Field of the Invention
The present invention relates to a device for monitoring railway trackside color-light
signals and position and direction of trains and like transits and method thereof.
Background Art
It has been seen that there are many proposals in the past regarding the issue of train
collision avoidance. In these existing system, which uses global positioning system
(GPS) to exchange the Train coordinates between the two moving trains and the moment
it detects the trains on the same line in the block section, it applies the brakes to the train.
The main issue involved is inaccuracies in the calculation of the position of the trains
moving head-on. It is a commonly known fact that GPS accuracies are of the order of
15 meters and for DGPS +1-5 meters. When there are two running tracks in the block
section, the system cannot confirm appositively that the two trains are moving on the
same line of the block section. Physically, if it is done manually, it can cause
malfunctions due to likelihood of human errors. Since the system cannot differentiate
between the moving trains in two lines in the same block section, its system of issuing of
alarm for head-on collision on double line track remains questionable. The role of GPS
also stands to question when it is required to differentiate a train diversion in the adjacent
track, which is hardly two-three meter away. This system seems to work partially for the
single line block sections through GPS coordinate exchange; but elsewhere there are
cases of distinct ambiguity.
The problem to be addressed is the communication of the status of train signal, direction
and position of trains on the track to the locomotive driver even beyond the visible range.
The problem is overcome by providing a wireless device having a signaling unit capable
of monitoring electrical status of the Railway track side color-light signals and a radar
system to beam microwaves across railway tracks located on both sides of said signal to
gather information on position and direction of the trains on the tracks and wirelessly
transmit the information. The driver in the locomotive has appropriately tuned receiving
unit to receive the signals and information transmitted by the signaling unit and the radar
system respectively. Thus, the receiving unit placed inside the locomotive is able to
detect and represent the signal status to the driver along with other required parameters
without any obstruction and reliably even though the Locomotive driver has not come in
the visible line of sight with the Railway track side color light signals.
Disclosure of the Invention
It is the object of the device to reduce the problems of train collision and provide solution
to pre-detection of head-on and rear end collision between the trains. The device
according to an embodiment of the present invention is interfaced onboard to a Home
railway signal, which is located just at the entry point of the station. It is after this signal
the tracks begin to diverge or merge between each other as per requirement. The device
when interfaced to this signal starts reading the color-light signal status and its
microwave radar unit mounted on the signal is beamed across the tracks in a manner such
that microwaves cross both the parallel tracks in a slanting position and in the both
directions. When the train entering a station is met by the home signal, the device
interrogates with a similar tuned device mounted in the locomotive. The signal status is
thus provided to the driver cab through RF link. The onboard locomotive device monitors
the signal aspects and train speed through its onboard GPS and if wrong action is taken
by the driver that is if crossing a red signal at home, the system through GPS odometer
and radar unit could either alert the driver or cause emergency brake application on the
locomotive. When the signal is green and the train has just crossed the signal, the radar
detects its position on track and gives necessary feedback to the locomotive driver. The
device mounted on the home signal is programmed to detect the right direction of the
traffic flow under normal conditions. In normal working trains coming from the station
are required to follow correctly either Up or Down tracks. In case of system
malfunctioning, e.g. due to wrong interlocking or improper route setting, the radar
interrogates the device in the locomotive which is already programmed for directions, i.e.
Up or Down with respect to its present placement on the track. In the event of mismatch,
the system calls for emergency braking on the locomotive .The device also has an
optional diagnostic and override control system in the form of data logger located within
the station premises. This unit is interfaced to the signaling system as a feedback unit to
detect the signal aspects being relayed to the various station signals. This unit has pre-fed
GPS codes of the physical position of the Railway color light signals that are placed in
the station and yard premises. With this additional information, it is able to wirelessly
transmit status aspects along with the GPS coordinates to the locomotive driver for
proper identification of signals.
It is another object of the invention to provide a device to check the position of the train
with respect to the home signal or any convenient signal and allocated direction of
movement in the two tracks that is up for one direction and down for the other, such that
any wrong movement does not take place as the radar knows where the tracks are
physically placed.
