A data acquisition method for an onboard safety platform based on real-time channel switching

Abstract

This invention discloses a data acquisition method for an in-vehicle safety platform based on real-time channel switching, relating to the field of in-vehicle safety platform data acquisition technology. The method includes the following steps: S1, after the computing board starts, it loads all external devices and channel configurations; S2, after the communication board starts, it requests the external devices and channel configurations connected to the computing board from the computing board and establishes links with the external devices according to the channel configurations; S3, the communication board collects channel data in real time, generates channel status, and periodically sends the channel status to the computing board; S4, the computing board elects the master channel for each external device according to the channel status and periodically sends master channel election information to the communication board; S5, the communication board obtains the master channel information of all external devices from the computing board periodically, updates it locally, and sends the master channel data from multiple redundant channels to the computing board for processing. This reduces the bandwidth occupancy of the platform's internal bus, increases the overall data access volume of the platform, and improves the processing efficiency of the computing board.

Description

Technical Field

[0001] This invention relates to the field of vehicle safety platform data acquisition technology, and more specifically to a vehicle safety platform data acquisition method based on real-time channel switching. Background Technology

[0002] In rail transit train control systems, ATP (Automotic Train Protection) and ATO (Automatic Train Operation) systems both operate on an onboard safety platform. This platform enables data transmission and processing across various interface types, including relay interfaces, networks, serial ports, and buses. Each application cycle outputs drive commands and status data to different interfaces through the onboard safety platform to drive onboard equipment and facilitate information exchange with preceding and following trains and ground equipment. Simultaneously, the application also receives operational status data from train interface relays and other peripheral communication data collected by the onboard safety platform to ensure safe train operation.

[0003] The vehicle safety platform connects to various types of devices, among which network and serial port devices have the largest communication data volume. Network and serial port devices often use redundant channels for communication, and the same data will be transmitted on multiple channels. The traditional approach is for the vehicle safety platform's communication board to collect data from all network and serial port channels and send all channel data to the computing board for processing via the bus. For data from redundant channels, the computing board only takes one channel of data as valid data for processing, while the data from the other channels is discarded. This approach not only wastes a lot of communication bandwidth of the platform's internal bus, but also increases the processing load of the computing board. Summary of the Invention

[0004] To overcome the shortcomings of the existing technology, this invention discloses a data acquisition method for an in-vehicle safety platform based on real-time channel switching. In this invention, the computing board selects a main channel in real time from multiple redundant channels according to the status of redundant channels uploaded by the communication board. The communication board then sends the main channel data from the multiple redundant channels to the computing board for processing based on the main channel information selected by the computing board. This method not only greatly reduces the bandwidth occupancy of the platform's internal bus and increases the data access volume of the entire platform, but also improves the processing efficiency of the computing board.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A data acquisition method for an onboard safety platform based on real-time channel switching includes the following steps:

[0007] I. Startup of the computing board

[0008] S1. After the computing board starts up, it loads all external devices and channel configurations.

[0009] Preferably, before step S1, the method further includes: numbering all external devices communicating with the vehicle safety platform, with each external device represented by a number Sj (i=1..m); numbering all redundant channels communicating between external device Sj and the vehicle safety platform, with each channel represented by a number Pi (i=1...n), and the external devices and channels are represented as Sj{P1,...,Pn}.

[0010] Preferably, step S1 includes: after the computing board is powered on, loading all external devices and their channel configurations from FLASH, and classifying them according to the external devices and corresponding channels connected to each communication board, without selecting the main channel of each external device during initialization.

[0011] II. Communication Board Startup

[0012] S2. After the communication board starts up, it requests the external devices and channel configurations connected to this board from the computing board, and establishes a link with the external devices according to the channel configuration.

[0013] Preferably, step S2 includes: after the communication board is powered on, it obtains the external devices and corresponding channel configurations that the current board needs to connect to from the computing board via the bus, and establishes a link with the external devices according to the channel configuration.

[0014] III. Channel Status Statistics

[0015] S3. After the channel link is successfully established, the communication board collects channel data in real time to generate channel status and periodically sends the channel status to the computing board.

[0016] Preferably, in step S3, the channel status information sent by the communication board to the computing board is a four-byte integer value V. The generation of the channel status value V includes the following steps:

[0017] S31. After the communication board enters normal operation, it reads the communication data of all channels of the board in real time and determines whether the communication data of the channel is a known protocol type. If so, proceed to step S32; otherwise, proceed to step S33.

