U.S. patent application number 11/065423 was filed with the patent office on 2005-09-22 for rail car tracking system.
Invention is credited to Ballesty, Daniel Malachi, Hendrickson, Bradley Charles, Kisak, Jeffrey James, Shaffer, Glenn Robert.
Application Number | 20050205719 11/065423 |
Document ID | / |
Family ID | 34910907 |
Filed Date | 2005-09-22 |
United States Patent
Application |
20050205719 |
Kind Code |
A1 |
Hendrickson, Bradley Charles ;
et al. |
September 22, 2005 |
Rail car tracking system
Abstract
A method and system for tracking a rail car having an on-board
communication system including a location determining system and a
transceiver for receiving and transmitting rail car data. The
communication system including a processor responsive to an
executable program for enabling operation of the transceiver to
transmit rail car data during a reporting event and having a memory
for storing data and instructions. The processor memory includes a
remotely addressable software database accessible by the executable
program for establishing a reporting event in response to at least
one of a selected time, a change in geographical location, an
extended time in a geographical location, an approach to a
specified geographical location, a coupling/decoupling of the rail
car with a particular locomotive and a command to report. The rail
car includes an AEI reader attached to the rail car for reading AEI
tags on other rail vehicles passing by the reader, the reader being
in communication with the rail car message system for transmitting
data indicating at least a location of the other rail vehicles.
Inventors: |
Hendrickson, Bradley Charles;
(Erie, PA) ; Ballesty, Daniel Malachi; (Wattsburg,
PA) ; Shaffer, Glenn Robert; (Erie, PA) ;
Kisak, Jeffrey James; (Erie, PA) |
Correspondence
Address: |
BEUSSE BROWNLEE WOLTER MORA & MAIRE, P. A.
390 NORTH ORANGE AVENUE
SUITE 2500
ORLANDO
FL
32801
US
|
Family ID: |
34910907 |
Appl. No.: |
11/065423 |
Filed: |
February 24, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60547513 |
Feb 24, 2004 |
|
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Current U.S.
Class: |
246/122R |
Current CPC
Class: |
B61L 25/025 20130101;
B61L 25/021 20130101; B61L 27/0077 20130101; B61L 2205/04 20130101;
B61L 25/023 20130101; B61L 15/0072 20130101; B61L 15/0027 20130101;
B61L 15/0081 20130101 |
Class at
Publication: |
246/122.00R |
International
Class: |
B61L 023/34 |
Claims
1. A rail car tracking system comprising: rail car location
equipment mounted to a rail car, the equipment including a
transmitter for transmitting rail car location data to a remote
receiver and further including an electronically readable tag
attached to the rail car for identifying the rail car to a wayside
tag reader; and locomotive communication equipment mounted in a
locomotive and adapted for communication with the rail car location
equipment when the rail car and locomotive are coupled into a
common train, the locomotive communication equipment being
operative to identify the coupled rail car and including a
transmitter for transmitting data to the remote receiver, the data
including rail car data so that the required data transmission from
the rail car transmission equipment is reduced.
2. The rail car tracking system of claim 1 and including a LAN for
data transmission between the rail car and the locomotive.
3. The rail car tracking system of claim 2 and including a
plurality of status sensors coupled to the rail car, each of the
sensors providing data to the car location equipment transmitter
for transmission via the LAN to the locomotive transmitter.
4. The rail car system of claim 3 and including locomotive systems
monitoring equipment coupled in communication with the locomotive
communication equipment for transmitting locomotive data to the
remote receiver.
5. The rail car system of claim 4 wherein the remote receiver
includes a rail car tracking interface for receiving data
transmission from the rail car communication equipment, a
locomotive tracking interface for receiving data transmitted from
the locomotive communication equipment, a system interface for
identifying railcars passing the reader and a central processing
unit for extracting data from all the interfaces for identifying
location of a rail car.
