WO2018232129A1

WO2018232129A1 - Crossing warning adjustment system and method

Info

Publication number: WO2018232129A1
Application number: PCT/US2018/037563
Authority: WO
Inventors: Scott A. SOLLARS; Timothy Allen SCHULTZ; Michael W. II STEFFEN
Original assignee: Westinghouse Air Brake Technologies Corporation
Priority date: 2017-06-15
Filing date: 2018-06-14
Publication date: 2018-12-20

Abstract

A crossing warning adjustment system for enforcing a constant warning time at an associated crossing grade in a geographic location for a train approaching the crossing grade, including an on-board train system configured to communicate with one or more wayside devices based on track data for an approach to the crossing grade, the one or more wayside devices controlling a crossing warning device, and the crossing warning device configured to control a trains approach to a crossing warning, the crossing warning adjustment system including one or more processors to determine a time-to-crossing associated with a train, determine an approach adjustment, based on the track data associated with the crossing grade, and provide a crossing warning, including the approach adjustment to the crossing warning. The approach adjustment to delay a crossing arrival time at a crossing warning to control an approaching train.

Description

CROSSING WARNING ADJUSTMENT SYSTEM AND METHOD

CROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to United States Provisional Application

No. 62/520,220 filed June 15, 2017, the disclosure of which is incorporate in its entirety by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

[0002] The present invention relates to a system and method for adjusting a warning time for wireless crossing warning associated with a crossing grade in a track network. The system controls a constant warning at a crossing warning by adjusting minimum warning times where track circuit predictors are known to be ineffective, and in particular, to a system and method for identifying and using the actual operating conditions of a crossing grade approach (e.g., safety devices, conditions, arrangements, etc.) associated with a track over which a train traverses within a track network approach to a crossing grade.

2. Description of Related Art

[0003] Train control systems are used for monitoring and tracking trains traversing tracks throughout a track network. In order to make appropriate train control decisions regarding how the train should be operated (e.g., manually, automatically, or semi-automatically), important information about the track network must be obtained. Accurate data and knowledge regarding the conditions of the tracks and surrounding areas in the track network is often sparse making control decisions less effective for train operation. Presently, track networks extend throughout all of the countries in the world and include interconnected tracks that extend through both populated and unpopulated areas. For example, many track networks extend through towns, cities, residential areas, etc., such that they intersect other vehicular transit systems (e.g., roadways, busways, etc.). Therefore, and due to the physics and restraints upon operating a train, appropriate safety arrangements are necessary at intersections in order to ensure the safety of vehicles and pedestrians.

[0004] For safety (e.g., train safety, pedestrian safety, automobile safety, etc.), crossing gates are provided at locations where tracks intersect with roadways. Crossing gates are important to warn others and prevent collisions between track vehicles (e.g., train and/or the like) and automobiles. Crossing gates are used to impede automobiles, pedestrians, and other track vehicles from crossing the tracks while a track vehicle is traveling on the tracks at or near the crossing.

[0005] Crossing gates use a warning predictor to detect a motion of a train toward a crossing (e.g., a track circuit, wayside devices, etc.) to estimate a train's time at approach to meet the configured warning time. Warning predictors for a train (e.g., time-to-crossing (TTC)) activate a crossing warning device (e.g., lights, gates, bells, etc.) for a specified minimum amount of time prior to train arrival at the crossing (e.g.,., the required time-to-crossing (RTTC)). However, warning prediction systems are not configured to accurately and efficiently predict delays based on conditions of the track, the environment surrounding the track, history of a section of track, and/or the like and require that a crossing gate be designed to close at a set time exceeding a desired time for closing in order to account for delays.

[0006] The amount of warning time a train needs for a crossing grade may vary widely. For example, if a train computer delays activation of a warning device because a train is moving slower than a maximum track speed, and then the train accelerates toward a track grade crossing, it could create a situation where the warning is not provided. In another example, if track circuits merely activate a crossing gate based on train occupancy, a warning time provided at a crossing gate can vary significantly depending upon train speed. These warning systems, however, fail to address issues resulting from relatively slower speeds and inconsistent wait times at crossings.

[0007] These warning systems may create long warning times that are inefficient and inaccurate due to unnecessary delay and may provoke impatient motorists to drive around crossing gates and/or disregard audible or visible warnings if the motorists do not see any trains approaching after some period of time. As a result, traffic along a highway and through a crossing gate may be stopped unnecessarily causing unnecessary and inconsistent delays while a train proceeds. Repeated inconsistencies with warnings at a particular gate in an unsynchronized manner may confuse motorists and result in unsafe and high risk driving behavior.

SUMMARY OF THE INVENTION

[0008] Generally, provided is a system, method, and apparatus for adjusting crossing activations based on a time for a train to traverse a crossing warning approach without exceeding or subceeding a predetermined warning time enough to cause excessive warning times at the track crossing grade. Preferably, provided is a system, method, and apparatus where accounting for conditions along the route can be made through an adjustment factor. Preferably, provided is a system, method, and apparatus where characteristics and conditions of the route and track have been sensed, measured, captured, and are used to communicate with a crossing grade to modify the effective range of the approach by using an approach condition adjustment factor (e.g., an approach adjustment, etc.) for adjusting actual crossing grade warnings, and by causing the actual wait times to converge on a minimum wait time.

[0009] According to some non-limiting embodiments or aspect, provided is a computer-implemented method for adjusting warning times at a crossing grade for approaching trains. The method includes: (a) receiving track data associated with the crossing grade in a geographic location; (b) determining a time-to-crossing associated with a train; (c) determining an approach adjustment, based on the track data associated with the crossing grade; (d) adjusting the time-to-crossing time upon determination of the approach adjustment; and (e) providing a crossing warning, including the approach adjustment, wherein the approach adjustment controls the crossing grade to delay a crossing arrival time.

[0010] In some non-limiting embodiments or aspect, the method further includes: (f) controlling the train to reach the crossing at the adjusted TTC.

[0011] In some non-limiting embodiments or aspect, the adjusting is performed only when a required crossing warning time precedes a TTC.

[0012] In some non-limiting embodiments or aspects, the method further includes adjusting only if there is a threshold difference between a required crossing warning time and a TTC.

[0013] In some non-limiting embodiments or aspects, the method further includes a determination made when a difference exists between a predicted crossing warning time and a required crossing warning time.

[0014] In some non-limiting embodiments or aspects, the method further includes determining by testing if the approach adjustment exists for the approaching crossing.

[0015] In some non-limiting embodiments or aspects, the method further includes testing if the approach adjustment exists for a particular direction of the train approaching the crossing. [0016] In some non-limiting embodiments or aspects, the method further includes an approach adjustment that is stored in the on-board control system, a wayside device, or a central system.

[0017] In some non-limiting embodiments or aspects, the method further includes displaying an adjusted arrival time on the train; receiving an arrival warning; and controlling the train to arrive at the crossing based on the arrival warning.

[0018] In some non-limiting embodiments or aspects, the method further includes a visible speed limit to follow displayed on the train.

[0019] In some non-limiting embodiments or aspects, the method further includes an on-board system that enforces speed limits to reach the crossing at the adjusted time.

[0020] In some non-limiting embodiments or aspect, provided is a crossing grade adjustment system for enforcing constant warning time at a crossing grade using historical track information for predicting train behavior within a crossing approach. The system includes a transmitter configured as part of an on-board train system (e.g., a locomotive control system, etc.) to communicate with a crossing warning start message and to receive crossing information comprising an approach adjustment to change the activation of the crossing and an on-board locomotive processor configured to control a crossing warning based on the crossing information. The onboard processor is programmed or configured to (a) receive the historical track information associated with a crossing grade in a geographic location; (b) determine a TTC associated with a train; (c) determine an approach adjustment, based on the historical track information associated with the crossing grade; (d) adjust the TTC time upon determination of the approach adjustment; and (e) provide a crossing warning, including the approach adjustment to the crossing grade, wherein the approach adjustment controls the crossing grade to delay a crossing arrival time.

[0021] In some non-limiting embodiments or aspects, the transmitter further sends a request message to delay activation of a crossing warning activity at the crossing otherwise called for by information from a track detection system, the message including fields based on a difference between a predicted crossing warning time and a required crossing warning time with an adjustment determination when the required time precedes the crossing warning time.

[0022] In some non-limiting embodiments or aspects, the crossing grade adjustment system further includes a positioning system configured to determine an estimated train position on a track within a track network and approaching the upcoming crossing grade; and at least one track information data source, which comprises at least one of the following: status data, adjustment activation data, adjustment factor data, track direction, condition data, fault data, activity data, or equipment state data, wherein the data source is located in the train and is dynamically updated while the train is traversing a track in a track network.

[0023] In some non-limiting embodiments or aspects, the crossing grade adjustment system is provided, wherein the estimated speed or traveling speed is based on speed restrictions on an approach, having track information associated with at least one approach adjustment associated with a crossing warning.

[0024] In some non-limiting embodiments or aspects, an adjustment determination is based on position or location of the train, speed of the train, and design time over the approach.

[0025] In some non-limiting embodiments or aspects, the track information includes at least one of track segment information and an operating condition of at least one train for at least one approach to a crossing on at least one designated route.

[0026] In some non-limiting embodiments or aspects, the track information comprises crossing activation time results.

[0027] In some non-limiting embodiments or aspects, the time to next crossing is determined using either current speed, estimated speed, or maximum authorized speed.

[0028] In some non-limiting embodiments or aspect, provided is a wayside adjustment control system for adjusting a warning time at a crossing grade using historical track information for predicting train behavior within a crossing approach, the system including a wayside device, and a transmitter. The wayside device of the system is coupled to a crossing warning device, the wayside device receiving periodic request messages from a processing unit of a track vehicle including train-related information comprising a grade crossing arrival. The transmitter is configured as part of a wayside device for track network control to communicate with an on-board train computer with a crossing warning start message and to receive crossing information comprising an approach adjustment to change the activation of the crossing. The wayside device is configured to control approaching trains for a crossing warning based on crossing information, and configured to: (a) receive historical track information associated with a crossing grade in a geographic location; (b) determine a TTC associated with a train; (c) determine an approach adjustment, based on the historical track information associated with the crossing grade; (d) adjust the TTC time upon determination of the approach adjustment; and (e) provide a crossing warning, including the approach adjustment to the crossing grade, wherein the approach adjustment controls the crossing grade to delay a crossing arrival time.

