Data acquisition and real-time control system based on EtherCAT bus

Abstract

The present invention relates to the field of precision measurement and control technology, specifically to a data acquisition and real-time control system based on an EtherCAT bus, comprising a device under test, a data acquisition system and a control system connected in sequence, wherein the data acquisition system and the control system are connected via an EtherCAT bus. The present invention uses the EtherCAT bus as a communication interface between the data acquisition system and the control system, can achieve seamless connection and data sharing between the data acquisition system and the control system, uses the stable communication mechanism and error detection function of the EtherCAT bus, enhances the stability and reliability of the system; and can design an intuitive and easy-to-use user interface and operation process based on this, and optimizes the user's operating experience.

Description

Technical Field

[0001] The invention belongs to the technical field of precision measurement and control, and specifically relates to a data acquisition and real-time control system based on an EtherCAT bus. Background Art

[0002] Traditionally, data acquisition systems (DAQ) and real-time control systems (PLC) are two independent parts. Data acquisition systems focus on collecting various physical quantity information at high speed and high precision, while real-time control systems focus on quickly responding to control needs and adjusting or controlling industrial processes. Data exchange between the two often requires middleware or complex interfaces, which leads to complex systems, high costs, and data transmission delays, affecting control accuracy and efficiency. In addition, systems in the prior art often have limitations in terms of environmental adaptability, signal synchronization, and scalability.

[0003] When trying to merge data acquisition with real-time control systems, the first challenge is the complexity of system integration. The traditional independent system architecture leads to a large number of interfaces, protocols and hardware compatibility issues that need to be dealt with during the integration process. This not only increases the difficulty of technical implementation, but may also lead to system performance degradation and reliability issues.

[0004] Real-time data transmission is a key challenge when merging DAQ with real-time control systems. Since data acquisition and real-time control have extremely high time sensitivity requirements, any delay in data transmission may lead to degraded control performance or system instability. In addition, as the amount of data increases, how to ensure efficient and accurate data transmission has also become a problem that needs to be solved.

[0005] When merging DAQ with real-time control systems, compatibility and interoperability between different systems is an important consideration. Different manufacturers may use different communication protocols, data formats, and interface standards, which increases the difficulty of system integration. In addition, as technology continues to develop, how to ensure that the system is compatible with new devices and standards is also a problem that needs to be considered.

[0006] In practical applications, data acquisition and real-time control systems often need to face various complex environmental conditions. However, existing systems often have difficulty working stably in extreme environments (such as high temperature, high humidity, high vibration, etc.). This may lead to problems such as system performance degradation, data loss or equipment damage, affecting the reliability and stability of the system.

[0007] With the advancement of technology and the continuous changes in application requirements, the system needs to be able to flexibly expand and upgrade to support new devices and functions. However, existing merged systems often face difficulties in scalability and upgrade maintenance. This includes the limitations of hardware expansion, the inconvenience of software upgrades, and the complexity of system maintenance. These problems may cause the system to be unable to meet the growing needs and increase the cost of long-term maintenance.

[0008] Security and reliability are two crucial aspects in the process of merging DAQ with real-time control systems. Since the system may involve the transmission of sensitive data and the execution of critical control tasks, any security loopholes or failures may lead to serious consequences. Therefore, how to ensure the security and reliability of the system has become an urgent issue to be solved. This includes considerations such as data encryption, access control, backup and recovery mechanisms, etc.

[0009] The merged system often has richer functions and more complex operation processes. However, this may also cause the user interface and operation to become complicated and difficult to use. For non-professional users, it may be a challenge to understand and operate such a system. Therefore, how to design an intuitive and easy-to-use user interface and operation process has become an issue that needs to be considered.

[0010] As the complexity and functionality of the merged system increase, more training and support are needed for users to master and use such a system. This includes technical training, operation guidance, troubleshooting and other support. However, the existing training and support resources may not be able to meet the growing demand, resulting in difficulties for users during use.

