TECHNICAL FIELD
[0001] The present invention belongs to the technical field of traffic, and particularly
relates to a train group control method and system based on an ad-hoc network.
BACKGROUND ART
[0002] At present, trains usually operate in a marshalling mode, and a peer-to-peer communication
mode or a train-to-ground-to-train communication mode is usually used as a communication
mode.
[0003] The peer-to-peer communication mode is as follows:
a train A, after receiving a command from a ground control center, needs to perform
peer-to-peer communication with a train B, then the train A establishes communication
connection with the train B via a peer-to-peer communication, the train A provides
speed and position coordinates information to the train B, and the train B generates
a respective train control curve of the train B by combining the respective position
and speed information to control the train operation, based on the received information
of the train A. By analogy, each of the train C and the train D will generate a respective
train control curve to control the respective train operation.
[0004] Such method depends upon the ground center equipment, each train must receive a control
common for which train to communication with before establishing communication, and
cannot form a formation by itself. The train cannot directly obtain how many trains
are in the group and what train it is. Each train needs to calculate a respective
movement authority in real time.
[0005] The train-to-ground-to-train communication mode is as follows:
a train A and a train B are subjected to peer-to-peer communication by means of a
ground base station, the train A provides speed and position coordinates information
to the base station, the base station forwards such information to the train B, and
the train B generates a train control valve of the B train by combining the respective
position and speed information to control the train operation, based on the received
information of the train A. By analogy, each of the train C and the train D will generate
a respective train control curve to control the respective train operation.
[0006] In accordance with such method, each train must provide which train to communicate
with by means of ground center control equipment before establishing the communication
connection with the target train by means of the ground base station. Each train needs
to calculate a respective movement authority in real time. Wireless coverage is required
throughout the track. A central equipment needs to be provided to manage the position
and states of all trains.
[0007] No matter the peer-to-peer communication mode or the train-to-ground-to-train communication
mode is used, a train management center needs to be arranged on the ground, continuous
coverage of the ground wireless network is needed, and the requirement for network
indexes is high. Each train performs communication connection with a specified train
according to a command provided by the ground, and each train needs to calculate its
own movement authority in real time, but the functions of autonomous management and
autonomous networking of the train cannot be achieved. The ground train management
center cannot operate normally when having a failure, the construction cost is high,
the system is huge and miscellaneous, the reliability is low, and the maintenance
cost is high.
SUMMARY
[0008] For the problems above, the present invention provides a train group control method
based on an ad-hoc network. The method includes:
searching for, by ad-hoc network equipment on a train, communication equipment of
another train within a preset distance; determining whether the train is on the same
track as another train;
if determining that the train is on the same track as another train, determining whether
a networking condition is satisfied;
if the networking condition is satisfied, determining whether an ad-hoc network exists
or not;
if no ad-hoc network exists, establishing, by another train satisfying the networking
condition, an ad-hoc network with an original train;
if an ad-hoc network exists, adding another train satisfying the networking condition
to the ad-hoc network; and
controlling, by the train set in the ad-hoc network, the train operation in the ad-hoc
network by means of the ad-hoc network.
[0009] Further, the networking condition includes:
ad-hoc network equipment is provided in a target train;
the target train is allowed to establish or join the ad-hoc network; and
the target train is in stable communication with a local train.
[0010] Further, the control method further includes:
receiving, by the train, track condition information, wherein the track condition
information includes: route information, track information, temporary speed restriction
information, and movement authority.
[0011] Further, controlling, by a train set in the ad-hoc network, the train operation in
the ad-hoc network by means of the ad-hoc network includes:
a first train control and a following train control,
wherein the first train control is used in the ad-hoc network to enable the first
train to control the operation of another train in the ad-hoc network; and
the following train control is used in the ad-hoc network to enable a following train
to control itself to operate following a front train.
[0012] Further, the first train control includes:
each of the trains in the ad-hoc network determines a respective position in the ad-hoc
network,
if the train is the first train,
the first train receives train data information transmitted from the following train,
wherein the data information includes: a speed, a position, an acceleration, a braking
performance, and an operating condition;
the first train calculates a target speed of the following train in the ad-hoc network
according to the data information, the track information of a current position of
each train in the ad-hoc network and a position-speed relation between each train
and a front train in the group;
the first train notifies the corresponding train to monitor and operate according
to the target speed by means of ad-hoc network communication;
the first train periodically receives real-time train data information of another
train;
if the train is the following train,
the following train sends data information to the first train, the data information
including: a speed, a position, an acceleration, a braking performance and an operating
condition;
the following train receives the target speed transmitted from the first train by
means of the ad-hoc network, operates according to the target speed, and periodically
sends the real-time train data information of the current train to the first train.
[0013] Further, the first train control further includes:
the first train calculates a target distance between another train and the front train
in the ad-hoc network;
the first train calculates a distance-to-go curve of another train in the ad-hoc network;
the first train calculates a target stop point of another train in the ad-hoc network;
the first train sends the target distance, the distance-to-go curve and the target
stop point to the corresponding following train via the ad-hoc network communication;
and
the following train receives the target distance, the distance-to-go curve and the
target stop point.
[0014] Further, the following train control includes:
each of the trains in the ad-hoc network determines a respective position in the ad-hoc
network,
if the train is the first train,
the first train periodically transmits the respective train data information to a
rear train, wherein the data information includes: a speed, a position, an acceleration,
a braking performance and an operating condition;
if the train is the following train,
and is not the last train in the ad-hoc network,
the following train periodically receives the train data information transmitted from
the front train in the ad-hoc network, calculates a respective target speed, and operates
according to the target speed; and
the following train periodically transmits the respective train data information to
the rear train, the data information including: a speed, a position, an acceleration,
a braking performance and an operating condition;
if the train is the last train in the ad-hoc network,
the train periodically receives the train data information transmitted from the front
train in the ad-hoc network, calculates the respective target speed, and operates
according to the target speed.
