MESSAGE CONTROLLING AND TRANSMISSION DEVICE
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a message
controlling and transmission device that transmits a
message including various information data.
Description of the Related Art
An example of a device that transmits a message with
various information data includes a message controlling
and transmission device in the field of railway, wherein
the device transmits information data to a railway
vehicle, a railway signal, a railway track monitoring
device, and the like, or the railway vehicle and the
railway track monitoring device transmit various
information data to a ground controlling device. These
data transmission devices are configured to be fail-safe,
in order to prevent transmission of wrong message data
from the transmission side to the reception side.
More specifically, when there is a failure or an
abnormality in the message transmission device, a wrong
message is transmitted, which is inconvenient. Therefore,
configurations disclosed in Japanese Patent Laid-Open
Publication No. 9-288630 (Patent Document 1) and Japanese
Patent Laid-Open Publication No. 2011-146965 (Patent
Document 2) are proposed.
In Japanese Patent Laid-Open Publication No. 9-
288630 (Patent Document 1), dual bus lines are provided,
and CPUs send out the same data to data buses of the dual
bus lines. Both data are compared, and if inconsistency
of both data is detected, the transmission of the data to
the outside is disabled.
In Japanese Patent Laid-Open Publication No. 2011-
146965 (Patent Document 2), the message transmission
device generates a transmission message and a validation
message at the same time. A modulator modulates the
transmission message and the validation message to
generate a combined carrier signal of the transmission
message and the validation message. Only frequency band
components of the transmission message are extracted and
transmitted to a rail. Meanwhile, a demodulator
demodulates the combined carrier signal to be output, and
the transmission message and the validation message are
taken out. A collation process of the validation message
and the transmission message is executed, and if the
collation result is incompatible, the transmission of the
transmission message is terminated.
In Japanese Patent Laid-Open Publication No. 9-
288630 (Patent Document 1) and Japanese Patent Laid-Open
Publication No. 2011-146965 (Patent Document 2), an
output message and a transmission channel that is a
carrier frequency band are multiplexed, and the collation
process is applied to the output message. In this way,
fail-safe of the device output is realized.
Japanese Patent Laid-Open Publication No. 9-288630
(Patent Document 1) describes a mechanism for realizing
the fail-safe of the output of the data transmission
device by multiplexing the output data and the
transmission channel and applying the collation process
to the output data. Japanese Patent Laid-Open
Publication No. 2011-146965 (Patent Document 2) describes
a mechanism for realizing the fail-safe of the output of
the data transmission device by multiplexing the output
message and the transmission channel that is a carrier
frequency band and applying the collation process to the
output message.
However, the output information and the transmission
channel are multiplexed in the transmission devices of
Japanese Patent Laid-Open Publication No. 9-288630
(Patent Document 1) and Japanese Patent Laid-Open
Publication No. 2011-146965 (Patent Document 2). As a
result, there are problems that the device configuration
is complicated, the device reliability is reduced with an
increase in the device failure rate due to the
complication, and the cost of the device is increased.
Therefore, an object of the present invention is to
provide a message controlling and transmission device
that improves the reliability of the device by realizing
the fail-safe without complicating the configuration of
the transmission device and that suppresses an increase
in the cost of the device.
SUMMARY OF THE INVENTION
The present invention can be figured out from a
plurality of aspects to solve the problems, and an
invention from a first aspect is as follows.
The present invention provides a message controlling
and transmission device including:
a controller unit that creates or prepares an output
message including control information to be transmitted
to an external device based on input information, selects
an output message from a plurality of messages including
the control information to be transmitted to the external
device, and transmits the output message to a message
switching information generation unit;
the message switching information generation unit
that creates message switching information which changes
every message output cycle, adds the created message
switching information to the output message transmitted
from the controller unit, and transmits the output
message added with the message switching information to
an output unit and a consistency checking module;
the consistency checking module that checks
consistency of an output message based on the output
message transmitted from the message switching
information generation unit and that transmits a checking
result to the output unit; and
the output unit that outputs the output message to
the outside of the device according to the checking
result of the consistency checking module, wherein
the output unit transmits the output message added
with the message switching information received from the
message switching information generation unit to the
consistency checking module as a read-back message,
the consistency checking module checks consistency
of the read-back message based on the output message
received from the message switching information
generation unit and transmits a checking result to the
output unit if the read-back message is consistent, and
the output unit outputs the output message to the outside
of the device.
