Combined dynamic and static testing machine controller

Abstract

The invention discloses a combined dynamic and static testing machine controller, which comprises at least one controller, and the controller can be independently used and is matched with a computer to form a control system of various single-shaft or double-shaft testing machines. A plurality of controllers can be combined by using a special communication protocol and are matched with a computer to serve as a control system of various multi-axis testing machines. The combined type dynamic and static testing machine controller provided by the invention has the following technical effects: by setting a distributed topological combination mode, the controllers can be free from communication, and when one controller and corresponding equipment go wrong, the controller and the corresponding equipment can be independently replaced without influencing other equipment; by setting a centralized topological combination mode, special communication exists between the controllers, when the requirement of a control system exceeds the computing power of one controller, a special computing power controller can be used for executing a computing function, and the method can be conveniently applied to high-precision multi-axis tight coupling linkage single equipment.

Description

Technical Field

[0001] The invention belongs to the technical field of testing machine controllers, and in particular relates to a combined dynamic and static testing machine controller. Background Art

[0002] In a broad sense, a testing machine is an instrument that verifies the quality or performance of a product or material according to design requirements before it is put into use. From the definition, it can be seen that any instrument that verifies quality or performance can be called a testing machine.

[0003] Common static mechanical testing and mechanical simulation equipment include universal material testing machine (electronic or hydraulic), torsion and bending testing machine, rock press, rock direct shear tester, rock triaxial tester, etc. Common dynamic mechanical testing equipment include impact testing machine, fatigue testing machine, vibration testing machine.

[0004] In many scientific research and special fields, there are also non-standard static and dynamic mechanical testing machines specially designed for non-standard needs, such as construction, geotechnical engineering, pile foundation, and dynamic and static mechanical research and development and testing equipment for various new parts.

[0005] In addition to standard and non-standard, static and dynamic, testing machines can also have numbers of axes ranging from single axis to dozens of axes.

[0006] Some test machine controllers are required to be installed inside the test machine or on the panel; some test machine controllers are required to be made into desktop control boxes; some test machine controllers are required to be made into separate floor-standing control cabinets.

[0007] Therefore, there are many types of testing machines, and the controllers used to control the corresponding testing machines, as well as the control systems composed of controllers and software, are also varied. The control system of high-performance mechanical testing equipment is more complicated than that of multi-axis CNC machine tools. The latter only requires multi-axis motion linkage control to execute path walking, while the former also requires precise force displacement deformation multiple sensor acquisition and real-time closed-loop control of different modes. High-performance non-standard mechanics is a top scientific research equipment with high technical indicators. The requirements for measurement and control accuracy and speed will reach the industry's limit. However, the higher the performance of the testing machine, the fewer the number of machines required, especially high-end scientific research equipment, which often only has one.

[0008] At present, the controllers of mainstream mechanical equipment can be roughly divided into two categories, general-purpose and special-purpose. Relatively speaking, general-purpose controllers are mainly controlled by PLC. Relying on the high adaptability, reliability and easy operation of PLC, general-purpose controllers can be compatible with various types of equipment. However, its performance is relatively worse, and the resolution of the most core analog signals such as force and displacement of mechanical equipment is low. At the same time, the communication rate is low and the delay is high, which makes it unsuitable for the high-precision and high-performance environment of real-time communication. Although the special-purpose controller can adapt well to non-standard and high-precision mechanical equipment and has excellent processing performance, in order to meet the above powerful performance, it often takes a lot of financial resources and time for research and development and debugging; and because of its strong specialization, the control system is usually only applicable to one corresponding testing machine, and when the testing machine changes, it needs to be remade.

[0009] Based on the above description, the following questions are summarized: Problem 1: Due to its inherent defects, the current PLC controller cannot be used in scenarios with high accuracy and performance requirements; Question 2: Dedicated controllers are difficult and costly to produce, and have a long development cycle. To ensure high performance and reliability, a lot of time, energy, and material resources are required.

[0010] Question 3: The number of non-standard testing machines is small and the index requirements are high, resulting in a low return on investment in the development of dedicated controllers adapted for them.

