Train integrity checking method and system based on integrated navigation

Abstract

The invention provides a train integrity checking method and system based on integrated navigation. The method comprises the steps that first train motion state data corresponding to the train head of a train and second train motion state data corresponding to the train tail of the train are obtained respectively; calculating a difference value between the first train motion state data and the second train motion state data, and when the difference value is greater than a set threshold value and is kept for a period of time, judging that the integrity of the train is lost; wherein when the train cannot receive the satellite signal or the failure time of the received satellite signal is greater than or equal to a time critical value, the first train motion state data is first acceleration information corresponding to the train head, and the second train motion state data is second acceleration information corresponding to the train tail. According to the invention, the accuracy, safety and reliability of train integrity inspection are improved, and the integrity of the train can be effectively judged during emergency braking.

Description

Technical Field

[0001] The invention belongs to the field of rail transportation, and in particular relates to a train integrity inspection method and system based on combined navigation. Background Art

[0002] Trains have the characteristics of high running speed, heavy load, and long braking distance. When abnormalities are found ahead (such as a train stopping), safety accidents will inevitably occur if only relying on naked eye observation. The train control system manages train operation through technical means to keep the train running interval. Even if the front train stops suddenly, the rear train will not cause a "rear-end collision accident." The train integrity monitoring system is the core basic function of the train control system. Whether the train integrity monitoring is accurate and safe directly determines the safety and efficiency of the entire train control system. The train integrity monitoring system is an important part of ensuring the safe operation of the train.

[0003] At present, most railway trains use a tail wind pressure detection device to detect the wind pressure of the train. The tail wind pressure detection device sends the tail wind pressure to the driver's locomotive via wireless communication. The driver manually judges whether the train is intact by comparing the wind pressure value at the front and rear of the train.

[0004] However, the above method has the following limitations: (1) Existing train models may not have a reserved interface for the wind pressure detection device at the rear of the train, which makes installation and use difficult. (2) When the train is in emergency braking, the wind pressure at the front and rear of the train is 0, and the train integrity cannot be judged according to the above method. At this time, the integrity is unknown; at the same time, when the train is in emergency braking, the train is more likely to break, and the above integrity judgment method has a major safety hazard. (3) The existing judgment of train integrity relies on manual comparison. If the driver cannot judge whether the train has integrity in the first time, huge losses may occur. (4) Due to squeezing and other reasons, the wind pressure of the air duct of the wind pressure detection device at the rear of the train has not dropped significantly. At this time, the driver cannot judge the integrity of the train by comparing the wind pressure values, resulting in a situation where the train integrity has been lost but the driver is unaware of it, which poses a major safety hazard. Summary of the invention

[0005] The purpose of the present invention is to provide a train integrity inspection method and system based on integrated navigation, which does not require the collection of wind pressure data and will not damage the existing train structure. By calculating the difference in satellite positioning data or acceleration information, the accuracy, safety and reliability of the train integrity inspection are greatly improved, and the integrity of the train can also be effectively judged during emergency braking.

[0006] To achieve the above-mentioned purpose, the present invention provides a train integrity inspection method based on combined navigation, which includes: respectively obtaining first train motion state data corresponding to the head of the train and second train motion state data corresponding to the end of the train; calculating the difference between the first train motion state data and the second train motion state data, and when the difference is greater than a set threshold and maintained for a period of time, it is determined that the integrity of the train is lost; wherein, when the train cannot receive a satellite signal or the failure time of the received satellite signal is greater than or equal to a time critical value, the first train motion state data is the first acceleration information corresponding to the head of the train, and the second train motion state data is the second acceleration information corresponding to the end of the train; when the train receives a satellite signal or the failure time of the satellite signal received by the train is less than the time critical value, the first train motion state data is the first longitude and latitude information and the first speed information corresponding to the head of the train, and the second train motion state data is the second longitude and latitude information and the second speed information corresponding to the end of the train.

[0007] Optionally, the acceleration difference between the train head and the train tail is calculated based on the first acceleration information and the second acceleration information. When the acceleration difference is greater than a first threshold value A and remains for a first time period T1, it is determined that the train integrity is lost; wherein the range of the first threshold value A is 0.2 m / s 2 ~0.5m / s 2 , the range of the first time period T1 is greater than or equal to 5s.

