Reciprocating type high-speed ink-jet printing path optimization method based on time-space synchronization control

Abstract

The invention discloses a space-time synchronization control-based reciprocating high-speed ink-jet printing path optimization method and a related device. The method comprises the following steps of: generating an ignition pulse density map according to a CIP4 file; and according to the nozzle layout and the density map, starting and ending coordinates, parking cooling time, an overlapping area and feathering transition width of a scanning strip are planned. Real-time position, speed, acceleration and inertia parameters are fused through a motion trail predictor, and the future motion trail of the nozzle is predicted; and the drop point space-time offset is calculated by combining the ink droplet flight time compensation model and the piezoelectric hysteresis effect coefficient. And according to deviation, offset, ignition frequency limitation and crosstalk parameters, a self-adaptive dynamic scanning path is generated, a scanning strip is dynamically divided into three sections including acceleration pilot injection, uniform-speed fine beating and deceleration recovery, and an S-shaped reversing curve and micro return difference compensation are embedded. A gradient ignition waveform subjected to temperature compensation is generated, and the state of the spray hole is monitored in real time through feedback voltage. The printing stroke utilization rate and the splicing quality are improved.

Description

Technical Field

[0001] This invention relates to the field of digital inkjet printing technology, specifically to a method and apparatus for optimizing reciprocating high-speed inkjet printing paths based on spatiotemporal synchronization control, and a computing device. Background Technology

[0002] High-speed inkjet printing technology is gradually replacing traditional analog printing methods due to its advantages such as non-contact operation and on-demand ink supply. In industrial applications, reciprocating scanning printing (where the printhead moves back and forth along the X-axis and the media moves along the Y-axis) is widely used due to its compact structure and controllable cost. However, under high-speed operation, it is susceptible to interference from multiple factors such as mechanical vibration, acceleration and deceleration dynamic response, printhead thermal drift, droplet flight deviation, and multi-printhead splicing errors. This can lead to defects in the image, such as streaks, misalignment, uneven density, white gaps, or crosstalk artifacts, which seriously affect the yield and visual quality of the finished product.

[0003] Traditional methods rely heavily on static calibration and fixed path planning, which are difficult to cope with real-time disturbances under dynamic operating conditions. To solve the above problems, this invention proposes a reciprocating high-speed inkjet printing path optimization method based on spatiotemporal synchronization control to improve printing stroke utilization and splicing quality. Summary of the Invention

[0004] In view of the above problems, the present invention provides a method, apparatus and computing device for optimizing reciprocating high-speed inkjet printing path based on spatiotemporal synchronization control.

[0005] According to one aspect of the present invention, a method for optimizing the path of a reciprocating high-speed inkjet printing system based on spatiotemporal synchronization control is provided, comprising: The ignition pulse density map for each nozzle is generated based on the CIP4 digital workflow file of the image to be printed. Each pixel in the ignition pulse density map includes an absolute coordinate vector, a gray level value, and a channel identifier. Based on the linear array layout of the nozzles on the printhead chassis, the staggered offset of the printhead module, and the ignition pulse density map, the starting absolute coordinates, ending absolute coordinates, the dwell time threshold of the printhead when the strip changes direction, the overlapping coverage area between the scan strips, and the feathering transition width are calculated for each scan strip. The real-time position coordinates, instantaneous velocity, instantaneous acceleration, mass inertia parameters of the printhead module, and thrust fluctuation coefficient of the linear motor are input into the motion trajectory predictor to predict the printhead's motion trajectory curve over multiple future sampling periods. The starting absolute coordinates, ending absolute coordinates, printhead dwell cooling time threshold during strip reversal, overlapping coverage area between scan strips, feathering transition width, and predicted motion trajectory curve of each scan strip are input into the spatiotemporal synchronization processor to construct the dynamic deviation tensor between the target spatial coordinates of all executable printing units within the current scan strip and the predicted arrival position of the printhead. Based on the time-of-flight compensation model of ink droplets during the ejection process and the piezoelectric crystal hysteresis effect coefficient of the printhead during acceleration and deceleration, the actual landing point time offset and actual landing point spatial offset of the ink droplets from the nozzle to the substrate surface are calculated. Based on the dynamic deviation tensor, actual landing point spatial offset, printhead maximum firing frequency limit, and crosstalk suppression parameters between nozzles, an adaptive dynamic scanning path is generated for the current scanning strip to eliminate streak defects caused by printhead speed fluctuations and splicing misalignment caused by mechanical backlash. The adaptive dynamic scanning path and the grayscale level value of each executable printing unit are input to the waveform generation unit to generate a gradient firing waveform signal adapted to the piezoelectric printhead. The gradient firing waveform signal is temperature compensated and corrected based on the real-time temperature value fed back by the printhead temperature sensor to ensure the consistency of ink droplet volume and velocity at different temperatures. The gradient ignition waveform signal is transmitted to the FPGA logic unit of the nozzle control board through a high-speed serial interface. The FPGA logic unit triggers the ignition operation of the corresponding nozzle at the precise spatiotemporal coordinate point after dynamic deviation tensor correction according to the timing node of the adaptive dynamic scanning path planning, and completes the printing task of the current scanning strip. The feedback voltage signal of the nozzle is used to determine whether there is a blocked nozzle or an abnormal nozzle, and the nozzle status data is updated to the ignition pulse density map in real time. For abnormal nozzles, the neighboring nozzles are used for compensation printing.