[0015] Further, the following train control further includes:
the following train calculates a target distance between the respective position and
the front train in the ad-hoc network;
the following train calculates a respective distance-to-go curve in the ad-hoc network;
and
the following train calculates a respective target stop point in the ad-hoc network.
[0016] The present invention further provides a train group control system based on an ad-hoc
network. The system includes an ad-hoc equipment.
[0017] The ad-hoc network equipment is configured to:
search for, by ad-hoc network equipment on a train, communication equipment of another
train within a preset distance; determining whether a train is on the same track as
another train;
if determining that the train is on the same track as another train, determine whether
a networking condition is satisfied;
if the networking condition is satisfied, determine whether an ad-hoc network exists
or not;
if no ad-hoc network exists, establish, by another train satisfying the networking
condition, an ad-hoc network with an original train;
if an ad-hoc network exists, add another train satisfying the networking condition
to the ad-hoc network; and
controlling, by the train set in the ad-hoc network, the train operation in the ad-hoc
network by means of the ad-hoc network.
[0018] Further, the networking condition includes:
ad-hoc network equipment is provided in a target train;
the target train is allowed to establish or join the ad-hoc network; and
the target train is in stable communication with a local train.
[0019] Further, the system further includes:
on-board ATP equipment, a station data server, and a track circuit.
[0020] The on-board ATP equipment is configured to receive track condition information,
the track condition information includes: route information, track information, temporary
speed restriction information, and movement authority.
[0021] The station data server is configured to send the route information, the track information
and the temporary speed restriction information.
[0022] The track circuit sends the movement authority.
[0023] Further, controlling, by a train set in the ad-hoc network, the train operation in
the ad-hoc network by means of the ad-hoc network includes:
a first train control and a following train control,
wherein the first train control is used in the ad-hoc network to enable the first
train to control the operation of another train in the ad-hoc network; and
the following train control is used in the ad-hoc network to enable a following train
to control itself to operate following a front train.
[0024] Further, the first train control includes:
each of the trains in the ad-hoc network determines a respective position in the ad-hoc
network,
if the train is the first train,
the first train receives train data information transmitted from the following train,
wherein the data information includes: a speed, a position, an acceleration, a braking
performance, and an operating condition;
the first train calculates a target speed of the following train in the ad-hoc network
according to the data information, the track information of a current position of
each train in the ad-hoc network and a position-speed relation between each train
and a front train in the group;
the first train notifies the corresponding train to monitor and operate according
to the target speed by means of ad-hoc network communication;
the first train periodically receives real-time train data information of another
train;
if the train is the following train,
the following train sends data information to the first train, the data information
including: a speed, a position, an acceleration, a braking performance and an operating
condition;
the following train receives the target speed transmitted from the first train by
means of the ad-hoc network, operates according to the target speed, and periodically
sends the real-time train data information of the current train to the first train.
[0025] Further, the first train control further includes:
the first train calculates a target distance between another train and the front train
in the ad-hoc network;
the first train calculates a distance-to-go curve of another train in the ad-hoc network;
the first train calculates a target stop point of another train in the ad-hoc network;
the first train sends the target distance, the distance-to-go curve and the target
stop point to the corresponding following train via the ad-hoc network communication;
and
the following train receives the target distance, the distance-to-go curve and the
target stop point.
[0026] Further, the following train control includes:
each of the trains in the ad-hoc network determines a respective position in the ad-hoc
network,
if the train is the first train,
the first train periodically transmits the respective train data information to a
rear train, wherein the data information includes: a speed, a position, an acceleration,
a braking performance and an operating condition;
if the train is the following train,
and is not the last train in the ad-hoc network,
the following train periodically receives the train data information transmitted from
the front train in the ad-hoc network, calculates a respective target speed, and operates
according to the target speed; and
the following train periodically transmits the respective train data information to
the rear train, the data information includes: a speed, a position, an acceleration,
a braking performance, and an operating condition;
if the train is the last train in the ad-hoc network,
the train periodically receives the train data information transmitted from the front
train in the ad-hoc network, calculates the respective target speed, and operates
according to the target speed.
[0027] Further, the following train control further includes:
the following train further calculates a target distance between the respective position
and the front train in the ad-hoc network;
the following train further calculates a respective distance-to-go curve in the ad-hoc
network; and
the following train further calculates a respective target stop point in the ad-hoc
network.
[0028] The train group control method and system based on the ad-hoc network designed by
the present invention can achieve the train group control based on a train-to-train
communication technology of the ad-hoc network. Trains are automatically networked
when the conditions are satisfied, and inter-train data are transmitted between the
trains without relying on the ground base station. No central control equipment needs
to be arranged on the ground, and no wireless network coverage is needed in a ground
section. A train interval is dynamically adjusted according to track conditions, a
temporary speed restriction and the states of various trains in the group.
[0029] Additional features and advantages of the present invention will be set forth in
the description which follows, and in part will be apparent from the description,
or may be learned by practice of the present invention. The objectives and other advantages
of the present invention will be realized and attained by the structure particularly
pointed out in the specification, the claims as well as the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] To describe the technical solutions in the embodiments of the present invention or
in the prior art more clearly, the following briefly introduces the accompanying drawings
required for describing the embodiments. Apparently, the accompanying drawings in
the following description show merely some embodiments of the present invention, and
a person of ordinary skill in the art may still derive other drawings from these accompanying
drawings without creative efforts.
