The field of invention relates generally to rail transportation and, more particularly, to identifying characteristics, such as but not limited to velocity and coupling speed, of a piece of railroad rolling stock characteristics moving within a classification yard.
Rail yards, or classification yards, are the hubs of railroad transportation systems. Therefore, rail yards perform many services, for example, freight origination, interchange and termination, locomotive storage and maintenance, assembly and inspection of new trains, servicing of trains running through the facility, inspection and maintenance of railcars, and railcar storage. The various services in a rail yard compete for resources such as personnel, equipment, and space in various facilities so that managing the entire rail yard efficiently is a complex operation.
One such service in the rail yard is assembling trains.
The hump yard process is initiated with an establishment of a list of rolling stock 8 to be humped. The list is referred to as a hump list or a cut list. Rolling stock 8 are then moved to a track, a hump lead, where they are to be coupled together to form a train. More specifically and as further illustrated in
As the piece of railroad rolling stock 8 moves along towards its intended destination, velocity of the piece of railroad rolling stock 8 is measured at discrete points by using a radar device 20. The radar device 20 measures the velocity of the piece of railroad rolling stock 8 as the piece of railroad rolling stock 8 moves toward or away from the radar 20. Velocity measurements are taken with the radar device 20 while the piece of railroad rolling stock 8 is encountering the retarders 12 and 16, and are used to achieve the desired speed when exiting the retarder 12, 16. Using the velocity measurements taken by the radar device 20 are not reliable information since the velocity of piece of railroad rolling stock is usually still in a state of flux after being affected by the retarder 12, 16. Other velocity determining devices and methods, such as but not limited to wheel detection devices, are used to determine the actual velocities when the piece of railroad rolling stock 8 in not under the influence of the retarders 12 and 16. However, such other devices have not always been reliable, such as when inclement weather is encountered.
Velocity is an important measurement because rail yards typically have established velocities for coupling piece of railroad rolling stock 8 when building a train. For example, in an exemplary embodiment, a coupling velocity may range between 4.0 to 5.0 miles per hour (6.437 to 8.047 kilometers/hour), where 4.5 miles per hour (7.24 kilometers/hour) is typically the target coupling velocity. Exceeding this range may result in damage to the piece of railroad rolling stock couplers. If below this range, the piece of railroad rolling stock 8 may not couple.
Generally, the piece of railroad piece of railroad rolling stock movement characteristics often cannot be accurately predicted due to variability in components on the piece of railroad piece of railroad rolling stock 8, age, and profile. The railroad owners and operators of classification yards in general recognize that yard management tasks would benefit from the use of management tools based on optimization principles. Towards this end, railroad owners and operators of classification yards would benefit from knowing a truer reading of the piece of railroad piece of railroad rolling stock movement characteristics so that such information may be used to accurately predict how the piece of railroad rolling stock 8 moves so that, at a minimum, coupling speeds may be more accurately predicted.
Exemplary embodiments of the invention are directed towards a system, method, and computer program for controlling movement of a piece of railroad rolling stock within a classification rail yard. The method includes determining a predicted velocity of the piece of railroad rolling stock, and collecting at least one measurement to determine a measured velocity of the piece of railroad rolling stock. A comparison of the measured velocity to the previously predicted velocity is performed, and a modification of subsequent velocity control activities due to a variation in the predicted velocity versus actual measured velocity is performed.
In another embodiment, a system for controlling movement of a piece of railroad rolling stock within a classification rail yard is disclosed. The system includes a velocity determining device configured to collect a measurement to establish velocity of the piece of railroad rolling stock at least at a specific location and as the piece of railroad rolling stock traverses an area of interest. A speed control device is also disclosed. A processor is disclosed which is configured to compare measured velocity to a predicted velocity data and to update the predicted velocity based on the measured velocity. A database is configured to provide the predicted velocity data to the processor. The processor controls the speed control device to establish a new velocity of the piece of railroad rolling stock where a minimized variation in the predicted velocity versus the measure velocity is realized.
In another embodiment of a method includes predicting velocity of the piece of railroad rolling stock before the piece of railroad rolling stock reaches a specific location is disclosed. Another step involves detecting a presence of the piece of railroad rolling stock at the specific location. Other steps include calculating velocity of the piece of railroad rolling stock at the specific location, and comparing the predicted velocity with the calculated velocity. Yet another step involves determining a correction factor for the predicted velocity based on a difference between predicted velocity and the calculated velocity. Establishing a velocity for the piece of railroad rolling stock with use of an updated predicted velocity established with the correction factor is further disclosed.
