DE102015119392A1 - Method and device for comparison-controlled derailment detection - Google Patents

Method and device for comparison-controlled derailment detection Download PDF

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Publication number
DE102015119392A1
DE102015119392A1 DE102015119392.2A DE102015119392A DE102015119392A1 DE 102015119392 A1 DE102015119392 A1 DE 102015119392A1 DE 102015119392 A DE102015119392 A DE 102015119392A DE 102015119392 A1 DE102015119392 A1 DE 102015119392A1
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Germany
Prior art keywords
measurement data
bogies
wheelsets
contraption
rail vehicle
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Pending
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DE102015119392.2A
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German (de)
Inventor
Andrea Etzbach
Ulf Friesen
Frank Günther
Marc-Oliver Herden
Reinhold Mayer
Stefan Schneider
Stefan Sedlmair
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Knorr Bremse Systeme fuer Schienenfahrzeuge GmbH
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Knorr Bremse Systeme fuer Schienenfahrzeuge GmbH
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Priority to DE102015119392.2A priority Critical patent/DE102015119392A1/en
Publication of DE102015119392A1 publication Critical patent/DE102015119392A1/en
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B61RAILWAYS
    • B61FRAIL VEHICLE SUSPENSIONS, e.g. UNDERFRAMES, BOGIES OR ARRANGEMENTS OF WHEEL AXLES; RAIL VEHICLES FOR USE ON TRACKS OF DIFFERENT WIDTH; PREVENTING DERAILING OF RAIL VEHICLES; WHEEL GUARDS, OBSTRUCTION REMOVERS OR THE LIKE FOR RAIL VEHICLES
    • B61F9/00Rail vehicles characterised by means for preventing derailing, e.g. by use of guide wheels

Abstract

The invention relates to an apparatus and a method for detecting a derailment of a rail vehicle, wherein measurement data characterizing a driving operation of a plurality of wheelsets or bogies (10-1 to 10-n) of the rail vehicle are collected and compared in a comparator (40), and wherein the presence of a derailment is determined when the measurement data of at least one wheelset or bogie differ by at least a predetermined extent from the measurement data of the remaining wheelsets or bogies.

