SENSOR ARRANGEMENT, APPARATUS FOR POSITION DETERMINATION, RAIL VEHICLE AND METHOD FOR POSITION DETERMINATION FOR A RAIL VEHICLE

Abstract

A sensor arrangement for position determination of a rail vehicle includes at least two sensors that can be attached to the rail vehicle. Each of the sensors is configured to ascertain a position speed and to be disposed on the rail vehicle at different positions transverse to the direction of travel. At least one processing apparatus which is connected to the sensors is configured to process the position speeds ascertained by the sensors. An apparatus for position determination of a rail vehicle, a rail vehicle, and a method for position determination for a rail vehicle are also provided.

Claims

1. A sensor arrangement for position determination of a rail vehicle, the sensor arrangement comprising: at least two sensors for ascertaining a position speed of the rail vehicle, said at least two sensors configured to be attached to the rail vehicle at mutually different positions transverse to a direction of travel of the rail vehicle; and at least one processing apparatus configured to process the position speeds ascertained by said at least two sensors.

2. The sensor arrangement according to claim 1, wherein at least one of said at least two sensors is an incremental distance indicator to be connected to a wheel not connected through a rigid axle to an opposite wheel transverse to the direction of travel of the rail vehicle.

3. The sensor arrangement according to claim 1, wherein at least one of said at least two sensors is an optical or inductive sensor.

4. The sensor arrangement according to claim 1, wherein said at least two sensors are configured to be disposed opposite each other transverse to the direction of travel of the rail vehicle.

5. The sensor arrangement according to claim 1, wherein said at least two sensors are configured to be disposed between two wheels of the rail vehicle as viewed in the direction of travel of the rail vehicle.

6. The sensor arrangement according to claim 1, wherein said at least two sensors disposed transverse to the direction of travel of the rail vehicle are separated by an identical distance from a midpoint of the rail vehicle.

7. The sensor arrangement according to claim 1, wherein the sensor arrangement is configured to ascertain an angular velocity ω of the rail vehicle.

8. The sensor arrangement according to claim 7, wherein the sensor arrangement is configured to ascertain the angular velocity ω of the rail vehicle by using a formula $\omega =\frac{v_1-v_2}{\Delta r},$ where v.sub.1 and v.sub.2 are position speeds ascertained by using said at least two sensors and Δr is a separation of said at least two sensors from each other.

9. The sensor arrangement according to claim 1, wherein the sensor arrangement is configured to ascertain an average speed of the rail vehicle.

10. An apparatus for position determination of a rail vehicle, the apparatus comprising: at least one satellite navigation apparatus configured to provide GNSS data; at least one sensor arrangement according to claim 1; and at least one checking apparatus configured to check the GNSS data provided by said satellite navigation apparatus or a position ascertained from the GNSS data provided by said satellite navigation apparatus.

11. The apparatus according to claim 10, wherein said checking apparatus is configured to compare an angular velocity ascertained by using the GNSS data with an angular velocity ascertained by the at least one sensor arrangement and to trigger an action when a difference between the angular velocities exceeds a predetermined limit value.

12. A rail vehicle, comprising at least one sensor arrangement according to claim 1.

13. A rail vehicle, comprising at least one apparatus for position determination according to claim 10.

14. A method for position determination of a rail vehicle, the method comprising: ascertaining at least two position speeds at respectively different positions of the rail vehicle transverse to a direction of travel of the rail vehicle; and processing and using the at least two position speeds for the position determination of the rail vehicle.

15. The method according to claim 14, which further comprises ascertaining at least one of an angular velocity ω or an average speed of the rail vehicle.

16. The method according to claim 14, which further comprises using at least one satellite navigation apparatus of the rail vehicle to provide GNSS data, and checking the GNSS data or a position ascertained from the GNSS data.

Description

BRIEF DESCRIPTION OF THE FIGURE

[0028] The single FIGURE of the drawing is a diagrammatic, perspective view of an exemplary embodiment variant of a rail vehicle according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0029] Referring now in detail to the single FIGURE of the drawing, there is seen an exemplary embodiment variant of a rail vehicle 1 according to the invention. The rail vehicle 1 is part of a railway system 2. In addition to the rail vehicle 1, the railway system 2 also includes a track 3 with rails 4 on which the rail vehicle 1 moves in a direction of travel 5. The rail vehicle 1 can be e.g. a long-distance train, freight train, regional train, underground train or tram and is embodied in a customary manner. The rail vehicle 1 therefore includes a multiplicity of wheels 6, of which only some are illustrated by way of example and which are in contact with the rails 4 in a customary manner. The rail vehicle 1 further includes at least one sensor arrangement 7 and a satellite navigation apparatus 8.