[0029] Clause 1 : A computer-implemented method for adjusting warning times at a crossing grade for approaching trains. The method includes: (a) receiving track data associated with the crossing grade in a geographic location; (b) determining, with a computer system comprising one or more processors, a time-to-crossing associated with a train; (c) determining, with a computer system, an approach adjustment based on the track data associated with the crossing grade; (d) adjusting, with the computer system, the time-to-crossing time upon determination of the approach adjustment; and (e) providing, with the computer system, a crossing warning, including the approach adjustment to the crossing grade, wherein the approach adjustment controls the crossing grade to delay a crossing arrival time.

[0030] Clause 2: The method of clause 1, further comprising: (f) controlling the train to reach the crossing at a required time to arrival.

[0031] Clause 3: The method of any of clauses 1 or 2, wherein adjusting the warning time further comprises determining the crossing warning time precedes the time-to-crossing.

[0032] Clause 4: The method of any of clauses 1-3, wherein adjusting the warning time in response to a threshold difference between a required crossing warning time and a time-to-crossing.

[0033] Clause 5: The method of any of clauses 1-4, wherein determining the approach adjustment comprises determining a difference between a predicted crossing warning time and the required crossing warning time.

[0034] Clause 6: The method of any of clauses 1-5, the determining the approach adjustment further comprises determining if the approach adjustment exists for the approaching crossing.

[0035] Clause 7: The method of any of clauses 1-6, wherein determining an approach adjustment further comprises determining if the approach adjustment exists for a particular direction of travel for the train approaching the crossing. [0036] Clause 8: The method of any of clauses 1-7, wherein the approach adjustment is stored in an on-board control system, a wayside device, or a central system.

[0037] Clause 9: The method of any of clauses 1-8, further comprising: displaying an adjusted arrival time on the train; receiving, from the crossing grade, an arrival warning; and controlling the train to arrive at the crossing based on the arrival warning.

[0038] Clause 10: The method of any of clauses 1-9, wherein displaying an adjusted arrival time further comprises displaying a visible speed limit to follow by the train.

[0039] Clause 11: The method of any of clauses 1-10, wherein an on-board system enforces speed limits to reach the crossing at the adjusted time.

[0040] Clause 12: The crossing grade adjustment system for enforcing a constant warning time at a crossing grade using historical track information for predicting train behavior within a crossing approach, wherein the system comprises a transmitter configured as part of an on-board train system to communicate with a crossing warning start message and to receive crossing information comprising an approach adjustment to change activation of a crossing and an on-board locomotive processor configured to control a crossing warning, having crossing information and configured to (a) receive the historical track information associated with a crossing grade in a geographic location (b) determine a time-to-crossing associated with a train; (c) determine an approach adjustment, based on the historical track information associated with the crossing grade; (d) adjust the time-to-crossing warning time upon determination the approach adjustment; and (e) provide a crossing warning, including the approach adjustment to the crossing grade, wherein the approach adjustment controls the crossing grade to delay a crossing arrival time.

[0041] Clause 13: The crossing grade adjustment system of clause 12, further comprising: the transmitter sending a request message to delay activation of a crossing warning activity at the crossing otherwise called for by information from a track detection system, the message including fields based on a difference between a predicted crossing warning time and a required crossing warning time with an adjustment determination when the required time precedes the crossing warning time.

[0042] Clause 14: The crossing grade adjustment system of any of clauses 12 or 13, further comprising: a positioning system configured to determine an estimated train position on a track within a track network and approaching the upcoming crossing grade; and at least one track information data source, which comprises at least one of the following: status data, adjustment activation data, adjustment factor data, track direction, condition data, fault data, activity data, equipment state data, wherein the data source is located in the train and is dynamically updated while the train is traversing a track in a track network.

[0043] Clause 15: The crossing grade adjustment system of any of clauses 12-

14, wherein an estimated speed or traveling speed is comprising speed restrictions on an approach, having track information associated with at least one approach adjustment associated with a crossing warning.

[0044] Clause 16: The crossing grade adjustment system of any of clauses 12-

15, further comprising an adjustment determination is based on position or location of the train, speed of the train, and design time over the approach.

[0045] Clause 17: The crossing grade adjustment system of any of clauses 12-

16, wherein track information comprises at least one of track segment information and an operating condition of at least one train for at least one approach to a crossing on at least one designated route.

[0046] Clause 18: The crossing grade adjustment system of any of clauses 12-

17, wherein track information comprises crossing activation time results.

[0047] Clause 19: The crossing grade adjustment system of any of clauses 12-

18, further comprising the time to next crossing is determined using either current speed, design speed, estimated speed, or maximum authorized speed, maximum legal speed.

[0048] Clause 20: A wayside adjustment system for adjusting a warning time at a crossing grade using historical track information for predicting train behavior within a crossing approach, the system comprising a wayside device, transmitter. The wayside device of the system is coupled to a crossing warning device, the wayside device receiving periodic request messages from a processing unit of a track vehicle containing train-related information comprising a grade crossing arrival. The transmitter is configured as part of a wayside device for track network control to communicate with an on-board train computer with a crossing warning start message and to receive crossing information comprising an approach adjustment to change the activation of the crossing. The wayside device is configured to control approaching trains for a crossing warning, having crossing information and configured to: (a) receive the historical track information associated with a crossing grade in a geographic location; (b) determine a time-to-crossing associated with a train; (c) determine an approach adjustment, based on the historical track information associated with the crossing grade; (d) adjust the time-to-crossing upon determination of the approach adjustment; and (e) provide a crossing warning, including the approach adjustment to the crossing grade, wherein the approach adjustment controls the crossing grade to delay a crossing arrival time.

BRIEF DESCRIPTION OF THE DRAWINGS

[0049] FIG. 1 is a schematic view of one embodiment of a system and method for identifying a condition of an upcoming feature of a track in a track network according to the principles of the present invention;

[0050] FIG. 2 is a schematic view of a further embodiment of a system and method for identifying a condition of an upcoming feature of a track in a track network according to the principles of the present invention;

[0051] FIG. 3 is a schematic view of another embodiment of a method and system for identifying a condition of an upcoming feature of a track in a track network according to the principles of the present invention;

[0052] FIG. 4A is an example of a data set used in an exemplary embodiment of the present invention;

[0053] FIG. 4B is an example of a data set used in an exemplary embodiment of the present invention;

[0054] FIG. 6 is a flowchart of an embodiment of a method for adjusting a track vehicle; and

[0055] FIG. 7A is an example of a display for a train operator used in an exemplary embodiment of the present invention;

[0056] FIG. 7B is an example of a display for a train operator used in an exemplary embodiment of the present invention;

[0057] FIG. 7C is an example of a display for a train operator used in an exemplary embodiment of the present invention;

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0058] For purposes of the description hereinafter, the terms "upper," "lower,"

"right," "left," "vertical," "horizontal," "top," "bottom," "lateral," "longitudinal," and derivatives thereof can relate to the invention as it is oriented in the drawing figures. However, it is to be understood that the invention may assume various alternative variations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification, are simply exemplary embodiments of the invention. Hence, specific dimensions and other physical characteristics related to the embodiments disclosed herein are not to be considered as limiting.

[0059] In some non-limiting embodiments, a train may not traverse a track to reach a crossing grade in an efficient and/or accurate manner. For example, a train may arrive at a crossing grade late, thereby forcing a crossing warning (e.g., a crossing gate, a crossing signal, a crossing alarm, a crossing light, etc.) to continue past a minimum warning time. In another example, trains may reach a crossing grade inconsistently, causing activations of variable duration. In some non-limiting embodiments, a track database (e.g., historical information table 410) includes track data associated with one or more crossing grades (e.g., data associated with a crossing approach, data associated with track conditions, data associated with an environment surrounding a track (e.g. a segment of track), data associated with historical events in a track, etc.). For example, a track database (e.g., historical information table 410) may be provided to determine an approach adjustment from track data (e.g., based on conditions of the track, based on the environment surrounding the track, based on history of a section of track, etc.) to adjust (e.g., optimize, modify, etc.) a crossing approach. For example, a crossing warning adjustment system for a crossing grade may process historical data from historical crossing activation time results to generate an adjustment value. In some non- limiting embodiments, adjustment values may be used to correct inefficient and/or inaccurate crossing grades by minimizing a crossing warning time as a train approaches a crossing grade. As an example, without an approach condition adjustment, a majority of train crossings are not experiencing any crossing guidance except for a change in RTTC and TTC. Additionally, or alternatively, without crossing guidance, trains may be less efficient and/or less accurate, for example, trains are more likely to arrive later than the required time resulting in an excessive warning time.

[0060] Referring now to FIG. 1, FIG. 1 is a diagram of a non- limiting embodiment of a system 10 for identifying one or more time adjustments associated with a crossing grade. As shown in FIG. 1 , system 10 is associated with an upcoming crossing grade 12 of a track T in a track network to eliminate long crossing warning times. In some non-limiting embodiments, track data, captured and analyzed, causes adjustment to an approach time for a crossing grade. For example, system 10 uses adjusted TTC to delay a crossing warning for a time to make the warning more conventional.

[0061] In some non-limiting embodiments, delaying the crossing warning means that a crossing warning is not initialized when a crossing activation message is sent. For example, the system 10 controls the crossing warning activation at a time in the future based on the TTC and RTTC. The system 10 may be utilized to send activation messages to a wayside device with an approach adjustment, such as, by adjusting the TTC that accounts for fluctuation in arrival time and can provide uniform crossing grade warning times.

[0062] In some non-limiting embodiments, a track network includes or is made up of multiple interconnected tracks, where various upcoming features (e.g., devices, equipment, arrangements, implementable actions, etc.) are associated with a portion of the track T. For example, such an upcoming feature may be certain devices, equipment, arrangements, and/or implemented actions associated with an intersection of the track T in a vehicle V, pedestrian passageway, or roadway R. In such an embodiment, a train TR would be traversing the track T and intersect the roadway R, where these vehicles V and/or pedestrians are traversing. Accordingly, in such an embodiment, it is the adjustment associated with one of the upcoming features (i.e., safety equipment, safety devices, arrangements, implemented actions, etc.) that is identified for use in making train TR control decisions.

[0063] As further shown in FIG. 1 , system 10 includes a positioning system 14, as well as a database 16. The positioning system 14 and database 16 are in communication with a locomotive central system 18. Further, database 16 may include a single database, multiple linked databases, multiple communicating databases, a relational database, a searchable database, an updated database, etc.

[0064] A positioning system 14 is operable to provide an estimated train position 20 (e.g., a calculated position of the train in the track network). For example, a positioning system 14 may use tachometer data, radio communication, and wayside signal data in determining the position of the train TR in the track network.