Description

  • The present invention relates to an apparatus and method for detecting a derailment of a rail vehicle having a plurality of individual wheelsets or bogies. The invention also relates to a computer program with code means for carrying out the steps of the aforementioned method on a computer system, and a computer-readable storage medium on which a program code having the code means of the computer program is stored.
  • Without technical aids a derailment of a wheelset or a bogie of a rail vehicle from the train driver, especially on long trains, often can not be detected. The derailed wheel set then goes unnoticed and is dragged along, and the derailed car runs the risk of colliding with a tunnel, a bridge or an oncoming train. In order to minimize this risk, a derailment must be detected as early as possible, so that appropriate countermeasures such as an emergency braking can be initiated by the train driver or the brake control of the rail vehicle.
  • In practice, in addition to simple mechanical systems (crossbars that cause a message / action on contact with the rail or obstacles) and pneumatic detectors (spring-mass oscillator, which opens a valve at a certain vibration threshold and opens the main air line) are mainly used in freight wagons electronic systems for the detection of derailment.
  • In addition to methods for inductive determination of the track position systems are in use, the accelerations on the car, e.g. Measure at the axle box or bogie and process further. Since a derailed wheel set is subject to acceleration caused by the derailment, it is known to monitor the acceleration of the wheel set, preferably the vertical acceleration, directly on the wheel by means of an acceleration sensor. In particular, a derailed wheel set rolls or jumps over the superstructure of the busy traffic lane, whereby strong shocks and thus high accelerations are impressed into the wheel set. The acceleration signal output by the acceleration sensor can then be evaluated by an evaluation device in order to determine the state of the wheelset, derailed or not derailed. In principle, the acceleration of the bogie can be monitored, which is damped, however. For example. For the purpose of detection, acceleration signals are evaluated at the axle bearings of a wagon and a derailment is detected when a degressed wheel set moves over thresholds.
  • From the DE 199 53 677 C1 is a method is known in which the signal of the acceleration sensor is integrated twice and compared with an upper and a lower limit, which is detected when falling below or exceeding the respective limit on a derailment. The disadvantage of this, however, is that a derailment detection only at the actual derailment time is possible, but not afterwards.
  • It is also known to check the acceleration signal for a correlation with a threshold frequency. However, this presupposes the presence of sleepers in the track superstructure, in addition to the fact that the thresholds must have uniform distances and the speed of the rail vehicle must be within a certain range.
  • However, the currently used in practice systems for derailment detection are either limited in their application to a certain speed and / or require a certain superstructure of the track body, so that a derailment can be detected. For trains with speeds over 100 km / h and for routes with so-called "slab track" currently used in practice systems for derailment detection are limited or not usable. The disadvantage of this method is that it "only" the actual derailment process is detected. Should, for some reason, e.g. due to external influences such as track position, cornering, higher speeds, etc. the behavior is different than the expected acceleration course, the derailment is not recognized.
  • The invention has for its object to provide a detection mechanism that allows both in all speed ranges (especially at higher speeds) and regardless of the type of roadway (sleepers, fixed carriageway, ...) detection.
  • This object is solved by the features of the independent claims.
  • Furthermore, the invention relates to a computer-readable storage medium, on which a program code executable on a computer system is stored, which generates or implements the steps of the aforementioned method.
  • Furthermore, the invention relates to a computer program with code means which, when executed on a computer system, generate or implement the steps of the aforementioned method.
  • Thus, the detection of a derailment of a rail vehicle takes place in that measurement data characterizing the driving operation of a plurality of wheelsets ( 10-1 to 10-n ) or bogies of the rail vehicle are collected and compared, wherein a derailment is detected when the measurement data of at least one wheelset or bogie differ by at least a predetermined extent from the measurement data of the other wheelsets or bogies. The basic idea of the invention is therefore to differentiate at several measuring points on the train or bogie or the axes between the states "not derailed" and "derailed" by measuring data (eg measured vibration data, preferably vertical direction, alternative to vibration other data would be conceivable, eg optical data, for example, for distance measurement wheel-rail, or mechanical or electrical parameters) of multiple wheelsets or single wheels are compared. It is assumed that driving over the same location causes comparable vibrations in all non-derailed wheelsets, while the behavior of the wheel sets deviates significantly. This procedure is particularly advantageous if the derailed and not derailed state in the acceleration level differ only slightly and therefore only a relative or comparative-dependent evaluation provides reliable results
  • According to an advantageous development, the measured data can specify a distance between wheel and rail on the respective wheel set or bogie. Thus, by comparing the distances at the different measuring points can be concluded that a derailment, if at a measuring point, a significant deviation of the measured distance compared to the other measuring points is determined.
  • According to a further advantageous development, the measured data of a respective middle wheel set or a middle bogie can be compared with the measured data of a predetermined number (for example one or two) of wheelsets or bogies in front and behind them.
  • According to a further advantageous refinement, the received measurement data can be allocated for the comparison in accordance with a time offset with which the respective wheelsets or bogies pass over the same location on a rail. This can ensure that the measured data are compared with each other in a timely manner and that incorrect decisions are avoided.
  • According to a further advantageous development, the comparison of the collected measurement data can, for example, be carried out on a cross-correlation or a cross-correlation spectrum. By this comparison approach, a reliable evaluation based on the similarity of the collected measurement data at different measuring points can be achieved. In particular, the comparison can be made, for example, to determine whether the maximum of the cross-correlation shows a time offset, which results from the travel speed of the rail vehicle and the distance between the axles of the compared wheelsets or bogies.