FIG. 1 illustrates a flow diagram of a train group control method based on an ad-hoc
network in accordance with embodiments of the present invention;
FIG. 2 illustrates a schematic diagram of a system of a train group system method
based on an ad-hoc network in accordance with embodiments of the present invention.
DETAILED DESCRIPTION
[0031] In order to make the objective, technical solutions and advantages of the embodiments
of the present invention more clearly, the following clearly and completely describes
the technical solutions in the embodiments of the present invention with reference
to the accompanying drawings in the embodiments of the present invention. Apparently,
the described embodiments are merely a part rather than all of the embodiments of
the present invention. All other embodiments obtained by a person of ordinary skill
in the art based on the embodiments of the present invention without creative efforts
shall fall within the protection scope of the present invention.
[0032] The embodiment of the present invention discloses a train group control method based
on an ad-hoc network. As shown in FIG. 1, the method includes: searching for, by ad-hoc
network equipment on a train, communication equipment of another train within a preset
distance; determining whether the train is on the same track as another train; if
the train is on the same track as another train, determining whether a networking
condition is satisfied; if the networking condition is satisfied, establishing an
ad-hoc network by the trains satisfying the networking condition; and controlling,
by the train set in the ad-hoc network, the train operation in the ad-hoc network
by means of the ad-hoc network. The networking condition includes: ad-hoc network
equipment is provided in a target train; the target train is allowed to establish
the ad-hoc network; and the target train is in stable communication with a local train.
The train receives track condition information, the track condition information includes:
route information, track information, temporary speed restriction information, and
movement authority.
[0033] The current train communication ways are train-to-ground communication and train-to-train
communication. The train-to-ground communication refers to that the train communicates
with ground equipment. The train-to-train communication is also divided into train-to-ground-to-train
communication and train-to-train communication. The train-to-ground-to-train communication
refers to that a plurality of trains perform communication by means of the ground
equipment, or perform communication by means of information of the ground equipment.
The train obtains the information of another train by means of the ground equipment,
such as a data interaction center, and then communicates with another train according
to the obtained information, which belongs to the train-to-ground-to-train communication.
The train-to-train communication refers to that the communication connection is established
between trains, and the communication and the disconnection of communication are completely
completed by train equipment without relying on the ground equipment. The communication
involved in the present invention is the train-to-train communication; the establishment
of the ad-hoc network, the use of the ad-hoc network communication and the disconnection
of communication are all completed by on-board equipment without relying on the ground
equipment. The present invention is mainly used in the field of heavy wagons, and
can also be used in the field of another train. All trains in the ad-hoc network are
controlled by the ad-hoc network, all trains in the ad-hoc network are called group
trains, and are also called a train set. The group trains refer to a train group consisting
of two or more real trains, the ground equipment controls control the train group
by one train, and various trains in the train group are subjected to coordinated control.
[0034] Specifically, the train receives the track condition information, the track condition
information includes: route information, track information, temporary speed restriction
information, and movement authority.
[0035] Illustratively, the train operation requires a series of authorities and relevant
data, and can be performed only after these authorities and data are obtained. Such
data include: the route information, the temporary speed restriction information,
and the track information. The authority includes the movement authority. These data
may be transmitted to the train using, but not limited to, the following ways: the
train receives the data by using on-board ATP (automatic train protection) equipment;
a station data server (SDS), which has the function of storing basic data of the station
and section track, may complete real-time framing and verification of a wireless message
according to the track information stored by itself and information provided by equipment
such as CBI (computer-based interlocking) and TSRS (temporary speed restriction server).
The station data server sends the information to all trains in the wireless coverage
area by means of train-to-ground communication, and may also send the information
to a specified train as required. The station data server receives interlocking route
information, temporary speed restriction information of the temporary speed restriction
server and the track information, generates messages such as the route information,
the track information and temporary speed restriction, and provides, within the scope
of the station, the in-station messages and section message to the on-board ATP. A
track circuit (TC) sends the movement authority information to the on-board ATP. The
train can receive the track condition information by means of such way.
[0036] Specifically, the ad-hoc network equipment on the train searches for communication
equipment of another train within a preset distance to determine whether the train
is on the same track as another train.
[0037] Illustratively, the ad-hoc network equipment on the train searches for communication
equipment of another train within the preset distance. When a front train and a rear
train operate according to normal tracking, the communication range of the ad-hoc
network equipment on the train is large enough, so that the front train and the rear
train can normally communicate with each other. The train-to-train communication of
the ad-hoc network equipment is performed by means of two radios that are both original
train equipment, without adding hardware equipment. One of the radios is configured
for long-distance communication, and the other of the radios is configured for short
and medium-distance communication. The switching of the two radio stations is completed
by the ad-hoc network equipment. After communication is established between two or
more ad-hoc network equipment and the networking condition is satisfied, a local wireless
broadband communication private network may be established within a short time in
an ad-hoc manner. All ad-hoc network equipment in the wireless broadband communication
private network communicates with one another by using the wireless broadband communication
private network. After the wireless broadband communication private network has been
established, new ad-hoc network equipment is communicatively connected to any ad-hoc
network equipment in the wireless broadband communication private network, and when
networking condition is satisfied, the new ad-hoc network equipment will automatically
join the wireless broadband communication private network to form a new wireless broadband
communication private network. The communication between the new ad-hoc network and
all ad-hoc network equipment under the jurisdiction of the original wireless broadband
communication private network is achieved by means of the new wireless broadband communication
private network. The ad-hoc network equipment on the train searches for communication
equipment of another train within the preset distance, the preset distance, such as
the shortest distance between a front train and a rear train in normal tracking operation,
the longest distance of long-distance communication of the radio station, may be appointed
in advance.