6. An integrated rail car tracking system comprising; a plurality
of fixed wayside automatic equipment identification (AEI) readers
spaced at predetermined locations along a railway for reading
identification data from a AEI tags on rail cars passing along the
railway; a locomotive tracking system including an on-board GPS
system for providing data indicative of the location of the
locomotive and a transmitter for transmitting the location data to
a remote receiver; a rail car wireless message system attached to a
rail car for sending periodic messages indicative of the location
of the rail car, the message system including a GPS system for
generating data indicative of rail car location; and a local area
network (LAN) established between the rail car and an associated
locomotive whereby the rail car location data is transmitted to the
locomotive tracking system for transmission to the remote
receiver.
7. The integrated rail car tracking system of claim 6 and including
a remote data processor for processing data received by the remote
receiver and for extracting from the data information identifying
the location, speed and direction of travel of the associated rail
car.
8. The integrated rail car tracking system of claim 7 and including
a plurality of status sensors mounted on the rail car, the sensors
providing status data to the rail car message system for
transmission to the remote receiver.
9. The integrated rail car tracking system of claim 8 wherein the
status sensors include one or more of door opening/closing sensors,
pressure sensors, temperature sensors and cargo identification
sensors.
10. The integrated rail car tracking system of claim 8 and
including programming operable in an on-board processor 28 for
reading time and location from GPS for indicating dwell time
without substantial movement.
11. The integrated rail car tracking system of claim 7 and
including data storage at the remote processor for storing data
representing rail car scheduling, the processor comparing rail car
data to rail car scheduling for providing data indicative of
deviations from scheduling.
12. The integrated rail car tracking system of claim 7 and
including programming means operable in the rail car message system
for transmitting periodic messages to the remote receiver and for
transmitting status change messages to the remote receiver upon
detection of a status change.
13. The integrated rail car tracking system of claim 7 and
including locomotive status sensors mounted in the locomotive and
coupled to the locomotive communication system for providing data
indicative of locomotive status to the remote receiver.
14. The integrated rail car tracking system of claim 12 wherein one
of the status change messages comprises a message indicating
movement across a predetermined geographical boundary.
15. The integrated rail car tracking system 7 and including a rail
car battery saving function for reducing rail car transmissions
when the rail car is coupled to the locomotive.
16. The integrated rail car tracking system of claim 7 and
including a rail car battery saving function for reducing rail car
transmissions when the rail car remains stationary.
17. A method for tracking a rail car having an on-board
communication system including a location determining system and a
transceiver for receiving and transmitting rail car data, the
system including a processor responsive to an executable program
for enabling operation of the transceiver to transmit rail car data
during a reporting event, the method comprising providing a
remotely addressable software database accessible by the executable
program for establishing a reporting event in response to at least
one of a selected time, a change in geographical location, an
extended time in a geographical location, an approach to a
specified geographical location, a coupling/decoupling of the rail
car with a particular locomotive and a command to report.
18. The integrated rail car tracking system of claim 7 and
including an AEI reader attached to the rail car for reading AEI
tags on other rail vehicles passing by the reader, the reader being
in communication with the rail car message system for transmitting
data indicating at least a location of the other rail vehicles.
Description
[0001] This application claims the benefit of U.S. provisional
application No. 60/547,513 filed Feb. 24, 2004.
FIELD OF THE INVENTION
[0002] This invention relates generally to the field of rail
transportation, and more particularly to tracking locations of rail
cars within a rail transportation system.
BACKGROUND OF THE INVENTION
[0003] Railway shippers need to be able to track the location of
rail cars within a rail transportation system. Supply chain
management improvements and heightened security concerns have
increased the need to track and pinpoint rail car locations at all
times, whether the rail car is stationary in a rail yard or siding,
or being moved through the rail system by a locomotive. Currently,
rail cars may be equipped with radio frequency identification
(RFID) tags such as Automatic Equipment Identification (AEI) tags
that may be read by a wayside tag reader positioned at known
locations within the rail system and configured to recognize and
report when an AEI tagged railcar passes. Such reports are known as
Car Location Messages (CLM's). Accordingly, a location and a time
of passage of the rail car may be reported from the wayside tag
reader to a centralized database that may be accessed by shippers
or the railroad companies to track the last reported locations of
their tagged rail cars. However, such an AEI system can only
provide location information of the rail car at the time when the
car passes the reader. Thus, the exact location of a railcar at
times after it has passed an AEI tag reader, such as in an
industrial plant, is not known through the use of the AEI tag
system. Moreover, with only a relatively limited number of AEI tag
readers available, a significant length of track (and thus a large
number of possible railcar locations) may exist between adjacent
AEI tag readers. Rail cars have also been equipped with locating
equipment, such as a global positioning satellite (GPS) receiver,
coupled to an on-board transmitter to transmit rail car location
information to a central site for rail car tracking purposes.