It is another object of the invention to provide a device to transmit and check the position
of the locomotive around the physical color light signaling area and get a feedback from
the locomotive from a wireless device placed inside the railway station.
It is yet another objective of the invention to provide the locomotive driver the
information about the signal and such that the signal disobedience is taken care of.
It is yet another objective of the invention to provide the locomotive driver the
information about the signal status at the other side of the station in order to calculate the
occupancy of the track and supervise any wrong allocation.
With the above and other objectives in view, as will hereinafter appear, various
embodiments of the present invention are described hereunder.
According to an embodiment of the invention, a wireless device for monitoring railway
trackside color-light signals and position and direction of trains is provided which
comprises an electronic signaling unit having a radar system to beam microwaves across
railway tracks located on both sides of said signal to gather information on position and
direction of the trains on the tracks and said unit being interfaced with said color-light
signal to read, process and wirelessly transmit the gathered information and signals
generated by said color-light signal; and an electronic receiving unit placed in a
locomotive approaching, leaving or stationed at the color-light signal to wirelessly
receive, decode and display in audio-visual form the signals and information transmitted
by the electronic signaling unit; whereby the audio-visual display presents signal status
shown on the color-light and the position and direction of the trains on the tracks to a
locomotive driver.
According to another embodiment of the invention, a system independent radio
transceiver and electronic interface is placed inside the station and is interfaced to the
signaling system or with the data logger to monitor and obtain feedback on the aspects of
signals.
According to another embodiment of the invention, the unit has pre-fed GPS codes of the
physical position of the Railway color light signals that are placed in the station and yard
premises. It is able to wirelessly transmit status aspects along with the GPS coordinates to
enable the locomotive in that section to know its aspects.
According to another embodiment of the invention, the radar system comprises a set of
radar units focused on the tracks in an opposite direction such that individual radar faces
one side of the track along its length in a slanting manner.
According to another embodiment of the invention, the slant is about fifteen degrees.
According to another embodiment of the invention, the signaling unit comprises an
electrical interface unit configured to convert electrical signals generated by said colorlight
signal to electronic form; a first electronic unit configured to interpret and process
the converted signals and the information gathered by the radar system; and a first
electronics and radio transceiver unit to code and transmit the processed signals through a
radio frequency link using a first directional antenna.
According to another embodiment of the invention, receiving unit comprises a second
directional antenna to receive signals and information transmitted by the first radio
transceiver unit; a second electronics and radio transceiver unit to interpret signals and
information received by the second directional antenna and convert them to electronic
and digital form; a second electronic unit configured to interpret and process the
converted signals and information; and a display unit to decode and display the processed
signals and information in audio-visual form.
According to another embodiment of the invention, the signaling unit comprises a
computing unit to take decisions on braking of the locomotive and a wireless transmitter
to convey such decisions to the receiving unit.
According to another embodiment of the invention, the signaling unit is configured to
wirelessly transmit signals within a distance of four kilometers in a known direction.
According to another embodiment of the invention, when the locomotive conies within a
range of the signals transmitted by the signaling unit, the signal-receiving unit
communicates automatically with the signaling unit to present audio-visual display of
signal status to the locomotive driver.
According to another embodiment of the invention, the receiving unit is provided with an
audio-visual alarm to automatically activate and alert the driver in case of disobedience
of signal status presented by the display by the driver.
According to another embodiment of the invention, the receiving unit is configured to
monitor an onboard Doppler radar provided on the locomotive to convert speed and time
data into distance traveled to calculate accurate position of the locomotive.
According to another embodiment of the invention, the receiving unit is configured to
monitor a Global Positioning System (GPS) provided on the locomotive and activate the
audio-visual alarm in case of disobedience of GPS based data analysis.
According to another embodiment of the invention, the receiving unit is configured to
activate brake actuator unit in case of disobedience of signal status and information
presented by the display, excessive speeding or disobedience of Global Positioning
System (GPS) based data analysis by the driver and ensure emergency stopping of the
locomotive.
