CN111082886B

CN111082886B - Networked train broadcasting system and implementation method

Info

Publication number: CN111082886B
Application number: CN201911138500.0A
Authority: CN
Inventors: 刘伟
Original assignee: Beijing Waycom Century Technology Co ltd
Current assignee: Beijing Waycom Century Technology Co ltd
Priority date: 2019-11-20
Filing date: 2019-11-20
Publication date: 2024-05-03
Anticipated expiration: 2039-11-20
Also published as: CN111082886A

Abstract

A networked train broadcasting system and an implementation method belong to the technical field of urban rail transit vehicles and motor train units. Adopting an all-Ethernet topology and matching with a digital multimedia terminal; the low-power-consumption terminal equipment adopts a POE power supply IEEE 802.3 af/at technology; the exchanger adopts dynamic host setting protocol DHCP to automatically distribute the IP address of the terminal equipment; a VoIP technology is adopted to realize visual digital intercom; based on gigabit Ethernet communication technology, with embedded processor as core, the system adopts full Ethernet topology, digital multimedia terminal, integrated control host, integrates three subsystems and Ethernet, and terminal equipment uses POE power supply and DHCP technology.

Description

Networked train broadcasting system and implementation method

Technical Field

The invention belongs to the technical field of urban rail transit vehicles and motor train units, and relates to a networked train broadcasting system and an implementation method.

Background

At present, a bus type control technology and an analog audio transmission technology are generally adopted in a vehicle-mounted broadcasting system of a subway light rail or a motor train unit; in the carriage transmission process, control signals and analog audio/video signals among carriage hosts are extremely easy to be interfered by environment and other system signals; the transmission mode of network topology is needed in the system.

The broadcast failure rate of the prior art is high:

In a semi-automatic station reporting mode in the prior art, a broadcasting system carries out station reporting logic operation through level signal changes of a gate, five kilometers and thirty kilometers, the failure rate of broadcasting station reporting is high, and the method is mainly characterized by station reporting errors, station failure, station jumping and the like, and specifically causes are as follows:

Software problem: the broadcasting station logic has BUG (vulnerability); MP3 playboard problem: poor contact of CF card and incapability of playing voice file; abnormal input of level signals of gates, five kilometers and thirty kilometers;

system errors caused by abnormal power failure in the prior art:

The system error caused by abnormal power failure mainly comprises the following aspects:

Program or script start failure; file system corruption; system log or monitor video loss, etc.

Main and standby redundancy functions in the prior art are imperfect:

The head-to-tail redundancy mechanism adopted at present has the following defects:

the host machine failure in single driver driving can not use the redundancy function of the tail car; the network is interrupted to easily cause double master control faults; the operation information of the host and the standby machine cannot be completely synchronized; redundant function switching is actually too slow and not as efficient as "restarting the host" in emergency situations.

Disclosure of Invention

The invention solves the technical problems existing in the prior art, thereby providing a networked train broadcasting system and an implementation method.

The prior art problem is solved by the following technical scheme:

A realization method of networked train broadcasting comprises the following steps;

An OCC (operation control center) manual broadcasting step: the control center OCC can be used for carrying out manual broadcasting on passengers in the operation process by wirelessly accessing a PIS (passenger information) system through a train-ground;

Manual broadcasting: the driver directly triggers the 'manual broadcasting' function through the PTT (push-to-talk) key of the handheld microphone of the console or the side walls at the two sides;

An OCC emergency broadcasting step: in a full-automatic driving mode, when a train encounters an emergency, and a fire disaster and serious faults occur, the control center OCC can be wirelessly connected to the PIS system through the train ground in the operation process to carry out emergency broadcasting on passengers;

an emergency broadcasting step: when a train encounters an emergency, and a fire disaster and serious faults occur, a driver operates PISM (a passenger information system display), and the emergency broadcasting operation broadcasts a voice file which is recorded in advance by a main control end PISC (a passenger information system controller) and contains contents such as command and dredging or sorry and pacifying to passengers;

full-automatic station reporting step: in a full-automatic stop reporting mode, PISC in a main control state receives an ATO (automatic train operation) stop reporting control instruction forwarded by a TCMS (train control and management system), and performs stop reporting on passengers according to preset stop reporting logic, wherein the stop reporting content is a digital voice file which is recorded in advance and stored in PISC;

and (3) standby broadcasting: by arranging an independent analog audio bus, an analog handheld microphone and a loudspeaker, a whole set of standby broadcasting scheme is formed, and when the digital broadcasting function cannot work normally, a driver cab shoutes the voice to the passenger room through the standby microphone, so that the manual broadcasting function is completed;

the driver presses a PTT side key of an MIC (microphone), key signals are collected by an analog power amplifier, each analog power amplifier device is controlled by a vehicle audio bus, and an audio processing channel is opened; each passenger room analog power amplifier is used for connecting audio to a passenger room loudspeaker line at ordinary times, and a driver speaks into the passenger room through a microphone to complete a manual broadcasting function; after the PTT side key of the MIC is released, the audio channel is disconnected;

Semi-automatic station reporting step: in a semi-automatic stop reporting mode, the main control state PISC carries out a stop reporting or a stop arrival reporting on passengers by collecting signals provided by trains, and the stop reporting content is a digital voice file which is recorded in advance and stored in PISC;

OCC manual station reporting step: in an unmanned full-automatic driving operation mode, the OCC manually designates the stop reporting content, and the PISC in the main control state starts or stops the stop reporting according to the stop reporting code provided by the OCC, wherein the stop reporting content is a digital voice file which is pre-recorded and stored in PISC;

Manual station reporting step: the driver designates the stop report content through PISM interface, and PISC starts or stops stop report according to the stop report code provided by PISM in the main control state, wherein the stop report content is a digital voice file which is pre-recorded and stored in PISC.

A networked vehicle-mounted broadcasting system adopts an all-Ethernet topology and is matched with a digital multimedia terminal; the low-power consumption terminal equipment adopts POE power supply IEEE 802.3af/at technology; the exchanger adopts dynamic host configuration protocol DHCP (dynamic host configuration protocol) to automatically allocate the IP address of the terminal equipment; a VoIP (Voice over Internet protocol) technology is adopted to realize visual digital intercom; based on gigabit Ethernet communication technology, with embedded processor as core, the system adopts full Ethernet topology, digital multimedia terminal, integrated control host, integrates three subsystems and Ethernet, and terminal equipment uses POE power supply and DHCP technology.

