Patent Publication Number: US-2021165016-A1

Title: Pressure sensing probe

Description:
TECHNICAL FIELD 
     This disclosure generally relates to a probe, and more specifically to a pressure sensing probe. 
     BACKGROUND 
     Under certain conditions, vehicles are susceptible to wind-induced tip-over. For example, surface pressures that occur during high wind conditions can result in forces and moments that may cause a train to derail. Currently, real-time wind speed and direction data is insufficient to make safety decisions regarding vehicle operations in potentially high and/or unknown wind conditions. 
     SUMMARY 
     According to an embodiment, a probe includes a first facet associated with a first pressure port operable to measure a first wind pressure, a second facet associated with a second pressure port operable to measure a second wind pressure, and a third facet associated with a third pressure port operable to measure a third wind pressure. The second facet is adjacent to the first facet and the third facet adjacent to the second facet. The probe further includes a fourth facet adjacent to the third facet and a fifth facet adjacent to the fourth facet and to the first facet. The first facet, the second facet, the third facet, the fourth facet, and the fifth facet are located between a first end portion and a second end portion of the probe. 
     According to another embodiment, a method includes measuring a first wind pressure using a first pressure port associated with a first facet of a probe, measuring a second wind pressure using a second pressure port associated with a second facet of the probe, and measuring a third wind pressure using a third pressure port associated with a third facet of the probe. The second facet is adjacent to the first facet, the third facet is adjacent to the second facet and a fourth facet, the fourth facet is adjacent to a fifth facet, and the fifth facet is adjacent to the first facet. The first facet, the second facet, the third facet, the fourth facet, and the fifth facet are located between a first end portion and a second end portion of the probe. 
     According to yet another embodiment, one or more computer-readable storage media embody instructions that, when executed by a processor, cause the processor to perform operations including measuring a first wind pressure using a first pressure port associated with a first facet of a probe, measuring a second wind pressure using a second pressure port associated with a second facet of the probe, and measuring a third wind pressure using a third pressure port associated with a third facet of the probe. The second facet is adjacent to the first facet, the third facet is adjacent to the second facet and a fourth facet, the fourth facet is adjacent to a fifth facet, and the fifth facet is adjacent to the first facet. The first facet, the second facet, the third facet, the fourth facet, and the fifth facet are located between a first end portion and a second end portion of the probe. 
     Technical advantages of certain embodiments of this disclosure may include one or more of the following. The systems and methods described herein may improve safety based on rapid identification of wind conditions that may result in vehicle (e.g., train) blow-overs. Certain embodiments measure wind velocity relative to a vehicle using probes mounted to the vehicle. These wind velocity measurements may be used to determine whether wind-induced tip-over is imminent. 
     Certain embodiments described herein generate wind speed and wind direction data that may be communicated to vehicle operators, which enables the vehicle operators to take remedial actions such as slowing or stopping vehicles encountering dangerous wind conditions. For example, a train operator may slow down a train if the wind direction and wind speed data indicate that wind-induced tip-over is imminent or likely. The systems and methods described herein may provide a competitive advantage by more accurately identifying local wind states, which may allow vehicles that are not expected to encounter unsafe conditions to continue operations without being subjected to speed restrictions. Allowing vehicles to continue operations without being subjected to speed restrictions may provide a monetary advantage since speed restrictions can result in costly delays for transportation systems. 
     Certain embodiments of this disclosure utilize probes mounted to a locomotive of a train to measure wind velocity while the train is in motion. The probes may be located to fit within certain Association of American Railroads (AAR) locomotive shape and size clearances, which provides a safe and efficient wind measurement system. In certain embodiments, the probes do not have moving parts independent of the train, which increases reliability in measuring wind velocity. The systems and methods described herein may be ruggedized (e.g., hard wired) for industrial field use. Unlike many existing devices which are only accurate for headwinds, the systems and methods described herein measure both headwinds and crosswinds accurately. 
     The systems and methods described herein may provide real-time accurate local ambient wind speed and direction data for trains, which may reduce the number of unnecessary train stops and/or reduction of train speed caused by current less accurate high wind forecasts. The systems and methods described herein are adaptable to other modes of transportation. For example, the systems and methods described herein may be adaptable to road trucks to provide real-time in-motion wind speed and direction data to a driver and/or to a centralized database. As another example, the systems and methods described herein may be adaptable to an aircraft for enhanced measurement of headwind and crosswind during flight. As still another example, the systems and methods described herein may be adaptable to wind turbine nacelles for enhanced measurement of wind speed and direction, which may improve control and efficiency of power generation. 
     Other technical advantages will be readily apparent to one skilled in the art from the following figures, descriptions, and claims. Moreover, while specific advantages have been enumerated above, various embodiments may include all, some, or none of the enumerated advantages. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       To assist in understanding the present disclosure, reference is now made to the following description taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  illustrates an example system for determining wind velocity relative to a vehicle; 
         FIG. 2  illustrates a side view of the vehicle of  FIG. 1 ; 
         FIG. 3  illustrates a front view of the vehicle of  FIG. 1 ; 
         FIG. 4  illustrates an example method for determining wind velocity relative to a vehicle; 
         FIG. 5  illustrates an example probe that may be used by the system of  FIG. 1 ; 
         FIG. 6  illustrates an example port labeling scheme for the probe of  FIG. 5 ; 
         FIGS. 7A and 7B  illustrate an example method for determining wind velocity in accordance with the port labeling scheme of  FIG. 6 ; 
         FIG. 8  illustrates an example communication system that may be used by the system of  FIG. 1 ; 
         FIGS. 9A-9F  illustrate computational fluid dynamics (CFD) simulations used to investigate the system of  FIG. 1 ; 
         FIG. 9A  illustrates a CFD model domain used to investigate the system of  FIG. 1 ; 
         FIG. 9B  illustrates a train used in the CFD model domain of  FIG. 9A ; 
         FIG. 9C  illustrates a plan view of a simulated airflow around the train of  FIG. 9B ; 
         FIG. 9D  illustrates a front view of a simulated airflow around the train of  FIG. 9B ; 
         FIG. 9E  illustrates a perspective view of a simulated airflow around the train of  FIG. 9B ; 
         FIG. 9F  illustrates a top view of a simulated airflow around a probe of  FIG. 9E ; 
         FIG. 10  illustrates an example system for determining wind velocity relative to each railroad car of a train traversing a curve of a track; 
         FIG. 11  illustrates an example method for determining wind velocity relative to a railroad car of a train traversing a curve of a track; and 
         FIG. 12  illustrates an example computer system that may be used by the systems and methods described herein. 
     
    
    
     DETAILED DESCRIPTION 
     Known methods for measuring ambient wind speed and direction near a moving vehicle utilize lengthy booms or other support structures to move wind sensors outside of the vehicle&#39;s influence and/or disturbed air flow. These methods may be impractical for general service since the wind sensors are located outside the normal vehicular clearance envelope or are located on booms that fit within the clearance envelopes and are used for short-term tests but are impractical for normal train operations. Ground-based anemometers may be located too far apart or too far away from the moving vehicle to provide actionable, real-time wind speed and direction data. The systems and methods described herein account for these deficiencies by measuring the ambient wind speed and direction from the moving vehicle. 
     The systems and methods described herein use probes attached to a vehicle to measure wind speed and direction relative to the vehicle. In certain embodiments, a controller uses wind pressures received from the probes and algorithms to calculate ambient wind speed and direction data while correcting the data for errors due to the probe locations potentially being within disturbed airflow around the vehicle. The probes are five-sided probes with pressure ports on three or four of the five sides and a reference port at an end of the probe. Differential pressures are measured between the ports, and a calibration procedure is used to convert the differential pressure readings into wind speed and direction relative to the vehicle. 
       FIGS. 1 through 12  show example systems and methods for determining wind velocity relative to a vehicle.  FIG. 1  shows an example system for determining wind velocity relative to a vehicle, and  FIGS. 2 and 3  show a side view and a front view, respectively, of the vehicle used in  FIG. 1 .  FIG. 4  shows an example method for determining wind velocity relative to a vehicle.  FIG. 5  shows an example probe that may be used by the system of  FIG. 1 ,  FIG. 6  shows an example port labeling scheme for the probe of  FIG. 5 , and  FIGS. 7A and 7B  show an example method for determining wind velocity using the port labeling scheme of  FIG. 6 .  FIG. 8  shows an example communication system that may be used by the system of  FIG. 1 .  FIGS. 9A-9F  show CFD simulations used to investigate the system of  FIG. 1 .  FIG. 10  shows an example system for determining wind velocity relative to a railroad car of a train traversing a curve of a track, and  FIG. 11  shows an example method that may be used by the system of  FIG. 10 .  FIG. 12  shows an example computer system that may be used by the systems and methods described herein. 
       FIG. 1  illustrates an example system  100  for determining wind velocity relative to a vehicle. In the illustrated embodiment of  FIG. 1 , the vehicle is a locomotive  110 . System  100  of  FIG. 1  includes locomotive  110 , tracks  112 , one or more probes  130 , and one or more controllers  140 . System  100  or portions thereof may be associated with an entity, which may include any entity, such as a business, a company (e.g., a railway company, a transportation company, etc.), or a government agency (e.g., a department of transportation, a department of public safety, etc.). The elements of system  100  may be implemented using any suitable combination of hardware, firmware, and software. For example, the elements of system  100  may be implemented using one or more components of the computer system of  FIG. 12 . 
     Locomotive  110  represents any railed vehicle equipped to provide power for one or more railroad cars. Locomotive  110  may be used to pull the one or more railroad cars along one or more tracks  112 . Locomotive  110  may operate independent of the one or more railroad cars. Locomotive  110  may pull and/or push one or more railroad cars. For example, a rear end  113  of locomotive  110  may be attached to a front end of a first railroad car of a plurality of railroad cars such that locomotive  110  pulls the one or more railroad cars. As another example, a front end  114  of locomotive  110  may be attached to a rear end of a last railroad car of a plurality of railroad cars such that locomotive  110  pushes the one or more railroad cars. As still another example, the one or more railroad cars may have first locomotive  110  attached to a front end of the one or more railroad cars and second locomotive  110  attached to the rear end of the one or more railroad cars for a push-pull operation. The one or more railroad cars may be used to transport goods (e.g., coal, grain, intermodal freight, etc.) and/or beings (e.g., humans, livestock, etc.). Locomotive  110  may be a self-propelled engine driven by electricity, diesel, battery, and/or steam power. 