  • According to yet another advantageous development, a post-processing of the collected measurement data can be carried out in order to increase the reliability of the comparison operation. The follow-up may include, for example, at least one of resampling, filtering, forming a moving average or standard deviation, and forming an average.
  • According to yet another advantageous development, the measurement data can also specify a wheel speed, this allowing a supplementary application of the derailment detection for deriving a wheel diameter for Raddurchmesserkompensation.
  • Further advantageous embodiments and modifications of the invention will become apparent from the dependent claims.
  • The invention will be explained in more detail by means of embodiments with reference to the accompanying drawing figures. Show it:
  • 1 a schematic block diagram of a system for derailment detection according to a first embodiment; and
  • 2 a flowchart of a method for derailing detection according to a second embodiment.
  • The following is a description of advantageous embodiments with reference to an exemplary rail vehicle with a number n of wheelsets with associated measuring points for obtaining measurement data characterizing the driving operation.
  • 1 shows a schematic block diagram of a system for detecting a derailment, wherein the vibrations during driving operation indicating measurement data on n wheelsets 10-1 to 10-n by means of appropriate detectors (D) 20-1 to 20-n be won. The measured data or measuring signals at the output of the detectors 20-1 to 20-n can then optionally post-processing in appropriate post-processing facilities (N) 30-1 to 30-n be nauseated. Such a follow-up of the measured For example, data prior to comparison may include at least one of resampling, filtering, moving RMS or standard deviation, and moving average. As a result, either the computing time or data transmission can be reduced or the reliability of the algorithm can be increased.
  • The measured vibration data (preferably in the vertical direction, as an alternative to vibrations would also be other data such as optical data for distance measurement wheel-rail conceivable) are at the multiple wheelsets or single wheels 10-1 to 10-n won and possibly followed up. This is followed by a comparison of the measured data in a comparison device (V) 40 , where, for example, the measurement data of each wheel 10-1 to 10-n be compared with the measured data of the front in the direction of travel of the rail vehicle and behind it. It is assumed that driving over the same place in all non-derailed wheelsets causes comparable vibrations (or other characteristics characterizing the driving operation), while the behavior of the wheelsets deviates significantly. If the comparator 40 by comparing the collected measurement data finds that along the rail vehicle at least one wheel set distinctive differences in the measured data has (ie, the measured data differ by at least a predetermined extent from the measurement data of the other wheelsets or bogies) is assumed by a derailment and a corresponding output signal 50 issued. In this case, the time offset can be considered, with the wheelsets 10-1 to 10-n Overrun the same location on the rail, so that the measured data are compared in real time.
  • The comparison in the comparator 40 can be done using a cross-correlation or a cross-power density spectrum between the measured vibration data (eg acceleration data or signals). In the cross-correlation, for example, it can be compared whether the maximum of the correlation shows up at a time offset which results from the known travel speed and the known distance of the compared axes.
  • An advantage of the proposed comparative derailment detection is that a reliable derailment detection is possible even in those cases in which the derailed and undigested state differ only slightly in the acceleration level. This is, for example, in a bad rail section of the case in which even in the non-derailed state high vibrations occur, or at a fixed lane, which causes even in the derailed state only low vibrations without characteristic frequency content.
  • 2 shows a flowchart of a derailment detection method according to a second embodiment, which can be implemented, for example, as software in a computerized derailment detection device.
  • After the program starts in step 201 first measurement data of a measured at different measuring points (eg on the wheelsets or bogies) along the rail vehicle, the driving characteristic characterizing parameters (eg vibration, acceleration, distance wheel-rail, etc.) collected while driving the rail vehicle. It follows in the step 202 an optional postprocessing of the data in the manner described above. Thereafter, the measurement data in step 203 subjected to a comparison, as explained, for example, in the first embodiment, and in the subsequent step 204 is continuously checked whether the measured parameter data at least one of the measuring points show a significant or significant difference, ie differ by at least a predetermined extent from the measurement data of the other wheelsets or bogies. As long as this is not the case, the procedure jumps back to the step 201 and new parameter data are read in by the detectors at the measuring points and collected. However, once in step 204 If a marked or significant difference is detected, the process proceeds to step 205 and derailment measures (ie signaling and / or countermeasures in case of derailment) are initiated.
  • The method according to the second embodiment can also be used together with other methods for derailment detection in order to increase their accuracy. Furthermore, the method can also be combined with a measurement of the wheel speed to derive the current wheel diameter and perform a compensation of the wheel diameter. Since the wheel diameter changes only slowly due to wear, wear and derailment can be distinguished from each other.
  • In summary, an apparatus and method for detecting derailment of a rail vehicle has been described, wherein measurement data characterizing a driving operation is collected and compared from a plurality of wheelsets or bogies of the rail vehicle, and the presence of a derailment is determined when the measurement data of at least one wheel set or bogie differ by at least a predetermined extent from the measurement data of the remaining wheelsets or bogies.
  • It is noted that in the embodiments described above, alternative or additional suitable, the driving operation characterizing optical, mechanical, electrical and / or acoustic parameters can be used for the comparison of the wheelsets or bogies.
  • The features of the invention disclosed in the foregoing description, in the drawings and in the claims may be essential to the realization of the invention both individually and in any combination.
  • QUOTES INCLUDE IN THE DESCRIPTION
  • This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.
  • Cited patent literature
    • DE 19953677 C1 [0005]