[0018] S32. For channel data with a defined protocol and containing a message sequence number, after the communication board reads the channel data, it parses the data according to the protocol format, takes the message sequence number as the status value of the channel, and then proceeds to step S34.

[0019] S33. For channel data with uncertain protocols, the communication board increments the channel status value by one each time it successfully reads the channel data, and then proceeds to step S34.

[0020] S34. Every T cycle, the communication board will package all the channel statuses recorded on this board and send them to the computing board via the bus. At the same time, it will clear the status values ​​of all channels and enter the next channel status generation cycle.

[0021] IV. Main Passage Election

[0022] S4. The computing board selects the master channel for each external device based on the channel status and periodically sends master channel selection information to the communication board.

[0023] Preferably, in step S4, the computing board elects the master channel for each external device based on the received channel status information from all communication boards, and broadcasts the master channel election information to all communication boards. The master channel election includes the following steps:

[0024] S41. After the computing board enters normal operation, it processes the channel status information of all communication boards once every T cycle, sets the status value corresponding to channel Pa of external device Sj to Va, the initial value of Va is 0, and the status of all channels of external device Sj is Sj{V1,...,Vn};

[0025] S42. If the external device Sj has not elected a master channel and the status value Vi (i=1...n) of any channel of the external device Sj is greater than 0, then the computing board starts to independently accumulate the status value of each channel of the external device Sj. The status value of the channel Pa after accumulation is recorded as Ea. After accumulating for two consecutive cycles, if Ea=MAX(E1,...,En), then the channel Pa corresponding to Ea is taken as the master channel of the external device Sj, and Ea is used as the reference value R for calculating the channel status of the external device in subsequent cycles.

[0026] Preferably, in step S42, if Ea = Eb and is greater than the cumulative state value of other channels, then the main channel is elected according to the channel number in ascending order.

[0027] S43. After the main channel of external device Sj is determined to be Pa, starting from the next cycle, other channels use R as a reference value to calculate the channel status value of this channel in the current cycle.

[0028] Preferably, in step S43, calculating the channel state value of this channel in the current period using R as a reference value includes:

[0029] W = R - V1' + V2';

[0030] Where W represents the current channel's calculated status value, R represents the external device reference value, V1' represents the current channel's status value obtained from the communication board, and V2' represents the main channel's status value obtained from the communication board.

[0031] Each channel will use the calculated result W as the reference value R for the calculated state value of that channel in the next cycle.

[0032] S44. If the state value Wb calculated by two consecutive periodic channels Pb is less than 0, and Wb=MIN(W1,...Wn), then the calculation board will switch the main channel of external device Sj to Pb, and at the same time use the absolute value |Wb| as the reference value R of the external device, and continue to repeat the main channel election process of S43.

[0033] Preferably, in step S44, if Wb = Wc and is less than the calculation results of other channels, the main channel is selected according to the channel number in ascending order; where a, b, and c represent the elements in the channel set, namely channel a, channel b, and channel c.

[0034] V. Main Channel Update and Data Transmission

[0035] S5: The communication board obtains the main channel information of all external devices from the computing board every cycle and updates it locally. It also sends the main channel data from the multiple redundant channels to the computing board for processing, while discarding non-main channel data.

[0036] Preferably, step S5 includes: if the channel currently being read by the communication board is not the main channel, the read channel data is discarded directly and not sent to the computing board; otherwise, the main channel data is sent to the computing board in real time via the bus.

[0037] If the communication board does not receive the main channel information sent by the computing board for two consecutive cycles, it will promote all local channels to the main channel.

[0038] The beneficial effects of this invention are:

[0039] This invention provides a statistical method for channel status, which can quickly identify the communication quality of network or serial port channels; it also provides a master channel election method, which can quickly select the channel with better communication quality from multiple redundant channels as the main data acquisition channel. This method of pre-processing redundant channels not only significantly reduces the bandwidth occupancy of the platform's internal bus and increases the overall data access volume of the platform, but also improves the processing efficiency of the computing board. Attached Figure Description

[0040] Figure 1 This is the data communication logic structure of the vehicle-mounted safety platform of the present invention;

[0041] Figure 2 This is the interaction process of the channel status between the computing board and the communication board in this invention;

[0042] Figure 3 This is a detailed flowchart of the communication board channel status statistics of the present invention;

[0043] Figure 4 This is a detailed process for the main channel election of the computing board in this invention;

[0044] Figure 5 This is a detailed process for redundant channel data acquisition in this invention. Detailed Implementation

[0045] The following will provide a clear and complete description of the concept, specific structure, and technical effects of the present invention in conjunction with the embodiments and accompanying drawings, so as to fully understand the purpose, features, and effects of the present invention.

