Patent Publication Number: US-7716010-B2

Title: System, method and kit for measuring a distance within a railroad system

Description:
BACKGROUND OF THE INVENTION 
   The present invention relates to railroad systems, and more particularly, to a system and method for measuring a distance within a railroad system. In railroad systems, such as those including a locomotive traveling along a pair of rails, for example, various distance parameters should be monitored to ensure proper operation of the railroad system. The monitoring of these distances have varying applications. For example, when a locomotive is reversing toward an object positioned in the reversal direction, the distance between the back end of the locomotive and the object should be monitored to ensure that the locomotive does not make unintended contact with the object. In another application of monitoring distance parameters during the operation of a railroad system, relative distance shifts of the rails during operation of the railroad system may be monitored to guard against possible derailment. 
   As illustrated in  FIG. 1 , in conventional railroad systems, a truck  11  is employed to travel over a pair of rails, and includes a phased array  13  ( FIG. 2 ) adjacent an undersurface of the truck  11  which is contacted against a respective rail  15  as the truck  11  travels over the pair of rails. As shown in  FIG. 3 , the phased array  13  of the truck  11  emits a plurality of radio frequency signals  17 , which subsequently deflect from an imperfection  19  within the rail  15  and are detected by a detection mechanism  21 . Although  FIG. 3  illustrates an imperfection  19  located within one particular location of the rail  15 , the imperfection  19  may be located at any location within the rail  15 . Once the truck  11  has finished traveling over the rail  15 , data supplied from the detection mechanism  21  provides a detailed analysis of imperfections  19  within the rail  15  at each location along the rail  15 . 
   Although conventional railroad systems provide a truck (or similar vehicle) to travel over a pair of rails and provide a detailed analysis of the imperfections within the rail, such railroad systems neither provide an analysis of relative distance shifts of the rails as an indication of possible derailment, nor provide such an analysis under real operating conditions. Thus, it would be advantageous to provide a system for measuring distances related to the locomotive traveling along the rail under real locomotive operating conditions. 
   BRIEF DESCRIPTION OF THE INVENTION 
   One embodiment of the present invention provides a combination of a railroad system and a system for measuring a distance on the railroad system. The combination includes a rail vehicle having a plurality of pairs of wheels, where the plurality of pairs of wheels are in respective contact with a pair of rails. The combination further includes a transducer positioned on an outer surface location of the rail vehicle, where the transducer emits a signal to an object located the distance away from the transducer. The transducer is configured to receive the signal having reflected from the object along the distance to the transducer. Additionally, the combination includes a controller coupled to the transducer to receive transmission and reception data of the signal to determine the distance. 
   Another embodiment of the present invention provides a method for measuring a distance on a railroad system. The method includes providing a rail vehicle including a plurality of pairs of wheels, where the plurality of pairs of wheels are in respective contact with a pair of rails. The method further includes positioning a transducer on an outer surface location of the rail vehicle, and configuring the transducer to emit a signal to an object located the distance away from the transducer. The method further includes configuring the transducer to receive the signal having reflected from the object along the distance to the transducer, and coupling a controller to the transducer to receive transmission and reception data of the signal to determine the distance. 