[0008] Preferably, when the speed of the train is less than or equal to 5 km / h, the first threshold value A is 0.5 m / s 2 ; When the speed of the train is greater than 5km / h, the first threshold A is 0.5m / s 2 .

[0009] Optionally, the time threshold is less than or equal to 1 minute.

[0010] Optionally, the difference between the train length and the actual train length is calculated based on the first longitude and latitude information and the second longitude and longitude information, and when the train length difference is greater than a second threshold value L and maintained for a second time period T2, it is determined that the integrity of the train is lost; wherein, the second threshold value L is less than or equal to 100 meters, and the second time period T2 is greater than or equal to 2s.

[0011] Optionally, a formula for calculating the train length according to the first longitude and latitude information and the second longitude and latitude information is as follows:

[0012] y=R×(φ hot -φ eot )

[0013]

[0014] Among them, the φhot is the longitude of the first column, φ eot is the longitude of the column tail, λ hot is the dimension of the column head, λ eot is the latitude of the train end, L is the calculated train length, and R is the radius between the North and South Poles of the Earth.

[0015] Optionally, the speed difference between the head and the tail of the train is calculated based on the first speed information and the second speed information, and when the speed difference is greater than a third threshold value V and maintained for a third time period T3, it is determined that the integrity of the train is lost; wherein the third threshold value V is greater than or equal to 5km / h, and the third time period T3 is greater than or equal to 2s.

[0016] The present invention also provides a train integrity inspection system based on integrated navigation, which comprises: a vehicle-mounted device and a train-end device in communication connection; the vehicle-mounted device is arranged at the head of the train, and comprises: a satellite receiving module, which is in communication connection with at least one satellite, and is used to receive the satellite positioning data of the head of the train, and the satellite positioning data of the head of the train includes first latitude and longitude information and first speed information; an accelerometer module, which is used to measure the first acceleration information of the head of the train; a first main control unit module, which is connected with the satellite receiving module and the accelerometer module, and is used to receive the satellite positioning data of the head of the train and the first acceleration information to form first train motion state data;

[0017] The tail device is arranged at the tail of the train, and comprises: an integrated navigation module, which comprises a global navigation satellite system unit and an inertial measurement unit; the global navigation satellite system unit is connected to the satellite communication, and is used to receive the tail satellite positioning data, and the tail satellite positioning data comprises second latitude and longitude information and second speed information; the inertial measurement unit is used to measure the second acceleration information of the tail; a second main control unit module is connected to the integrated navigation module, and is used to receive the tail satellite positioning data and the second acceleration information to form second train motion state data, and send the second train motion state data to the first main control unit module;

[0018] The first main control unit module calculates the difference between the first train motion state data and the second train motion state data, and when the difference is greater than a set threshold and remains for a period of time, it is determined that the integrity of the train is lost.

[0019] Optionally, the vehicle-mounted device further includes a first wireless communication module, and the tail-end device further includes a second wireless communication module, and the first communication module and the second communication module are connected to form a wireless communication network between the vehicle-mounted device and the tail-end device.

[0020] In summary, compared with the prior art, the train integrity inspection method and system based on combined navigation provided by the present invention has the following beneficial effects: the train integrity is inspected and judged by using the first acceleration information and the second acceleration information measured by the inertial measurement unit in the accelerometer module at the head of the train and the combined navigation module at the tail of the train, so that the train integrity can still be judged when the satellite signal fails, thereby improving the accuracy, safety and reliability of the train integrity inspection; at the same time, when the validity and timeliness of the satellite signal meet the requirements, the train integrity can also be inspected and judged by the longitude and latitude information and speed information at the head and tail of the train, without adding an additional wind pressure detection device at the tail of the train, thus avoiding damage to the structure of the existing train, making installation and use more convenient, and the train integrity can also be judged during emergency braking. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A connection block diagram of a train integrity inspection system based on integrated navigation of the present invention;

[0022] Figure 2 The present invention is a flow chart of a train integrity inspection method based on integrated navigation.