[0046] Example 1

[0047] A data acquisition method for an onboard safety platform based on real-time channel switching includes the following steps:

[0048] 1. Number all external devices that communicate with the platform. Each external device is represented by the number Sj (i=1..m). Number all redundant channels that communicate between external device Sj and the platform. Each channel is represented by the number Pi (i=1...n). Devices and channels can be represented as Sj{P1,...,Pn}.

[0049] 2. After the computing board is powered on, it loads all external devices and their channel configurations from the FLASH memory and categorizes them according to the external devices and corresponding channels connected to each communication board. During initialization, the main channel of each external device is not selected.

[0050] 3. After the communication board is powered on, it obtains the external devices and corresponding channels that the current board needs to connect to from the computing board through the bus, and establishes a link with the external devices according to the channel configuration.

[0051] 4. After the computing board and communication board enter normal operation, the communication board sends the status information of all channels of its own board to the computing board every 50 milliseconds, and the computing board broadcasts the main channel election information of all external devices to all communication boards every 50 milliseconds.

[0052] 5. The channel status information sent from the communication board to the computing board is a four-byte integer value V. The channel status value V is generated in the following way:

[0053] 5.1 After the communication board enters normal operating condition, it reads the communication data of all channels of this board in real time;

[0054] 5.2 For channel data with a defined protocol and containing a message sequence number (such as Subset-037, RSSP-I, etc. protocol data), after the communication board reads the channel data, it parses the data according to the protocol format and takes the message sequence number as the status value of the channel.

[0055] 5.3. For the channel data of an uncertain protocol (such as RAW data), each time the communication board successfully reads the channel data, the channel status value is incremented by one.

[0056] 5.4. Every 50 milliseconds, the communication board packets all the channel statuses recorded on this board and sends them to the calculation board via the bus. At the same time, it clears the status values of all channels and enters the next channel status generation cycle.

[0057] 6. The calculation board elects the main channel of each external device based on all the channel status information of the communication board received and broadcasts the main channel election information to all communication boards. The main channel is elected in the following way:

[0058] 6.1. After the calculation board enters the normal operation state, it processes all the channel status information of the communication board every 50 milliseconds. Assume that the status value corresponding to channel Pa of device Sj is Va (initial value is 0), then all the channel statuses of Sj are Sj{V1,...,Vn};

[0059] 6.2. If device Sj has not elected a main channel yet and the status value Vi (i = 1...n) of any channel of Sj is greater than 0, then the calculation board starts to independently accumulate the status values of each channel of Sj. The accumulated status value of channel Pa is denoted as Ea. After continuously accumulating for two 50 - millisecond cycles, if Ea = MAX(E1,...,En), then the channel Pa corresponding to Ea is taken as the main channel of device Sj, and at the same time, Ea is taken as the reference value R of this device;

[0060] If Ea = Eb and is greater than the status accumulation values of other channels, then the main channel is elected according to the ascending order of the channel numbers, that is, if Pa < Pb, then Pa is elected as the main channel;

[0061] 6.3. After the main channel of device Sj is determined to be Pa, starting from the next cycle, the other channels use R as the reference value and calculate the channel status value of this channel in the current cycle through the following formula:

[0062] W = R - V1’ + V2’;

[0063] Where, W represents the calculated status value of the current channel, R represents the device reference value, V1’ represents the channel status value obtained by the current channel from the communication board, and V2’ represents the channel status value obtained by the main channel from the communication board.

[0064] Each channel takes the calculation result W as the reference value R for calculating the channel status value of this channel in the next cycle.

[0065] 6.4. If the status value Wb calculated for two consecutive cycles of channel Pb is less than 0, and Wb = MIN(W1,...Wn), the calculation board switches the main channel of device Sj to Pb, and at the same time uses the absolute value |Wb| as the reference value R for this device, and continues to repeat the main channel election process in 6.3.

[0066] If Wb = Wc and is less than the calculation results of other channels, the main channel is selected in ascending order of channel numbers, that is, if Pb < Pc, then Pb is elected as the main channel.