[0006] In one alternative approach, generating an ignition pulse density map for each nozzle based on a CIP4 digital workflow file of the image to be printed further includes: Obtain the CIP4 digital workflow file of the image to be printed, and parse the CIP4 digital workflow file using a RIP raster image processor to generate a digital matrix of printing areas including the four CMYK color channels; The digital matrix of the printing area is matched with the physical resolution parameters of the nozzle to generate an ignition pulse density map corresponding to each nozzle.

[0007] In one alternative approach, calculating the starting absolute coordinates, ending absolute coordinates, nozzle dwell-cooling time threshold during strip reversal, overlapping coverage area between scan strips, and feathering transition width for each scan strip further includes: Based on the linear array layout of the nozzles on the nozzle chassis, the staggered offset of the nozzle modules, and the ignition pulse density map, the printing area is divided into several parallel scanning strips along the media feed direction. Assign a strip index number to each scan strip and calculate the starting absolute coordinates, ending absolute coordinates, and the dwell time threshold of the nozzle when the strip changes direction for each scan strip; The overlapping coverage area and feathering transition width between scanning strips are determined based on the splicing error compensation value between the physical width of the nozzle and adjacent nozzles.

[0008] In one alternative approach, the predicted motion trajectory curves of the nozzle over multiple future sampling periods further include: The orthogonal coded pulse signal output by the grating ruler feedback system is acquired in real time. The orthogonal coded pulse signal is subjected to a fourth frequency harmonic processing by the motion controller to calculate the real-time position coordinates, instantaneous motion velocity and instantaneous acceleration of the nozzle module in the X-axis scanning direction. The real-time position coordinates, instantaneous velocity, instantaneous acceleration, mass inertia parameters of the nozzle module, and thrust fluctuation coefficient of the linear motor are input into the motion trajectory predictor to predict the motion trajectory curve of the nozzle in multiple future sampling periods. The predicted motion trajectory curve includes the predicted position sequence, predicted velocity sequence, and predicted acceleration sequence corresponding to the timestamp.

[0009] In one alternative approach, the adaptive dynamic scanning path includes segmented motion control parameters for the pre-spray compensation interval of the printhead in the acceleration phase, the normal spray interval in the constant speed phase, and the residual ink recovery interval in the deceleration phase, as well as S-shaped acceleration / deceleration curve parameters and reverse gap compensation parameters at the reversal points at both ends of the scanning strip. The gradient ignition waveform signal includes voltage amplitude step parameters that control the droplet volume, trigger delay time that controls the droplet ejection phase, and pulse width modulation curve that controls the droplet breakage velocity.