[0023] Description of reference numerals:

[0024] 100 vehicle equipment

[0025] 101 satellite receiving module

[0026] 102 Accelerometer Module

[0027] 103 first main control unit module

[0028] 104 first wireless communication module

[0029] 200 tail equipment

[0030] 201 combined navigation module

[0031] 211 Global Navigation Satellite System Unit

[0032] 212 Inertial Measurement Unit

[0033] 203 Second main control unit module

[0034] 204 second wireless communication module

[0035] 300 satellites DETAILED DESCRIPTION

[0036] The following will be combined with the attached embodiment of the present invention Figure 1 ~Attached Figure 2, the technical solutions, structural features, objectives achieved and effects in the embodiments of the present invention are described in detail.

[0037] It should be noted that the drawings are in a very simplified form and use non-precise proportions. They are only used to conveniently and clearly assist in explaining the embodiments of the present invention, and are not used to limit the conditions for the implementation of the present invention. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0038] It should be noted that, in the present invention, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only the elements explicitly listed, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0039] To improve the accuracy, safety and reliability of train integrity inspection, Figure 1 As shown, the present invention provides a train integrity inspection system based on combined navigation, which includes: a vehicle-mounted device 100 and a tail device 200 that are communicatively connected; the vehicle-mounted device 100 is arranged at the head of the train, and includes: a satellite receiving module 101, which is communicatively connected to at least one satellite 300 and is used to receive the satellite positioning data of the head of the train, and the satellite positioning data of the head of the train includes first longitude and latitude information and first speed information; an accelerometer module 102, which is used to measure the first acceleration information of the head of the train; a first main control unit module 103, which is connected to the satellite receiving module 101 and the accelerometer module 102, and is used to receive the satellite positioning data of the head of the train and the first acceleration information to form first train motion state data.

[0040] Among them, Figure 1As shown, the tail device 200 is arranged at the tail of the train, and comprises: a combined navigation module 201, which comprises a global navigation satellite system unit 211 and an inertial measurement unit 212; the global navigation satellite system unit 211 is connected to the satellite 300 for communication, and is used to receive the tail satellite positioning data, and the tail satellite positioning data comprises the second latitude and longitude information and the second speed information; the inertial measurement unit 212 is used to measure the second acceleration information of the tail; the second main control unit module 203 is connected to the combined navigation module 201, and is used to receive the tail satellite positioning data and the second acceleration information to form the second train motion state data, and send the second train motion state data to the first main control unit module 103. Further, the first main control unit module 103 calculates the difference between the first train motion state data and the second train motion state data, and when the difference is greater than the set threshold and remains for a period of time, it is determined that the integrity of the train is lost.

[0041] Among them, Figure 1 As shown, the vehicle-mounted device 100 further includes a first wireless communication module 104, and the tail device 200 further includes a second wireless communication module 204. The first communication module 104 and the second communication module 204 are connected to form a wireless communication network of the vehicle-mounted device 100 and the tail device 200, thereby realizing the interactive transmission of the first train motion state data and the second train motion state data. By setting the wireless communication network between the head and tail of the train as the communication channel for train integrity inspection, it is ensured that in the case of satellite communication failure, the wireless communication network between the head and tail of the train can still be used to ensure that the driver can obtain the integrity status of the train in real time.

[0042] The present invention also provides a train integrity inspection method based on integrated navigation, which adopts Figure 1 The train integrity inspection system based on integrated navigation shown in FIG. 1 inspects the train integrity. Figure 2 As shown, the train integrity inspection method includes:

[0043] S1. The vehicle-mounted device 100 obtains first train motion state data and second train motion state data corresponding to the head and the tail of the train respectively;

[0044] S2, the first main control unit module 103 calculates the difference between the first train motion state data and the second train motion state data, and when the difference is greater than a set threshold and remains for a period of time, it is determined that the integrity of the train is lost;

[0045] When the train fails to receive satellite signals or the failure time of the received satellite signals is greater than or equal to the time critical value, the first train motion state data is the first acceleration information a corresponding to the train head. hotThe second train motion state data is the second acceleration information a corresponding to the end of the train. eot When the train receives a satellite signal or the failure time of the satellite signal received by the train is less than the time critical value, the first train motion state data is the first latitude and longitude information and the first speed information v corresponding to the column head. hot (i.e., satellite positioning data), the second train motion state data is the second latitude and longitude information and the second speed information v corresponding to the end of the train eot (i.e. satellite positioning data).

