Embodiments of the inventive subject matter described herein relate to scheduling systems for vehicles traveling in a transportation network.
A transportation network for vehicles can include several interconnected main routes on which separate vehicles travel between locations. Some of the main line routes may be single routes, which means that only a single vehicle can travel along the single main line route in a given direction and two vehicles traveling in opposite directions cannot simultaneously travel across the same section of the single main line route. For example, rail vehicles such as trains may travel along a main line track but may be unable to simultaneously travel in opposite directions along the same section of the main line track. However, vehicles may need to travel along the same section of the main line route in an opposite direction. In order to avoid collision between the vehicles traveling in opposite directions on the same section of a single main line route, a siding section of the route may be connected with the main line route.
A siding section of the route may include section of the route that is connected with the main line route and provides an auxiliary path for one of the vehicles traveling in opposite directions on the same single main line route. For example, a first train travelling in a first direction on a main line track can pull off of the main line track onto a siding section of track while a second train travelling in an opposite second direction on the main line track can continue along the main line track and pass the first train on the siding section. This event between two vehicles traveling in opposite directions can be referred to as a “meet event” or a “meet-and-pass event.” The first vehicle can be referred to as a “yielding” vehicle and the second vehicle can be referred to as a “passing” vehicle.
The vehicles may move within the transportation network according to various schedules. The schedules may dictate times that the vehicles are expected to arrive at various locations. However, due to various anticipated or unforeseen circumstances, one or more of the vehicles may be running behind schedule. For example, trains may be behind schedule due to damaged portions of the track, unexpected delays in leaving one or more scheduled locations, and the like.
The meet events can be included in the schedules of the vehicles. If one of the vehicles that participates in a meet event is behind schedule and arrives late to the meet event, then the other vehicle in the meet event may need to stop and wait. For example, if the passing train for a meet event is behind schedule, then the yielding train may continue to the originally scheduled meet event and wait an additional time period for the late passing train to arrive and pass on the main line track. Typically, the yielding train travels at the maximum allowable speed on the main line track to the meet event. As a result, the yielding train has unnecessarily traveled to the meet event earlier than required and at a faster speed than required.
A need exists for a system and method for modifying movement plans or schedules of vehicles that reduces meet events that result in yielding vehicles traveling to the meet event too fast and/or too early due to delays in the passing vehicles.
In one embodiment, a system (e.g., an off-board scheduling system) includes a monitoring module, a congestion module, a modification module, and a communication module. The monitoring module is configured to monitor plural separate vehicles traveling in a transportation network according to a movement plan of the network. The movement plan directs the vehicles to move through the network according to schedules associated with the separate vehicles and includes an original meet event between a yielding vehicle and a passing vehicle of the separate vehicles. The congestion module is configured to calculate a throughput parameter of the network that is representative of a statistical measure of adherence to the movement plan by the separate vehicles. The modification module is configured to determine a confidence parameter representative of a probability that changing the original meet event does not reduce the throughput parameter of the network. The modification module also is configured to modify the original meet event to an updated meet event when the confidence parameter exceeds a predetermined threshold. The communication module is configured to transmit the updated meet event to one or more of the yielding vehicle or the passing vehicle as at least one of the yielding vehicle or the passing vehicle is moving toward the original meet event, for the one or more of the yielding vehicle or the passing vehicle to receive the updated meet event from the communication module and change a speed of the yielding vehicle or the passing rail vehicle to arrive at the updated meet event.
In another embodiment, a method (e.g., a method for adjusting a movement plan of a transportation network) is provided that includes monitoring plural separate vehicles traveling in the transportation network according to a movement plan of the network. The movement plan directs the vehicles to move through the network according to schedules associated with the separate vehicles. The movement plan includes an original meet event between a yielding vehicle and a passing vehicle of the separate vehicles. The method also includes determining a throughput parameter of the network that is representative of a statistical measure of adherence to the movement plan by the separate vehicles, determining a confidence parameter representative of a probability that changing at least one of an original location or an original time of the original meet event does not reduce the throughput parameter of the network, modifying at least one of the original location or the original time of the original meet event to at least one of an updated location or an updated time of an updated meet event when the confidence parameter exceeds a predetermined threshold, and transmitting at least one of the updated location or the updated time to one or more of the yielding vehicle or the passing vehicle as at least one of the yielding vehicle or the passing vehicle is moving toward the location of the original meet event.
In another embodiment, a computer readable storage medium for a system having a processor (e.g., an off-board scheduling system of a transportation network) is provided. The computer readable storage medium includes one or more sets of instructions configured to direct the processor to monitor plural separate vehicles traveling in the transportation network according to a movement plan of the network. The movement plan directs the vehicles to move through the network according to schedules associated with the separate vehicles. The movement plan includes an original meet event between a yielding vehicle and a passing vehicle of the separate vehicles. The one or more sets of instructions also are configured to direct the processor to determine a throughput parameter of the network that is representative of a statistical measure of adherence to the movement plan by the separate vehicles and determine a confidence parameter representative of a probability that changing at least one of an original location or an original time of the original meet event does not reduce the throughput parameter of the network. The one or more sets of instructions are further configured to direct the processor to modify at least one of the original location or the original time of the original meet event to at least one of an updated location or an updated time of an updated meet event when the confidence parameter exceeds a predetermined threshold and to transmit at least one of the updated location or the updated time to one or more of the yielding vehicle or the passing vehicle as at least one of the yielding vehicle or the passing vehicle is moving toward the location of the original meet event, for the one or more of the yielding vehicle or the passing vehicle to receive the at least one of the updated location or the updated time and change a speed of the yielding vehicle or the passing rail vehicle to arrive at the updated meet event.
In another embodiment, a method (e.g., a method for directing movement of vehicles in a transportation network) includes, at one of a yielding vehicle or a passing vehicle, receiving from an off-board scheduling system at least one of an updated location or an updated time of a meet event of the yielding vehicle and the passing vehicle and changing a speed of said one of the yielding vehicle or the passing vehicle in response to said at least one of the updated location or the updated time to arrive at the meet event.
In another embodiment, a system (e.g., an on-board control system of a vehicle) includes a control unit that is configured to be disposed on-board a first vehicle and to receive from an off-board scheduling system at least one of an updated location or an updated time of a meet event of the first vehicle and a second vehicle. The control unit is configured to change a speed of said first vehicle in response to said at least one of the updated location or the updated time to arrive at the meet event.
In another embodiment, a system (e.g., an on-board system of a vehicle) includes a control unit for a first vehicle and a computer readable storage medium. The computer readable storage medium has one or more sets of instructions that are configured to direct the control unit to receive at least one of an updated location or an updated time of a meet event of the first vehicle and a second vehicle from an off-board scheduling system and change a speed of the first vehicle in response to said at least one of the updated location or the updated time to arrive at the meet event.
The present inventive subject matter will be better understood from reading the following description of non-limiting embodiments, with reference to the attached drawings, wherein below:
One or more embodiments of the inventive subject matter described herein provide a scheduling system that monitors several vehicles travelling in a transportation network of a plurality of routes. The vehicles travel in the transportation network according to one or movement plans. The movement plans provide schedules for the vehicles to move through the transportation network. The movement plan includes meet events between two or more vehicles. A meet event can be a location and time at which first and second vehicles simultaneously travel toward each other in opposite directions along a common section of a route, and the first vehicle is scheduled to pass the second vehicle when the second vehicle pulls off of the common section of the route onto a siding section of the route. For example, a meet event can include a location of the transportation network that includes a main line of a rail track having a siding section of the track. During the meet event, the second vehicle moves off of the main line of the track to the siding section of the track and may stop or slow while the first vehicle continues to move along the main line and pass the second vehicle. The first vehicle that passes the second vehicle at the meet event may be referred to as the passing vehicle. The second vehicle that moves to the siding section to allow the passing vehicle to pass can be referred to as the yielding or give way vehicle.
The scheduling system can monitor a throughput parameter of the transportation network. The throughput parameter represents a statistical or quantitative measure of adherence to the movement plan by the vehicles. A relatively high throughput parameter indicates that the vehicles are traveling through the network according to the respective schedules. A relatively low throughput parameter may indicate that one or more of the vehicles are traveling through the network ahead of (e.g., arriving early at scheduled locations) or behind (e.g., arriving late at scheduled locations) the respective schedules. The scheduling system can determine a confidence parameter that represents a probability that changing a speed of one or more vehicles arriving at a meet event will not negatively impact the throughput parameter. For example, if a passing vehicle is set to arrive late to a meet event (or the yielding vehicle is set to arrive early to the meet event), the scheduling system may determine a low probability that slowing the speed of the yielding vehicle will negatively impact (e.g., reduce) the throughput parameter.
The scheduling system can modify the meet event and transmit the modified meet event to one or more of the vehicles. The vehicles may proceed toward the meet event based on the modified details. For example, the yielding vehicle may slow down to arrive at the meet event later than originally scheduled. The slowing of the yielding vehicle can increase fuel savings while avoiding increasing the congestion of the transportation network.