[0011] Question 4: The testing machines have very different requirements for the installation and appearance of the controller, which makes it impossible to unify the controller hardware. Summary of the invention

[0012] In view of this, the present invention provides a combined dynamic and static testing machine controller, which is convenient for use in high-precision single-axis or multi-axis tightly coupled testing machine control, has strong versatility, short development cycle, simple debugging, and flexible installation and appearance.

[0013] The present invention proposes a combined dynamic and static testing machine controller, the controller cooperates with a computer as a control system of the testing machine, and the control system includes at least one controller. In particular, the controller can be used alone, and cooperate with a computer as a control system for a uniaxial and biaxial testing machine; multiple controllers can also be combined using a communication protocol to form a multi-controller system, and cooperate with a computer as a control system for multi-axis and complex testing machines.

[0014] Further improvements: The combination method among multiple controllers is a distributed topology; In the distributed topology method, each controller is at the same level, and each controller works independently to complete its own measurement, calculation, control, and host communication.

[0015] Further improvements: The combination method among multiple controllers is a centralized topology; In the centralized topology method, one of the at least two controllers serves as a core machine and communicates with the computer, and the other controllers are logically regarded as the IO part of the controller serving as the core.

[0016] Further improvements: Multiple controllers are connected via a static collaborative bus; The protocol of the static cooperative bus is divided into four layers, including transport layer, data packet layer, content layer, and physical layer; the physical layer is standard 485.

[0017] The static cooperative communication among multiple controllers adopts single bus 485, and the cooperative 485 communication ports of all controllers are connected to the same 485 bus.

[0018] Further improvements: Each controller is connected through a dynamic collaborative bus; The controller of the core machine serves as a computing power controller and communicates with the computer; other controllers are terminal controllers; the collaborative communication interface of the controller serving as a computing power controller includes 1 485 interface and 8 422 interfaces, and the collaborative communication interface of the controller serving as a terminal controller is a 422 communication interface.

[0019] Further improvements: The controller includes a CPU part, an IO part and a communication part.

[0020] Further improvements: The CPU part includes a static control unit; Used as a high-speed static control unit; Used as a dynamic control unit; Used as a computing power control unit.

[0021] Further improvements: The communication part includes a host communication interface for communicating with the upper-level computer host, a collaborative communication interface for communicating between peers, and a slave communication interface for communicating with supporting lower-level devices; the host communication interface includes three interface modes: USB interface, Ethernet interface and standard serial port.

[0022] Further improvements: The communication protocol of the collaborative bus is divided into 4 layers: transport layer, data packet layer, content layer, and physical layer. Each controller needs to set the collaborative communication parameters in advance, including the local sequence number, the total number of controllers, and the baud rate. The static collaborative communication mode is as follows: Command forwarding mode: The core machine initiates a transmission by sending a command forwarding packet, and the forwarding target controller sends a command reply packet to end the transmission; In this mode, the transmission speed has nothing to do with the measurement and control frequency, but only with the transmission and reception between the computer and the target controller; during this period, all controllers monitor the bus, and irrelevant controllers remain silent; Data transmission mode: The core controller initiates a transmission by sending a start data packet. All controllers take turns sending data packets on the bus according to the token transfer. The core controller sends an end data packet to end the transmission. Each controller monitors the bus, receives and updates the data content it needs. If no content needs to be sent, a data packet with only a header and a tail is sent to pass the token. In this mode, the collaborative bus transmits an equal amount of data per second according to the measurement and control frequency. For example, when the measurement and control frequency is 40 Hz, the collaborative bus transmits 40 times per second. Since each transmission starts from the core controller with serial number 1, the transmission rate is strictly equal to the measurement and control frequency of the core controller. When no external unified analog sampling clock is used, the measurement and control frequencies of each controller have slight deviations. All controllers determine their own sampling time / sampling serial number based on the core controller. Packet sending mechanism of data transmission mode: Packet sending uses a token mechanism, that is, each controller can send data on the bus only after the token is valid. The token starts from the core controller, is passed in sequence according to the sequence number, and finally returns to the core controller again; The core controller is responsible for the start of the transmission, that is, sending the start data packet, which contains at least the sampling number / sampling time, and all controllers update the sampling beat (sequence number / time) accordingly; After all controllers have finished sending packets, the core machine sends an end data packet; Transport layer token passing rules for static cooperative communication between controllers: Each controller has a unique serial number N; Dynamic collaborative communication methods are as follows: Command forwarding mode: The core machine initiates a transmission, and the target controller sends a command reply packet to end the transmission; In this mode, the transmission speed has nothing to do with the measurement and control frequency, but is only related to the transmission and reception of the computer and the target controller; during this period, only the 422 bus of the corresponding controller has transmission, and the 422 bus of the irrelevant controller has no transmission.