Based on the Ethernet construction, the terminal equipment is all digitized and is accessed into the Ethernet; the system host PISC should adopt a three-layer switch, the CCU (car controller) adopts a two-layer switch, and the terminal equipment is all digitized and connected into the ethernet; the train-level Ethernet adopts gigabit network to support two networking modes of link aggregation or ring topology; in the digital PIS, all terminals adopt Ethernet communication, and considering the wiring and debugging of the system, all terminals preferably adopt DHCP to set IP and the power supply adopts network cable to supply power; the guest room LCD display and the guide display (TGS) are distributed on two sides of the carriage, and are cascaded in a hand-in-hand mode, and a single terminal device is required to be provided with two Ethernet interfaces, and the two interfaces have Bypass functions.

The invention has the advantages that the system architecture is simpler by adopting the full Ethernet topology and matching with the digital multimedia terminal, and the state of each device can be monitored on line in real time; the low-power-consumption terminal equipment adopts POE power supply (IEEE 802.3 af/at) technology, so that wiring is simplified, and cost is saved; the exchanger adopts Dynamic Host Configuration Protocol (DHCP), automatically distributes the IP address of the terminal equipment, and simplifies the debugging and maintenance difficulty.

The invention aims at the defects of the prior art to upgrade:

1. reducing failure rate of broadcast station reporting errors

1) Planning and designing a stop reporting logic from the top layer, and combining the stop reporting logic of the existing stable operation project;

2) The embedded processor with high performance is adopted, the audio playing chip is integrated on the board card, the communication between boards is omitted, the on-board storage is supported, and the plugging of the card seat is avoided;

3) The method of using the gate signal and the speed signal is considered, the driving distance is calculated through the speed signal, the driving distance is not easy to be influenced by signal jitter, the gate signal is still needed to switch states, and the phenomenon of early station reporting or station non-reporting still exists when the speed signal is abnormal in acquisition or communication.

2. Perfecting master-slave redundancy function

The digital PIS adopts a scheme of a two-stage redundancy mechanism:

Primary redundancy: the system PISC host sets a main CPU module and a standby CPU module to realize the redundancy of the local end;

the system PISC host is provided with a main CPU module and a standby CPU module, so that the redundancy of the local end is realized, when the main CPU board card fails, the system is automatically switched to a second CPU board card to work, and after the switching, the manual work, the broadcasting report station and the intercom function at the head and the tail ends can be normally used. Under normal conditions, the main board card and the standby board card have a real-time data synchronization function.

Secondary redundancy: master-slave manual switching of the two-end PISC hosts of the system can realize tail redundancy:

When the redundant CPU is in primary redundancy, the redundant CPU has a problem, or PISM cannot detect the state of the host computer at the activation end PISC, PISM sends a prompt to a driver, the driver can manually switch the currently activated host computer PISC through PISM, and a real-time data synchronization function is provided between the host computers at the master and slave stations PISC. When the active-end PISC host fails (a block CPU failure or a network failure), the system prompts the driver to switch to the tail car PISC for operation. After the secondary redundancy is switched, the functions of manual broadcasting and broadcasting station reporting can still be realized at the fault end, but the monitoring function cannot be realized.

3. Reducing video loss caused by power failure or system error

Video storage is divided into two storage modes, namely centralized storage and distributed storage. Aiming at the centralized storage mode, the local video storage of the camera is added, so that when the hard disk mounting fails or the program is wrong, the camera can realize the local storage function; for the distributed storage mode, each passenger room storage module can store the monitoring video of the passenger room and the adjacent passenger rooms, and when the passenger room video storage module cannot work normally, the video storage module of the adjacent passenger rooms can continuously store the video of the camera, and the two video storage modules are not mutually influenced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art; as shown in the figure, wherein:

FIG. 1 is a schematic diagram of the structure of the present invention;

The invention will be further described with reference to the drawings and examples.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the invention; all other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

Example 1: as shown in fig. 1, a networked vehicle-mounted broadcasting system is provided, wherein a train broadcasting and passenger information processing module is respectively connected with an exchanger expansion module, an MVB (multifunctional vehicle bus) communication module, a level signal acquisition processing module, a marshalling network exchanger module, a digital audio forwarding, storing and multicasting module, a video storage module and an audio processing module, and a power module is respectively connected with the above modules.

The ground PIS module and the OCC module are respectively connected with the exchanger expansion module through a hundred megaEthernet, the TCMS module is connected with the MVB communication module through a TCU (TCMS communication unit), the train level signal (DC 110/24V) module is connected with the level signal acquisition and processing module through a main control signal, a door closing signal, a zero-speed signal and a thirty kilometer signal, and the train power supply module supplies DC110V to the power supply module.

PIS operation screen PISM is connected with the marshalling net switch module through gigabit Ethernet X1, carriage controller CCU is connected with the marshalling net switch module through gigabit Ethernet X2, cab camera is connected with the forwarding, storing and multicasting module of digital audio through hundred mega Ethernet X3, end screen display is connected with the video recording storage module through hundred mega Ethernet X1, microphone/OCC is connected with the audio processing module through analog audio input, and loudspeaker is connected with the audio processing module through analog audio output.

The networked vehicle-mounted broadcasting system and the implementation method thereof adopt the full Ethernet topology and cooperate with the digital multimedia terminal; the low-power consumption terminal equipment adopts POE power supply (IEEE 802.3 af/at) technology; the exchanger adopts Dynamic Host Configuration Protocol (DHCP) to automatically allocate the IP address of the terminal equipment; a VoIP technology is adopted to realize visual digital intercom; based on gigabit Ethernet communication technology, an embedded processor is used as a core, an all-Ethernet topology, a digital multimedia terminal and an integrated control host are adopted, three subsystems and Ethernet are integrated, the system architecture is simplified, POE power supply and DHCP technology is used by terminal equipment, and the difficulty of system design, development, construction, debugging and maintenance is reduced;

Based on the Ethernet construction, the terminal equipment is all digitized and is accessed into the Ethernet; the system host PISC should adopt a three-layer switch, the CCU adopts a two-layer switch, and the terminal equipment is all digitized and connected into the ethernet; the train-level Ethernet adopts gigabit network to support two networking modes of link aggregation or ring topology; in the digital PIS, all terminals adopt Ethernet communication, and considering the wiring and debugging of the system, all terminals preferably adopt DHCP to set IP and the power supply adopts network cable to supply power; the passenger room LCD display and the passenger guiding display (TGS) are distributed on two sides of a carriage, are cascaded in a hand-in-hand mode, and a single terminal device is required to be provided with two Ethernet interfaces, and the two interfaces have a Bypass function; the vehicle-mounted broadcasting system is used for carrying out function division based on terminal equipment and mainly comprises the functions of broadcasting stations, intercom contact, information display, video storage, monitoring inquiry and the like; when the system operates normally, the main control end PISC is responsible, the slave control end PISC is in a hot standby state, and the main control end is mainly responsible for the data synchronization function.