Plural separate vehicles 108, 110, 112 travel along the routes 104, 106. In the illustrated embodiment, the vehicles 108, 110, 112 are shown and described herein as rail vehicles or rail vehicle consists. However, one or more other embodiments may relate to vehicles other than rail vehicles or rail vehicle consists. For example, the vehicles may represent other off-highway vehicles, automobiles (e.g., cars, busses, and the like), marine vessels, airplanes, and the like. A vehicle 108, 110, 112 may include a group of powered vehicles 126 (referring to rail vehicles configured for self propulsion, e.g., locomotives) and/or non-powered vehicles 128 (referring to rail vehicles not configured for self propulsion, e.g., cargo or passenger cars) that are mechanically coupled or linked together to travel along the routes 104, 106. As shown in
The siding section route 106 is an auxiliary portion of a route that branches off of the main line route 104. The siding section route 106 may be connected to the main line route 104 and may run parallel to the main line route 104 between two or more locations where the siding section route 106 is coupled with the main line route 104. In one embodiment, the siding section route 106 may be formed from lighter materials or construction such that the siding section route 106 may have lower speed and/or weight limits than the main line route 104. The siding section route 106 may be used by the vehicles 108, 110, 112 to move off of the main line route 104 when another vehicle 108, 110, 112 is approaching. For example, the vehicle 110 may move from the main route 104 to the siding section route 106 when a second rail vehicle 112 approaches along the same main route 104. The vehicle 110 can travel, slow down, and/or stop on the siding section route 106 until the second rail vehicle 112 has passed on the main route 104. Once the second rail vehicle 112 has passed, the first rail vehicle 110 can return to the main route 104.
In one embodiment, the vehicle 108, 110, 112 that moves to the siding section route 106 is referred to as a “yielding vehicle” or a “stopping vehicle,” even though the vehicle 108, 110, 112 may not cease all movement on the siding section route 106. The vehicle 108, 110, 112 that passes on the main route 104 while the yielding vehicle 108, 110, 112 is on the siding section route 106 can be referred to as a “passing vehicle.” A “meet event” represents a location and/or time at which the passing vehicle 108, 110, 112 and the yielding vehicle 108, 110, 112 meet and pass each other. For example, a meet event can include the geographic location of the siding section route 106 and the time at which the passing vehicle 108, 110, 112 passes the geographic location of the siding section route 106.
The vehicles 108, 110, 112 travel along the routes 104, 106 according to a movement plan of the transportation network 102. The movement plan is a logical construct of the movement of the vehicles 108, 110, 112 moving through the transportation network 102. For example, the movement plane may include a schedule for each of the vehicles 108, 110, 112, with the schedules directing the vehicles 108, 110, 112 to move along the routes 104, 106 at associated times. In one embodiment, the movement plan includes a list, table, or other logical arrangement of geographic locations (e.g., Global Positioning System coordinates) within the transportation network 102 and associated times. The vehicles 108, 110, 112 move along various paths within the transportation network 102 to arrive at the geographic locations associated with the schedule of each vehicle 108, 110, 112 at the specified times. The locations in the movement plan can be referred to as “scheduled waypoints” and the times at which the vehicles 108, 110, 112 are scheduled to arrive or pass the scheduled waypoints can be referred to as “scheduled times.”
The movement plan can be based on starting locations and destination locations of the vehicles 108, 110, 112. For example, a schedule may be developed for each vehicle 108, 110, 112 that directs the vehicle 108, 110, 112 where and when to move within the transportation network 102 to arrive at a specified destination from the starting location of the vehicle 108, 110, 112. The schedules may include several scheduled waypoints located between the starting location and the destination location of the vehicle 108, 110, 112, along with scheduled times for the scheduled waypoints. For example, a schedule may include several waypoints 114 located along a route between the starting location and the destination location of a vehicle 108, 110, 112.
The movement plan may be determined by the scheduling system 100. As shown in
The vehicles 108, 110, 112 include wireless antennas 118, such as RF or cellular antennas, that receive the schedules from the scheduling system 100. The wireless antenna 118 communicates the received schedule to an energy management system 120 disposed on-board the vehicle 108, 110, 112. The energy management system 120 may be embodied in a computer, computer processor, microcontroller, microprocessor, or other logic-based device, that operates based on one or more sets of instructions (e.g., software) stored on a tangible and non-transitory computer readable storage medium (e.g., hard drive, flash drive, ROM, or RAM). The energy management system 120 may include a location determining device, such as a Global Positioning System (GPS) device, that identifies a current location of the vehicle 108, 110, 112 and a timing device, such as a clock, that determines a current time of the vehicle 108, 110, 112. The energy management system 120 can compare the current location and time of the vehicle 108, 110, 112 to the received schedule to determine if the vehicle 108, 110, 112 is ahead of schedule (e.g., is arriving at a scheduled waypoint 114 before an associated scheduled time), behind schedule (e.g., is arriving at a scheduled waypoint 114 after an associated scheduled time), or on time (e.g., is arriving at a scheduled waypoint 114 at a scheduled time or within a predetermined time period of the associated scheduled time).
Based on the comparison between the current location and time of the vehicle 108, 110, 112 and the received schedule, the energy management system 120 may generate control instructions that direct operation of a propulsion subsystem 122 of the respective vehicle 108, 110, 112. The propulsion subsystem 122 can include one or more traction motors, brakes, and the like, that provide tractive effort to propel the vehicle 108, 110, 112 along the routes 104, 106 and provide braking efforts to slow or stop movement of the vehicle 108, 110, 112. The control instructions may include commands that direct an operator of the vehicle 108, 110, 112 to change or set the tractive effort and/or braking effort supplied by the propulsion subsystem 122 of the vehicle 108, 110, 112, or commands that automatically change or set the tractive effort and/or braking effort. For example, if the vehicle 108, 110, 112 is behind schedule, the control instructions may reduce braking effort and/or increase tractive effort. If the vehicle 108, 110, 112 is ahead of schedule, the control instructions may increase braking effort and/or reduce tractive effort.
In the illustrated embodiment, the energy management system 120 determines a trip plan that dictates one or more operations of the propulsion subsystem 122 during a trip of the corresponding vehicle 108, 110, 112. A trip of the vehicle 108, 110, 112 includes the travel of the vehicle 108, 110, 112 from a starting location to a destination location. The energy management system 120 can refer to a trip profile that includes information related to the vehicle 108, 110, 112, the route or surface on which the vehicle 108, 110, 112 travels, the geography over which the route or surface extends, and other information in order to form the trip plan. The trip plan can be used to control the propulsion subsystems of different powered rail vehicles in the vehicle 108, 110, or 112 to change the tractive efforts of the propulsion subsystems as the vehicle 108, 110, 112 travels over different segments of the trip according to the trip plan.
For example, if the trip profile requires the vehicle 108, 110, or 112 to traverse a steep incline and the trip profile indicates that the vehicle 108, 110, or 112 is carrying significantly heavy cargo, then the energy management system 120 may form a trip plan that directs one or more of the powered rail vehicles of the vehicle 108, 110, or 112 to increase the tractive efforts supplied by the respective propulsion subsystems. Conversely, if the vehicle 108, 110, or 112 is carrying a smaller cargo load based on the trip profile, then the energy management system 120 may form a trip plan that directs the propulsion subsystems to increase the supplied tractive efforts by a smaller amount than the tractive efforts would otherwise be increased if the data indicated a heavier cargo load. The trip plan may be formed according to other factors, such as changes in the route that the vehicle 108, 110, or 112 travels along, regulatory requirements (e.g., emission limits) of the regions through which the vehicle 108, 110, or 112 travels, and the like, and based on the trip profile. In one embodiment, the energy management system 120 includes a software application such as the Trip Optimizer™ system provided by General Electric Company, to control propulsion operations of the vehicle 108, 110, or 112 during the trip in order to reduce fuel consumption of the powered rail vehicles and/or to reduce wear and tear on the vehicle 108, 110, 112.
The trip data used to form the trip profile may include vehicle (e.g., train) data, route data, and/or an update to trip data, vehicle data, or route data. Vehicle (e.g., train) data includes information about the vehicle and/or cargo being carried by the vehicle. For example, vehicle data may represent cargo content (such as information representative of cargo being transported by the vehicle) and/or vehicle information (such as model numbers, manufacturers, horsepower, and the like, of locomotives and/or other railcars in the vehicle). Route data may include information about an upcoming trip by the vehicle. By way of example, route data may include a trip profile of an upcoming trip of the vehicle (e.g., information that can be used to control one or more operations of the vehicle, such as tractive and/or braking efforts provided during the powered units of a vehicle during an upcoming trip), station information (such as the location of a beginning station where the upcoming trip is to begin and/or the location of an ending station where the upcoming trip is to end), restriction information (such as work zone identifications, or information on locations where the route is being repaired or is near another route being repaired and corresponding speed/throttle limitations on the vehicle), and/or operating mode information (such as speed/throttle limitations on the vehicle in various locations, slow orders, and the like). Route data can include information about the route or rails upon which the vehicle travels. For example, the route data can include information about locations of damaged sections of a route, locations of route sections that are under repair or construction, the curvature and/or grade of a route, GPS coordinates of the route, and the like. The route data is related to operations of the vehicle as the route data includes information about the route that the vehicle is or will be traveling on. However, other types of data can be recorded as the data and/or the data may be used for other operations. The term “data” may refer to trip data, vehicle (e.g., train) data, and route data, only one of trip data, vehicle data, or route data, or another type of data.