[0046] To ensure the validity of the satellite signal, in this embodiment, when the train receives the satellite signal, the satellite signal status data contained in the satellite signal can be used to determine the validity of the satellite signal to ensure the accuracy of the train integrity check. At the same time, since the satellite signal has a certain timeliness, it is also necessary to determine the expiration time of the satellite signal, and to determine whether the expiration time of the satellite signal exceeds the time threshold. This is because the speed information and longitude and latitude information at the head and tail of the train are provided by the satellite signal. If the validity or timeliness of the satellite signal is lost, the speed information and longitude and latitude information cannot be used to check and determine the train integrity.

[0047] When the train fails to receive satellite signals or the failure time of the received satellite signals is greater than or equal to the time critical value, the first acceleration information a corresponding to the column head can be used to hot The second acceleration information a corresponding to the end of the column eot The train integrity is checked and judged. This is because the acceleration information at the head and tail of the train is measured by the accelerometer module 102 arranged at the head of the train and the inertial measurement unit 212 arranged at the tail of the train. Therefore, when no satellite signal is received or the failure time of the satellite signal is greater than the time threshold, the train integrity can still be checked and judged through the acceleration information.

[0048] As an optional embodiment, the time critical value is less than or equal to 1 minute. This is because within the time critical value, the recursive cumulative error of the accelerometer module 102 and the inertial measurement unit 212 is small, thereby improving the accuracy of the train integrity check.

[0049] When the train fails to receive satellite signals or the received satellite signals have been invalid for more than 1 minute, the train is automatically reset according to the first acceleration information a corresponding to the train head. hot The second acceleration information a corresponding to the end of the column eot The acceleration difference Δa between the train head and the train tail is calculated. When the acceleration difference Δa is greater than a first threshold value A and is maintained for a first time period T1, it is determined that the integrity of the train is lost. Specifically, Figure 2As shown, it includes: step S211, judging whether the acceleration difference Δa is greater than the first threshold value A, if the acceleration difference Δa is greater than the first threshold value A, executing step S212; otherwise, executing step S213; step S212, performing a first timing on the duration that the acceleration difference Δa is greater than the first threshold value A, if the first timing time t1 is greater than the first time period T1, it is determined that the integrity of the train is lost; step S213, ending the first timing and ending the train integrity check.

[0050] The range of the first threshold A is 0.2 m / s 2 ~0.5m / s 2 , the range of the first time period T1 is greater than or equal to 5s (seconds). That is, when the acceleration difference Δa between the front and rear of the train is greater than or equal to 0.2m / s 2 ~0.5m / s 2 When the acceleration difference Δa is maintained for a time greater than or equal to 5s, the train integrity is determined to be lost.

[0051] Preferably, when the speed of the train is less than or equal to 5 km / h, the first threshold value A is 0.5 m / s 2 When the train speed is greater than 5 km / h, the first threshold A is 0.2 m / s 2 . This is because when the train speed is low (less than or equal to 5km / h), it has less kinetic energy, so the braking distance of the train is also shorter. In this case, even if the acceleration difference is large, it may be caused by some non-serious factors (such as slight bumps or normal expansion and contraction of the carriage connection), so a larger first threshold A can be set to avoid misjudgment. On the contrary, when the train speed is high, it has greater kinetic energy, and the train requires a longer braking distance and response time to stop safely. Therefore, for trains with higher running speeds (greater than 5km / h), the first threshold A corresponding to the acceleration difference between the head and the tail of the train needs to be set smaller to ensure that when there is an abnormality in the train integrity, it can be detected in time and corresponding measures can be taken.