Claims (14)

  1. Contraption ( 40 ) for detecting a derailment of a rail vehicle, the device ( 40 ) is configured to receive measurement data of a plurality of wheelsets characterizing a driving operation ( 10-1 to 10-n ) or bogies of the rail vehicle, for comparing the measurement data of the plurality of wheelsets ( 10-1 to 10-n ) or bogies of the rail vehicle, and for detecting the presence of a derailment, if the measurement data of at least one wheelset or bogie differ by at least a predetermined extent from the measurement data of the remaining wheelsets or bogies.
  2. Contraption ( 40 ) according to claim 1, wherein the measured data indicate vibrations, in particular vibrations in the vertical direction, of the respective wheel set or bogie.
  3. Contraption ( 40 ) according to claim 1 or 2, wherein the measured data indicate a distance between the wheel and rail on the respective wheelset or bogie.
  4. Contraption ( 40 ) according to any one of the preceding claims, wherein the device ( 40 ) is configured to compare the measured data in each case a middle wheel set or a middle bogie with the measured data of a predetermined number before and behind wheelsets or bogies.
  5. Device according to one of the preceding claims, wherein the device ( 40 ) is configured to assign the received measurement data according to a time offset with which the respective sets of wheels or bogies the same place on a rail over run for comparison.
  6. Contraption ( 40 ) according to any one of the preceding claims, wherein the device ( 40 ) is configured to perform the comparison based on a cross-correlation or a cross-correlation spectrum.
  7. Contraption ( 40 ) according to claim 6, wherein the device ( 40 ) is designed to base the comparison on whether the maximum of the cross-correlation is exhibited at a time offset resulting from the travel speed of the rail vehicle and the distance of the axles of the compared wheelsets or bogies.
  8. Contraption ( 40 ) according to any one of the preceding claims, wherein the device ( 40 ) is configured to subject the measurement data before comparing a post-processing.
  9. Contraption ( 40 ) according to claim 8, wherein the post-processing comprises at least one of resampling, filtering, forming a moving average or standard deviation, and forming an average.
  10. Contraption ( 40 ) according to one of the preceding claims, wherein the measured data indicate a wheel speed and the device ( 40 ) is designed to derive a wheel diameter and to perform a Raddurchmesserkompensation.
  11. System for derailing a railway vehicle, comprising a device ( 40 ) according to one of claims 1 to 10 and a plurality of detectors ( 20-1 to 20-n ) for detecting the measurement data characterizing the driving operation of the plurality of wheelsets ( 10-1 to 10-n ) or bogies of the rail vehicle.
  12. Method for detecting a derailment of a rail vehicle, the method comprising: receiving measurement data of a plurality of wheelsets characterizing a driving operation ( 10-1 to 10-n ) or bogies of the rail vehicle, - comparing the measurement data of the plurality of wheelsets ( 10-1 to 10-n ) or bogies of the rail vehicle, and - detecting the presence of a derailment when the measurement data of at least one wheelset or bogie differ by at least a predetermined extent from the measurement data of the remaining wheelsets or bogies.
  13. A computer readable storage medium having stored thereon a program code executable on a computer system which, when executed, generates the steps of method claim 12.
  14. Computer program comprising code means which, when executed on a computer system, generate the steps of method claim 12.
DE102015119392.2A 2015-11-11 2015-11-11 Method and device for comparison-controlled derailment detection Pending DE102015119392A1 (en)

