Communication conversion system for connecting field bus master station and servo press controller

Abstract

The invention discloses a communication conversion system for connecting a field bus master station and a servo press controller, and belongs to the field of electronic data processing. According to the module, an STM32F103CT6 is adopted as a main control CPU (Central Processing Unit), a three-network-port framework is formed in cooperation with a W5500 Ethernet chip and an Anybus B40 multi-protocol communication chip, and seamless switching of the EtherCAT protocol, the EtherNet / IP protocol and the Profinet protocol can be realized through firmware programming. Triple technical schemes are innovatively provided: 1) a three-state sensing network based on pressure, motion and fault signals realizes dynamic priority scheduling (response delay is less than or equal to 10 microseconds); 2) adopting IEEE 1588v2 hardware clock synchronization (the precision is less than or equal to 100ns) and adaptive Kalman filtering to reduce a multi-axis cooperative control position error to 0.02 mm; and 3) designing an exponential backoff retransmission (the retransmission interval is 200 [mu] s + / -50 [mu] s) and a three-level verification fault-tolerant mechanism, so that the bit error rate is reduced to 10 <-6 >.

Description

Technical Field

[0001] This invention belongs to the field of electronic data processing, specifically a communication conversion system that connects a fieldbus master station and a servo press controller. Background Technology

[0002] The current communication architecture of industrial fieldbus and servo press control systems suffers from significant technical bottlenecks: traditional solutions using a single protocol conversion module result in poor system scalability, and protocol switching requires hardware modifications, averaging 2-3 hours; existing priority scheduling mechanisms employ a static allocation mode, leading to command response delays of 50-100ms under emergency conditions such as pressure exceeding limits (>50MPa), failing to meet the 10ms response requirement for safety control commands in ISO 13849-1; clock synchronization relies on software time synchronization (NTP protocol), with synchronization errors exceeding 1ms, resulting in position deviations exceeding 0.15mm during multi-axis collaborative control; data verification relies solely on a single CRC algorithm, and fault recovery requires manual intervention, severely disrupting normal equipment operation. Furthermore, existing modules generally suffer from insufficient temperature adaptability and excessively high bus load rates leading to a sharp drop in throughput, severely hindering the intelligent upgrading of manufacturing equipment.

[0003] To address the problems in the background art, this application designs a communication conversion system that connects a fieldbus master station and a servo press controller. Summary of the Invention

[0004] To address the problems in the background art, this invention proposes a communication conversion system that connects a fieldbus master station and a servo press controller.

[0005] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, the present invention provides a communication conversion system connecting a fieldbus master station and a servo press controller, comprising the following specific modules:

[0006] Servo press control unit: responsible for receiving instructions from the central processing unit, controlling the operation of the servo press, and collecting the performance data of the servo press;

[0007] Network interface module: Used to receive data from the servo press control unit and forward it to the central processing unit;

[0008] Central processing unit: It processes the data sent by the servo press control unit and sends the converted data to the fieldbus communication module according to the processing results; at the same time, it is also responsible for transmitting the instructions sent by the PLC main control unit to the servo press control unit.

[0009] Communication module: Used to transmit data processed by the central processing unit to the PLC main control unit;

[0010] PLC main control equipment: used to receive data transmitted by the communication module and generate PLC control instructions accordingly;

[0011] Fieldbus communication module: responsible for managing data communication on the fieldbus, including data reception and transmission;

[0012] Secondly, the present invention provides a communication conversion system for connecting a fieldbus master station and a servo press controller, wherein the communication conversion transmission includes the following specific steps:

[0013] S11. Initialize the two SPI interfaces;

[0014] S12. Initialize the network chip to ModbusTCP client mode, read the server IP address stored in EEPROM, connect to the server, proceed to S13 if the connection is successful, and return to S11 if the connection fails.

[0015] S13. Connection successful. Send a command to the ModbusTCP server at a frequency of 1Hz to read the number of slave stations.

[0016] S14, ModbusTCP server reply, where the last byte indicates the number of slave stations;

[0017] S15. The CPU initializes the data area length of the AnybusB40 module based on the number of slave stations read earlier. One slave station corresponds to 48 bytes, two slave stations correspond to 96 bytes, and so on.

[0018] S16. Entering the data interaction stage, the CPU sends a 0x10 write command to the ModbusTCP server at 100ms intervals, writing the data received by the AnybusB40 module.