A networked vehicle-mounted broadcasting system comprises the following steps of;

The OCC manual broadcasting step: the control center OCC can be wirelessly connected to the PIS system through the train-ground in the operation process to manually broadcast passengers;

step 1, a control center OCC sends an OCC manual broadcast control instruction to two ends PISC through Ethernet connection PISC;

step2, after receiving the control instruction, the main control terminal PISC switches the broadcasting mode to the OCC manual broadcasting state and interrupts the current broadcasting content;

Step 3, the main control terminal PISC sends the artificial broadcasting digital signal sent by the OCC to the passenger room CCU through the Ethernet;

Step 4, after receiving the digital audio signal, the guest room CCU carries out digital power amplification and drives a guest room loudspeaker to play;

And step 5, after the manual broadcasting language is played, the control center OCC sends a command for canceling the manual broadcasting, and the broadcasting mode of the main control end PISC is restored to the state before the manual broadcasting is executed.

Manual broadcasting: the driver directly triggers the 'manual broadcasting' function through the PTT key of the handheld microphone of the control console or the side walls at both sides; comprises the following steps of;

Step 1, a driver directly triggers a 'manual broadcasting' function by operating a console or side wall microphones on two sides and pressing PTT keys over 2S for a long time;

Step 2, after receiving the instruction of "manual broadcast", the main control terminal PISC switches the broadcast mode to the OCC manual broadcast state and interrupts the current broadcast content;

Step 3, the hand-held MIC modulates and converts the collected voice signals into digital audio signals through PCM (pulse code modulation);

step 4, the main control terminal PISC sends the artificial broadcast audio signal sent by the OCC to the passenger room CCU through the Ethernet;

Step 5, after receiving the digital audio signal, the guest room CCU carries out digital power amplification and drives a guest room loudspeaker to play;

and 6, the driver releases the PTT key 2S and automatically cuts off the 'manual broadcasting' function, and the broadcasting mode of the main control terminal PISC is restored to the 'manual broadcasting' state before execution.

An OCC emergency broadcasting step: in a full-automatic driving mode, when a train encounters an emergency (such as a fire disaster, serious faults and the like), the control center OCC can be wirelessly connected to the PIS system through the train ground in the operation process to carry out emergency broadcasting on passengers; comprises the following steps of;

Step 1, a control center OCC sends an OCC emergency broadcast control instruction to two ends PISC through an Ethernet connection PISC;

step 2, the main control terminal PISC receives the operation instruction, and switches the broadcasting mode to the OCC emergency broadcasting state by judging the broadcasting priority and the broadcasting volume level;

PISC decodes the corresponding emergency broadcast voice file, and sends the decoded emergency broadcast voice file to a passenger room CCU through an Ethernet;

the CCU decodes the digital audio signal after receiving the digital audio signal, and broadcasts the decoded audio signal after processing the audio signal through the analog channel.

An emergency broadcasting step: when the train encounters an emergency (such as a fire disaster, serious faults and the like), a driver can operate PISM, and the emergency broadcasting operation broadcasts a voice file which is recorded in advance by the main control end PISC and contains contents such as command guiding or apology soothing to passengers; comprises the following steps of;

step 1, entering an emergency broadcast sub-interface through PISM operation, and selecting a corresponding emergency broadcast item to confirm playing;

Step 2, the main control terminal PISC receives the operation instruction and judges the broadcasting priority and the broadcasting volume level;

Step 3, PISC, decoding the corresponding emergency broadcast voice file, and transmitting the decoded emergency broadcast voice file to a passenger room CCU through an Ethernet;

and 4, decoding after receiving the digital audio signal, and broadcasting the decoded audio signal after processing the digital audio signal through an analog channel.

Full-automatic station reporting;

In a full-automatic stop reporting mode, PISC in a main control state receives an ATO stop reporting control instruction forwarded by a TCMS, and performs stop reporting on passengers according to preset stop reporting logic, wherein the stop reporting content is a digital voice file which is recorded in advance and stored in PISC; comprises the following steps of;

Step 1, selecting a full-automatic station reporting mode (ATO) through operation of PISM;

The main control terminal PISC receives the real-time signal sent by the TCMS system, analyzes and generates broadcasting control and voice file calling instructions of broadcasting stations, and judges the broadcasting priority and broadcasting volume level;

step 2, PISC decodes the corresponding voice file of the "departure report station" and the "arrival report station", and sends the decoded voice file to the guest room CCU through the Ethernet;

And step 3, the CCU receives the digital audio signals and decodes the digital audio signals, and the decoded audio signals are broadcasted after being processed through an analog channel.

And (3) standby broadcasting: by arranging an independent analog audio bus, an analog handheld microphone and a loudspeaker, a whole set of standby broadcasting scheme is formed, and when the digital broadcasting function cannot work normally, a cab can call a passenger room through the standby microphone to complete the manual broadcasting function;

The driver presses the PTT side key of the MIC, the key signals are collected by the analog power amplifier, each analog power amplifier device is controlled by the vehicle audio bus, and the audio processing channel is opened; the analog power amplifier of each guest room connects the audio frequency to the loudspeaker line of guest room at ordinary times, the driver can call the guest room through the microphone, finish the artificial broadcasting function; the audio channel is disconnected after the PTT side key of the MIC is released.