   A kit for converting a rail vehicle from a first configuration to a second configuration, where the rail vehicle includes a plurality of pairs of wheels in respective contact with a pair of rails. The kit includes a transducer configured to be positioned on an outer surface location of the rail vehicle, to emit a signal to an object located a distance away from the transducer. The transducer is configured to receive the signal having reflected from the object along the distance to the transducer. Additionally, the kit includes a controller configured to be installed within the rail vehicle and coupled to the transducer to receive transmission and reception data of the signal to determine the distance. When the kit is installed in the rail vehicle, the rail vehicle is converted from the first configuration to the second configuration, where the second configuration has a different operational capability than the first configuration. The first configuration includes manually determining the distance, while the second configuration includes automatically determining the distance using the transducer and the controller. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more particular description of the embodiments of the invention briefly described above will be rendered by reference to specific embodiments thereof that are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the embodiments of the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which: 
       FIG. 1  is a rear perspective view of a vehicle used in a conventional system for determining imperfections within a pair of railroad rails; 
       FIG. 2  is a cross-sectional end view of a railroad rail having an imperfection detected by a conventional system for determining imperfections; 
       FIG. 3  is a top plan view of a conventional system for determining imperfections within a pair of railroad rails; 
       FIG. 4  is a cross-sectional end view of an exemplary embodiment of a system for measuring a distance within a railroad system; 
       FIG. 5  is a side plan view of an exemplary embodiment of a system for measuring a distance within a railroad system; 
       FIG. 6  is a spatial diagram of an image of a railroad rail generated with an exemplary embodiment of a system for measuring a distance within a railroad system; 
       FIG. 7  is a spatial diagram of an image of a railroad rail generated with an exemplary embodiment of a system for measuring a distance within a railroad system; 
       FIG. 8  is a spatial diagram along a pair of railroad rails of an exemplary embodiment of a system for measuring a distance within a railroad system utilizing a phased-array of signals from a transducer over the distance; 
       FIG. 9  is an end plan view of a pair of railroad rails of an exemplary embodiment of a system for measuring a distance within a railroad system; 
       FIG. 10  is an end plan view of a pair of railroad rails and a locomotive wheel of an exemplary embodiment of a system for measuring a distance within a railroad system; and 
       FIG. 11  is a flow chart illustrating an exemplary embodiment of a method of measuring a distance within a railroad system. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   In describing particular features of different embodiments of the present invention, number references will be utilized in relation to the figures accompanying the specification. Similar or identical number references in different figures may be utilized to indicate similar or identical components among different embodiments of the present invention. 
     FIGS. 4 and 5  illustrate one embodiment of a system  10  for measuring a distance  12  within a railroad system  14 . In the illustrated embodiment, the railroad system  14  includes a locomotive  16  with a pair wheels  18 , 20  in respective contact with a pair of rails  22 , 24 . As illustrated in  FIG. 4 , each respective rail includes a center vertical beam  56 , 57  coupled to a horizontal rail beam  58 , 59 . However, the system  10  may be utilized in conjunction with any railroad system other than the railroad system  14  illustrated in  FIG. 4 , such as a railroad system without a locomotive or including additional components than those illustrated in  FIG. 4 . 
   During normal operation of the system  10 , the locomotive  16  pair of wheels  18 , 20  are in respective contact with a pair of rails  22 , 24 . Additionally, the locomotive  16  includes a traction motor  17 , which is used to rotate the pair of wheels  18 , 20 , as appreciated by one of skill in the art. The system  10  includes two transducers  26 , 30  positioned on respective outer surface locations  34 , 36  of the locomotive. As illustrated in the exemplary embodiment of  FIGS. 4 and 5 , each transducer  26 , 30  is respectively positioned at respective outer surface locations  34 , 36  corresponding to respective undersurfaces of each side  35 , 37  of the locomotive  16 , and positioned toward a front end (not shown) of the locomotive  16 . Although  FIG. 5  shows a side view of the locomotive  16  from one side  35 , the placement of the transducers are similar on each side  35 , 37  to that placement illustrated in  FIG. 5 . Each transducer  26 , 30  is positioned at the respective undersurface  34 , 36 , above each respective rail  22 , 24 . More particularly, each transducer  26 , 30  is positioned at the respective undersurface  34 , 36  to be aligned with and above an inner edge portion  23 , 25  of the respective rail  22 , 24 , as discussed below. Although  FIG. 4  illustrates a particular placement for each transducer  26 , 30 , the transducers  26 , 30  may be positioned at any location along the outer surface of the locomotive. Additionally, although  FIG. 4  illustrates two transducers  26 , 30 , any number of transducers may be utilized with an embodiment of the present invention, provided that such transducers provide sufficient data to determine the measured distance, as described below. In an exemplary embodiment of the present invention, the outer surface locations, such as the undersurfaces  34 , 36 , where each transducer  26 , 30  are positioned, may be an outer surface with minimal vibration during normal operating conditions of the locomotive. 