[0019] S17. Wait for the MlodbusTCP server to respond to the 0x10 command. If the wait times out, proceed to S12; otherwise, proceed to S18.

[0020] S18. Upon receiving the reply to the 0x10 command, send the 0x03 read command to the ModbusTCP server;

[0021] S19. Wait for the ModbusTCP server to respond to the 0x03 command. If the wait times out, proceed to S12. If the wait does not time out, proceed to S20.

[0022] S20: Upon receiving the reply to command 0x03, the received data is placed into the transmit buffer of AnyBusB40.

[0023] Thirdly, the present invention provides a communication conversion system for connecting a fieldbus master station and a servo press controller, wherein the communication sequence includes the following specific steps:

[0024] S31. Based on the real-time working status parameters of the servo press, including pressure threshold, motion stage or fault signal, dynamically calculate the priority level of the communication message.

[0025] S32. A hybrid algorithm combining time-slice polling and preemptive scheduling is adopted to respond to high-priority messages immediately and allocate transmission resources to ordinary messages according to preset time slices.

[0026] S33. Parse the original message of the fieldbus master station, extract the service identifier (SID) and process data, and encapsulate them into a standardized data unit that can be recognized by the servo press controller.

[0027] S34. Align the clock signals of the master station and the compressor controller through a hardware-level clock synchronization protocol, and use a filtering algorithm to compensate for transmission delay;

[0028] S35. For messages that do not respond within a timeout period, initiate an exponential backoff retransmission strategy and automatically discard messages that fail verification.

[0029] The priority level of communication messages is dynamically calculated based on the real-time operating status parameters of the servo press, including pressure threshold, motion stage, or fault signal.

[0030] S311. Real-time acquisition of the status parameters of the servo press, including pressure sensor data, encoder signals during motion, and fault diagnosis signals;

[0031] S312. Based on the status parameters, dynamically calculate the message priority level according to preset rules, wherein:

[0032] Emergency priority triggering conditions: When sensor data exceeds the preset safety threshold and lasts for more than 10ms, it will automatically be upgraded to the highest emergency priority and trigger the master station interruption response mechanism.

[0033] High-priority triggering conditions: If the device is in a high-speed movement phase (speed ≥ 1m / s) or is performing high-precision positioning, a high priority will be assigned to ensure the real-time performance of motion control commands.

[0034] Default priority rule: For parameter configuration commands or non-real-time status query commands, assign a default priority and allow bulk transfers when the bus load is below 70%;

[0035] The priority level is embedded in the header field of the communication message for the bus scheduling module to call;

[0036] S313. The fault signal includes overcurrent, overheating or mechanical jamming, which triggers the highest emergency priority and interrupts the transmission of all current normal messages.

[0037] The hybrid algorithm, which combines time-slice round-robin and preemptive scheduling, provides immediate responses to high-priority packets and allocates transmission resources to ordinary packets according to preset time slices.

[0038] S321. The reference time slice for the time slice polling is dynamically adjusted based on the bus load rate, and the calculation formula is as follows:

[0039]

[0040] S322, The triggering conditions for the preemptive scheduling are: the waiting time of a high-priority message exceeds its maximum allowed delay; the bus idle time percentage is less than 10%;

[0041] S323. The hybrid algorithm is hardware accelerated in FPGA, and the scheduling decision delay is ≤10μs.

[0042] The original messages from the parsed fieldbus master station are extracted, the Service Identifier (SID) and process data are extracted, and encapsulated into standardized data units that can be recognized by the servo press controller.

[0043] S331. The standardized data unit adopts the CANopen object dictionary format and includes: timestamp (4 bytes, precision 1μs); priority identifier (1 byte, 0x00-0x02 corresponds to Level 0-Level 2); process data (maximum 8 bytes);

[0044] S332. The parsing of the Service Identifier (SID) includes: extracting the DPV1 service code from the PROFIBUS message; and extracting the CoE (CANopen over EtherCAT) index from the EtherCAT message.

[0045] S333. The encapsulated data unit must pass CRC-16 verification. If the verification fails, the fault handling process of claim S313 will be triggered.

[0046] The clock signals between the master station and the compressor controller are aligned using a hardware-level clock synchronization protocol, and a filtering algorithm is used to compensate for transmission delay.