However, as described below, these systems typically transmit a
large body of information in long messages so as to fully identify
the location of the railcars and do so on regularly scheduled timed
intervals, so that battery life has proven to be unacceptably
short. On some trains known as dedicated "unit" trains, train-based
local area networks (LAN's) have also been deployed to link cars in
the train to the train locomotives.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] The invention will be more apparent from the following
description in view of the sole FIGURE that shows a functional
block diagram of an exemplary system for tracking rail cars in a
rail transportation system.
DETAILED DESCRIPTION OF THE INVENTION
[0005] The present invention innovatively integrates information
accumulated from multiple railway IT systems to provide a rail car
tracking system operating on extended life intervals. The present
invention enables a rail car tracking system that provides
location-reporting accuracy that is improved over existing AEI tag
systems that are limited by the spacing between wayside readers.
The present invention also enables a rail car tracking system that
provides high-value information transfer with low on-car power
requirements by utilizing event-driven reporting and reduced
message lengths. In one embodiment, the capabilities of AEI tag
systems, locomotive communication systems and railcar GPS systems
are integrated with railroad train, track and schedule databases to
provide a cost effective and power effective solution to the
problem of rail car tracking.
[0006] In the past, rail cars were not typically equipped with an
independent electrical power generating means to power onboard
electrical equipment. While techniques such as air powered, or axle
rotation-powered generators have been proposed, such systems only
work when the rail car is coupled to a compressed air source, such
as a locomotive, or when the rail car is moving. Consequently,
batteries are typically used as the primary source of power for
rail car onboard electrical equipment. However, batteries, if not
recharged, cannot power equipment indefinitely. Furthermore, the
higher the power usage of the battery, the shorter the life of the
battery. While batteries may be convenient for limited rail car
equipment powering needs, battery maintenance and replacement
increases operating costs for the railway.
[0007] In rail car tracking applications using a GPS receiver and
transmitter, transmission of information from the rail car, and, in
particular, transmission of messages containing relatively large
amounts of information, may quickly deplete a battery, especially
if such messages are transmitted on a relatively frequent periodic
basis. Accordingly, it is desired to reduce the power requirement
needed by onboard rail car electrical equipment, such as rail car
locating equipment, while still providing improved rail car tracing
and reporting capability. The inventors have recognized that by
innovatively combining different rail car tracking techniques and
assimilating railway information acquired from a variety of
pre-existing sources, improved rail car tracking may be achieved by
the inventors unique presentation of more comprehensive tracking
and scheduling information in a single user-friendly form, together
with reduced power consumption by the rail car onboard tracking and
reporting equipment. Advantageously, rail car battery life may be
extended, and battery maintenance and replacement intervals may be
reduced compared to conventional techniques of providing rail car
location information.
[0008] The FIGURE is a functional block diagram of an exemplary
system 10 for tracking rail cars in a rail transportation system.
The system 10 generally includes rail car location/transceiver
equipment 12 forming a wireless message system mounted on a rail
car 22. The rail car location/transceiver equipment 12 may include
a location determination device, such as a GPS receiver 24, a
transceiver 26, a processor 28, and a memory 30 for storing
processor instructions. The rail car 22 may also be equipped with a
sensor suite 32 for sensing operating conditions of the rail car
22, and a power source, such as a battery 34, for powering the
sensor suite 32 and the rail car location/transceiver equipment 12.