[0067] 7. The communication board obtains the main channel information of all devices from the calculation board every cycle and updates it locally. If the currently read channel is not the main channel, the channel data after reading is directly discarded and not sent to the calculation board. Otherwise, the main channel data is sent to the calculation board in real time through the bus.

[0068] 8. If the communication board does not receive the main channel information sent by the calculation board for two consecutive cycles, all local channels are promoted to the main channel.

[0069] Embodiment 2

[0070] This embodiment is further elaborated on the basis of Embodiment 1. Refer to Figure 1 , the peripheral device sends data to the communication board through the redundant channel, and after the communication board collects the data, it sends the peripheral device data to the calculation board through the bus.

[0071] Refer to Figure 2 to introduce the channel status interaction process between the communication board and the calculation board of the present invention, including the following steps:

[0072] Step 100, after the calculation board starts, it loads all peripheral device and channel configurations from the FLASH.

[0073] Step 101, after the communication board starts, it requests the peripheral devices and channel configurations connected to this board from the calculation board.

[0074] Step 102, the communication board establishes a link with the peripheral device according to the configuration.

[0075] Step 103, after the channel link is successfully established, the communication board starts to collect channel data in real time and generate the channel status.

[0076] Step 104, the communication board sends the channel status to the calculation board periodically.

[0077] Step 105, the calculation board elects the main channel of each peripheral device according to the channel status.

[0078] Step 106, the calculation board sends the channel election information to the communication board periodically.

[0079] Refer to Figure 3This invention introduces a channel state generation method, which includes the following steps:

[0080] Step 107: The communication board establishes a channel link with the peripheral device according to the channel configuration;

[0081] Step 108: After the channel link is successfully established, the communication board begins to read the channel data;

[0082] Step 109: If the current channel data is of a known protocol type and contains a message sequence number, the communication board parses the data according to the protocol type and extracts the message sequence number from the data as the current channel status value.

[0083] Step 110: If the current channel data is of unknown type, the communication board increments the channel status value by one for each data packet successfully read.

[0084] Step 111: At the end of every 50-millisecond cycle, the communication board sends the channel status packet to the computing board and clears the channel status generated in this cycle.

[0085] refer to Figure 4 This invention introduces a method for electing the master channel on a computing board, comprising the following steps:

[0086] Step 112: After the computing board enters normal operation, it waits to receive channel status information from all communication boards.

[0087] Step 113: If any channel status value of device Sj is greater than 0, the calculation board starts to independently accumulate all channel values ​​of the device, and the accumulated value is recorded as E.

[0088] Step 114: After accumulating two consecutive cycles, if Ea = MAX(E1,...,En), then Pa is elected as the main channel of device Sj, and Ea is used as the reference value for calculating the channel status in subsequent cycles.

[0089] Step 115: The calculation board continues to receive the channel status sent by the communication board, and calculates the status values ​​of other non-main channels of device Sj every cycle according to the formula W=R-V1'+V2'.

[0090] Step 116: If Wb is less than 0 for two consecutive periods and Wb = MIN(W1,...,Wn), then switch the main channel Pa of Sj to Pb, and use |Wb| as the reference value for calculating the channel state in subsequent periods.

[0091] Step 117: The computing board repeats the process of step 115, switching the main channel in real time.

[0092] refer to Figure 5 This invention introduces a data acquisition and uploading method for a communication board, comprising the following steps:

[0093] Step 118: The communication board receives the main channel information sent by the computing board in real time and updates it locally;

[0094] Step 119: If no main channel information is received for two consecutive cycles, the communication board will promote all channels of this board to the main channel;

[0095] Step 120: The communication board reads the data from all channels of this board in sequence;

[0096] Step 121: If the currently read channel is the primary channel, then package the data and send it to the computing board; otherwise, discard the read data directly.

[0097] The embodiments of the present invention have been described in detail above, but the present invention is not limited to the described embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention, and these equivalents or substitutions are all included within the scope defined by the claims of the present invention.