According to yet another embodiment of the invention, a method of monitoring railway
trackside color-light signals and position and direction of trains on tracks is provided,
which comprises providing an electronic signaling unit on and interfaced with said colorlight
signal and having a radar system mounted on said color-light signal to beam
microwaves across railway tracks located on both sides of said signal to gather
information on position and direction of the trains on the tracks; converting electrical
signals generated by said color-light signal and information gathered by said radar system
to electronic form; interpreting and processing the converted signals and information;
coding and transmitting the processed signals and information through a radio frequency
link using a first directional antenna; placing an electronic receiving unit in a locomotive
approaching, leaving or stationed at the color-light signal; receiving signals and
information transmitted by the first directional antenna by using a second directional
antenna; interpreting signals and information received by the second directional antenna
and converting them to electrical and digital form; and decoding and displaying the
signals and the information in audio-visual form; whereby the display in audio-visual
form presents signal status shown on the color-light and the information gathered by the
radar system to a locomotive driver.
Brief Description of the Drawings
Figure 1 shows a detailed view of various components of wireless device according to an
embodiment of the present invention.
Figure 2 shows the use of an embodiment of the present invention in existing Railway
infrastructure.
Figure 3 shows the use of an embodiment of the present invention in existing Railway
infrastructure.
Figure 4 shows the use of an embodiment of the present invention in existing Railway
infrastructure.
Figure 5 shows the use of an embodiment of the present invention in existing Railway
infrastructure
Figure 6 shows use of another embodiment of the present invention in existing Railway
infrastructure.
For a better understanding of the embodiments of the invention and to show how it may
be performed, it will now be described in more detail with reference to the accompanying
drawings.
Detailed Description of the Invention
As can be seen in Figure 1, the railway signal 14 (though home is most appropriate one
but any applicable signal can be used as well) has been interfaced with the signaling unit
12. This unit has an electrical interface 16, which connects to the signal lamps and
converts the status to readable form. It has an Electronics and radio transceiver 18, which
has a microcomputer onboard, and a radio antenna 56 is also provided. It senses the color
light signal lamp status and stores them for further processing. The signaling unit has two
on board radar units 20. These radars are focused on the tracks in opposite directions such
that individual radar faces to one side of the track along its length with approximately
fifteen degrees slant and other on the other side of the track in similar fashion. These
microwave radar unit beams are placed in such a manner that they intersect slantingly
both the adjacent up and down lines and also on the opposite direction. The signaling unit
also has an Electronic and Radio transceiver unit 18, which has a wireless transceiver
onboard and is used to convey the data to locomotive from the Railway Signal. In the
signaling scheme shown are two tracks, i.e. Up track 22 and the Down track 24. It is
necessary that as per railway rules, the trains follow independent tracks for Up and Down
directions in the normal operations unless the section has a single track or bidirectional
track. When the train leaves the station yard limit, it has to be on its properly allocated
track. In case it takes a wrong track meant for the other side of traffic, the head-on
collision may occur. The Radar units 20 mounted on the Railway signal 14 are
configured in such a manner that they check the Locomotive direction and its location on
the track simultaneously. The moment a train 26 approaches the radar footprint 28 from
the wrong direction as can be seen in Figure 2, the device immediately warns the driver
and if this warning is not acknowledged, the train control device shall cause emergency
brake application and also initiates a distress signal via Radio waves through receiving
unit 10 for warning the trains coming on that line for a distance range of approximately 4
Km.
As can be seen in figure 3, a train 30 approaching the signaling unit 12 from the correct
direction, this train has a receiving unit 10, which keeps searching the Signaling unit 12
for requisite data from a distance of few kilometers and the signaling unit 12 provides
signal status via radio frequency 32 to this seeking receiving unit. The locomotive 30 has
a receiving unit 10 as shown in detail in Figure 1, which has an audio-visual display and
control panel 52 to inform the driver about status of signal and action to be taken. In
addition, it has electronics and radio transceiver 34 to interpret, compute and fetch signal
from the signaling unit 12 through radio link 32 provided by radio antenna 54 and
information from radar system. This unit also has a GPS 36 for measuring signaling unit
placed coordinates, which are programmed onetime into the unit during its installation.