The sensor suite 32 may include sensors such as an accelerometer
for detecting movement of the rail car 22, a temperature sensor, a
pressure sensor, a door position sensor, a cargo identification
sensor, and a cargo seal condition sensor. The rail car 22 may also
be equipped with an AEI tag 33 to uniquely identify the car 22 to a
wayside AEI tag reader 36 that the car 22 passes. The AEI tag is
preferably an active tag including a processor that allows the tag
to read as well as being read and to communicate the results of the
reading of external tags such as those on wayside markers or on
other rail vehicles (rail cars and locomotives, for example) to the
equipment 12 so that the location of the external tags can be
communicated to a remote rail system monitoring and tracking
operation. This enables comparison of different AEI data for
determining location of rail assets. The railcar may also sense
attributes of the cargo contained within the railcar. For example,
an RFID reader (not shown) may be in communication with the
processor 28 for sensing RFID tagged cargo in the railcar 22. Such
information may be provided to customers of the railroad via the
shipper interface 56.
[0009] In an aspect of the invention, the rail car
location/transceiver equipment 12 may be in communication with a
rail car tracking interface 16 controlled by a central processor 19
having access to a centralized train and car tracking database 18.
The rail car tracking interface 16 is off-board of the railcar and
remote from the rail car location transceiver equipment 12 as
indicated by dotted line 20. The rail car tracking interface 16 may
include a transceiver for communication to and from one or more
rail cars, a processor, a memory, and a communication interface,
such as a LAN or Internet interface, for communication with the
central processor 19. The rail car location/transceiver equipment
12 may communicate with the rail car tracking interface 16 over a
suitable wireless rail car radio link 14, such as a satellite or
cellular network. The rail car transceiver 26 may be configured for
bidirectional operation so that the rail car 22 may transmit rail
car data and receive instructions, for example, from the rail car
tracking interface 16. Information, such as railcar location data,
speed data, heading data, sensor data, and battery power data, may
be transmitted from the rail car 22 in accordance with programmed
instructions, upon request from the rail car tracking interface 16,
and/or upon occurrence of an exceptional event. In addition, dwell
alert information, indicating, for example, that the rail car has
remained motionless for a certain period of time, may also be
transmitted from the rail car 22 on a periodic basis or upon
request. Dwell alert data may be obtained by the processor 28
monitoring timing and GPS position from GPS 24. In yet another
aspect, "geo-fencing" information, such as a time when the rail car
22 has traversed a predetermined geographic boundary, may be
transmitted by the rail car 22 when the rail car 22 crosses the
this virtual boundary. Accordingly, the configurable geo-fences may
be used to simulate AEI readers by providing CLM messages when the
rail car passes a certain location.
[0010] In an embodiment of invention, the rail car
location/transceiver equipment 12 may be configured to communicate
with a locomotive 38 over a locomotive communication link 40 such
as a wireless local area network (LAN), for example, when the rail
car 22 is connected in a train powered by the locomotive 38. The
locomotive 38 may include locomotive communication equipment 42 for
communicating with the rail car 22 over the LAN, and for
communicating with a locomotive interface 48 over a wireless
locomotive radio link 14. The locomotive communication equipment 42
may sense and report the status of onboard locomotive systems 44.
The locomotive communication equipment 42 may be configured to
transmit locomotive location from various sources such as an AEI
reader and GPS receiver 45, speed, heading, dwell alert
information, geo-fencing information, and train handling
information to the locomotive interface 48. In an aspect of the
invention, locomotive operation indicative of a decoupling maneuver
may be transmitted to the locomotive interface 48 to alert a
possible decoupling of rail cars 22 from a train pulled by the
locomotive 38. The locomotive interface 48 may include a
transceiver for communication with one or more locomotives, a
processor, a memory, and a communication interface, such as a LAN
or Internet interface, for communication with the central processor
19.