The present invention can be figured out from a
plurality of aspects to solve the problems as described
above, and inventions from other aspects will be
described in the following detailed description of the
preferred embodiments and the like.
According to the configuration of the present
invention, fail-safe message data output can be realized
in the message controlling and transmission device
through a single transmission channel, without
multiplexing of the transmission data and the
transmission system.
Other problems, configurations, and advantageous
effects will become apparent from the following
description of embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a data transmission
system in a field of railway signal safety, for
describing an application according to the present
invention;
FIG. 2 is a schematic block diagram for describing a
configuration of a first embodiment of the present
invention;
FIG. 3 is a flow chart for describing a process of
the first embodiment of the present invention;
FIG. 4 is a schematic block diagram for describing a
configuration of a second embodiment of the present
invention;
FIG. 5 is a schematic block diagram for describing a
configuration of a third embodiment of the present
invention;
- 6 -
FIG. 6 is a schematic block diagram for describing a
configuration of a fourth embodiment of the present
invention;
FIG. 7 is a flow chart for describing a process of
the fourth embodiment of the present invention; and
FIG. 8 is a schematic block diagram for describing
another configuration of the fourth embodiment of the
present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiments of the present invention will now be
described with reference to the drawings and the like.
The following embodiments illustrate specific examples of
the content of the present invention, and the present
invention is not limited to the embodiments. Those
skilled in the art can make various changes and
modifications within the technical scope disclosed in the
present specification. The same reference numerals are
provided to the parts with the same functions throughout
the drawings for describing the embodiments, and the
description may not be repeated.
[First Embodiment]
A first embodiment is an example of applying a
message controlling and transmission device of the
present invention to a field of railway safety.
As shown in FIG. 1, in the field of railway signal
safety, a message is transmitted to a running train (1)
through a ground beacon (2) installed along a railroad.
The present invention can be applied to a ground beacon
controller (4) that is connected to the ground beacon (2)
to control the ground beacon (2). The ground beacon
controller (4) includes a message controlling and
transmission device that creates or selects an
appropriate message based on external input information
from a signal (3) or from transmission means (5), such as
a transmission network and a centralized train command
device, and that transmits the message to the running
train (1) through the ground beacon (2).
FIG. 2 is a system schematic block diagram of the
first embodiment.
In FIG. 2, the message controlling and transmission
device of the first embodiment includes a controller unit
(6), a message switching information generation unit (7),
an output unit (8), and a consistency checking module (9).
The controller unit (6), the message switching
information generation unit (7), and the consistency
checking module (9) are mounted on a fail-safe control
board (15), such as a fail-safe control board (15)
including a dual circuit system in which CPU and other
parts are duplicated. On the other hand, the output unit
(8) may be mounted on an output board (16) that is not
fail-safe.
The controller unit (6) has a function of creating
an output message including control information used by
an external device, such as control information of
termination and deceleration of a running train, and
including redundant code information for protecting a
message bit string from environment noise. The
controller unit (6) also has a function of selecting an
output message from a plurality of prepared messages.
Transmission information used for transmission control,
including an address and the like of an on-board device
of the running train, may be further added to the output
message.
The message switching information generation unit 7
has a function of creasing message switching information
or message alternation information (collectively called
"message switching information") that changes and
alternates every message output cycle (for example, every
200 msec). The message switching information (or the
message alternation information) can be information
indicating the creation and presentation of a new message
or can be alternation information attached to the message
every message output cycle (for example, consecutive
numbers or consecutive codes such as 1, 2, 3 ... and A, B,
C ...) .