[0038] The ad-hoc network equipment is arranged at a head of the train. When ad-hoc network
equipment on the train sends a wireless signal to the periphery, and communication
equipment of end of train (EOT) of this train, communication equipment of head of
train (HOT) of another train within the preset distance, communication equipment of
EOT of another train and the ad-hoc network equipment of another train can all receive
the signal. The ad-hoc network equipment has a function of identifying communication
equipment of HOT and communication equipment of EOT of a neighboring-line train, thereby
preventing the head of the train or the end of the train of neighboring line train
from being included in the wireless communication network. The identification may
be performed using, but not limited to, the following ways: the ad-hoc network equipment
sends networking request information to the periphery and informs the track where
it is located; the train on the same track, after receiving the networking request
information, replies its corresponding information, and the train on different track
does not reply or replies information including the respective track information.
The ad-hoc network equipment may determine which trains are on the same track as itself
according to the received information.
[0039] Specifically, whether the networking condition is satisfied is determined, if the
networking condition is satisfied, the trains satisfying the networking condition
establish the ad-hoc network, and the train set in the ad-hoc network controls the
train operation in the ad-hoc network by means of the ad-hoc network. The networking
condition includes: ad-hoc network equipment is provided in a target train; the target
train is allowed to establish the ad-hoc network; and the target train is in stable
communication with a local train.
[0040] Illustratively, the establishment of the ad-hoc network between the trains needs
to satisfy the networking condition, the networking condition includes: ad-hoc network
equipment is provided in the target train, the target train is allowed to establish
the ad-hoc network; and the target train is in stable communication with a local train.
The train can join the ad-hoc network only when being provided with the ad-hoc network
equipment. Any train provided with the ad-hoc network equipment has a function of
permitting or prohibiting the itself to establish or join the ad-hoc network. When
a certain train is set to permit itself to establish or join the ad-hoc network by
itself, after another train sends an ad-hoc network establishing request or an ad-hoc
network joining request to this train, this train establishes an ad-hoc network or
joins the ad-hoc network when all networking conditions are satisfied. The train establishing
the ad-hoc network needs to maintain stable communication. The communication equipment
of EOT of the train plays a communication relay role. When the train is in a tunnel
or a cave, the head of the train may communicate with another train via the communication
equipment of EOT, and another train may communicate with the head of the train via
the communication equipment of EOT of this train. During the establishment of the
ad-hoc network, two sets of ad-hoc network equipment may communicate with each other
via the communication equipment of EOT, and the stable communication is also considered
to be stable communication between the target train and the local train. During the
establishment of the ad-hoc network, there may be a plurality of trains in the ad-hoc
network, and the ad-hoc network equipment also plays a role of communication relay.
When any train in the ad-hoc network communicates with the target train, regardless
of direct communication or communication by means of the relay of other one or a plurality
of trains in the ad-hoc network, the communication between the target train and the
current train is considered to be stable as long as the communication is stable.
[0041] When the networking condition is satisfied, the ad-hoc network equipment on the train
determines whether there is an ad-hoc network at present. If no ad-hoc network exists,
all trains satisfying the networking condition are configured to establish the ad-hoc
network with the original train. If the ad-hoc network already exists, all the trains
satisfying the networking conditions join the original ad-hoc network to form a new
ad-hoc network.
[0042] After the ad-hoc network is established, the train sets in the ad-hoc network control
the train operation in the ad-hoc network by means of the ad-hoc network.
[0043] Specifically, controlling, by a train set in the ad-hoc network, the train operation
in the ad-hoc network by means of the ad-hoc network includes: a first train control
and a following train control. The first train control is used in the ad-hoc network
to enable the first train to control the operation of another train in the ad-hoc
network; the following train control is used in the ad-hoc network to enable the following
train to control itself to operate following a front train.
[0044] Illustratively, the train set in the ad-hoc network controls the operation of trains
in the ad-hoc network by means of the ad-hoc network in two ways: one is the first
train control, that is, in the ad-hoc network, the first train controls the operation
of another train in the ad-hoc network; one is the following train control, that is,
in the ad-hoc network, the following train controls itself to operate following the
front train. An operator may select the specific control way according to actual situations.
[0045] Specifically, the first train control includes: each of the trains in the ad-hoc
network determines a respective position in the ad-hoc network, If the train is the
first train, the first train receives train data information transmitted from the
following train, wherein the data information includes: a speed, a position, an acceleration,
a braking performance, and an operating condition; the first train calculates a target
speed of the following train in the ad-hoc network according to the data information,
the track information of a current position of each train in the ad-hoc network and
a position-speed relation between each train and the front train in the group; the
first train notifies the corresponding train to monitor and operate according to the
target speed by means of ad-hoc network communication; and then the first train periodically
receives real-time train data information of another train; If the train is the following
train, the following train sends data information to the first train, wherein the
data information includes: a speed, a position, an acceleration, a braking performance
and an operating condition; the following train receives the target speed transmitted
from the first train by means of the ad-hoc network, operates according to the target
speed, and periodically sends the real-time train data information of the current
train to the first train. The first train further calculates a target distance between
another train in the ad-hoc network and the preceding train; the first train further
calculates a distance-to-go curve of another train in the ad-hoc network; the first
train further calculates a target stop point of another train in the ad-hoc network;
the first train sends the target distance, the distance-to-go curve and the target
stop point to the corresponding following train via the ad-hoc network communication;
and the following train receives the target distance, the distance-to-go curve and
the target stop point.
[0046] Illustratively, all trains in the ad-hoc network are all on the same track, according
to operation directions of the trains, the headmost train in the ad-hoc network is
the first train of the group and is also called as the first train, and the trains
except the first train are the following trains of the group. Each of the trains in
the ad-hoc network may determine the respective position in the ad-hoc network using,
but not limited to the following ways: each of the trains in the ad-hoc network sends
the respective position information to another train, and may obtain the respective
position in the ad-hoc network by combining the position information of all the trains
with traveling direction information and track information of the current train. The
train may obtain the following information by determining the respective position
in the ad-hoc network: whether it is the first train or the following train, and if
it is the following train, what position it is in. If there are four in the ad-hoc
network, the train behind the first train is the second position (the second train),
and the last train is the fourth (the fourth train).