[0065] Database 16 includes track data 22 (e.g., geographic location of the track network TN, relative position of the track T in the track network TN, crossing grade data 24 (e.g., crossing information, crossing warning times, data associated with the track, a geographic location of an upcoming crossing grade, relative positioning of an upcoming crossing grade, status data, condition data, fault data, activity data, equipment state data, safety device data, trackside device data, detector data, switch data, crossing warning data, status indication device data, etc.). For example, track data 22 (e.g. track data including crossing grade data 24) are communicated or otherwise transmitted to the central system 18.

[0066] The data driven processes highlight data collection for pinpointing track times, median and average directions, and crossing grade activity to obtain as much data and information as possible to assist in safely and effectively managing trains operating in a complex track network. Accordingly, accuracy of data associated with the track layout and the trains operating thereon is an important aspect, especially in train control systems.

[0067] Track layout (in the x-, y-, and z-directions) must be established so that the train operator, as well as the central control system (e.g., central dispatch), understands the track direction and contour. In addition, the general position of certain features (e.g., crossings, sidings, etc.) are obtained and/or updated. According to some non-limiting embodiments, a track is divided into segments (e.g., blocks) where each individual segment is managed and controlled so multiple trains operating on a length of track in the track network are operated in a safe and effective manner. Various methods for establishing an initial track layout include a global positioning system (GPS), a geographic information system (GIS), survey techniques, and/or the like.

[0068] A crossing grade data 24 is populated before the train is on the track or dynamically in the database 16 while the train TR is traversing the track T in the track network TN. For example, while the operator is controlling the train TR, important crossing grade data 24 is already populated in the database 16 for each associated crossing before the train is within a crossing distance. This permits the central system 18 to inform the operator and/or make appropriate train control decisions based upon current and accurate information regarding an upcoming crossing grade 12 on track T. As database 16 may be updated incrementally, changes are tested and updated as new information about a crossing becomes known. For example, the process may include: (1) the central system 18 sending transmissions and gathering responsive crossing grade data 24; (2) the central system 18 or database 16 receiving crossing grade data 24 (whether in a wireless form or over the rails of the track T); and/or (3) the central system 18 or database 16 receiving crossing grade data 24 in the form of communications or data transmissions from third parties and/or remotely-located systems, etc.

[0069] Central system 18 obtains an estimated train position 20 on at least one track T from positioning system 14. For the at least one track T, central system 18 then identifies one or more upcoming features based at least in part upon the track data 22 in the database 16. For example, a train operation has access to important information regarding an approach to an upcoming feature (e.g., crossing grade 12 and/or the like) prior to encountering the upcoming feature. An upcoming feature (e.g., safety equipment, trackside equipment, a safety device, a detector, a wayside device, a status indication device, a track network crossing, a switch, a signal, a specified portion (or block) of the track, etc.). Accordingly, an upcoming crossing grade 12 is associated with a portion of the track T. Based on an upcoming crossing grade 12, an adjustment is identified for crossing grade data 24 in the track database 16. According to some non-limiting embodiments, the crossing grade data 24 is dependent upon the nature of an approach to an upcoming crossing grade 12.

[0070] Referring now to FIG. 2, FIG. 2 is a diagram of a non-limiting embodiment of a system 10 for controlling a train. As shown in FIG. 2, a positioning system 14 is configured to provide an estimated train location (e.g., position of the train). According to some non-limiting embodiments, the positioning system 14, database 16, and central system 18 are located on the train TR in the form of an integrated on-board control system 28. Accordingly, the on-board control system 28 includes the necessary components, logic, and/or software to implement the methods of the present invention, as well as to engage in various train control functions and/or activities. Through the use of an augmented GPS, more accurate location information is gathered. Use of GPS also mitigates the significant cost of deploying in-track transponders on track networks nationwide.

[0071] Approach circuits are defined by physical track circuits designed to activate preemption and warning cycles when a train occupies or shunts those circuits. An approach circuit, leading up to the crossing, may be hundreds or thousands of feet on either side of the crossing (e.g., positioned outward of the island with respect to the highway). [0072] In addition, crossing warnings may be equipped with components that activate the crossing due to train motion in the approach based on an estimated speed, distance, or arrival time at a crossing of a train detected within the approach. The crossing warning may activate when the train enters the approach as soon as the approach is occupied. For example, crossing warnings may be activated based on train occupancy within a given distance of a crossing without respect to relative speed or arrival time of a train at a crossing. As another example, track circuits may activate a crossing warning when a motion is detected within an approach. For example, a measured or determined motion indicates a train will arrive at a given crossing grade in a prescribed amount of time (e.g., 30 seconds).

[0073] In some cases, a control point is defined as interlocking when a signal and switch are logically tied together. A control point activation boundary is the maximum amount of time allowed ahead of the critical point for the locomotive to query and receive a remote crossing wayside interface device (xWIU) status message.

[0074] An integrated on-board control system 28 includes a train control unit (TCU), tachometer, GPS, transponder reader, and a cab display unit (CDU) operator display. The on-board control system 28 receives information about movement authorities, temporary speed restrictions, information about mandatory directives, and other data such as train length and train consist data given to the train by the dispatcher (via the office segment and communications segment). The on-board control system also includes an interface with locomotive control equipment (e.g., brakes, horn interface).

[0075] In some non-limiting embodiments, proximity to an approach is determined based on data transmitted from remote crossing wayside interface device30 in the wayside segment, which is positioned at or near the upcoming crossing grade 12. A wayside segment includes existing train control equipment (e.g., interlocking controllers, signal controllers, switch circuit controllers, track circuits, track/route hazard detectors, train defect detectors, and other field devices and/or the like) and wayside transmitter units used to monitor and report signal status.

[0076] As shown in FIG. 2, crossing grade data 24 may be transmitted wirelessly from a remote crossing wayside interface device 30 to a communication module 32 positioned on the train TR and integrated with the on-board control system 28. Further, and as shown in FIG. 2, crossing grade data 24 may be transmitted from an upcoming crossing grade 12 (e.g., communication unit installed at or near the upcoming crossing grade 12) through the rails of the track T, and to train TR (e.g., on-board control system 28). In either case, whether wireless communication or transmission through the rails, the appropriate data is dynamically provided to computers 18 for making train TR control systems.

[0077] Communications unit 30 includes a messaging system and wireless network that provide for the exchange of data between the locomotive, office, and wayside segments. The communications unit 30 provides management, path selection, and traffic prioritization functions. Communication unit 30 transmits crossing grade data 24 to a central system 34, which is in communication with at least one on-board control system 28 of one or more trains operating in the track network.

[0078] As shown in FIG. 2, a central system 34 is used with a locomotive onboard control system 28. For example, central system 34 includes a computer-aided dispatching system, a train control server, and database storing information (e.g., tracks, train consists, work zones, and speed restrictions). The central system 34 issues movement authorities to locomotives based on aspect information received from train control-enabled wayside signals and switches, location information received from trains, and work status from maintenance of way vehicles and personnel. The central system 34 may provide dispatch and field functions for train control.

[0079] The central system 34 is in communication with at least one on-board control system 28 of one or more trains operating in the track network. As shown in FIG. 2, a central system 34 with a locomotive on-board control system 28 is configured to utilize information communicated between one or more vehicle systems and a remote crossing wayside device to provide consistent warning times for transportation networks (e.g., features disposed within range of track detection systems automatic initiation of a warning based on information from a track detection system, temporary speed restrictions, maintenance and reporting functions, and interfacing with the wayside segment). The central system 34 includes, servers operating structure query language (SQL) databases, office communications manager (OCM), a real-time system controller (RTC), and a manual dispatcher interface. For example, the on-board control system 28, includes the appropriate track data 22 and crossing grade data 24 prior to approaching the crossing grade 12. Therefore, the appropriate data may be automatically populated in the database 16 and accessible in determining a crossing approach. In an alternate embodiment, the crossing grade data 24 may be provided directly from the wayside to the train (e.g., the on-board control system 28) for interrogation/response communication architecture or the like.

[0080] Central system 34 transmits track data 22 and/or crossing grade data 24 to the on-board control system 28, or database 16 on the train TR. Further, the central system 34 provides track data 22 and crossing grade data 24 with the most up-to-date and accurate information for use in making manual and/or automated train control decisions. For example, to ensure proper transmission of such data the central system 34 also includes a central database 36, including an updatable listing of all track data 22 and crossing grade data 24 for all tracks T in the track network. According to some non-limiting embodiments, central system 34 may be used and designated for various portions of the track network, in which case only relevant track data 22 and crossing grade data 24 would be stored in the central database 36.

[0081] With continuing reference to FIG. 2, a wayside interface device 30

(e.g., xWIU, wayside interface unit, etc.) handles communications from the train with regard to an approaching crossing. The wayside interface device 30 communicates messages regarding the conditions (e.g., speed, track, distance, and upcoming crossing grade). For example, the wayside interface device 30 can be a wayside device (e.g., xWIU). In some non-limiting embodiments, the wayside interface device 30 includes a crossing wayside interface device that is configured to process positive train control messages and wireless activation. For example, the on-board system 28 controls a crossing activation either by enabling advanced activation, delayed activation, or enforcing approach circuit design speed. The crossing grade data 24 is provided to all appropriate trains in the track network for populating the on-board database 16. Accordingly, when a train is approaching a crossing grade 12, the train may continue (e.g., normal operation) based upon the crossing grade data 24 in the database 16. System 10 provides crossing grade management and control in the track network. In addition to central database 36, a wayside device may store or relay full or various portions of the track network and crossing grade data 24. For example, only relevant track data 22 and crossing grade data 24 would be stored in the central database 36.

[0082] The central database 36 includes a complete set of necessary track data 22 and crossing grade data 24. The most appropriate track data 22 and crossing grade data 24 is transmitted to the on-board control system 28 of the train TR. Alternatively, the crossing grade data 24 may also be provided to the central system 34 (and central database 36) (e.g., remote crossing wayside interface device, a train, an operator, an on-board control system located on the train, etc.) via a communication (e.g., radio frequency transmissions, voice communication, radio communication, input of visual determinations, rail transmissions, and/or the like).

[0083] Track data 22 and/or crossing grade data 24 may be updated on database 16. Accordingly, it is envisioned that appropriate track data 22 and/or crossing grade data 24 could be provided to the central system 34 and/or the on-board control system 28 of the train TR over a network. For example, the appropriate information and data may be provided either manually or automatically from the equipment or some remote crossing wayside interface device 30 located at the crossing grade 12 over a network (e.g., the Internet). For example, all of this data may be communicated and transmitted over various applications or web-based programs and the like, in order to ensure appropriate updating of the databases 16, 36 with this dynamic data. Any number of communication techniques may be used in order to appropriately and effectively provide data to the systems.