[0052] When the train receives a satellite signal or the failure time of the received satellite signal is less than 1 minute, the train length can be calculated according to the first longitude and latitude information and the second longitude and latitude information, and the difference ΔL between the train length and the actual train length can be calculated. When the difference ΔL is greater than the second threshold value L and is maintained for the second time period T2, it is determined that the integrity of the train is lost. Specifically, Figure 2As shown, it includes: step S221, calculating the train length according to the first longitude and latitude information and the second longitude and latitude information, and judging whether the difference ΔL between the train length and the actual length is greater than the second threshold L. If the difference ΔL is greater than the second threshold L, then executing step S222; otherwise, executing step S223; step S222, performing a second timing for the duration of the difference ΔL being greater than the second threshold L, and if the second timing time t2 is greater than the second time period T2, then judging that the integrity of the train is lost; step S223, ending the second timing and ending the train integrity check. Among them, the second threshold L is less than or equal to 100 meters, and the second time period T2 is greater than or equal to 2s. This is because the coupler may change due to stretching or compression during the running of the train, and this change is usually within a certain range. By setting the second threshold L of 100 meters, it can be used as a safety redundancy to ensure that even in the case of large changes in the extension and contraction of the coupler, the integrity judgment of the train can be kept within a safe range. By setting the second threshold L to be less than or equal to 100 meters, while ensuring the safe operation of the train, misjudgments caused by errors can be reduced, thereby improving the practicality and reliability of the train integrity check.

[0053] Further, the formula for calculating the train length according to the first longitude and latitude information and the second longitude and latitude information is as follows:

[0054] y=R×(φ hot -φ eot )

[0055]

[0056] Among them, the φ hot is the longitude of the first column, φ eot is the longitude of the column tail, λ hot is the dimension of the column head, λ eot is the latitude of the train end, L is the calculated train length, and R is the radius between the North and South Poles of the Earth.

[0057] Furthermore, when the train receives a satellite signal or the failure time of the received satellite signal is less than 1 minute, the train can also receive the first speed information v hot and the second velocity information v eot The speed difference Δv between the head and the tail of the train is calculated. When the speed difference Δv is greater than a third threshold value V and is maintained for a third time period T3, it is determined that the integrity of the train is lost. Specifically, Figure 2As shown, it includes: step S231, judging whether the speed difference Δv between the head and the tail of the train is greater than the third threshold value V, if the speed difference Δv is greater than the third threshold value V, executing step S232; otherwise, executing step S233; step S232, performing a third timing for the duration of the speed difference Δv greater than the third threshold value V, if the third timing time t3 is greater than the third time period T3, it is determined that the integrity of the train is lost; step S233, ending the third timing, and ending the train integrity check. Among them, the third threshold value V is greater than or equal to 5km / h, and the third time period T3 is greater than or equal to 2s. This is because when the train is running, if the speed difference Δv between the head and the tail of the train exceeds 5km / h, it usually means that a part of the train has been separated from the main body, such as a decoupling situation. Such a speed difference is sufficient to indicate that the integrity of the train has been affected, and immediate measures need to be taken to ensure safety. By setting the third threshold value V to be greater than or equal to 5km / h, the safety of train operation is ensured, while reducing false alarms and improving the accuracy and reliability of train integrity checks.

[0058] In summary, the train integrity inspection method and system based on combined navigation provided by the present invention inspects and judges the train integrity by using the first acceleration information and the second acceleration information measured by the accelerometer module 102 at the head of the train and the inertial measurement unit 212 in the combined navigation module 201 at the tail of the train, thereby achieving the judgment of the train integrity when the satellite signal fails, thereby improving the accuracy, safety and reliability of the train integrity inspection; at the same time, when the validity and timeliness of the satellite signal meet the requirements, the train integrity can also be inspected and judged by the longitude and latitude information and speed information at the head and tail of the train, without adding an additional wind pressure detection device at the tail of the train, thus avoiding damage to the structure of the existing train, and making installation and use more convenient, and the train integrity can also be judged during emergency braking.

[0059] Although the content of the present invention has been described in detail through the above preferred embodiments, it should be appreciated that the above description should not be considered as a limitation of the present invention. After reading the above content, it will be apparent to those skilled in the art that various modifications and substitutions of the present invention will occur. Therefore, the protection scope of the present invention should be limited by the appended claims.