[0047] The first train in the ad-hoc network receives train data information transmitted
from another train, the data information include: a speed, a position, an acceleration,
a braking performance, and an operating condition.
[0048] The first train calculates a target speed of the following train in the ad-hoc network
according to the data information, the track information of a current position of
each train in the ad-hoc network and a position-speed relation between each train
and the front train in the group.
[0049] The operating condition refers to different states of the train in operation, the
train under locomotive traction includes five types: traction inertia, air braking,
electric braking and air-electricity blended braking. The different operating conditions
of the train affect a value of a train braking model parameter, and thus affect the
determination of the target speed.
[0050] The target speed refers to the highest speed allowed before reaching the target point.
The first train notifies notify the corresponding train to operate according to the
target speed via the ad-hoc network communication. The first train operates under
the control of the ground equipment. In this way, the trains in the ad-hoc network
may operate at the maximum speed. During operation, the following train in the ad-hoc
network periodically sends the respective real-time train data information to the
first train, wherein the data information includes a speed, a position, an acceleration,
a braking performance, and an operating condition; the period is calculated according
to the target speed of the train, the position of the preceding train, the braking
performance, the track condition and the like, and is less than safety braking time.
The safety braking time is the maximum time of one-off braking for ensuring that the
current train can operate safely after operating according to the target speed.
[0051] The following train receives the target speed transmitted from the first train by
means of the ad-hoc network, operates according to the target speed. The first train
periodically receives receive the real-time train data information of the following
train. The first train recalculates a new target speed according to the real-time
train data information and sends the new target speed to the corresponding train,
and the thus following train operates according to the new target speed. The first
train monitors the actual speed and the target speed of the following train in real
time, and controls the traction and braking of the following train by combining a
train traction model and a braking model. Finally, the closed-loop supervision of
the first train on another train is completed.
[0052] The first train may calculate the target speed using , but is not limited to, the
following ways: during operation, a rear train needs to maintain a safety spacing
S from the front train to ensure the safety of operation. The first train determines
the distance L between itself and the rear train according to the position sent by
the rear train (the second train) via the ad-hoc network communication, and obtains
a least-favorable braking distance D (including safety protection distance) under
the response time according to the information such as the respective speed, acceleration
and breaking performance. The safety spacing S of the rear train is equal to the sum
of the L and D; the first train calculates the target speed of the rear train according
to the safety spacing S data and a safety braking model of the rear train. In a similar
way, the first train may calculate a target speed of each of the third train, the
fourth train and the like.
[0053] The first train further calculates a target distance between another train in the
ad-hoc network and the front train, the target distance refers to the distance between
the front end of the train and the target point. The target distance refers to the
safety spacing S, namely, L+D, and a calculation way of the safety spacing S has appeared
in how to calculate the target speed. The first train further calculates a distance-to-go
curve of another train in the ad-hoc network.
[0054] The distance-to-go curve is a one-off braking control curve generated on the basis
of the target speed, the target distance, the track condition, and the train characteristics
to ensure the safe train operation. The distance-to-go curve may be calculated using,
but not limited to, the following ways: the first train acquires relevant parameters
of the trains in the set, and the first train calculates the most restrictive speed
profile (MRSP) according to the track information of the train in the set, fixed speed
restriction, track temporary speed restriction, train construction speed restriction,
mode speed restriction and the like. The track information, the fixed speed restriction,
the track temporary speed restriction, the train construction speed restriction and
the mode speed restriction are provided by the ground equipment. When components of
the MRSP change, the first train recalculates the MRSP. The safety braking model takes
influences of factors such as a position uncertainty of a train, an initial speed
of the train, an initial acceleration of the train, a speed measurement error, a track
gradient, a braking delay and an action delay of the train into consideration.
[0055] The initial speed of the train is obtained by a speed sensor. The initial acceleration
of the train is obtained by calculating a traction force and the mass according to
the
Regulations on Railway Train Traction Calculation. The track gradient is provided by the ground equipment; errors of the position uncertainty
of the train, the braking delay, the speed measurement error and the action delay
of the train are stipulated by a system. The first train monitors a difference between
a current speed and a current speed restriction of the train in a monitoring set,
and according to the current positioning information, a distance-to-go curve of this
train is calculated by combining the train safety braking model. The first train further
calculates a target stop point of another train in the ad-hoc network. The calculation
may be performed using, but not limited to the following ways: the first train calculates
the position range of the tail of the train when it stops, based on its own relevant
parameter; the closest distance between the tail part of the first train after stopping
and the rear train is used as a target stop point of the rear train; and then a braking
measure grade, opportunity and the like which should be taken by the rear train are
calculated according to the relevant parameters of the rear train, thereby guaranteeing
that the rear train does not cross the target stop point of the rear train after stopping.
Similarly, the first train may calculate target distances, distance-to-go curves,
and target stop points of all trains in the ad-hoc network, and then send such information
to the corresponding trains. The following train receives the target distance, the
distance-to-go curve and the target stop point. When an emergency occurs, such as
inability to communicate, the following train may safely stop or operate according
to the information.