   The transducers  26 , 30  are individually configured to emit a plurality of signals  31 , 33  to the respective rails  22 , 24  which are located the distance  12  away from the respective transducer  26 , 30 . In an exemplary embodiment of the system  10 , a transducer  26  may be positioned on an outer portion of a locomotive wheel, and the distance  12  may be the diameter of the locomotive wheel, for example. Additionally, the transducers  26 , 30  are configured to receive the plurality of signals  31 , 33  having reflected from the respective rails  22 , 24  along the distance  12  and back to the transducers  26 , 30 . Additionally, although  FIG. 4  involves determining the distance  12  from the transducer  26 , 30  to the respective rails  22 , 24 , the system  10  may be utilized to determine the distance from the transducer  26 , 30  to any object, other than the rails  22 , 24 , depending on the particular application of the system  10 . The respective transducer  26 , 30  is aligned to direct the respective signals  31 , 33  toward the respective inner edge portion  23 , 25  of each respective rail  22 , 24 . As illustrated in  FIG. 4 , each respective inner edge portion  23 , 25  is positioned a first threshold distance  28  outward from an inner edge  29  of the rail  22 , and a second threshold distance  32  outward from an inner edge  42  of the rail  24 . Additionally, in an exemplary embodiment of the system  10 , the transducer is an ultrasonic transducer, where each signal  31 , 33  is a high frequency pulse having a frequency greater than 25 kHz, for example. However, any transducer, or device to emit and receive a signal that can supply data to the controller for determining the distance may be utilized. 
   Although  FIGS. 4 and 5  illustrate an embodiment in which each transducer  26 , 30  is utilized to determine a distance between the transducer and the respective inner edge portion  23 , 25  of the respective rail  22 , 24 , the transducer  26 , 30  may be positioned adjacent to a back end or front end of the locomotive  16  as the locomotive respectively moves backward or forward, such that the transducer  26 , 30  determines a distance between the back end or front end of the locomotive and an obstruction object in the railway, for example. In this exemplary embodiment of the system  10 , a transducer  26  would be orientated in the direction of travel of the locomotive. 
   As illustrated in  FIGS. 4 and 5 , the system  10  further includes a controller  38  coupled to each respective transducer  26 , 30  to receive transmission and reception data of the respective signals  31 , 33  to determine the distance  12  between each respective transducer  26 , 30  and the respective inner edge portion  23 , 25  of the respective rail  22 , 24 . Each transducer  26 , 30  is aligned with the respective inner edge portion  23 , 25  of the respective rail  22 , 24  when the locomotive is stationary, and, once the locomotive begins to move along the rails, the respective transducer  26 , 30  emits a plurality of signals  31 , 33  along the distance  12  from the respective transducer  26 , 30  in the direction of the respective inner edge portion  23 , 25 . If the horizontal rail beam  58 , 59  of the respective rail  22 , 24  has not outwardly shifted by more than the first and second threshold distances  28 , 32  between the inner edge portion  23 , 25  and the inner edge  29 , 42 , the respective transducer  26 , 30  will receive the reflected signals  31 , 33  from the inner edge portion  23 , 25  and provide this transmission and reception data to the controller  38 . However, if the horizontal rail beam  58 , 59  of the respective rail  22 , 24  has outwardly shifted by more than the respective first threshold distance  28  and second threshold distance  32  between the inner edge portion  23 , 25  and the inner edge  29 , 42 , the signals  31 , 33  will pass the inner edge  29 , 42  and reflect from a surface  39 , 43  below the inner edge portion  23 , 25  to the respective transducer  26 , 30 , and the respective transducer  26 , 30  will provide this transmission and reception data to the controller  38 . In the event that a respective horizontal rail beam  58 , 59  of the respective rail  22 , 24  outwardly shifts by more than the respective first and second threshold distances  28 , 32 , the respective transducer  26 , 30  will provide transmission and reception data to the controller  38  indicative of a distance greater than the transmission and reception data in the absence of such an outward shift. For example, in an exemplary embodiment of the present invention, if the transducers  26 , 30  provide transmission and reception data to the controller  38  which is indicative of a 15 inch distance between the respective transducer  26 , 30  and the horizontal rail beam  58 , 59 , an outward shift of a respective horizontal rail beam  58 , 59  by more than the respective first and second threshold distances  28 , 32  may cause the transmission and reception data provided to the controller  38  to indicate a 20 inch distance between the respective transducer  26 , 30  and the surface  39 , 43 . As illustrated in  FIG. 6 , a control panel  68  may be utilized for shifting a calibrated dimensional image  50  of the rail  22  (and subsequent images) on a display  48 , in addition to inputting parameters, such as a fixed width  46  of a rail  22 , for example, as discussed below. 