[0047] S341. The hardware-level clock synchronization protocol is the IEEE 1588v2 Precision Time Protocol (PTP), with a synchronization accuracy ≤100ns. The master station and the press controller use a transparent clock mode for timestamp correction. The clock synchronization process includes: the master station recording timestamp t1 when sending a Sync message; the press controller receiving the message, recording timestamp t2, and returning a Delay_Req message containing t1 and t2; and the master station calculating the clock offset.

[0048]

[0049] Where t3 is the compressor sending time, and t4 is the master station receiving time;

[0050] S343. The filtering algorithm is an adaptive Kalman filter, and its parameter dynamic adjustment process includes:

[0051] State equation: x k =Ax k-1 +w k % (A is the state transition matrix, w k (for process noise);

[0052] Observation equation: z k =Hx k +v k (H is the observation matrix, v) k To measure noise, the process noise covariance Q = σ is updated in real time based on the standard deviation σ of historical delay data. 2 When a sudden delay is detected, the system automatically switches to sliding window mean filtering, with a window size W = 5-10 sampling periods. For packets that do not respond within a timeout period, an exponential backoff retransmission strategy is initiated, and packets that fail verification are automatically discarded.

[0053] S351, the retransmission interval of the exponential backoff retransmission strategy is calculated according to the following formula:

[0054] T retry =T base ×2 n-1 +R rand

[0055] Where T base The base interval is (200μs ± 50μs), n is the current retransmission count (1 ≤ n ≤ 5), and R rand The random jitter is within the range of [-20%, +20%]; when the number of retransmissions reaches the maximum threshold (n=5): trigger a bus error interrupt, mark the corresponding compressor as "offline", stop scheduling its messages, and push a device fault alarm through the HMI interface;

[0056] S352, the determination of the verification failure message includes: CRC check mismatch (polynomial 0x1021); data length field does not match the actual number of bytes received; priority identifier exceeds the preset range (>0x02); when the verification failure message is discarded, the following are executed simultaneously: record the error type and occurrence time to non-volatile memory (EEPROM); update the bus error counter (counted once every 1ms cycle); when the continuous error count >10 times, automatically reduce the communication rate of the press by 50%; for emergency messages discarded due to verification failure, additional triggers are made: immediately send a hardware reset pulse to the press; send redundant control commands through the backup RS-485 channel.

[0057] Fourthly, the present invention provides a CPU model STM32F103CT6, a network chip model W5500, and a communication module model AnybusB40.

[0058] Compared with existing technologies, the beneficial effects of this application are as follows: First, the triple state perception network based on pressure sensors, motion encoders, and fault diagnosis units, combined with an FPGA-accelerated hybrid scheduling algorithm, improves command response speed by 52.3%, achieving a decision latency of 10μs in parallel testing of 8 devices. Second, the innovative CANopen object dictionary encapsulation format supports PROFIBUS / EtherCAT dual protocol conversion, and combined with CRC-16 checksum and exponential backoff retransmission strategy, reduces the bit error rate from 10... -4 Reduced to 10 -6 The data throughput reached 48Mbps. Finally, by employing IEEE 1588v2 hardware synchronization technology and an adaptive Kalman filter algorithm, the motion control position error was reduced from 0.15mm to 0.02mm. Attached Figure Description

[0059] Figure 1 A schematic diagram illustrating the internal working principle of a communication conversion system.

[0060] Figure 2 A schematic diagram of the communication conversion and data transmission processing flow. Specific Implementation

[0061] The purpose of this invention is to provide a communication conversion system that connects a fieldbus master station and a servo press controller.

[0062] In a first aspect, the present invention provides a communication conversion system for connecting a fieldbus master station and a servo press controller, comprising the following steps:

[0063] The servo press controller is used to execute instructions from the central processing unit to achieve precise motion control of the servo press and to collect status data of the pressing process in real time.

[0064] An Ethernet controller is used to receive data from the servo press controller and transmit it to the central processing unit via a bus protocol.

[0065] Servo press control unit: responsible for receiving instructions from the central processing unit, controlling the operation of the servo press, and collecting the performance data of the servo press;

[0066] Network interface module: Used to receive data from the servo press control unit and forward it to the central processing unit;

[0067] Central processing unit: It processes the data sent by the servo press control unit and sends the converted data to the fieldbus communication module according to the processing results; at the same time, it is also responsible for transmitting the instructions sent by the PLC main control unit to the servo press control unit.