The output unit (8) has a function of sending out an
output message (21) to the outside of the device and has
a function of fixing the output for the outside of the
device to a safe side based on a signal (20) received
from the consistency checking module (9), such as a
function of suspending the transmission of the message by
terminating the output and a function of limiting the
output to a voltage value in a range that does not cause
the ground beacon to receive the message. The
consistency checking module (9) has a function of
checking the consistency of a read-back message read back
from the output unit (8) and a function of transmitting a
consistency checking result (20) related to the read-back
message to the output unit (8).
FIG. 3 shows a flow chart of operation of the
message controlling and transmission device of the first
embodiment.
In FIG. 3, the controller unit (6) acquires external
input information (17) from the outside of the device,
such as from a transmission network, a centralized train
command device, and a signal (step 31), and creates or
selects an output message based on the information (step
32). The created or selected message is transmitted to
the message switching information generation unit (7),
and the message switching information generation unit (7)
creates message switching information (alternation
- 10 -
information), adds the created message switching
information to the output message, and transmits a
transmission message (18) added with the message
switching information to the output unit (8) and the
consistency checking module (9) (step 33).
The output unit (8) transmits an output message (19)
added with the received message switch information to the
consistency checking module (9) as a read-back message
(step 34). The consistency checking module (9) uses the
output message (18) directly received from the message
switching information generation unit (7) to check the
consistency of the read-back message (19) and transmits
the checking result (20) of the consistency of the readback
message to the output unit (step 35). The output
unit (8) sends out the output message (21) to the outside
of the device if the consistency can be detected based on
the checking result (20) received from the consistency
checking module (9) (step 36). On the other hand, if
inconsistency is detected, a process of fixing the output
message for the outside of the device to the safe side is
executed (step 37), such as a process of suspending the
transmission of the message by terminating the output and
a process of limiting the output to a voltage value in a
range that does not cause the ground beacon to receive
the message. Various means can be implemented to
transmit the message to the external device, such as
- 11 -
wireless transmission using a wireless transmission
device and transmission through a track circuit (rail) if
a block section is arranged.
As described, the consistency of the read-back
message (19) read back from the output unit (8) is
checked to realize the fail-safe of the device output in
the first embodiment.
The output unit (8) needs countermeasures for a
stale failure caused by a fault in software or hardware,
in which an output message already output in a previous
cycle is erroneously transmitted as a read-back message
to the consistency checking module (9), and a wrong
output message is erroneously output to the outside of
the device. More specifically, the output unit (8)
includes a buffer of output message and outputs an output
message to the outside of the device after temporarily
storing the output message in the buffer. Due to a
failure, a new message is not output after the creation
of the new message, and an old message stored in the
buffer is continuously output. Countermeasures for such
a fault are necessary. For this stale failure of the
output unit, the message switching information
(alternation information) that changes every message
output cycle is added to the output message in the
message controlling and transmission device of the
present invention as described in the first embodiment.
- 12 -
Therefore, a message of a previous cycle is not output to
the outside of the device, and a stale failure in the
message controlling and transmission device can be
detected by checking the message switching information
(alternation information).
The output unit (8) sends out the output message
(21) to the outside of the device if the consistency can
be detected based on the checking result (20) received by
the consistency checking module (9) (step 36). The
output message may be an output message added with the
message switching information or may be an output message
without the message switching information. When the
output message added with the message switching
information is output, the output message can also be
used as message switching information in the external
device that receives the output message, and this can
contribute to the fail-safe.
[Second Embodiment]
FIG. 4 shows a schematic block diagram of a second
embodiment of the message controlling and transmission
device of the present invention.
The second embodiment is established based on the
first embodiment, and the difference between the second
embodiment and the first embodiment is that a data
compression unit 1 (10) that compresses data of the readback
message and a data decompression unit (14) that
- 13 -
decompresses the compressed read-back message transmitted
to the consistency checking module are arranged.