[0084] With continuing reference to FIG. 2, system 10 includes one or more warning devices 38 positioned on the train TR, such as part of the on-board control system 28. For example, a warning device 38 may be in communication with on-board central system 18 to provide a warning signal (e.g., message) to the train operator based upon a parameter (e.g., track data 22, crossing grade data 24, estimated train position 20, train speed data, train braking data, etc.). According to some non-limiting embodiments, a warning device 38 may take many forms and provide visual, audio, tactile, or similar alarms and messages to the operator in order to ensure appropriate train operation.

[0085] With continuing reference to FIG. 2, the system 10 may include an onboard display 42 for presenting information and data track data 22 (e.g., track data 22, crossing grade data 24, status data, condition data, fault data, activity data, equipment state data, primary safety device data, secondary safety device data, primary safety arrangement data, secondary safety arrangement data, primary implemented safety action data, secondary implemented safety action data, trackside device data, detector data, switch data, avalanche detector data, high water detector data, status indication device data, train position data, estimated train position data, train speed data, train braking data, etc.). Additionally and/or alternatively, display 42 may be integrated with the on-board control system 28, as is known in the art. [0086] Central system 18 may also engage in a variety of functions. For example, central system 18 may permit the train TR to proceed without interfering with the operator's operation of the train TR. In addition, central system 18 may provide some indication to an operator regarding conditions at a crossing grade 12, such as in the form of visual data on display 42. Safety action 46 (e.g., secondary safety arrangement, secondary safety device, etc.), the train TR may continue on its course along the track T and move through the intersection without placing any vehicles V or pedestrians at risk.

[0087] On-board control system 28 transmits a message to wayside equipment controlling a nearby crossing that indicates activation at a time-to-crossing (TTC) adjusted for the actual arrival of the track vehicle at the crossing. For example, an armed crossing may include notifying a remote crossing wayside interface device 30 of an approaching train preparing to activate a crossing (e.g., track vehicle identifier, crossing identifier, track identifier, and/or direction of travel).

[0088] Preemption may refer to an activation (e.g., signal, message, etc.) provided to the auto traffic control system via a remote crossing wayside interface device 30 indicating that a train is approaching. An actuation may be transmitted a number of seconds prior to a warning system operation. A crossing that activates first is considered the most restrictive crossing. According to some non-limiting embodiments, a crossing activating sooner is considered the most restrictive condition.

[0089] A wayside interface device 30 receives an activation controlling the crossing warning from the track vehicle (e.g., a communication of on-board equipment of the track vehicle) indicating that the TTC is within detection range. For example, wayside equipment receives an adjustment factor (e.g., approach condition adjustment factor ("ACAF"), etc.). The ACAF refers to a time in seconds that is derived from track conditions on an approach to the crossing grade. An ACAF may be stored in a track database or remote crossing wayside interface device 30 message. For example, an ACAF is used in the calculation of TTC and time-to-clear-crossing (TTCC). An ACAF value is used to adjust the activation of the crossing warning with detection of the track vehicle. Adjustment of the crossing warning prevents crossing warning devices from being activated unnecessarily.

[0090] In some non-limiting embodiments, an ACAF value provides a crossing and direction specific value determined by evaluating the crossing approach conditions or train performance data. For example, an ACAF provides an adjustment to the warning activation cycle. For example, an ACAF provides adjustment reflective of conditions on the actual track. An ACAF may refer to a time in seconds derived from a subdivision specific configuration file, and used in determining the TTC and TTCC for crossings that are armed. For example, an ACAF is crossing and direction specific. A computer 10 or central system 34 may determine an ACAF by evaluating crossing approach conditions and performance data on an approach to a crossing grade.

[0091] Crossing grades use a warning predictor that detect motion of a train toward the crossing. Warning predictors can be used to calculate the TTC to the crossing. TTC can be based on the detected motion and activate the crossing warning devices, such as lights, gates, and bells, for a specified minimum amount of time prior to train arrival at the crossing. The minimum amount of warning time (i.e., the RTTC) is often regulated or set to exceed a government regulation.

[0092] A communication module 32 may be configured to transmit plural

ACAF messages, spaced a predetermined amount of time apart, while the vehicle system 28 is approaching a crossing grade 12. In some non-limiting embodiments, a predetermined amount of time between the transmissions of crossing warning messages may be configured to occur at least twice during a timeout period of a remote crossing wayside interface device 30. For example, a length of a timeout period may be obtained from a database (e.g., an onboard database, a remote database, etc.) storing characteristics of crossings, stations, remote crossing wayside devices, timeouts (e.g., length of a timeout may be obtained from a message transmitted from the remote crossing wayside interface device 30 to the vehicle system 28, including information corresponding to a timeout period.

[0093] A remote crossing wayside interface device 30 may have a timeout period of 20 seconds. For example, if 20 seconds elapse without receipt of an adjustment request message with a TTC (while information from the system 10 indicates the appropriateness of performing a crossing warning activity, such as lowering a gate), a remote crossing wayside interface device 30 will initiate a crossing warning activity. According to some non-limiting embodiments, after a communication module 32 transmits a crossing warning activation request to a remote crossing wayside interface device 30, a remote crossing wayside interface device 30 may transmit an acknowledgement of a request to the communication module 32. An acknowledgement message may include information describing the length of the timeout period (e.g., 30 seconds). For example, the communication module determines an interval at which to send repeated requests. According to some non-limiting embodiments, at least two request messages are sent within each timeout period of 30 seconds and used to determine a predetermined interval for sending request messages (e.g., 10 seconds) and transmitting TTC messages (so long as adjustment of the crossing warning is called for by the processing unit 28) every 10 seconds (or less). In other embodiments, other timeout periods or intervals may be employed.

[0094] Communication module 32 may be configured to transmit a release request to a remote crossing wayside interface device 30. For example, on-board control system 28 may determine a train is arriving before a TTC. In an example, communication module 32 may transmit a release request to a remote crossing wayside interface device 30. As another example, a communication module 32 may transmit a release request pursuant to a manual input from an operator.

[0095] Communication module 32 may be configured to (e.g., receive messages, transmit messages, pre-process information or data received in a message, format information or data to form a message, decode a message, decrypt or encrypt a message, compile information to form a message, extract information from a message, and/or the like). For example, communication module 32 may be configured to use information from a central system 34 to construct a message 48. In some non-limiting embodiments, one or more of a TTC/adjustment request, release request, track identification information, or the like may be formatted into a message along with other message portions, such as a header, address, additional information, and/or the like. In an example, one or more requests or types of information may be sent together as one message, or as parts of separate messages. The message may include a header, address, or the like that identifies a particular vehicle, direction of the train, particular crossing, and/or particular track upon which the vehicle is traveling.

[0096] Communication module 32 may be configured to transmit track or route identification information to the remote crossing wayside interface device 30. For example, in some areas, a transportation network may include multiple adjacent routes or separate tracks, such that vehicle systems may travel generally parallel to each other. For example, multiple adjacent routes may each cross a second route at the same crossing grade 12. In some non-limiting embodiments, a given remote crossing wayside interface device 30 and/or crossing warning 44 (e.g., a crossing signal, a crossing gate, a crossing sound, a crossing light, a crossing alarm, etc.) are configured to handle a crossing warning based on traffic along multiple sub-routes. Track identification information may be utilized by such a remote crossing wayside interface unit 30 to ensure that automatic closure activities are controlled for a particular track upon which a vehicle sending adjustment information is disposed.

[0097] An on-board control system 28 in the illustrated embodiment is configured to control operation of the train in accordance with information provided by the remote crossing wayside interface device 30 (e.g., information contained in the message 48). An on-board control system 28 in various embodiments is configured to enforce a speed associated with the train in the approach to reach the crossing grade at an adjusted time. For example, an on-board control system 28 may override any input from the train operator corresponding to changes in speed to reach the crossing earlier than the TTC. As one example, the permitted arrival time may be displayed to the operator on a display 42 of the on-board control system 28. As another example, a visible speed limit to follow may be displayed to the operator. In some non-limiting embodiments, the train receives a permitted arrival time at the crossing grade 12, and enforces speed limits to reach the crossing at that time. An on-board control system 28 may obtain a permitted arrival time at the crossing grade 12 and enforce a speed limit or otherwise control the speed of the train along the approach to the crossing grade 12 so that the train arrives at the crossing grade 12 at the appropriate time.

[0098] Referring now to FIG. 3, FIG. 3 is a diagram of a non-limiting embodiment of a transportation network 100 formed in accordance with a crossing grade. In some non-limiting embodiments, the transportation network 100 is configured to use information communicated between one or more on-board control systems, a central system 34, and a remote crossing wayside interface device 30 to provide consistent warning times for transportation networks within range of track detection systems. For example, the transportation network 100 uses automatic initiation of a warning based on previous route information about a track detection system or circuit when appropriate. For example, the transportation network 100 includes a first route R that includes generally parallel tracks Ti and T₂. In some non- limiting embodiments, a pair of tracks are provided for travel by a track vehicle, as shown. As an example, a first train TRi traverses the track Ti in a direction Di, and a second train TR2 traverses the track T2 in a direction D₂. The trains TRi and TR2 may each be configured as, for example, a train consist or another vehicle capable of self- propulsion on the tracks Ti and T₂. The transportation network 100 further includes a remote crossing wayside interface device 30 configured to operate the crossing warning 44.

[0099] According to some non-limiting embodiments, the network 100 also includes an island 104 interposed between approaches 102, 106. The island 104 corresponds to an area for which the crossing warning 44 are configured to be closed whenever a vehicle is present along the first route R, regardless of whether the vehicle is moving or whether a crossing warning system is adjusted. The approaches 102, 106 define areas within the range of a track detection system utilized by the remote crossing wayside interface device 30.

[00100] In some non-limiting embodiments, the remote crossing wayside interface device 30 determines when to activate (or de-activate) a warning. For example, the remote crossing wayside interface device 30 may operate the crossing warning 44 responsive to information received from a vehicle (e.g., train TRi) and/or responsive to information received from a central system 34.

[00101] With continuing reference to FIG. 3, a train using an ACAF and track identification information will now be discussed in connection with FIG. 3. According to some non-limiting embodiments, a train TRi may be traveling toward the crossing grade 12 along the track Ti of the route R. The train TRi may be outside of the approach 102 and, therefore, beyond the range of the automatic closure module of the remote crossing wayside interface device 30. In another example, the train TR2 may be traveling toward the crossing grade 12 along the track T2 of the route R. The train TR2 may be outside of the approach 106 and also beyond the range of the automatic closure module of the remote crossing wayside interface device 30. In the example scenario, the train TRi is approaching a crossing grade 12.