[0068] Communication module: Used to transmit data processed by the central processing unit to the PLC main control unit;

[0069] PLC main control equipment: used to receive data transmitted by the communication module and generate PLC control instructions accordingly;

[0070] Fieldbus communication module: This module is responsible for managing data communication on the fieldbus, including data reception and transmission.

[0071] Secondly, the present invention provides a communication conversion system for connecting a fieldbus master station and a servo press controller, wherein the communication conversion transmission includes the following specific steps:

[0072] S11. Initialize the two SPI interfaces;

[0073] S12. Initialize the network chip to IodbusTCP client mode, read the server IP address stored in EEPROM, connect to the server, proceed to S13 if the connection is successful, and return to S11 if the connection fails.

[0074] S13. Connection successful. Send a command to the ModbusTCP server at a frequency of 1Hz to read the number of slave stations.

[0075] S14, ModbusTCP server reply, where the last byte indicates the number of slave stations;

[0076] S15. The CPU initializes the data area length of the AnybusB40 module based on the number of slave stations read earlier. One slave station corresponds to 48 bytes, two slave stations correspond to 96 bytes, and so on.

[0077] S16. Entering the data interaction stage, the CPU sends a 0x10 write command to the ModbusTCP server at 100ms intervals, writing the data received by the AnybusB40 module.

[0078] S17. Wait for the MlodbusTCP server to respond to the 0x10 command. If the wait times out, proceed to S12; otherwise, proceed to S18.

[0079] S18. Upon receiving the reply to the 0x10 command, send the 0x03 read command to the ModbusTCP server;

[0080] S19. Wait for the ModbusTCP server to respond to the 0x03 command. If the wait times out, proceed to S12. If the wait does not time out, proceed to S20.

[0081] S20: Upon receiving the reply to command 0x03, the received data is placed into the transmit buffer of AnyBusB40.

[0082] Thirdly, the present invention provides a communication conversion system for connecting a fieldbus master station and a servo press controller, wherein the communication sequence includes the following specific steps:

[0083] S31. Based on the real-time working status parameters of the servo press, including pressure threshold, motion stage or fault signal, dynamically calculate the priority level of the communication message.

[0084] S32. A hybrid algorithm combining time-slice polling and preemptive scheduling is adopted to respond to high-priority messages immediately and allocate transmission resources to ordinary messages according to preset time slices.

[0085] S33. Parse the original message of the fieldbus master station, extract the service identifier (SID) and process data, and encapsulate them into a standardized data unit that can be recognized by the servo press controller.

[0086] S34. Align the clock signals of the master station and the compressor controller through a hardware-level clock synchronization protocol, and use a filtering algorithm to compensate for transmission delay;

[0087] S35. For messages that do not respond within a timeout period, initiate an exponential backoff retransmission strategy and automatically discard messages that fail verification.

[0088] The priority level of communication messages is dynamically calculated based on the real-time operating status parameters of the servo press, including pressure threshold, motion stage, or fault signal.

[0089] S311. Real-time acquisition of the status parameters of the servo press, including pressure sensor data, encoder signals during motion, and fault diagnosis signals;

[0090] It should be specifically noted that: the pressure sensor monitors the over-limit pressure in real time; the multi-turn encoder decodes speed / displacement data at 1MHz to dynamically determine the motion stage; the temperature / vibration / current modules form a fault diagnosis system; the data is transmitted via EtherCAT and synchronized with the IEEE1588v2 clock to realize state machine control and fault tree analysis on the STM32H743 chip.

[0091] S312. Based on the status parameters, dynamically calculate the message priority level according to preset rules, wherein:

[0092] Emergency priority triggering conditions: When sensor data exceeds the preset safety threshold and lasts for more than 10ms, it will automatically be upgraded to the highest emergency priority and trigger the master station interruption response mechanism.

[0093] High-priority triggering conditions: If the device is in a high-speed movement phase (speed ≥ 1m / s) or is performing high-precision positioning, a high priority will be assigned to ensure the real-time performance of motion control commands.

[0094] Default priority rules: For parameter configuration commands or non-real-time status query commands, a default priority is assigned, and batch transmission is allowed when the bus load is below 70%; the priority level is embedded in the header field of the communication message for the bus scheduling module to call.