     Locomotive  110  may include a front portion  116  and a rear portion  118 . Locomotive  110  may be any suitable length measured from front end  114  to rear end  113  of locomotive  110 . A centerline  150  of locomotive  110  represents an imaginary line drawn perpendicular to a mid-point of the length of locomotive  110 . Front portion  116  of locomotive  110  represents the portion of locomotive  110  from centerline  150  to front end  114  of locomotive  110  and rear portion  118  of locomotive  110  represents the portion of locomotive  110  from centerline  150  to rear end  113  of locomotive  110 . Driver&#39;s compartment  122  of locomotive  110  represents the portion of locomotive  110  that houses controls necessary to operate locomotive  110  and/or one or more train operators (e.g., a driver, an engineer, a fireman, a driver&#39;s assistant, and the like). Driver&#39;s compartment  122  of locomotive  110  is located in first portion  116  of locomotive  110 . 
     One or more probes  130  are coupled to locomotive  110 . Probes  130  of system  100  represent instruments used to measure wind pressure. Each probe  130  includes one or more ports (e.g., pressure ports  550  of  FIG. 5 ). Each probe  130  directly outputs pressures associated with each of the one or more ports. One or more pressure lines (see, e.g., pressure lines  810  of  FIG. 8 ) may be hard wired to each probe  130  to communicate information to controller  140 . Each probe  130  may include one or more sensors operable to communicate information to controller  140 . Probes  130  are coupled to locomotive  110  such that at least one probe  130  is not located within an aerodynamic separation zone under any relative wind angle. The relative wind angle may be applied over 360 degrees of relative wind angles. Separation zones may form as airflow separates from the body of locomotive  110  and re-attaches at a region further downwind of locomotive  110 . Separation zones are discussed in more detail in  FIGS. 9A-9F  below. 
     Each probe  130  is attached to an outer surface of locomotive  110 . Probes  130  may be attached to an outer surface of front portion  116  of locomotive  110 . For example, probes  130  may be attached to an outer surface of driver&#39;s compartment  122  of locomotive  110 . Probes  130  may be attached to a top surface of locomotive  110 . The top surface of locomotive  110  is the outer surface of locomotive  110  that is visible in a plan view of locomotive  110 . In the illustrated embodiment of  FIG. 1 , the top surface of driver&#39;s compartment  122  includes a top flat surface  124  and two top angled surfaces  126  that slope downward toward tracks  112 . Each top angled surface  126  shares an edge with top flat surface  124 . 
     In the illustrated embodiment of  FIG. 1 , probes  130  of system  100  include probe  130   a  and probe  130   b.  Probe  130   a  is located near the intersection of front end  114 , top angled surface  126 , and a side surface  128  of locomotive  110 . Probe  130   b  may be similarly located on an opposite side of locomotive  110  such that a location of probe  130   b  mirrors the location of probe  130   a  about longitudinal axis  160  of locomotive  110 . 
     Controller  140  of system  100  represents any suitable computing component that may be used to process information for system  100 . Controller  140  may coordinate one or more components of system  100 . Controller  140  may receive data (e.g., wind pressure data) from one or more probes  130  of system  100 . Controller  140  may include a communications function that allows users (e.g., a technician, an administrator, a driver, a vehicle operator, etc.) to communicate with one or more components of system  100  directly. For example, controller  140  may be part of a computer (e.g., a laptop computer, a desktop computer, a smartphone, a tablet, etc.), and a user may access controller  140  through an interface (e.g., a screen, a graphical user interface (GUI), or a panel) of the computer. Controller  140  may communicate with one or more components of system  100  via a network (e.g., network  890  of  FIG. 8 ). Controller  140  may be located inside locomotive  110 . For example, controller  140  may be located in driver&#39;s compartment  122  of locomotive  110 . In certain embodiments, controller  140  may be located exterior to locomotive  110 . For example, controller  140  may operate in a cloud computing system. 
     Controller  140  may determine wind direction and/or wind speed relative to a vehicle (e.g., locomotive  110 ) of system  100  using information received from probes  130 . Controller  140  may determine wind direction and/or wind speed relative to the vehicle when the vehicle is in motion. For example, controller  140  may determine wind direction and/or wind speed relative to locomotive  110  in real-time or near real-time as locomotive  110  moves at a calculated speed along track  112 . Controller  140  may predict wind-induced tip-over of a vehicle (e.g., the locomotive and/or following cars) based on the determined wind direction and/or wind speed. Wind conditions resulting in tip-over may be determined using CFD simulations, wind tunnel tests, field tests, and the like. 
     Controller  140  may communicate the determined wind direction and/or wind speed to the entity associated with system  100 . For example, controller  140  may communicate the determined wind direction and/or wind speed to an operator (e.g., an operating crew) of locomotive  110 . As another example, controller  140  may communicate the determined wind direction and/or wind speed to a back-office system of the entity associated with system  100  to assist in the back office&#39;s decision making processes. 
     In certain embodiments, controller  140  may use the determined wind direction and/or wind speed to verify and/or validate weather information received from one or more weather sources. For example, controller  140  may verify and/or validate forecasted weather data (e.g., forecasted high winds) received from one or more weather sources. This validation process may save time and money by eliminating or reducing the need to dispatch personnel with hand-held anemometers to locations of forecasted high winds. The determined wind direction and/or wind speed provides local conditions at the vehicle (e.g., locomotive  100 ) at all locations. These conditions may be different from conditions at wayside stations due to impact of local topography, such as canyons, elevated sections of track, hills, and adjacent structures. 
     In operation, probe  130   a  and probe  130   b  coupled to locomotive  110  measure wind pressures while locomotive  110  is in motion and communicate the wind pressures to controller  140 . Controller  140  receives the wind pressure measurements from probe  130   a  and probe  130   b  and determines a wind angle and a wind speed relative to locomotive  110  using the one or more wind pressure measurements. Controller  140  communicates the wind angle and wind speed to an operator of locomotive  110  to enable the operator to take corrective actions as needed based on the wind angle and the wind speed. For example, the operator may decrease the speed of locomotive  110  to prevent a potential tip-over of locomotive  110 . As such, system  100  of  FIG. 1  determines wind angle and wind speed relative to locomotive  110 , which may prevent a wind-induced tip-over of locomotive  110 . 
     Although  FIG. 1  illustrates a particular arrangement of locomotive  110 , probe  130   a,  probe  130   b,  and controller  140 , this disclosure contemplates any suitable arrangement of locomotive  110 , probe  130   a,  probe  130   b,  and controller  140 . Locomotive  110 , probe  130   a,  probe  130   b,  and controller  140  of system  100  may be physically or logically co-located with each other in whole or in part. 
     Although  FIG. 1  illustrates a particular number of locomotives  110 , probes  130 , and controllers  140 , this disclosure contemplates any suitable number of locomotives  110 , probes  130 , and controllers  140 . For example, more than two probes  130  may be attached to locomotive  110 . As another example, locomotive  110  may be part of a train that includes more than one locomotive  110  and/or one or more railroad cars. 
     Modifications, additions, or omissions may be made to system  100  depicted in  FIG. 1 . System  100  may include more, fewer, or other components. For example, locomotive  110  of system  100  may be replaced with any suitable component used for transportation such as an automobile, a railroad car, a truck, a bus, an aircraft, a shipping vessel, and the like. As another example, locomotive  110  of system  100  may be any suitable shape. 
       FIG. 2  illustrates a side view  200  of locomotive  110  of  FIG. 1 . The illustrated embodiment of  FIG. 2  includes locomotive  110  and probe  130   a.  Locomotive  110  includes front end  114 , driver&#39;s compartment  122 , top flat surface  124 , and top angled surface  126 . Probe  130   a  is located at a corner of top angled surface  126 . 
     Probe  130   a  is physically attached to an outer surface of locomotive  110 . Probe  130   a  may be physically attached to the outer surface of locomotive  110  using one or more magnets, welds, bolts, adhesives, tape, and the like. Probe  130   a  may be physically attached to locomotive  110  such that probe  130   a  is fixed in position to locomotive  110 . Probe  130   a  may be restricted from movement independent of locomotive  110 . In certain embodiments, probe  130   a  has no moving parts independent of locomotive  110 . Moving parts require more maintenance and are more prone to failure than non-moving parts, especially when poor weather conditions are present. Rugged moving parts are generally not delicate, which is required for accurate measurements. 
     Probe  130   a  may be made of metal (e.g., nickel, titanium, copper, iron, steel (e.g., stainless steel), aluminum, etc.), plastic, fabric, a combination thereof, or any other suitable material. Probe  130   a  may be made of a material that can withstand sun, rain, hail, wind, snow, ice, sleet, and/or other weather conditions. Probe  130   a  may include one or more components operable to account for one or more weather conditions. For example, probe  130   a  may include a defrosting component. 
     Although  FIG. 2  illustrates a particular arrangement of locomotive  110  and probe  130   a,  this disclosure contemplates any suitable arrangement of locomotive  110  and probe  130   a.  Although  FIG. 2  illustrates a particular number of locomotives  110  and probes  130   a,  this disclosure contemplates any suitable number of locomotives  110  and probes  130   a . Modifications, additions, or omissions may be made to side view  200  depicted in  FIG. 2 . For example, locomotive  110  may be replaced with any suitable component used for transportation such as an automobile, a railroad car, a truck, a bus, an aircraft, a shipping vessel, and the like. As another example, side view  200  may be mirrored such that probe  130   a  is replaced with probe  130   b  of  FIG. 1 . Side view  200  of locomotive  110  may include more, fewer, or other components. 
       FIG. 3  illustrates a front view  300  of locomotive  110  of  FIG. 1 . Front view  300  includes locomotive  110  and probes  130 . Front end  114  of locomotive  110  includes the components of locomotive  110  illustrated in front view  300 . As shown, probe  130   a  is located on one side of centerline  150  of locomotive  110  and probe  130   b  is located on an opposite side of centerline  150  of locomotive  110 . Each probe  130  is operable to measure wind angles over a range of 180 degrees. 
     Each probe  130  is coupled to locomotive  110  such that each probe  130  is located within a clearance plate set by AAR Plate M  310  for the AAR Mechanical Division. Rolling stock in the rail industry that fits within AAR clearance plates is guaranteed safe clearance through known tunnels and past other known obstructions. For locomotive  110 , the relevant clearance plate is AAR Plate M  310 . 
