Ink-jet printing data transmission system based on TSN and ink-jet printing system

Abstract

The invention relates to the technical field of data transmission, in particular to an ink-jet printing data transmission system based on a TSN and an ink-jet printing system.The ink-jet printing data transmission system comprises a time-sensitive network switch used for receiving flow data frames sent by an upper computer; the time-sensitive network gateway is used for receiving the traffic data frame transmitted by the time-sensitive network switch, determining a transmission sequence of all traffic data in a preset transmission time window, and transmitting all processed traffic data; wherein the time-sensitive network gateway mathematical model is constructed based on the flow distribution balance optimization target and the system flow priority distribution optimization target by taking the total size of the flow data received by each electronic control unit as a constraint. According to the invention, the TSN technology is introduced, so that low-delay and high-determinacy data transmission under the condition of high bandwidth is realized in an ink-jet printing system; based on traffic optimization scheduling, a TSN traffic model is designed, a data transmission sequence is determined, and the flexibility and reliability of the system in the data transmission process are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of data transmission, and in particular to an inkjet printing data transmission system and an inkjet printing system based on TSN. Background Art

[0002] Although the existing Ethernet technology has been widely used in industrial communication networks due to its bandwidth advantage of up to 10,000Mb / S, it cannot meet key requirements such as real-time, high bandwidth, and reliability in high-demand industrial applications such as inkjet printing. Specifically, the following problems are encountered:

[0003] (1) Inkjet printing needs to ensure that the delay of data transmission is as low as possible, so as to quickly respond to control commands and transmit image data, and ensure the real-time and smoothness of the printing process. However, the random competition mechanism adopted by the existing Ethernet means that the transmission time of data frames is difficult to predict, and it is impossible to ensure that key data is transmitted within the specified time. This will cause delays and jitters in the data transmission process, which will affect the real-time data interaction and the instant response of control commands, thus affecting the real-time, smoothness and efficiency of the inkjet printing process.

[0004] (2) Inkjet printing requires the data transmission rate to be as high as possible, especially when printing at high resolution, which requires fast transmission of large amounts of data to avoid jamming and delays during printing. However, although existing Ethernet networks have high bandwidth, they are unable to stably provide the required bandwidth in actual applications due to contention for access and network congestion. As a result, stable high-bandwidth transmission cannot be ensured under high load conditions to meet the real-time transmission requirements of high-resolution image data. Printing delays due to data congestion can also affect the real-time performance and reliability of inkjet printing.

[0005] (3) Inkjet printing needs to ensure high reliability during data transmission to avoid data loss or errors, which is crucial for inkjet printing. However, the existing Ethernet does not manage data flows in a sophisticated manner and it is difficult to distinguish the priorities and service quality requirements of different data flows. Therefore, when the network is congested, all data flows will be considered equally important and need to compete equally for bandwidth resources, which will cause delays and packet loss for key data flows, resulting in reduced service quality for key data. In addition, it performs poorly in scenarios where real-time data and best-effort data are transmitted, so that the transmission of real-time data flows cannot be guaranteed, affecting the printing quality, performance and reliability of inkjet printing.

[0006] (4) Inkjet printing requires the use of time synchronization functions to support the simultaneous connection and communication of multiple devices / multiple electronic control units, so as to achieve flexible expansion and management of the network; however, Ethernet lacks precise time synchronization functions and cannot provide time synchronization support for multiple tasks, which easily leads to task execution deviation and uncertainty in the inkjet printing system.

[0007] In summary, the existing Ethernet technology cannot ensure that the delay of data transmission is as low as possible due to the use of a random competition mechanism when transmitting data for inkjet printing applications that require high precision and low latency; it cannot ensure that the data transmission rate is as high as possible due to contention for access and network congestion; it cannot ensure high reliability of data transmission due to the lack of effective management of different data streams; it cannot provide time synchronization support for multiple tasks due to the lack of accurate time synchronization function, which affects the quality, performance, real-time, reliability and efficiency of inkjet printing, making it difficult to meet the stringent requirements for real-time, high bandwidth and reliability of data transmission in industrial applications such as inkjet printing. Summary of the invention

[0008] To this end, the technical problem to be solved by the present invention is to overcome the random competition mechanism adopted in the prior art, which makes it impossible to ensure that the delay of data transmission is as low as possible; due to competition for access and network congestion, it is impossible to ensure that the data transmission rate is as high as possible; there is a lack of effective management of different data streams, and it is impossible to ensure high reliability of data transmission; there is a lack of accurate time synchronization function, and it is impossible to provide time synchronization support for multiple tasks, which leads to problems affecting the quality, performance, real-time, reliability and efficiency of inkjet printing.