[0095] S313. The fault signal includes overcurrent, overheating or mechanical jamming, which triggers the highest emergency priority and interrupts the transmission of all current normal messages.

[0096] It should be specifically noted that the system first acquires key parameters in real time through a high-precision sensor network: a piezoresistive pressure sensor monitors pressure data at a sampling frequency of 1kHz, and immediately triggers a hardware interrupt signal when the detected pressure exceeds the safety threshold for 10ms; a 23-bit multi-turn absolute encoder calculates motion speed and displacement in real time at a decoding frequency of 1MHz, and dynamically determines whether the device is in an acceleration, constant speed, or deceleration phase through a preset algorithm; simultaneously, a triple fault diagnosis system consisting of a PT100 temperature sensor, a MEMS vibration sensor, and a Hall current module monitors abnormal states such as overcurrent, overheating, and mechanical jamming in real time. All sensor data is transmitted to the STM32H743 main control chip via an EtherCAT bus, and clock synchronization of ≤100ns is achieved based on the IEEE1588v2 protocol. The main control chip operates a state machine control algorithm, dynamically allocating message priorities based on real-time parameters: Pressure exceeding limits or fault signals trigger Level 0 emergency priority, immediately interrupting normal messages and sending a PROFIsafe safety command; Level 1 high priority is assigned during high-speed movement or high-precision positioning; normal operation is set to Level 2 default priority, with batch transmission mode enabled when bus load is <70%. Priority tags are embedded in a CANopen object dictionary format message via a 3-byte header field and transmitted after CRC-16 verification.

[0097] The hybrid algorithm, which combines time-slice round-robin and preemptive scheduling, provides immediate responses to high-priority packets and allocates transmission resources to ordinary packets according to preset time slices.

[0098] S321. The reference time slice for the time slice polling is dynamically adjusted based on the bus load rate, and the calculation formula is as follows:

[0099]

[0100] S322, The triggering conditions for the preemptive scheduling are: the waiting time of a high-priority message exceeds its maximum allowed delay; the bus idle time percentage is less than 10%;

[0101] S323. The hybrid algorithm is hardware accelerated in FPGA, and the scheduling decision delay is ≤10μs.

[0102] It should be specifically noted that: First, the dynamic time slice management module collects bus utilization in real time through the load monitoring unit built into the Xilinx Artix-7 FPGA, based on the formula... The time slice length is dynamically adjusted, with the load rate L_current obtained through the MAC layer frame counter. Secondly, the preemption arbiter continuously monitors two types of events: high-priority packets waiting for longer than their corresponding maximum latency threshold or bus idle time < 10%. Preemption is triggered when either condition is met, at which point the FPGA immediately suspends the currently transmitting ordinary packets and the DMA controller directly transmits the high-priority packets to the PHY interface. Finally, all scheduling decisions are completed in the FPGA hardware logic, using a pipelined state machine design. Actual measurements show that the end-to-end latency from event triggering to scheduling execution is stable at 8.2 ± 1.3 μs.

[0103] The original messages from the parsed fieldbus master station are extracted, the Service Identifier (SID) and process data are extracted, and encapsulated into standardized data units that can be recognized by the servo press controller.

[0104] S331. The standardized data unit adopts the CANopen object dictionary format and includes: timestamp (4 bytes, precision 1μs); priority identifier (1 byte, 0x00-0x02 corresponds to Level 0-Level 2); process data (maximum 8 bytes);

[0105] S332. The parsing of the Service Identifier (SID) includes: extracting the DPV1 service code from the PROFIBUS message; and extracting the CoE (CANopen over EtherCAT) index from the EtherCAT message.

[0106] S333. The encapsulated data unit must pass CRC-16 verification. If the verification fails, the fault handling process of claim S313 will be triggered.

[0107] Specifically, the following points need to be explained: First, the protocol parsing layer uses a hardware acceleration module to disassemble the original message in real time. For PRO FIBUSDP-V1 messages, deep packet inspection technology is used to extract the DPV1 service code. For EtherCAT frames, the CoE mailbox protocol parsing object dictionary index is used, and the index number is stored in the data field 0x1C-0x1F. Second, the data reconstruction engine encapsulates the extracted SID and process data (≤8 bytes) in the CANopen object dictionary format, inserts a 4-byte high-precision timestamp and a 1-byte priority tag at the header, and appends a 2-byte CRC-16 checksum at the tail, with a polynomial of 0x1021 and a hardware CRC unit calculation delay of ≤0.8μs. Finally, the verification module compares the received CRC with the calculated value. If it fails, the fault handling procedure S313 is immediately triggered, including discarding the message, updating the EEPROM error log, and degrading the communication rate.

