METHOD FOR DETECTING A RAIL VEHICLE DERAILMENT AND RAIL VEHICLE

Description

[0001] The invention relates to a method and a rail vehicle with a device for detecting a derailment of the rail vehicle.

[0002] To increase the operational safety of rail vehicles, it is desirable to detect a derailment as early as possible. Methods for derailment monitoring are already known. For example, DE 10 2011 001 978 A1 discloses a method for derailment monitoring of at least one wheel of a rail vehicle's bogie, in which a derailment signal representative of a wheel derailment is generated based on the result of a comparison of signals available in the rail vehicle.

[0003] WO 2015 / 100425 A1 discloses a method and a system for the continuous collection and analysis of operating parameters of a railway vehicle in order to detect abnormal operating conditions.

[0004] CN 105 480 249 A discloses a derailment detection device based on bearing saddle positioning. The subsequently published DE 10 2020 213 436.7 discloses a method for detecting a derailed state of a rail vehicle, comprising limiting a drive torque and detecting the derailed state if the vehicle speed is less than a speed threshold.

[0005] DE 10 2017 208 760 A1 discloses a method for detecting a derailment of a railway vehicle and a railway vehicle equipped for carrying out this method.

[0006] US 2021 / 107546 A1 discloses a system for preventing train derailments.

[0007] DE 10 2012 202 838 A1 discloses a joint with which two rail vehicles or two rail vehicle parts can be connected to each other and which has a rail vehicle (part) assembly.

[0008] The technical problem therefore arises of creating an alternative method for detecting a derailment and a corresponding rail vehicle that enables reliable and early detection of the derailment, especially at low vehicle speeds.

[0009] The solution to the technical problem is provided by the articles with the features of the independent claims. Further advantageous embodiments of the invention are described in the dependent claims.

[0010] A method is proposed for detecting the derailment of a rail vehicle, in other words, for detecting a derailed state of the rail vehicle. The rail vehicle can be, in particular, a streetcar or light rail vehicle, e.g., a tram. Of course, the rail vehicle can also be designed in a different configuration. The rail vehicle can be an assisted, semi-automated, highly automated, fully automated, or autonomous rail vehicle. It is possible that the rail vehicle is designed as an articulated vehicle, in which the car bodies cannot be separated from each other in a normal operating state and passage between the car bodies is possible while the vehicle is in motion. However, it is also possible that the car bodies can be separated from each other and / or passage between the car bodies is not possible while the vehicle is in motion.

[0011] The rail vehicle comprises or has at least two car bodies, these car bodies being connected to each other via a joint, in particular a pivot joint. The joint is arranged and / or designed such that it allows a rotational movement of the car bodies relative to each other when negotiating a curve, in particular about an axis of rotation that may be oriented parallel to a vertical axis (yaw axis) of the rail vehicle. However, it is alternatively or cumulatively possible that the joint allows a rotational movement about an axis of rotation that is oriented parallel to a pivot axis of the rail vehicle and / or a rotational movement about an axis of rotation that is oriented parallel to a pitch axis of the rail vehicle. Thus, it is possible that the pivot joint is designed as a so-called pivot-pitch-roll joint.

[0012] When negotiating a curve, the longitudinal axes of the car bodies can be angled relative to each other. The angle between these longitudinal axes can be defined, in particular, as an angle in a plane oriented perpendicular to a vehicle or car body vertical axis. The angle between the longitudinal axes can be determined, in particular, as the smaller of the two angles of intersection between the two longitudinal axes, where the sum of the smaller and the larger angles of intersection equals 180°. Therefore, the angle can be 0° when the rail vehicle (and thus also the car bodies) is traveling in an ideal straight line.