[0010] In one alternative approach, the calculation of the actual landing point time offset and actual landing point spatial offset of the ink droplet from the nozzle to the substrate surface, based on the time-of-flight compensation model of the ink droplet during the ejection process and the piezoelectric crystal hysteresis coefficient of the printhead during the acceleration and deceleration phases, further includes: With the nozzle module stationary, a set of stepped scanning voltage signals covering the entire voltage range are applied to the test nozzle of the piezoelectric nozzle. The mechanical displacement response curves of the piezoelectric crystal under different voltage excitations are collected by a laser Doppler vibration meter installed below the nozzle. The mechanical displacement response curves are differentiated to extract the displacement voltage hysteresis loop characteristic parameters of the piezoelectric crystal at the rising and falling edges. The displacement voltage hysteresis loop characteristic parameters include the maximum displacement amplitude, the rising response time constant, and the falling response time constant. The displacement voltage hysteresis loop characteristic parameters are fitted to the Preisach hysteresis mathematical model to generate a piezoelectric crystal hysteresis effect coefficient matrix describing the nonlinear response of the piezoelectric crystal under dynamic driving conditions; the real-time acceleration value of the printhead module and the physical spraying distance between the nozzle and the substrate surface are obtained during the acceleration and deceleration phases; and an analytical model of ink droplet flight time is constructed based on the ink droplet flight motion equation in fluid mechanics. The real-time acceleration value is input into the predicted motion trajectory curve to calculate the vertical vibration component of the nozzle at the current moment; the vertical vibration component is superimposed on the physical jet spacing to generate the dynamic jet spacing; the dynamic jet spacing is substituted into the ink droplet flight time analytical model to calculate the basic flight time of the ink droplet under the current acceleration condition. The rise and fall response time constants in the piezoelectric crystal hysteresis effect coefficient matrix are convolved with the basic flight time to construct the printhead droplet composite response time model. Based on the voltage change direction and voltage change amplitude corresponding to the printhead drive waveform at the current moment, the corresponding comprehensive response delay time is retrieved from the printhead droplet composite response time model. The nominal response time of the printhead under static calibration conditions is subtracted from the comprehensive response delay time to calculate the actual landing point time offset caused by the combined effect of piezoelectric hysteresis and printhead vibration. Input the actual landing point time offset into the predicted motion trajectory curve, and query the displacement increment of the printhead in the X-axis scanning direction within the time offset interval; at the same time, based on the instantaneous velocity vector of the printhead during the acceleration and deceleration phase and the vertical vibration component, calculate the lateral offset component and longitudinal offset component of the ink droplet during flight due to the coupling effect of the horizontal movement and vertical vibration of the printhead. The displacement increment, lateral offset component, and longitudinal offset component are vector-superimposed to generate the actual landing point spatial offset vector of the ink droplet relative to the nozzle center position; the actual landing point time offset and the actual landing point spatial offset vector are encapsulated into an ink droplet landing point spatiotemporal offset pair; the ink droplet landing point spatiotemporal offset pair is output to the spatiotemporal synchronization processor and matrix-added with the dynamic deviation tensor to generate a full-element dynamic deviation tensor that simultaneously includes nozzle motion deviation, piezoelectric hysteresis deviation, and ink droplet flight deviation.

[0011] In one alternative approach, generating an adaptive dynamic scan path for the current scan strip, based on the dynamic deviation tensor, the actual landing point spatial offset, the nozzle's maximum ignition frequency limit, and crosstalk suppression parameters between nozzles, further includes: Spatiotemporal deviation fusion is performed based on the dynamic deviation tensor of all elements and the spatial offset vector of the actual landing point. The deviation values ​​of all discrete executable printing units within the scan strip are fitted to a surface using the Kriging interpolation algorithm to reconstruct a continuous spatiotemporal deviation field distribution map covering the entire scan strip. The continuous spatiotemporal deviation field distribution map is divided into grids according to the width of a single nozzle scan, and a row deviation correction matrix is ​​generated for each scan line. The row deviation correction matrix contains a sequence of correction weight coefficients that are equally spaced along the X-axis. Based on the maximum ignition frequency limit, minimum ignition interval time, and instantaneous velocity sequence specified in the printhead datasheet, the minimum jettable physical spacing of the printhead in the X-axis direction at the current scanning speed is calculated. The minimum jettable physical spacing is compared with the pixel physical width of the ignition pulse density map to generate the jet density limit factor for each region within the scan strip. For high-density printing areas where the pixel physical width is smaller than the minimum jettable physical spacing, an empty travel skip node is automatically inserted based on the jet density limit factor to ensure that the actual ignition frequency of the printhead is always lower than the maximum ignition frequency limit, thus avoiding nozzle fatigue and ink droplet satellite phenomenon caused by excessive frequency. Extract the nozzle crosstalk coupling matrix calibrated by the printhead manufacturer, wherein the nozzle crosstalk coupling matrix includes the droplet volume deviation and flight direction deviation caused by acoustic resonance and flow channel mutual interference when adjacent nozzles are ignited simultaneously; input the ignition pulse density map slice corresponding to the current scan line into the crosstalk suppression preprocessor and perform convolution operation with the nozzle crosstalk coupling matrix to predict the actual droplet output state of each nozzle when ignited simultaneously; Based on the actual ink droplet output state, the gray level values ​​in the ignition pulse density map are deconvolutionally compensated and corrected to generate an optimized ignition sequence that suppresses crosstalk effects. At the same time, for high-density nozzle combinations that must be ignited simultaneously, a microsecond-level phase delay is inserted to distribute the concentrated ignition energy evenly on the time axis and avoid instantaneous power overload. The line deviation correction matrix, minimum injectable physical spacing, and optimized ignition sequence are input into the path dynamic planner. Based on the movement stage of the printhead within the scanning strip, the scanning strip is divided into three functional areas: acceleration compensation, constant speed precision printing, and deceleration buffer. In the acceleration compensation section, a pre-jet compensation coordinate table is generated to compensate for the effects of speed fluctuations in advance, based on the real-time acceleration value and the feedforward correction term in the line deviation correction matrix. In the constant speed precision printing section, a main jet timing table that precisely matches the target coordinates is generated based on the optimized ignition sequence and the steady-state correction term in the line deviation correction matrix. In the deceleration buffer section, a residual ink management instruction set is generated to recover excess ink droplets and smoothly stop the printhead, based on the remaining deviation energy and printhead inertia parameters. The absolute coordinates of the nozzle at the end of the current scanning strip and the absolute coordinates of the beginning of the next scanning strip are obtained, and the reversing span during strip switching is calculated. The reversing span, the mass inertia parameters of the nozzle module, and the maximum acceleration limit of the linear motor are input into the trajectory smoothing optimizer to generate S-shaped acceleration and deceleration curve parameters connecting the two scanning strips. The S-shaped acceleration and deceleration curve parameters include acceleration limit value, maximum speed inflection point, and backlash compensation amount. The backlash compensation amount is superimposed on the area near the reversing point of the line deviation correction matrix to generate a micro-motion backlash correction pulse for eliminating mechanical transmission backlash. The pre-jet compensation coordinate table, main jet timing table, residual ink management instruction set, S-shaped acceleration / deceleration curve parameters, and micro-motion hysteresis correction pulse are encapsulated to generate an adaptive dynamic scanning path data packet including a timestamp sequence, position coordinate sequence, and ignition control word. The adaptive dynamic scanning path data packet is output to the waveform generation unit to ensure that each nozzle can complete ink droplet ejection at a precise spatiotemporal coordinate point during high-speed reciprocating motion of the printhead, thereby eliminating streaks and splicing misalignments.