[0011] The system 10 may further include a system interface 50 for
receiving other inputs that may be useful for tracking rail cars in
the system 10. The system interface 50 may include input
communication interfaces appropriate for receiving these other
inputs, such as a wireless communications interface, a wide area
network (WAN) interface, or an Internet interface; a processor; a
memory; and an output communication interface; such as a LAN or
Internet interface, for communication with the central processor
19. In an aspect of the invention, the system 10 may be configured
to receive data from one or more AEI readers 36. Through
communication with a track database 52 that contains, for example,
locations of AEI readers 36 throughout a railway system, the system
interface 50, upon receiving an indication of a sensed rail car
from one of the AEI readers, such as over an AEI wireless link 54,
may be configured to provide a location of a rail car 22 at certain
point in time when the rail car 22 passes the reader 36. The
present system 10 may utilize AEI reader data to recognize an
assemblage of rail cars as a train and to associate that train with
one or more locomotives. In this manner, locomotive position data
received from the locomotive interface 48 may be applied to all of
the rail cars in the train to update rail car position information
without the need for any car-specific data transmission.
[0012] The system interface 50 may also include inputs for railroad
(RR) work order information, RR estimated time of arrival (ETA)
information, weather information, train schedule information, track
circuit information and computer aided dispatch (CAD) information.
Such information acquired from various sources may be assimilated
and used to provide more comprehensive data associated with rail
car 22 locations in a single user-friendly presentation and in a
more power efficient manner. In an aspect of the invention, the
rail car tracking interface 16, the locomotive interface 48, the
system interface 50 and the track database 52 may be in
communication with each other and the central processor 19 and
train and car tracking database 18, such as over a suitable
network, such as a LAN or Internet connection, to allow integration
of information from among these sources. The train and car tracking
database 18, or portion of the database 18, may also be provided,
for example, via the central processor 19, to a shipper interface
56 or railroad (RR) company interface 60 that may be accessible by
shippers, such as over a secure communication link, to allow
shippers to locate their rail cars within the railway system.
[0013] The information gathered from the input sources via the
interfaces 16, 48, 50 may be used to provide real-time rail car
location, car speed, car heading, notifications when a car arrives
at a predetermined location, notification when cargo conditions
changes, such as a seal opening or closing, temperature or pressure
readings exceeding predetermined values, and ETA at a destination.
In an embodiment, operating instructions based on input parameters
such as rail car destination, train schedules, and cargo carried by
the rail car 22 and generated by the train and car tracking
database 18 may be provided to a rail car 22 via, for example,
wireless transmission of instructions from the rail car tracking
interface 16. The rail car receives the operating information and
may store the information in memory 30 as processor instructions to
control operation of the rail car location/transceiver equipment 12
to conserve battery power. Such information may be provided to the
rail car 22 at any time, or in response to a change in condition of
the rail car, such as when the rail car is connected to or
disconnected from a train, or in response to changing parameters
within the railway system, such as a change in weather or track
conditions. One may appreciate that if rail car position
information is being updated on the basis of a car-assemblage train
definition and train locomotive position data, it is important for
system 10 to recognize when a rail car is being associated with or
disassociated from a particular train.
[0014] In order to reduce power usage on-board the rail car, the
system 10 may be configured to transmit as little data as possible
from the rail car, while at the same time ensuring that high value
information is transmitted in a timely manner. Data that can be
obtained directly or indirectly from other sources need not be
generated at the railcar (and thus need not be transmitted from the
rail car), such as the example described above of car location
being derived from train location that is reported as locomotive
location. The central processor 19, based on input information
provided by the interfaces 16, 48, 50, and information stored in
the train and car tracking database 18, may generate instructions
for transmission to a rail car 22 for reducing a transmission
frequency and/or amount of information transmitted by the rail car
22 to conserve battery power. Data transmitting frequency may be a
function of variables other than time, such as distance from a
destination, initiation of movement, location, etc. Typically, only
data that is new or revised (or otherwise not available from
another source) would be transmitted. An innovative method of
achieving reduced power consumption by a rail car may include
limiting transmission of information to occurrences of an exception
to an expected operation profile, instead of transmitting, at a
fixed periodic rate, information that may not be changing or is not
varying within a predetermined range of desired values. The rail
car location/transceiver equipment 12 and sensor suite 32 may be
configured to remain in a minimum power state until an exception
occurs, such as when a condition detected by a sensor changes or
exceeds a predetermined value. The processor 28 may then transmit
an exception signal to the rail car tracking interface 16. Such an
exception signal may be formatted as a message having a limited
length to contain only the minimum amount of information needed to
report the exception condition. In an aspect of the invention, the
rail car tracking interface 16 may be configured to send a response
signal to the rail car 22 from which an exception signal was
received. The response signal may contain new instructions for the
rail car location/transceiver equipment 12 based on the nature of
the exception, or the response may contain an acknowledgement
indication verifying that the exception signal was received. The
rail car location/transceiver equipment 12 may be configured to
transmit exception signals at a periodic rate when an exception
occurs until a response is received from the rail car tracking
interface 16 to verify that the exception signal is received.