A computer software code for controlling movement of a piece of railroad rolling stock within a classification rail yard is further disclosed. The computer software code, which operates within a processor and is storable on a computer readable media, has a computer software module for predicting velocity of the piece of railroad rolling stock before the piece of railroad rolling stock reaches a specific location. A computer software module for detecting a presence of the piece of railroad rolling stock at the specific location is disclosed. A computer software module for calculating velocity of the piece of railroad rolling stock at the specific location is also disclosed. Also disclosed is a computer software module for comparing the predicted velocity with the calculated velocity. A computer software module for determining a correction factor for the predicted velocity by subtracting predicted velocity from the calculated velocity is further disclosed. Further disclosed is a computer software module for establishing a velocity for the piece of railroad rolling stock with use of an updated predicted velocity established with the correction factor.
Another computer software code for controlling movement of a piece of railroad rolling stock within a classification rail yard is also disclosed. This computer software code may be maintained on a computer readable media and operate within a processor. The computer software code includes a computer software module for determining a predicted velocity of the piece of railroad rolling stock. A computer software module for collecting at least one measurement to determine a velocity of the piece of railroad rolling stock is disclosed. Also disclosed is a computer software module for comparing the measured velocity to the previously predicted velocity. A computer software module for modifying subsequent velocity control activities to minimize a variation in the predicted velocity versus the measured velocity is further disclosed.
A more particular description of exemplary embodiments of the invention briefly described above will be rendered by reference to specific embodiments thereof that are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:
Reference will now be made in detail to the embodiments consistent with exemplary examples of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numerals used throughout the drawings refer to the same or like parts.
Exemplary embodiments of the invention solves the problems in the art by providing a system, method, and computer implemented method, such as a computer software code, for improving control of car movement resulting in an improved control of coupling speed. Persons skilled in the art will recognize that an apparatus, such as a data processing system, including a CPU, memory, I/O, program storage, a connecting bus, and other appropriate components, could be programmed or otherwise designed to facilitate the practice of the method of the invention. Such a system would include appropriate program means for executing the method of the invention.
Also, an article of manufacture, such as a pre-recorded disk, a computer readable media, or other similar computer program product, for use with a data processing system, could include a storage medium and program means recorded thereon for directing the data processing system to facilitate the practice of the method of the invention. Such apparatus and articles of manufacture also fall within the spirit and scope of the invention.
Broadly speaking, a technical effect is determining and/or controlling a performance of a rail car. Though performance is associated with velocity herein, those skilled in the art will readily recognize that performance may be associated to other aspects of a rail car than just its velocity.
To facilitate an understanding of the exemplary embodiments, embodiments are described hereinafter with reference to specific implementations thereof. Exemplary embodiments may be described in the general context of computer-executable instructions, such as program modules, being executed by a device, such as but not limited to a computer, designed to accept data, perform prescribed mathematical and/or logical operations usually at high speed, where results of such operations may or may not be displayed. Generally, program modules include routines, programs, objects, components, data structures, etc. that performs particular tasks or implement particular abstract data types. For example, the software programs that underlie exemplary embodiments of the invention can be coded in different programming languages, for use with different platforms. It will be appreciated, however, that the principles that underlie exemplary embodiments of the invention can be implemented with other types of computer software technologies as well.
Moreover, those skilled in the art will appreciate that exemplary embodiments of the invention may be practiced with other computer system configurations, including multiprocessor systems, microprocessor-based or programmable consumer electronics, minicomputers, mainframe computers, and the like. Exemplary embodiments of the invention may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote computer storage media including memory storage devices.
Furthermore, even though hump yards are primarily discussed herein the exemplary embodiments discussed may also work with any type of rail classification yards. Therefore, any reference to hump yards shall not be considered limiting with respect to the use of exemplary embodiments of the invention in other rail classification yards.
Referring now to the drawings, embodiments of the present invention will be described. Exemplary embodiments of the invention can be implemented in numerous ways, including as a system (including a computer processing system), a method (including a computerized method), an apparatus, a computer readable medium, a computer program product, or a data structure tangibly fixed in a computer readable memory. Several embodiments of the invention are discussed below.