[0012] In one alternative approach, determining the overlapping coverage area and feathering transition width between scanning strips based on the splicing error compensation value between adjacent nozzles and the physical width of the nozzles further includes: A standard quartz grating plate is installed on the printing platform as a calibration reference to control the sequential movement of each printhead module to the calibration position. A microscopic vision camera mounted on the printhead bracket acquires the projected images of the nozzle arrays of each printhead on the standard quartz grating plate. Subpixel-level edge extraction is performed on the projected images, and the actual installation coordinates of each printhead relative to the platform coordinate origin are calculated. The actual installation coordinates include X-axis offset, Y-axis offset, and rotation angle deviation. The actual installation coordinates of each printhead are then differentially analyzed with their theoretical design coordinates to generate a multi-printhead installation deviation matrix describing the relative positional relationship between the printheads. This multi-printhead installation deviation matrix includes the horizontal splicing deviation of adjacent printheads in the X-axis direction, the vertical alignment deviation in the Y-axis direction, and the angular torsional deviation around the Z-axis. The multi-nozzle installation deviation matrix is ​​input into the rigid body kinematics model. Combined with the instantaneous velocity vector and real-time acceleration value of the nozzle during the acceleration and deceleration phases, the dynamic deformation of the nozzle caused by inertial force and centrifugal force during high-speed reciprocating motion is calculated. The dynamic deformation is superimposed on the multi-nozzle installation deviation matrix to generate a dynamic splicing error compensation value sequence that changes in real time with the nozzle motion state. The dynamic splicing error compensation value sequence includes time-varying compensation coefficients that are equally spaced along the X-axis direction of the scanning strip. Obtain the physical width W of the nozzle and the theoretical spacing D between adjacent nozzles. Combine the maximum positive deviation and the maximum negative deviation in the dynamic splicing error compensation value sequence to calculate the effective coverage width between the scanning strips of adjacent nozzles. Multiply the basic overlap width by the safety redundancy coefficient to generate the final determined overlap coverage area width value. This ensures that there is always physical overlap between the scanning strips of adjacent nozzles under different movement speeds and acceleration conditions, avoiding gaps caused by dynamic deviations. The width value of the overlapping coverage area is input into the feathering parameter optimizer, and the optimal feathering transition width matching the current image content is calculated by combining the image texture features in the overlapping area of ​​the ignition pulse density map. The width of the overlapping coverage area and the optimal feathering transition width are encapsulated into a splicing compensation parameter set. This splicing compensation parameter set is output to the scanning strip division module as a boundary constraint condition when dividing parallel scanning strips. The splicing compensation parameter set is transmitted to the path dynamic planner. When generating an adaptive dynamic scanning path, the ignition timing of the overlapping coverage area is coordinated and scheduled by two printheads to ensure that the two printheads eject ink droplets sequentially or simultaneously at the same physical position according to the assigned weight coefficient, thereby achieving sub-pixel-level seamless fusion of the splicing area.