[0023] Data transmission mode: The core controller initiates a transmission by sending a start data packet, other controllers send intermediate data packets, and the core controller sends an end data packet to end the transmission; during this period, each 422 bus transmits independently in parallel without affecting each other; In this mode, the transmission speed is strictly consistent with the core machine's measurement and control frequency; Dynamic collaborative packet sending mechanism: Each transmission has three fixed data packets, including the core controller sending the start data packet, other controllers sending the middle data packets, and the core controller sending the end data packet; Error detection and retransmission mechanism: After a controller sends a packet, if other controllers receive it with an error, the bus is immediately pulled down and maintained for 2 bytes of communication time before restoring the bus, and the current controller resends the packet.

[0024] The technical effects of a combined dynamic and static testing machine controller provided by the present invention are as follows: By setting a distributed topology combination mode, the controllers can communicate without being connected and coordinated. At the same time, when a controller and its corresponding line have problems, they can be replaced separately without affecting other devices. By setting up a centralized topology combination, when the control system demand exceeds the computing power of one controller, a dedicated computing power controller is used to perform the calculation function, thereby improving the overall computing power of the system and facilitating its application to a single device with high-precision multi-axis tightly coupled linkage.

[0025] The computing power controller only has computing and communication parts, which are at the core position, and other terminals do not need to be connected to the computer.

[0026] The present invention can also be applied to scenarios with high precision requirements and has good performance. The modular combinable control system has a short development cycle and low cost. It is easy to use and simple to debug. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the centralized topology of the static collaborative bus; Figure 2 It is a schematic diagram of the static collaborative bus distribution topology; Figure 3 It is a schematic diagram of the centralized topology of the dynamic collaborative bus; Figure 4 It is a connection diagram of the controller in the static cooperative bus centralized topology mode; Figure 5 It is a communication diagram of two dynamic controllers in centralized topology mode; Figure 6 It is a communication diagram of three static controllers in centralized topology mode; Figure 7 It is a connection diagram of the controller in the dynamic collaborative bus centralized topology mode; Figure 8 It is the content of the command forwarding packet in command forwarding mode; Fig. 9 It is the content of the command reply packet in command forwarding mode; Fig.10The content of the start packet in data transmission mode; Fig.11 The content of the intermediate packet in data transmission mode; Fig.12 It is the content of the end packet in data transmission mode. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0029] Embodiment 1, as Figure 1 , Figure 4 , Figure 6 As shown, a combined dynamic and static testing machine controller includes at least two controllers, which are connected by a static cooperative bus and a centralized topology, and communicate with each other through a communication protocol. This topology is suitable for static equipment with tightly coupled axes.

[0030] Among at least two controllers, one controller is set as the core machine and communicates with the computer, and the other controllers are logically the IO part of the core machine.

[0031] like Figure 4 As shown in the figure, the static cooperative communication between multiple controllers uses a single bus 485, and the cooperative 485 communication ports of all controllers are connected to the same 485 bus. Each controller has a cooperative communication plug with two signal lines 485+ / 485-. The same signal lines of all controllers are connected in parallel to complete the bus connection. The cooperative 485 interface of each controller uses SN65HVD75 driver and 3.3V power supply. It works at a rate of 2-5Mbps.