In one embodiment, the vehicle 108, 110, 112 includes a display device 124 that visually presents the control instructions to the operator on-board the vehicle 108, 110, 112. For example, a computer monitor or display screen may present textual settings for a throttle or brake setting of the propulsion subsystem 122. The textual settings prompt the operator to change the tractive effort and/or braking effort of the propulsion subsystem 122. Alternatively, the control instructions may be communicated to the propulsion subsystem 122 to automatically control the tractive effort and/or braking effort of the propulsion subsystem 122. For example, the propulsion subsystem 122 may receive an updated throttle or brake setting from the energy management system 120 and modify the tractive effort or braking effort in response thereto.
An output device 212 is communicatively coupled with the processor 200. The output device 212 presents information to an operator of the scheduling system 100, such as schedules of vehicles 108, 110, 112 (shown in
The monitoring module 204 monitors the vehicles 108, 110, 112 (shown in
The congestion module 206 determines one or more throughput parameters of the transportation network 102 (shown in
The term “statistical measure of adherence” refers to a quantity that is calculated for a vehicle 108, 110, 112 and that indicates how closely the vehicle 108, 110, 112 is following the schedule associated with the vehicle 108, 110, 112. Several statistical measures of adherence to the movement plan may be calculated for the vehicles 108, 110, 112 traveling in the transportation network 102. The throughput parameter may be based on or calculated from the statistical measures of adherence of the several vehicles 108, 110, 112.
In order to determine a statistical measure of adherence to the schedule associated with vehicles 108, 110, 112, the congestion module 206 determines if the vehicle 108, 110, 112 adheres to the schedule. A vehicle 108, 110, 112 adheres to the schedule of the vehicle 108, 110, 112 by arriving at or passing through the scheduled waypoints 114 (shown in
Alternatively or in addition to the above, the statistical measure of adherence may be based on one or more time differences between (a) the scheduled time that the vehicle 108, 110, 112 is to arrive at or pass through a scheduled waypoint 114 and (b) the actual time that the vehicle 108, 110, 112 arrives at or passes through the scheduled waypoint 114. For example, the statistical measure of adherence may be a sum of the time differences between the actual times of arrival and the scheduled times for several scheduled waypoints 114 of a vehicle 108, 110, 112. In another embodiment, another quantifiable measure may be performed to determine how closely the vehicle 108, 110, 112 is following or abiding by the schedule of the vehicle 108, 110, 112.
The first column 302 includes a list of locations of scheduled waypoints 114 (shown in
The fourth column 308 may be used to calculate the statistical measure of adherence to a schedule for the vehicle 108, 110, or 112 (shown in
Alternatively, the congestion module 206 may count the number of scheduled waypoints 114 (shown in
Returning to the discussion of the scheduling system 100 shown in
Alternatively, the congestion module 206 may calculate the statistical measure of adherence by the vehicle 108, 110, or 112 (shown in
In another embodiment, the congestion module 206 may calculate the average statistical measure of adherence by comparing the deviation of each vehicle 108, 110, 112 (shown in
The congestion module 206 determines the throughput parameter of the transportation network 102 (shown in
As described above, the movement plan of the transportation network 102 (shown in
As the vehicles 108, 110, 112 (shown in
In another example, if the yielding vehicle 110 is behind schedule and the passing vehicle 112 is on schedule or ahead of schedule, the scheduling system 100 may direct the passing vehicle 112 to slow down to allow for the yielding vehicle 110 to have sufficient time to reach and move onto the siding section route 106 before the passing vehicle 112 reaches the same siding section route 106. For example, the yielding vehicle 110 may be behind schedule and may not be able to completely enter the siding section route 106 of a meet event before the passing vehicle 112 arrives at the meet event. The yielding vehicle 110 may be unable to completely enter the siding section route 106 when one or more cars or units of the yielding vehicle 110, or a portion thereof, is still on the main line route 104 or is still transitioning from the main line route 104 to the siding section route 106 at the originally scheduled time of the meet event, or within a predetermined time buffer of the originally scheduled time. In such a situation, the scheduling system 100 may direct the passing vehicle 112 to slow down such that the yielding vehicle 110 is completely disposed on the siding section route 106 (e.g., no cars, units, or portions of the yielding vehicle 110 are on the main line route 104) when the passing vehicle 112 arrives at the meet event, or when the passing vehicle 112 reaches a waypoint disposed ahead of the meet event. Such slowing down by the vehicle 110 or 112 can result in fuel savings since the vehicle 110 or 112 may consume less fuel when moving slower.
The originally scheduled location or waypoint 114 (shown in
In order to modify the original meet event to an updated meet event, the modification module 208 of the scheduling system 100 determines a confidence parameter that changing the original meet event does not negatively impact the throughput parameter of the transportation network 102 (shown in
If the confidence parameter determined by the modification module 208 is sufficiently high, the modification module 208 can adjust the original meet event to an updated meet event, as described below. The relatively high confidence parameter can indicate that modifying the original meet event will not negatively impact the throughput parameter of the transportation network 102 (shown in
The vehicles 110, 112 are moving toward a meet event that involves both of the vehicles 110, 112. For example, the vehicle 110 may be the yielding vehicle and the vehicle 112 may be the passing vehicle in the meet event. The movement plan can include an original meet event that is scheduled to occur at the second, or middle, siding section route 106B. The location of the meet event can be the waypoint 114D for the yielding vehicle 110 as this may be the location at which the yielding vehicle 110 moves from the main line route 104 to the siding section route 106B to avoid collision with the passing vehicle 112. On the other hand, the location of the meet event for the passing vehicle 112 may be the waypoint 114F, or a location where the second siding section route 106B meets up with the main line route 104. The first and third siding section routes 106A, 106C represent alternate or potential meet events.
The modification module 208 (shown in
In one embodiment, the confidence parameter is based on a closing distance between one or more of the vehicles 110, 112 and a location of the original meet event. The “closing distance” means a distance between a current location of a vehicle 110, 112 and a scheduled location (e.g., a location of a meet event). For example, the confidence parameter may be based on the closing distance between the yielding vehicle 110 and the original location of the meet event (e.g., the waypoint 114D for the yielding vehicle 110) and/or between the passing vehicle 112 and the original location of the meet event (e.g., the waypoint 114F for the passing vehicle 112).
The confidence parameter may be inversely related to the closing distance of the yielding and/or passing vehicle 110, 112. For example, the confidence parameter may be smaller for a larger closing distance (e.g., the yielding vehicle 110 is farther from the meet location) and the confidence parameter may increase as the closing distance decreases (e.g., as the yielding vehicle 110 moves toward the meet location). The confidence parameter may be inversely related to the closing distance because, as the vehicle 110 and/or 112 is farther from the location of the meet event, there can be a greater possibility or chance that the yielding vehicle 110 has additional scheduled or unscheduled delays in arriving at the meet event. A scheduled delay may include a scheduled stop of the yielding vehicle 110 (e.g., to drop off and/or pick up passengers or cargo). An unscheduled delay may include an unplanned obtrusion blocking the main line route 104, a change in the movement plan for the yielding vehicle 110 to cause another vehicle having a higher priority than the yielding vehicle 110 to travel along the main line route 104 shown in
In one embodiment, the confidence parameter has a value that is based on the number of potential alternate locations for meet events between the originally scheduled location of a meet event and one or more of the vehicles 110, 112. For example, with respect to the embodiment shown in
The modification module 208 (shown in
In one embodiment, the confidence parameter has an initial value when no alternate locations for the meet event are located between the current location of the yielding vehicle 110 (or the passing vehicle 112) and the original location of the meet event. This initial value can be 1.0, 100%, or some other number. The value of the confidence parameter can decrease as more alternate locations for the meet event are disposed between the current location of the yielding vehicle 110 (or the passing vehicle 112) and the original location of the meet event. The relationship between the confidence parameter and the closing distance between the yielding vehicle 110 (or the passing vehicle 112) and the original location of the meet event may be a linear relationship. For example, the confidence parameter may decrease by a fixed or predetermined amount for each unit of distance and/or for each alternate location of a meet event in the closing distance between the yielding vehicle 110 (or the passing vehicle 112) and the original location of the meet event. Alternatively, the relationship between the confidence parameter and the closing distance between the yielding vehicle 110 (or the passing vehicle 112) and the original location of the meet event may be a non-linear relationship. For example, the confidence parameter may decrease by a changing or different amount for each unit of distance and/or for each alternate location of a meet event in the closing distance between the yielding vehicle 110 (or the passing vehicle 112) and the original location of the meet event.