   The controller  38  is switchable between a calibration mode  62  ( FIG. 6 ) and a monitoring mode  70  ( FIG. 7 ). The controller  38  is configured to switch into the calibration mode  62  (either manually on an operator control-panel or automatically) prior to the commencement of a trip by the locomotive  16 . As illustrated in  FIG. 6 , upon switching into the calibration mode  62 , the controller  38  includes a display  48 , where the display  48  shows a calibrated dimensional image  50  of the horizontal rail beam  58  based upon transmission and reception data of the signals  31  emitted from and received by the transducer  26 . As illustrated in  FIG. 6 , the display  48  includes a fixed coordinate axis  52 , with a center  53 , or an origin, at the intersection of the fixed coordinate axis  52 . The controller  38  utilizes the transmission and reception data from the transducer  26  to determine each respective distance for each respective signal  31  reflected from the inner edge portion  23  (if the inner edge portion  23  is aligned with the transducer  26 ) or from a surface  39  beneath the horizontal rail beam  58  (if the inner edge portion  23  is misaligned with the transducer  26  caused by a lateral outward shift of the rail  22  by more than the first threshold distance  28 ). Thus, if the controller  38  determines a distance between the transducer  26  and the surface  39 , the calibrated dimensional image  50  will be shifted on the display  48  by the first threshold distance  28  that the rail  22  has shifted. Although  FIG. 6  illustrates the display  48  with a calibrated dimensional image  50  of the horizontal rail beam  58  generated with transmission and reception data from the transducer  26 , a similar dimensional image of the horizontal rail beam  59  would be generated with transmission and reception data from the transducer  30 , also in conjunction with the fixed coordinate axis  52 . 
   During the calibration mode  62 , the transducer  26  is aligned with the inner edge portion  23  so that the signals  31  reflect from the inner edge portion  23  of the horizontal rail beam  58 , and the controller  38  receives transmission and reception data of the distance  12  between the transducer  26  and the inner edge portion  23  of the horizontal rail beam  58 . Upon switching the controller  38  into the calibration mode  62 , a calibrated dimensional image  50  of the rail  22  on the display  48  is aligned with a center portion  60  of the horizontal rail beam  58  positioned at the center  53  of the fixed coordinate axis  52  using the control panel  68  of the display  48 . A fixed width  46  of the rail  22  is input into the control panel  68 , and the controller  38  displays the calibrated dimensional image  50  of the rail  22 , and locates the center portion  60  of the horizontal rail beam  58  on the calibrated dimensional image  50 , based on the inputted fixed width  46  of the rail and the transmission and reception data received from the transducer  26  aligned above the inner edge portion  23 . Thus, the operator of the locomotive  16  switches the controller  38  into the calibration mode  62  using the control panel  68 , prior to commencement of the trip by the locomotive  16 . Upon switching the controller  38  into the calibration mode  62 , the operator manually shifts the relative position of the calibrated dimensional image  50  with the fixed coordinate axis  52  until the center portion  60  of the horizontal rail beam  58  aligns with the center  53  of the fixed coordinate axis  52 . Although  FIG. 6  illustrates a center  53  of the fixed coordinate axis  52  aligned with the calibrated dimensional image  50 , the calibrated dimensional image may be aligned with any fixed location of the fixed coordinate axis  52 . 