The receiving unit also has a Doppler radar odometer 38 onboard to measure exactly the
distance from the particular railway signal. If the railway signal status is green, it lets the
train pass. In case, the signal status is red, the receiving unit 10 brings in the information
from the GPS 36, and the Doppler radar odometer 38. This input works out the distance
of the train from the railway signal under interrogation. In this case as the system
requires the driver to stop on red, it warns the driver not to overshoot and stop at the
signal 14. The unit also activates its onboard radar units to see if the correct procedure
has been followed and train has not overshot the signal.
In regular working mode of the invention, when the train approaches the Rail signal
Home 14 from the block section side 40, the receiving unit 10 fetches Rail signal home
14 status from the signaling unit 12 from a few kilometers in advance. It keeps a watch
on the train movement and warns the driver or applies emergency brakes if appropriate
action is not taken. The receiving unit 10 has a Doppler odometer 38 and a GPS 36
onboard for coordinates estimation to check where the signal is placed exactly. The signal
has its own GPS data fed codes to identity its location. In the event of the train crossing a
yard in conditions of some malfunctioning and its jumping to non allocated track, the
Rail signal home 14 mounted signaling unit 12 interrogates its position on track and its
direction. The moment it identifies any mistake in track allocation it warns the driver and
applies brake to the train to avoid any head on collision from the other side. The
receiving unit also creates a radio frequency danger zone to warn traffic from the other
sides such that no collision takes place.
Figure 4 shows the operations of an embodiment of the invention in single line block
section that means a section in Railway where instead of two lines for traffic, only single
line is there and the bi-directional track 42 train movements are commuted. The rail
signal home 14 at both the block section 40 ends are equipped with the signaling unit,
which tags the direction of movement to the locomotive receiving unit 10 which enters
the section, through onboard radar units 20. The locomotive onboard receiving unit
checks the signal status and again checks its direction with respect to the Rail signal
Home 14. If it enters the section, it transmits the GPS data fed parameters that is the
signal identification number on the block section 40 in an area of 4 kilometers ahead to
caution its presence in that signal zone and its direction. In the event of another train on
the line heading from head on or rear, the radar would match the direction and the loco
drivers would be advised to take appropriate action through the on board unit. There is
another alternative available in the system wherein the signaling unit is able to log the
entry of the train in terms of date and time format and also would caution other entering
and exit locomotives from the signal radar units 20 in the same direction, unless these
parameters have not been neutralized by the appositively exiting train locomotive, thus
showing a line clear status on the signaling unit 12 if the desired scheme is one
locomotive to enter the section and leave turn by turn.
Even if the two trains enter in the block section they would come to know the direction
and presence of the other train in that block section. Figure 4 implementation also
protects any type of collision since the direction of trains are known in advance to the
receiving unit 10 through Radar units 20.
Figure 5 shows the station Yard implementation scheme another goal of the present
invention. In this scheme the station 44 has a signal known as Advance Starter or Starter
46, which is crossed by the train 26 when it leaves the station outer boundary and enters
the block section 40. This Advance starter signal 46 is interlocked through track circuit
wherein feedback from the tracks are analyzed by the cabin equipments changes the
Advance starter signal aspects are automatically put to red the moment train axle leaves
contact with the track section at the Station Track circuit End 48. The Advance starter 46
is a color light signal with two aspects Red and Green. With green aspect, the train is
allowed to proceed and the moment it crosses the Station Track circuit End 48, the Signal
status is automatically put to red. With the Signaling Unit 12 mounted on the advance
starter signal 46 and the locomotive 26 reaches this signal, this unit (12) transmits the
signal status and its onboard pre-programmed coordinates .The locomotive 26 matches
these coordinates against the true coordinates through the onboard GPS 36 to identify the
signal.
Once this is confirmed, it crosses the Advance starter 46 and keeps a track of xthe
parameters of signaling unit 12. The moment the train leaves the Station Track circuit
End point 48; its status is automatically changed to red as per standard signaling norms.