[0056] Specifically, the following train control includes: each of the trains in the ad-hoc
network determines a respective position in the ad-hoc network; if the train is the
first train, the first train periodically transmits respective train data information
to a rear train, wherein the data information includes: a speed, a position, an acceleration,
a braking performance and an operating condition. If the train is the following train,
and is not the last train in the ad-hoc network, the following train periodically
receives the train data information transmitted from the front train in the ad-hoc
network, calculates a respective target speed, and operates according to the target
speed, and then the following train periodically transmits the respective train data
information to the rear train, wherein the data information includes: a speed, a position,
an acceleration, a braking performance and an operating condition. IF the train is
the last train in the ad-hoc network, the train periodically receives the train data
information transmitted from the front train in the ad-hoc network, calculates the
respective target speed, and operates according to the target speed. The following
train control further includes: the following train calculates a target distance between
the respective position and the front train in the ad-hoc network; the following train
further calculates a respective distance-to-go curve in the ad-hoc network; and then
the following train further calculates a respective target stop point in the ad-hoc
network.
[0057] Illustratively, the use of the following train control also requires each train in
the ad-hoc network to determine the respective position in the ad-hoc network, and
the used way is the same as that of the first train control.
[0058] Except for the last train in the ad-hoc network, each train periodically transmits
respective train data information to the rear train, wherein the data information
includes: a speed, a position, an acceleration, a braking performance and an operating
condition. Except for the first train, each train receives train data information
transmitted from the front train, calculates respective target speed, and operates
according to the target speed. The first train operates under the control of the ground
equipment. The rear train periodically receives the train data information of the
front train and recalculates a new target speed, and then operates according to the
new target speed. The following train monitors its actual speed and the target speed
in real time, and controls the train traction and braking by combining a train traction
model and a braking model.
[0059] The following train may calculate the respective target speed using, but is not limited
to, the following ways: during operation, the rear train needs to maintain a safety
spacing S from the front train to ensure the safety of operation. The following train
determines a distance L between itself and the rear train according to the position
sent by the front train via the ad-hoc network communication, and obtains the least-favorable
braking distance (including safety protection distance) under the response time according
to the information such as the speed, the acceleration and the breaking performance
of the front train. The safety spacing S of the local train is equal to the sum of
the L and D; the local train calculates a respective target speed according to the
safety spacing S and a respective safety braking model.
[0060] The following train further calculates a target distance between itself and the front
train in the ad-hoc network, namely, L+D; the following train further calculates a
respective distance-to-go curve in the ad-hoc network; and the following train further
calculates a respective target stop point in the ad-hoc network. The distance-to-go
curve may be calculated using, but not limited to, the following ways: the following
train calculates the respective most restrictive speed profile (MRSP) according to
respective relevant parameters by combining train track information, a fixed speed
restriction, a track temporary speed restriction, a train construction speed restriction,
a mode speed restriction and the like. When the components of the MRSP change, the
following train recalculates the MRSP. The safety braking model takes influences of
factors such as a position uncertainty of a train, an initial speed of the train,
an initial acceleration of the train, a speed measurement error, a track gradient,
a braking delay and an action delay of the train into consideration. The following
train monitors a difference between its own actual speed and the current limit restriction
in real time, and calculates the respective distance-to-go curve according to the
current positioning information by combining a train safety braking model. The following
train further calculates a respective target stop point. The calculation may be carried
out using, but not limited to, the following ways: the rear train calculates the position
range of a tail of the train when the front train stops, based on the relevant parameters
of the front train; the closest distance between the tail part of the front train
after stopping and the rear train is used as a target stop point of the rear train,
and then the rear train calculates a braking measure grade, opportunity and the like
which should be taken according to the respective relevant parameters, thereby guaranteeing
that the rear train does not cross the respective target stop point after stopping.
Each of the following trains calculates a respective target distance, a respective
distance-to-go curve, and a respective target stop point. When an emergency occurs,
such as inability to communicate, the following train may safely stop or operate according
to the information.
[0061] The embodiment of the present invention further discloses a train group control system
based on an ad-hoc network. As shown in FIG. 2, the system includes ad-hoc network
equipment, on-board ATP equipment, a station data server, and a track circuit.
[0062] The ad-hoc network equipment is configured to: search for, by ad-hoc network equipment
on a train, communication equipment of another train within a preset distance; determine
whether the train is on the same track as another train; if the train is in the same
track of another train, determine whether a networking condition is satisfied; if
the networking condition is satisfied, determine whether an ad-hoc network exists
or not; if no ad-hoc network exists, establish, by another train satisfying the networking
condition, an ad-hoc network with an original train; if an ad-hoc network exists,
add another train satisfying the networking condition to the ad-hoc network; and control,
by the train set in the ad-hoc network, the train operation in the ad-hoc network
by means of the ad-hoc network. The networking condition includes: the ad-hoc network
equipment is provided in a target train; the target train is allowed to establish
or join the ad-hoc network, and the target train is in stable communication with a
train.
[0063] The on-board ATP equipment is configured to receive track condition information,
wherein the track condition information include: route information, track information,
temporary speed restriction information, and a movement authority.
[0064] The station data server is configured to send the route information, the track information
and the temporary speed restriction information. The station data server has the function
of storing basic data of the station and section track, and may complete real-time
framing and verification of a wireless message according to track information stored
by itself and information provided by equipment such as CBI and TSRS. The station
data server sends the information to all the trains in the wireless coverage area
by means of train-to-ground communication, and may also send the information to a
specified train as required. The station data server receives interlocking route information,
temporary speed restriction information of the temporary speed restriction server
and the track information, generates messages such as the route information, the track
information and temporary speed restriction, and provides, within the scope of the
station, the in-station messages and section message to the on-board ATP.
[0065] The track circuit sends the movement authority.
[0066] The controlling, by a train set in the ad-hoc network, the train operation in the
ad-hoc network by means of the ad-hoc network includes: a first train control and
a following train control. The first train control is used in the ad-hoc network to
enable the first train to control the operation of another train in the ad-hoc network;
and the following train control is used in the ad-hoc network to enable a following
train to control itself to operate following a front train.