Semi-automatic station reporting step: in a semi-automatic stop reporting mode, the main control state PISC carries out a stop reporting or a stop arrival reporting on passengers by collecting signals provided by trains, and the stop reporting content is a digital voice file which is recorded in advance and stored in PISC; comprises the following steps of;

Step 1, a train signal system sends head/tail signals, vehicle door closing signals, zero speed signals, thirty kilometers signals or mileage signals to a main control side PISC in real time;

Step 2, PISC collects the signals to judge the current running state of the train, analyzes and generates a broadcasting control instruction of broadcasting according to preset broadcasting logic, and judges the broadcasting priority and the broadcasting volume level;

step 3, PISC decodes the corresponding voice file of the "departure report station" and the "arrival report station", and sends the decoded voice file to the passenger room CCU through the Ethernet;

OCC manual station reporting step: in an unmanned full-automatic driving operation mode, the OCC can manually specify the stop reporting content, and the PISC in the main control state starts or stops the stop reporting according to the stop reporting code provided by the OCC, wherein the stop reporting content is a digital voice file which is pre-recorded and stored in PISC; comprises the following steps of;

Step 1, in a full-automatic driving mode, the OCC sends a broadcasting control instruction to a main control terminal PISC through the Ethernet;

Step 2, after receiving the broadcasting control instruction, the main control terminal PISC analyzes and generates broadcasting control and voice file calling instructions, and judges broadcasting priority and broadcasting volume level;

Step 3, PISC decodes the corresponding voice files of the departure report station and the arrival report station, and sends the decoded voice files to the passenger room CCU through the Ethernet;

Manual station reporting step: the driver can specify the stop reporting content through PISM interface, and PISC starts or stops stop reporting according to the stop reporting code provided by PISM in the main control state, wherein the stop reporting content is a digital voice file which is prerecorded and stored in PISC; comprises the following steps of;

Step 1, through carrying out corresponding operation on PISM, manually selecting a train running interval, a running direction, station information and station reporting time, generating a broadcast control instruction, and sending the broadcast control instruction to a main control end PISC through an Ethernet;

The broadcast priority levels are arranged from high to low as follows:

(1) The OCC is broadcasted manually;

(2) An OCC emergency broadcast;

(3) OCC manual station reporting;

(4) Manually broadcasting;

(5) Emergency broadcasting;

(6) Manually reporting the station;

(7) Full automatic announcement radio (ATO);

(8) Semi-automatic station reporting; the talkback priorities are arranged in the following order from high to low:

1) The OCC is used for emergency intercom with passengers;

2) Emergency intercom between driver and passenger;

3) And the driver talkbacks with the driver.

Because the manual broadcasting and intercom system uses the same hand-held microphone, the priorities of two functions are required to be considered; wherein, the priority of manual broadcasting and driver intercom can be set as:

1) Manual broadcast priority;

2) The talkback priority of the driver;

3) Equivalent grade.

Broadcast station priority: the broadcasting station reporting function can be divided into different priority levels, the high-level broadcasting station or station reporting can interrupt the low-level broadcasting station or station reporting, when the high-level communication requirement arrives, the broadcasting low-level communication should be interrupted immediately, the low-level broadcasting station or station reporting cannot interrupt the high-level broadcasting station or station reporting, and the low-level broadcasting station or station reporting can be triggered only after the high-level broadcasting station or station reporting is ended; the broadcast priority judgment is realized by broadcast control software, the software presets priority judgment logic, and when a broadcast instruction is received, the corresponding operation is executed after the priority judgment by the preset logic.

Volume automatic adjustment: the digital PIS can collect a passenger room noise value through a passenger room emergency alarm or a noise detection device, and perform corresponding operation according to the collected noise value, so that automatic adjustment of the output volume of the station reporting audio is realized, the output volume of a passenger room loudspeaker is always 5-10 dB higher than the indoor noise, but the output volume of the loudspeaker is not higher than 95dB at any time;

The automatic adjustment of the volume is performed by guest room equipment, and each guest room adjusts the volume according to the noise value of the guest room; comprises the following steps of;

Step 1, the system collects real-time noise conditions in a carriage through a passenger emergency alarm in the carriage, the alarm converts an analog noise signal into a digital noise value through audio processing and operation, and the noise value is sent to a CCU;

step 2, after receiving the noise value, the CCU adjusts the station reporting sound value sent by the main control terminal PISC according to the preset corresponding relation between the noise value and the output sound value;

And 3, the CCU controls and outputs the stop-reporting audio according to the adjusted volume value and plays the stop-reporting audio through a passenger room loudspeaker.

Volume configuration: the system-related volume can be set by a PTU (portable test unit); the volume to be set mainly includes:

Automatic broadcast volume; the volume of the manual broadcast; OCC broadcast volume; media sound volume; monitoring volume in the guest room; talkback speaker volume; MIC volume of intercom; MIC volume of alarm; the volume of the horn of the alarm.

Monitoring broadcasting stations: in order to facilitate the driver to know whether the broadcasting state in the passenger room is normal, the driver/OCC/BCC can monitor the broadcasting station broadcasting, the manual broadcasting and the OCC broadcasting in the passenger room, and the media accompanying sound broadcasting should not be in the monitoring range.

The OCC and passenger emergency intercom step: in an unattended automatic driving mode, when an emergency situation occurs in a passenger room or an emergency occurs, a passenger can press an alarm button of the emergency alarm in the passenger room according to the use instruction on the emergency alarm, and can realize intercom communication with an OCC control center through a built-in intercom device beside the button; comprises the following steps of;

step 1, a passenger initiates a request for communicating with a driver by triggering an alarm button of an emergency alarm (PEI);

step 2, PEI sends an alarm instruction to CCU through an Ethernet bus;

step 3, after receiving the alarm instruction, the CCU sends a call request instruction to the main control side PISC through the ethernet bus after processing;

step 4, after receiving the call request instruction, the main control side PISC comprehensively judges the alarm information of all the current alarms, sorts the alarm information according to the time sequence, and then sends the alarm call request to PISM through Ethernet communication; PISC sends the alarm call request to the OCC control center

Step 5, PISM, popping up an alarm picture on the display screen after receiving an alarm call request instruction;

Step 6, the OCC performs on (or hang-up) operation, and sends an operation instruction to the main control terminal PISC;

Step 7, after receiving the alarm on (or hang-up) instruction, the main control terminal PISC processes the alarm on (or hang-up) instruction and sends the alarm on (or hang-up) instruction to the CCU through the ethernet bus;

step 8, after receiving the alarm on instruction, the CCU of the carriage where the alarm firstly alarms establishes an audio channel, and meanwhile, sends an indicator lamp control instruction to the PEI, and full duplex communication can be carried out between the PEI and the main control terminal PISC;

step 9, the CCU corresponding to the PEI in the queuing state sends a call busy instruction to the PEI, and a PEI busy indicator lamp is lightened;

And step 10, hanging up operation is carried out through 0CC or reset operation is carried out on PEI to finish the current call, and the system is used for switching on the next queuing alarm according to the flow until all the alarms triggering the alarm are hung up.