     AAR Plate M  310  specifies a maximum height  320  and a maximum width  330  for cars. AAR Plate M  310  illustrates a car cross-section that tapers at each top corner. A compliant car (e.g., locomotive  110 ) must fit within the illustrated cross-section. Accordingly, a compliant car is not permitted to fill an entire rectangle of the maximum height  320  and maximum width  330 . The maximum height  320  for plate M is approximately 16′-0″ as measured from 2½ inches above the top of the rail of track  112 , and the maximum width  330  for plate M is 10′-8″. 
     To comply with AAR Plate M  310 , probe  130   a  and probe  130   b  each extend a maximum distance (e.g., eight inches) from an outer surface of locomotive  110 . The maximum distance depends on the size of locomotive  110  relative to the clearance plate dimensions of AAR Plate M  310 . Probe  130   a  and probe  130   b  each extend in a direction perpendicular to the outer surface of locomotive  110 . In some embodiments, probe  130   a  and/or probe  130   b  may extend from the outer surface of locomotive  110  at an angle. For example, probe  130   a  and/or probe  130   b  may extend vertically such that probe  130   a  and/or probe  130  extend perpendicular to a longitudinal axis (e.g., longitudinal axis  160  of  FIG. 1 ) of locomotive  110 . 
     Although  FIG. 3  illustrates a particular arrangement of locomotive  110  and probes  130 , this disclosure contemplates any suitable arrangement of locomotive  110  and probes  130 . Although  FIG. 3  illustrates a particular number of locomotives  110  and probes  130 , this disclosure contemplates any suitable number of locomotives  110  and probes  130 . For example, front view  300  may include more than two probes  130  (e.g., two probes  130  on either side of centerline  150 ). Modifications, additions, or omissions may be made to front view  300  depicted in  FIG. 3 . Front view  300  of locomotive  110  may include more, fewer, or other components. 
       FIG. 4  illustrates an example method  400  for determining wind velocity relative to a vehicle. Method  400  begins at step  410 . At step  420 , a controller (e.g., controller  140  of  FIG. 1 ) receives wind pressure measurements from one or more probes (e.g., probe  130   a  and probe  130   b  of  FIG. 1 ) coupled to a vehicle (e.g., locomotive  110  of  FIG. 1 ). For example, the controller may include transducers (e.g., transducers  820  of  FIG. 8 ), and the transducers may receive wind pressure measurements from one or more ports of the one or more probes. Method  400  then advances to step  430 . 
     At step  430 , the controller determines a wind angle relative to the vehicle using the wind pressure measurements received from the one or more probes. The controller may determine the wind angle relative to the vehicle using the method of  FIGS. 7A and 7B  described below. At step  440 , the controller determines a wind speed relative to the vehicle using the wind pressure measurements and the wind angle. The controller may determine the wind speed relative to the vehicle using the method of  FIGS. 7A and 7B  below. 
     At step  450 , the controller determines a type of vehicle. For example, the controller may determine a specific model of the vehicle (e.g., a specific model of a locomotive). The controller may receive information associated with a specific model of the vehicle such as a height of the vehicle, a width of the vehicle, a length of the vehicle, a shape of the vehicle, one or more components attached to the vehicle, and the like. At step  460 , the controller determines a weight of the vehicle. The controller may determine the weight of the vehicle using the information associated with the specific model of the vehicle. Method  400  then advances to step  470 . 
     At step  470 , the controller determines whether the vehicle has potential for wind-induced tip-over. The controller may determine whether the vehicle has potential for wind-induced tip-over based on the wind angle relative to the vehicle, the wind speed relative to the vehicle, the type of vehicle, the weight of the vehicle, a combination thereof, or any other suitable factor. For example, the controller may calculate a tipping moment for a locomotive and compare the tipping moment to a restoring moment. The restoring moment is the weight of the locomotive times the horizontal distance from the centerline of the locomotive to the rail. The tipping moment may be determined by comparing relative wind speed and direction to a lookup table based on previous aerodynamic studies for the particular vehicle (e.g., a CFD or wind tunnel study). If the tipping moment is greater than the restoring moment, the vehicle tips. More sophisticated models may include track inputs (e.g., non-smoothness), vehicle suspension details, vehicle rocking and swaying, and the like. 
     If the controller determines that the vehicle does not have potential for tip-over, method  400  advances from step  470  to step  490 , where method  400  ends. If the controller determines that the vehicle has potential for tip-over, method  400  advances from step  470  to step  480 , where the controller triggers an alarm. Triggering the alarm may send one or more signals (e.g., a verbal or written message) to an operator of the vehicle. For example, triggering the alarm may send a message to an operator of a locomotive to decrease the speed of the locomotive. In certain embodiments, triggering the alarm may initiate one or more automated actions. The automated actions may include decreasing the speed of the vehicle, stopping the vehicle, activating a siren, changing a direction of the vehicle, and the like. Method  400  then advances from step  480  to step  490 , where method  400  ends. 
     Modifications, additions, or omissions may be made to method  400  depicted in  FIG. 4 . Method  400  may include more, fewer, or other steps. For example, method  400  may include determining one or more separation zones associated with the vehicle and physically attaching at least one probe to the vehicle outside of the one or more separation zones. As another example, method  400  may include determining one or more clearance plate standards associated with the vehicle and physically attaching the one or more probes to the vehicle such that the locations of the probes comply with the one or more clearance plate standards. As still another example, method  400  may include determining, at step  470 , whether each vehicle in a series of vehicles (e.g., a series of railroad cars) has potential for wind-induced tip-over based on the wind angle and wind speed relative to each vehicle. Steps may be performed in parallel or in any suitable order. While discussed as specific components completing the steps of method  400 , any suitable component may perform any step of method  400 . 
       FIG. 5  illustrates a probe  130  that may be used by system  100  of  FIG. 1 . Probe  130  of  FIG. 5  may represent probe  130   a  and/or probe  130   b  of  FIG. 1 . Probe  130  is an instrument used to measure wind velocity. As air flow passes over and around probe  130 , the shape of probe  130  dictates a velocity pattern on an outer surface of probe  130 . Probe  130  includes multiple facets  510  and multiple pressure ports  550 . Pressure ports  550  of probe  130  are used to measure static pressures. By comparing the static pressures at the various pressure ports  550  of probe  130 , a measurement of wind velocity can be determined. 
     Probe  130  includes five facets  510 . Each facet  510  of probe  130  may be a machined, flat surface. Two or more facets  510  may be equal in width, length, size, shape, or a combination thereof. In certain embodiments, two or more facets  510  may be different in width, length, size, shape, or a combination thereof. A cross section of probe  130  has an outer shape of a pentagon. The pentagon may be a regular pentagon with equal sides and angles. The pentagon may be an irregular pentagon with unequal sides and/or angles. A five-sided probe  130  may offer optimal performance with the fewest pressure differentials, which may minimize cost. In alternative embodiments, probe  130  may include more or less than five facets  510  (e.g., three, four, or six facets  510 ). For example, probe  130  may include six facets  510  and have a cross-sectional shape of a hexagon. In certain embodiments, probe  130  may have one or more outer curved surfaces. For example, a cross section of probe  130  may have an outer shape of a circular cylinder. 
     Overall length  512  of probe  130  may be limited by one or more standards (e.g., the AAR standard). For example, overall length  512  of probe  130  may be a maximum of eight inches to fit within the clearance plate associated with AAR plate M. Probe  130  may have any suitable thickness. For example, a maximum thickness of probe  130  may be between two and three inches. 
     Probe  130  includes a tip  520 , a main body  530 , and a base  540 . Tip  520  of probe  130  has a shape of a spherical cone. A joint between tip  520  and each facet  510  of probe  130  forms a rounded edge. Tip  520  may be any suitable size and shape to accurately determine wind pressure relative to a vehicle. For example, tip  520  may be faceted in certain embodiments. Length  522  of tip  520  may be between 10 and 25 percent of length  512  of probe  130 . In certain embodiments, length  522  of tip  520  is within a range of one and two inches. 
     Main body  522  of probe  130  includes facets  510 . Main body  522  has a shape of a regular pentagon. Main body  522  may be any suitable size or shape to accurately determine wind velocity relative to a vehicle. Length  532  of main body  522  may be between 50 and 75 percent of overall length  512  of probe  130 . In certain embodiments, length  532  of main body  522  is within a range of four to six inches. 
     Base  540  of probe  130  has a shape of a cylinder. Base  540  may be any suitable size or shape to accurately determine wind velocity relative to a vehicle. Length  542  of base  540  may be between 20 and 40 percent of overall length  512  of probe  130 . In certain embodiments, length  532  of main body  522  is within a range of two to three inches. An outer edge of an end of base  540  attaches to a face of an end of main body  530  such that a joint between main body  530  and base  540  of probe  130  forms a perpendicular edge. 
     Tip  520 , main body  530 , and base  540  of probe  130  may be the same material (e.g., metal, plastic, fabric, etc.). In some embodiments, tip  520 , main body  530 , and base  540  of probe  130  may be different materials. Tip  520 , main body  530 , and base  540  of probe  130  may be manufactured as a single unit and/or in parts. 
     Pressure ports  550  of probe  130  are holes in probe  130  used to measure wind pressure (e.g., static pressure), wind speed, and/or wind direction. For example, pressure ports  550  may measure wind pressure, and a comparison of the relative pressure differentials between pressure ports  550  may be used to determine wind angle and/or wind speed relative to a vehicle. Probe  130  may include one or more pressure sensors to measure pressure at pressure ports  550 . For example, each pressure port  550  may have its own pressure sensor to measure pressure at that particular port. 
     Pressure ports  550  may be located on one or more facets  510  of probe  130 . For example, three facets  510  of probe  130  may each include a single pressure port  550 , whereas the remaining two facets  510  of probe  130  do not include a pressure port  550 . Tip  520  may include a pressure port  550 . For example, an end of tip  520  located furthest away from main body  530  of probe  130  may include one pressure port  550 . Pressure port  550  at tip  520  may be used to measure a reference pressure. The location of the reference pressure port  550  at the end of tip  520  of probe  130  may provide the most ideal location on probe  130  for measuring reference pressure because this location may be relatively insensitive to wind angle. Pressure ports  550  are described in more detail in  FIG. 6  below. 
     Although  FIG. 5  illustrates a particular arrangement of facets  510 , tip  520 , main body  530 , base  540 , and pressure ports  550 , this disclosure contemplates any suitable arrangement of facets  510 , tip  520 , main body  530 , base  540 , and pressure ports  550 . Modifications, additions, or omissions may be made to probe  130  depicted in  FIG. 5 . Probe  130  may include more, fewer, or other components. Probe  130  may have more or less than five facets  510 . Tip  520 , main body  530 , and/or base  540  of probe  130  may any suitable shape for measuring wind speed and/or direction. For example, main body  530  of probe  130  may have a cylindrical cross-sectional shape. In certain embodiments, probe  130  may not include tip  520  and/or base  540 . One or more components of probe  130  may be implemented using one or more components of the computer system of  FIG. 12 . 