[0009] In order to solve the above technical problems, the present invention provides an inkjet printing data transmission system based on a time-sensitive network, comprising: A time-sensitive network switch is connected to the host computer for communication; it is used to receive the flow data frame sent by the host computer; wherein the flow data frame includes a control data frame and a short-width print head image data frame; A time-sensitive network gateway is communicatively connected with a time-sensitive network switch and a plurality of electronic control units; wherein the plurality of electronic control units include a plurality of control nodes and a short-width print head node, the type of flow data in the flow data frame is the same as the number of electronic control units, and each electronic control unit receives flow data of a corresponding type; A data receiving module, used for receiving a flow data frame transmitted by a time-sensitive network switch, and parsing the flow data frame into a flow data set; The traffic scheduling module is used to solve the constructed mathematical model of the time-sensitive network gateway by using a multi-objective optimization algorithm, optimize the scheduling of various traffic data in the traffic data set, and determine the amount of traffic data received by each electronic control unit; according to the preset priority of various types of traffic data and the first-in-first-out principle, determine the transmission order of all traffic data within the preset transmission time window; Wherein, the time-sensitive network gateway mathematical model includes: The optimization objective of flow distribution balance is to minimize the sum of the differences between the total number of flow data received by each electronic control unit and the average flow of all units; The optimization target of system flow priority allocation is to minimize the sum of the priorities of the flow data received by each electronic control unit; Based on the optimization objectives of traffic distribution balance and system traffic priority allocation, and taking the total size of traffic data received by each electronic control unit as a constraint, a mathematical model of a time-sensitive network gateway is constructed. The data transmission module is used to aggregate various control data in the traffic data set into multiple CAN frames, and distribute the multiple CAN frames to their corresponding control nodes in the transmission order; and send each short-width printing nozzle image data in the traffic data set to the short-width printing nozzle node in the transmission order.

[0010] Preferably, the flow distribution balance optimization target is to minimize the sum of the differences between the total amount of flow data received by each electronic control unit and the average flow of all units, and its expression is: ; in, It represents the optimization goal of traffic distribution balance; Indicates the number of electronic control units, based on which each electronic control unit receives its corresponding type of flow data, It is also characterized by the number of types of flow data; Indicates the index of the electronic control unit, and also represents the type index of the flow data. ; Indicates The number of flow data received by each electronic control unit; Indicates The weight of class traffic data; represents the average flow of all units, and its expression is: .

[0011] Preferably, the minimum sum of the priorities of the flow data received by each electronic control unit is used as the optimization target of the system flow priority allocation, and its expression is: ; in, Indicates the optimization target of system traffic priority allocation; Indicates the number of electronic control units, based on which each electronic control unit receives its corresponding type of flow data, It is also characterized as the type of flow data; Indicates the index of the electronic control unit, and also represents the type index of the flow data. ; Indicates The number of flow data received by each electronic control unit; Indicates The order weight of the electronic control units receiving the flow data; Indicates Normalized vector of class traffic data.

[0012] Preferably, the constructing of a time-sensitive network gateway mathematical model comprises: ; ; in, It represents the optimization goal of traffic distribution balance; Indicates the optimization target of system traffic priority allocation; represents the average flow rate of all units; Indicates the number of electronic control units, based on which each electronic control unit receives its corresponding type of flow data, It is also characterized by the number of types of flow data; Indicates the index of the electronic control unit, and also represents the type index of the flow data. ; Indicates The number of flow data received by each electronic control unit; Indicates The weight of class traffic data; Indicates The order weight of the electronic control units receiving the flow data; Indicates Normalized vector of class traffic data; Indicates The size of class traffic data; Indicates the maximum value of the traffic allowed within the preset transmission time window.

[0013] Preferably, the control node includes: a temperature control sensor, a conveyor belt encoder, a UV light control and a pressure sensor.