[0013] In the inventive method, a recognition device is used Angle information about the instantaneous angle between the car bodies is received. This angle information can be determined, for example, by a detection device, which may include an angle sensor. Of course, it is also conceivable that the angle information is determined from information about the instantaneous orientations of the car bodies, particularly their longitudinal axes. In this case, the detection device can include at least one device for detecting these orientations. The detection device can be connected to the recognition device via a data and / or signal link. Naturally, other methods of acquiring the angle information are also conceivable. Position information about the instantaneous position of the rail vehicle in a rail network is received. The position is determined in a reference coordinate system, for example, a global coordinate system.Position information can be determined, for example, by a positioning device, such as a GNSS-based device, an odometer-based device, and / or an infrastructure-based device. A GNSS-based device might, for example, include a GPS sensor. An odometer-based device might, for example, evaluate the distance traveled by the rail vehicle to determine its position. Such a device might, for example, detect the rotational speed of a wheel or wheelset of the rail vehicle and then, based on that rotational speed, determine a distance traveled and then the current position of the rail vehicle. An infrastructure-based device might, for example, beacon or balise detection device and / or a device for detecting the position of beacons or balises.The system includes signals generated by balises, whereby a position can then be determined based on the signals generated by this device. Of course, other methods for position determination can also be used and / or the position information determined by different methods can be fused to determine the position. Preferably, the accuracy of the position determination is greater than that of a purely GNSS-based position determination. The position information can also be used for the assisted, automated, or autonomous operation of the rail vehicle. The position determination device can also be connected to the detection device via a signal and / or data link. The current angle is compared with an angle expected for the current position.By comparing the current angle, a deviation between it and the expected angle, also known as the position-specific expected angle, can be determined. This deviation can be expressed, for example, as a signed difference. Alternatively, it can be expressed as the unsigned absolute value of the difference. A position can be assigned an expected angle, for example, through a predefined assignment. Thus, a predetermined assignment of expected angles to different vehicle positions or vehicle position ranges can exist, which is evaluated to determine the expected angle, for example, by the detection system.The values ​​for vehicle position and expected angle, as well as their relationship to each other, can be stored in a memory device within the rail vehicle or in an external memory device, such as a server. The memory device can be connected to the detection device via a wired or wireless signal and / or data connection. Alternatively, a functional relationship, a characteristic curve-based relationship, or another type of relationship between position and expected angle can exist and be evaluated for position-dependent or position-specific determination of the expected angle. In other words, the expected angle can be determined in a position-dependent manner.If the current angle deviates from the expected angle, an output signal is issued indicating a derailment of the rail vehicle. Alternatively, the output signal can be stopped, with the absence of an output signal indicating a derailment. In other words, the detection device can generate an output signal representing a derailment, i.e., the derailed state, if the deviation is greater than a predetermined value. The predetermined value can be 0° or a non-zero angle, for example, an angle greater than 1° or 5°. Of course, other angle values ​​can be selected depending on the application.

[0014] The detection device is configured as a computing unit or includes one. The computing unit, in turn, may be configured as a microcontroller or integrated circuit, or include one or more such components. The detection device may, in particular, provide the function of an evaluation unit.

[0015] In other words, a derailment is detected if the current angle deviates from an expected angle by more than a predetermined amount, particularly if it is larger or smaller than that angle. The output signal can be called a derailment signal. This derailment signal can be transmitted to a higher-level system. The higher-level system can then implement appropriate safety measures, such as braking the rail vehicle or warning other rail vehicles. The method advantageously enables reliable and early detection of a derailment, especially at low speeds. Furthermore, the proposed detection method is particularly suitable for rail vehicles operating autonomously, with driver assistance, or in automated mode.

[0016] In another embodiment, the angle and position information are received continuously. This can mean that the information is received continuously. Such continuous reception can mean receiving information at a predetermined frequency, which can be greater than 1 Hz. Furthermore, the current angle is continuously compared with the angle expected for the current position, and—as explained above—if the current angle deviates from the expected angle, an output signal is issued or the output signal is terminated. Thus, operational safety can be advantageously increased further, since derailments can be detected continuously and not just at specific times.

[0017] However, it is also possible that the information and the angle comparison are received in response to an event, i.e., when a predetermined event occurs, for example, when reaching a predetermined position, when being in a predetermined position range, when reaching a predetermined speed and / or another event.

[0018] In another embodiment, a derailment of the rail vehicle is only detected if the deviation of the current angle from the expected angle persists for a predetermined period. Thus, the output signal is only issued, or the output signal is only terminated, when a deviation persists for this predetermined period. This advantageously increases the reliability of the method. The predetermined period can be, for example, longer than 1 s, 5 s, or 10 s.

[0019] In another embodiment, the output signal is only output, or the output signal is only terminated, if the deviation exceeds or reaches a predefined threshold. This can also increase the reliability of the method, particularly since, for example, noise-induced false detection can be avoided or reduced.