Table 1 below illustrates examples of different confidence parameters that may be calculated based on the closing distance or number of alternate locations for the meet event between the current location of the yielding vehicle 110 and the original location of the meet event:
In the Table 1, the first column lists different closing distances between the yielding vehicle 110 (or the passing vehicle 112) and the original location of the meet event. The closing distances are expressed in the number of waypoints 114, such as the number of scheduled waypoints 114 disposed between the current location of the yielding or passing vehicle 110, 112 and the original location of the meet event. Alternatively, the closing distances can be expressed in the actual distance between the current location of the yielding or passing vehicle 110, 112 and the original location of the meet event.
In another embodiment, the closing distance used by the modification module 208 (shown in
The third column lists examples of corresponding confidence parameters that may be calculated by the modification module 208 (shown in
The modification module 208 (shown in
In one embodiment, if the confidence parameter exceeds the confidence threshold, then the confidence parameter may indicate that the meet event can be modified, such as by delaying the scheduled time of the meet event for the yielding vehicle 110, without significantly impacting or decreasing the throughput parameter of the transportation network 102. On the other hand, if the confidence parameter does not exceed the confidence threshold, then the confidence parameter may indicate that the meet event cannot be modified, such as by delaying the scheduled time of the meet event for the yielding vehicle 110, without significantly impacting or decreasing the throughput parameter of the transportation network 102. If the confidence parameter exceeds the confidence threshold, then the modification module 208 (shown in
The ETA of the yielding and/or passing vehicle 110, 112 represents the time at which the yielding and/or passing vehicle 110, 112 is expected to arrive at the location of the meet event. In order to calculate the ETA of the yielding or passing vehicle 110, 112, the modification module 208 may determine the closing distance between the yielding or passing vehicle 110, 112 and the location of the meet event, as well as the speed of the yielding or passing vehicle 110, 112. In one embodiment, the modification module 208 assumes that the yielding or passing vehicle 110, 112 is traveling at a predetermined speed, such as route speed, or the speed limit that is allowed on the section of the main line route 104 that the yielding or passing vehicle 110, 112 is traveling. Alternatively, the yielding or passing vehicle 110, 112 may periodically or continually transmit the current speed of the yielding or passing vehicle 112 to the modification module 208 via the antenna 116 (shown in
The slack time period may be a scheduled period of time between arrival of the yielding vehicle 110 at the location of the meet event and arrival of the passing vehicle 112 at the meet event. Alternatively, the slack time period may be a scheduled period of time between the yielding vehicle 110 being off of the main line route 104 and completely onto the siding section route 106 and arrival of the passing vehicle 112 at the meet event. The location of the yielding vehicle 110 may be the intersection between the main line route 104 and the siding section route 106 of the meet event where the yielding vehicle 110 moves off of the main line route 104. The slack time period is a safety buffer of time that is built into the schedules of the yielding and passing vehicles 110, 112 as a precaution against the yielding and/or passing vehicles 110, 112 arriving too early at a meet event and risking collision between the yielding and passing vehicles 110, 112.
In one embodiment, the modification module 208 (shown in
In another embodiment, the modification module 208 (shown in
With respect to changing the location of the meet event, the modification module 208 (shown in
The modification module 208 (shown in
The modification module 208 (shown in
If the potential location associated with the identified confidence parameter is a different location than the original location of the meet event, then the identified confidence parameter may indicate that changing the original location of the meet event to the location associated with the identified confidence parameter is unlikely to reduce the throughput parameter of the transportation network 102. The identified confidence parameter also may indicate that changing the location of the meet event to another location that is not associated with the identified confidence parameter or keeping the original location of the meet event may increase or is likely to reduce the throughput parameter of the transportation network. If the potential location associated with the identified confidence parameter is the same location as the original location of the meet event, then the identified confidence parameter may indicate that keeping the original location of the meet event is unlikely to reduce the throughput parameter of the transportation network 102. The identified confidence parameter also may indicate that changing the location of the meet event to another location that is not associated with the identified confidence parameter may increase or is likely to reduce the throughput parameter of the transportation network.
The modification module 208 (shown in
In another embodiment, the confidence parameters calculated by the modification module 208 (shown in
Returning to the discussion of the scheduling system 100 shown in
The communication module 210 identifies which vehicle 108, 110, 112 are addressed by the updated meet event and transmits the updated meet event to the addressed vehicle 108, 110, 112. For example, the communication module 210 may wirelessly transmit the updated time of the updated meet event to the yielding vehicle 110. The modification module 208 can generate several updated meet events at the same time or at approximately the same time. The communication module 210 transmits the updated meet events to the several vehicles 108, 110, 112 having schedules that are affected by the updated meet event. The communication module 210 can transmit the updated meet events to the vehicles 108, 110, 112 as the vehicles 108, 110, 112 are moving toward the meet events. For example, instead of communicating the updated meet events when the vehicles 108, 110, 112 are stationary, the communication module 210 can transmit the updated meet events as the vehicles 108, 110, 112 are in motion and progressing toward the meet events that are updated.
The vehicles 108, 110, 112 to whom the updated meet events are addressed receive the updated meet events and may change operations in response thereto. For example, one or more of the vehicles 108, 110, 112 may reduce tractive efforts to slow down the one or more of the vehicles 108, 110, 112 to arrive at the updated meet event at the updated time and/or location. In one embodiment, the antenna 118 of the yielding vehicle 110 receives the updated meet event from the scheduling system 100. The energy management system 120 in the yielding vehicle 110 examines the updated meet event to determine if the tractive effort and/or braking effort of the yielding vehicle 110 should be changed based on the updated meet event. For example, if the updated meet event includes a delayed time for the yielding vehicle 110 to arrive at the meet event, then the energy management system 120 may determine that the yielding vehicle 110 can slow down or reduce speed and conserve fuel in order to arrive at the updated meet event at the updated time. As a result, the energy management system 120 generates a directive to an operator to reduce a throttle setting to be displayed on the display device 124 and/or automatically reduces the throttle setting of the propulsion subsystem 122, for example. The yielding vehicle 110 may then reduce speed and fuel consumption while arriving at the meet event at the updated time. Alternatively, the energy management system 120 may change which siding section route 106 is used by the yielding and/or passing vehicle 110, 112 for the updated meet event. The updated location may be visually presented to the operator of the yielding and/or passing vehicle 110, 112 and/or used by the energy management system 120 to direct the yielding and/or passing vehicle 110, 112 to proceed to the updated location of the meet event.
In another embodiment, the antenna 118 of the passing vehicle 112 receives the updated meet event from the scheduling system 100. The energy management system 120 in the passing vehicle 112 examines the updated meet event to determine if the tractive effort and/or braking effort of the passing vehicle 112 should be changed based on the updated meet event. For example, the updated meet event may include a delayed time for the passing vehicle 112 to arrive at the meet event when the yielding vehicle 110 is behind schedule and may not entirely exit off of the main line route 104 before the originally scheduled meet event. In order to avoid the passing vehicle 112 having to abruptly slow down (e.g., by having the operator take control of the passing vehicle 112 such that the energy management system 120 does not control tractive efforts of the passing vehicle 112) and/or stop, the scheduling system 100 may instruct the passing vehicle 112 of an updated time of the meet event.
The energy management system 120 may determine that the passing vehicle 110 can slow down or reduce speed and conserve fuel in order to arrive at the updated meet event at the updated time. As a result, the energy management system 120 generates a directive to an operator to reduce a throttle setting to be displayed on the display device 124 and/or automatically reduces the throttle setting of the propulsion subsystem 122, for example. The passing vehicle 112 may then reduce speed and fuel consumption while arriving at the meet event at the updated time such that the yielding vehicle 110 is able to pull off of the main line route 104 and onto the siding section route 106 in time.
By slowing down the passing vehicle 112 under the control of the energy management system 120 instead of the operator or other system taking control of the energy management system 120 (e.g., to abruptly slow down), less fuel may be consumed in getting the passing vehicle 112 to the updated meet event. For example, if an updated time is not determined by the scheduling system 100, an operator on the passing vehicle 112 may abruptly slow down or stop movement of the passing vehicle 112 to avoid arriving at the meet event before the yielding vehicle 110 is able to pull off of the main line route 104. The operator may do so when a yellow or red signal light is seen alongside the main line route 104. The abrupt slowing down or stopping of the passing vehicle 112 may cause the energy management system 120 to stop controlling the tractive efforts of the passing vehicle 112 in an energy or fuel efficient manner, which can result in additional fuel being consumed than would be consumed if the energy management system 120 maintained control of the passing vehicle 112.
In another embodiment of the inventive subject matter disclosed herein, the movement plan for a transportation network can include pass events between two or more vehicles. A pass event can occur when first and second vehicles simultaneously travel in the same (e.g., common) direction on the same main section of a route with the first vehicle leading the second vehicle, and the first vehicle pulls off of the main section of the route onto a siding section of the route to allow the second vehicle to pass the first vehicle along the main section of the route. The pass event can be defined as a location and time at which the second vehicle (referred to herein as the “overtaking vehicle”) is scheduled to pass the first vehicle (referred to herein as the “leading vehicle”) on a common section of a route. For example, a pass event can include a location in the transportation network that includes a main line of a rail track having a siding section of the track. During the pass event, the leading vehicle moves off of the main line of the track to the siding section of the track and may stop or slow while the overtaking vehicle continues to move along the main line track and pass the leading vehicle.