[0014] The present invention also provides an inkjet printing system based on a time-sensitive network, comprising:

[0015] The host computer, as a control unit, is used to send traffic data frames;

[0016] The time-sensitive network main switch is connected to the host computer for communication, and is used to receive the flow data frame and the wide-format printing nozzle image data frame sent by the host computer, and transmit the flow data frame and the wide-format printing nozzle image data frame to its corresponding time-sensitive network secondary switch;

[0017] A plurality of groups of inkjet printing sub-devices, each group of inkjet printing sub-devices comprising:

[0018] The time-sensitive network secondary switch is connected to the time-sensitive network main switch in communication; and is used to receive the flow data frame and the wide-format printing nozzle image data frame transmitted by the time-sensitive network main switch;

[0019] The time-sensitive network gateway is connected to the time-sensitive network sub-switch and multiple electronic control units in communication; it is used to use the data receiving module to receive the flow data frame transmitted by the time-sensitive network sub-switch; use the flow scheduling module to determine the transmission order of all flow data in the preset transmission time window; use the data transmission module to aggregate various control data in the flow data set into multiple CAN frames, and distribute the multiple CAN frames to their corresponding control nodes according to the transmission order; send each short-width print head image data in the flow data set to the short-width print head node according to the transmission order;

[0020] Multiple electronic control units, including multiple control nodes and a short-width printing nozzle node; each control node is used to receive multiple CAN frames corresponding to it and execute the control task corresponding to each CAN frame; the short-width printing nozzle node receives image data of each short-width printing nozzle and performs short-width printing;

[0021] The data parsing module is connected to the time-sensitive network sub-switch and the wide-format print head module; it is used to receive the wide-format print head image data frame transmitted by the time-sensitive network sub-switch, and parse the wide-format print head image data frame into a wide-format print head image data set; and send each wide-format print head image cropped from the wide-format print head image data set to the wide-format print head module;

[0022] The wide-format printing nozzle module is used to receive the cropped wide-format printing nozzle images and perform wide-format printing.

[0023] Preferably, it also includes:

[0024] The task monitoring main module is connected to the time-sensitive network gateway of the first inkjet printing sub-device; it is responsible for monitoring the faults of each electronic control unit in the first inkjet printing sub-device, receiving the fault information in other inkjet printing sub-devices, uploading all the fault information to the time-sensitive network gateway of the first inkjet printing sub-device, and then reporting to the host computer through the time-sensitive network gateway of the first inkjet printing sub-device, the time-sensitive network secondary switch and the time-sensitive network main switch;

[0025] Multiple task monitoring slave modules, each of which is connected to the time-sensitive network gateway of its corresponding inkjet printing sub-device and the task monitoring main module; it is responsible for fault monitoring of each electronic control unit in its corresponding inkjet printing sub-device and transmitting the fault information to the task monitoring main module.

[0026] Preferably, each group of inkjet printing sub-devices further includes:

[0027] The infrared sensor is connected to the time-sensitive network gateway for communication; it is used to detect the position of the printing paper and sense the paper entering the inkjet printing sub-device, thereby controlling the operation of the inkjet printing sub-device.

[0028] The above technical solution of the present invention has the following beneficial effects compared with the prior art:

[0029] (1) The inkjet printing data transmission system based on TSN described in the present invention utilizes the time scheduling technology of time-sensitive streams in the time-sensitive network (TSN) to allow high-priority data streams to monopolize bandwidth within a unit time to ensure stability in real-time transmission; utilizes the traffic filtering and traffic shaping technology in the time-sensitive network to set transmission rules and bandwidth restrictions for data streams of different priorities and optimize the processing order of data streams; therefore, priority scheduling and traffic shaping can be implemented in the time-sensitive network, effectively reducing the delay of data in the transmission process, thereby ensuring that real-time control data and image data can arrive in time, improving the response speed of the inkjet printing data transmission process, and ensuring the real-time performance of the inkjet printing system;

[0030] (2) The inkjet printing data transmission system based on TSN described in the present invention optimizes the bandwidth allocation strategy based on the time-aware traffic shaping mechanism in the time-sensitive network, that is, through the time-sensitive network switch, the sending rate of the data flow is controlled to avoid network congestion, and the data frames can be classified according to the priority of different data flows, so that important data flows are sent first to ensure that the transmission of key data is not affected, so that data flows with high bandwidth requirements, such as high-resolution image data, can be given priority, ensuring that the inkjet printing system can run stably when all tasks are carried out simultaneously, thereby improving the reliability, printing quality and efficiency of the inkjet printing system;

[0031] (3) The inkjet printing data transmission system based on TSN described in the present invention constructs a time-sensitive network gateway mathematical model in the time-sensitive network gateway, and uses a multi-objective optimization algorithm to solve the amount of traffic data received by each electronic control unit, and then determines the transmission order of various traffic data according to the preset priorities of various traffic data and the first-in-first-out principle; the time-sensitive network gateway containing the time-sensitive network gateway mathematical model can intelligently identify and manage different types of data streams, dynamically adjust according to their priorities and service quality requirements, ensure the transmission time limit of real-time data streams, and ensure that key tasks obtain sufficient network resources, thereby improving the performance and reliability of the inkjet printing system;