[00102] With continuing reference to FIG. 3, when the train TRi nears the crossing, it sends a message, such as an activation message, to a remote crossing wayside interface device 30. The message includes a crossing grade message indicating the TTC and that the train TRi is traveling on the track Ti. The TTC communicates the time of arrival at the crossing for the train TRi. In the case of the train TR2 traveling toward the crossing grade 12 along the track T2 of the route R, train TR2 sends an activation message to the remote crossing wayside interface device 30. The train TR2 is outside of the approach 106 and also beyond the range of the automatic closure module of the remote crossing wayside interface device 30. According to an embodiment, the train TRi is adjusting with a value to slow the crossing warning activation. The remote crossing wayside interface device 30 is configured to use the reported TTC from a track detection system corresponding to the travel of the train TRi to the crossing grade 12 in accordance with the message from the train.

[00103] In some non-limiting embodiments, a message is sent, such as an activation message including TTC, RTTC, and track identification information identifying track Ti as the sub-route upon which train TRi is traveling. For example, the track identification information may be obtained by the train TRi using one or more of manually input information, information from switches the train TRi has passed over, or location determination systems utilizing GPS, RFID tags, or the like. The train TRi may also utilize an on-board database describing or depicting the layout of the transportation network 100 or one or more portions thereof. The remote crossing wayside interface unit 30 is configured to use track identification information for activation of the crossing warning 44 only for track Ti, and not for other tracks or other routes. Thus, if a different vehicle, such as train TR2, approaches on a different track, the crossing warning 44 may be activated as appropriate based on the other vehicle's (e.g., TR2, etc.) position.

[00104] In some non-limiting embodiments, crossing warning 44 is activated

(e.g., lowered) responsive to the presence of the train TR2 passing through the approach 106 and/or island 104 when the train TRi is ready to approach. In such an example, the train TRi may transmit an ACAF request to the remote crossing wayside interface device 30 while the crossing warning 44 are already activated. In various embodiments, if the remote crossing wayside interface device 30 receives a request while the crossing warning 44 are already lowered, the remote crossing wayside interface device 30 may maintain the crossing warning 44 in an activated (e.g., lowered) condition and transmit an acknowledgement message to the train TRi, including information indicating that an immediate approach is permissible and communicating approach information.

[00105] In some non-limiting embodiments, a warning time at the crossing grade increases with slower train movements. According to a non-limiting embodiment in Eq.(l) below, illustrating relationships between time, distance (d), and speed or rate (r), for the fastest train operating on the track at a speed of rf, the approach must extend from the crossing at least a distance of df to provide a minimum warning time (MWT). The current speed is defined as speed parameter that represents the present speed of the train as indicated by the wheel tachometer or other methods known to one of ordinary skill in the art.

[00106] This equation is used to explain the concept of highway crossing grade warning time and train detection:

df = r_f x MWT Eq. (1)

Where df = approach circuit distance of the fastest train operating on the track, rf = fastest allowable train speed for the track in question, and MWT = minimum warning time provided to crossing users. For example, warning time may refer to a time from a crossing warning system activation until a train reaches the street.

[00107] In some non-limiting embodiments, RTTC may refer to a calculated time, based upon a warning time in force. For example, TTC may refer to a predicted TTC, and when it is different (e.g., greater than, lesser than, etc.) a predetermined time, adjustments are necessary. The maximum crossing warning time may refer to a summation of preemption and warning time. It is also used to design a location of approach circuits for a crossing.

[00108] In some non-limiting embodiments, time-at-approach may refer to the time of day that the worst case location of the front of the train will arrive at the near side approach circuit. The time-at-crossing may refer to the time of arrival (adjusted for acceleration and time uncertainty) for the furthest location of the front of the train from the crossing, where it will arrive at the near side island circuit. Time crossing clear may refer to the time of day that the furthest location of the rear of the locomotive will clear the far side island circuit. Time at stop may refer to the time of day when the wheel tachometer drops below a threshold mph (e.g., 0.5 mph) and the train is considered stopped. Time target may refer to a target where the enforcement for advisory, warning, and braking is dependent on arriving at a location based on time of day or a time to location rather than speed. Approach length time may refer to the time it takes to traverse the distance from the nearside approach circuit to the nearside island circuit traveling at the approach design speed (approach length divided by design speed).

[00109] In some non-limiting embodiments, approach max crossing time may refer to the time calculated by dividing the approach length in feet by the design speed in feet/second. The resulting time factors include any additional buffers, equipment response times, and/or the like that have been added to the max crossing time in order to design the beginning location of the approach circuit. According to some non- limiting embodiments, the activation priority flag may refer to an indication of whether PTC is the primary activation mechanism for the crossing. Advanced activation refers to a start of operation for traffic a signal preemption and/or crossing warning system devices prior to reaching the approach circuit limits.

[00110] In some non-limiting embodiments, a critical point may refer to a location where the on-board control system 28 must determine that the path ahead is clear. According to some non-limiting embodiments, if the path is not clear by the time the train reaches the critical point, a wireless activation session is not initiated. According to some non-limiting embodiments, the critical point refers to a time (e.g., N seconds) a train is ahead of the time-at-approach or below the circuit design speed. For example, a train is at a critical point if the train is traveling at or below the circuit design speed or ahead (e.g., N seconds) of the high speed communication point if the train is traveling above the circuit design speed.

[00111] In some non-limiting embodiments, on-board control system 28 may predict when the train will arrive at the grade crossing, based on position and speed calculations, providing approximately a preselected warning TTC. For example, the length of approach is tied to the track circuits on approach to the crossing. Also, the extent of a circuit is still based on the fastest train. In some non-limiting embodiments, the design time refers to the time it takes for a train traveling at the speed limit calculated for the entire length of the approach. For example, the length is a fixed number based on where the circuits are designed. For example, the minimum warning is based on a train that is traveling according to the design speed limits over the entire approach. According to some non-limiting embodiments, length, design speed, and minimum warning time are tied together.

[00112] In some non-limiting embodiments, when a slower train enters the track circuit, the crossing grade warning system may not immediately activate because a TTC for the train is not within a warning time. For example, on-board control system 28 may delay de-energizing the relay that starts the grade crossing warning devices until the slower train is at the point where the warning devices must be activated to provide the same constant warning time for the higher speed train. In an example, a minimum warning time (MWT) for all trains operating slower than a fastest allowable train would be specified in the on-board control system 28.

[00113] In some non-limiting embodiments as shown, as a train, (e.g., track vehicle) train TRi enters into the range of the approach 104, the control system will predict when the train will arrive at the grade crossing. For example, the prediction is based on position and speed calculations. For example, if train TRi is approaching the crossing grade at a speed 70 mph and if the train TRi travels at the constant speed of 70 mph through the entire approach to the crossing grade, and a minimum warning time provided to crossing users is predetermined (e.g., 30 seconds, etc.), then 30 seconds of warning time will be provided to crossing users at the highway crossing. For example, if train TRi approaches the crossing grade at a speed of 5 mph and if the train travels at the constant speed of 5 mph through the entire approach to the crossing grade, then 30 seconds of warning time will be provided to crossing users at the highway crossing when the predetermined minimum warning time is 30 seconds. For example, if the train was originally traveling at 65 mph and then accelerates to 100 mph after activating the highway grade crossing warning devices, the warning time provided to crossing users will be less than the prescribed MWT of 30 seconds.

[00114] In some non-limiting embodiments, for the approach as shown in

FIG. 3, an average or design speed over an approach, is 50 mph average. For example, the train TRi may not follow a constant speed path. For example, the train TRi may approach a speed of 70 mph and end up at a speed of 30 mph, but still have an average speed of 50 mph. For example, train TRi cannot go over 50 mph for the entire approach, because it will arrive too soon. According to some non-limiting embodiments, the ACAF value is a factor used to adjust a prediction algorithm for conditions regarding the approach. For example, train TRi can initially have a high speed, then proceed to reduce the speed when the train gets closer to the crossing. In some non-limiting embodiments, train TRi can use the design speed across the whole approach because it has access to track data (e.g., measurements of approach timing, crossing timings, and/or the like) from which the ACAF values are generated.

[00115] In some non-limiting embodiments, train TRi travels on track Ti to an approach to the crossing grade with a TTC of 35 seconds. For example, as train TRi travels on track Ti to the approach, the TTC is constantly changing. As an example, the TTC changes to 40 seconds as train TRi travels to an approach. According to some embodiments, the ACAF can be introduced if the TTC changes to 40 seconds as train TRi travels to an approach. For example, on-board control system 28 may add in the ACAF value such that the train remains at a TTC of 35 seconds. For example, onboard system 28 may automatically add in the ACAF value so that that the train remains at a TTC of 35 seconds. In some non-limiting embodiments, on-board control system 28 may test the TTC and an ACAF. For example, the on-board system 28 reproduces an ACAF and dependents (e.g., a threshold, a degree of compliance, and/or the like) and determine whether an ACAF satisfies the conditions associated with the adjustment data in the database.

[00116] In some non-limiting embodiments, as shown in FIG. 3, on-board control system 28 may determine a crossing grade adjustment for multiple trains approaching a crossing grade simultaneously (e.g., nearly at the same time, etc.). For example, the remote crossing wayside interface device 30 is configured to identify a train TR2 as traveling on a different track (e.g., track T₂) than train TRi on track Ti for which an ACAF request (or requests) corresponding to the train TRi have been received. For example, the remote crossing wayside interface device 30 may override or ignore the received train TRi ACAF request and instead activate the crossing warning 44 to avoid an unsafe (e.g., dangerous) situation where train TR2 may pass through a crossing grade 12 without a crossing warning 44 being activated. In some non-limiting embodiments, the remote crossing wayside interface device 30 may deactivate the warning after the train TR2 has passed beyond the approach 102 or island 104, if the train TRi is still approaching and if an appropriate adjustment request has been received from the train TR2. For example, the remote crossing wayside interface device 30 may raise one or more crossing gates if an appropriate adjustment request has been received from TR2. According to some non-limiting embodiments, as the train TRi is approaching, train TRi may send additional ACAF requests to the remote crossing wayside interface device 30 to adjust the crossing warning time. When there are multiple crossings in advance of the leading edge of the train and on the train's calculated route, and multiple crossings are associated with remote crossing wayside interface device 30 and multiple crossings are healthy and configured for wireless activation, the on-board control system 28, can set head-end only targets ensuring the train will satisfy the directive from the most restrictive criteria for the crossings located in its calculated route.