The data compression unit 1 (10) based on CRC or the
like and the data decompression unit (14) corresponding
to the data compression unit 1 are additionally mounted
on the message controlling and transmission device of the
second embodiment in order to reduce the transmission
load of the transmission path for transmitting the readback
message from the output unit (8) to the consistency
checking module (9).
The read-back message compressed by the data
compression unit 1 (10) is decompressed by the data
decompression unit (14) and transmitted to the
consistency checking module 9 to check the consistency.
The other operation is the same as the message
controlling and transmission device of the first
embodiment, and the description will not be repeated.
[Third Embodiment]
FIG. 5 shows a schematic block diagram of a third
embodiment of the message controlling and transmission
device of the present invention.
The message controlling and transmission device of
the third embodiment is established based on the first
embodiment, and the difference between the third
embodiment and the first embodiment is that the data
compression unit 1 (10) that compresses data of the read-
- 14 -
back message and a data compression unit 2 (11) that
compresses data of the transmission message 18 are
arranged.
The data compression unit 1 (10) based on CRC or the
like is also added to the message controlling and
transmission device of the third embodiment in order to
reduce the transmission load of the transmission path for
transmitting the read-back message from the output unit
(8) to the consistency checking module (9). The data
compression unit 2 (11) based on CRC or the like is
further added in order to reduce the transmission load of
the transmission path for transmitting the transmission
message from the message switching information generation
unit 7 to the consistency checking module.
The transmission message and the read-back message
compressed by the data compression unit 1 (10) and the
data compression unit 2 (11) are transmitted as
compressed data to the consistency checking module (9),
and the consistency of CRC output value is checked, for
example. The other operation is the same as the message
controlling and transmission device of the first
embodiment, and the description will not be repeated.
[Fourth Embodiment]
FIG. 6 shows a block diagram of a fourth embodiment
of the message controlling and transmission device of the
present invention.
- 15 -
The message controlling and transmission device of
the fourth embodiment is established based on the third
embodiment, and the difference between the fourth
embodiment and the third embodiment is that a storage A
(12) and a storage B (13) that store a plurality of
prepared messages and message indexes corresponding to
the prepared messages are additionally mounted on the
control board (15) and the output board (16),
respectively.
In the message controlling and transmission device
of the fourth embodiment, storages that store a plurality
of prepared messages prepared in advance and message
indexes corresponding to the prepared messages, i.e. the
storage A (12) and the storage B (13), are additionally
mounted on the control board and the output board,
respectively, to allow selecting a predetermined prepared
message. In the message controlling and transmission
device of the fourth embodiment, the controller unit (6)
transmits the message index corresponding to the created
or selected output message to the storage A (12) and the
storage B (13). The storage A (12) transmits the
prepared message corresponding to the received message
index to the message switching information generation
unit (7) as an output message, and the storage B (13)
transmits the prepared message corresponding to the
- 16 -
received message index to the output unit (8) as an
output message.
FIG. 7 shows a flow chart of operation when a
plurality of prepared messages are used in the message
controlling and transmission device of the fourth
embodiment.
In FIG. 7, the controller unit (6) acquires the
external input information (17) from the outside of the
device, such as from a transmission network, a
centralized train command device, and a signal (step 71),
and transmits the message index of the output message to
the storage A (12) and the storage B (13) based on the
information (step 72). The storage A (12) transmits the
prepared message corresponding to the selected message
index to the message switching information generation
unit (7) (step 73). The message switching information
generation unit (7) creates message switching information
(alternation information), outputs the created message
switching information and the output message body,
transmits the message switching information to the output
unit (8), transmits the message switching information and
the transmission message (18) to the data compression
unit 2 (11), and compresses and transmits the message
with the message switching information to the consistency
checking module (9) (step 74) . In this way, the
transmission load can be reduced by eliminating the
- 17 -
transmission and reception of the output message bodybetween
the control board and the output board.