As described above, a scheduling system can monitor a throughput parameter of the transportation network. The scheduling system can determine a confidence parameter that represents a probability that changing a speed of one or more vehicles arriving at a pass event will not negatively impact the throughput parameter. For example, if the overtaking vehicle is a faster vehicle than the leading vehicle and is relatively close behind the leading vehicle, the scheduling system may determine a low probability that slowing the overtaking vehicle will negatively impact (e.g., reduce) the throughput parameter. As another example, if the leading vehicle is relatively far ahead of the overtaking vehicle, the scheduling system may determine a low probability that slowing the leading vehicle will negatively impact the throughput parameter.
Similar to modifying a meet event, the scheduling system can modify the pass event and transmit the modified pass event to one or more of the vehicles. The vehicles may proceed toward the pass event based on the modified details. For example, the overtaking vehicle may slow down to arrive at the pass event later than originally scheduled. As another example, the passing vehicle may slow down to arrive at the pass event later than originally scheduled. The slowing of the overtaking vehicle or the leading vehicle can increase fuel savings while avoiding significant increases in the congestion of the transportation network.
Returning to the discussion of
An originally scheduled pass event may be in the schedule of the leading vehicle 110 in a manner that directs the leading vehicle 110 to move to the siding section route 106 at a scheduled waypoint 800 (e.g., the intersection of the siding section route 106 and the main line route 104 that is closer to the vehicles 110, 112) at a scheduled time and remain on the siding section route 106 (e.g., slow down and/or stop) until the overtaking vehicle 112 passes the siding section route 106 on the main line route 104. The schedule may then direct the leading vehicle 110 to travel back onto the main line route 104 and proceed to another scheduled waypoint. With respect to the overtaking vehicle 112, the schedule may direct the overtaking vehicle 112 to proceed to and pass the siding section route 106 at a scheduled time at a scheduled waypoint 802.
The original pass event between the leading vehicle 110 and the overtaking vehicle 112 in the movement plan may be modified by the scheduling system 100 (shown in
In order to modify the time of the original pass event to an updated time, the modification module 208 (shown in
If the confidence parameter determined by the modification module 208 (shown in
In one embodiment, the confidence parameter is based on one or more of relative speeds of the leading vehicle 110 and the overtaking vehicle 112, a separation distance 804 between the leading vehicle 110 and the overtaking vehicle 112, and/or a closing distance 806 between the leading vehicle 110 and the siding section route 106 where the pass event is scheduled to occur. The speeds of the leading vehicle 110 and the overtaking vehicle 112 may be transmitted by the leading vehicle 110 and the overtaking vehicle 112 to the monitoring module 204 (shown in
The separation distance 804 can be measured as the distance between the overtaking vehicle 112 and the leading vehicle 110 along the main line route 104. For example, if the main line route 104 includes one or more turns or bends between the overtaking vehicle 112 and the leading vehicle 110, then the separation distance 804 may be measured along a corresponding path that includes the turns or bends and may not necessarily be the shortest distance between the overtaking vehicle 112 and the leading vehicle 110. In the illustrated embodiment, the separation distance 804 is shown as extending between the front or leading end of the overtaking vehicle 112 and the back or trailing end of the leading vehicle 110. However, if the overtaking vehicle 112 includes one or more other vehicles or cars joined or coupled with the overtaking vehicle 112 and disposed between the overtaking vehicle 112 and the leading vehicle 110, then the separation distance 804 may be measured from the front or leading end of the other vehicles and the back or trailing end of the leading vehicle 110. If the leading vehicle 110 includes one or more other vehicles or cars joined or coupled with the leading vehicle 110 and disposed behind the leading vehicle 110 and between the leading vehicle 110 and the overtaking vehicle 110, then the separation distance 804 may be measured from the back or trailing end of the other vehicles and the front or leading end of the overtaking vehicle 112.
The closing distance 806 can be measured as the distance between the leading vehicle 110 and the location of the pass event (e.g., the waypoint 800 at which the leading vehicle 110 pulls off of the main line route 104) along the main line route 104. As described above, if the main line route 104 includes one or more turns or bends between the leading vehicle 110 and the location of the pass event, then the closing distance 806 may be measured along a corresponding path that includes the turns or bends. In the illustrated embodiment, the closing distance 806 is shown as extending between the front or leading end of the leading vehicle 110 and the waypoint 800. If the leading vehicle 110 includes one or more other vehicles or cars joined or coupled with the leading vehicle 110 and disposed between the leading vehicle 110 and the waypoint 800, then the closing distance 806 may be measured from the front or leading end of the other vehicles and the waypoint 800.
The relative speeds of the leading vehicle 110 and the overtaking vehicle 112, the separation distance 804, and/or the closing distance 806 may be obtained by the monitoring module 204 (shown in
The confidence parameter may have a positive relationship or a direct relationship with at least one of the relative speeds of the leading vehicle 110 and/or the overtaking vehicle 112. For example, the confidence parameter may increase when the relative speed of the overtaking vehicle 112 to the leading vehicle 110 increases. The relationship between the confidence parameter and one or more of the relative speeds is a positive relationship when an increase in the one or more of the relative speeds results in a linear (e.g., proportional) or non-linear (e.g., non-proportional) increase in the confidence parameter. In one embodiment, the confidence parameter has a positive relationship with the relative speed of the overtaking vehicle 112 to the leading vehicle 110. For example, if the overtaking vehicle 112 is traveling faster than the leading vehicle 110, then the confidence parameter may be larger than when the overtaking vehicle 112 is traveling closer to the speed of the leading vehicle 110 or slower than the leading vehicle 110. The confidence parameter may increase when the overtaking vehicle 112 is traveling faster than the leading vehicle 110 because delaying the time of the pass event such that the overtaking vehicle 112 slows down may not negatively impact other vehicles in the network. For example, in order to avoid a collision with the leading vehicle 110 or to avoid coming too close to the leading vehicle 110, the overtaking vehicle 112 may need to slow down and such slowing down may not negatively impact the throughput parameter because the throughput parameter may already be negatively impacted by the slower speed of the leading vehicle 110.
The confidence parameter may have a negative relationship or inverse relationship with the relative speed of the leading vehicle 110 to the overtaking vehicle 112. For example, if the leading vehicle 110 is traveling faster than the overtaking vehicle 112, then the confidence parameter may be smaller than when the leading vehicle 110 is traveling closer to the speed of the overtaking vehicle 112 or slower than the overtaking vehicle 112. The confidence parameter may decrease when the leading vehicle 110 is traveling faster than the overtaking vehicle 112 because delaying the time of the pass event may result in both the leading vehicle 110 and the overtaking vehicle 112 both slowing down. When both vehicles 110, 112 slow down, more vehicles may be delayed within the network.
As one example, the overtaking vehicle 112 may travel faster than the leading vehicle 110 such that the overtaking vehicle 112 may reach the leading vehicle 110 before the leading vehicle 110 reaches the siding section route 106 or that the overtaking vehicle 112 comes within a safety buffer distance from the leading vehicle 110 before the leading vehicle 110 reaches the siding section route 106. The relatively large relative speed of the overtaking vehicle 112 to the leading vehicle 110 may result in calculation by the modification module 208 (shown in
The confidence parameter may have a positive relationship or a direct relationship with the separation distance 804. For example, as the separation distance 804 increases, the confidence parameter also may increase such that there is a decreased chance that delaying the pass event will negatively impact the throughput parameter. When the separation distance 804 is relatively large, the leading vehicle 110 may be able to slow down to arrive at the pass event at a delayed time (relative to the originally scheduled time) such that the overtaking vehicle 112 is closer to the leading vehicle 110 when the leading vehicle 110 arrives at the siding section route 106. The decreased speed of the leading vehicle 110 may not negatively impact the throughput parameter of the network as the leading vehicle 110 otherwise would have to wait at the siding section route 106 for the overtaking vehicle 112 to arrive and pass. For example, decreasing the speed of the leading vehicle 110 may not negatively impact the throughput parameter any more or slightly more than the leading vehicle 110 pulling off onto the siding section route 106 and waiting for the overtaking vehicle 112.
The confidence parameter may have a negative relationship or an inverse relationship with the closing distance 806. For example, as the closing distance 806 decreases, the confidence parameter may increase. The confidence parameter may be inversely related to the closing distance 806 because, as the vehicle 110 and/or 112 is farther from the location of the pass event, there can be a greater possibility or chance that the leading vehicle 110 has additional scheduled or unscheduled delays in arriving at the meet event. Similar to the confidence parameter for meet events, in one embodiment, the confidence parameter for pass events can have a value that is based on the number of potential alternate locations for pass events between the originally scheduled location of a pass event and one or more of the vehicles 110, 112. For example, the confidence parameter may be inversely related to the number of other siding section routes 106 between the current location of the leading vehicle 110 and the location of the siding section route 106 that is originally or previously scheduled for the pass event. As described above, the confidence parameter may have a relatively low value when several alternate locations for the pass event are disposed between the leading vehicle 110 and the original location of the pass event. The confidence parameter can increase in value as the passing vehicle 110 moves toward the original location of the pass event.