[00117] In some non-limiting embodiments, the on-board control system 28 may use an ACAF to decrease a TTC to allow for acceleration of a train as adjustment of the time of arrival by to allow the train to accelerate and still provide minimum warning time at the crossing. For example, the on-board control system 28 may obtain a value from the track database that is specific per train type or track (e.g., Ti, T₂, etc.). When the on-board control system 28 sends a crossing start request message, received a valid crossing start (e.g., acknowledgment indicating the crossing is armed), and a time-at- crossing has changed (e.g., changed by more than an allowable acceleration), and/or a train is traveling at or below the approach circuit design speed, (e.g., max crossing time will be violated, etc.), the on-board control system 28 can warn against acceleration. For example, the on-board control system 28 can warn against acceleration until the train slows to a speed that will allow max crossing time to elapse prior to reaching the crossing grade (e.g., nearside island circuit). According to some non-limiting embodiments, the on-board control system 28 may enforce a penalty if maximum crossing time will be violated. In some non-limiting embodiments, an allowable acceleration refers to an additional time that can be subtracted from a time of arrival to allow a train to accelerate and still provide a minimum warning time. In some non- limiting embodiments, on-board control system 28 provides a warning against acceleration until the train slows. For example, a train that is traveling above an approach circuit design speed can warn against acceleration until the train slows to a speed that will allow max crossing time to elapse prior to reaching the nearside island circuit or enforce a penalty if max crossing time will be violated. For example, a train that is traveling above an approach circuit design speed can that has sent a crossing start request message and received a valid crossing start acknowledgment can warn against acceleration until the train slows to a speed that will allow max crossing time to elapse prior to reaching the nearside island circuit or enforce a penalty if max crossing time will be violated.

[00118] Referring now to FIG. 4A, FIG. 4A is an illustration of non-limiting embodiment of a track database (e.g., wireless crossing table 400) for adjusting a crossing grade. For example, a track database includes track data updated with adjustment (e.g., timing, delay, etc.) fields for each segment of track, including a maximum preempt (e.g., max preempt time 402), a maximum warning (e.g., max warning time 404), an active indication for an approach condition adjustment factor (e.g., ACAF active 406), and an approach condition adjustment factor (e.g., ACAF value 408). In some non-limiting embodiments, the track database can be downloaded or otherwise shared for multiple trains. According to some non-limiting embodiments, track data is obtained (e.g., from a single train, from multiple trains, from a portion of trains in a track network, from an average of one or more trains in a track network, and/or the like). For example, crossing table 400 is used to store track data associated with the track network. Fields in the track database for operating the invention can also be tuned for the crossing warning time. In some non-limiting embodiments, collocate or relocate the track database, for example, a remote crossing wayside interface device 30 or a central system 34 could house the database.

[00119] In some non-limiting embodiments, a message-based system is used for changing an ACAF. For example, on-board system 28 may receive ACAF from a wayside interface device 30. For example, wayside interface device 30 may receive ACAF data for adjusting an associated crossing grade. For example, wayside interface device 30 may modify ACAF data (e.g., ACAF values, ACAF activations). According to some non-limiting embodiments, wayside interface device 30 may transmit ACAF data via a pre-established message. In some non-limiting embodiments, wayside interface device 30 may receive one or more updated ACAF values each time the values are changed. In some non-limiting embodiments, wayside interface device 30 may store one or more updated ACAF values each time the values are changed. In some non-limiting embodiments, a new track database may be modified with one or more updated ACAF values each time the values are changed.

[00120] In some non-limiting embodiments, a track database (e.g., wireless crossing table 400) for adjusting a crossing grade includes fields in the database used in conjunction with one another to establish an ACAF (e.g., expressed in seconds). According to some non-limiting embodiments, on-board computer 28 may determine and/or calculate an active ACAF feature. For example, on-board computer 28, may obtain an ACAF active field (e.g., ACAF active 406). For example, on-board computer 28, may determine if the ACAF feature is active (e.g., turned on for the specific crossing) based on an ACAF active field. For example, on-board control system 28, may determine an ACAF is active if an ACAF active field indicates active (e.g., ACAF active 406 is set to "0")·, the ACAF feature will be used. According to some non-limiting embodiments, an ACAF active field of a value other than "0"may not be used to protect against using incorrect ACAF values.

[00121] In some non-limiting embodiments, the system 10 determines that the

ACAF feature is turned on, it will query the ACAF fields shown in Fig. 4A to determine the adjustment factor. According to some non-limiting embodiments, the on-board system 28 adjusts the crossing grade based on the ACAF, as an example, as an adjustment when calculating the TTC.

[00122] In some non-limiting embodiments, system 10 includes a bi-directional and crossing specific ACAF (e.g., ACAF active 406 and ACAF value 408). According to some non-limiting embodiments, the values are located in the wireless crossing table for all crossings that are set up for wireless activation. In some non-limiting embodiments, the wireless crossing table is block specific and the table may store values for multiple directions in the block, such as one for northbound and one for southbound. For example, on-board computer 28 may provide crossing grade adjustments based on per track, per crossing, and per direction.

[00123] Referring now to FIG. 4B, FIG. 4B is an illustration of a non- limiting embodiment of a track database (e.g., historical information table 410) to determine an adjustment to modify a crossing grade. For example, system 10 may process historical track data from historical crossing activation time results to generate an ACAF value. In some non-limiting embodiments, historical values may be used to correct inefficient and/or inaccurate crossing grades, by minimizing a crossing warning each time a train approaches a crossing grade. As an example, without an ACAF, a majority of train crossings are not experiencing any crossing guidance except for a change in RTTC and TTC. Without crossing guidance, trains are less efficient and/or less accurate, for example, trains are more likely to arrive later than a predetermined time resulting in an excessive warning time.

[00124] In some non-limiting embodiments, track data is communicated from system 10. For example, system 10 communicates real-time crossing warning data from database stores of weekly crossing activation time results for one or more crossing grades.

[00125] In some non-limiting embodiments, system 10 receives activation time results from one or more trains or one or more crossing grades. For example, system 10 receives values for all crossing grades as a train traverses a track network. In some non-limiting embodiments, system 10 uses measurements (e.g., averaged across all trains, a subset of trains, or alternatively the median range can be used to calculate a time). In some non-limiting embodiments, measurements from historic track data may be used to correct crossing grades. For example, system 10 may use historic track data to improve accuracy and efficiency by tracking conditions associated with a crossing grade. For example, system 10 may process track data (e.g., automatically, semi-automatically, manually, etc.) for establishing an ACAF value. According to some non-limiting embodiments, initial ACAF values are provided to a lab analysis and modified to establish a set of values. System 10 may use the values to reduce differences in crossing warning times. For example, ACAF values may be tested in a lab test with a typical driver profile before the new values are entered into a new track database. The new track database will be used in a field test environment to ensure effectiveness (e.g., efficiency, accuracy, etc.). According to some non-limiting embodiments, the ACAF values can be used to monitor a change to driver behavior. In some non-limiting embodiments, track database values may be adjusted and re-tested in the field. According to some non-limiting embodiments, crossing warning times are used, (e.g. stored to the track database), only when they are at or below a threshold time (e.g., 6 seconds of the design warning time). The values can be stored as they meet the standard, together or for each crossing field as it changes.

[00126] Referring now to FIG. 5, FIG. 5 is a flowchart of a non- limiting embodiment of a process 500 for controlling a crossing warning system. In some non- limiting embodiments, one or more of the steps of process 500 are performed (e.g., completely, partially, etc.) by train Ti (e.g., one or more devices of train Ti). In some non-limiting embodiments, one or more of the steps of process 500 are performed (e.g., completely, partially, etc.) by another device or a group of devices separate from or including train Ti, such as positioning system 14, central system 18, and/or crossing wayside interface device 30 (e.g., one or more devices of positioning system 14, one or more devices of central system 18, one or more devices of crossing wayside interface device 30, and/or the like).

[00127] As shown in FIG. 5, at step 502, process 500 includes receiving track data associated with a crossing grade in geographic location. For example, train TR (e.g., an on-board processor 28), central system 18, and/or wayside interface device 30 receives track data associated with a geographic location from central system 18 and/or a database (e.g., a database associated with central system 10, a database located in central system 10, a database remote from central system 10, a database associated with train TR, a database located in train TR (e.g., map database 208, track database, etc.), a database remote from train TR, etc.). In some non-limiting embodiments, the track data includes (i) information associated with conditions in a track network approaching a crossing grade where a train may need to slow down after a warning cycle has initiated, and (ii) information associated with crossing grade activation time results. For example, track data may include crossing information, crossing warning times, data associated with the track, a geographic location of an upcoming crossing grade, relative positioning of an upcoming crossing grade, status data, condition data, fault data, activity data, equipment state data, safety device data, trackside device data, detector data, switch data, crossing warning data, status indication device data, etc. [00128] As shown in FIG. 5, at step 504, process 500 includes determining a TTC associated with a train. For example, train TR (e.g., an on-board processor 28), central system 18, and/or wayside interface device 30, as train TR approaches a crossing grade (e.g., detects the crossing grade approach), determines a TTC. For example, the train TR (e.g., an on-board control computer, a remote computer, etc.) determines a time that a leading edge of the train will arrive at the near side island circuit of the crossing grade. For example, train TR determines a TTC when train TR enters a track circuit designed to activate preemption and warning cycles when the train activates (e.g., occupies, shunts, etc.) these circuits. According to some non-limiting embodiments, the TTC is determined on a wayside interface device 30, for example, by one or more processing units and memory programmed to perform instructions for operating the crossing wayside interface device 30. Alternatively, processing takes place at a central computer for determining the TTC. Alternatively, this information can be determined by the train. The wayside also calculates the time variables associated with the train and crossing.

[00129] As shown in FIG. 5, at step 506, process 500 includes, determining an approach condition adjustment factor based on the track data associated with the crossing grade. In some non-limiting embodiments, train TR (e.g., an on-board processor 28), central system 18, and/or wayside interface device 30 determine an approach condition adjustment factor to adjust a TTC. For example, system 10 determines an ACAF including crossing approach condition data or performance data in order to modify (e.g., optimize, change, etc.) the warning activation cycle. According to some non-limiting embodiments, system 10 may automatically generate an ACAF to include approach condition data or performance data.