[0032] Simplex, single bus, suitable for static controller combinations with small data volume, slow acquisition and control speed. The static collaborative bus supports up to 50 controllers, 100 static linkage axes, and a closed-loop speed of 100Hz.

[0033] Each controller includes a CPU part, an IO part and a communication part.

[0034] The above-mentioned CPU part also includes four types: STM32F103 used as a static controller, STM32F405 used as a high-speed static controller, STM32F767 used as a dynamic controller, and STM32H743 used as a computing power controller.

[0035] The communication part includes a host communication interface for communicating with the upper-level computer host, a collaborative communication interface for communicating between peers, and a slave communication interface for communicating with supporting lower-level devices; among them, the host communication interface includes three interface methods: USB interface, Ethernet interface and standard serial port.

[0036] The IO part includes: analog input signal, analog output signal, digital input signal, digital output signal, switch input signal and switch output signal.

[0037] The analog input signals include millivolt strain gauge signals, ±10V voltage signals and 0-24mA current signals; the analog output signals include ±10V voltage signals and 0-24mA current signals; the digital input signals include single / double pulse encoder signals and SSI protocol signals; the digital output signals include single / double pulse servo motor control signals and PWM signals.

[0038] The special IO section also includes an external input clock signal for unifying the ADC clock signals of different controllers.

[0039] When the computing power of a terminal controller is exceeded, a dedicated computing power controller is used to perform computing functions. The computing power controller only has computing and communication parts and is in the core position. Other terminals do not need to be connected to the computer. The computer only needs to be connected to the core controller and connected to other controllers through command forwarding. The computer is connected to the non-core controller to configure and adjust the configuration parameters of the non-core controller. This only happens when the device is debugged. When the device is working, the computer cannot be directly connected to the non-core controller. The core controller collects the data collected by other controllers and sends the signals that need to be output to other controllers.

[0040] The communication protocol of the static collaborative bus is divided into four layers: transport layer, data packet layer, content layer, and physical layer; each controller needs to set the collaborative communication parameters in advance, including the local sequence number, the total number of controllers, and the baud rate.

[0041] Command forwarding mode under static collaborative communication mode: the core machine sends a command forwarding packet to initiate a transmission, and the forwarding target controller sends a command reply packet to end the transmission.

[0042] In this mode, the transmission speed has nothing to do with the measurement and control frequency, but is only related to the transmission and reception of the computer and the destination controller; during this period, all controllers monitor the bus, and irrelevant controllers remain silent.

[0043] Data transmission mode under static cooperative communication mode: the core controller initiates a transmission by sending a start data packet, and all controllers take turns to send data packets on the bus according to token passing. The core controller sends an end data packet to end this transmission. Each controller monitors the bus, receives and updates the data content it needs; if it does not need to send content, it must send a data packet with only a header and a tail to pass the token.

[0044] In this mode, the collaborative bus transmits an equal amount of data per second according to the measurement and control frequency. For example, when the measurement and control frequency is 40Hz, the collaborative bus transmits 40 times per second; since each transmission starts from the core controller with sequence number 1, the transmission rate is strictly equal to the measurement and control frequency of the core controller. When no external unified analog sampling clock is used, the measurement and control frequencies of each controller have slight deviations, and all controllers determine their own sampling time / sampling sequence number based on the core controller.

[0045] Packet sending mechanism of data transmission mode under static cooperative communication mode: Packet sending uses a token mechanism, that is, each controller can send data on the bus only after the token is valid. The token starts from the core controller, is passed in sequence according to the sequence number, and finally returns to the core controller again.

[0046] The core controller is responsible for the start of the transmission, that is, sending the start data packet, which contains at least the sampling number / sampling time, and all controllers update the sampling beat (sequence number / time) accordingly; After all controllers have finished sending packets, the core machine sends an end data packet; Transport layer token passing rules for static collaborative communication between controllers: Each controller has a unique serial number N.