Claims

1. A train integrity inspection method based on integrated navigation, characterized in that: include: Respectively obtaining first train motion state data corresponding to the head of the train and second train motion state data corresponding to the tail of the train; Calculating a difference between the first train motion state data and the second train motion state data, and when the difference is greater than a set threshold and remains for a period of time, determining that the integrity of the train is lost; Wherein, when the train cannot receive the satellite signal or the failure time of the received satellite signal is greater than or equal to the time critical value, the first train motion state data is the first acceleration information corresponding to the head of the train, and the second train motion state data is the second acceleration information corresponding to the tail of the train; When the train receives a satellite signal or the failure time of the satellite signal received by the train is less than the time critical value, the first train motion status data is the first longitude and latitude information and the first speed information corresponding to the head of the train, and the second train motion status data is the second longitude and latitude information and the second speed information corresponding to the end of the train.

2. The train integrity inspection method according to claim 1, characterized in that: The acceleration difference between the train head and the train tail is calculated based on the first acceleration information and the second acceleration information. When the acceleration difference is greater than a first threshold value A and is maintained for a first time period T1, it is determined that the train integrity is lost; wherein the range of the first threshold value A is 0.2 m / s 2 ~0.5m / s 2 , the range of the first time period T1 is greater than or equal to 5s.

3. The train integrity inspection method according to claim 2, characterized in that: When the speed of the train is less than or equal to 5 km / h, the first threshold A is 0.5 m / s 2 When the train speed is greater than 5 km / h, the first threshold A is 0.2 m / s 2 .

4. The train integrity inspection method according to claim 1, characterized in that: The time critical value is less than or equal to 1 minute.

5. The train integrity inspection method according to claim 1, characterized in that: The train length is calculated according to the first longitude and latitude information and the second longitude and latitude information, and the difference between the train length and the actual length is calculated. When the difference in length is greater than a second threshold value L and is maintained for a second time period T2, it is determined that the integrity of the train is lost; wherein the second threshold value L is less than or equal to 100 meters, and the second time period T2 is greater than or equal to 2s.

6. The train integrity inspection method according to claim 5, characterized in that: The formula for calculating the train length according to the first longitude and latitude information and the second longitude and latitude information is as follows: y=R×(φ hot -f eot ) Among them, the φ hot is the longitude of the first column, φ eot is the longitude of the column tail, λ hot is the dimension of the column head, λ eot is the latitude of the train end, L is the calculated train length, and R is the radius between the North and South Poles of the Earth.

7. The train integrity inspection method according to claim 1, characterized in that: The speed difference between the head and the tail of the train is calculated based on the first speed information and the second speed information. When the speed difference is greater than a third threshold value V and maintained for a third time period T3, it is determined that the integrity of the train is lost; wherein the third threshold value V is greater than or equal to 5 km / h, and the third time period T3 is greater than or equal to 2 s.

8. A train integrity inspection system based on integrated navigation, characterized in that: include: On-board equipment and rear-end equipment with communication connection; The on-board device is arranged at the head of the train, and comprises: a satellite receiving module, which is connected to at least one satellite for communication and is used to receive the satellite positioning data at the head of the train, wherein the satellite positioning data at the head of the train comprises first latitude and longitude information and first speed information; an accelerometer module, used to measure the first acceleration information of the train head; a first main control unit module, connected to the satellite receiving module and the accelerometer module, used to receive the satellite positioning data of the train head and the first acceleration information to form the first train motion state data; The tail device is arranged at the tail of the train, and comprises: an integrated navigation module, which comprises a global navigation satellite system unit and an inertial measurement unit; the global navigation satellite system unit is connected to the satellite communication, and is used to receive the tail satellite positioning data, and the tail satellite positioning data comprises second latitude and longitude information and second speed information; the inertial measurement unit is used to measure the second acceleration information of the tail; a second main control unit module is connected to the integrated navigation module, and is used to receive the tail satellite positioning data and the second acceleration information to form second train motion state data, and send the second train motion state data to the first main control unit module; The first main control unit module calculates the difference between the first train motion state data and the second train motion state data, and when the difference is greater than a set threshold and remains for a period of time, it is determined that the integrity of the train is lost.

9. The train integrity inspection system according to claim 8, characterized in that: The vehicle-mounted device further includes a first wireless communication module, and the tail-end device further includes a second wireless communication module. The first communication module and the second communication module are connected to form a wireless communication network between the vehicle-mounted device and the tail-end device.

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