A speed control device 23, such as but not limited to a retarder 12, 16 is provided. A processor 70 is configured to compare the measured velocity data with a predicted velocity data and to update the predicted velocity based on the actual measured velocity. A database 72 is further disclosed. The database 72 is configured to provide the predicted velocity data to the processor. The processor 70 controls the speed control device 23 to establish a new velocity of the piece of railroad rolling stock 8 based on the updated predicted velocity.
An energy algorithm 75, embodied in computer-executable instructions stored within a computer-readable memory which may be loaded and executed by the processor 70, is disclosed. The energy algorithm 75 functions within the processor 70 for controlling the velocity of the piece of railroad rolling stock 8 as the piece of railroad rolling stock leaves the speed control device 23. Calculations and/or factors with the energy algorithm 75 are adjusted based on the updated predicted velocity.
A second algorithm 80 is also provided for operating within the processor 70. As with the energy algorithm 75, the second algorithm 80 is embodied in computer-executable instructions stored within a computer-readable memory which may be loaded and executed by the processor 70. The second algorithm 80 is the element that performs the actual comparison of the measured velocity to the predicted velocity data and updates the predicted velocity based on the actual measured velocity. As disclosed above, the predicted velocity data may be located in a database 72 wherein information in the database 72 is updated. Therefore based on the measured velocity a new predicted velocity is determined for the piece of rolling stock 8 as it continues through the classification yard.
Since the wheels of the piece of railroad rolling stock 8 are rolling over the track 25, depending on the quality of the wheels and track surface, surface resistance qualities are likely to vary. Varied resistance qualities may also be affected by environmental conditions. A filtering device 81 is further disclosed. The filtering device 81 is used to remove extraneous measured velocity caused, but not limited to, at least one of wheel condition, track condition, and erratic movement of the piece of railroad rolling stock 8. The filtering device 81 may be an algorithm within the processor 70, or more specifically is embodied in computer-executable instructions stored within a computer-readable memory which may be loaded and executed by the processor 70. Though three different algorithms are illustrated, those skilled in the art will readily recognize that a single algorithm may perform the function of the three algorithms disclosed herein. Furthermore, though only one processor is disclosed, a plurality of processors may be utilized where parts and/or complete algorithms function within at least one of the processors.
The impedance circuit 28 includes a feed point 35 at which a signal, such as but not limited to an alternating electrical current, is introduced to the track via an appropriate electrical source, and/or transmitter 37. The signal travels along a first rail 39 of the railroad track 25. A shunt 40 is provided at a distance away from the transmitter 37. The shunt 40 is coupled to the first rail 39 and a second rail 41 of the railroad track 25. A receiver 45 is provided, proximate the second rail 41 of the railroad track 25. The receiver 45 is attached to the second rail 41 at a connection point 36. In an exemplary embodiment the transmitter 37 and receiver 45 are aligned. More specifically, the distance between where the shunt 40 connects to the first rail 39 and the feed point 35 for transmitter 37 equals a distance between where the shunt 40 connects to the second rail 41 and the connection point 36 for the receiver 45. Therefore when the piece of railroad rolling stock 8 is not between the shunt 40 and the transmitter/receiver 37, 45 when the transmitter 37 emits a signal, a defined signal Zmax, is read, or measured, by the receiver 45. In reading the signal, the receiver 45 reads the strength of the signal.
When the signal is generated by an alternating current source, the impedance circuit 28 may be closed by an electrical connection 43 from the transmitter 37 which provides an alternating current source to the receiver 45. The length of the impedance circuit 28 may vary, but an exemplary length may be half a mile between the shunt 40 and transmitter/receiver 37, 45. With respect to the impedance circuit 28 through which an alternating current source flows, the hardware used in such a system is known to those skilled in the art and may include impedance systems incorporating crossing predictor type hardware components.
As is disclosed briefly above, a processor, or controller, 70 is also provided and is in communication with the receiver 45 to monitor the signal along the impedance circuit 28. The processor 70 is preferably a component of a classification yard monitoring system, such as but not limited to, the controller for a retarder 12, 16. The change in impedance across the impedance circuit 28 as the piece of railroad rolling stock 8 advances on the track 25 is predictable. Accordingly, before the first axle 30 of the piece of railroad rolling stock passes the transmitter/receiver 37, 45 and is within the impedance circuit 28 the processor 70 is interpreting data received from the receiver 45 as the maximum distance from feed point 35 to shunt 40.