       FIG. 6  illustrates a port labeling scheme  600  for probes  130  of  FIG. 1 . Port labeling scheme  600  may be used by the method of  FIGS. 7A and 7B  to determine wind direction and wind speed relative to a vehicle. Port labeling scheme  600  shows a schematic plan view of locomotive  110 , probe  130   a,  and probe  130   b.  In the illustrated embodiment, locomotive  110  is traveling in a direction  610  along longitudinal axis  160  of locomotive  110 . Locomotive  110  includes a front side  620 , a first side  630 , and a second side  640 . Front side  620  is located at a front end of locomotive  110 . 
     Probe  130   a  includes five facets (see, e.g., facets  510  of  FIG. 5 ). The five facets of probe  130   a  include facet  1   a,  facet  2   a,  facet  3   a,  facet  4   a,  and facet  5   a.  Facet  1   a  is adjacent to facet  2   a,  facet  2   a  is adjacent to facet  3   a,  facet  3   a  is adjacent to facet  4   a,  facet  4   a  is adjacent to facet  5   a,  and facet  5   a  is adjacent to facet  1   a  of probe  130   a.  Facets  1   a,    2   a,    3   a,    4   a , and  5   a  are connected to form a pentagon. In the illustrated embodiment, facet  2   a  and first side  630  of locomotive  110  face the same direction. Facets  1   a,    2   a,  and  3   a  of probe  130   a  face away from longitudinal axis  160  of locomotive  110  and facets  4   a  and  5   a  face toward longitudinal axis  160  of locomotive  110 . As such, facets  1   a,    2   a,  and  3   a  of probe  130   a  can measure wind angles over a range of zero to 180 degrees. 
     Probe  130   a  includes pressure ports (see, e.g., pressure ports  550  of  FIG. 5 ). The pressure ports are used to measure static pressure. The pressure ports of probe  130   a  include port  1   a,  port  2   a,  port  3   a,  and port  4   a.  Port  1   a  is located on facet  1   a,  port  2   a  is located on facet  2   a,  and port  3   a  is located on facet  3   a.  In the illustrated embodiment, facets  4   a  and  5   a  of probe  130   a  do not have pressure ports. Pressure ports are not included on facets  4   a  and  5   a  in this embodiment because facets  4   a  and  5   a  are frequently in a separation zone as locomotive  110  of  FIG. 1  travels in direction  610  and are thus not useful. Port  4   a  is located on the top (e.g., top center) of probe  130   a  when viewing probe  130   a  in plan view. Port  4   a  may be used as a reference pressure measurement. 
     Similar to probe  130   a,  probe  130   b  includes five facets (see, e.g., facets  510  of  FIG. 5 ). The five facets of probe  130   b  include facet  1   b , facet  2   b,  facet  3   b,  facet  4   b,  and facet  5   b.  Facet  1   b  is adjacent to facet  2   b,  facet  2   b  is adjacent to facet  3   b,  facet  3   b  is adjacent to facet  4   b,  facet  4   b  is adjacent to facet  5   b,  and facet  5   b  is adjacent to facet  1   b.  Facets  1   b,    2   b ,  3   b,    4   b,  and  5   b  are connected to form a pentagon. In the illustrated embodiment, facet  2   b  and second side  640  of locomotive  110  face the same direction. Facets  1   b,    2   b,  and  3   b  of probe  130   b  face away from longitudinal axis  160  of locomotive  110  and facets  4   b  and  5   b  face toward longitudinal axis  160  of locomotive  110 . As such, facets  1   b,    2   b,  and  3   b  of probe  130   b  can measure wind angles over a range of zero to 180 degrees. The combination of facets  1   a ,  2   a,  and  3   a  of probe  130   a  and facets  1   b,    2   b,  and  3   b  of probe  130   b  can measure wind angles over a range of zero to 360 degrees. 
     Similar to probe  130   a,  probe  130   b  includes pressure ports (see, e.g., pressure ports  550  of  FIG. 5 ). The pressure ports of probe  130   b  include port  1   b,  port  2   b,  port  3   b,  and port  4   b.  Port  1   b  is located on facet  1   b,  port  2   b  is located on facet  2   b,  and port  3   b  is located on facet  3   b.  In the illustrated embodiment, facets  4   b  and  5   b  of probe  130   b  do not have pressure ports. Port  4   b  is located on the top (e.g., top center) of probe  130   b  when viewing probe  130   b  in plan view. Port  4   b  may be used as a reference pressure measurement. 
     Although  FIG. 6  illustrates a particular arrangement of facets and pressure ports within port labeling scheme  600 , this disclosure contemplates any suitable arrangement of facets and ports within port labeling scheme  600  that can be used to accurately determine wind angle and wind speed relative to a vehicle. Modifications, additions, or omissions may be made to port labeling scheme  600  depicted in  FIG. 6 . Port labeling scheme  600  may include more, fewer, or other components. For example, probe  130   a  and/or probe  130   b  of port labeling scheme  600  may have more or less than five facets (e.g., three, four, or six facets). As another example, each probe  130  of port labeling scheme  600  may have more or less than four pressure ports. 
     Although  FIG. 6  illustrates a particular number of probes  130  within port labeling scheme  600 , this disclosure contemplates any suitable number of probes  130  within port labeling scheme  600  that can be used to accurately determine wind angle and wind speed relative to a vehicle. For example, port labeling scheme  600  may be used for an aerodynamic vehicle such that a single probe  130   a  with pressure ports on all facets may be used to accurately determine wind angle and wind speed relative to the vehicle over a full 360 degrees. 
       FIGS. 7A and 7B  illustrate a method  700  for determining wind velocity in accordance with the port labeling scheme of  FIG. 6 .  FIGS. 7A and 7B  may be used by system  100  of  FIG. 1  to determine wind velocity relative to locomotive  110 . Method  700  starts at step  705 . At step  710 , a controller (e.g., controller  140  of  FIG. 1 ) determines air pressures associated with facets of a first probe. The controller determines a first facet pressure p 1a , a second facet pressure p 2a , and a third facet pressure p 1a  associated with a port of a first facet, a port of a second facet, and a port of a third facet, respectively, of the first probe (e.g., ports  1   a,    2   a,  and  3   a,  respectively, of probe  130   a  of  FIG. 6 ). The controller further determines a reference pressure p 4a  associated with a port at an end of the first probe (e.g., port  4   a  of probe  130   a  of  FIG. 6 ). 
     At step  715 , the controller determines air pressures associated with facets of a second probe. The controller determines a first facet pressure p 1b , a second facet pressure p 2b , and a third facet pressure p 3b  associated with a port of a first facet, a port of a second facet, and a port of a third facet, respectively, of the second probe (e.g., ports  1   b,    2   b,  and  3   b , respectively, of probe  130   b  of  FIG. 6 ). The controller further determines a reference pressure p 4b  associated with a port at an end of the second probe (e.g., port  4   b  of probe  130   b  of  FIG. 6 ). 
     At step  720 , the controller determines pressure differentials between each facet pressure and the reference pressure associated with the first probe. Pressure differentials are calculated by taking a difference between values associated with two pressures. For the first probe, the controller determines a first reference differential (p 1a −p 4a ) between first facet pressure p 1a  and reference pressure p 4a  associated with the first probe, a second reference differential (p 2a −p 4a ) between the second facet pressure p 2a  and the reference pressure p 4a  associated with the first probe, and a third reference differential (p 3a −p 4a ) between the third facet pressure p 3a  and the reference pressure p 4a  associated with the first probe. 
     At step  725 , the controller determines pressure differentials between each facet pressure and the reference pressure associated with the second probe. The controller determines a first reference differential (p 1b −p 4b ) between the first facet pressure p 1b  and the reference pressure p 4b  associated with the second probe, a second reference differential (p 2b −p 4b ) between the second facet pressure p 2b  and the reference pressure p 4b  associated with the second probe, and a third reference differential (p 3b −p 4b ) between the third facet pressure p 3b  and the reference pressure p 4b  associated with the second probe. Method  700  then advances to step  730 . 
     At step  730 , the controller compares a facet pressure of the first probe to a facet pressure of the second probe to determine whether to use pressure differentials associated with the first probe or the second probe to calculate wind velocity. In certain embodiments, the probe that is not selected for use in determining wind velocity may be located in a separation zone, whereas the selected probe may be located outside of the separation zone and may therefore more accurately determine wind velocity. The controller determines a pressure differential (p 2b −p 2a ) between second facet pressure p 2a  of the first probe and second facet pressure p 2b  of the second probe. Method  700  then advances to step  735 . 
     At step  735 , the controller determines whether the pressure differential is greater than zero ((p 2b −p 2a )&gt;0). If the pressure differential is greater than zero, method  700  advances from step  735  moves to step  740 , where the controller selects the second probe and uses pressures associated with the second probe to determine wind velocity. If the pressure differential is not greater than zero at step  735 , then the controller advances to step  745 , where the controller selects the first probe and uses pressures associated with the first probe to determine wind velocity. Method  700  advances from step  740  and step  745  to step  750 . 
     At step  750 , the controller determines whether the first reference differential is greater than the second reference differential of the selected probe ((p 1s −p 4s )&gt;(p 2s −p 4s )). The selected probe represents either the first probe or the second probe selected in step  740  or step  745  above. If the first reference differential is greater than the second reference differential of the selected probe, then method  700  advances from step  750  to step  755 , where the controller determines a first rotational differential (p 1s −p 2s ) between the first facet pressure p 1a  and the second facet pressure p 2a  of the selected probe. At step  760 , the controller determines an angular coefficient k a  by dividing the first reference differential by the first rotational differential ((p 1s −p 2s )/(p 1s −p 4s )). Angular coefficient k a  is functionally related to the wind angle such that the wind angle is f(k a ). The function is relatively insensitive to wind speed. The relationship of k a  to the wind angle may be irregular and a curve fit may be employed. The process of finding the curve fit will id determined during a calibration process. 
