the rail network, which entails additional effort.

[0007] It is known from DE-A-10 2004 063 049 that a balise not only transmits predefined data, but can also send out modified data which, for example, provide information about special, for example temporary, conditions of a track section or a subsequent track section.

[0008] Various methods for determining the position of a rail-bound vehicle are described in DE-A-196 11 775 A1, DE-A-10 2010 033 372, DE-A-10 2015 205 535, and WO-A-01 / 66401. A speed indicator for a rail vehicle is known from DE-A-10 2010 024 800.

[0009] From DE-C-1 195 32 104 a method for determining the position of a vehicle moving on a given lane is known, in which objects arranged along the lane are detected.

[0010] In EP-A-3 069 955, the position of a rail vehicle within a rail network is detected by camera recording of the overhead line or contact wire.

[0011] The object of the invention is the detection of a crossing of a track section of a railway line by a rail vehicle, which does not require any special infrastructure for the recognition of the track signature.

[0012] To achieve this object, the invention proposes a method for detecting, without infrastructure, a crossing of a track section of a railway by a rail vehicle, wherein the method has the features of claim 1. Individual embodiments of the invention are the subject of the respective subclaims.

[0013] According to the invention, the real beacons required, for example, for the ETCS system are implemented virtually on the basis of track signatures determined by the local magnetic field. The track signature used according to the invention is therefore a magnetic field signature, either alone or in combination with a vibration signature, a track curvature signature and / or a track longitudinal inclination signature, which can be measured as a physical quantity in the rail vehicle when traveling over the railway. Wherever a virtual beacon according to the invention is to be positioned in the rail network, the track signature of the track section is determined in advance. The rail vehicle traveling along the railway continuously or quasi-continuously records the signature of the railway, i.e. the change or the course (location-dependent) of the physical quantity used for the track signature.The currently determined track signature is then compared with the previously created and stored track signatures. This allows the rail vehicle or a higher-level control center to determine which track section or beacon the rail vehicle is currently crossing or has just crossed.

[0014] In contrast to localization using track signatures, as described in DE-A-10 2004 063 049 and DE-A-10 2015 205 535, the invention detects the crossing of one of several selected track sections by comparing the track signature of the track section currently being crossed with the track signatures stored in the database for selected track sections. Unlike the known methods, the invention does not determine the probability that the train could be in a specific track section. Rather, a YES / NO decision is made, as is the case with real beacons. This is where the essential difference between the invention and the prior art regarding the use of track signatures can be seen.If the currently determined track signature matches one of the track signatures stored in the database, a signal is output that represents the location of the track section corresponding to the track signature. This lets a control center and / or the vehicle know where the vehicle is located or that it is on the "correct" track.

[0015] In a suitable embodiment of the invention, the data can include the track position (i.e., track identification number and track length parameters) and / or the geographical position of the detected track section and / or the local maximum speed and / or other data representing possibly changing conditions related to the travel and / or control of the rail vehicle. The other data transmitted by the virtual beacon, in addition to the track position and / or possibly the geographical position, can be the information described in detail, for example, in DE-A-10 2004 063 049.

[0016] According to the invention, the magnetic field, the vibrations, the degree of curvature and / or the position angle of the track section or a combination of the aforementioned quantities is used as the physical quantity describing a track signature.

[0017] In a further advantageous embodiment of the invention, the track sections for which track signatures are to be provided can be provided by means of physical changes in the respective track section. Such a physical change is suitable for the infrastructure-free detection according to the invention, since no real beacons, real landmarks, or similar additional infrastructure is required for detecting a track section crossing.

[0018] According to the invention, the comparison of currently determined track signatures with previously created track signatures of the rail network stored in a database is used to update virtual balises that change over time based on track signatures. Thus, if the track signature is determined when a rail vehicle to be located passes over a track section equipped with a virtual balise, and this track signature differs by more than a first deviation threshold and by less than a larger second deviation threshold from the stored track signature assigned to this track section, the current track signature is stored in a database as a new virtual balise for this track section, and from then on, this new, updated track signature is used as a virtual balise for subsequent rail vehicle localizations.

[0019] Alternatively, it is also possible to provide the virtual balise according to the invention with multiple track signatures in order to then check multiple measured track signatures for agreement with the track signatures of the balise. If, for example, the magnetic field track signature of the balise deviates from the currently measured magnetic field track signature, but there is a match with regard to other track signatures, it is detected that the rail vehicle is currently passing the virtual balise.

[0020] The concept of the inventive virtual balise using magnetic field track signatures can be viewed as a straightforward integration of additional measurements, such as vibration, acceleration, yaw rates, etc., into the ETCS. Current ETCS systems already have an interface for physical balises (radio beacons, Eurobalises), whereby balise measurements are used, among other things, for track location and longitudinal error correction. In addition to virtual balises using GNSS, the invention also allows virtual balises using signatures based on the same principle. A major advantage is their use in tunnels and underground.

[0021] According to the invention, the concept of the virtual beacon according to, for example, DE-A-10 2004 063 049 can be expanded by signature-based virtual beacons consisting of a signature (magnetic field with or without vibration and / or position and / or orientation and / or curvature) for the purpose of, for example, train localization. This is particularly advantageous in tunnels, subways, and train stations.

[0022] Real and virtual beacons are generally used to calibrate the on-board position determination. Starting from a detected beacon, the rail vehicle then determines its track position using on-board sensors, such as speed and / or acceleration, from which the distance traveled can then be determined. This determination is subject to drift. Therefore, the on-board position determination is updated again when the next beacon passes.