The confidence parameter may be impacted differently by different factors. Based on a combination of the relative speed of the overtaking vehicle 112 to the leading vehicle 110, the separation distance 804, and/or the closing distance 806, the confidence parameter may change in value differently than if only one or a subset of these factors were considered. For example, if the relative speed of the overtaking vehicle 112 to the leading vehicle 110 is positive (e.g., the overtaking vehicle 112 is traveling faster than the leading vehicle 110), the separation distance 804 is relatively large, then the confidence parameter may still be relatively high, even if the closing distance 806 is relatively large. As another example, if the separation distance 804 is relatively large and the closing distance 806 is relatively small, then the confidence parameter may still be relatively high, even if the relative speed of the overtaking vehicle 112 to the leading vehicle 110 is small or negative. In another example, if the relative speed of the overtaking vehicle 112 to the leading vehicle 110 is relatively large or positive and the closing distance 806 is relatively small, the confidence parameter may be small if the separation distance 804 is relatively small.
Similar to as described above, the modification module 208 (shown in
In one embodiment, if the confidence parameter exceeds the confidence threshold, then the confidence parameter may indicate that the pass event can be modified, such as by delaying the scheduled time of the pass event or changing which siding section route 106 is used for the pass event. On the other hand, if the confidence parameter does not exceed the confidence threshold, then the confidence parameter may indicate that the pass event cannot be modified without decreasing the throughput parameter of the transportation network 102. If the confidence parameter exceeds the confidence threshold, then the modification module 208 (shown in
For example, the ETA of the vehicle 110, 112 can represent the time at which the leading and/or overtaking vehicle 110, 112 is expected to arrive at the location of the pass event. The slack time period may be a scheduled period of time between arrival of the leading vehicle 110 at the location of the pass event and arrival of the overtaking vehicle 112 at the pass event. Alternatively, the slack time period may be a scheduled period of time between the leading vehicle 110 being off of the main line route 104 and completely onto the siding section route 106 and arrival of the overtaking vehicle 112 at the pass event. The modification module 208 can delay the scheduled time of the pass event by an amount of time that results in the passing vehicle 110 arriving at the pass event by at least the slack time period before the overtaking vehicle 112 arrives at the meet event. In another embodiment, the confidence parameters calculated by the modification module 208 (shown in
Returning to the discussion of the scheduling system 100 shown in
The vehicles 108, 110, 112 to whom the updated meet events are addressed receive the updated pass events and may change operations in response thereto. For example, control units (e.g., control unit 712 shown in
In the illustrated embodiment, a plurality of vehicles 110, 112, such as rail vehicles, may be concurrently traveling on the separate route sections 900, 902 toward the converged route section 904. The vehicles 110, 112 are shown in
The movement plan for the transportation network 102 may include an originally scheduled convergence event that includes scheduled times and a scheduled location for the convergence event. The times of the convergence event may be the times that each of the vehicles 110, 112 is to proceed from the corresponding separate route section 900, 902 to the converged route section 904 (e.g., pass through the convergence point 906 onto the converged route section 904). The location for the convergence event may be the geographic location of the convergence point 906. The convergence point 906 may be a waypoint of the transportation network 102, such as one of the waypoints 114 (shown in
An original convergence event between the vehicles 110, 112 in the movement plan may be modified by the scheduling system 100 (shown in
In order to modify the time of the convergence event to an updated time, the modification module 208 (shown in
If the confidence parameter determined by the modification module 208 (shown in
The confidence parameter may be based on a closing distance between one or more of the vehicles 110, 112 and the location of the convergence event. The “closing distance” can mean the distance between a current location of a vehicle 110, 112 and the convergence point 906. The confidence parameter may be inversely related to the closing distance between the leading vehicle 110 and the convergence point 906 and/or the closing distance between the following vehicle 112 and the convergence point 906. For example, the confidence parameter may be smaller for a larger closing distance but may increase as the closing distance decreases. The confidence parameter may be inversely related to the closing distance because, as the vehicle 110 and/or 112 is farther from the location of the convergence event, there can be a greater possibility or chance that one or more of the vehicles 110, 112 has additional scheduled or unscheduled delays in arriving at the convergence event.
Similar to as described above, the modification module 208 (shown in
If the confidence parameter exceeds the confidence threshold, then the modification module 208 (shown in
The modification module 208 communicates the updated convergence event to the communication module 210. The communication module 210 determines which vehicles 108, 110, 112 in the transportation network 102 are to receive the updated time of the updated convergence event. The communication module 210 transmits the updated convergence event to the appropriate vehicle 108, 110, 112, as described above. The corresponding vehicles 108, 110, 112 receive the updated convergence event and may change operations in response thereto. For example, control units (e.g., control unit 712 shown in
Delaying the time of a convergence event can reduce the fuel consumed by a following vehicle 112 that will arrive at the convergence event before a leading vehicle 110. For example, instead of stopping movement, waiting for the leading vehicle 110 to arrive at the convergence event, and then re-starting movement to move to the converged route section 904, the following vehicle 112 may slow down as the following vehicle 112 approaches the convergence event. The following vehicle 112 may start slowing sufficiently far from the convergence event that the following vehicle 112 does not need to come to a complete stop to allow the leading vehicle 110 to pull onto the converged route section 906 ahead of the following vehicle 112. The slowing down of the following vehicle 112 may reduce the amount of fuel consumed by the following vehicle 112.
In another embodiment, the vehicles 110, 112 may be traveling on the converged route section 904 toward the separate route sections 900, 902. For example, instead of the vehicles 110, 112 converging onto the same route section 904, the vehicles 110, 112 may be diverging onto different route sections 900, 902. The movement plan for the transportation network 102 may include a scheduled divergence event that includes scheduled times and a scheduled location for the divergence event. The times of the divergence event may be the times that each of the vehicles 110, 112 is to proceed from the converged route section 904 to the divergent route sections 900, 902. The location for the divergence event may be the geographic location of the convergence point 906. The vehicle 110 or 112 that is ahead of the other vehicle 112 or 110 heading toward the divergent route sections 900, 902 may be referred to as the leading vehicle and the other vehicle may be referred to as the following vehicle.
A divergence event between the vehicles 110, 112 may be modified by the scheduling system 100 (shown in
In order to modify the time of the divergence event to an updated time, the modification module 208 (shown in
The confidence parameter may be based on a closing distance between one or more of the vehicles 110, 112 and the location of the divergence event. The confidence parameter may be inversely related to the closing distance between the leading vehicle and the convergence point 906 and/or the closing distance between the following vehicle and the convergence point 906. The confidence parameter may be inversely related to the closing distance because, as the vehicle and/or is farther from the location of the divergence event, there can be a greater possibility or chance that one or more of the vehicles 110, 112 has additional scheduled or unscheduled delays in arriving at the divergence event.
Similar to as described above, the modification module 208 (shown in
If the confidence parameter exceeds the confidence threshold, then the modification module 208 (shown in
The modification module 208 communicates the updated divergence event to the communication module 210. The communication module 210 determines which vehicles 108, 110, 112 in the transportation network 102 are to receive the updated time of the updated divergence event. The communication module 210 transmits the updated divergence event to the appropriate vehicle 108, 110, 112, as described above. The corresponding vehicles 108, 110, 112 receive the updated divergence event and may change operations in response thereto. For example, control units (e.g., control unit 712 shown in
In the illustrated embodiment, the powered rail vehicle 700 includes a communication device 710 that is communicatively coupled with the antenna 702 for communicating data with off-board components. For example, the communication device 710 can include a transceiver device that wirelessly transmits and receives data messages, such as updated meet events from the scheduling system 100 (shown in
The memory 714 may include a tangible and non-transitory computer readable storage medium, such as a computer hard drive, flash drive, RAM, ROM, EEPROM, and the like. The memory 714 can include one or more sets of instructions that direct the control unit 712 to perform various operations or steps. For example, the memory 714 can include software applications.
The control unit 712 may represent a hardware and/or software system that operates to perform one or more functions to control operations of the powered rail vehicle 700. For example, the control unit 712 may include one or more computer processors, controllers, or other logic-based devices that perform operations based on instructions stored on a tangible and non-transitory computer readable storage medium, such as the memory 714, for controlling tractive efforts and/or braking efforts of the powered rail vehicle 700. Alternatively, the control unit 712 may include a hard-wired device that performs operations based on hard-wired logic of the device. The control unit 712 shown in
The control unit 712 can receive data messages from the scheduling system 100 (shown in
The control unit 712 may use the updated location and/or updated time to change a speed of the powered rail vehicle 700 to arrive at the updated meet event or the updated pass event. For example, if the powered rail vehicle 700 is the yielding vehicle at the updated meet event and the powered rail vehicle 700 is running ahead of schedule or the updated location is closer to a current location of the powered rail vehicle 700 than an original location of the meet event, the control unit 712 may use the updated location and/or updated time to reduce the speed of the powered rail vehicle 700. As another example, if the powered rail vehicle 700 is the passing vehicle at the updated meet event and a yielding vehicle is running behind schedule, the control unit 712 may use the updated location and/or updated time to reduce the speed of the powered rail vehicle 700. The speed may be reduced such that the passing vehicle arrives at the meet event at a later time such that the yielding vehicle has sufficient time to pull off of the main line route 104. As another example, the powered rail vehicle 700 may use the updated location and/or updated time to reduce the speed of the powered rail vehicle 700 as the vehicle 700 approaches the updated pass event.