     After determining the wind angle at step  760 , method  700  advances to step  765 , where the controller calculates wind velocity V w  relative to a vehicle (e.g., locomotive  110  of  FIG. 1 ) using the following formula: V w =*sqrt((p 1s −p 4s )/ρ. Value K v  represents a velocity calibration coefficient that is determined as a function of the wind angle. The functional relationship is determined by the calibration process. Value ρ represents air density that is determined based on the atmospheric air pressure and a temperature. The atmospheric air pressure and temperature are associated with the vehicle and may be determined using one or more components (e.g., an atmospheric pressure device and a temperature sensor) of the communication system of  FIG. 8  discussed below. Method  700  advances from step  765  to step  798 , where method  700  ends. 
     At step  750 , if the controller determines that the first reference differential is not greater than the second reference differential of the selected probe, then method  700  advances from step  750  to step  770 , where the controller determines whether the second reference differential is greater than the third reference differential of the selected probe (e.g., (p 2a −p 4a )&gt;(p 3a −p 4a )). If the second reference differential is greater than the third reference differential of the selected probe, then the controller advances from step  770  to step  775 , where the controller determines a second rotational differential (e.g., p 1s −p 3s ) between the first facet pressure (e.g., p 1a ) and the third facet pressure (e.g., p 3a ) of the selected probe. The controller may determine a third rotational differential (e.g., p 2s −p 3s ) between the second facet pressure (e.g., p 2a ) and the third facet pressure (e.g., p 3a ) of the selected probe. Method  700  then advances to step  780 . 
     At step  780 , the controller determines angular coefficient k a  by dividing the second reference differential of the selected probe by the second rotational differential (p 1s −p 3s )/p 2s −p 4s ). In certain embodiments, the controller may determine angular coefficient k a  by dividing the second reference differential of the selected probe by the third rotational differential (p 2s −p 3s )/p 2s −p 4s ). The selection of whether to use the second or third rotational differential at step  780  may be arbitrary. Method  700  then advances from step  780  to step  785 , where the controller calculates wind velocity V w  using the following formula: V w =K v *sqrt((p 2s −p 4s )/ρ. Method  700  then advances from step  785  to step  798 , where method  700  ends. 
     At step  770 , if the controller determines that the second reference differential is not greater than the third reference differential of the selected probe (e.g., (p 2a −p 4a )&gt;(p 3a −p 4a )), then the controller advances from step  770  to step  790 , where the controller determines a fourth rotational differential (e.g., p 3s −p 2s ) between the third facet pressure (e.g., p 3s ) and the second facet pressure (e.g., p 2s ) of the selected probe. Method  700  then advances to step  795 . 
     At step  795 , the controller determines angular coefficient k a  by dividing the third reference differential of the selected probe by the fourth rotational differential (p 3s −p 2s )/p 3s −p 4s ). Method  700  then advances from step  795  to step  796 , where the controller calculates wind velocity V w  using the following formula: V w =K v *sqrt((p 2s −p 4s )/ρ. Method  700  then advances from step  796  to step  798 , where method  700  ends. 
     As such, method  700  compares pressure differentials between each facet pressure and a reference pressure of a probe to determine an approximate wind direction. These pressure differentials are called reference differentials. A rotational differential, which is a pressure differential between various facet pressures, is divided by the selected reference differential to determine the angular coefficient. The angular coefficient is functionally related to the wind angle. The wind angle is in turn functionally related to the velocity calibration coefficient, which is used to determine wind velocity. The wind velocity is relative to the vehicle upon which the probe is attached. 
     Each probe is calibrated prior to determining wind velocity. One or more facets of each probe may be calibrated separately over a predetermined wind angle range. For example, facets  1   a,    2   a,  and  3   a  of probe  130   a  of  FIG. 6  may be calibrated to cover a range of 0 degrees to 180 degrees of wind angle. Each probe is inserted into a wind tunnel and rotated relative to the flow direction. Probe calibration is performed at one or more wind tunnel velocities (e.g., 50 miles per hour). Pressure differentials are read for all test points prior to processing. Calibration wind velocities are selected in relation to one or more purposes of the system. For example, if the purpose of the system is to prevent wind induced tip-overs of a railroad car, then the calibration may be performed at the lowest wind speed capable of tipping an empty railroad car. 
     When all data are taken, an analyst calibrates the data. Data received from the wind tunnel system are used to associate the known wind angles with measured pressure differentials for each facet with a port. The calibration of each face extends a certain amount (e.g., one point) beyond the determined limits. Each facet with a port is calibrated separately. Each calibration is a curve fit of the parameters calculated from data taken in the wind tunnel. A human (e.g., an analyst) or a machine (e.g., a processor) may calibrate the wind tunnel data. 
     The relative wind angle and wind speed measured directly by the probe will differ from the actual relative wind angle and direction due to the presence of the body of the vehicle (e.g., the locomotive body.) A correlation between measured wind speed and wind direction (i.e., wind speed and wind direction at the probe location) versus actual relative wind speed and direction (i.e., wind speed and direction relative to the vehicle as a whole) is determined. The preliminary body correction may be determined using a CFD model, one or more lookup tables, etc. The preliminary body correction may be different for each vehicle type and each probe position. 
     The method for determining the preliminary body correction may be tested using a specially instrumented test vehicle (e.g., locomotive) to validate and/or improve the preliminary body correction. This correction may then be considered valid for every vehicle of that specific model unless probe locations change. 
     Modifications, additions, or omissions may be made to method  700  depicted in  FIGS. 7A and 7B . For example, method  700  may determine facet pressures for more or less than two probes. As another example, method  700  may determine more or less than three facet pressures and one reference pressure for each probe. As still another example, method  700  may modify step  730  to determine pressure differential (p 1b −p 1a ) in place of or in addition to (p 2b −p 2a ). Method  700  may include more, fewer, or other steps. For example, step  710  and step  715  may be eliminated such that the controller determines differential pressures without determining individual facet pressures. Steps may be performed in parallel or in any suitable order. While discussed as specific components completing the steps of method  700 , any suitable component may perform any step of method  700 . 
       FIG. 8  illustrates a communications system  800  that may be used by system  100  of  FIG. 1 . Communications system  800  includes probe  130   a,  probe  130   b,  controller  140 , pressure lines  810 , transducers  820 , a data acquisition system  840 , a processor  850 , atmospheric pressure device  860 , a temperature device  862 , a compass  864 , a Global Positioning System (GPS) device  866 , a locomotive computer  870 , a display  880 , and a network  890 . 
     Probe  130   a  and probe  130   b,  which are described above in  FIG. 1 , are coupled to a vehicle (e.g., locomotive  110  of  FIG. 1 ) and used to measure wind velocity relative to the vehicle. Probe  130   a  directly outputs four pressures associated with ports  1   a,    2   a,    3   a,  and  4   a  of probe  130   a.  Probe  130   b  directly outputs four pressures associated with ports  1   b,    2   b,    3   b,  and  4   b  of probe  130   b.  Controller  140 , which is described above in  FIG. 1 , may include transducers  820 , data acquisition system  840 , and processor  850 . 
     Pressure lines  810  include four pressure lines  1   a,    2   a,    3   a,  and  4   a  coupled (e.g., hard wired) to probe  130   a  and four pressure lines  1   b,    2   b,    3   b,  and  4   b  coupled (e.g., hard wired) to probe  130   b.  Pressure lines  1   a,    2   a,    3   a,  and  4   a  are routed from ports  1   a,    2   a,    3   a,  and  4   a,  respectively, of probe  130   a  to transducers  820 . Pressure lines  1   b,    2   b,    3   b,  and  4   b  are routed from ports  1   b,    2   b,    3   b,  and  4   b,  respectively, of probe  130   b  to transducers  820 . Pressure lines  810  may be routed through a base of each probe  130   a  and  130   b  and through a hole in the roof of the vehicle (e.g., locomotive  110  of  FIG. 1 ). In certain embodiments, pressure lines  810  may be routed through openings (e.g., windows and/or vents) of the vehicle. 
     Pressure lines  810  may be plumbed into a set of eleven transducers  820 . Transducers  820  of communications system  800  are instruments that measure differential pressure. Transducers  820  may be differential pressure transducers, gauges, sensors, differential pressure transmitters, capacitive pressure transducers, digital output pressure transducers, voltage/current output pressure transducers, a combination thereof, and/or any other suitable device for measuring differential pressure. Transducers  820  may sense a difference in pressure between two ports of probes  130   a  and/or  130   b  and generate an output signal. 
     Transducers  820  include the following eleven transducers:  821 ,  822 ,  823 ,  824 ,  825 ,  826 ,  827 ,  828 ,  829 ,  830 , and  831 . Transducer  821  measures a differential pressure (e.g., first reference differential (p 1a −p 4a ) of  FIG. 7A ) between ports  1   a  and  4   a  of probe  130   a ; transducer  822  measures a differential pressure (e.g., rotational differential (p 1s −p 2s ) of  FIG. 7A ) between ports  1   a  and  2   a  of probe  130   a;  transducer  823  measures differential pressure (e.g., second reference differential (p 2a −p 4a ) of  FIG. 7A ) between ports  2   a  and  4   a  of probe  130   a;  transducer  824  measures differential pressure (e.g., rotational differential (p 2s −p 3s ) of  FIG. 7B ) between ports  2   a  and  3   a  of probe  130   a;  transducer  825  measures differential pressure (e.g., third reference differential (p 1a −p 4a ) of  FIG. 7B ) between ports  3   a  and  4   a  of probe  130   a;  transducer  826  measures differential pressure (e.g., first reference differential (p 1b −p 4b ) of  FIG. 7A ) between ports  1   b  and  4   b  of probe  130   b;  transducer  827  measures differential pressure (e.g., rotational differential (p 1s −p 2s ) of  FIG. 7A ) between ports  1   b  and  2   b  of probe  130   b;  transducer  828  measures differential pressure (e.g., second reference differential (p 2b −p 4b ) of  FIG. 7A ) between ports  2   b  and  4   b  of probe  130   b;  transducer  829  measures differential pressure (e.g., rotational differential (p 2s −p 3s ) of  FIG. 7B ) between ports  2   b  and  3   b  of probe  130   b;  transducer  830  measures differential pressure (e.g., third reference differential (p 3b −p 4b ) of  FIG. 7A ) between ports  3   b  and  4   b  of probe  130   b;  and transducer  831  measures differential pressure (e.g., pressure differential (p 2b −p 2a ) of  FIG. 7A ) between ports  2   a  and  2   b  of probe  130   a  and probe  130   b.    