[0023] A virtual balise can not only transmit position information, but also other data associated with the detected track section and thus with the relevant track signature to the rail vehicle and / or a rail vehicle control center (control center, signal box, train driver).

[0024] According to the invention, the concept of the virtual balise is extended to include track signatures, namely the magnetic field signature and, if desired, additionally the vibration signature and / or the track curvature signature.

[0025] The structure of the inventive signature-based train localization with virtual balises with signatures is described in the Fig. 1 and 2 shown schematically in the drawing.

[0026] The signatures are generated from a measurement sequence from train-mounted sensors 3d and a sequence of speed values ​​3c, and then filtered. Using the speed, the temporally sampled measurement signal is transformed into the spatial domain. The method requires speed values ​​obtained from speed sensors (wheel rotation, Doppler radar) or from magnetic field or vibration measurements. A map or database 3b contains longitudinally parameterized reference signatures from transformed and filtered measurement data, which are stored together with a track identification number and the track length parameter (also track position). The localization result with the track identification number and the track position from signatures is achieved by comparing reference signatures from the map and the most recently measured measurement signature (block 3a).A detector 3e (YES / NO decision maker) decides whether and, if so, with which track signatures stored in the database 3b the currently measured track signature matches, and outputs a TRUE signal if a match with one of the stored track signatures is detected.

[0027] To locate a train using a virtual beacon according to the invention, the train is detected during its passage. The detected beacon has a known position in the track network, which is stored on the map. This provides the train location unit with a track position measurement. The virtual beacon signals are selected so that a virtual beacon is available for each route at suitable and discrete positions, at specific intervals, and especially after switches.

[0028] When the crossing of one of the track sections for which a track signature is stored in the database is detected, a signal or telegram 3g is sent to the balise interface of the train localization unit 8 (e.g. ECTS).

[0029] If necessary, permanently excited or electromagnetic magnets can be installed along the track for the inventive detection of a track section crossing using a magnetic field signature. These magnets can be individually positioned or arranged in a special arrangement with multiple magnets. This arrangement can also be implemented in a uniquely identifiable manner, e.g., with the lowest possible cross-correlation to other positions. Examples include gold codes.

[0030] Fig. 2shows the track areas in front of and behind a switch 7 (or cross switch). Rail vehicle 1 is located on track 2. Track 2 has a track section 2a with track signature 2b. Behind switch 7 are the two tracks 5 and 6, each with a track section 5a and 6a with track signatures 5b and 6b, respectively. The three track signatures 2b, 5b, and 6b are different, as shown by the characteristics of the magnetic field curve or other variables (e.g., additional vibration curve). List of reference symbols

[0031] Fig. 11Rail vehicle 2Track 2aTrack section 2bTrack signature of track section 2a 3Reference system with signature measurements 3aLocalization method of the reference system with signature 3bRoute map with signatures (database) 3cSpeed ​​information 3dMagnetic field sensor for signature measurement 3eDetector (YES / NO decision maker) 3gTelegram, signal to the balise interface 8Train localization system (e.g. ETCS) Fig. 2 4Track 4aTrack section 4bTrack signature of track section 4a 5Track 5aTrack section 5bTrack signature of track section 5a 7Switch

Claims

1. A method for detecting a crossing of a track section of a track of a railway of a rail network by a rail vehicle, wherein in said method - at least one track signature is provided in a database for each selected non-adjacent track sections of tracks of the railway, said track signature describing the course and / or the change of at least one location-dependent physical quantity acting on the rail vehicle when driving on the respective track section and thus characterizing the track section, - wherein the selection of track sections is based on distinguishable track signatures of track sections of the tracks of an area of the rail network, - the at least one physical quantity is detected and recorded by a sensor system of the rail vehicle when crossing the railway, - it is detected by comparing the recorded course of the at least one physical quantity and / or its change to the track signatures provided in the database whether the rail vehicle crosses or leaves one of the track sections for which there is a track signature in the database, and - a true signal is output if the recorded current course of the at least one physical quantity corresponds to one of the track signatures in the database or deviates therefrom by less than a predetermined maximum deviation threshold, - wherein the magnetic field alone or the magnetic field in combination with vibrations and / or with the degree of curvature and / or with the position angle of the track section are used as one of the physical quantities describing the track signature, characterized in that the speed of the rail vehicle in the track sections, for which a signature is provided, is measured, in that the track signatures provided for selected track sections are updated in the database based on the course of location and time of the at least one physical quantity currently determined when crossing a respective track section and / or the location- and / or time-dependent change of the at least one physical quantity, if the currently determined track signature differs from the track signature provided for the respective track section by more than a minimum deviation threshold that is smaller than the maximum deviation threshold.

2. The method according to claim 1, characterized in that a database stores, for each track section for which a track signature is provided, the track position with track identification number and longitudinal track parameters and / or the geographical position and / or the permissible maximum speed for the track section, and in that these data can thus be determined for a detected track section.

3. The method according to any one of claims 1 to 2, characterized in that the track sections for which track signatures are to be provided undergo physical changes.

4. The method according to any one of claims 1 to 3, characterized in that the permissible maximum speed in a track section is compared to the measured speed of the rail vehicle, and in that a warning, a message or a telegram is provided to the train driver and / or to the train protection electronics and / or to a control center when the permissible maximum speed is exceeded.