The emergency intercom step of the driver and the passenger comprises the following steps: in the driving mode of taking the passenger by the driver, when an emergency situation or an emergency occurs in the passenger room, the passenger can press the alarm button of the emergency alarm in the passenger room according to the use instruction on the emergency alarm, and the intercom with the driver is realized through the built-in intercom device beside the button; comprises the following steps of;

step 1, a passenger initiates a request for communicating with a driver by triggering a PEI alarm key of an emergency alarm;

step 2, PEI sends an alarm instruction to CCU through an Ethernet bus;

step 4, after receiving the call request instruction, the master control side MCU comprehensively judges the alarm information of all the current alarms, sorts the alarm information according to the time sequence, and then sends the alarm call request to PISM through Ethernet communication;

step 6, the alarm is turned on by operating PISM, and PISM sends an alarm turn-on instruction to a main control end PISC;

step 7, after receiving the alarm switch-on instruction, the main control terminal PISC processes the alarm switch-on instruction and sends the alarm switch-on instruction to the CCU through the Ethernet bus;

And 10, ending the current call by hanging up PISM or resetting PEI, and switching on the next queuing alarm according to the flow by the system until all alarms triggering the alarm are switched on.

The step of driver-to-driver intercommunication: the cabs at the two ends of the train can carry out full duplex voice communication through the handheld microphone, and the master control end or the slave control end can initiate or end intercom; after one party initiates intercom, the other party can directly carry out conversation without confirmation; when the digital voice automatic broadcasting is carried out on the train, the communication intercom function of the driver can still be normally realized; comprises the following steps of;

step1, performing operation triggering intercom through PISM;

step 2, PISM sends an intercom instruction through an Ethernet bus;

step 3, the intercom initiating side PISC sends an intercom calling instruction to the opposite side PISC through an Ethernet bus;

step 4, receiving an intercom calling instruction by the opposite side PISC, judging the broadcasting priority and intercom volume level, and establishing an audio channel;

step 5, the two ends PISC of the train encode and decode the two-end intercom MIC audio signals respectively, and realize full duplex intercom conversation through Ethernet transmission;

Step 6, finishing the intercom conversation by operating any one side PISM;

and 7, transmitting the talkback command through the same path as the talkback request, and cutting off the audio path.

Intercom recording: when the intercom function is activated, the system automatically records and stores the conversation content in the intercom process, and the recorded voice file can be downloaded and played through special software or tools; comprises the following steps of;

step 1, when an intercom function is activated, a main control PISC automatically collects intercom audio signals and records voice;

Step 2, naming the voice file according to the corresponding rule and storing the voice file in the main control terminal PISC;

and 3, downloading and playing back the recording file through the PTU tool by using the Ethernet connection PISC/CCU.

A networked vehicle-mounted broadcasting system is characterized in that a vehicle head cab and a vehicle tail cab are respectively provided with a control unit PISC, one control unit PISC works by default, the other control unit PISC is hot standby, and the other control unit is a slave control unit; comprises the following steps of;

step 1, under normal conditions, only one end cab PISC is in a main control state, the main control state is determined by the fact that the local end PISC receives effective operation, the effective operation is only two types of the PISM touch operation and the train head-tail signal key activation, and the key activation priority is larger than PISM touch operation;

Step 2, in the state that the cabs PISC at both ends do not receive the head-tail signal activation, the system is powered on to default that the TC1 end PISC is a system master control end, the TC2 end PISC is a slave control end, when the communication between both ends is normal, the master control state of both ends PISC can be switched through the operation of both ends PISM, the master control end PISC sends the master control state to the other end PISC, and the other end PISC is changed into the slave control end; when communication at two ends is interrupted, PISC which can normally communicate with PISM can be switched to a main control end through PISM, and PISC which can not normally communicate with the other end is unchanged until the next effective operation (switching through PISM or head-to-tail signal activation);

Step 3, when the cabs PISC at the two ends have the active state of receiving the head-tail signals, the cab PISC at the end of receiving the active state of only the head-tail signals is the master control end, and after the head-tail signals disappear, the master control state disappears, and the master control end automatically becomes the slave control end; when the communication between the two ends is normal, the master control end PISC sends the master control state to the other end PISC, and the other end PISC becomes a slave control end and cannot rob away the master control state; when the communication between the two ends is interrupted, the active end of the received head and tail signals is the main control end, and the active end of the non-received head and tail signals is not the slave control end until the next effective operation (switching or head and tail signal activation through PISM).

A networked vehicle-mounted broadcasting system comprises a terminal information display: the terminal display screen (EDD) is positioned at the top end of the outside of the head and the tail of the train and is used for prompting the terminal information of the running of the train to passengers such as a platform; comprises the following steps of;

step 1, setting a train operation interval by performing corresponding operation on a main control terminal PISC through PISM/OCC;

Step 2, the main control terminal PISC sends the terminal information (Chinese character area code) to the EDDs on both sides;

And 3, receiving and displaying the EDDs at the two sides according to the instruction.

A networked vehicle-mounted broadcasting system comprises a station reporting information display: external Information Display Screens (BIDs) are positioned on two sides outside the train, and prompt passengers at the platform of next station information of the train operation; in-car Information Display Screens (EIDs) are positioned at two ends in the car and display broadcasting voice words or emergency messages to passengers in the carriage; comprises the following steps of;

Step 2, the main control terminal PISC sends the station report information (Chinese character location code) to BID/EID;

and 3, receiving and displaying the BID/EID according to the instruction.

A networked vehicle-mounted broadcasting system, comprising map information display: a guide display (TGS) is arranged above the passenger compartment door and used for prompting train operation information to passengers in the passenger compartment, and the TGS receives the operation information sent by the main control state PISC and displays the operation information according to instructions; the interface information of the TGS can be stored locally in the equipment and is updated in batches remotely through a network; or in PISC, TGS is responsible for decoding the display, and only the interface stored in the host needs to be updated at the time of updating.

The map information display mainly includes the following:

A train operation section;

The running direction of the train;

The door opening side direction of the next station of the train;

The information of the current station and the next station of the train operation;

the arrival time of the front station;

a networked vehicle-mounted broadcasting system comprises a train transfer station and transfer line information, and comprises the following steps of;

Step 1, a main control terminal PISM is operated through PISM/OCC to set a train running interval, a train running direction, station information and a door opening side direction;

Step 2, the main control terminal PISC judges and generates a control instruction required by TGS display according to the current running state of the train, and sends the control instruction to the passenger room CCU through the Ethernet, and the CCU forwards the control instruction to the TGS;

and step 3, after receiving the control instruction, the TGS carries out corresponding instruction.