[0013] According to another aspect of the present invention, a reciprocating high-speed inkjet printing path optimization device based on spatiotemporal synchronization control is provided, comprising: The strip planning module is used to generate an ignition pulse density map corresponding to each nozzle based on the CIP4 digital workflow file of the image to be printed. Each pixel in the ignition pulse density map includes an absolute coordinate vector, a gray level value, and a channel identifier. Based on the linear array layout of the nozzles on the printhead chassis, the staggered offset of the printhead module, and the ignition pulse density map, the module calculates the starting absolute coordinates, ending absolute coordinates, the dwell time threshold of the printhead when the strip changes direction, the overlapping coverage area between the scan strips, and the feathering transition width for each scanning strip. The motion prediction and spatiotemporal deviation calculation module is used to input real-time position coordinates, instantaneous velocity, instantaneous acceleration, mass inertia parameters of the printhead module, and thrust fluctuation coefficient of the linear motor into the motion trajectory predictor to predict the printhead's motion trajectory curve over multiple sampling periods. It inputs the starting absolute coordinates, ending absolute coordinates, printhead dwell-cooling time threshold during strip reversal, overlapping coverage area between scan strips, feathering transition width, and predicted motion trajectory curve of each scan strip into the spatiotemporal synchronization processor to construct the dynamic deviation tensor between the target spatial coordinates of all executable printing units within the current scan strip and the predicted arrival position of the printhead. Based on the time-of-flight compensation model of ink droplets during the ejection process and the piezoelectric crystal hysteresis coefficient of the printhead during acceleration and deceleration, it calculates the actual landing point time offset and actual landing point spatial offset of the ink droplets from the nozzle to the substrate surface. The dynamic path planning and waveform generation module generates an adaptive dynamic scanning path for the current scan strip based on the dynamic deviation tensor, actual landing point spatial offset, printhead maximum firing frequency limit, and crosstalk suppression parameters between nozzles. This path eliminates streak defects caused by printhead speed fluctuations and splicing misalignment caused by mechanical backlash. The adaptive dynamic scanning path and the grayscale level value of each executable printing unit are input to the waveform generation unit to generate a gradient firing waveform signal adapted to the piezoelectric printhead. The gradient firing waveform signal is then temperature-compensated and corrected based on the real-time temperature value fed back by the printhead temperature sensor to ensure the consistency of ink droplet volume and velocity at different temperatures. The printing execution and feedback module transmits the gradient ignition waveform signal to the FPGA logic unit of the printhead control board via a high-speed serial interface. The FPGA logic unit triggers the ignition operation of the corresponding nozzle at the precise spatiotemporal coordinate point after dynamic deviation tensor correction, based on the timing nodes planned by the adaptive dynamic scanning path, to complete the printing task of the current scan strip. The module also uses the feedback voltage signal of the nozzle to determine whether there is a blocked or abnormal nozzle and updates the nozzle status data to the ignition pulse density map in real time, performing neighboring nozzle compensation printing for abnormal nozzles.

[0014] According to another aspect of the present invention, a computing device is provided, comprising: a processor, a memory, a communication interface, and a communication bus, wherein the processor, the memory, and the communication interface communicate with each other via the communication bus; The memory is used to store at least one executable instruction, which causes the processor to perform the operation corresponding to the above-described reciprocating high-speed inkjet printing path optimization method based on spatiotemporal synchronization control.

[0015] According to the solution provided by the present invention, an ignition pulse density map corresponding to each nozzle is generated based on the CIP4 digital workflow file of the image to be printed. Each pixel in the ignition pulse density map includes an absolute coordinate vector, a grayscale level value, and a channel identifier. Based on the linear array layout of the nozzles on the printhead chassis, the staggered offset of the printhead module, and the ignition pulse density map, the starting absolute coordinates, ending absolute coordinates, the dwell time threshold of the printhead during strip reversal, the overlapping coverage area between scan strips, and the feathering transition width are calculated for each scan strip. Real-time position coordinates, instantaneous velocity, instantaneous acceleration, the mass inertia parameters of the printhead module, and the thrust fluctuation coefficient of the linear motor are input to the motion trajectory predictor to predict the predicted motion trajectory curve of the printhead over multiple future sampling periods. The starting absolute coordinates, ending absolute coordinates, the dwell time threshold of the printhead during strip reversal, the overlapping coverage area between scan strips, the feathering transition width, and the predicted motion trajectory curve for each scan strip are input. The system uses a spatiotemporal synchronization processor to construct a dynamic deviation tensor between the target spatial coordinates of all executable printing units within the current scan strip and the predicted arrival position of the printhead. Based on the droplet flight time compensation model during the ejection process and the piezoelectric crystal hysteresis coefficient during the printhead's acceleration and deceleration phases, it calculates the actual landing time offset and actual landing spatial offset of the droplets from the nozzle to the substrate surface. Based on the dynamic deviation tensor, actual landing spatial offset, the printhead's maximum firing frequency limit, and crosstalk suppression parameters between nozzles, it generates an adaptive dynamic scanning path for the current scan strip to eliminate streak defects caused by printhead speed fluctuations and splicing misalignments caused by mechanical backlash. The adaptive dynamic scanning path and the grayscale value of each executable printing unit are input to a waveform generation unit to generate a gradient firing waveform signal adapted to the piezoelectric printhead. The gradient firing waveform signal is then temperature-compensated and corrected based on the real-time temperature value fed back from the printhead temperature sensor to ensure droplet volume and velocity consistency at different temperatures. The gradient ignition waveform signal is transmitted to the FPGA logic unit of the printhead control board via a high-speed serial interface. The FPGA logic unit, based on the timing nodes planned by the adaptive dynamic scanning path, triggers the ignition operation of the corresponding nozzle at the precise spatiotemporal coordinate point after dynamic deviation tensor correction, completing the printing task of the current scan strip. The feedback voltage signal from the nozzle determines whether there are blocked or abnormal nozzles, and the nozzle status data is updated in real-time to the ignition pulse density map. Abnormal nozzles are compensated by printing with adjacent nozzles. This invention dynamically divides the printing process into three segments based on real-time motion: accelerated pre-spraying, uniform speed fine printing, and deceleration recovery, embedding an S-shaped reversal curve and micro-motion hysteresis compensation. This effectively improves the printing stroke utilization rate while eliminating streaks and splicing misalignment. The overlapping area is calculated in real-time based on multi-nozzle installation deviations and motion deformation, and the feathering width is optimized by combining image texture features to achieve seamless splicing at high speeds, avoiding white gaps or overexposure.