     Eight pressure lines (i.e., pressure lines  1   a,    2   a,    3   a,  and  4   a  of probe  130   a  and pressure lines  1   b,    2   b,    3   b,  and  4   b  of probe  130   b ) couple ports  1   a,    2   a,    3   a,  and  4   a  of probe  130   a  and ports  1   b,    2   b,    3   b,  and  4   b  of probe  130   b  to eleven transducers  820  (i.e., transducers  821  through  831 .) Pressure line  1   a  is coupled to port  1   a  of probe  130   a  and transducers  821  and  822 . Pressure line  2   a  is coupled to port  2   a  and transducers  822 ,  823 ,  824 , and  831 . Pressure line  3   a  is coupled to port  3   a  of probe  130   a  and transducers  824  and  825 . Pressure line  4   a  is coupled to port  4   a  and transducers  821 ,  823 , and  825 . Pressure line  1   b  is coupled to port  1   b  of probe  130   b  and transducers  826  and  827 . Pressure line  2   b  is coupled to port  2   b  and transducers  827 ,  828 ,  829 , and  831 . Pressure line  3   b  is coupled to port  3   b  of probe  130   a  and transducers  829  and  830 . Pressure line  4   b  is coupled to port  4   b  and transducers  826 ,  828 , and  830 . 
     Each transducer  820  is coupled to a data acquisition system  840 . Data acquisition system  840  is a system that samples one or more components of communication system  800 . Data acquisition system  840  may convert one or more signals received from one or more components of communication system  800  to one or more digital signals. Data acquisition system  840  may sample one or more transducers  820 , atmospheric pressure device  860 , temperature device  862 , compass  864 , GPS  866 , a combination thereof, or any other component of communication system  800 . Data acquisition system  840  may receive signals from one or more components of a vehicle (e.g., locomotive  110  of  FIG. 1 ) such as track speed and curve information. Data acquisition system  800  may convert the received signals to digital signals. These digital signals may be processed by processor  850  to calculate wind speed and wind angle relative to the vehicle. The processed data may be presented to an engineer (e.g., a locomotive engineer). The processed data may be available for input into electronics associated with the vehicle. 
     Data acquisition system  840  is coupled to processor  850 . Processor  850  controls certain operations of communications system  800  by processing information received from one or more components (e.g., transducers  820 ) of communications system  800 . Processor  850  communicatively couples to one or more components of system  800 . Processor  850  may include any hardware and/or software that operates to control and process information. Processor  850  may be a programmable logic device, a microcontroller, a microprocessor, any suitable processing device, or any suitable combination of the preceding. Processor  850  may be included in controller  140  of communication system  800 . Alternatively, processor  850  may be located externally to controller  140 , such as in a cloud computing environment. Processor  850  may be located in any location suitable for processor  850  to communicate with one or more components of communications system  800 . 
     Atmospheric pressure device  860  is a device used to measure atmospheric pressure. Atmospheric pressure device  860  may be an electronic instrument that stores atmospheric pressure on a computer. Atmospheric pressure device  860  may be a barometer (e.g., a mercury or aneroid barometer), a barometric sensor (e.g., a barometric air pressure sensor), a manometer, a combination of the preceding, or the like. Atmospheric pressure device  860  may be located internally or externally to controller  140 . Atmospheric pressure device  860  may be coupled to the vehicle associated with communication system  800 . 
     Temperature device  862  is a device used to measure outside temperature. Temperature device  862  may be a temperature sensor (e.g., a mechanical or an electrical temperature sensor). Temperature device  862  may be located near probe  130   a  and/or  130   b . For example, temperature device  862  may be physically attached to probe  130   a  or probe  130   b.  As another example, temperature device  862  may be located within a predetermined distance (e.g., one foot) of probe  130   a  or probe  130   b.    
     Processor  850  may determine air density using an atmospheric pressure value as measured by atmospheric pressure device  860  and an outside temperature value as measured by temperature device  862 . Air density is equal to atmospheric pressure divided by outside temperature and the gas constant for air. Air density may be calculated using one or more principles of perfect gas law. Air density may be used to determine wind velocity relative to the vehicle associated with communication system  800 , as illustrated in  FIGS. 7A and 7B  above. 
     Compass  864  of communication system  800  is a device used to determine geographic direction. Compass  864  may be a standard magnetic compass, a differential compass, an electronic compass, a magnetometer, a gyrocompass, a combination thereof, or any other suitable device used to determine geographical direction. Compass  864  may include one or more electronic sensors. Compass  864  may be configured to switch to a differential mode when compass  864  reaches a predetermined speed. In differential mode, compass  864  may use GPS to periodically record the position of compass  864 . Compass  864  may compare positions to determine a direction of a vehicle (e.g., locomotive  110  of  FIG. 1 ) and/or to indicate the current bearing of the vehicle. Compass  864  may be integrated with GPS device  866 . 
     GPS device  866  is a device that receives information from GPS satellites and uses this information to calculate the geographical position of GPS device  866 . GPS device  866  may display the position on a display of GPS device  866 . GPS device  866  may display the position on a map. GPS device  866  may determine one or more directions of a vehicle (e.g., locomotive  110  of  FIG. 1 ) using information from compass  862 . One or more components of system  800  may store time-histories of the readings of GPS device  866  to determine direction. GPS device  866  may be integrated with compass  862 . 
     Locomotive computer  870  is a computer on-board a vehicle (e.g., locomotive  110  of  FIG. 1 ) that performs logical control of the vehicle. Locomotive computer  870  may receive signals (e.g., digital and/or analog inputs) from one or more components (e.g., one or more microprocessors) of the vehicle. Locomotive computer  870  may perform diagnostics, such as checking for abnormalities in the operation of the vehicle. Processor  850  may query locomotive computer  870  to gather the information from one or more databases (e.g., a track database) stored on a network (e.g., a network of a railroad). Locomotive computer  880  is located on-bound the vehicle. Locomotive computer  870  may report information (e.g., a type or location of an actual or potential misfunction) to display  880 . Locomotive computer  880  may include one or more components of the computer of  FIG. 12 . 
     Display  880  is a visual device that visually communicates information to an operator of a vehicle. Display  880  may communicate information including wind direction relative to the vehicle, wind speed relative to the vehicle, potential wind-induced tip-over information, information related to track conditions, alarms, instructions, and the like. Display  880  may communicate information that allows the engineer of the vehicle to make decisions. For example, display  880  may visually display instructions that alert the engineer of a potential tip-over so that the engineer can reduce the speed of the vehicle. 
     One or more components of communications system  800  may be connected by a network  890 . Network  890  may be any type of network that facilitates communication between components of system  800 . One or more portions of network  890  may include Center for Transportation Analysis (CTA) Railroad Network. Although this disclosure shows network  890  as being a particular kind of network, this disclosure contemplates any suitable network. One or more portions of network  890  may include an ad-hoc network, an intranet, an extranet, a virtual private network (VPN), a local area network (LAN), a wireless LAN (WLAN), a wide area network (WAN), a wireless WAN (WWAN), a metropolitan area network (MAN), a portion of the Internet, a portion of the Public Switched Telephone Network (PSTN), a cellular telephone network, a 3G network, a 4G network, a 5G network, a Long Term Evolution (LTE) cellular network, a combination of two or more of these, or other suitable types of networks. One or more portions of network  890  may include one or more access (e.g., mobile access), core, and/or edge networks. Network  890  may be any communications network, such as a private network, a public network, a connection through Internet, a mobile network, a WI-FI network, a Bluetooth network, etc. Network  890  may include one or more network nodes. Network nodes are connection points that can receive, create, store, and/or transmit data throughout network  890 . Network  890  may include cloud computing capabilities. One or more components of system  800  may communicate over network  890 . For example, controller  140  and/or locomotive computer  870  may communicate over network  890  to receive information from one or more databases (e.g., a track database) stored on network  890 . 
     Although  FIG. 8  illustrates a particular arrangement of probes  130 , controller  140 , pressure lines  810 , transducers  820 , data acquisition system  840 , processor  850 , atmospheric pressure device  860 , temperature device  862 , compass  864 , GPS device  866 , locomotive computer  870 , display  880 , and network  890 , this disclosure contemplates any suitable arrangement of probes  130 , controller  140 , pressure lines  810 , transducers  820 , data acquisition system  840 , processor  850 , atmospheric pressure device  860 , temperature device  862 , compass  864 , GPS device  866 , locomotive computer  870 , display  880 , and network  890 . The elements of communication system  800  may be implemented using any suitable combination of hardware, firmware, and software. For example, the elements of communication system  800  may be implemented using one or more components of the computer system of  FIG. 12 . 
     Modifications, additions, or omissions may be made to communications system  800  depicted in  FIG. 8 . Communications system  800  may include more, fewer, or other components. For example, communications system  800  may include more or less than two probes  130 , more or less than three ports per probe  130 , and/or more or less than eleven transducers  820 . One skilled in the art would recognize that an embodiment utilizing a different number of probes and/or ports than illustrated in communication system  800  of  FIG. 8  may change the number of pressure lines  810  and/or transducers  820 . As another example, compass  864  and GPS device  866  may be a single device. 
       FIGS. 9A-9F  show CFD simulations used to investigate certain components of system  100  of  FIG. 1 .  FIG. 9A  shows a CFD model domain used to investigate components of system  100  of  FIG. 1  and  FIG. 9B  shows a train used in the CFD model domain of  FIG. 9A .  FIG. 9C  shows a plan view of a simulated airflow around the train of  FIG. 9B ,  FIG. 9D  shows a front view of a simulated airflow around the train of  FIG. 9B , and  FIG. 9E  shows a perspective view of a simulated airflow around the train of  FIG. 9B .  FIG. 9F  shows a top view of a simulated airflow around a probe of  FIG. 9E . 
       FIG. 9A  illustrates a CFD model domain  900  used to investigate system  100  of  FIG. 1 . Specifically, CFD domain  900  illustrates the modeling parameters used to simulate airflow around an object. CFD domain  900  is a volume in which an airflow takes place. CFD domain  900  may be created on any suitable computing device (e.g., a desktop computer, a laptop computer, a smartphone, a tablet, etc.) using any suitable CFD software. CFD domain  900  may be constructed around a geometry of a solid object, such as a locomotive, a railroad car, an automobile, a truck, a car, a bus, an aircraft, a shipping vessel, and the like. In the illustrated embodiment of  FIG. 9A , the solid object is train  910 . CFD domain  900  may be constructed by forming a box  920  or any other suitable shape around the geometry such that the object is contained within box  920 . In the illustrated embodiment of  FIG. 9A , box  920  is 360 feet wide, 360 feet long, and 185 feet high (i.e., 185 feet above railroad track  930 ). The flow domain for the external flow analysis may be calculated by subtracting the geometry from the volume of box  920 . In the illustrated embodiment, CFD domain  900  uses 63,000,000 computational cells concentrated around train  910 . 