[0015] The processor 28 may be programmed with instructions
allowing it to recognize conditions indicative of not being
attached to a locomotive. When a rail car is on a siding and is not
moving, processor 28 may be programmed to report that it is parked
and then to provide no further report until it is moved, or until
it is moved past a known location such as an AEI location. During
such dormant periods, programmed messages may be prepared via the
system interface 50 and may be stored in a virtual in-box for the
rail car. The rail car equipment may be programmed to awaken
periodically to check its in-box for messages, such as revised
reporting schedule instructions.
[0016] For example, if a temperature exceeds a predetermined value,
an exception signal reporting a sensed temperature extreme may be
transmitted to the rail car tracking interface 16 and reported to
the train and car tracking database 18. If the rail car 22 has
onboard refrigeration capability, the train and car tracking data
base 18 may recognize this and provide an instruction to be sent to
the rail car 22 via the rail car tracking interface 16 to remedy
the exception condition, such as by controlling the onboard
refrigeration unit to provide additional cooling. Once an exception
has occurred, exception reporting parameters may be changed, for
example, by providing new parameters via the rail car tracking
interface 16, to more closely monitor the exception condition. In
another example, if a door sensor detects that a door on the rail
car 22 has been opened, an exception signal may be transmitted
reporting an open door condition. Location information may be
provided in the exception signal to allow maintenance personnel to
locate the rail car 22 and correct the sensed condition, such as by
closing the open door. In yet another example, if an accelerometer
sensor on the rail car senses a pattern of movement indicative of
decoupling rail cars, an exception signal identifying the
condition, including location information, may be transmitted.
[0017] In yet another aspect, an accelerometer exception signal may
be generated if a change from a moving condition to a stopped
condition, or vice versa, is sensed. For example, if a rail car 22
has been disconnected from a train and left stationary in a siding
or train yard, and the accelerometer detects movement of the rail
car 22, an exception signal, which may include location
information, may be generated to indicate the rail car 22 has
moved. Similarly, if a rail car 22 has been moving, such as in a
train, and a stopped condition is detected, an exception signal,
which may include location information, may be transmitted to
indicate an unexpected stop. In another embodiment, a mercury
switch may be used to sense acceleration or deceleration. Other
exception signals may be generated to report the health of the
tracking equipment onboard the railcar, such as when a low power
battery condition exists, if a GPS link fails, or if any of the
rail car onboard equipment fails or is not operating within desired
specifications. In still another aspect, if a rail car 22 has
remained stationary for a certain amount of time, the rail car
location/transceiver equipment 12 may be scheduled to "wake up"
periodically to identify its location and/or accept new information
from the rail car tracking interface 16.
[0018] In still another aspect of the invention, instead of sending
location data on a fixed periodic basis as such information is
conventionally sent, power conservation on the rail car 22 may be
achieved by limiting frequency of rail car transmissions, such as
location information, depending on a distance from an intended
destination. For example, a shipper may only want to know the
location of a rail car 22 as the car 22 nears its destination. If a
rail car 22 is traveling on a trip of a known distance, such as a
one thousand mile trip, and an average speed of the rail car is
known, such as may be inferred from locomotive information or
estimated as an average speed for the trip based on historical data
and current railway conditions, the rail car 22 may be instructed
to transmit its location when it is projected to be at
predetermined time, such as 10 hours, away from its destination,
seen as a geo-fence, and may increase its frequency of transmitting
location information after reaching this point. The central
processor 19 may perform speed, time and distance calculations to
project when a rail car needs to report its location. The lack of
such an expected may stimulate an inquiry being sent to the rail
car's "in box" to prompt the rail car to report its present
location/condition.