This status, now continuously transmitted, is received and analyzed by the unit on the
locomotive 26, to ensure that loco has proceeding on the correct line. In case the loco
happens to cross to the other line due to some unforeseen reasons in the double track
block section line, the advance starter aspects would never change to red as the train in
this case would not have been on the proper line from which through track circuit this
section is initiated. With locomotive 26 not receiving acknowledgement from the
Advance starter 46, the receiving unit 10 checks the distance of the locomotive 26 from
the advance starter 46 and warns the driver about his proceeding on wrong track. Once
this warning is available to the driver, he is expected to take appropriate actions and in
case of ignorance of this warning the device can cause automatic brake application to the
train. In another design scenario radar units 20 can also be used to confirm the
movement.
Figure 5 also shows a scheme with opposite lines Up track and Down track where color
light rail signal home 14 and Advance starter signals 46 are placed outside the station
yard for Railway traffic control. These signals (two opposite rail signal homes 14) are
further networked together through radio frequency. The advance starters 46, if required,
could also be networked in this scheme to further strengthen the process. In this scheme
when the Locomotive 26 enters the station yard from the block section 40, it exchanges
data with its side Rail signal home 14. The home signal aspects enable the locomotive
unit to take appropriate action as the aspect conveys to the driver whether he is required
to stop, or pass through this line or main line etc. The signaling unit 12 logs in these
status details along with the time day date stamp and direction of the train. The receiving
unit 10, on the other hand, logs the signal details allocated to this locomotive 26 and
saves these parameters. It is pointed out that when the train leaves the station, it crosses
the opposite line home signal 14 and its own Advance starter signal 46. As the Rail signal
home 14 under interrogation is networked to the other line's home and advance starter
signal 46 of the station, on its crossing the station, it also interrogates with the other line's
home 14 and/or the advance starter signal 46. While proceeding, train 26 relays its
parameters to the other tracks home signal 14, which were fed by the entry point home
signal 14 to the receiving unit 10. Since the two signals are already networked including
this parameter exchange, any wrong allocation in the yard causes the onboard receiving
unit 10 to check and analyze the track occupancy. Depending on the analysis the driver
can be informed well in advance regarding any possibility of rear collision.
If signal power fails or due to some problem and the color light signals do not work, the
Signaling unit has an onboard Capacitor bank, battery and Charger unit 50 that stores
electricity to power the wireless. The moment the signal power fails, it provides these
unsafe or signal failure parameters to the locomotive driver and the driver can take any
appropriate action to control the arising damage through this malfunction.
As can be seen in Figure 6, a station cell 59 has been provided for regular or optional use
for enhanced safety. This system is interfaced to the Station signaling system and is
known as signaling system data logger 58, or it may be interfaced individually to the
control outputs coming out of the relays before being distributed to the various signals
that comes under that particular railway station. It has an electrical interface unit 16 to
carry out this function. This unit converts the control signals in terms of electrical
machine-readable form. This data after suitable conversion is tagged with pre measured
GPS codes of the color light signals and is transmitted wirelessly at intervals with an
electronics and radio transceiver 18 and its antenna 56. This unit station cell 59 transmits
radio signals in a small local loop with controlled signal strength covering only one
railway station area communicating with its color light signal and few kilometers beyond
the signals to communicate with any approaching or retarding locomotive 26 in that area.
This provides wireless status from one single place with the use of pre-fed GPS codes. It
also diagnoses and monitors the signals placed in the field.

I Claim:
1. A wireless device for monitoring railway trackside color-light signals and position
and direction of trains and like transits, comprising:
an electronic signaling unit having a radar system to beam microwaves
across railway tracks located on both sides of said signal to gather information on
position and direction of the trains on the tracks and said unit being interfaced
with said color-light signal to read, process and wirelessly transmit the gathered
information and signals generated by said color-light signal; and
an electronic receiving unit placed in a locomotive approaching, leaving or
stationed at the color-light signal to wirelessly receive, decode and display in
audio-visual form the signals and information transmitted by the electronic
signaling unit;
whereby the audio-visual display presents signal status shown on the
color-light and the position and direction of the trains on the tracks to a
locomotive driver.