Claims

1. A vehicle-mounted safety platform data acquisition method based on channel real-time switching, characterized in that, Comprising the following steps: All external devices in communication with the vehicle-mounted safety platform are numbered, each external device being denoted by a number Sj (j = 1..m); all redundant channels in communication with the vehicle-mounted safety platform are numbered, each channel being denoted by a number Pi (i = 1..n), the external device and the channel being denoted as Sj{P1,...,Pn}; S1, after the calculation board is started, all external devices and channel configurations are loaded; S2, after the communication board is started, the calculation board is requested for the external device and channel configuration connected by the board card, and a link is established with the external device according to the channel configuration; S3, after the channel link is successfully established, the communication board collects channel data in real time to generate a channel state, and periodically sends the channel state to the calculation board; S4, the calculation board elects a main channel for each external device according to the channel state, and periodically sends the main channel election information to the communication board, comprising the following steps: S41, after the calculation board enters a normal operating state, the channel state information of all communication boards is processed once every T period, the state value corresponding to the channel Pa of the external device Sj is set as Va, the initial value of Va is 0, and the channel state of the external device Sj is Sj{V1,...,Vn}; S42, if the external device Sj does not currently elect a main channel, and any channel state value Vi (i = 1..n) of the external device Sj is greater than 0, the calculation board starts to independently accumulate the channel state value of each channel of the external device Sj, the accumulated state value of the channel Pa is denoted as Ea, and after two consecutive periods of accumulation, if Ea = MAX(E1,...,En), the channel Pa corresponding to Ea is taken as the main channel of the external device Sj, and Ea is taken as the reference value R for the subsequent period calculation of the channel state of the external device; S43, after the main channel of the external device Sj is determined as Pa, from the next period, the other channels take R as the reference value to calculate the channel state value of the current period, comprising: W = R-V1’+V2’; Wherein, W represents the state value calculated by the current channel, R represents the reference value of the external device, V1’ represents the channel state value obtained by the current channel from the communication board, and V2’ represents the channel state value obtained by the main channel from the communication board; Each channel takes the calculation result W as the reference value R for the calculation of the channel state value in the next period; S44, if the state value Wb calculated by the channel Pb is less than 0 for two consecutive periods, and Wb = MIN(W1,...Wn), the calculation board switches the main channel of the external device Sj to Pb, and takes the absolute value |Wb| as the reference value R of the external device, and continues to repeat the main channel election process of S43; S5, the communication board obtains the main channel information of all external devices from the calculation board every period and updates it to the local, and sends the main channel data in the multi-redundant channel to the calculation board for processing, and discards the non-main channel data.

2. The in-vehicle safety platform data collection method of claim 1, wherein, The S1 step comprises: after the calculation board is powered on, all external devices and channel configurations are loaded from the FLASH, and are classified according to the external devices connected by each communication board and the corresponding channels, and the main channel of each external device is not selected during initialization.

3. The in-vehicle security platform data collection method of claim 1, wherein, S2 step includes: after the communication board is powered on, the current card needs to be connected to the external device and the corresponding channel configuration is obtained from the computing board through the bus, and the link with the external device is established according to the channel configuration.

4. The in-vehicle safety platform data collection method of claim 1, wherein, In S3 step, the channel state information sent by the communication board to the computing board is a four-byte integer value V, and the generation of the channel state value V includes the following steps: S31, after the communication board enters the normal running state, the communication data of all channels of the board card is read in real time, and it is judged whether the communication data of the channel is a known protocol type, if yes, step S32 is entered, if not, step S33 is entered; S32, for the channel data of the determined protocol and containing the message sequence number, the communication board reads the channel data, parses the data according to the protocol format, and cancels the message sequence number as the state value of the channel, and then enters step S34; S33, for the channel data of the uncertain protocol, the communication board adds one to the channel state value every time the channel data is successfully read once, and then enters step S34; S34, the communication board packages all the channel states recorded by the board card every T period, and sends them to the computing board through the bus, and clears all the channel state values, and enters the next channel state generation period.

5. The in-vehicle safety platform data collection method of claim 1, wherein, In S42 step, if Ea=Eb and greater than the state accumulation value of other channels, the master channel is selected according to the order of channel number from small to large.

6. The in-vehicle safety platform data collection method of claim 1, wherein, In S44 step, if Wb=Wc and less than the calculation result of other channels, the master channel is selected according to the order of channel number from small to large; Wherein, a, b, c represent elements in the channel set, that is, a channel, b channel and c channel.

7. The in-vehicle security platform data collection method of claim 1, wherein, S5 step includes: if the channel currently read by the communication board is not the master channel, the channel data after reading is directly discarded and not sent to the computing board, otherwise the master channel data is sent to the computing board in real time through the bus; If the communication board does not receive the master channel information sent by the computing board for two consecutive periods, all local channels are upgraded to master channels.

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