A networked on-board broadcast system comprising a media information display: the media playing comprises network playing and local playing; comprises the following steps of;

(1) And (3) network playing:

The system is started to default to a network playing mode, a guest room LCD display screen plays video images input by a ground PIS system, and a guest room loudspeaker plays media accompanying sound corresponding to the video files;

(2) And (3) local play:

when the control center fails or network communication is interrupted and the system detects illegal invasion, the system automatically switches to a local play mode, PISC directly transmits a digital film source pre-stored in a hard disk to a guest room LCD display in an audio and video stream mode through the Ethernet.

A networked on-board broadcast system comprising an operation information display: the station service information display area of the guest room LCD display screen is used for displaying the station information of a starting station, a destination station and a next station, transfer and other service information according to the train running line and the train running direction; the report station information text prompt area can scroll display report station broadcast or emergency broadcast content in a text form; comprises the following steps of;

step 2, the main control terminal PISC judges and generates a control instruction required by LCD display according to the current running state of the train, and sends the control instruction to the passenger room CCU through the Ethernet, and the CCU is forwarded to the LCD;

and step 3, the LCD receives the control instruction and then carries out corresponding instruction.

A networked on-board broadcast system comprising OCC emergency text delivery: when the OCC issues the emergency information, the guest room LCD display can be automatically switched, the emergency information is issued according to a full-screen display mode, and the original playing can be automatically restored after the emergency information is released.

A networked on-board broadcast system comprising video storage: the real-time video images of all channels can be stored in a storage medium of a video monitoring server in a specified format and a specified path at the same time of display, and are named according to a certain rule; the storage capacity of the storage medium meets the storage requirement of the monitoring video of all channels of the whole vehicle for more than 90 days, and the video image storage is performed in a cyclic coverage mode; video files in the storage hard disk may be downloaded over PISC/CCU network interfaces using PTU tools.

A networked vehicle-mounted broadcasting system comprises vehicle-mounted real-time monitoring: the two ends PISM can display the monitoring video of the cab or any carriage in real time, and can realize single-picture and four-picture switching, polling or manual channel selection display; comprises the following steps of;

step 1, an image signal of a monitoring area is converted into a digital signal by an IPC (internet protocol camera), and then the digital signal is encoded and compressed to form a digital video stream; PISC/CCU transmitting the digital video stream to each cab/guest room via ethernet;

step 2, PISC/CCU receives a digital video stream from the ethernet and sends it to both ends PISM;

step3, decoding the received digital video stream by two ends PISM to generate video images and displaying the video images on a PISM display screen;

and 4, realizing single-picture and four-picture display switching and picture polling and stopping polling through PISM operations.

A networked vehicle-mounted broadcasting system comprises OCC real-time monitoring: the video pictures can be transmitted to a ground control center (OCC/BCC/TCC/station comprehensive control and the like) in real time, and the ground control center can view video images in real time; in a full-automatic driving mode, when the system triggers an alarm, an alarm picture is wirelessly transmitted to the OCC through a vehicle ground, so that the OCC can conveniently check the alarm picture in real time.

A networked vehicle-mounted broadcasting system comprises a vehicle-mounted video inquiry: the digitized PIS may query video recordings through the cab PISM, and the retrieved recordings may be used for video playback; the video retrieval interface can be accessed by touch operation on both ends PISM, and the recorded video file can be retrieved and played back.

A networked vehicle-mounted broadcasting system comprises an OCC video inquiry: when a terminal of a ground control center (OCC/BCC/TCC, etc.) inquires video recordings, PISM processes the inquiry request, and the searched recordings can be used for video playback and video downloading.

A networked vehicle-mounted broadcast system, comprising alarm linkage: when the passenger triggers the emergency alarm to be turned on, the video picture of PISM is automatically switched to a video camera channel on the same side of the carriage where the alarm event is located and the on-position alarm; at the same time of linkage triggering, the recording speed of 8 frames per second of video images of two channels of an alarm carriage is converted into the recording speed of 25 frames per second, and video images within 10 minutes before an alarm event in a hard disk buffer zone occurs are recorded in the hard disk event zone at the speed of 25 frames per second, and are named according to a certain naming rule; after the alarm event is finished, the video image still needs to be stored for 10 minutes at the speed of 25 frames per second; the relevant video recordings of alarm events should be saved for at least 72 hours;

when the alarm is turned on, PISC receives the alarm information and then realizes the function of switching the video image display channels and converting the stored image frame rate.

A networked vehicular broadcast system comprising a data record: comprises the following steps of;

Step 1, in order to judge that the faults occurring in the actual running process of the system are caused by the problems of the system or misoperation of a driver, the system can record related operations performed on the system and store the related operations in a text form;

step 2, in order to conveniently grasp the demarcation of the fault reason, the system should be capable of recording and storing the communication data of an external system, and mainly comprises train level signals and the communication data between the train level signals and TCMS, OCC, ground PIS and the like;

Step 3, the system records and stores the communication data among the internal main equipment so as to facilitate system fault investigation and perfect communication mechanism;

Step 4, the data recording function requires that the related devices in the system should keep time synchronization, so the system design should fully consider and realize the function of time calibration among the main devices of the system.

A networked on-board broadcast system comprising an IP address auto-assignment: the terminal equipment of the direct connection system backbone network is automatically allocated with an IP address by using DHCP, which comprises PISM, PAU, EDD, CAM equipment; the IP address is determined by a device address dial switch or address shorting line for the host device PISC, CCU, etc.

The IP address is determined for the terminal devices connected through the branch network through the device address dial switch or the address shorting line, including LCD, TGS, EID, BID and the like.

A networked vehicular broadcast system comprising device status detection: and checking the fault condition of each sub-device of the PIS system through data communication at two ends PISM, including on-line state, software and hardware version, fault record and the like, and when the device breaks down, PISC generates fault information and sends the fault information to two ends PISM to be displayed.

After the system is powered on, all host devices have a startup self-diagnosis function, and fault information is automatically sent to hosts at two ends PISC.

By manipulating both ends PISM, a status detection sub-interface is entered.

The 'on-line status', 'software version', 'hardware version', 'fault record' or 'repair description' is selected to see the status of each device.