   Once the calibrated dimensional image  50  is centered at the center  53  of the fixed coordinate axis  52  of the display  48 , the controller  38  may be switched into a monitoring mode  70 , and this switching may occur manually by the operator using the control panel  68 , or automatically. In the monitoring mode  70 , the controller  38  is configured to activate the transducer  26  to emit signals  31  as the locomotive  16  propels along the track. As the locomotive  16  propels along the track, and the transducer  26  begins the locomotive trip aligned with the inner edge portion  23 , the signals  31  may continue to reflect from the inner edge portion  23 , or a position along the horizontal rail beam  58  between the inner edge  29  and the inner edge portion  23 , for example. However, as discussed above, if the horizontal rail beam  58  outwardly shifts by more than the first threshold distance  28 , the signals  31  will pass by the horizontal rail beam  58  to the surface  39  below the horizontal rail beam  58  and the transducer  26  will provide transmission and reception data to the controller  38  indicative of a longer distance between the transducer  26  and the surface  39 . As illustrated in  FIG. 8 , as the locomotive  16  propels along the track, a first signal  31 A is emitted from the transducer  26  and reflected from a first inner edge portion  23 A at a first location along the rail  22 , where the emission and reflection path of the first signal  31 A is highlighted in  FIG. 8 . When the locomotive  16  subsequently travels along the track, a second signal  31 B is emitted from the transducer  26  and reflected from a second inner edge portion  23 B at a second location along the rail  22 . As illustrated in  FIG. 7 , during the monitoring mode  70 , as the locomotive  16  propels along the track, the controller  38  utilizes the transmission and reception data from the transducer  26  to determine respective distances for each respective signal  31  reflected from the inner edge portion  23  of the horizontal rail beam  58  of the rail  22  (i.e., the inner edge portion  23  is aligned with the transducer  26 ) or a surface  39  below the horizontal rail beam  58  (the inner edge portion  23  is misaligned with the transducer  26  due to lateral outward shift of the horizontal rail beam  58  by more than the first threshold distance  28 ). The subsequent transmission and reception data and resulting distance measurements during the monitoring mode  70  are used to produce a subsequent dimensional image  72  of the rail  22  at a regular time interval or regular distance interval as the locomotive  16  propels along the track. However, the subsequent dimensional image  72  may be produced at non-regular time or distance intervals, for example. 
   As illustrated in  FIG. 7 , for each subsequent transmission and reception data set and dimensional image  72  obtained during the monitoring mode  70 , the controller  38  is configured to determine a rail shift  76  based upon a gap along the dimensional image  72  between the center  53  of the coordinate axis  52  (i.e., center of the horizontal rail beam  58  during the calibration mode  62 ) and the center portion  60  of the horizontal rail beam  58  during the monitoring mode  70 . Thus, the rail shift  76  is an indication of the lateral shift of the center portion  60  of the horizontal rail beam  58 , and thus also an indication of the lateral shift of the inner edge portion  23  of the horizontal rail beam  58 . As further illustrated in  FIG. 7 , the controller  38  is further configured to determine a pair of side rail distances  80 , 82  indicative of a respective lateral shift of an outer edge  40  and an inner edge  29  from the calibrated center of the rail  22  coinciding with the center  53  of the coordinate axis  52 , as determined in the calibration mode  62 . As illustrated in  FIG. 9 , the rail separation  41  of the respective rails  22 , 24  is a fixed amount, and thus is utilized in conjunction with a fixed width  46  of the wheels  18 , 20  to deduce the proper placement of the respective wheels  18 , 20  (i.e., a lateral outward shift of the horizontal rail beam  58 , 59  greater than a safe threshold is not accommodated by the fixed rail separation  41 ). As further illustrated in  FIG. 9 , the side rail distances  80 , 82  between the center portion  60  of the horizontal rail beam  58  and the respective outer edge  40  and inner edge  29  is illustrated. During the monitoring mode  70 , the controller  38  is configured to continuously monitor the rail shift  76  and side rail distances  80 , 82 , and emit an alert signal  88  to an alert indicator  90  ( FIG. 5 ) upon measuring a rail shift  76  and/or a side rail distance  80 , 82  which exceeds the first threshold distance  28 . In an exemplary embodiment, the first threshold distance  28  may be one or two centimeters, for example.  FIG. 10  illustrates an exemplary embodiment in which the horizontal rail beam  58  has outwardly shifted by a rail shift  76  in excess of the first threshold distance  28  between the inner edge portion  23  and the inner edge  29 . Accordingly, the rail shift  76  introduces a gap between the wheel  18  (which did not outwardly shift relative to the horizontal rail beam  58 ) and the inner edge  29 . Although  FIG. 5  illustrates an alert indicator  90  which receives the alert signal  88 , a wireless alert signal may be wirelessly communicated to a remote location, in order to convene a team of specialists to investigate a possible hazardous rail condition. Similarly, such a team of specialists may wirelessly communicate the possible hazardous rail condition to other locomotives that may be in the vicinity of the area. The alert indicator may be an audible indicator or visible indicator to the operator within the control panel, to alert the operator of the dangerous rail condition so that the locomotive may be stopped and/or inspected. Additionally, the alert indicator may be an automatic indicator which automatically activates a braking system of the locomotive. Those elements of the system  10 , including the controller  38 , which is utilized to determine whether a rail shift has exceeded a predetermined threshold may be similarly performed by an algorithm involving equivalent steps to an exemplary method of the present invention. 