[0020] In a further embodiment, to prepare the method for detecting a derailment of the rail vehicle, the expected angle of the car bodies relative to each other is determined for a multitude of positions in the rail network, and the corresponding information is stored. During operation of the rail vehicle, the stored information is then accessed to determine the expected angle. In other words, the previously described assignment is determined and stored in preparation so that it can subsequently be used to detect the derailment. The determination of the expected angle of the car bodies and their assignment to a position can be carried out by at least one test run, which can also be referred to as a calibration run.

[0021] For example, a test run of the rail vehicle can be conducted, and the angle between the car bodies can be determined for each position. Alternatively, it is also conceivable to determine the angle analytically, for instance, by calculating the expected angle based on prior information about the rail vehicle and track information. The analytical determination can thus depend on at least one vehicle characteristic, particularly a geometric property, and / or at least one environmental characteristic, particularly the curvature of the trajectory defined by the track. This can advantageously improve the reliability and accuracy of derailment detection.

[0022] According to the invention, the comparison of the instantaneous angle with the expected angle is only performed if the rail vehicle is located within a predetermined position range. The predetermined position range can, in particular, be the area encompassed by a depot. The predetermined position range can therefore only include predetermined vehicle positions. Specifically, a vehicle position can be assigned the information that it is a position within the predetermined position range. In the proposed method, it can be determined, prior to the comparison of the instantaneous angle with the expected angle, whether the vehicle position lies within the predetermined position range. Only if this is the case can the deviation be determined. Otherwise, the deviation is not determined.

[0023] The depot can encompass an area of ​​vehicle positions where vehicles are located for maintenance and storage. Since the permissible speed for rail vehicles, especially assisted, automated, or autonomously operated rail vehicles, is low in a depot, the method's suitability for derailment detection at low speeds results in particularly reliable and early detection.

[0024] A further proposal is for a rail vehicle with a derailment detection device. The rail vehicle has at least two car bodies connected by a hinge such that the longitudinal axes of the car bodies are angled relative to each other when the rail vehicle is traveling around a curve. The device includes a detection unit, either configured as a computing unit or as a computing unit configured to perform the derailment detection steps described above.

[0025] The device may further include a sensing device for acquiring angular information. The device may also include a position determination device. Furthermore, the device may include a communication interface for wireless and / or wired signal and / or data transmission, for example, to transmit the described output signal to a higher-level system and / or to receive angular and / or positional information from a higher-level system.

[0026] It is further possible that the device includes a storage device for storing position information, expected angles, and information about the mapping of expected angles to positions.

[0027] This advantageously results in a rail vehicle with improved operational safety, particularly at low speeds. The fact that the rail vehicle includes the device or the detection system does not preclude the possibility that a component of the device is external to the vehicle. However, it is conceivable that the device, or all components of the device, are permanently installed in the rail vehicle.

[0028] It is possible that the detection device is configured to continuously receive the angle information and the position information, to continuously compare the current angle with the angle expected for the current position, and to output a signal or to stop outputting a signal if the current angle deviates from the expected angle.

[0029] Furthermore, the rail vehicle may include a detection device. In this case, in particular, the detection device connected to the detection system may be configured to only determine that the rail vehicle has derailed if the deviation of the current angle from the expected angle persists for a predetermined period. This and the corresponding technical advantages have already been explained above.

[0030] Furthermore, the detection device can be configured to output the signal only, or to terminate the output signal only, when the deviation exceeds or reaches a predefined threshold. This and its corresponding advantages have already been explained previously.

[0031] Furthermore, the detection device can be connected to or have a data storage device in which information about the expected angle of the car bodies to each other is stored for a large number of positions in the rail network, and the detection device can be configured to access the stored information and determine the expected angle from it.

[0032] The invention is explained in more detail using exemplary embodiments. The figures show: Fig. 1 a schematic flowchart of a method according to the invention in a first embodiment, Fig. 2 a flowchart of a method according to the invention in a further embodiment, Fig. 3 a schematic block diagram of a device of a rail vehicle according to the invention and Fig. 4 a schematic representation of a rail vehicle.

[0033] In the following, identical reference symbols denote elements with the same or similar technical characteristics.