[0067] The first train control includes: each of the trains in the ad-hoc network determines
a respective position in the ad-hoc network. If the train is the first train, the
first train receives train data information transmitted from the following train,
wherein the data information includes: a speed, a position, an acceleration, a braking
performance and an operating condition; the first train calculates a target speed
of the following train in the ad-hoc network according to the data information, the
track information of a current position of each train in the ad-hoc network and a
position-speed relation between each train and the front train in the group; the first
train notifies the corresponding train to monitor and operate according to the target
speed by means of ad-hoc network communication; and the first train periodically receives
real-time train data information of another train. If the train is the following train,
the following train sends data information to the first train, wherein the data information
includes: a speed, a position, an acceleration, a braking performance and an operating
condition; the following train receives the target speed transmitted from the first
train by means of the ad-hoc network, operates according to the target speed, and
periodically sends the real-time train data information of the current train to the
first train.
[0068] The first train control further includes: the first train further calculates a target
distance between another train and the front train in the ad-hoc network; the first
train further calculates a distance-to-go curve of another train in the ad-hoc network;
and the first train further calculates a target stop point of another train in the
ad-hoc network. The first train sends the target distance, the distance-to-go curve
and the target stop point to the corresponding following train via the ad-hoc network
communication. The following train receives the target distance, the distance-to-go
curve and the target stop point.
[0069] The following train control includes: each of the trains in the ad-hoc network determines
a respective position in the ad-hoc network. If the train is the first train, the
first train periodically transmits the respective train data information to a rear
train, wherein the data information includes: a speed, a position, an acceleration,
a braking performance and an operating condition. If the train is the following train,
and is not the last train in the ad-hoc network, the following train periodically
receives the train data information transmitted from the front train in the ad-hoc
network, calculates a respective target speed, and operates according to the target
speed, and then the following train periodically transmits the respective train data
information to the rear train, wherein the data information includes: a speed, a position,
an acceleration, a braking performance and an operating condition. If the train is
the last train in the ad-hoc network, the train periodically receives the train data
information transmitted from the front train in the ad-hoc network, calculates the
respective target speed, and operates according to the target speed.
[0070] The following train control further includes: the following train further calculates
a target distance between the respective position and the front train in the ad-hoc
network; the following train calculates the respective distance-to-go curve in the
ad-hoc network; and the following train calculates the respective target stop point
in the ad-hoc network.
[0071] The train group control method and system based on the ad-hoc network designed by
the present invention can achieve the train group control based on a train-to-train
communication technology of the ad-hoc network. Trains are automatically networked
when the conditions are satisfied, and inter-train data are transmitted between the
trains without relying on the ground base station. No central control equipment needs
to be arranged on the ground, and no wireless network coverage is needed in a ground
section. A train interval is dynamically adjusted according to track conditions, a
temporary speed restriction and the states of various trains in the group.
[0072] Although the utility model has been described in detail with respect to the previously
described embodiments, it should be appreciated by one skilled in art, the technical
solutions recorded in the embodiments may be still modified, or part of its technical
features may be replaced with equivalents; and such modifications or substitutions
do not deviate the nature of the technical solutions from the spirit and scope of
the technical solutions of the various embodiments in the utility model.
1. A train group control method based on an ad-hoc network, characterized in that, the method comprises: searching for, by ad-hoc network equipment on a train, communication
equipment of another train within a preset distance; determining whether the train
is on the same track as another train; if determining that the train is on the same
track as another train, determining whether a networking condition is satisfied; if
the networking condition is satisfied, determining whether an ad-hoc network exists
or not; if no ad-hoc network exists, establishing, by another train satisfying the
networking condition, an ad-hoc network with an original train; if an ad-hoc network
exists, adding another train satisfying the networking condition to the ad-hoc network;
and controlling, by the train set in the ad-hoc network, the train operation in the
ad-hoc network by means of the ad-hoc network.
2. The control method according to claim 1, characterized in that, the networking condition comprises: ad-hoc network equipment is provided in a target
train; the target train is allowed to establish or join the ad-hoc network, and the
target train is in stable communication with a local train.
3. The control method according to claim 1, characterized in that, the control method further comprises: receiving, by the train, track condition information,
the track condition information comprising: route information, track information,
temporary speed restriction information, and a movement authority.
4. The control method according to claim 1, characterized in that, the controlling, by a train set in the ad-hoc network, the train operation in the
ad-hoc network by means of the ad-hoc network comprises: a first train control and
a following train control, wherein the first train control is used in the ad-hoc network
to enable the first train to control the operation of another train in the ad-hoc
network; and the following train control is used in the ad-hoc network to enable a
following train to control itself to operate following a front train.
5. The control method according to claim 4, characterized in that, the first train control comprises: each of the trains in the ad-hoc network determines
a respective position in the ad-hoc network, if the train is the first train, the
first train receives train data information transmitted from the following train,
the data information comprising: a speed, a position, an acceleration, a braking performance,
and an operating condition; and wherein the first train calculates a target speed
of the following train in the ad-hoc network according to the data information, the
track information of a current position of each train in the ad-hoc network and a
position-speed relation between each train and the front train in the group; the first
train notifies the corresponding train to monitor and operate according to the target
speed by means of ad-hoc network communication; and the first train periodically receives
real-time train data information of another train; if the train is the following train,
the following train sends data information to the first train, the data information
comprising: a speed, a position, an acceleration, a braking performance and an operating
condition; the following train receives the target speed transmitted from the first
train by means of the ad-hoc network, operates according to the target speed, and
periodically sends the real-time train data information of the current train to the
first train.