       FIG. 9B  illustrates train  910  used in CFD domain  900  of  FIG. 9A . Train  910  includes locomotives  110  of  FIG. 1  and railroad cars  930 . Locomotives  110  include locomotive  110   a  and locomotive  110   b.  In the illustrated embodiment, locomotive  110   a  and locomotive  110   b  are each an Electro Motive Division (EMD) SD70M locomotive, which is a type of 4,000 hp six-axle diesel locomotive. Locomotives  110  are situated on a single track  112  having a 3-foot berm with 30-degree slopes. 
       FIG. 9B  shows a wind angle  940  relative to train  910 . As illustrated, a 0-degree wind angle may be applied perpendicular to and toward a front end  114  of train  910  (e.g., front end  114  of locomotive  110   a ) such that the applied wind is parallel to the sides of train  910  and in a direction from front end  114  to rear end  113  of train  910 . A 180-degree wind angle may be applied perpendicular to and toward a rear end  113  of train  910  such that the applied wind is parallel to the sides of train  910  and in a direction from rear end  113  to front end  114  of train  910 . A 90-degree wind angle may be applied perpendicular to a side of train  910 . Wind angle  940  may be applied to train  910  at any angle ranging from zero to 360 degrees. 
       FIG. 9C  illustrates a plan view  950  of a simulated airflow around train  910  of  FIG. 9B  as used in CFD domain  900  of  FIG. 9A .  FIG. 9C  shows an airflow path around train  910 . Train  910  includes locomotives  110  (i.e., locomotives  110   a  and  110   b ) and railroad cars  930 . Locomotives  110  and railroad cars  930  are bluff bodies from an aerodynamic perspective. The simulated wind speed in CFD domain  900  is 50 miles per hour with an angle of 45 degrees relative to a longitudinal axis of train  910 . In the illustrated embodiment of  FIG. 9C , plan view  950  is taken 2.70 meters above railroad tracks  112  of  FIG. 9A . The simulated wind speed in CFD domain  900  generates airflow path-lines  955 . 
     As illustrated by air flow path-lines  955  in  FIG. 9C , air passes around locomotives  110 . The air is unable to remain attached to train  910  and instead slides across the body of each locomotive  110  and each railroad car  930 . Air flow path-lines  950  separate (i.e., detach) from the body of each locomotive  110  and each railroad car  930 . As air flow separates from the body of train  910  and re-attaches at a region further downwind of train  910 , one or more separation zones  970  may form. If a probe (e.g., probe  130  of  FIG. 1 ) sits in separation zone  970 , the probe may be unable to accurately measure wind velocity. One or more probes used to measure wind velocity may be located outside of separation zones  970  under any possible wind angle (i.e., zero to 360 degrees.) Probes may be located outside of one or more separation zones  970  at some wind angles and within one or more separation zones  970  at other wind angles. The locations of probes  130  in  FIG. 1  satisfy the requirements of at least one probe located outside of separations zones  970  by locating first probe  130   a  and second probe  130   b  on opposite sides of locomotive  110 . Each probe  130   a  and  130   b  of  FIG. 1  can measure wind angles over a range of zero to 180 degrees. 
       FIG. 9D  illustrates a front view  960  of a simulated airflow around train  910  of  FIG. 9B  as used in CFD domain  900  of  FIG. 9A . Front view  960  is cut through locomotive  110   a  of train  910 . Specifically, front view  960  is cut through the locations of probes  130   a  and  130   b  attached to locomotive  110  as illustrated in  FIG. 1 . Air flow path-lines  965  are generated in result of a simulated wind speed in CFD domain  900  of  FIG. 9A  of 50 miles per hour with an angle of 45 degrees relative to a longitudinal axis of locomotive  110   a.  This model was taken to investigate the locations of probe  130   a  and probe  130   b  of  FIG. 1 . Based on this model, a determination was made that the probes should be located such that at least one probe penetrates into the air velocity field at every possible wind angle. As previously discussed in  FIG. 3 , all probes should be located within the clearance plate associated with AAR Plate M  310 . 
       FIG. 9E  illustrates a perspective view  970  of a simulated airflow around train  910  of  FIG. 9B  as used in CFD domain  900  of  FIG. 9A . Specifically,  FIG. 9E  shows simulated airflow past a probe (e.g., probe  130   a  of  FIG. 1 ) attached to locomotive  110   a  of train  910 . Air flow path-lines  975  are generated using a simulated wind speed in CFD domain  900  of 50 miles per hour with an angle of 45 degrees relative to a longitudinal axis of locomotives  110 . The applied wind angle of 45 degrees is applied to a first side  630  of locomotive  110   a.  As illustrated in  FIG. 9E , air flow path-lines  975  intersect probe  130   a  and circumvent probe  130   b.  In an embodiment where the wind is applied to a second side of locomotive  110   a  that is opposite first side  630  of locomotive  110   a,  air flow path-lines  975  will intersect probe  130   b  and circumvent probe  130   a.  Thus, in certain embodiments, two probes are used to determine airflow to accurately account for all possible wind flow directions (e.g., wind flow directions from 0 to 360 degrees). 
       FIG. 9F  shows a top view of a simulated airflow around probe  130   a  of  FIG. 9E . Air flow path-lines  985  are generated using a simulated wind speed in CFD domain  900  of  FIG. 9A  of 50 miles per hour with an angle of 45 degrees relative to a longitudinal axis of locomotive  110   a.  As illustrated, air flow path-lines  985  change direction as airflow passes probe  130   a.  The total velocity of the airflow changes as airflow passes probe  130   a.    
     As such,  FIGS. 9A-9F  illustrate simulated airflow around train  910  and probes  130 , which may provide guidance in determining the shape of probes  130 , the placement of probes  130  on a vehicle, and the orientation of probes  130  relative to the vehicle. 
       FIG. 10  illustrates an example system  1010  for determining wind velocity relative to each railroad car of train  910  traversing a curve  1050  of track  112 . System  1010  includes train  910 , track  112 , probes  130 , and controller  140 . Train  910  includes locomotive  110   a,  railroad car  930   a,  and railroad car  930   b.  Probes  130  are located on locomotive  110   a  of train  910 . System  1010  or portions thereof may be associated with an entity, which may include any entity, such as a business, company (e.g., a railway company, a transportation company, etc.), or a government agency (e.g., a department of transportation, a department of public safety, etc.). The elements of system  1010  may be implemented using any suitable combination of hardware, firmware, and software. For example, the elements of system  1010  may be implemented using one or more components of the computer system of  FIG. 12 . 
     Track  112  of system  1010  includes an inner rail  1020  and an outer rail  1030 . A centerline of track  112  is located at a midpoint between inner rail  1020  and outer rail  1030  of track  112 . Track  112  includes curve  1050 . Curve  1050  is a section of track  112  that deviates from being straight along all or some of its length. Radius  1060  of curve  1050  is a distance from a point  1062  along centerline  1040  of curve  1050  to a point  1064  at a center of an imaginary circle  1066  encompassing curve  1050 . Locomotive  110   a,  railroad car  930   a,  and railroad car  930   b  of train  910  traverse curve  1050  of track  112 . 
     As train  910  traverses curve  1050  of track  112 , a heading of each car (i.e., locomotive  110   a,  railroad car  930   a,  and railroad car  930   b ) of train  910  traversing curve  1050  differs with position of each car on curve  1050 . As such, relative wind speed and wind direction for each car also differs with position of each car on curve  1050 . Accurately determining wind speed and wind direction relative to each car on curve  1050  may prevent wind-induced tip-over of one or more cars of train  910 . 
     Wind speed and wind direction relative to railroad car  930   a  and railroad car  930   b  of train  910  may be determined using the wind speed and wind direction relative to locomotive  110   a.  Wind speed and wind direction relative to locomotive  110   a  may be determined using wind pressure values received from probes  130 . Wind speed and wind direction relative to locomotive  110   a  may be determined in accordance with method  700  of  FIG. 7 . Controller  140  may calculate an absolute wind speed and absolute wind direction relative to ground using the following information: wind speed and wind direction relative to locomotive  110   a,  a track speed, and/or a compass (e.g., an electronic compass, a magnetic compass, a differential compass, a magnetometer, a gyrocompass, etc.). For example, controller  140  may receive one or more readings from a compass (e.g., compass  864  of FIG.  8 ) to determine true North direction relative to ground. Controller  140  may then determine absolute wind speed and wind direction relative to the compass reading. Once an orientation of a given car in train  910  is known, wind velocity relative to the given car can be calculated. 
     Controller  140  may receive a track speed from one or more components of train  910  (e.g., locomotive computer  870  of  FIG. 8 ). Track speed is typically measured on standard locomotives. All cars of train  910  will have the same track speed regardless of the heading of each individual car. If the cars of train  910  are still, the relative wind speeds for all cars are the same, although the wind angle is different. If train  910  is moving, then the relative wind velocity vector (based on relative wind speed and direction) is added to the velocity vector (based on ground speed and track direction) of locomotive  110   a  using vector addition to calculate an absolute wind velocity vector. The absolute wind velocity vector is then added, using vector addition, to the velocity vector (which has the same train speed but a different direction) of railroad car  930   a  or  930   b  to determine the relative wind velocity vector for railroad car  930   a  or  930   b,  respectively. 
     Controller  140  of system  1010  may determine wind speed and wind direction relative to railroad car  930   a  and  930   b  of train  910  using a curve-correction method. Controller  140  may determine radius  1060  of curve  1050 , a bend angle  1070  of curve  1050  between a front end and a back end of train  910 , and a length  1080  of train  910 . Train length  1080  is measured along centerline  1040  of track  112  from a front end of locomotive  110   a  to a rear end of railroad car  930   b.  Controller  140  may use radius  1060 , bend angle  1070 , and train length  1080  to calculate a range of wind angles by calculating a relative angle between locomotive  110   a  and the last car of train  910  (i.e., railroad car  930   b ). An interaction between locomotive  110   a  and an electronic map may be utilized to calculate the range of wind angles. The range of wind angles may be overestimated by a predetermined value or percentage since this curve-correction method may only be accurate when entire train  910  is on curve  1050 . 
     Controller  140  may utilize an advanced variation of the curve-correction method described above. The advanced method requires specific geometric track information based on track geometry, a location of locomotive  110   a,  and information associated with train  910 . By calculating a specific orientation of each car of train  910 , wind speed and wind direction may be determined relative to each car of train  910 . Controller  140  may communicate the relative wind speed and direction along with a car type and a car weight for one or more cars of train  910  to a speed restriction system. The speed restriction system may determine advanced predictions of wind-induced tip-over for one or more cars of train  910 . 