[00130] As shown in FIG. 5, at step 508, process 500 includes, adjusting the TTC time upon determination of an approach condition adjustment factor. In some non- limiting embodiments, system 10 adjusts the TTC based on the ACAF value (e.g., by adding an ACAF value to a value of the unadjusted TTC). For example, train TR (e.g., an on-board processor 28), central system 18, and/or wayside interface device 30 determine an adjusted TTC. For example, on-board system 28 may determine positional information and acceleration data from the position system, central system, wayside interface device, and/or on-board control system 28 to calculate time-at- approach and TTC, as described above. The time-at-approach is based on the expected time for the leading edge of the train to reach the nearside approach and TTC, with the adjustment for the armed ACAF. In some non-limiting embodiments, the on-board display 42 of the on-board control system 28 can display a TTC with the ACAF added to the initial value. According to some non-limiting embodiments, before determining an adjusted TTC, the wayside interface device 30 obtains the ACAF value if it exists. For example, the on-board control system 28 determines the ACAF using track and direction of the train for a crossing grade. As an example, on-board control system 28 uses this information in association with a database to determine if an ACAF value is set for a crossing approach. The on-board system 28 may determine an ACAF indicator for the particular direction and crossing.

[00131] As shown in FIG. 5, at step 510, process 500 includes, providing a crossing warning including the ACAF to the crossing grade. For example, train TR (e.g., an on-board processor 28), central system 18, and/or wayside interface device 30 send a remote crossing wayside interface device 30 a crossing activation message. According to some non-limiting embodiments, when the wayside interface device 30 receives the crossing activation message, a crossing start time is configured to adjust activation of a crossing warning system operated by a remote crossing wayside interface device 30 based on the ACAF. In some non-limiting embodiments, a crossing start request may include identification information and be configured to adjust activation of a crossing warning system for a particular vehicle traveling on a specified track, as described and shown in FIG. 3. For example, the remote crossing wayside interface device 30is configured to use information from the track detection system to operate a crossing warning system.

[00132] As shown in FIG. 5, at step 512, process 500 includes, controlling a crossing grade to delay a crossing arrival time. For example, train TR(e.g., an on-board processor 28), central system 18, and/or wayside interface device 30 controls a crossing grade in response to receiving a crossing activation in a crossing warning system. For example, the crossing grade is activated by the remote crossing wayside interface device 30 responsive to receiving a crossing activation from on-board control system 28. According to some non-limiting embodiments, a train TR is controlled in association with a crossing grade to effect arrival at the crossing grade 12 at an predetermined (e.g., established, etc.) time by the operator, the on-board control system 28, the central system 34, or a combination thereof. For example, a train TR is controlled (e.g., accelerated or decelerated) depending on whether the system has information that the arrival time is exceeding or subceeding the actual warning time and causing or risking excessive warning times at the crossing. According to some non-limiting embodiments, a time of arrival may converge on a minimum warning time. In some non-limiting embodiments, a crossing warning system may include other warnings during activation of a crossing grade, for example, one or more of sounding an alarm, providing a visual display such as flashing lights, or placing an impediment (e.g., lowering a gate) to traffic that may attempt to cross the track along a different route. According to some non-limiting embodiments, the remote crossing wayside interface device 30 operates the crossing warning system in accordance with information obtained from the track detection system. For example, the remote crossing wayside interface device 30 operates the crossing warning system in accordance with information obtained from the track detection system if no crossing start message has been received.

[00133] In some non-limiting embodiments, train TR (e.g., an on-board processor 28), central system 18, and/or wayside interface device 30 activate a crossing warning system automatically if the track detection system is an occupancy detection system and a vehicle is identified as occupying the track within the range of the track detection system.

[00134] In some non-limiting embodiments, train TR (e.g., an on-board processor 28), central system 18, and/or wayside interface device 30 displays speed control messages to the operator in accordance with the timed arrival. According to some non-limiting embodiments, controlling the crossing grade includes determining if any other vehicles other than the vehicle (i.e., train) that transmitted the request message are approaching or near the crossing. For example, the remote crossing wayside interface device 30 may receive information from the track detection system indicating that a warning activation is appropriate. For example, a remote crossing wayside interface device 30 may then determine, for example, using identification information from the crossing start message, if the information corresponds to the vehicle that sent the request or to a different vehicle. For example, if information corresponds to a different vehicle, a crossing warning system is operated by a remote crossing wayside unit 30 in accordance with the information obtained from the track detection system.

[00135] In some non-limiting embodiments, an acknowledgement and crossing timing information may be sent as portions of two or more messages. For example, train TR (e.g., an on-board processor 28), central system 18, and/or wayside interface device 30 can use the message including an acknowledgement and crossing timing information to adjust the on-board processor and parameters of the train. For example, a remote crossing wayside interface device 30 may require a vehicle approaching a crossing to continue sending periodic repeated crossing request or status messages 48. According to some non-limiting embodiments, a remote crossing wayside interface device 30 utilizes a timeout period as protection against an overly long or otherwise inappropriate adjustment of activation of a crossing warning that may be caused, for example, by a failure in communication. As a remote crossing wayside interface device 30 is associated with a request, if a valid request has been received, an adjustment factor may be activated. If a valid start request is not received within a timeout period, then a crossing warning system is operated in accordance with information obtained from the track detection system.

[00136] In some non-limiting embodiments, after an on-board control system 28 has sent a crossing start request message to an approaching crossing in advance of the leading edge of the train on the train's calculated route, a train will await a crossing start acknowledgment message from a remote crossing wayside interface device 30. After receiving a crossing start acknowledgment, an on-board control system 28, checks a message for its corresponding train address to make sure it is an expected message. For example, on-board control system 28 may determine that a crossing identifier, track, time-at-crossing, time-crossing-clear data from the crossing start request matches a crossing start acknowledgment message. For example, on-board control system 28 may provide a time target based on an acknowledged time-at-crossing from a nearside island circuit to a far-side island circuit. If a crossing identifier, track, time-at-crossing, time-crossing-clear data from the crossing start request does not match the crossing start acknowledgment, the on-board control system 28, can set a speed target based on the unhealthy speed defined in the track database for the associated crossing from the nearside island circuit to the far-side island circuit. When there is a crossing and the train has not reached the critical point, the on-board control system 28, can calculate the time-to-clear-crossing based on the expected time for the trailing edge of the train to clear the far-side island circuit adjusted for the armed approach condition adjustment factor.

[00137] In some non-limiting embodiments, train TR (e.g., an on-board processor 28), central system 18, and/or wayside interface device 30 sends a crossing start request message to an approaching crossing in advance of a leading edge of a train on a train's calculated route. According to some non-limiting embodiments, a train stops on (or ahead of) an approach circuit due to a penalty or unplanned stop and there is a crossing in advance of the leading edge of the train and the on-board control system 28 has not armed the associated remote crossing wayside interface device 30. For example, on-board control system 28 sets a head-end only time target from the nearside island circuit to the far-side island circuit based on the time-at-approach plus max crossing time plus allowable acceleration in the form of an ACAF when the train has recovered from the penalty or unplanned stop and resumed its trip.

[00138] Referring now to FIG. 6, FIG. 6 is a flowchart of a non-limiting embodiment of a process 600 for controlling a train on approach to a crossing grade. As shown in FIG. 6, at step 602, process 602 includes approaching, by a train TR, a crossing grade in advance of the leading edge of a train TR on the train's calculated route. As train TR travels at or below an approach circuit design speed, it moves closer to the crossing grade at 602. For example, train TR may continue moving without a stop because there is no station stop between the leading edge of the train and the nearside crossing island circuit.

[00139] As further shown in FIG. 6, at step 604, process 600 includes train TR moving toward a crossing grade, as train TR reaches a critical point. At 604, train TR has reached the critical point and there are no zero speed or restricted speed targets between the train's current location and the crossing grade.

[00140] As further shown in FIG. 6, at step 606, process 600 includes receiving by on-board control system 28 a crossing status indicating that the crossing is healthy and wireless activation is authorized. For example, a crossing grade is associated with a remote crossing wayside interface device 30 to send a crossing status.

[00141] As further shown in FIG. 6, at step 608, process 600 includes monitoring approach timing when a train TR moves within a specified threshold ahead of a time at approach.

[00142] As further shown in FIG. 6, at step 610, process 600 includes determining variables to communicate and an interface to activate a crossing grade. For example, a time-at-approach may be used to determine, when a crossing approach in advance of a leading edge of a train on a calculated route, and a train has not reached a critical point. According to some non-limiting embodiments, a crossing is associated with a remote crossing wayside interface device 30, an on-board control system 28, calculates the time-at-approach based on the expected time for the leading edge of the train to reach the nearside approach circuit.

[00143] As further shown in FIG. 6, at step 612, process 600 includes determining an ACAF value based on speed, position, and length.

[00144] As further shown in FIG. 6, at step 614, process 600 includes determining a TTC using an ACAF to adjust an activation, sometimes referred to as a time-at-approach. For example, on-board control system 28 determines a TTC based on a time-at-approach with the adjustment for the armed ACAF. In a further example, on-board display 42 of the on-board control system 28 may display an established TTC with the ACAF added to the initial value.

[00145] Before determining a TTC, the on-board control system 28 may determine a track and a direction of the train TR on the track T. According to some non-limiting embodiments, on-board system 28 determines if an ACAF value is set (e.g., activated) for a crossing approach in association with a database, a wayside system, etc. In some non-limiting embodiments, an on-board system 28 determines a particular direction and crossing and whether the field is populated by checking an ACAF indicator. If an ACAF is indicated (e.g., active), an ACAF value is obtained (e.g., from a track database). In an alternative embodiment, an on-board system 28 retrieves an ACAF from a database (e.g., database in the central system 34, in system 10, in wayside interface device 30, such as a wayside device). According to an embodiment, a remote messaging protocol and procedures may be used for the database call.

[00146] As further shown in FIG. 6, at step 616, process 600 includes sending a crossing start request message to a remote crossing wayside interface device 30.

[00147] As further shown in FIG. 6, at step 618, process 600 includes monitoring a train after crossing grade has been activated. For example, on-board system 28 may monitor and/or continue monitoring, at 618. For example, wayside messages are sent frequently updating the remote crossing wayside interface device 30 or the central system 10 until a train reaches the crossing.

[00148] As further shown in FIG. 6, at step 620, process 600 includes activating a crossing arm based on an ACAF. Additionally, or alternatively, system 10 passes information for deactivation of the crossing arm to the wayside interface device 30.

[00149] Referring now to FIGS. 7A-7C, FIGS. 7A-7C are diagrams of an overview of a non-limiting embodiment of an implementation 700 relating to a process for controlling a crossing grade. As shown in FIGS. 7A-7C, in some non-limiting embodiments, an implementation 700 for an early arrival warning system includes display screens for controlling a train by an onboard control system 28. In some non- limiting embodiments, another system may join or act in place of onboard control system 28, such as a central computing system, a crossing grade, and/or the like.