[0011] The present invention provides a system that integrates data acquisition and real-time control functions, which is particularly suitable for improving the efficiency and accuracy of industrial automation, automotive testing, aerospace and other precision measurement and control fields. Specifically, the present invention combines the technologies of high-speed data acquisition system and real-time control system, aiming to provide a unified platform that can not only efficiently collect and process large amounts of data, but also make control decisions in real time based on these data, thereby optimizing system performance and reducing equipment cost and maintenance complexity. Summary of the invention

[0012] In view of the deficiencies in the prior art, the present invention provides a data acquisition and real-time control system based on EtherCAT bus to solve the above technical problems.

[0013] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a data acquisition and real-time control system based on EtherCAT bus, comprising a device under test, a data acquisition system and a real-time control system connected in sequence, wherein the data acquisition system and the control system are connected via the EtherCAT bus.

[0014] Furthermore, the EtherCAT bus network includes 1 master station and 4 slave stations connected to the master station in sequence.

[0015] Furthermore, after the master station initializes the network and broadcasts configuration information to all slave stations, each slave station configures itself according to the received configuration information and prepares to communicate with the master station; during the communication process, the master station sends data frames to the EtherCAT bus, and when each slave station receives these data frames, it adds its own timestamp to the frame to record the time when the data arrives and is processed; then, these data frames with timestamps will continue to be transmitted along the bus to the next slave station node until all slave stations are processed and finally return to the master station; in the process of returning to the master station, the data frame retains the timestamp of each slave station, so that the master station can calculate the processing delay of each slave station.

[0016] Furthermore, the master station periodically sends data frames to all slave stations.

[0017] Furthermore, the configuration information includes a unique identifier, a network location, and an allocated I / O register address of each slave station.

[0018] Furthermore, when the master station sends data frames, it also sends a global time reference to all slave stations. The slave stations use this time reference to calibrate their internal clocks to achieve time synchronization for the entire network. After configuration is complete, the slave stations send confirmation messages to the master station, indicating that they have been configured and synchronized to the time reference of the master station. After receiving confirmation from all slave stations, the master station confirms that the entire network has been initialized and is ready for communication.

[0019] Furthermore, the data acquisition system has a built-in analog-to-digital converter.

[0020] Compared with the prior art, the data acquisition and real-time control system based on EtherCAT bus of the present invention has the following beneficial effects:

[0021] The present invention adopts EtherCAT bus as the communication interface between PLC and DAQ system, which can realize seamless connection and data sharing between PLC and DAQ system, and adopts the stable communication mechanism and error detection function of EtherCAT bus to enhance the stability and reliability of the system; and can design an intuitive and easy-to-use user interface and operation process based on it, and optimize the user's operation experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is the traditional way to connect DAQ and PLC.

[0023] Figure 2This is a connection method between the data acquisition system and the control system based on the EtherCAT bus of the present invention.

[0024] Figure 3 The working principle and topological structure of the EtherCAT network of the present invention are shown.

[0025] Among them, 1. Device under test; 2. DAQ; 3. PLC; 4. Analog output interface of DAQ; 5. Analog input interface of PLC; 6. EtherCAT bus; 7. Master station; 8. Slave station. DETAILED DESCRIPTION

[0026] 1. Traditional DAQ and PLC connection method

[0027] In traditional systems, DAQ2 and PLC3 communicate through a large number of hard-wired connections.

[0028] like Figure 1 As shown, the device under test 1 usually includes a sensor or a switch, which is a device for monitoring physical parameters or control signals; DAQ2 is a device for collecting sensor signals and performing preliminary processing; PLC3 is a device for receiving data from DAQ2 and performing logical control; the analog output interface 4 of DAQ is an interface for outputting analog control signals to PLC3; the analog input interface 5 of PLC is an interface for receiving analog signals from DAQ2.

[0029] This method not only has complex wiring and high cost, but also increases the difficulty of system maintenance, so it has low flexibility.

[0030] The present invention has made the following improvements on the basis of the prior art.

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] like Figure 2 The figure shows a schematic diagram of a data acquisition and real-time control system based on the EtherCAT bus of the present invention.

[0033] The device under test 1 , DAQ2 , and PLC3 are connected in sequence, wherein DAQ2 and PLC3 are connected via an EtherCAT bus 6 .