[0032] (4) The TSN-based inkjet printing data transmission system described in the present invention utilizes the clock synchronization function in the time-sensitive network to ensure that the global time of each electronic control unit in the inkjet printing system remains consistent during the data transmission process, thereby achieving higher-precision data processing and task coordination, thereby ensuring the determinism of the execution of data transmission tasks in the inkjet printing system. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein:

[0034] Figure 1 It is a schematic diagram of an inkjet printing data transmission system based on a time-sensitive network provided by the present invention;

[0035] Figure 2 is a schematic diagram of an inkjet printing system based on a time-sensitive network provided by the present invention;

[0036] Figure 3 is the end-to-end delay graph of BE flows with different gateway configuration scenarios;

[0037] Figure 4 is the end-to-end delay graph of TT flows with different gateway configuration scenarios;

[0038] Figure 5 It is a schematic diagram of four types of traffic data for the optimal solution. DETAILED DESCRIPTION

[0039] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0040] Example 1

[0041] Reference Figure 1 As shown, Figure 1A schematic diagram of an inkjet printing data transmission system based on a time-sensitive network corresponding to the embodiment 1 provided by the present invention; specifically comprising:

[0042] A time-sensitive network switch is connected to the host computer for communication; it is used to receive the flow data frame sent by the host computer; wherein the flow data frame includes a control data frame and a short-width print head image data frame;

[0043] A time-sensitive network gateway is communicatively connected with a time-sensitive network switch and a plurality of electronic control units; wherein the plurality of electronic control units include a plurality of control nodes and a short-width print head node, the type of flow data in the flow data frame is the same as the number of the electronic control units, and each electronic control unit receives flow data of a corresponding type; in a specific embodiment of the present invention, the control node includes: a temperature control sensor, a conveyor belt encoder, a UV light control, and a pressure sensor;

[0044] A data receiving module, used for receiving a flow data frame transmitted by a time-sensitive network switch, and parsing the flow data frame into a flow data set;

[0045] The traffic scheduling module is used to solve the constructed mathematical model of the time-sensitive network gateway by using a multi-objective optimization algorithm, optimize the scheduling of various traffic data in the traffic data set, and determine the amount of traffic data received by each electronic control unit; according to the preset priority of various types of traffic data and the first-in-first-out principle, determine the transmission order of all traffic data within the preset transmission time window;

[0046] Wherein, the time-sensitive network gateway mathematical model includes:

[0047] The optimization objective of flow distribution balance is to minimize the sum of the differences between the total number of flow data received by each electronic control unit and the average flow of all units. The expression is: ; in, It represents the optimization goal of traffic distribution balance; Indicates the number of electronic control units, based on which each electronic control unit receives its corresponding type of flow data, It is also characterized by the number of types of flow data; Indicates the index of the electronic control unit, and also represents the type index of the flow data. ; Indicates The number of flow data received by each electronic control unit; Indicates The weight of class traffic data; represents the average flow of all units, and its expression is: ;

[0048] The optimization objective of system flow priority allocation is to minimize the sum of the priorities of the flow data received by each electronic control unit. The expression is: ; in, Indicates the optimization target of system traffic priority allocation; Indicates the number of electronic control units, based on which each electronic control unit receives its corresponding type of flow data, It is also characterized as the type of flow data; Indicates the index of the electronic control unit, and also represents the type index of the flow data. ; Indicates The number of flow data received by each electronic control unit; Indicates The order weight of the electronic control units receiving the flow data; Indicates Normalized vector of class traffic data

[0049] Based on the optimization objectives of traffic distribution balance and system traffic priority allocation, and taking the total size of traffic data received by each electronic control unit as a constraint, a mathematical model of a time-sensitive network gateway is constructed, including: ; ; in, It represents the optimization goal of traffic distribution balance; Indicates the optimization target of system traffic priority allocation; represents the average flow rate of all units; Indicates the number of electronic control units, based on which each electronic control unit receives its corresponding type of flow data, It is also characterized by the number of types of flow data; Indicates the index of the electronic control unit, and also represents the type index of the flow data. ; Indicates The number of flow data received by each electronic control unit; Indicates The weight of class traffic data; Indicates The order weight of the electronic control units receiving the flow data; Indicates Normalized vector of class traffic data; Indicates The size of class traffic data; Indicates the maximum value of the allowed flow rate within the preset transmission time window;

[0050] The data transmission module is used to aggregate various control data in the traffic data set into multiple CAN frames, and distribute the multiple CAN frames to their corresponding control nodes in the transmission order; and send each short-width printing nozzle image data in the traffic data set to the short-width printing nozzle node in the transmission order.