[0047] Error detection and retransmission mechanism: After a controller sends a packet, if other controllers receive it with an error, the bus is immediately pulled down and maintained for 2 bytes of communication time before restoring the bus, and the current controller resends the packet.

[0048] The controller operates according to the following rules: Rule 1: After the controller sends a data packet, if the bus remains idle for >10us, the token becomes invalid and the next controller token becomes valid.

[0049] Rule 2: After the controller sends a data packet, if the bus is pulled down for more than 11 bits within 5us, the controller token is still valid and the data packet is resent.

[0050] Rule 3: When a controller retransmits twice, the token becomes invalid and the token of the next controller becomes valid. When a controller determines that its reception is wrong three times in a row, it will no longer send a retransmission signal for this transmission (to avoid bus deadlock caused by poor reception of one controller).

[0051] Rule 4: After the last controller token expires, the core controller token becomes valid.

[0052] The data packets of static collaborative communication, each data packet includes a packet header, content (can be empty), and a packet trailer.

[0053] The packet header has a start code, a controller sequence number, and a packet length. The contents may be 0 to several, and each content has two parts: a number and a value. The packet tail is a CRC value (CRC32).

[0054] The packet length value unit is 4 bytes, and the maximum value is 128, that is, the maximum packet length is 512 bytes.

[0055] In the content layer of static collaborative communication, each data packet may or may not have content. The content is divided into a 4-byte index and a 4-byte data.

[0056] The positioning of all controller coordinated communication contents is achieved through a 4-byte index, and the four-byte index is: controller number, content type, content number, and reserved byte.

[0057] The data uses 4 bytes and can be fixed-point or floating-point numbers. Both parties can parse it by index. When the data exceeds 4 bytes, multiple indexes are used to transmit multiple contents.

[0058] Embodiment 2, as Figure 2 As shown, a combined dynamic and static testing machine controller includes at least two controllers. Different from Example 1, the controllers are connected in a distributed topology using a static collaborative bus, and the controllers communicate with each other through a communication protocol. This topology is suitable for static equipment with loose coupling or no coupling between axes.

[0059] In a distributed topology, multiple controllers are at the same level, and each controller works independently to complete its own measurement, calculation, control, and host communication.

[0060] Distributed topology is suitable for applications with low coordination between axes and high reliability requirements, such as multiple independent devices working for a long time. The controllers independently complete their own measurement, calculation, control, and host communication, and can be disconnected for coordinated communication. When a device has a problem, it can be replaced separately without affecting other devices.

[0061] Embodiment 3, as Figure 3 , Figure 5 , Figure 7 As shown, a combined dynamic and static testing machine controller includes at least two controllers. Different from embodiments 1 and 2, the controllers are connected in a centralized topology using a dynamic collaborative bus, and the controllers communicate through a communication protocol.

[0062] In a centralized topology, one controller acts as the core machine and communicates with the computer, and other controllers are logically the IO part of the core machine.

[0063] This topology is suitable for a single dynamic device with multiple axes tightly coupled.

[0064] When the computing power of a terminal controller is exceeded, a dedicated computing power controller is used to perform the computing function. The computing power controller only has the computing and communication parts, which are at the core. Other terminals do not need to be connected to the computer.

[0065] The controller collaborative communication interface of the computing power controller includes 1 485 interface and 8 422 interfaces. The controller collaborative communication interface of the terminal controller is a 422 communication interface.

[0066] The collaborative 422 communication ports of all terminal controllers are connected to different 422 ports of the computing power controller. The duplex independent bus is suitable for dynamic controller combinations with large data volume, fast acquisition and control speed.

[0067] Dynamic coordination is multiple groups of 422 buses, full-duplex, 10Mbps, the computing power controller has 8 422 interfaces, and the terminal dynamic controller has 1 422 interface. One computing power controller supports up to 8 terminal controllers, 10 dynamic linkage axes, and a closed-loop speed of 10KHz.

[0068] The communication protocol of the dynamic collaborative bus is also divided into four layers: transport layer, data packet layer, content layer, and physical layer; each controller also needs to set the collaborative communication parameters in advance, including the local sequence number, the total number of controllers, and the baud rate.