[0034] The device under test 1 refers to a sensor or a switch, which is a device used to detect physical parameters or control signals.

[0035] DAQ2 is a device that collects signals from the device under test 1 and performs preliminary processing. It integrates EtherCAT communication capabilities and has an EtherCAT interface.

[0036] PLC3 is a device that receives data from DAQ2 and performs logic control. It also has an EtherCAT interface.

[0037] The EtherCAT bus 6, which serves as a data transmission channel between DAQ2 and PLC3, has the advantages of high efficiency and low latency.

[0038] After the introduction of EtherCAT bus 6, a high degree of integration between DAQ2 and PLC3 is achieved, and only one EtherCAT bus 6 is needed to complete the high-speed bidirectional transmission of all data. This fusion architecture not only reduces hardware costs, but also simplifies system wiring, while significantly improving the overall response speed and flexibility of the system. In the specific signal processing and transmission process, DAQ2 first collects analog signals from the device under test 1, and then converts the analog signals into digital signals through its built-in analog-to-digital converter (ADC). These digital signals are then packaged into Ethernet frames and sent through EtherCAT bus 6. Due to the efficient data transmission capability of EtherCAT bus 6, these data can quickly reach PLC3. On the PLC3 side, the data frames received by the EtherCAT master from EtherCAT bus 6 are unpacked, the timestamp and measurement data are extracted, and the preset control logic is executed based on these data.

[0039] The working principle and topology of the EtherCAT network in the EtherCAT bus 6 are as follows: Figure 3 As shown, in a specific embodiment, the EtherCAT network consists of 1 master station and 4 slave stations. After the master station initializes the network and broadcasts configuration information to all slave stations, each slave station performs self-configuration according to the received configuration information and prepares to communicate with the master station. During the communication process, the master station sends data frames to the EtherCAT bus. When each slave station receives these data frames, it will add its own timestamp in the frame to record the time when the data arrives and is processed. Subsequently, these data frames with timestamps will continue to be transmitted along the bus to the next slave station node until all slave stations are processed and finally return to the master station. In this way, the master station can use these timestamps to calculate the processing delay of each slave station node and ensure the synchronization of the entire system. For example, on an automated production line, the master station may need to synchronously control multiple sensors and actuators. Each slave station node adds a timestamp when receiving the data frame, ensuring the order and time accuracy of the data, thereby achieving accurate monitoring and control. In other embodiments, the configuration of the slave station can select other quantities, subject to the actual scenario needs.

[0040] In the EtherCAT network, the time determinism and synchronization of the system are achieved by the master periodically sending a global synchronization signal or timestamp to all slaves. After receiving the synchronization signal, each slave will record the reception time locally and add its own timestamp when processing the data. This timestamp reflects the specific moment when the slave receives the synchronization signal and processes the data. In the process of returning the data frame to the master, the timestamp of each slave is retained, so that the master can calculate the processing delay of each slave. By comparing the timestamp returned by the slave with the timestamp sent, the master can determine the response time and processing time of each slave, and adjust the communication cycle accordingly to ensure the synchronization of the entire system. In this process, the time determinism and synchronization of each slave node can be guaranteed.

[0041] When the system is initialized, the master station first performs a self-check and prepares the network configuration information, and then broadcasts this configuration information to all slave stations through the network, including parameters such as the unique identifier of each slave station, the network location, and the assigned I / O register address. After receiving the broadcast, each slave station configures itself according to the provided configuration information, sets network parameters, initializes I / O registers, and prepares to communicate with the master station. At the same time, the master station sends a global time base to all slave stations, and the slave stations use this time base to calibrate their internal clocks to achieve time synchronization for the entire network. After the configuration is complete, the slave stations send a confirmation message to the master station, indicating that they have been configured and synchronized to the master station's time base. After receiving the confirmation from all slave stations, the master station confirms that the entire network has been initialized and is ready for communication. Through this fusion method, the components of the system can work more closely together, improving the performance and efficiency of the entire industrial automation solution.