The storage B (13) transmits the prepared message
corresponding to the selected message index to the output
unit (8) (step 75). The output unit (8) transmits the
output message added with the message switching
information received from the message switching
information generation unit (7) to the consistency
checking module (9) as a read-back message (19) through
the data compression unit 1 (10) (step 76). The
consistency checking module (9) uses compressed data (for
example, CRC) of the transmission message (18) received
from the data compression unit 2 (11) to check the
consistency of the compressed data of the read-back
message (19) and transmits the checking result (20) of
the consistency of the read-back message to the output
unit (step 77). Based on the checking result 20 received
from the consistency checking module (9), the output unit
(8) executes a process of sending out the output message
21 to the outside of the device if the consistency can be
detected (step 78) or a process of fixing the output
message for the outside of the device to the safe side if
inconsistency is detected or if a checking result of
consistency is not transmitted (step 79), such as a
process of suspending the transmission of the message by
terminating the output and a process of limiting the
- 18 -
output to a voltage value in a range that does not cause
the ground beacon to receive the message.
A configuration described in FIG. 8 is also possible.
In FIG. 6, the message index is transmitted to the
storage B, and the message switching information is
directly transmitted to the output unit. In the
configuration of FIG. 8, the control board is provided
with a message switching information combining unit that
combines the message index and the message switching
information. The message index with the message
switching information is transmitted to the storage B,
and the storage B transmits the message corresponding to
the message index received from the controller unit and
the message switching information to the output unit.
According to the configuration, the message index is
transmitted to the storage B through the message
switching information combining unit. Therefore, the
information for the message index does not have to match
in the storage A and the storage B.
As described, the fourth embodiment includes the
storages that store the plurality of prepared messages
prepared in advance and the message indexes corresponding
to the prepared messages, i.e. the storage A (12) and the
storage B (13), and the consistency is checked for the
read-back message (19) read back from the output unit (8)
based on consistency check of CRC output value, for
- 19 -
example. In this way, the fail-safe of the device output
is realized.
- 20

What is claimed is:
1. A message controlling and transmission device
comprising:
a controller unit comprising at least one of a
message creating unit that creates an output message
including control information used by an external device
and including redundant code information for protecting a
message bit string from environmental noise and a message
selecting unit that selects an output message from a
plurality of prepared messages;
a message switching information generation unit that
creates message switching information which changes every
message output cycle and that adds the created message
switching information to a message;
a consistency checking module that checks
consistency of an output message and that transmits a
checking result to an output unit if the output message
is not consistent; and
at least one of a message output unit that outputs
an output message to outside of the device and a fixation
message output unit that fixes output for the outside of
the device to a safe side, wherein
the controller unit creates or selects the output
message based on external input information acquired from
the outside of the device to transmit the output message
to the message switching information generation unit,
- 21 -
the message switching information generation unit
creates message switching information, adds the created
message switching information to a transmission message,
and transmits the transmission message added with the
message switching information to the output unit and the
consistency checking module,
the output unit transmits the output message added
with the message switching information received from the
message switching information generation unit to the
consistency checking module as a read-back message,
the consistency checking module uses the output
message directly received from the message switching
information generation unit to check consistency of the
read-back message and transmits a checking result to the
output unit if the read-back message is not consistent,
and the output unit fixes the output for the outside of
the device to the safe side.
2. The message controlling and transmission device
according to claim 1, wherein
the output unit transmits the read-back message to
the consistency checking module through a first data
compression unit, and
the consistency checking module uses the output
message received from the message switching information
- 22 -
generation unit to check the consistency of the read-back
message compressed by the first data compression unit.
3. The message controlling and transmission device
according to claim 2, wherein
the message switching information generation unit
transmits the output message to the consistency checking
module through a second data compression unit, and
the consistency checking module acquires the output
message compressed by the second data compression unit
and uses the acquired output message to check the
consistency of the read-back message compressed by the
first data compression unit.
4. The message controlling and transmission device
according to claim 3, further comprising
a storage A and a storage B that store a plurality
of prepared messages corresponding to message indexes,
wherein the controller unit selects the message index and
transmits the selected message index to the storage A and
the storage B, the storage A transmits a message
corresponding to the received message index to the
message switching information generation unit, and the
storage B transmits a message corresponding to the
message index received from the controller unit to the
output unit.