     Track information may include geometry of track  112 , a location of locomotive  110   a  on track  112 , a location of railroad car  930   a  on track  112 , and/or a location of railroad care  930   b  on track  112 . Controller  140  may obtain track information from a track database. For example, controller  140  may obtain track information from a track database stored on network  890  of communication system  800  of  FIG. 8 . Controller  140  may determine track information by querying a computer associated with train  910  to collect track information from the track database. Controller  140  may determine track information by storing time-histories of readings from a compass, storing track speed, and integrating headings for each car on train  930 . Controller  140  may determine track information by storing time-histories of GPS data to differentiate heading for each car of train  910 . 
     In operation, controller  140  determines a wind direction and a wind speed relative to locomotive  110   a  using wind pressure measurements from probes  130 . Locomotive  110   a,  railroad car  930   a,  and railroad car  930   b  are located on curve  1050  of track  112 . Controller  140  calculates an absolute wind direction and an absolute wind speed relative to ground using the wind direction and wind speed relative to locomotive  110   a,  a ground speed, and a vehicle direction of locomotive  110   a.  Controller  140  calculates a wind direction and a wind speed relative to railroad car  930   a  and relative to railroad car  930   b  using the absolute wind direction, the absolute wind speed, the ground speed, and a vehicle direction for railroad car  930   b.    
     Although  FIG. 10  illustrates a particular arrangement of track  112 , probes  130 , controller  140 , and train  910 , this disclosure contemplates any suitable arrangement of track  112 , probes  130 , controller  140 , and train  910 . Although  FIG. 10  illustrates a particular number of locomotives  110 , tracks  112 , probes  130 , controllers  140 , trains  910 , and railroad cars  930 , this disclosure contemplates any suitable number of locomotives  110 , tracks  112 , probes  130 , controllers  140 , trains  910 , and railroad cars  930 . For example, train  910  may include more or less than one locomotive  110   a  and/or more or less than two railroad cars  930   a  and  930   b.  One or more components of system  1010  may be implemented using one or more components of the computer system of  FIG. 12 . 
     Modifications, additions, or omissions may be made to system  1010  depicted in  FIG. 10 . System  1010  may include more, fewer, or other components. For example, train  910  of system  1010  may be replaced with any suitable component used for transportation such as one or more automobiles, buses, trucks, aircrafts, shipping vessels, and the like. As another example, track  112  of system  1010  may be any suitable shape. 
       FIG. 11  illustrates an example method  1100  for determining wind velocity for multiple vehicles traversing a curve of a track. Method  110  begins at step  1105 . At step  1110 , a controller (e.g., controller  140  of  FIG. 1 ) determines a first wind direction relative to a first vehicle (e.g., locomotive  110  of  FIG. 1 ). The first vehicle is moving along a curve of a track. At step  1115 , the controller determines a first wind speed relative to the first vehicle. The controller may receive one or more wind pressures from one or more probes coupled to the first vehicle and determine the first wind direction and the first wind speed using the one or more received wind pressures. The controller may determine the first wind direction and the first wind speed using method  700  of  FIGS. 7A and 7B . Method  1100  then advances to step  1120 . 
     At step  1120 , the controller calculates, in real-time, an absolute wind direction relative to ground using the wind direction relative to the first vehicle. At step  1125 , the controller calculates, in real-time, an absolute wind speed relative to ground using the wind speed relative to the first vehicle. The controller may calculate the absolute wind direction and absolute wind speed of the first vehicle using a ground speed and a direction of the first vehicle. The controller may calculate absolute wind direction and absolute wind speed of the first vehicle using one or more readings from a compass onboard the first vehicle. 
     At step  1130 , the controller calculates a second wind direction relative to a second vehicle (e.g., railroad car  930   a  or railroad car  930   b  of  FIG. 10 ) using the absolute wind speed and direction calculated in step  1120  along with a ground speed and direction for the second vehicle. The second vehicle is any vehicle attached to the first vehicle that is moving along the curve of the track. At step  1135 , the controller calculates a second wind speed relative to the second vehicle using the absolute wind speed calculated in step  1125 . The controller may calculate the absolute wind direction and absolute wind speed of the second vehicle using the ground speed and a direction of the second vehicle. 
     The controller may calculate the second wind speed using an orientation of the second vehicle. The orientation of the second vehicle may be calculated using track information such as track geometry, a location of the first vehicle on the track, and a location of the second vehicle on the track. The controller may calculate the second wind speed using a relative angle between the first vehicle and a last vehicle on the track. The controller may calculate the relative angle using an overall length of the connected vehicles, a bend radius of the track, and a bend angle of the track. Method  1100  then advances to step  1140 . 
     At step  1140 , the controller may determine whether the second vehicle has potential for wind-induced tip-over. Controller may determine whether the second vehicle has potential for wind-induced tip-over based on the second wind direction, the second wind speed, vehicle type information for the second vehicle (e.g., a height, width, and/or length of the second vehicle), and/or a weight of the second vehicle. 
     If the controller determines that the second vehicle does not have potential for wind-induced tip-over, method  1100  advances to step  1150 , where method  1100  ends. If the controller determines that the second vehicle has potential for wind-induced tip-over, method  1100  advances to step  1145 , where the controller triggers an alarm. 
     Triggering the alarm may send one or more signals (e.g., a verbal or written message) to an operator of the first vehicle. For example, triggering the alarm may send a message to an operator of a locomotive via a locomotive display (e.g., display  880  of  FIG. 8 ) to decrease the speed of the locomotive. In certain embodiments, triggering the alarm may initiate one or more automated actions (e.g., decreasing the speed of the vehicle and/or activating a siren). Method  1100  then advances from step  1145  to step  1150 , where method  1100  ends. 
     Modifications, additions, or omissions may be made to method  1100  depicted in  FIG. 11 . For example, method  1100  may include calculating the potential tip-over for multiple railroad cars of a train. Method  1100  may include more, fewer, or other steps. Steps may be performed in parallel or in any suitable order. While discussed as specific components completing the steps of method  1100 , any suitable component may perform any step of method  1100 . For example, at step  1140 , a speed restriction system rather than the controller may determine whether the second vehicle has potential for wind-induced tip-over. 
       FIG. 12  shows an example computer system that may be used by the systems and methods described herein. For example, one or more components of system  100  of  FIG. 1  may include one or more interface(s)  1210 , processing circuitry  1220 , memory(ies)  1230 , and/or other suitable element(s). Interface  1210  (receives input, sends output, processes the input and/or output, and/or performs other suitable operation. Interface  1210  may comprise hardware and/or software. 
     Processing circuitry  1220  (e.g., processor  850  of  FIG. 8 ) performs or manages the operations of the component. Processing circuitry  1220  may include hardware and/or software. Examples of a processing circuitry include one or more computers, one or more microprocessors, one or more applications, etc. In certain embodiments, processing circuitry  1220  executes logic (e.g., instructions) to perform actions (e.g., operations), such as generating output from input. The logic executed by processing circuitry  1220  may be encoded in one or more tangible, non-transitory computer readable media (such as memory  1230 ). For example, the logic may comprise a computer program, software, computer executable instructions, and/or instructions capable of being executed by a computer. In particular embodiments, the operations of the embodiments may be performed by one or more computer readable media storing, embodied with, and/or encoded with a computer program and/or having a stored and/or an encoded computer program. 
     Memory  1230  (or memory unit) stores information. Memory  1230  may comprise one or more non-transitory, tangible, computer-readable, and/or computer-executable storage media. Examples of memory  1230  include computer memory (for example, RAM or ROM), mass storage media (for example, a hard disk), removable storage media (for example, a Compact Disk (CD) or a Digital Video Disk (DVD)), database and/or network storage (for example, a server), and/or other computer-readable medium. 
     Although the systems and methods described herein are primarily directed to determining wind direction and/or wind speed relative to a train, the system and methods described herein may be used to determine wind direction and/or wind speed relative to any structure that may be exposed to high winds. For example, the systems and methods described herein may be applied to structures in the HVAC industry, wind turbine farms, sailing vessels, temporary structure for sports facilities, festivals, and/or concerts, and the like. 
     Herein, a computer-readable non-transitory storage medium or media may include one or more semiconductor-based or other integrated circuits (ICs) (such as field-programmable gate arrays (FPGAs) or application-specific ICs (ASICs)), hard disk drives (HDDs), hybrid hard drives (HHDs), optical discs, optical disc drives (ODDs), magneto-optical discs, magneto-optical drives, floppy diskettes, floppy disk drives (FDDs), magnetic tapes, solid-state drives (SSDs), RAM-drives, SECURE DIGITAL cards or drives, any other suitable computer-readable non-transitory storage media, or any suitable combination of two or more of these, where appropriate. A computer-readable non-transitory storage medium may be volatile, non-volatile, or a combination of volatile and non-volatile, where appropriate. 
     Herein, “or” is inclusive and not exclusive, unless expressly indicated otherwise or indicated otherwise by context. Therefore, herein, “A or B” means “A, B, or both,” unless expressly indicated otherwise or indicated otherwise by context. Moreover, “and” is both joint and several, unless expressly indicated otherwise or indicated otherwise by context. Therefore, herein, “A and B” means “A and B, jointly or severally,” unless expressly indicated otherwise or indicated otherwise by context. 
     The scope of this disclosure encompasses all changes, substitutions, variations, alterations, and modifications to the example embodiments described or illustrated herein that a person having ordinary skill in the art would comprehend. The scope of this disclosure is not limited to the example embodiments described or illustrated herein. Moreover, although this disclosure describes and illustrates respective embodiments herein as including particular components, elements, feature, functions, operations, or steps, any of these embodiments may include any combination or permutation of any of the components, elements, features, functions, operations, or steps described or illustrated anywhere herein that a person having ordinary skill in the art would comprehend. Furthermore, reference in the appended claims to an apparatus or system or a component of an apparatus or system being adapted to, arranged to, capable of, configured to, enabled to, operable to, or operative to perform a particular function encompasses that apparatus, system, component, whether or not it or that particular function is activated, turned on, or unlocked, as long as that apparatus, system, or component is so adapted, arranged, capable, configured, enabled, operable, or operative. Additionally, although this disclosure describes or illustrates particular embodiments as providing particular advantages, particular embodiments may provide none, some, or all of these advantages.