[0042] In the present invention, the connection method between the data acquisition system and the control system based on the EtherCAT bus has the following advantages:

[0043] First, it has efficient real-time data transmission.

[0044] The use of EtherCAT bus technology significantly improves the speed and real-time performance of data transmission. Compared with traditional technologies, EtherCAT bus provides faster data transmission rate and lower latency, ensuring real-time data exchange between data acquisition and control systems, thereby improving the response speed and efficiency of the entire system.

[0045] Second, simplified system integration and scalability.

[0046] The PLC and DAQ system are seamlessly connected through the EtherCAT bus, simplifying the system integration process. At the same time, the modular design of the EtherCAT bus allows the system to be flexibly expanded and configured as needed to meet the needs of different application scenarios, improving the flexibility and scalability of the system.

[0047] Third, enhanced system compatibility and interoperability.

[0048] The EtherCAT bus supports a variety of communication protocols and data formats, making it possible to easily integrate devices and sensors from different manufacturers. This enhanced compatibility and interoperability reduces the difficulty of system integration and improves the compatibility and stability of the system.

[0049] Fourth, optimized user interface and operating experience.

[0050] By optimizing the user's operation process, the user's learning cost is reduced, the user's operation efficiency and satisfaction are improved. Users can easily control and manage the system.

[0051] Fifth, improved system stability and reliability.

[0052] The EtherCAT bus ensures the accuracy of data transmission and the stability of system operation through its stable communication mechanism and error detection functions, such as cyclic redundancy check (CRC) and frame check sequence (FCS). Specifically, the redundant communication configuration allows the system to automatically switch to the backup link when a link fails to ensure uninterrupted communication. The fast retransmission mechanism quickly triggers the retransmission of data when the data frame is detected to be lost or damaged, reducing the impact of data loss on system stability. In addition, the present invention also uses the Advanced Encryption Standard (AES) to encrypt data to protect the data from unauthorized access or tampering during transmission, and implements a strict access control policy to ensure that only authorized users and devices can access system resources. These measures jointly improve the security of system data, reduce security risks, and ensure the high reliability and stability of the system.

[0053] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0054] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. Data acquisition and real-time control system based on EtherCAT bus, characterized by: The invention comprises a tested device, a data acquisition system and a real-time control system which are connected in sequence, and the data acquisition system and the control system are connected via an EtherCAT bus.

2. The data acquisition and real-time control system based on EtherCAT bus as claimed in claim 1, characterized in that: The network of the EtherCAT bus includes one master station and four slave stations connected to the master station in sequence.

3. The data acquisition and real-time control system based on EtherCAT bus as claimed in claim 2, characterized in that: When the master station initializes the network and broadcasts configuration information to all slave stations, each slave station configures itself according to the received configuration information and prepares to communicate with the master station; During the communication process, the master sends data frames to the EtherCAT bus. When each slave receives these data frames, it adds its own timestamp to the frame to record the time when the data arrived and was processed; These data frames with timestamps will then continue to be transmitted along the bus to the next slave node until all slave nodes have processed them and finally return to the master node; In the process of returning the data frame to the master station, the timestamp of each slave station is retained, so that the master station can calculate the processing delay of each slave station.

4. The data acquisition and real-time control system based on EtherCAT bus as claimed in claim 3, characterized in that: The master station periodically sends data frames to all slave stations.

5. The data acquisition and real-time control system based on EtherCAT bus as claimed in claim 3, characterized in that: The configuration information includes a unique identifier, a network location, and an assigned I / O register address for each of the slaves.

6. The data acquisition and real-time control system based on EtherCAT bus as claimed in claim 3, characterized in that: When the master sends a data frame, it also sends a global time reference to all slaves. The slaves use this time reference to calibrate their internal clocks to achieve time synchronization for the entire network. After configuration is complete, the slaves send confirmation messages to the master, indicating that they have been configured and synchronized to the master's time base. After the master receives confirmation from all slaves, it confirms that the entire network has been initialized and is ready for communication.

7. The data acquisition and real-time control system based on EtherCAT bus as claimed in claim 1, characterized in that: The data acquisition system has a built-in analog-to-digital converter.

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