A networked vehicle-mounted broadcasting system comprises the following sub-components and basic parameters.

The Passenger Information System Controller (PISC)/guest room Communication Controller (CCU), PISC/CCU adopts a 19 inch 3U standard European standard case, two products are planned uniformly, broadcast, media, monitoring and a switch are integrated, each unit inside the products adopts a modularized design, the reusability of the units is considered, and different product functions are realized by configuring different back boards and units.

An LCD display:

The LCD displays comprise a passenger information system operation screen (PISM), a passenger information display (TGS) and a passenger room media television (LCD); the PISM is located on a cab console, is an operation terminal of the PIS system, is used for performing operation control and display functions on a system host (PISC), and the TGS and the LCD are located on a passenger compartment, are display terminals of the PIS system, and are used for providing train operation information and the like for passengers.

Passenger information system operation screen (PISM):

PISM integrates the functions of a conventional project broadcast control box and a video monitoring display, and is an operation terminal for controlling and setting a passenger information system; the equipment is arranged on cab operation tables at two ends of a train, and functions of driver contact intercom, broadcasting station report, monitoring inquiry and the like can be realized through PISM touch operation; meanwhile, PISM display interfaces can display the current running state of the train, monitoring images, related operations and running states of system equipment, and PISM adopts a 14-inch display screen and a touch screen.

Ride control information display (TGS):

The TGS is used for indicating station information to passengers, and comprises a running direction, a front station, a terminal station and a door opening side indicator lamp; the TGS is connected to the switch unit of the CCU through an Ethernet port, receives the related signals sent by the CCU, and controls the corresponding site information to be displayed.

Passenger compartment media television (LCD):

The passenger room LCD display (LCD) adopts a 17/19/21 inch display screen, is arranged on the side wall of the passenger room carriage, is one of the most important terminal display devices of the passenger information display subsystem, and is an important window for providing media entertainment information and train operation service information for passengers.

An LED display:

the LCE display comprises an end station display (EDD), an off-Board Information Display (BID) and an in-car information display (EID), is a PIS system LED display terminal, and can automatically adjust display contents according to different IP addresses, including a train operation end station, a next station, broadcasting words, emergency information and the like.

Network camera IPC:

The network camera comprises a rearview camera, a driving recording camera and a passenger room camera; the color network camera with fixed focal length is used for monitoring the conditions of a cab and a guest room, and the color network camera is used for collecting image signals through a photosensitive module, generating a network video code stream through a video coding module and uploading the network video code stream to an Ethernet.

Cab/guest room webcam:

Driving recording camera:

The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.

Claims

1. A method for realizing network train broadcasting is characterized by comprising the following steps of;

Manual broadcasting: the driver directly triggers the 'manual broadcasting' function through the PTT key of the handheld microphone of the control console or the side walls at both sides;

An emergency broadcasting step: when a train encounters an emergency, and a fire disaster and serious faults occur, a driver operates PISM, and the emergency broadcasting operation broadcasts a voice file which is recorded in advance by a main control end PISC and contains command dredging or apology soothing contents to passengers;

full-automatic station reporting step: in a full-automatic stop reporting mode, PISC in a main control state receives an ATO stop reporting control instruction forwarded by a TCMS, and performs stop reporting on passengers according to preset stop reporting logic, wherein the stop reporting content is a digital voice file which is recorded in advance and stored in PISC;

the driver presses the PTT side key of the MIC, the key signals are collected by the analog power amplifier, each analog power amplifier device is controlled by the vehicle audio bus, and the audio processing channel is opened; each passenger room analog power amplifier is used for connecting audio to a passenger room loudspeaker line at ordinary times, and a driver speaks into the passenger room through a microphone to complete a manual broadcasting function; after the PTT side key of the MIC is released, the audio channel is disconnected;

Manual station reporting step: the driver designates the stop report content through PISM interface, PISC starts or stops stop report according to the stop report code provided by PISM in the main control state, and the stop report content is a digital voice file pre-recorded and stored in PISC;

The control center OCC sends an OCC emergency broadcast control instruction to the two ends PISC through the Ethernet connection PISC; the main control terminal PISC receives the operation instruction and switches the broadcasting mode to the OCC emergency broadcasting state by judging the broadcasting priority and the broadcasting volume level; PISC decodes the corresponding emergency broadcast voice file, and sends the decoded emergency broadcast voice file to a passenger room CCU through an Ethernet; the CCU receives the digital audio signal, decodes the digital audio signal, processes the decoded audio signal through an analog path, broadcasts the decoded audio signal,

The OCC emergency broadcasting step further includes an OCC and passenger emergency intercom step: in an unattended automatic driving mode, when an emergency situation occurs in a passenger room or an emergency occurs, a passenger can press an alarm button of the emergency alarm in the passenger room according to the use instruction on the emergency alarm, and can realize intercom communication with an OCC control center through a built-in intercom device beside the button;

the passenger initiates a call request with the driver by triggering a PEI alarm button of the emergency alarm;

the PAU sends an alarm instruction to the CCU through an Ethernet bus;

after receiving the alarm instruction, the CCU processes the alarm instruction and sends a call request instruction to the main control side PISC through the ethernet bus;

After receiving the call request instruction, the main control side PISC comprehensively judges the alarm information of all the current alarms, sorts the alarm information according to the time sequence, and then sends the alarm call request to PISM through Ethernet communication; PISC sends the alarm call request to the OCC control center

PISM pops up an alarm picture on the display screen after receiving an alarm call request instruction;

the OCC performs on-off or hang-up operation and sends an operation instruction to the main control terminal PISC;

after receiving the alarm on or off instruction, the main control terminal PISC processes the alarm on or off instruction and sends the alarm on or off instruction to the CCU through the Ethernet bus;

The CCU of the carriage where the alarm firstly alarms receives the alarm on instruction and then establishes an audio channel, and meanwhile, an indicator lamp control instruction is sent to PEI, so that full duplex communication can be carried out between PEI and the main control terminal PISC;

The CCU corresponding to the PEI in the queuing state sends a call busy instruction to the PEI, and a PEI busy indicator lamp is lightened;

The current call is ended by hanging up the alarm through 0CC or resetting the PEI, the system is connected with the next queuing alarm according to the flow until all the alarms triggering the alarm are hung up,