[0069] Command forwarding mode under dynamic collaborative communication mode: the core machine initiates a transmission, and the forwarding target controller sends a command reply packet to end the transmission.

[0070] In this mode, the transmission speed has nothing to do with the measurement and control frequency, but is only related to the transmission and reception of the computer and the target controller; during this period, only the corresponding 422 bus has transmission, and the 422 bus of the irrelevant controller has no transmission.

[0071] Data transmission mode under dynamic collaborative communication mode: the core controller initiates a transmission by sending a start data packet, other controllers send intermediate data packets, and the core controller sends an end data packet to end the transmission; during this period, each 422 bus transmits independently in parallel without affecting each other.

[0072] In this mode, the transmission speed is strictly consistent with the core machine's measurement and control frequency.

[0073] Packet sending mechanism of data transmission mode under dynamic cooperative communication mode: Each transmission has three fixed data packets, namely, the core controller sends a start data packet, other controllers send intermediate data packets, and the core controller sends an end data packet.

[0074] In the dynamic collaborative communication mode, the controller data transmission rules are the same as those in the static collaborative communication mode; the data packets and content layers in the dynamic collaborative communication mode are the same as those in the static collaborative communication.

[0075] Embodiment 4, a combined dynamic and static testing machine controller, is different from the above embodiments in that it only includes one controller, which is directly connected to a computer terminal and cooperates with the computer terminal as a control system of a single-axis or double-axis testing machine to perform computational control on the testing machine.

[0076] Regardless of whether it is a non-standard or general-purpose device, when the IO channels do not exceed those listed above and the number of axes does not exceed 2, a terminal controller can be used alone as the hardware platform of the control system. A terminal controller can be embedded in the sheet metal shell of the device, installed inside the device, or made into a desktop control box.

[0077] When the number of equipment axes and input and output channels exceeds the above limits, the number of controllers can be increased according to the needs. Static and dynamic controllers of different types and numbers can be combined into desktop control boxes or large control cabinets as the hardware platform of the control system. The controllers only need to be connected and communicated to form a whole.

[0078] The desktop control box is a combination of 1-2 controllers, supporting 1-4 axis equipment, and a power supply in one instrument box.

[0079] When there are more than two controllers, they can be installed in one or more standard cabinets together with the power supply after using the panel combination.

[0080] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A combined dynamic and static testing machine controller, the controller cooperates with a computer as a control system of the testing machine, wherein the control system includes at least one controller, characterized in that: The controller can be used alone or in conjunction with a computer as a control system for a uniaxial or biaxial testing machine. Controllers can also be combined using communication protocols and used in conjunction with computers as the control system for the multi-axis testing machine.

2. A combined dynamic and static testing machine controller according to claim 1, characterized in that: Wherein each controller combination method is a distributed topology; In the distributed topology method, each controller is at the same level, and each controller works independently to complete its own measurement, calculation, control, and host communication.

3. A combined dynamic and static testing machine controller according to claim 1, characterized in that: Each controller combination method is a centralized topology; In the centralized topology method, one of the at least two controllers serves as a core machine and communicates with the computer, and the other controllers are logically regarded as the IO part of the controller serving as the core.

4. A combined dynamic and static testing machine controller according to claim 2, characterized in that: Each controller is connected via a static collaborative bus; The protocol of the static cooperative bus is divided into four layers, including transport layer, data packet layer, content layer, and physical layer; the physical layer is standard 485.

5. A combined dynamic and static testing machine controller according to claim 3, characterized in that: Each controller is connected via a static collaborative bus; The collaborative communication between multiple controllers uses a single bus 485, and the collaborative 485 communication ports of all controllers are connected to the same 485 bus.

6. A combined dynamic and static testing machine controller according to claim 3, characterized in that: Each controller is connected through a dynamic collaborative bus; The controller of the core machine is used as a computing power controller and communicates with the computer; other controllers are terminal controllers; the controller collaborative communication interface of the computing power controller includes 1 485 interface and 8 independent 422 interfaces; the 485 interface is used for optional static collaborative connection; each 422 interface can connect to at most one dynamic terminal controller; The controller cooperative communication interface as the terminal controller is a 422 communication interface; the 422 interface of the computing power controller and the terminal controller is a one-to-one connection.