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DE102015119392.2A DE102015119392A1 (en) 2015-11-11 2015-11-11 Method and device for comparison-controlled derailment detection

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
DE102015119392.2A DE102015119392A1 (en) 2015-11-11 2015-11-11 Method and device for comparison-controlled derailment detection
EP16798665.2A EP3374246A1 (en) 2015-11-11 2016-11-10 Method and device for comparison-controlled detection of derailing
CN201680071143.9A CN108290585A (en) 2015-11-11 2016-11-10 For to compare the method and apparatus of control mode detection derailing
PCT/EP2016/077260 WO2017081146A1 (en) 2015-11-11 2016-11-10 Method and device for comparison-controlled detection of derailing
BR112018009450A BR112018009450A2 (en) 2015-11-11 2016-11-10 Comparative controlled derailment detection process and device

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CN (1) CN108290585A (en)
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WO (1) WO2017081146A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2019179720A1 (en) * 2018-03-23 2019-09-26 Siemens Mobility GmbH Measuring arrangement and method for detecting a derailment
CN110849288A (en) * 2019-11-29 2020-02-28 中车南京浦镇车辆有限公司 Rail vehicle derailment detection method based on vehicle body contour line

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CN109142524A (en) * 2018-08-14 2019-01-04 唐智科技湖南发展有限公司 A kind of track damage detecting method, device and equipment

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DE29811208U1 (en) * 1998-06-23 1998-10-01 Mayer Albrecht Dipl Ing Fh Wheel monitoring system for multi-axle vehicles
DE19827271A1 (en) * 1998-06-19 1999-12-23 Andreas Mueller Sensor supported ON LINE determination system with evaluation of wheel and track related data during train travel
WO2000002022A1 (en) * 1998-07-03 2000-01-13 Kuehn Robert Method and device for continuously monitoring any kind of element or unit for the appearance of changes
DE19953677C1 (en) 1999-11-09 2001-06-21 Deutsche Bahn Ag Rail vehicle derailment detection method, uses detection of acceleration of rail vehicle component in vertical or transverse direction relative to rail track
EP1236633A2 (en) * 2001-02-28 2002-09-04 Siemens SGP Verkehrstechnik GmbH Method for a general detection of derailment
DE102011001978A1 (en) * 2011-04-12 2012-10-18 Bombardier Transportation Gmbh Rail vehicle with derailment monitoring

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EP2253523A1 (en) * 2009-05-19 2010-11-24 Société des transports intercommunaux de Bruxelles Derailment detection device and method
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Publication number Priority date Publication date Assignee Title
DE19827271A1 (en) * 1998-06-19 1999-12-23 Andreas Mueller Sensor supported ON LINE determination system with evaluation of wheel and track related data during train travel
DE29811208U1 (en) * 1998-06-23 1998-10-01 Mayer Albrecht Dipl Ing Fh Wheel monitoring system for multi-axle vehicles
WO2000002022A1 (en) * 1998-07-03 2000-01-13 Kuehn Robert Method and device for continuously monitoring any kind of element or unit for the appearance of changes
DE19953677C1 (en) 1999-11-09 2001-06-21 Deutsche Bahn Ag Rail vehicle derailment detection method, uses detection of acceleration of rail vehicle component in vertical or transverse direction relative to rail track
EP1236633A2 (en) * 2001-02-28 2002-09-04 Siemens SGP Verkehrstechnik GmbH Method for a general detection of derailment
DE102011001978A1 (en) * 2011-04-12 2012-10-18 Bombardier Transportation Gmbh Rail vehicle with derailment monitoring

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2019179720A1 (en) * 2018-03-23 2019-09-26 Siemens Mobility GmbH Measuring arrangement and method for detecting a derailment
CN110849288A (en) * 2019-11-29 2020-02-28 中车南京浦镇车辆有限公司 Rail vehicle derailment detection method based on vehicle body contour line

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WO2017081146A1 (en) 2017-05-18
CN108290585A (en) 2018-07-17
EP3374246A1 (en) 2018-09-19

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