6. The control method according to claim 5, characterized in that, the first train control further comprises: the first train calculates a target distance
between another train and the front train in the ad-hoc network ; the first train
calculates a distance-to-go curve of another train in the ad-hoc network; the first
train calculates a target stop point of another train in the ad-hoc network; the first
train sends the target distance, the distance-to-go curve and the target stop point
to the corresponding following train via the ad-hoc network communication; and the
following train receives the target distance, the distance-to-go curve and the target
stop point.
7. The control method according to claim 4, characterized in that, the following train control comprises: each of the trains in the ad-hoc network
determines a respective position in the ad-hoc network; if the train is the first
train, the first train periodically transmits respective train data information to
a rear train, the data information comprising: a speed, a position, an acceleration,
a braking performance and an operating condition; if the train is the following train,
and is not the last train in the ad-hoc network, the following train periodically
receives the train data information transmitted from the front train in the ad-hoc
network, calculates a respective target speed, and operates according to the target
speed, and then the following train periodically transmits the respective train data
information to the rear train, the data information comprising: a speed, a position,
an acceleration, a braking performance and an operating condition; if the train is
the last train in the ad-hoc network, the train periodically receives the train data
information transmitted from the front train in the ad-hoc network, calculates the
respective target speed, and operates according to the target speed.
8. The control method according to claim 7, characterized in that, the following train control further comprises: the following train calculates a
target distance between the respective position and the front train in the ad-hoc
network; the following train calculates the respective distance-to-go curve in the
ad-hoc network; and the following train calculates the respective target stop point
in the ad-hoc network.
9. A train group control system based on an ad-hoc network, characterized in that, the system comprises ad-hoc network equipment, wherein the ad-hoc network equipment
is configured to: search for, by ad-hoc network equipment on a train, communication
equipment of another train within a preset distance; determine whether the train is
on the same track as another train; if the train is in the same track of another train,
determine whether a networking condition is satisfied; if the networking condition
is satisfied, determine whether an ad-hoc network exists or not; if no ad-hoc network
exists, establish, by another train satisfying the networking condition, an ad-hoc
network with an original train; if an ad-hoc network exists, add another train satisfying
the networking condition to the ad-hoc network; and control, by the train set in the
ad-hoc network, the train operation in the ad-hoc network by means of the ad-hoc network.
10. The control system according to claim 9, characterized in that, the networking condition comprises: ad-hoc network equipment is provided in a target
train; the target train is allowed to establish or join the ad-hoc network, and the
target train is in stable communication with a local train.
11. The control system according to claim 9, characterized in that, the system further comprises: on-board ATP equipment, a station data server, and
a track circuit, wherein the on-board ATP equipment is configured to receive track
condition information, the track condition information comprising: route information,
track information, temporary speed restriction information, and movement authority;
the station data server is configured to send the route information, the track information
and the temporary speed restriction information; and the track circuit sends the movement
authority.
12. The control system according to claim 9, characterized in that, the controlling, by a train set in the ad-hoc network, the train operation in the
ad-hoc network by means of the ad-hoc network comprises: a first train control and
a following train control, wherein the first train control is used in the ad-hoc network
to enable the first train to control the operation of another train in the ad-hoc
network; and the following train control is used in the ad-hoc network to enable a
following train to control itself to operate following a front train.
13. The control system according to claim 12, characterized in that, the first train control comprises: each of the trains in the ad-hoc network determines
a respective position in the ad-hoc network, if the train is the first train, the
first train receives train data information transmitted from the following train,
the data information comprising: a speed, a position, an acceleration, a braking performance
and an operating condition; the first train calculates a target speed of the following
train in the ad-hoc network according to the data information, the track information
of the current position of each train in the ad-hoc network and a position-speed relation
between each train and the front train in the group; the first train notifies the
corresponding train to monitor and operate according to the target speed by means
of ad-hoc network communication; the first train periodically receives real-time train
data information of another train; if the train is the following train, the following
train sends data information to the first train, the data information comprising:
a speed, a position, an acceleration, a braking performance and an operating condition;
the following train receives the target speed transmitted from the first train by
means of the ad-hoc network, operates according to the target speed, and periodically
sends the real-time train data information of the current train to the first train.
14. The control system according to claim 13, characterized in that, the first train control further comprises: the first train calculates a target distance
between another train and the front train in the ad-hoc network ; the first train
calculates a distance-to-go curve of another train in the ad-hoc network; the first
train calculates a target stop point of another train in the ad-hoc network; the first
train sends the target distance, the distance-to-go curve and the target stop point
to the corresponding following train via the ad-hoc network communication; and the
following train receives the target distance, the distance-to-go curve and the target
stop point.
15. The control system according to claim 12, characterized in that, the following train control comprises: each of the trains in the ad-hoc network
determines a respective position in the ad-hoc network; if the train is the first
train, the first train periodically transmits respective train data information to
a rear train, the data information comprising: a speed, a position, an acceleration,
a braking performance and an operating condition; if the train is the following train,
and is not the last train in the ad-hoc network, the following train periodically
receives the train data information transmitted from the front train in the ad-hoc
network, calculates a respective target speed, and operates according to the target
speed, and then the following train periodically transmits the respective train data
information to the rear train, the data information comprising: a speed, a position,
an acceleration, a braking performance and an operating condition; and if the train
is the last train in the ad-hoc network, the train periodically receives the train
data information transmitted from the front train in the ad-hoc network, calculates
the respective target speed, and operates according to the target speed.
16. The control system according to claim 12, characterized in that, the following train control further comprises: the following train calculates a
target distance between the respective position and the front train in the ad-hoc
network; the following train calculates the respective distance-to-go curve in the
ad-hoc network; and the following train calculates the respective target stop point
in the ad-hoc network.