The control unit 712 may calculate a difference in speed based on the updated location and/or updated time that the powered rail vehicle 700 needs to slow down in order to arrive at the updated meet event or updated pass event at the updated location and/or updated time. The control unit 712 may then direct the propulsion subsystem 706 to reduce speed to arrive at the updated event at the updated location and/or updated time. The control unit 712 may change the speed of the powered rail vehicle 700 such that the vehicle that includes the powered rail vehicle 700 arrives at the updated event later than the vehicle would have originally arrived at the event prior to changing the speed.
In one embodiment, the energy management system 704 conveys the trip plan that is formed for a vehicle that includes the powered rail vehicle 700 to the control unit 712. As described above, the trip plan may be formed based on a trip profile for the vehicle and may dictate tractive efforts and/or braking efforts for different portions of the trip. The energy management system 704 may update the trip plan when an updated location and/or updated time is received from the scheduling system 100 (shown in
The control unit 712 can receive the updated or revised trip plan from the energy management system 704 and adjust the tractive effort and/or braking effort of the propulsion subsystem 706 accordingly. For example, if the updated trip plan dictates that a lower speed is to be used to arrive at the updated meet event, then the control unit 712 can direct the propulsion subsystem 706 to reduce the tractive effort provided by the propulsion subsystem 706.
At 502, two or more of the vehicles 108, 110, 112 (shown in
At 504, a throughput parameter of the transportation network 102 (shown in
At 506, one or more confidence parameters associated with changing a time of an event, such as a meet event, a pass event, a convergence event, and/or a divergence event, between two or more of the vehicles 108, 110, 112 (shown in
As described above, the confidence parameters represent a possibility or probability that changing the original time of the event to an updated time for at least one of the vehicles 108, 110, 112 will not reduce or significantly reduce the throughput parameter of the transportation network 102 (shown in
At 508, the confidence parameter is examined to determine if the confidence parameter indicates that changing the original time of the event to an updated time will reduce or is likely to reduce the throughput parameter of the transportation network 102 (shown in
In one embodiment, the confidence parameter is compared to a threshold. If the confidence parameter exceeds the threshold, then the confidence parameter may indicate that changing the time of the event will not reduce or is unlikely to reduce the throughput parameter of the transportation network 102 (shown in
At 510, the change in the time of the event is transmitted to one or more of the vehicles 108, 110, 112 (shown in
At 602, two or more of the vehicles 108, 110, 112 (shown in
At 604, a throughput parameter of the transportation network 102 (shown in
At 606, two or more confidence parameters associated with different potential locations for an event, such as a meet event or a pass event, are determined. For example, several confidence parameters each associated with a different siding section route 106 (shown in
Each of the confidence parameters in the set can represent a possibility or probability that using the associated location of the siding section route 106 (shown in
At 608, at least one of the confidence parameters in the set is identified. The identified confidence parameter may be selected based on a comparison among the confidence parameters in the set. In one embodiment, the confidence parameter that is greater than one or more or all of the other confidence parameters in the set is identified. Alternatively, another confidence parameter is identified.
At 610, the identified confidence parameter from the set is examined to determine if the identified confidence parameter indicates that changing the original location of the event to an updated location will reduce or is likely to reduce the throughput parameter of the transportation network 102 (shown in
In one embodiment, the identified confidence parameter is compared to a threshold. If the identified confidence parameter exceeds the threshold, then the identified confidence parameter may indicate that changing the location of the event to another siding section route 106 (shown in
At 612, the change in the location of the event is transmitted to one or more of the vehicles 108, 110, 112 (shown in
While the methods 500, 600 shown in
In one embodiment, a system (e.g., an off-board scheduling system) includes a monitoring module, a congestion module, a modification module, and a communication module. The monitoring module is configured to monitor plural separate vehicles traveling in a transportation network according to a movement plan of the network. The movement plan directs the vehicles to move through the network according to schedules associated with the separate vehicles and includes an original meet event between a yielding vehicle and a passing vehicle of the separate vehicles. The congestion module is configured to calculate a throughput parameter of the network that is representative of a statistical measure of adherence to the movement plan by the separate vehicles. The modification module is configured to determine a confidence parameter representative of a probability that changing the original meet event does not reduce the throughput parameter of the network. The modification module also is configured to modify the original meet event to an updated meet event when the confidence parameter exceeds a predetermined threshold. The communication module is configured to transmit the updated meet event to one or more of the yielding vehicle or the passing vehicle as at least one of the yielding vehicle or the passing vehicle is moving toward the original meet event, for the one or more of the yielding vehicle or the passing vehicle to receive the updated meet event from the communication module and change a speed of the yielding vehicle or the passing rail vehicle to arrive at the updated meet event.
In another aspect, the communication module is configured to transmit a plurality of the updated meet events to two or more of the plural separate vehicles.
In another aspect, the original meet event is associated with at least one of an original location or an original time of the original meet event, and the updated meet event is associated with at least one of an updated location that differs from the original location or an updated time that differs from the original time for the updated meet event to occur.
In another aspect, for the updated meet event, the yielding vehicle is configured to move from a main line track in the network to a connected siding section track in the network and the passing vehicle is configured to continue along and pass the yielding vehicle on the main line track at at least one of a location or a time of the updated meet event.
In another aspect, the monitoring module is configured to track at least one of a current location of the yielding vehicle or a current location of the passing vehicle. The modification module also is configured to determine the confidence parameter based on a remaining distance between an original location of the original meet event and the at least one of the current location of the yielding vehicle or the current location of the passing vehicle.
In another aspect, the modification module is configured to calculate the confidence parameter based on an inverse relationship between the confidence parameter and the remaining distance.
In another aspect, the network includes a plurality of potential locations for the updated meet event disposed between the yielding vehicle and the passing vehicle. The modification module is configured to calculate the confidence parameter based on a number of the potential locations disposed between at least one of the yielding vehicle or the passing vehicle and the original location of the meet event.
In another aspect, the modification module is configured to calculate the confidence parameter such that the confidence parameter decreases as the number of the potential locations between the at least one of the yielding vehicle or the passing vehicle and an original location of the original meet event increases.
In another aspect, the modification module is configured to determine the confidence parameter for each of the plurality of potential locations for the updated meet event. The modification module is configured to change an original location of the original meet event to an updated location based on a comparison between the confidence parameters determined for the plurality of potential locations.
In another aspect, the communication module is configured to transmit at least one of the updated location or the updated time to one or more of the yielding vehicle or the passing vehicle for an energy management system disposed on-board the yielding vehicle or the passing vehicle to modify the speed of the yielding vehicle or the passing vehicle based on the at least one of an updated location or an updated time of the updated meet event.
In another aspect, the modification module is configured to delay arrival of the yielding vehicle at the original meet event when the passing vehicle is traveling to arrive at the original meet event later than an originally scheduled time of the original meet event.
In another aspect, the modification module is configured to delay arrival of the passing vehicle at the original meet event when the yielding vehicle is traveling to pull off a main line route onto a siding section route after an originally scheduled time of the original meet event.
In another embodiment, a method (e.g., a method for adjusting a movement plan of a transportation network) is provided that includes monitoring plural separate vehicles traveling in the transportation network according to a movement plan of the network. The movement plan directs the vehicles to move through the network according to schedules associated with the separate vehicles. The movement plan includes an original meet event between a yielding vehicle and a passing vehicle of the separate vehicles. The method also includes determining a throughput parameter of the network that is representative of a statistical measure of adherence to the movement plan by the separate vehicles, determining a confidence parameter representative of a probability that changing at least one of an original location or an original time of the original meet event does not reduce the throughput parameter of the network, modifying at least one of the original location or the original time of the original meet event to at least one of an updated location or an updated time of an updated meet event when the confidence parameter exceeds a predetermined threshold, and transmitting at least one of the updated location or the updated time to one or more of the yielding vehicle or the passing vehicle as at least one of the yielding vehicle or the passing vehicle is moving toward the location of the original meet event.
In another aspect, transmitting in the method includes transmitting the at least one of the updated location or the updated time for the one or more of the yielding vehicle or the passing vehicle to receive the at least one of the updated location or the updated time and change a speed of the yielding vehicle or the passing rail vehicle to arrive at the updated meet event.
In another aspect, monitoring includes tracking at least one of a current location of the yielding vehicle or a current location of the passing vehicle. The confidence parameter is based on a remaining distance between the original location of the original meet event and the at least one of the current location of the yielding vehicle or the current location of the passing vehicle.