[0051] Table 1 summarizes the types of main flow data of the inkjet printing system when it is working. The start sending time records the time point when each control flow starts to send after the system is powered on, and the data size is normalized.

[0052] Table 1 Data table related to different flow data

[0053]

[0054] In actual scenarios, multiple printing devices need to collaborate in an orderly manner, and the balance of traffic allocated by the gateway to each node is a key indicator; therefore, the delay difference of data received by multiple printers is used as the objective function, and the total traffic received by each node must also be considered.

[0055] When the printing device is working, it is very important to ensure that the working order of each module is accurate. First, the speed of the conveyor belt encoder needs to be set in advance. After the conveyor belt is started, the temperature control module enters the working state; then, the node starts to process the image data sent by the host computer; finally, the nozzle starts to perform the printing task according to the predetermined parameters; therefore, ensuring the correct working order of the ECU modules of a single printing device is a key factor in improving the overall printing speed.

[0056] Three performance indicators are used as evaluation criteria: end-to-end delay, network throughput, and task flow transmission interval; end-to-end delay consists of propagation delay, link transmission delay, and processing delay of each part; network throughput is the number of data packets received by the terminal node per unit time. The larger the packet size, the higher the throughput. The larger the packet size, the more network congestion will be caused, resulting in increased delay. Therefore, it is used as the main performance indicator; the transmission interval is the minimum sending interval of the task flow. Under the condition that the link bandwidth is 1Gbps, the task flow can improve its sending efficiency as much as possible and improve the operating efficiency of the overall equipment.

[0057] Example 2

[0058] Reference Figure 2 As shown, Figure 2 A schematic diagram of an inkjet printing data transmission system based on a time-sensitive network corresponding to the second embodiment of the present invention; specifically comprising:

[0059] The host computer, as a control unit, is used to send traffic data frames;

[0060] The time-sensitive network main switch is connected to the host computer for communication, and is used to receive the flow data frame and the wide-format printing nozzle image data frame sent by the host computer, and transmit the flow data frame and the wide-format printing nozzle image data frame to its corresponding time-sensitive network secondary switch;

[0061] A plurality of groups of inkjet printing sub-devices, each group of inkjet printing sub-devices comprising:

[0062] The time-sensitive network secondary switch is connected to the time-sensitive network main switch in communication; and is used to receive the flow data frame and the wide-format printing nozzle image data frame transmitted by the time-sensitive network main switch;

[0063] The time-sensitive network gateway is connected to the time-sensitive network sub-switch and multiple electronic control units in communication; it is used to use the data receiving module to receive the flow data frame transmitted by the time-sensitive network sub-switch; use the flow scheduling module to determine the transmission order of all flow data in the preset transmission time window; use the data transmission module to aggregate various control data in the flow data set into multiple CAN frames, and distribute the multiple CAN frames to their corresponding control nodes according to the transmission order; send each short-width print head image data in the flow data set to the short-width print head node according to the transmission order;

[0064] Multiple electronic control units, including multiple control nodes and a short-width printing nozzle node; each control node is used to receive multiple CAN frames corresponding to it and execute the control task corresponding to each CAN frame; the short-width printing nozzle node receives image data of each short-width printing nozzle and performs short-width printing;

[0065] An infrared sensor is connected to the time-sensitive network gateway for communication; it is used to detect the position of the printing paper and sense the paper entering the inkjet printing sub-device, thereby controlling the operation of the inkjet printing sub-device;

[0066] The data parsing module is connected to the time-sensitive network sub-switch and the wide-format print head module; it is used to receive the wide-format print head image data frame transmitted by the time-sensitive network sub-switch, and parse the wide-format print head image data frame into a wide-format print head image data set; and send each wide-format print head image cropped from the wide-format print head image data set to the wide-format print head module;

[0067] A wide-format printing nozzle module is used to receive the cropped images of each wide-format printing nozzle and perform wide-format printing;

[0068] The task monitoring main module is connected to the time-sensitive network gateway of the first inkjet printing sub-device; it is responsible for monitoring the faults of each electronic control unit in the first inkjet printing sub-device, receiving the fault information in other inkjet printing sub-devices, uploading all the fault information to the time-sensitive network gateway of the first inkjet printing sub-device, and then reporting to the host computer through the time-sensitive network gateway of the first inkjet printing sub-device, the time-sensitive network secondary switch and the time-sensitive network main switch;

[0069] Multiple task monitoring slave modules, each of which is connected to the time-sensitive network gateway of its corresponding inkjet printing sub-device and the task monitoring main module; it is responsible for fault monitoring of each electronic control unit in its corresponding inkjet printing sub-device and transmitting the fault information to the task monitoring main module.