[0016] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0017] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This diagram illustrates a flow chart of a reciprocating high-speed inkjet printing path optimization method based on spatiotemporal synchronization control, according to an embodiment of the present invention. Figure 1 ; Figure 2 This diagram illustrates a flow chart of a reciprocating high-speed inkjet printing path optimization method based on spatiotemporal synchronization control, according to an embodiment of the present invention. Figure 2 ; Figures 3a to 3c A schematic diagram of adaptive dynamic scanning path planning according to an embodiment of the present invention is shown; Figure 4 A schematic diagram of the framework of a reciprocating high-speed inkjet printing path optimization device based on spatiotemporal synchronization control according to an embodiment of the present invention is shown. Figure 5 A schematic diagram of the structure of a computing device according to an embodiment of the present invention is shown. Detailed Implementation

[0018] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0019] Figure 1 , Figure 2 A flowchart illustrating the reciprocating high-speed inkjet printing path optimization method based on spatiotemporal synchronization control according to an embodiment of the present invention is shown. Specifically, as... Figure 1 , Figure 2 As shown, it includes the following steps: Step S101: Generate an ignition pulse density map corresponding to each nozzle based on the CIP4 digital workflow file of the image to be printed. Each pixel in the ignition pulse density map includes an absolute coordinate vector, a gray level value, and a channel identifier. Based on the linear array layout of the nozzles on the printhead chassis, the staggered offset of the printhead module, and the ignition pulse density map, calculate the starting absolute coordinates, ending absolute coordinates, the dwell time threshold of the printhead when the strip changes direction, the overlapping coverage area between the scan strips, and the feathering transition width for each scanning strip.

[0020] In this embodiment, an ignition pulse density map containing absolute coordinates, grayscale, and channel information is directly generated by parsing the CIP4 digital workflow file. This ensures that the image information in the digital file can be unambiguously converted into ignition commands for each nozzle of the printhead, avoiding image distortion or positional shifts caused by coordinate transformation or format parsing, thus guaranteeing printing accuracy from the source. By accurately calculating the linear array layout of the printhead chassis and the staggered arrangement offset of the modules, and using this as a basis for dividing the scanning stripes, systematic errors caused by printhead manufacturing tolerances or installation position deviations can be effectively compensated, allowing for smooth transitions between different printhead modules and fundamentally reducing regular stripes caused by physical structure. By calculating the start / end coordinates of each scanning strip, precise boundaries are provided for path planning. At the same time, the set dwell cooling time threshold can prevent the printhead from overheating due to continuous high-speed reciprocating motion and avoid unnecessary waiting time. The overlapping coverage area and feathering transition width are eliminated by algorithmic fusion without sacrificing too much printing speed, achieving the best balance between efficiency and quality. By using grayscale levels as the core element of the ignition pulse density map, the printing path can be differentiated based on the density variations of the image content. Combined with striping and feathering parameters, different printing strategies can be intelligently applied to areas with rich image detail and gradient areas, significantly improving the printing system's adaptability to complex images. For example, consider printing a wide-format landscape poster containing a gradient blue sky and red advertising text. After parsing the CIP4 file, for the sky area, the pixels in the ignition pulse density map have lower grayscale levels (e.g., 20%) and a "channel identifier = cyan"; while for the text edges, the pixels have extremely high grayscale levels (e.g., 100%) and a "channel identifier = magenta". Each pixel is accompanied by its absolute coordinates on the printing medium, such as (100mm, 50mm). Assuming the physical width of the printhead is 50mm, but the actual coverage width is only 45mm due to staggered arrangement, the entire 2-meter-wide poster is divided into multiple 45mm-wide scanning strips along the feed direction based on this parameter. When printing the first strip, the printhead needs to start spraying ink from 0mm on the X-axis and stop at 2000mm. Because this strip is long, the printhead will generate heat after continuous high-speed operation. Therefore, the printhead needs to pause for 50 milliseconds to cool down after reaching the 2000mm endpoint before reversing its movement. When printing the first strip (Strip A) and the second strip (Strip B), a 2mm overlap is set. Within this 2mm, the feathering transition width is set to 2mm. At the far left of the overlap area, the inkjet weight of Strip A is 100%, and that of Strip B is 0%; in the middle of the overlap area, they each occupy 50%; at the far right of the overlap area, Strip A is 0%, and that of Strip B is 100%. Thus, the gradient blue of the sky can transition seamlessly from Strip A to Strip B without a noticeable dividing line.