In another aspect, the network includes a plurality of potential locations for the updated meet event disposed between the yielding vehicle and the passing vehicle. The confidence parameter is based on a number of the potential locations disposed between at least one of the yielding vehicle or the passing vehicle and the original location of the original meet event.
In another aspect, the confidence parameter decreases as the number of the potential locations between the at least one of the yielding vehicle or the passing vehicle and the original location of the original meet event increases.
In another aspect, the step of determining the confidence parameter includes determining the confidence parameter for each of the plurality of potential locations for the updated meet event, and the modifying step includes changing the original location of the original meet event to the updated location based on a comparison between the confidence parameters determined for the plurality of potential locations.
In another aspect, the transmitting step includes transmitting at least one of the updated location or the updated time to one or more of the yielding vehicle or the passing vehicle for an energy management system disposed on-board the yielding vehicle or the passing vehicle to modify the speed of the yielding vehicle or the passing vehicle based on the at least one of the updated location or the updated time.
In another aspect, modifying the at least one of the original location or the original time includes delaying arrival of the yielding vehicle at the original meet event when the passing vehicle is traveling to arrive at the original meet event later than the original time of the original meet event.
In another aspect, modifying the at least one of the original location or the original time includes delaying arrival of the passing vehicle at the original meet event when the yielding vehicle is traveling to pull off a main line route onto a siding section route after the original time of the original meet event.
In another embodiment, a computer readable storage medium for a system having a processor (e.g., an off-board scheduling system of a transportation network) is provided. The computer readable storage medium includes one or more sets of instructions configured to direct the processor to monitor plural separate vehicles traveling in the transportation network according to a movement plan of the network. The movement plan directs the vehicles to move through the network according to schedules associated with the separate vehicles. The movement plan includes an original meet event between a yielding vehicle and a passing vehicle of the separate vehicles. The one or more sets of instructions also are configured to direct the processor to determine a throughput parameter of the network that is representative of a statistical measure of adherence to the movement plan by the separate vehicles and determine a confidence parameter representative of a probability that changing at least one of an original location or an original time of the original meet event does not reduce the throughput parameter of the network. The one or more sets of instructions are further configured to direct the processor to modify at least one of the original location or the original time of the original meet event to at least one of an updated location or an updated time of an updated meet event when the confidence parameter exceeds a predetermined threshold and to transmit at least one of the updated location or the updated time to one or more of the yielding vehicle or the passing vehicle as at least one of the yielding vehicle or the passing vehicle is moving toward the location of the original meet event, for the one or more of the yielding vehicle or the passing vehicle to receive the at least one of the updated location or the updated time and change a speed of the yielding vehicle or the passing rail vehicle to arrive at the updated meet event.
In another aspect, the computer readable storage medium is a tangible and non-transitory (e.g., not a transient signal) computer readable storage medium.
In another aspect, the one or more sets of instructions direct the processor to track at least one of a current location of the yielding vehicle or a current location of the passing vehicle, and the confidence parameter is based on a remaining distance between the original location of the original meet event and the at least one of the current location of the yielding vehicle or the current location of the passing vehicle.
In another aspect, the network includes a plurality of potential locations for the updated meet event disposed between the yielding vehicle and the passing vehicle. The confidence parameter is based on a number of the potential locations disposed between at least one of the yielding vehicle or the passing vehicle and the original location of the original meet event.
In another aspect, the one or more sets of instructions are configured to direct the processor to determine the confidence parameter for each of the plurality of potential locations for the updated meet event and change the original location of the original meet event to the updated location based on a comparison between the confidence parameters determined for the plurality of potential locations.
In another aspect, the one or more sets of instructions are configured to direct the processor to transmit at least one of the updated location or the updated time to one or more of the yielding vehicle or the passing vehicle for an energy management system disposed on-board the yielding vehicle or the passing vehicle to modify the speed of the yielding vehicle or the passing vehicle based on the at least one of the updated location or the updated time.
In another embodiment, a method (e.g., a method for directing movement of vehicles in a transportation network) includes, at one of a yielding vehicle or a passing vehicle, receiving from an off-board scheduling system at least one of an updated location or an updated time of a meet event of the yielding vehicle and the passing vehicle and changing a speed of said one of the yielding vehicle or the passing vehicle in response to said at least one of the updated location or the updated time to arrive at the meet event.
In another aspect, changing the speed comprises slowing said one of the yielding vehicle or the passing vehicle to arrive at the meet event later than the yielding vehicle or the passing vehicle would have originally arrived at the meet event prior to changing the speed.
In another aspect, changing the speed comprises providing said at least one of the updated location or the updated time to an energy management system disposed on board said one of the yielding vehicle or the passing vehicle, revising by the energy management system of a trip plan of said one of the yielding vehicle or the passing vehicle based on said at least one of the updated location or the updated time to form a revised trip plan, and controlling movement of said one of the yielding vehicle or the passing vehicle based on the revised trip plan.
In another embodiment, a system (e.g., an on-board control system of a vehicle) includes a control unit that is configured to be disposed on-board a first vehicle and to receive from an off board scheduling system at least one of an updated location or an updated time of a meet event of the first vehicle and a second vehicle. The control unit is configured to change a speed of said first vehicle in response to said at least one of the updated location or the updated time to arrive at the meet event.
In another aspect, the control unit is configured to slow down said first vehicle to arrive at the meet event later than the first vehicle would have originally arrived at the meet event prior to changing the speed.
In another aspect, the system also includes an energy management system configured to be disposed on-board the first vehicle and to form a trip plan that dictates tractive efforts of the first vehicle based on a trip profile. The energy management system is configured to receive said at least one of the updated location or the updated time and revise the trip plan based on said at least one of the updated location or the updated time to form a revised trip plan. The control unit is configured to control movement of said first vehicle based on the revised trip plan.
In another embodiment, a system (e.g., an on-board system of a vehicle) includes a control unit for a first vehicle and a computer readable storage medium. The computer readable storage medium has one or more sets of instructions that are configured to direct the control unit to receive at least one of an updated location or an updated time of a meet event of the first vehicle and a second vehicle from an off-board scheduling system and change a speed of the first vehicle in response to said at least one of the updated location or the updated time to arrive at the meet event.
In another aspect, the computer readable storage medium is a tangible and non-transitory (e.g., not a transient signal).
In another aspect, the one or more sets of instructions are configured to direct the control unit to slow said first vehicle to arrive at the meet event later than the first vehicle would have originally arrived at the meet event prior to changing the speed.
In another aspect, the one or more sets of instructions are configured to direct the control unit to receive a revised trip plan that is formed by an energy management system based on said at least one of the updated location or the updated time. The trip plan dictates tractive efforts provided by said first vehicle based on a trip profile. The one or more sets of instructions are configured to direct the control unit to control movement of said first vehicle based on the revised trip plan.
It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the inventive subject matter without departing from its scope. While the dimensions and types of materials described herein are intended to define the parameters of the inventive subject matter, they are by no means limiting and are exemplary embodiments. Many other embodiments will be apparent to one of ordinary skill in the art upon reviewing the above description. The scope of the inventive subject matter should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Further, the limitations of the following claims are not written in means-plus-function format and are not intended to be interpreted based on 35 U.S.C. §112, sixth paragraph, unless and until such claim limitations expressly use the phrase “means for” followed by a statement of function void of further structure.
This written description uses examples to disclose several embodiments of the inventive subject matter, including the best mode, and also to enable one of ordinary skill in the art to practice the embodiments of inventive subject matter, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the inventive subject matter is defined by the claims, and may include other examples that occur to one of ordinary skill in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
The foregoing description of certain embodiments of the present inventive subject matter will be better understood when read in conjunction with the appended drawings. To the extent that the figures illustrate diagrams of the functional blocks of various embodiments, the functional blocks are not necessarily indicative of the division between hardware circuitry. Thus, for example, one or more of the functional blocks (for example, processors or memories) may be implemented in a single piece of hardware (for example, a general purpose signal processor, microcontroller, random access memory, hard disk, and the like). Similarly, the programs may be stand alone programs, may be incorporated as subroutines in an operating system, may be functions in an installed software package, and the like. The various embodiments are not limited to the arrangements and instrumentality shown in the drawings.
As used herein, an element or step recited in the singular and proceeded with the word “a” or “an” should be understood as not excluding plural of said elements or steps, unless such exclusion is explicitly stated. Furthermore, references to “one embodiment” of the present inventive subject matter are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Moreover, unless explicitly stated to the contrary, embodiments “comprising,” “including,” or “having” an element or a plurality of elements having a particular property may include additional such elements not having that property.
This application claims priority benefit to U.S. Provisional Application No. 61/483,988, which was filed on May 9, 2011, and is titled “Off-Board Scheduling System And Method For Adjusting A Movement Plan Of A Transportation Network” (the “'988 application”). This application also is related to U.S. Nonprovisional application Ser. No. 13/307,582, which was filed on 30 Nov. 2011, and is titled “Scheduling System And Method For A Transportation Network,” and is identified by attorney docket number 252817 (552-0027US2) Network” (the “'582 application”). The entire disclosures of these applications (the '988 application and the '582 application) are incorporated by reference herein.
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