- 23 -
5. A message controlling and transmission device
comprising:
a controller unit that creates or prepares an output
message including control information to be transmitted
to an external device based on input information, selects
an output message from a plurality of messages including
the control information to be transmitted to the external
device, vand transmits the output message to a message
switching information generation unit;
the message switching information generation unit
that creates message switching information which changes
every message output cycle, adds the created message
switching information to the output message transmitted
from the controller unit, and transmits the output
message added with the message switching information to
an output unit and a consistency checking module;
the consistency checking module that checks
consistency of an output message based on the output
message transmitted from the message switching
information generation unit and that transmits a checking
result to the output unit; and
the output unit that outputs the output message to
the outside of the device according to the checking
result of the consistency checking module, wherein
- 24 -
the output unit transmits the output message added
with the message switching information received from the
message switching information generation unit to the
consistency checking module as a read-back message,
the consistency checking module checks consistency
of the read-back message based on the output message
received from the message switching information
generation unit and transmits a checking result to the
output unit if the read-back message is consistent, and
the output unit outputs the output message to the outside
of the device.
6. The message controlling and transmission device
according to claim 5, wherein
the output unit transmits the read-back message to
the consistency checking module through a first data
compression unit, and
the consistency checking module uses the output
message received from the message switching information
generation unit to check the consistency of the read-back
message compressed by the first data compression unit.
7. The message controlling and transmission device
according to claim 6, wherein
- 25 -
the message switching information generation unit
transmits the output message to the consistency checking
module through a second data compression unit, and
the consistency checking module acquires the output
message compressed by the second data compression unit
and uses the acquired output message to check the
consistency of the read-back message compressed by the
first data compression unit.
8. The message controlling and transmission device
according to claim 7, further comprising
a storage A and a storage B that store a plurality
of prepared messages corresponding to message indexes,
wherein the controller unit selects the message index and
transmits the selected message index to the storage A and
the storage B, the storage A transmits a message
corresponding to the received message index to the
message switching information generation unit, and the
storage B transmits a message corresponding to the
message index received from the controller unit to the
output unit.
9. The message controlling and transmission device
according to claim 7, further comprising
a storage A that stores a plurality of prepared
messages corresponding to message indexes, wherein the
- 26 -
controller unit selects the message index and transmits
the selected message index to the storage A, and
the storage A transmits a message corresponding to
the received message index to the message switching
information generation unit,
the message controlling and transmission device
further comprising a message switching information
combining unit that combines the message switching
information and the message index output from the message
switching information generation unit and that transmits
the message switching information and the message index
to a storage B that stores a plurality of prepared
messages corresponding to message indexes, wherein
the storage B transmits a message corresponding to
the message index received from the controller unit and
the message switching information to the output unit.
10. The message controlling and transmission device
according to any of claims 5, 6, 7, 8, and 9, wherein
the consistency checking module uses the output
message received from the message switching information
generation unit to check the consistency of the read-back
message, and if a checking result indicating that the
read-back message is inconsistent is transmitted or if a
checking result is not transmitted, the output unit fixes
the output for the outside of the device to the safe side.
- 27 -
11. The message controlling and transmission device
according to claim 10, wherein
if the checking result indicating that the read-back
message is inconsistent is transmitted or if the checking
result is not transmitted, the output unit does not
output the output message to the outside of the device.
12. The message controlling and transmission device
according to claim 10, wherein
if the checking result indicating that the read-back
message is inconsistent is transmitted or if the checking
result is not transmitted, the output unit outputs an
output message to the external device to instruct the
external device to terminate or limit operation.
13. The message controlling and transmission device
according to claim 10, wherein
the external device is an on-board device of a train
vehicle, and the output message is information data
transmitted from a ground beacon along a railroad to the
on-board vehicle of the train vehicle.
14. A message controlling and transmission device,
substantially as herein described with reference to
accompanying drawings and examples.