2. The device as claimed in claim 1, wherein said radar system comprises:
a set of radar units focused on the tracks in an opposite direction such that
each radar faces one side of the track along its length in a slanting manner.
3. The device as claimed in claim 2, wherein said slant is approximately fifteen
degrees.
4. The device as claimed in any one of the preceding claims, wherein said signaling
unit comprises:
an electrical interface unit configured to convert electrical signals
generated by said color-light signal to electronic form;
a first electronic unit configured to interpret and process the converted
signals and the information gathered by the radar system; and
a first electronics and radio transceiver unit to code and transmit the
processed signals through a radio frequency link using a first directional antenna.
5. The device as claimed in any of the preceding claims, wherein said receiving unit
comprises:
a second directional antenna to receive signals and information transmitted
by the first radio transceiver unit;
a second electronics and radio transceiver unit to interpret signals and
information received by the second directional antenna and convert them to
electronic and digital form;
a second electronic unit configured to interpret and process the converted
signals and information; and
a display unit to decode and display the processed signals and information
in audio-visual form.
6. The device as claimed in any of the preceding claims, wherein the signaling unit
comprises a computing unit to take decisions on braking of the locomotive and a
wireless transmitter to convey such decisions to the receiving unit.
7. The device as claimed in any of the preceding claims, wherein said signaling unit
is configured to wirelessly transmit signals within a distance of four kilometers in
a known direction.
8. The device as claimed in any of the preceding claims, wherein when the
locomotive comes within a range of the signals transmitted by the signaling unit,
the signal-receiving unit communicates automatically with the signaling unit to
present audio-visual display of signal status to the locomotive driver.
9. The device as claimed in any of the preceding claims, wherein the receiving unit
is provided with an audio-visual alarm to automatically activate and alert the
driver in case of non-observance of signal status presented by the display by the
driver.
10. The device as claimed in any of the preceding claims, wherein the receiving unit
is configured to monitor an onboard Doppler radar provided on the locomotive to
convert speed and time data into distance traveled to calculate accurate position of
the locomotive.
11. The device as claimed in any of the preceding claims, wherein the receiving unit
is configured to monitor a Global Positioning System (GPS) provided on the
locomotive and activate the audio-visual alarm in case of disobedience of GPS
based data analysis.
12. The device as claimed in any of the preceding claims, wherein the receiving unit
is configured to activate brake actuator unit in case of disobedience of signal
status and information presented by the display, excessive speeding or nonobservance
of Global Positioning System (GPS) based data analysis by the driver
and ensure emergency stopping of the locomotive.
13. The device as claimed in any of preceding claims, comprising a station cell unit
having a signaling system data logger to convert control signals into electronicmachine
readable form using an electrical interface unit, to tag the converted
signals with pre-measured GPS codes and to wirelessly transmit the tagged
signals using an electronics and radio transceiver and antenna.
14. A method of monitoring railway trackside color-light signals, position and
direction of trains and like transits, comprising:
providing an electronic signaling unit on and interfaced with said colorlight
signal and having a radar system mounted on said color-light signal to beam
microwaves across railway tracks located on both sides of said signal to gather
information on position and direction of the trains on the tracks;
converting electrical signals generated by said color-light signal and
information gathered by said radar system to electronic form;
interpreting and processing the converted signals and information;
coding and transmitting the processed signals and information through a
radio frequency link using a first directional antenna;
placing an electronic receiving unit in a locomotive approaching, leaving
or stationed at the color-light signal;
receiving signals and information transmitted by the first directional
antenna by using a second directional antenna;
interpreting signals and information received by the second directional
antenna and converting them to electrical and digital form; and
decoding and displaying the signals and the information in audio-visual
form;
whereby the display in audio-visual form presents signal status shown on
the color-light and the information gathered by the radar system to a locomotive
driver.