[0021] In one alternative approach, generating an ignition pulse density map for each nozzle based on a CIP4 digital workflow file of the image to be printed further includes: Obtain the CIP4 digital workflow file of the image to be printed, and parse the CIP4 digital workflow file using a RIP raster image processor to generate a digital matrix of printing areas including the four CMYK color channels; The digital matrix of the printing area is matched with the physical resolution parameters of the nozzle to generate an ignition pulse density map corresponding to each nozzle.

[0022] In this embodiment, a standard CIP4 digital workflow file is used and parsed by a RIP raster image processor to ensure that the standard file format of the printing industry can be accurately interpreted, guaranteeing the accuracy of the printed output from the source of data processing. The parsed CMYK four-color channel digital matrix is ​​matched with the physical resolution of the printhead to directly generate an ignition pulse density map corresponding to each nozzle. This allows each tiny nozzle to work independently according to its precise position and color task in the image, significantly improving the fineness and detail of the print. Since the generated pulse density map explicitly contains the CMYK four-color channel identifiers, combined with absolute coordinate vectors, it ensures that ink droplets of different colors land precisely at the positions defined in the digital file. This is crucial for printing color images requiring high-precision color reproduction and effectively eliminates color misregistration problems caused by different color channel processing paths. Simultaneously, through RIP parsing and resolution matching, it can automatically adapt to printheads of different resolutions (e.g., 600dpi, 1200dpi) without manual intervention, improving production efficiency and equipment versatility. For example, printing a color brochure containing a company logo and QR code. For the logo area, RIP resolves a vibrant red. In the generated CMYK matrix, pixels in the magenta (M) and yellow (Y) channels are assigned higher grayscale values, while the cyan (C) and black (K) channels have zero grayscale values. For the QR code area, RIP resolves it to consist of black and white. In the matrix, for the black lines of the QR code, all four channels are set to a specific combination of colors to synthesize black, or primarily high grayscale values ​​are found in the K (black) channel; for the white background, all channels have zero grayscale values. Assuming the flyer's design resolution is 600 dpi, and the printhead's physical resolution is also 600 dpi, a match is detected, allowing for direct 1:1 pixel mapping without resampling, ensuring no loss of image detail (especially the fine lines of the QR code). After resolution matching, tasks are assigned to each printhead. Assuming the 100th nozzle in the printhead array, based on its physical location, corresponds to a pixel at coordinates (X=50mm, Y=20mm) in the digital matrix, which happens to be within the red area of ​​the logo. The ignition pulse density map data entries generated for this nozzle are: absolute coordinate vector (50mm, 20mm), grayscale level values ​​(M: 80%, Y: 70%, C: 0%, K: 0%), and channel identifier (M, Y). This means that when the printhead moves to the absolute position (50mm, 20mm) on the platform, the nozzle needs to eject magenta and yellow ink droplets based on 80% and 70% grayscale values, mixing them to form red.Suppose that nozzle number 200 corresponds to a pixel at coordinates (X=120mm, Y=35mm) in the digital matrix. This pixel is located on the black line of the QR code. The generated data entries are: absolute coordinate vector (120mm, 35mm), grayscale level value (K: 90%), and channel identifier (K). The nozzle corresponding to the background area of ​​the QR code might generate a grayscale level value of 0, meaning "no firing" at that coordinate point. Through this method, the abstract CIP4 digital file is precisely converted into specific instructions guiding each nozzle on when, where, what color, and how much ink to spray.