[0108] The clock signals between the master station and the compressor controller are aligned using a hardware-level clock synchronization protocol, and a filtering algorithm is used to compensate for transmission delay.

[0109] S341. The hardware-level clock synchronization protocol is the IEEE 1588v2 Precision Time Protocol (PTP), with a synchronization accuracy ≤100ns. The master station and the press controller use a transparent clock mode for timestamp correction. The clock synchronization process includes: the master station recording timestamp t1 when sending a Sync message; the press controller receiving the message, recording timestamp t2, and returning a Delay_Req message containing t1 and t2; and the master station calculating the clock offset. Where t3 is the compressor sending time and t4 is the master station receiving time.

[0110] S342. The filtering algorithm is an adaptive Kalman filter, and its dynamic parameter adjustment process includes:

[0111] State equation: x k =Ax k-1 +w k % (A is the state transition matrix, w k (for process noise);

[0112] Observation equation: z k =Hx k +v k (H is the observation matrix, v) k (For measuring noise);

[0113] Based on the standard deviation σ of historical delay data, the process noise covariance Q = σ is updated in real time. 2 When a sudden delay is detected, it automatically switches to sliding window mean filtering, with a window size W of 5 to 10 sampling periods.

[0114] It should be noted that: Firstly, the system uses the IEEE 1588v2 PTP protocol to achieve hardware-level clock synchronization between the master station and the compressor controller. This is achieved through a four-step timestamp exchange in transparent clock mode, with Sync and Delay_Req message interactions, combined with the 10ns precision timestamp unit of the Xilinx Zynq FPGA, resulting in a synchronization accuracy of 82±15ns. To compensate for network latency, the system integrates an adaptive Kalman filter algorithm, whose state equation and observation equation parameters are dynamically adjusted based on the historical delay standard deviation (Q=σ). 2 When a burst delay of >500μs is detected, it automatically switches to 8-cycle sliding window mean filtering.

[0115] The exponential backoff retransmission strategy is initiated for messages that do not respond within a timeout period, and messages that fail verification are automatically discarded:

[0116] S351, the retransmission interval of the exponential backoff retransmission strategy is calculated according to the following formula:

[0117] T retry =T base ×2 n-1 +R rand

[0118] Where T base The base interval is (200μs ± 50μs), n is the current retransmission count (1 ≤ n ≤ 5), and R rand The random jitter is within the range of [-20%, +20%]; when the number of retransmissions reaches the maximum threshold (n=5): trigger a bus error interrupt, mark the corresponding compressor as "offline", stop scheduling its messages, and push a device fault alarm through the HMI interface;

[0119] S352, the determination of the verification failure message includes: CRC check mismatch (polynomial 0x1021); data length field does not match the actual number of bytes received; priority identifier exceeds the preset range (>0x02); when the verification failure message is discarded, the following are executed simultaneously: record the error type and occurrence time to non-volatile memory (EEPROM); update the bus error counter (counted once every 1ms cycle); when the continuous error count >10 times, automatically reduce the communication rate of the press by 50%; for emergency messages discarded due to verification failure, additional triggers are made: immediately send a hardware reset pulse to the press; send redundant control commands through the backup RS-485 channel.

[0120] It should be specifically noted that: timeout messages are handled through a dynamic exponential backoff algorithm, and after 5 failed retransmissions, the device is offline isolated and the HMI is set to a level 3 alarm; at the same time, a triple verification system is configured to perform graded handling of abnormal messages - ordinary errors are recorded to EEPROM and their frequency is counted, while emergency message errors are triggered by a hardware reset pulse and RS-485 redundant channel switching.

[0121] Fourthly, this invention provides the core hardware architecture of the communication conversion system: the main control unit uses ST's STM32F103CT6 as the central processing unit, responsible for protocol conversion and scheduling control; the network communication layer is configured with Wiznet's W5500 Ethernet chip (providing one RJ45 interface) to realize Modbus TCP basic communication; the fieldbus interface uses AnybusB40 multi-protocol chip (with two RJ45 interfaces), its innovation lies in the fact that by burning different firmware, it can seamlessly switch to support three mainstream industrial protocols: EtherCAT, EtherNet / IP and Profinet, and each protocol version maintains full hardware pin compatibility.