[0070] Based on the improved multi-objective optimization algorithm, the four types of traffic data corresponding to the Pareto coordination optimal solution are sent to the terminal node through workstation 1, with a sending interval of 12us. The size of each data stream is the size of four traffic data * the calculated number of data, which will be controlled within 1500B according to the constraints; the PCP value of each type of traffic data is shown in Table 1; by configuring the gating linked list GCL of TSN-CANGateway, the time-sensitive network frame needs to wait for the corresponding gateway to be opened before the forwarding process can be completed, and this process is used to simulate the scheduling capability of the gateway; the switching time of GCL is shown in Table 2; the experiment of the present invention sets up two different sets of GCL, configuration 1 is the gateway gating full-open mode, that is, no scheduling is required, and all traffic is first-in-first-out in the order of input from the gateway; configuration 2 is the gateway scheduling mode, according to the gated switching time calculated by the scheduling algorithm.

[0071] Table 2 GCL switching schedule

[0072]

[0073] The present invention uses "O" to represent the open state and "C" to represent the closed state; according to the IEEE 802.1Q standard, the high bit of the 8-bit gate state corresponds to a high priority, that is: the first bit on the left represents priority 7, and the first bit on the right represents priority 0; if the gateway's gating is in the starting state "COOOOCCC", it means that four types of traffic data with PCP of 6, 5, 4 and 3 can be forwarded directly, while four types of traffic data of 7, 2, 1 and 0 are blocked from forwarding and need to wait to enter the next gating state.

[0074] Figure 3: In the figure, the end-to-end delay E2E delay obtained at the device1 node after the simulation scenario of the present invention is composed of three parts: propagation delay, link transmission delay and processing delay of each module; when the gateway is in the default configuration 1, the four types of traffic data are all transmitted using BE flow, and the link is blocked by jitter and traffic fragmentation during the transmission process, so the delay is up to 740us; but when the gateway is configured to 2, the congestion level of the traffic is effectively controlled during the transmission process. When the transmission reaches the peak, the average end-to-end delay is 350us, and it shows a certain periodicity.

[0075] Figure 4 It shows that the present invention changes the type of control flow of the conveyor encoder from BE to TT time-triggered flow. When the gateway is in the default configuration 1, the time-triggered flow is affected by jitter and link blocking caused by best-effort fragmentation during transmission, resulting in an average end-to-end delay of 40us. If the gateway scheduling strategy is used, the end-to-end delay of the TT flow can be effectively alleviated; the error bar represents the 95% confidence interval; Table 3 shows the specific values ​​of the end-to-end delay of four types of traffic data.

[0076] Table 3 Specific values ​​of end-to-end delay for four types of traffic data

[0077] Flow Type Mean Max Min Gateway-OFF BE Flow 71636e-4 74606e-4 39217e-4 Gateway-ON BE Flow 35426e-4 40015e-4 11235e-4 Gateway-OFF TT Flow 40223e-5 40424e-5 40084e-5 Gateway-ON TT Flow 31916e-5 32414e-5 31512e-5

[0078] Another performance indicator is the number of packets received by the terminal node per unit time, that is, the number of packets that reach device1 through the link within 1 second of the nested simulation run, which reflects the network throughput. In the simulation, the number of packets increases linearly with time. The peak value of packets after 1 second is taken to obtain Figure 5 The conclusion is that the most packets are received when using one TT flow + three BE flows, followed by four BE control flows scheduled by the gateway, and the least are four packets not scheduled by the gateway.

[0079] The present invention solves the problem of insufficient real-time and deterministic performance of traditional Ethernet by adopting time-sensitive network (TSN) technology, ensuring that key data streams are transmitted within a predetermined time window, greatly reducing delay and jitter problems, and meeting the inkjet printing system's requirements for low-latency and high-deterministic data transmission; utilizing the time scheduling mechanism, time-aware traffic shaping, clock synchronization, and priority scheduling of the time-sensitive network to ensure real-time transmission of key data streams and network synchronization, thereby improving the determinism of overall network transmission.

[0080] The present invention introduces a priority scheduling function to reasonably allocate bandwidth resources according to the importance and urgency of data flows, avoid bandwidth waste and ensure priority transmission of key data, thereby improving overall transmission efficiency; in particular, when processing multi-task parallel data transmission, bandwidth utilization is significantly improved; using the bandwidth reservation and priority scheduling mechanism of the time-sensitive network, various types of data flows are dynamically managed and scheduled to ensure that high-priority data flows can be transmitted on time even under congestion conditions.