When the piece of railroad rolling stock 8, more specifically the axle 30 of the piece of railroad rolling stock 8 closest to the transmitter/receiver 37, 45, is between the shunt 40 and the transmitter/receiver 37, 45, it takes the place of the shunt 40 in the impedance circuit 28. As the piece of railroad rolling stock 8 moves along the track 25, from the transmitter/receiver 37, 45 towards the shunt 40, the impedance of the track 25 changes based on the position of the axle 30, 31, 32, 33 closest to the transmitter/receiver 37, 45. More specifically when the front axle 30 passes the transmitter/receiver 37, 45, the impedance drops to zero and then starts to increase as the first axle 30 moves away from the transmitter/receiver 37, 45 and towards the shunt 40. As the piece of railroad rolling stock 8 progresses further, the impedance will drop to zero each time another axle 31, 32, 33 passes the transmitter/receiver 37, 45. When the last axle 33 is within the impedance circuit 28 the impedance will no longer drop to zero with respect to this particular piece of railroad rolling stock 8. In an exemplary embodiment, measuring the voltage change is the basis for detecting the impedance variation. The impedance variation (based on a percentage) and the distance variation are thus mathematically predictable. For example, mathematical predictability is possible because the impedance variation may change linearly based on the distance variation over time.
Unlike radar devices 20 and wheel detector devices 19 shown in
Since the piece of railroad rolling stock 8 is a known entity, by sampling a change in distance between the transmitter 37/receiver 45 to the shunt 40 over time, the velocity of a specific piece of railroad rolling stock 8 may be calculated. More specifically, using the distance variation and the time variation, the velocity of the piece of railroad rolling stock 8 is calculated. As the receiver 45 collects actual information from the moving piece of railroad rolling stock 8, the data is communicated to the processor 70, which in turn compares the data with data contained in the prediction calculations. In an exemplary embodiment the prediction calculations may be in the database 72 where a look-up chart or graph 73 is provided.
As disclosed above a filtering device 81 is provided. The filtering device 81 may be used to filter excursions that may result from varied surface resistance qualities, among other variations encountered, so that a smooth rate of change for the velocity of the piece of railroad rolling stock is determined. Though not limited to this embodiment, when the filtering device 81 is an algorithm measured velocity data, which is based on an actual velocity, may be extrapolated to produce a curve illustrating a smooth rate of change, where the curve is representative of the calculated velocity. The calculated velocity can be continuously compared to the actual velocity (or measured velocity) measured by a dedicated track velocity measurement circuit such as, but not limited to, the radar device 20. Towards this end, a plurality of embodiments of the invention may be used throughout a hump yard to provide a estimate, measure, calculate, and control velocity of the piece of railroad rolling stock 8 prior to the piece of railroad rolling stock before the piece of railroad rolling stock 8 reaches the impedance circuit 28 where the train that the piece of railroad rolling stock will join.
Having a plurality of estimates, which are corrected, based on actual velocity measurements, will result in improving car performance predictions, which may be specific to the track 25 and/or specific piece of railroad rolling stock 8. Therefore the measurement of velocity over time and correcting estimated earlier readings will result in discerning coupling speeds based on velocity just before the velocity changes to zero, or when the piece of railroad rolling stock 8 is coupled.
Those skilled in the art however will recognize that when a piece of railroad rolling stock 8 is initially coupled, the velocity of the piece of railroad rolling stock 8 does not immediately change to zero. Instead, the piece of railroad rolling stock 8 may jerk either forward and/or backward before coming to a complete rest. As disclosed above, the filtering device 81 may be used to filter out this additional movement at the time of coupling.
Though the configuration disclosed in
Referring to
The flowchart 50 further discloses establishing at least at one of a target coupling velocity at a time the piece of railroad rolling stock is coupled and an actual velocity at least at one of a specific location within the classification yard and as the piece of railroad rolling stock traverses an area of interest within the classification yard, at 64. At least any one of the predicted velocity, the calculated velocity, the correction factor, and/or the updated predicted velocity may be stored, such as in a database for subsequent application, at 66. As disclosed above, this flowchart 50 may be implemented using a computer software code that functions within a processor. The computer software code may be contained on a computer readable media.
While exemplary embodiment of the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes, omissions and/or additions may be made and equivalents may be substituted for elements thereof without departing from the spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. Moreover, unless specifically stated any use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another.
This application is based on and claims priority to U.S. Provisional Application No. 60/885,789 filed Jan. 19, 2007.
Number | Date | Country | |
---|---|---|---|
60885789 | Jan 2007 | US |