[0034] Fig. 1 shows a schematic flowchart of a method according to the invention for detecting a derailment of a rail vehicle 1 (see Fig. 4 ) according to a first embodiment. In a first step S1, angular information about an instantaneous angle MW between car bodies 2a, 2b of the rail vehicle 1 is received. This angular information can be received by a detection device 3 (see also Fig. 3 ) are received. It is possible that the angle information is received by a detection device 4 designed, for example, as an angle sensor (see Fig. 3 ) is detected / determined. In a second step S2, position information about the current position of the rail vehicle 1 in a rail network is received. This position information can also be received by the detection device 3. The position information can be determined with a position determination device 5. The in Fig. 1 The depicted sequence of the first and second steps S1, S2 is not necessarily fixed in the order shown. For example, the position information can be received before the angle information. However, the angle and position information should ideally be assigned to the same time, or to times that differ by no more than a predetermined amount. The time assigned to a piece of information refers specifically to the point in time at which the corresponding information is / was acquired.

[0035] In a third step S3, the instantaneous angle MW is compared with an expected angle EW for the instantaneous position. This expected angle EW can be a position-specific angle, determined, for example, by evaluating a previously known mapping between a position and expected angles EW. This mapping can be, in particular, in a storage device 6 (see Fig. 3 ) be stored.

[0036] In a fourth step, S4, the current angle MW is compared with the expected angle EW determined in this way. A deviation between these angles can be calculated for this comparison. If this deviation is greater than a predetermined threshold th, an output signal can be issued in output step AS, indicating a derailment of the rail vehicle 1 or representing a derailed state. Alternatively, the output of an output signal can be terminated in output step AS, so that the absence of the output signal indicates a derailment. If the deviation is less than or equal to the predetermined threshold th, no output signal indicating a derailment is issued, or the output of such a signal is not terminated. In this case, the procedure can be aborted or return to the first step, S1.

[0037] It is possible that the procedure is repeated, in particular continuously, especially if no deviation greater than the predetermined threshold th is detected in the fourth step S4.

[0038] It is also possible that after detecting that the deviation is greater than the predetermined threshold th, the sequence from the first to the fourth step S1-S4 is repeated one or more times, with the output step AS only being executed if the deviation persists for a period of a predetermined length, i.e., if it is detected in a plurality of directly consecutive repetitions of the sequence. The predetermined threshold th can be 0 or greater than 0.

[0039] Fig. 2 shows a schematic flowchart of a further embodiment of a method according to the invention. In this embodiment, the following correspond to the... Fig. 2 In the illustrated embodiment, the first step S1, the second step S2, the third step S3 and the fourth step S4 correspond to the respective steps of the in Fig. 1 embodiment shown. In contrast to the one in Fig. 1 In the illustrated embodiment, after the second step S2, an intermediate step ZS checks whether the current position corresponds to a predetermined position or lies within a predetermined position range. The position range can, for example, include the positions of rail vehicles in a depot. Only if the current position corresponds to the predetermined position or lies within the predetermined position range are the third and fourth steps S3 and S4 executed. If the current position does not correspond to the predetermined position or lies outside the predetermined position range, the subsequence of the third and fourth steps S3 and S4 is not executed. In this case, the process can be aborted or return to the first step S1.

[0040] Fig. 3 shows a schematic block diagram of a device 7 of a rail vehicle 1 according to the invention.

[0041] The device includes a detection unit 3 which is configured to detect the Fig. 1 oder Fig. 2 The described procedures are carried out. The detection device 3 can be connected via data and / or signal connections to a device for acquiring angular information about a momentary angle MW (see Fig. 4 The detection device 7 can be connected to the car bodies 2a and 2b of the rail vehicle 1. It can also be connected to a position determination device 5 and a data storage device 6. However, it is also possible that the device 7 includes, in addition to the detection device 3, the detection device 4, the position determination device 5, and / or the data storage device 6. Not shown is a communication interface of the detection device 3, through which an output signal can be issued indicating a derailment of the rail vehicle. Alternatively, the output of an output signal can be terminated, so that the absence of an output signal indicates a derailment.

[0042] Fig. 4 Figure 1 shows a schematic representation of a rail vehicle 1, which has a first car body 2a and a second car body 2b, which are connected to each other via a joint 8, such that the longitudinal axis 9a of the first car body 2a (in Fig. 4 (shown with dashed lines) and the longitudinal axis 9b of the second car body 2b (in Fig. 4 (shown as dotted lines) run at an angle to each other during a curve of the rail vehicle 1. In particular, the joint 8 enables a rotational movement of the car bodies 2a, 2b relative to each other about an axis of rotation that is oriented parallel to a vehicle vertical axis, which is perpendicular to the plane of the drawing. Furthermore, in Fig. 4 A momentary angle MW between the longitudinal axes 9a, 9b is shown. The rail vehicle 1 includes a detection device 3 which is configured to detect the in Fig. 1 oder Fig. 2The illustrated embodiments of the method for detecting a derailment of the rail vehicle 1 are to be carried out. It is further illustrated that the rail vehicle comprises a detection device 4 for acquiring angular information about the instantaneous angle MW. It is also illustrated that the rail vehicle 1 comprises a position determination device 5 and a data storage device 6.