[0081] The present invention uses the traffic shaping function of the time-sensitive network to prioritize data streams and reserve bandwidth, optimize the bandwidth utilization of multi-task parallel data streams, ensure the timely completion of key tasks, and improve data transmission efficiency; the time-aware traffic shaping technology of the time-sensitive network realizes the function of dynamically allocating bandwidth resources, ensuring the high efficiency of data stream transmission and the maximum utilization of network resources.

[0082] The present invention applies time-sensitive network technology to data transmission in industrial inkjet printing. Through a reasonable scheduling mechanism and gateway management method, it effectively alleviates network congestion problems in high-traffic transmission scenarios, avoids data backlog and transmission delays in traditional Ethernet under high load conditions, and solves the delay and bandwidth bottleneck problems that occur in traditional networks during data transmission. In the inkjet printing system, a time-sensitive network is used to implement a data transmission solution with low latency, high certainty and bandwidth optimization, ensuring reliability and stability during data transmission.

[0083] The present invention designs an optimized gateway management mechanism for data transmission between TSN and CAN buses, that is, by classifying and scheduling a variety of different types of data streams, it ensures that the system can be dynamically adjusted according to different task requirements, thereby improving the flexibility of data transmission; at the same time, the high deterministic transmission capability of the time-sensitive network enables data to be transmitted stably and reliably in a complex network environment, ensuring the overall reliability of the system and ensuring seamless and efficient data transmission between different networks; in the TSN-CAN gateway, the scheduling mechanism and traffic shaping technology of TSN are used to solve the delay and congestion problems in data transmission, thereby ensuring efficient collaboration between different networks.

[0084] The present invention realizes accurate time synchronization of each node in the inkjet printing system through the clock synchronization function of TSN, ensuring the synchronization and certainty of task execution; and utilizes the clock synchronization technology of TSN to ensure the global time consistency of each node in the system during data transmission, thereby achieving higher-precision data processing and task coordination.

[0085] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. An inkjet printing data transmission system based on TSN, characterized in that: include: A time-sensitive network switch is connected to the host computer for communication; Used to receive the flow data frame sent by the host computer; wherein the flow data frame includes a control data frame and a short-width print head image data frame; A time-sensitive network gateway is communicatively connected with a time-sensitive network switch and a plurality of electronic control units; wherein the plurality of electronic control units include a plurality of control nodes and a short-width print head node, the type of flow data in the flow data frame is the same as the number of electronic control units, and each electronic control unit receives flow data of a corresponding type; A data receiving module, used for receiving a flow data frame transmitted by a time-sensitive network switch, and parsing the flow data frame into a flow data set; The traffic scheduling module is used to solve the constructed mathematical model of the time-sensitive network gateway by using a multi-objective optimization algorithm, optimize the scheduling of various traffic data in the traffic data set, and determine the amount of traffic data received by each electronic control unit; according to the preset priority of various types of traffic data and the first-in-first-out principle, determine the transmission order of all traffic data within the preset transmission time window; Wherein, the time-sensitive network gateway mathematical model includes: The optimization objective of flow distribution balance is to minimize the sum of the differences between the total number of flow data received by each electronic control unit and the average flow of all units; The optimization goal of system flow priority allocation is to minimize the sum of the priorities of the flow data received by each electronic control unit; Based on the optimization objectives of traffic distribution balance and system traffic priority allocation, and taking the total size of traffic data received by each electronic control unit as a constraint, a mathematical model of a time-sensitive network gateway is constructed. The data transmission module is used to aggregate various control data in the traffic data set into multiple CAN frames, and distribute the multiple CAN frames to their corresponding control nodes in the transmission order; and send each short-width printing nozzle image data in the traffic data set to the short-width printing nozzle node in the transmission order.

2. The inkjet printing data transmission system based on TSN according to claim 1, characterized in that: The flow distribution balance optimization target is to minimize the sum of the differences between the total amount of flow data received by each electronic control unit and the average flow of all units, and its expression is: ； in, It represents the optimization goal of traffic distribution balance; Indicates the number of electronic control units, based on which each electronic control unit receives its corresponding type of flow data, It is also characterized by the number of types of flow data; Indicates the index of the electronic control unit, and also represents the type index of the flow data. ; Indicates The number of flow data received by each electronic control unit; Indicates The weight of class traffic data; represents the average flow of all units, and its expression is: .