Claims

1. A communication conversion system for connecting a field bus master station to a servo press controller, characterized by, The specific modules include: a servo press control unit for receiving instructions from a central processing device, controlling the operation of the servo press, and collecting performance data of the servo press; a network interface module for receiving data from the servo press control unit and forwarding to the central processor; a central processing device for processing data sent by the servo press control unit and sending converted data to the field bus communication module according to the processing result; at the same time, it is also responsible for transmitting the instructions from the PLC host device to the servo press control unit; a communication module for transmitting data processed by the central processing device to the PLC host device; a PLC host device for receiving data transmitted by the communication module and generating PLC control instructions accordingly; a field bus communication module for managing data communication on the field bus, including data reception and transmission.

2. A communication conversion system for connecting a field bus master station to a servo press controller according to claim 1, wherein The communication conversion transmission includes the following specific steps: S11, initializing two SPI interfaces; S12, initializing the network chip as a ModbusTCP client mode, reading the server IP address stored in the EEPROM, connecting the server, and performing S13 if the connection is successful, or returning to S11 if the connection fails; S13, if the connection is successful, send a command to read the number of slave stations to the ModbusTCP server at a frequency of 1Hz; S14, the ModbusTCP server replies, and the last byte indicates the number of slave stations; S15, the CPU initializes the data area length of the AnybusB40 module according to the number of slave stations read in the previous step, one slave station corresponds to 48 bytes, two slave stations correspond to 96 bytes, and so on; S16, enter the data interaction stage, the CPU sends 0x10 write command to the ModbusTCP server at a time interval of 100ms, and the content of the write command is the data received by the AnybusB40 module; S17, wait for the reply of the ModbusTCP server to the 0x10 command, if the waiting time is exceeded, perform S12, if the waiting time is not exceeded, perform S18; S18, receive the reply to the 0x10 command, and send 0x03 read command to the ModbusTCP server; S19, wait for the reply of the ModbusTCP server to the 0x03 command, if the waiting time is exceeded, perform S12, if the waiting time is not exceeded, perform S20; S20, receive the reply to the 0x03 command, and put the received data into the send buffer of the AnyBusB40.

3. A communication conversion system for connecting a field bus master station to a servo press controller as defined in claim 2, wherein, The communication sorting includes the following specific contents: S31, dynamically calculate the priority level of the communication message according to the real-time working state parameters of the servo press, including pressure threshold, motion stage or fault signal; S32, use a hybrid algorithm combining time slice polling and preemptive scheduling to respond to high-priority messages immediately and allocate transmission resources to ordinary messages according to the preset time slice; S33, analyze the original message of the field bus master station, extract the service identifier (SID) and process data, and encapsulate them as standardized data units recognizable by the servo press controller; S34, aligning the clock signals of the host station and the press controller through a hardware-level clock synchronization protocol, and compensating for transmission delay using a filtering algorithm; S35, starting an exponential backoff retransmission strategy for messages that do not respond within a timeout, and automatically discarding messages that fail verification.

4. A communication conversion system for connecting a field bus master station to a servo press controller according to claim 3, wherein, According to real-time working state parameters of the servo press, including pressure threshold, motion stage, or fault signal, the priority level of the communication message is dynamically calculated: S311, real-time acquisition of state parameters of the servo press, including pressure sensor data, motion stage encoder signal, and fault diagnosis signal; S312, according to the state parameters, dynamically calculating the priority level of the message according to the preset rule, wherein: Emergency priority trigger condition: when the sensor data exceeds the preset safety threshold and lasts more than 10ms, it is automatically upgraded to the highest emergency priority, and the host station interrupt response mechanism is triggered; High priority trigger condition: the device is in high-speed motion stage (speed ≥ 1m / s) or is performing high-precision positioning, then high priority is assigned to ensure the real-time performance of motion control instructions; Default priority rule: for parameter configuration instructions or non-real-time state query instructions, assign a default priority, and allow batch transmission when the bus load is less than 70%; Embed the priority level in the header field of the communication message for the bus scheduling module to call; S313, the fault signal includes overcurrent, overheating, or mechanical jamming, triggering the highest emergency priority and interrupting all current ordinary message transmission.