[0043] The diagram shows that the first car body 2a could be the car body of a railcar. However, this is not mandatory. Reference symbol list

[0044] S1 first step S2 second step S3 third step S4 fourth step AS output step ZS intermediate step E expected angle MW current angle th threshold 1 rail vehicle 2a, 2b car body 3 detection device 4 acquisition device for acquiring angle information 5 position determination device 6 data storage device 7 device 8 joint 9a, 9b longitudinal axis

Claims

1. Method for detecting derailment of a rail vehicle (1) which has at least two car bodies (2a, 2b) connected to each other via a joint (8) so that the longitudinal axes (9a, 9b) of the car bodies (2a, 2b) are at an angle to each other during a curve of the rail vehicle (1), wherein - angle information about a current angle (MW) of the car bodies (2a, 2b) relative to each other is received, - position information about a current position of the rail vehicle (1) in a rail network is received, wherein the position is determined in a reference coordinate system, - the current angle (MW) is compared with an expected angle (EW) for the current position, and - in the event of a deviation of the current angle (MW) from the expected angle (EW), an output signal is output which indicates derailment of the rail vehicle (1), or the output of an output signal is terminated, so that the absence of the output signal indicates derailment of the rail vehicle (1), characterised in that the comparison of the current angle (MW) with the expected angle (EW) is only performed if the rail vehicle (1) is within a predetermined position range.

2. Method according to claim 1, wherein the angle information and the position information are received continuously, the current angle (MW) is continuously compared with the expected angle (EW) for the current position, and if the current angle (MW) deviates from the expected angle (EW), an output signal is output or the output of an output signal is terminated.

3. Method according to claim 2, wherein it is only determined that the rail vehicle (1) has derailed when the deviation of the current angle (MW) from the expected angle (EW) persists over a predetermined period of time.

4. Method according to any of the claims 1 to 3, wherein the output signal is only output or the output of the output signal is only terminated when the deviation exceeds or reaches a predetermined threshold value (th).

5. Method according to any of the claims 1 to 4, wherein, in preparation for the method for detecting derailment of the rail vehicle (1), the expected angle (EW) of the car bodies (2a, 2b) relative to each other is determined for a plurality of positions in the rail network and corresponding information is stored, and wherein later, during operation of the rail vehicle (1), the stored information is accessed and the expected angle (EW) is determined from it.

6. Rail vehicle with a device for detecting derailment of the rail vehicle (1), wherein the rail vehicle (1) has at least two car bodies (2a, 2b) which are connected to each other via a joint (8) so that the longitudinal axes (9a, 9b) of the car bodies (2a, 2b) are at an angle to each other during a curve of the rail vehicle (1), wherein the device comprises a detection device (3) which is designed as a computing device or comprises a computing device and is configured - to receive angle information about a current angle (MW) of the car bodies (2a, 2b) relative to each other, - to receive position information about a current position of the rail vehicle (1) in a rail network, wherein the position is determined in a reference coordinate system, - to compare the current angle (MW) with an expected angle (EW) for the current position, and - in the event of a deviation of the current angle (MW) from the expected angle (EW), to output an output signal indicating derailment of the rail vehicle (1), or to terminate the output of an output signal, so that the absence of the output signal indicates derailment of the rail vehicle (1), characterised in that the comparison of the current angle (MW) with the expected angle (EW) is only performed if the rail vehicle (1) is within a predetermined position range.

7. Rail vehicle according to claim 6, wherein the detection device (3) or a determination device connected to the detection device (3) is designed to only determine that the rail vehicle (1) has derailed when the deviation of the current angle (MW) from the expected angle (EW) persists over a predetermined period of time.

8. Rail vehicle according to any of the claims 6 to 7, wherein the detection device (3) is connected to or comprises a data memory device (6) in which information about the expected angle (EW) of the car bodies (2a, 2b) relative to each other is stored, and wherein the detection device (3) is designed to access the stored information and determine the expected angle (EW) from it.