[0019] In another aspect, power conservation on the rail car 22 may
be achieved by limiting frequency of rail car transmissions using
the concept of geo-fences, or electronically bounded areas of
railway operation. For example, an electronic boundary may be
defined around the outskirts of a city to indicate to a train
crossing the boundary that the train has left or entered the
outskirts, depending on its direction of travel. The direction of
travel may be determined from train schedule data or locomotive
data available in the system 10. Direction of travel may also be
provided by heading information developed from GPS data. This
concept may be implemented by defining a geographic location of the
boundary so that when a train having self-locating equipment
traverses the boundary, the train may be configured to recognize
that it has crossed the boundary by correlating its current
location with the defined geographic location of the boundary. For
example, a rail car 22 may be provided with appropriate geo-fence
locations by the rail car tracking interface 16 at the beginning of
a trip, such as when the rail car 22 is coupled to train, based on
the destination of the rail car 22. Then, instead of transmitting
location information on a periodic basis, the rail car 22 may be
instructed to limit sending of location information to an
occurrence of the rail car traversing a geo-fence boundary. For
example, the rail car may compare its current location, such as
derived from received GPS position data, to geo-fence boundary
information stored in memory 30 to determine if the rail car has
crossed a geo-fence boundary, and, if a boundary crossing has
occurred, the rail car 22 may transmit an indication that it has
crossed the boundary.
[0020] Another innovative method of reducing power consumption may
include decreasing a frequency of transmission of data when
location information may be inferred using other means, such as by
using locomotive or AEI position information to infer a rail car
location when the rail car 22 is in a train attached to the
locomotive 38. Typically locomotive information may be provided on
a relatively frequent basis because power consumption by the
locomotive communication equipment 42 is not a concern.
Consequently, when the rail car 22 is attached to a train pulled by
a locomotive 38 that is in communication with the locomotive
interface 48, rail car location information may be inferred from a
locomotive 38 location instead of requiring the rail car to
independently report its location. Furthermore, rail car status
information may be inferred from locomotive action, such as when
locomotive information provided to the locomotive interface 48
indicates that the locomotive is performing make/brake maneuvers,
indicative of decoupling rail cars. If such locomotive maneuvers
are detected, the rails car tracking interface 16 may instruct the
rail car 22 to identify its location to determine if the car 22 has
been decoupled or is still traveling with the train.
[0021] In yet another aspect, the rail car 22 may be monitored to
determine remaining battery life based on past usage by the rail
car location/transceiver equipment 12. For example, remaining
battery life may be modeled based on the number and/or length of
messages transmitted by the rail car location/transceiver equipment
12. If a cumulative number and/or cumulative length of messages
transmitted by the rail car 22 exceeds a predetermined total number
and total length indicating the battery power may soon be
exhausted, the rail car 22 may be instructed to transmit its
location and then refrain from transmitting until the battery 34 is
replaced or recharged. Service personnel may also be alerted at the
same time of the need to replace or recharge the battery onboard
the railcar. The rail car location/transceiver equipment 12 may be
configured to perform this battery monitoring function, or the
function may be performed remotely, such as by the rail car
tracking interface 16, based on the number and length of
transmissions received for the rail car 22.
[0022] In yet another embodiment, the locomotive may be equipped
with an AEI reader and may function as a roaming locator of rail
cars. The locomotive may be configured to identify cars within its
train. The locomotive may also be configured to locate other cars
that it passes, such as cars stationary on a siding, by reading the
AEI tags of those cars and by providing the corresponding tag and
location information to the locomotive interface 28 for processing
by the central processor 19.
[0023] While the preferred embodiments of the present invention
have been shown and described herein, it will be obvious that such
embodiments are provided by way of example only. Numerous
variations, changes and substitutions will occur to those of skill
in the art without departing from the invention herein.
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