5. A communication conversion system for connecting a field bus master station to a servo press controller as defined in claim 3, wherein, A hybrid algorithm combining time slice polling and preemptive scheduling is used to respond to high-priority messages immediately and allocate transmission resources to ordinary messages according to the preset time slice: S321, the reference time slice of the time slice polling is dynamically adjusted according to the bus load rate, and the calculation formula is: S322, the trigger condition of the preemptive scheduling is that the waiting time of the high-priority message exceeds its maximum allowed delay, and the bus idle time ratio is less than 10%; S323, the hybrid algorithm is implemented in FPGA for hardware acceleration, and the scheduling decision delay is ≤10μs.

6. A communication conversion system for connecting a field bus master station to a servo press controller as defined in claim 3, wherein, Parse the original message of the field bus host station, extract the service identifier (SID) and process data, and package them into a standardized data unit recognizable by the servo press controller: S331, the standardized data unit uses the CANopen object dictionary format, which includes: timestamp (4 bytes, precision 1μs); priority identifier (1 byte, 0x00-0x02 corresponds to Level 0-Level 2); process data (maximum 8 bytes); S332, the service identifier (SID) analysis includes: extracting the DPV1 service code in the PROFIBUS message; extracting the CoE (CANopen over EtherCAT) index in the EtherCAT message; S333, the packaged data unit needs to pass CRC-16 verification, and when the verification fails, the fault handling process of claim S313 is triggered.

7. A communication conversion system for connecting a field bus master station to a servo press controller as defined in claim 3, wherein, Align the clock signals of the host station and the press controller through a hardware-level clock synchronization protocol, and compensate for transmission delay using a filtering algorithm: S341、the hardware-level clock synchronization protocol is IEEE 1588v2 Precision Time Protocol (PTP), the synchronization accuracy is ≤100 ns, and a transparent clock (Transparent Clock) mode is adopted between the master station and the press controller for timestamp correction; wherein the clock synchronization process comprises: recording a timestamp t1 when the master station sends a Sync message; recording a timestamp t2 after receiving the message by the press controller, and returning a Delay_Req message with t1 and t2; and calculating a clock offset by the master station: Wherein t3 is the sending time of the press, and t4 is the receiving time of the master station; S342、the filtering algorithm is an adaptive Kalman filter, and the parameter dynamic adjustment process comprises: State equation: x k = Ax k-1 + w k (A is state transition matrix, w k is process noise); Observation equation: z k = Hx k + v k (H is observation matrix, v k is measurement noise), according to the standard deviation σ of historical delay data, real-time update process noise covariance Q = σ 2 , when detecting sudden delay, automatically switch to sliding window mean filter, window size W = 5-10 sampling periods.

8. A communication conversion system for connecting a field bus master station to a servo press controller as defined in claim 3, wherein, an exponential backoff retransmission strategy is started for the message that is not responded in time, and the message that fails in the check is discarded automatically: S351、the retransmission interval time of the exponential backoff retransmission strategy is calculated according to the following formula: T retry = T base x 2 n-1 + R rand where T base is the base interval (200 μs ± 50 μs), n is the current retransmission number (1 ≤ n ≤ 5), R rand is a random jitter in the range [-20%, +20%]; when the retransmission number reaches the maximum threshold (n = 5): a bus error interrupt is triggered, the corresponding press is marked as "offline state", its packets are stopped from being scheduled, and a device fault alarm is pushed through the HMI interface; S352、the judgment of the message that fails in the check comprises: CRC check mismatch; the data length field does not match the actual received byte number; the priority identifier exceeds the preset range; and the discarded message that fails in the check is synchronized to record the error type and the occurrence time to the nonvolatile memory (EEPROM); the bus error counter is updated, and the error count is counted once every 1 ms period; when the continuous error count is greater than 10 times, the communication speed of the press is reduced by 50% automatically; for the emergency message discarded due to the check failure, an additional trigger is performed: a hardware reset pulse is immediately sent to the press; and a redundant control instruction is sent through a backup RS-485 channel.

9. A communication conversion system for connecting a field bus master station to a servo press controller as defined in claim 2, wherein, The CPU model is STM32F103CT6, the network chip model is W5500, and the communication module model is Anybus B40.

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