[0030] The satellite navigation apparatus 8 is embodied in a customary manner and determines GNSS data from signals of satellites 9. The GNSS data allows a position of the rail vehicle 1 to be ascertained in a customary manner. The abbreviation GNSS stands for Global Navigation Satellite System. Known examples of satellite navigation systems based on GNSS include the European system Galileo, the American system GPS or the Russian system GLONASS. It is possible to ascertain the position of the rail vehicle 1 on the basis of the GNSS data ascertained by the satellite navigation apparatus 8. This can be performed either directly by the satellite navigation apparatus 8 or by a computing unit 10 which is situated in the rail vehicle 1. The computing unit 10 can be part of an on-board computer, for example. However, the position of the rail vehicle 1 as ascertained by using the GNSS data can be erroneous. That can occur as a result of so-called spoofing, for example, when incorrect position data is ascertained as a result of interference signals.

[0031] The rail vehicle 1 of the present invention has the sensor arrangement 7 in order to counter that problem. The sensor arrangement 7 includes two sensors 11 and a processing apparatus 12.

[0032] The sensors 11 are each configured to ascertain a position speed and are disposed at different positions on the rail vehicle 1. The position speed in this case is understood to mean the speed relative to the track 3 that is ascertained by the respective sensors 11 for a specific position on the rail vehicle 1.

[0033] The sensors 11 can be configured in each case as incremental distance indicators connected to a wheel 6, optical or inductive sensors, for example. In the case of the embodiment as an incremental distance indicator, the sensor is connected to a wheel 6 of the rail vehicle 1 so that the movement of the wheel 6 is captured by the incremental distance indicator and the speed at the position of the wheel 6 can be ascertained thereby. The incremental distance indicator must be disposed at a wheel 6 which is not connected through a rigid axle to the corresponding opposite wheel 6 transverse to the direction of travel 5. Otherwise the measured position speed would be distorted in a curve. In the case of an embodiment as an optical sensor, the sensor captures e.g. the movement of the rail vehicle 1 at the corresponding position relative to the rail head of the corresponding rail 4. In the case of the embodiment as an inductive sensor, the sensor can capture e.g. the traversed rail base fixings and thereby the distance covered and the position speed.

[0034] The sensors 11 are ideally disposed directly opposite each other, transverse to the direction of travel 5, and have an identical separation from a midpoint 13 of the rail vehicle 1. In the case of the exemplary embodiment variant shown in the FIGURE, the sensors 11 are also disposed in each case between two wheels 6 of the rail vehicle 1 as viewed in the direction of travel 5. In this case, the sensors 11 are situated on substantially the same line as the wheels 6, in such a way that the sensors 11 are disposed above the respective rails 4 of the track 3 in each case.

[0035] The sensor arrangement 7 according to the present invention ascertains an angular velocity of the rail vehicle 1 from the position speeds v.sub.1, v.sub.2. The angular velocity ω can be ascertained by using the formula w=v.sub.1−v.sub.2/Δr, where v.sub.1 and v.sub.2 are the position speeds ascertained by using the sensors and Δr is the separation of the sensors from each other. The angular velocity can be ascertained either by the sensor arrangement 7 itself or by the computing unit 10. For example, the computing unit 10 can then use the angular velocity ω ascertained by the sensor arrangement 7 to check the GNSS data of the satellite navigation apparatus 8. An angular velocity of the rail vehicle 1 can also be ascertained from the GNSS data. The two ascertained angular velocities can then be compared with each other. A checking apparatus 14 is provided within the computing unit 10 for this purpose, and is configured to check the GNSS data provided by the satellite navigation apparatus 8 or a position ascertained therefrom. The checking apparatus 14 triggers an alarm if a difference between the angular velocity ascertained from GNSS data and the angular velocity ascertained from the position speeds exceeds a predetermined limit value.

[0036] The sensor arrangement 7, the satellite navigation apparatus 8 and the checking apparatus 14 together form an apparatus 15 according to the present invention for position determination of the rail vehicle 1.

[0037] The sensor arrangement 7 according to the present invention can also be used to ascertain an average speed. On a rail vehicle 1, when travelling around curves, the speed at the position of the inner wheels of the curve is lower, and at the position of the outer wheels 6 of the curve is higher, than the average speed at the midpoint 13. Therefore the average speed can advantageously be used because, even when travelling around curves, it is not distorted.