7. A combined dynamic and static testing machine controller according to claim 1, characterized in that: The controller includes a CPU part, an IO part and a communication part.

8. A combined dynamic and static testing machine controller according to claim 7, characterized in that: The CPU part includes a static control unit; Used as a high-speed static control unit; Used as a dynamic control unit; Used as a computing power control unit.

9. A combined dynamic and static testing machine controller according to claim 5 or 6, characterized in that: The communication part includes a host communication interface for communicating with the upper-level computer host, a collaborative communication interface for communicating between peers, and a slave communication interface for communicating with supporting lower-level devices; the host communication interface includes three interface modes: USB interface, Ethernet interface and standard serial port.

10. A combined dynamic and static testing machine controller according to claim 9, characterized in that: The communication protocol of the collaborative bus is divided into 4 layers: transport layer, data packet layer, content layer, and physical layer. Each controller needs to set the collaborative communication parameters in advance, including the local sequence number, the total number of controllers, and the baud rate. The static collaborative communication mode is as follows: Command forwarding mode: The core machine initiates a transmission by sending a command forwarding packet, and the forwarding target controller sends a command reply packet to end the transmission; In this mode, the transmission speed has nothing to do with the measurement and control frequency, but only with the transmission and reception between the computer and the target controller; during this period, all controllers monitor the bus, and irrelevant controllers remain silent; Data transmission mode: The core controller initiates a transmission by sending a start data packet. All controllers take turns sending data packets on the bus according to token passing. The core controller sends an end data packet to end the transmission. Each controller monitors the bus, receives and updates the data content it needs. If no content needs to be sent, a data packet with only a header and a tail is sent to pass the token; In this mode, the collaborative bus transmits an equal amount of data per second according to the measurement and control frequency. For example, when the measurement and control frequency is 40 Hz, the collaborative bus transmits 40 times per second. Since each transmission starts from the core controller with serial number 1, the transmission rate is strictly equal to the measurement and control frequency of the core controller. When no external unified analog sampling clock is used, the measurement and control frequencies of each controller have slight deviations. All controllers determine their own sampling time / sampling serial number based on the core controller. Packet sending mechanism of data transmission mode: Packet sending uses a token mechanism, that is, each controller can send data on the bus only after the token is valid. The token starts from the core controller, is passed in sequence according to the sequence number, and finally returns to the core controller again; The core controller is responsible for the start of the transmission, that is, sending the start data packet, which contains at least the sampling number / sampling time, and all controllers update the sampling beat (sequence number / time) accordingly; After all controllers have finished sending packets, the core machine sends an end data packet; Transport layer token passing rules for static cooperative communication between controllers: Each controller has a unique serial number N; Dynamic collaborative communication methods are as follows: Command forwarding mode: The core machine initiates a transmission, and the target controller sends a command reply packet to end the transmission; In this mode, the transmission speed has nothing to do with the measurement and control frequency, but only with the transmission and reception of the computer and the target controller; during this period, only the 422 bus of the corresponding controller has transmission, and the 422 bus of the irrelevant controller has no transmission; Data transmission mode: The core controller initiates a transmission by sending a start data packet, other controllers send intermediate data packets, and the core controller sends an end data packet to end the transmission; during this period, each 422 bus transmits independently in parallel without affecting each other; In this mode, the transmission speed is strictly consistent with the core machine's measurement and control frequency; Dynamic collaborative packet sending mechanism: Each transmission has three fixed data packets, including the core controller sending the start data packet, other controllers sending the middle data packets, and the core controller sending the end data packet; Error detection and retransmission mechanism: After a controller sends a packet, if other controllers receive it with an error, the bus is immediately pulled down and maintained for 2 bytes of communication time before restoring the bus, and the current controller resends the packet.

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