[00150] As shown by reference number 720 in FIG. 7A, the on-board control system 28 displays screens output to the operator of the train (e.g., on display 42). For example, the on-board control system 28 determines the time-to-next-crossing (TTNC) using three different speed profiles; current speed, estimated speed based on speed restrictions, or a theoretical speed based on an assumption of accelerating the train to a maximum authorized speed. According to some non-limiting embodiments, once an appropriate speed profile is selected a calculation is made. For example, on-board control system 28 determines if an ACAF is active for a crossing guard. In some non- limiting embodiments, if an ACAF is active, an ACAF is obtained (e.g., retrieved from a database, received from a wayside messaging system, received from a central server, and/or the like). According to some non-limiting embodiments, an active ACAF is obtained, and as an example, the ACAF is added to a time-of-arrival, (e.g., TTA). According to some non-limiting embodiments, on-board control system 28 determines a time-of-arrival at a crossing grade (e.g., a TTC, a predicted arrival time, etc.). For example, on-board control system 28 calculates a TTC by adding an ACAF to a TTA. In some non-limiting embodiments, on-board computing system 28 may determine a TTC including a later predicted arrival.

[00151] In some non-limiting embodiments, train TR (e.g., an on-board processor 28), central system 18, and/or wayside interface device 30 may determine a later predicted arrival time corresponding with a slower approach speed. For example, a later predicted arrival time corresponding with a slower approach is more likely to generate a warning for early arrival. According to some non-limiting embodiments, on-board display may provide directions (e.g., the operator will be directed to control the train to arrive at the crossing on time).

[00152] In some non-limiting embodiments, an on-board display 42 of the onboard control system 28, displays graphical information pertaining to the crossing activation. For example, on-board control system 28 may display graphical information after a train has sent a crossing start request message. For example, on-board control system 28 may display graphical information after a train has received a valid crossing start acknowledgment with a destination address matching an on-board control system's address. For example, on-board control system 28 may display graphical information showing a train traveling at or below an approach circuit design speed. According to some non-limiting embodiments, a threshold time is met, and, as an example, the on-board control system 28 sends a new crossing start request message with an updated time-at-crossing and time until the crossing clears if the previously acknowledged time-at-crossing is changed (e.g., changed by more than half of the allowable acceleration, etc.).

[00153] With continuing reference to FIG. 7A, when there is a crossing in advance of the leading edge of the train on the train's calculated route and the on-board control system 28, as in FIG. 2, has set a time target based on the acknowledged time- at-crossing to the nearside island circuit and the displayed TTC is earlier than the displayed established TTC by the allowable acceleration, the on-board control system 28, as in FIG. 2, can create a time target at the nearside island and display a warning (e.g., a yellow "EARLY ARRIVAL TIME AT CROSSING <crossing name> PREDICTED, REDUCE SPEED TO calculated speed target>MPH" advisory prompt). According to some non-limiting embodiments, the on-board display 42 of the on-board control system 28, as shown in FIG. 2, can display a warning (e.g., a yellow "WARNING" banner with the "EARLY ARRIVAL TIME AT CROSSING PREDICTED, SPEED REDUCTION TO calculated speed target>MPH" prompt).

[00154] With continuing reference to FIG. 7B, the on-board display 42 can display the RTTC in positive numbers. If the RTTC display counts down to 0, the time will go blank until the nearside island is reached and a new crossing target is created.

[00155] With continuing reference to FIG. 7C, when there is a crossing in advance of the leading edge of the train on the train's calculated route and the on-board control system 28, as in FIG. 2, has sent a crossing start request message to the remote crossing wayside interface device 30 that indicates a time target based on the acknowledged time-at-crossing to the nearside island circuit and the time-at-crossing is less than or equal to the maximum TTC allowed, The on-board display 42 of the onboard control system 28, as shown in FIG. 2, can display a TTC and a RTTC based on the acknowledged time-at-crossing. Alternatively, if the time-at-crossing is greater than the maximum TTC allowed, the on-board display 42 of the on-board control system 28, as shown in FIG. 2, can display a TTC and a display "ARMED" for the RTTC. [00156] In some non-limiting embodiments, the on-board control system 28 may activate (e.g., arm) the associated remote crossing wayside interface device 30 prior to the leading edge of the train occupying the approach circuits and the leading edge of the train stops on the approach circuits due to an unplanned stop, the train recovers and resumes its trip. After the train has recovered from the unplanned stop and the wheel tachometer is greater than a threshold speed, the on-board control system 28 can set a head-end only time target from the nearside island circuit to the far- side island circuit based on approach length times (i.e. maximum track speed, the consist's acceleration curve, and distance to the nearside island circuit, whichever is larger). Here, the Fastest Time = (Distance to crossing)/(Design Speed)+(Design Speed)/(2*Max_Acceleration) is combined with the time.

[00157] In another aspect of the invention, the on-board control system 28, as in

FIG. 2, will also acquire the TTCC when the train has not reached the critical point for a crossing and the associated remote crossing wayside interface device 30. The onboard can calculate a TTCC based on the expected time for the trailing edge of the train to clear the far-side island circuit. In addition, an ACAF is used to adjust for actual conditions.

[00158] In some non-limiting embodiments, a train should not travel on an approach to crossing at a speed where the train approaches with a TTC below a minimum warning time. In some non-limiting embodiments, the system 10 prevents a train from arriving too soon (e.g., below a minimum warning time) by changing the allowed speed at the crossing causing the train to slow down in order to meet the speed limits.

[00159] Although the invention has been described in detail for the purpose of illustration based on what is currently considered to be the most practical and preferred embodiments, it is to be understood that such detail is solely for that purpose and that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover modifications and equivalent arrangements that are within the spirit and scope of the appended claims. For example, it is to be understood that the present invention contemplates that, to the extent possible, one or more features of any embodiment can be combined with one or more features of any other embodiment.

Claims

THE INVENTION CLAIMED IS:

1. A computer-implemented method for providing constant warning times at a crossing grade, the method comprising:

receiving, with a computer system including one or more processors, track data associated with a crossing warning at the crossing grade in a geographic location;

determining, with the computer system, a time-to-crossing associated with a train;

determining, with the computer system, an approach adjustment, based on the track data associated with the crossing warning at the crossing grade; and providing, with the computer system, a crossing warning, including the approach adjustment to the crossing warning,

wherein the approach adjustment controls the crossing warning to delay a crossing arrival time.

2. The method of claim 1 , further comprising:

controlling the train to reach the crossing grade at an adjusted time of arrival based on adjusting the time-to-crossing warning time upon determination of the approach adjustment.

3. The method of claim 1 , wherein adjusting the warning time further comprises:

determining the crossing warning time precedes the time-to-crossing.

4. The method of claim 1 , wherein adjusting the warning time further comprises adjusting the warning time in response to a threshold difference between a predetermined crossing warning time and the time-to-crossing.

5. The method of claim 1 , wherein determining the approach adjustment, further comprises:

determining a difference between a predicted crossing warning time and the predetermined crossing warning time.

6. The method of claim 1, wherein determining the approach adjustment further comprises determining if the approach adjustment exists for an approaching crossing.

7. The method of claim 1, wherein determining an approach adjustment further comprises determining if the approach adjustment exists for a particular direction of travel for the train approaching the crossing.

8. The method of claim 1, wherein the approach adjustment is stored ^' -board control system, a wayside device, or a central system.

9. The method of claim 1, further comprising:

displaying an adjusted arrival time on the train;

receiving, from a device associated with the crossing grade, an arrival warning; and

controlling the train to arrive at the crossing based on the arrival warning.

10. The method of claim 9, wherein displaying an adjusted arrival time further comprises displaying a visible speed limit to follow by the train.

11. The method of claim 1, wherein an on-board system enforces speed limits to reach the crossing at an adjusted time.

12. A crossing warning adjustment system for providing constant warning times at a crossing grade, comprising:

a wayside device coupled to a crossing warning device, the crossing warning device providing a warning based on a trains approach to a crossing grade, the wayside device configured to control the warning device based on crossing requests from an approaching train; and

an on-board train system, including one or more processors, configured to communicate a crossing warning activation to the wayside device based on track data associated with an approach adjustment to the crossing warning device, the on-board locomotive further configured to:

(a) receive the track data associated with an approaching crossing grade in a geographic location;

(b) determine a time-to-crossing associated with the approaching crossing grade;

(c) determine an approach adjustment, based on the track data associated with the crossing grade; and

(d) provide a crossing warning including the approach adjustment to the crossing warning,

wherein the approach adjustment controls the crossing warning of the crossing grade to delay a crossing arrival time.

13. The crossing warning adjustment system of claim 12, wherein the transmitter is further configured to request a delay of a crossing warning activity at the crossing otherwise called for by information from a track detection system, the delay based on a difference between a predicted crossing warning time and a predetermined crossing warning time with an approach adjustment when the predetermined time precedes the crossing warning time.

14. The crossing warning adjustment system of claim 12, further comprising:

a positioning system configured to determine an estimated train position on a track within a track network and approaching the upcoming crossing grade; and at least one track information data source, which comprises at least one of the following: status data, adjustment activation data, adjustment factor data, track direction, condition data, fault data, activity data, equipment state data,

wherein the data source is located in the train and is dynamically updated while the train is traversing a track in a track network.

15. The crossing warning adjustment system of claim 12, wherein an estimated speed is comprising speed restrictions on an approach, having track information associated with at least one approach adjustment associated with a crossing warning.

16. The crossing warning adjustment system of claim 12, wherein an adjustment determination is based on location, speed, and design time of the train.

17. The crossing warning adjustment system of claim 12, wherein track information comprises at least one of track segment information and an operating condition of at least one train for at least one approach to a crossing on at least one designated route.

18. The crossing warning adjustment system of claim 12, wherein track information comprises crossing activation time results.

19. The crossing warning adjustment system of claim 12, wherein time to next crossing is determined using either current speed, design speed, estimated speed, or maximum authorized speed.

20. A crossing warning adjustment system for providing constant warning times at a crossing grade, the system comprising:

an on-board train system configured to communicate with one or more wayside devices based on an approach to a crossing grade; and

a wayside device of the one or more wayside devices, including one or more processors, coupled to a crossing warning device, the crossing warning device configured to control a trains approach to a crossing warning, the wayside device receiving crossing requests from an approaching train, and configured to:

(a) receive track data associated with the crossing warning device;

(b) determine a time-to-crossing associated with a train;

(c) determine an approach adjustment for the time-to-crossing based on the track information associated with the crossing grade; and

(d) provide a crossing warning, including the approach adjustment to the crossing warning device,