     FIG. 11  illustrates an exemplary embodiment of a method  100  for measuring a distance  12  within a railroad system  14 . The railroad system  14  includes a locomotive  16  with a pair of wheels  18 , 20 , where the pair of wheels  18 , 20  are in respective contact with a pair of rails  22 , 24 . The method begins at block  101  by positioning (block  102 ) a respective transducer  26 , 30  on a respective outer surface location  34 , 36  of the locomotive  16 . The method  100  further includes emitting (block  104 ) a signal  31 , 33  from a respective transducer  26 ,  30  to the rails  22 , 24  located the distance  12  away from the transducers  26 , 30 . The method  100  further includes receiving (block  106 ) each signal  31 , 33  with a respective transducer  26 , 30  having reflected from the respective rails  22 , 24  along the distance  12  to the transducers  26 , 30 . The method  100  further includes receiving (block  108 ) transmission and reception data of the signal  31 , 33  with a controller  38  to determine the distance  12 . 
   Another embodiment relates to a kit for converting a rail vehicle from a first configuration to a second configuration. The kit comprises a transducer configured to be positioned on an outer surface location of the rail vehicle. The transducer is configured to emit a signal to an object located a distance from the transducer. The transducer is configured to receive the signal having reflected from the object along the distance to the transducer. The kit also comprises a controller configured to be installed within the rail vehicle and coupled to the transducer to receive transmission and reception data of the signal to determine the distance. When the kit is installed in the rail vehicle, the rail vehicle is converted from the first configuration to the second configuration, the second configuration having a different operational capability than the first configuration. The first configuration comprises manually determining the distance, and the second configuration comprises automatically determining the distance using the transducer and the controller. 
   Based on the foregoing specification, the above-discussed embodiments of the invention may be implemented using computer programming or engineering techniques including computer software, firmware, hardware or any combination or subset thereof, wherein the technical effect is to measure a distance within a railroad system any such resulting program, having computer-readable code means, may be embodied or provided within one or more computer-readable media, thereby making a computer program product, i.e., an article of manufacture, according to the discussed embodiments of the invention. The computer readable media may be, for instance, a fixed (hard) drive, diskette, optical disk, magnetic tape, semiconductor memory such as read-only memory (ROM), etc., or any emitting/receiving medium such as the Internet or other communication network or link. The article of manufacture containing the computer code may be made and/or used by executing the code directly from one medium, by copying the code from one medium to another medium, or by transmitting the code over a network. 
   One skilled in the art of computer science will easily be able to combine the software created as described with appropriate general purpose or special purpose computer hardware, such as a microprocessor, to create a computer system or computer sub-system of the method embodiment of the invention. An apparatus for making, using or selling embodiments of the invention may be one or more processing systems including, but not limited to, a central processing unit (CPU), memory, storage devices, communication links and devices, servers, I/O devices, or any sub-components of one or more processing systems, including software, firmware, hardware or any combination or subset thereof, which embody those discussed embodiments the invention. 
   This written description uses examples to disclose embodiments of the invention, including the best mode, and also to enable any person skilled in the art to make and use the embodiments of the invention. The patentable scope of the embodiments of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.