The semi-automatic station reporting step further comprises the following steps; the train signal system sends head/tail, door closing, zero speed, thirty kilometers or mileage or speed signals to the main control side PISC in real time; PISC collecting the signals to judge the current running state of the train, analyzing and generating a broadcasting control instruction of broadcasting according to preset broadcasting logic, and judging the broadcasting priority and the broadcasting volume level; PISC decodes the corresponding voice file of the "departure report station" and "arrival report station", and sends the decoded voice file to the passenger room CCU through the Ethernet; the CCU receives the digital audio signal, decodes the digital audio signal, processes the decoded audio signal through an analog path, broadcasts the decoded audio signal,

The broadcast priority levels are arranged from high to low as follows:

(1) The OCC is broadcasted manually;

(2) An OCC emergency broadcast;

(3) OCC manual station reporting;

(4) Manually broadcasting;

(5) Emergency broadcasting;

(6) Manually reporting the station;

(7) Full-automatic station broadcasting ATO;

(8) Semi-automatic station reporting, and the talkback priority is arranged from high to low according to the following sequence:

1) The OCC is used for emergency intercom with passengers;

2) Emergency intercom between driver and passenger;

3) The driver talkbacks with the driver;

The manual broadcasting and intercom system uses the same hand-held microphone, wherein the priority of manual broadcasting and intercom by a driver is set as follows:

1) Manual broadcast priority;

2) The talkback priority of the driver;

3) At the same level as the first one,

The emergency intercom step of the driver and the passenger comprises the following steps: when an emergency situation or an emergency occurs in a passenger room in a driver on-duty driving mode, a passenger presses an alarm button of the emergency alarm in the passenger room according to a use instruction on the emergency alarm, and an intercom conversation with the driver is realized through an embedded intercom device beside the button;

The passenger initiates a call request with the driver by triggering a PEI alarm button of the emergency alarm; the PAU sends an alarm instruction to the CCU through an Ethernet bus; after receiving the alarm instruction, the CCU processes the alarm instruction and sends a call request instruction to the main control side PISC through the ethernet bus; after receiving the call request instruction, the MCU at the main control side comprehensively judges the alarm information of all the current alarms, sorts the alarm information according to the time sequence, and then sends the alarm call request to PISM through Ethernet communication; PISM pops up an alarm picture on the display screen after receiving an alarm call request instruction; by operating PISM to turn on the alarm, PISM sends an alarm turn-on instruction to the master control terminal PISC; the main control terminal PISC processes the alarm on command after receiving the alarm on command and sends the alarm on command to the CCU through the Ethernet bus; the CCU of the carriage where the alarm firstly alarms receives the alarm on instruction and then establishes an audio channel, and meanwhile, an indicator lamp control instruction is sent to PEI, so that full duplex communication can be carried out between PEI and the main control terminal PISC; the CCU corresponding to the PEI in the queuing state sends a call busy instruction to the PEI, and a PEI busy indicator lamp is lightened; the current call is ended by hanging up PISM or resetting PEI, and the system will switch on the next queuing alarm according to the above procedure until all alarms triggering the alarm are switched on.

2. A networked vehicle-mounted broadcasting system according to the method of claim 1, characterized by adopting an all-ethernet topology and cooperating with a digital multimedia terminal; the low-power-consumption terminal equipment adopts a POE power supply IEEE 802.3 af/at technology; the exchanger adopts dynamic host setting protocol DHCP to automatically distribute the IP address of the terminal equipment; a VoIP technology is adopted to realize visual digital intercom; based on gigabit Ethernet communication technology, with embedded processor as core, the system adopts full Ethernet topology, digital multimedia terminal, integrated control host, integrates three subsystems and Ethernet, and terminal equipment uses POE power supply and DHCP technology.

3. A networked vehicle-mounted broadcasting system according to claim 2, wherein the terminal devices are all digitized and connected to the ethernet network based on ethernet network establishment; the system host PISC adopts a three-layer switch, the CCU adopts a two-layer switch, and the terminal equipment is all digitized and connected into the Ethernet; the train-level Ethernet adopts a gigabit network and supports two networking modes of link aggregation or ring topology; in the digital PIS, all terminals adopt Ethernet communication, and considering wiring and debugging of a system, all terminals adopt DHCP to set IP and power supply adopts network cable to supply power; the passenger room LCD display and the guide display TGS are distributed on two sides of a carriage, are cascaded in a hand-in-hand mode, and a single terminal device is required to be provided with two Ethernet interfaces, and the two interfaces have a Bypass function.

4. The networked vehicle-mounted broadcasting system according to claim 2, wherein the vehicle-mounted broadcasting system performs function division based on terminal equipment, and comprises broadcasting station broadcasting, intercom contact, information display, video recording storage and monitoring inquiry functions; when the system operates normally, the work is responsible for the master control end PISC, and the slave control end PISC is in a hot standby state and is responsible for the data synchronization function.

5. The networked vehicle-mounted broadcasting system according to claim 2, wherein a PISC is installed in each of the front and rear cabs, one PISC works as a master control end and the other PISC is a slave control end by default;

Under normal conditions, only one end cab PISC is in a main control state, the main control state is determined by the fact that the local end PISC receives effective operation, the effective operation is only two types of touch operation through PISM and key activation of signals at the head and the tail of a train, and the key activation priority is greater than PISM touch operation;

When the cabs PISC at the two ends do not receive the head-tail signal activation state, the system is powered on to default that the TC1 end PISC is a system master control end, the TC2 end PISC is a slave control end, when the communication between the two ends is normal, the master control state of the two ends PISC can be switched through the operation of the two ends PISM, the master control end PISC sends the master control state to the other end PISC, and the other end PISC is changed into the slave control end; when communication at two ends is interrupted, PISC which can normally communicate with PISM can be switched to a main control end through PISM, PISC which can not normally communicate with the other end is unchanged until effective operation is next time, and switching is performed through PISM or head-to-tail signals are activated;

when the cabs PISC at the two ends are in the state of receiving the head-tail signal activation, the cab PISC at the end of receiving the head-tail signal activation is taken as the master control end, and after the head-tail signal disappears, the master control state disappears, and the master control end automatically becomes the slave control end; when the communication between the two ends is normal, the master control end PISC sends the master control state to the other end PISC, and the other end PISC becomes a slave control end and cannot rob away the master control state; when the communication between the two ends is interrupted, the active end of the received head and tail signals is the main control end, and the active end of the non-received head and tail signals is not the slave control end until the next effective operation, and the switching or the head and tail signal activation is carried out through PISM.