3. The inkjet printing data transmission system based on TSN according to claim 1, characterized in that: The system flow priority allocation optimization target is to minimize the sum of the priorities of the flow data received by each electronic control unit, and its expression is: ； in, Indicates the optimization target of system traffic priority allocation; Indicates the number of electronic control units, based on which each electronic control unit receives its corresponding type of flow data, It is also characterized as the type of flow data; Indicates the index of the electronic control unit, and also represents the type index of the flow data. ; Indicates The number of flow data received by each electronic control unit; Indicates The order weight of the electronic control units receiving the flow data; Indicates Normalized vector of class traffic data.

4. The inkjet printing data transmission system based on TSN according to claim 1, characterized in that: The construction of the time-sensitive network gateway mathematical model includes: ； ； in, It represents the optimization goal of traffic distribution balance; Indicates the optimization target of system traffic priority allocation; represents the average flow rate of all units; Indicates the number of electronic control units, based on which each electronic control unit receives its corresponding type of flow data, It is also characterized by the number of types of flow data; Indicates the index of the electronic control unit, and also represents the type index of the flow data. ; Indicates The number of flow data received by each electronic control unit; Indicates The weight of class traffic data; Indicates The order weight of the electronic control units receiving the flow data; Indicates Normalized vector of class traffic data; Indicates The size of class traffic data; Indicates the maximum value of the traffic allowed within the preset transmission time window.

5. The inkjet printing data transmission system based on TSN according to claim 1, characterized in that: The control node includes: temperature control sensor, conveyor belt code, UV light control and pressure sensor.

6. An inkjet printing system based on a time-sensitive network, characterized in that: include: The host computer, as a control unit, is used to send traffic data frames; The time-sensitive network main switch is connected to the host computer for communication, and is used to receive the flow data frame and the wide-format printing nozzle image data frame sent by the host computer, and transmit the flow data frame and the wide-format printing nozzle image data frame to its corresponding time-sensitive network secondary switch; A plurality of groups of inkjet printing sub-devices, each group of inkjet printing sub-devices comprising: The time-sensitive network secondary switch is connected to the time-sensitive network main switch for communication; and is used to receive the flow data frame and the wide-format printing nozzle image data frame transmitted by the time-sensitive network main switch; The time-sensitive network gateway is connected to the time-sensitive network sub-switch and multiple electronic control units in communication; it is used to use the data receiving module to receive the flow data frame transmitted by the time-sensitive network sub-switch; use the flow scheduling module to determine the transmission order of all flow data in the preset transmission time window; use the data transmission module to aggregate various control data in the flow data set into multiple CAN frames, and distribute the multiple CAN frames to their corresponding control nodes according to the transmission order; send each short-width print head image data in the flow data set to the short-width print head node according to the transmission order; Multiple electronic control units, including multiple control nodes and a short-width printing nozzle node; each control node is used to receive multiple CAN frames corresponding to it and execute the control task corresponding to each CAN frame; the short-width printing nozzle node receives image data of each short-width printing nozzle and performs short-width printing; The data parsing module is connected to the time-sensitive network sub-switch and the wide-format print head module; it is used to receive the wide-format print head image data frame transmitted by the time-sensitive network sub-switch, and parse the wide-format print head image data frame into a wide-format print head image data set; and send each wide-format print head image cropped from the wide-format print head image data set to the wide-format print head module; The wide-format printing nozzle module is used to receive the cropped wide-format printing nozzle images and perform wide-format printing.

7. The TSN-based inkjet printing system according to claim 6, characterized in that: Also includes: A task monitoring main module connected to a time-sensitive network gateway of the first inkjet printing sub-device; It is responsible for monitoring the faults of each electronic control unit in the first inkjet printing sub-device, receiving the fault information in other inkjet printing sub-devices, uploading all the fault information to the time-sensitive network gateway of the first inkjet printing sub-device, and then reporting to the host computer through the time-sensitive network gateway, the time-sensitive network secondary switch and the time-sensitive network main switch of the first inkjet printing sub-device; Multiple task monitoring slave modules, each of which is connected to the time-sensitive network gateway of its corresponding inkjet printing sub-device and the task monitoring main module; it is responsible for fault monitoring of each electronic control unit in its corresponding inkjet printing sub-device and transmitting the fault information to the task monitoring main module.

8. The TSN-based inkjet printing system according to claim 6, characterized in that: Each set of inkjet printing sub-devices also includes: The infrared sensor is connected to the time-sensitive network gateway for communication; it is used to detect the position of the printing paper and sense the paper entering the inkjet printing sub-device, thereby controlling the operation of the inkjet printing sub-device.

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