[0023] In one alternative approach, calculating the starting absolute coordinates, ending absolute coordinates, nozzle dwell-cooling time threshold during strip reversal, overlapping coverage area between scan strips, and feathering transition width for each scan strip further includes: Based on the linear array layout of the nozzles on the nozzle chassis, the staggered offset of the nozzle modules, and the ignition pulse density map, the printing area is divided into several parallel scanning strips along the media feed direction. Assign a strip index number to each scan strip and calculate the starting absolute coordinates, ending absolute coordinates, and the dwell time threshold of the nozzle when the strip changes direction for each scan strip; The overlapping coverage area and feathering transition width between scanning strips are determined based on the splicing error compensation value between the physical width of the nozzle and adjacent nozzles.

[0024] In this embodiment, the scanning strips are segmented according to the linear array layout of the nozzles and the staggered arrangement of the modules, ensuring that each scan of the printhead covers the maximum effective printing width and reducing unnecessary idle travel. Simultaneously, a dwell-cooling time threshold is independently calculated for each strip to avoid efficiency waste caused by a globally uniform wait, maximizing the frequency of reciprocating scans while ensuring printhead safety. The splicing error compensation value dynamically compensates for actual physical errors such as minor angular deviations and horizontal offsets during printhead installation, fundamentally eliminating white gaps or indentations between strips caused by hardware inconsistencies, ensuring continuous and complete graphics printed by multi-printhead splicing. A feathered transition width is introduced within the overlapping coverage area, allowing the ink volume of adjacent strips to gradually change according to a specific weighted curve at the splicing point, rather than abruptly connecting. This conceals splicing marks that may be caused by minor fluctuations in mechanical movement or slight deviations in ink droplet placement, making the printed image, especially in large color blocks and gradient areas, appear seamless. By calculating an independent dwell-cooling time threshold for each strip, the pause time during reversal can be determined based on the strip length and the printhead's workload (jetting frequency) on that strip. After printing long strips or high-density prints, the pause time is extended accordingly to ensure sufficient heat dissipation; after printing short strips or low-density prints, the pause time is shortened to increase speed and prevent printhead overheating that could lead to decreased print quality or damage.

[0025] In one alternative approach, determining the overlapping coverage area and feathering transition width between scanning strips based on the splicing error compensation value between adjacent nozzles and the physical width of the nozzles further includes: A standard quartz grating plate is installed on the printing platform as a calibration reference to control the sequential movement of each printhead module to the calibration position. A microscopic vision camera mounted on the printhead bracket acquires the projected images of the nozzle arrays of each printhead on the standard quartz grating plate. Subpixel-level edge extraction is performed on the projected images, and the actual installation coordinates of each printhead relative to the platform coordinate origin are calculated. The actual installation coordinates include X-axis offset, Y-axis offset, and rotation angle deviation. The actual installation coordinates of each printhead are then differentially analyzed with their theoretical design coordinates to generate a multi-printhead installation deviation matrix describing the relative positional relationship between the printheads. This multi-printhead installation deviation matrix includes the horizontal splicing deviation of adjacent printheads in the X-axis direction, the vertical alignment deviation in the Y-axis direction, and the angular torsional deviation around the Z-axis. The multi-nozzle installation deviation matrix is ​​input into the rigid body kinematics model. Combined with the instantaneous velocity vector and real-time acceleration value of the nozzle during the acceleration and deceleration phases, the dynamic deformation of the nozzle caused by inertial force and centrifugal force during high-speed reciprocating motion is calculated. The dynamic deformation is superimposed on the multi-nozzle installation deviation matrix to generate a dynamic splicing error compensation value sequence that changes in real time with the nozzle motion state. The dynamic splicing error compensation value sequence includes time-varying compensation coefficients that are equally spaced along the X-axis direction of the scanning strip. Obtain the physical width W of the nozzle and the theoretical spacing D between adjacent nozzles. Combine the maximum positive deviation and the maximum negative deviation in the dynamic splicing error compensation value sequence to calculate the effective coverage width between the scanning strips of adjacent nozzles. Multiply the basic overlap width by the safety redundancy coefficient to generate the final determined overlap coverage area width value. This ensures that there is always physical overlap between the scanning strips of adjacent nozzles under different movement speeds and acceleration conditions, avoiding gaps caused by dynamic deviations. The width value of the overlapping coverage area is input into the feathering parameter optimizer, and the optimal feathering transition width matching the current image content is calculated by combining the image texture features in the overlapping area of ​​the ignition pulse density map. The width of the overlapping coverage area and the optimal feathering transition width are encapsulated into a splicing compensation parameter set. This splicing compensation parameter set is output to the scanning strip division module as a boundary constraint condition when dividing parallel scanning strips. The splicing compensation parameter set is transmitted to the path dynamic planner. When generating an adaptive dynamic scanning path, the ignition timing of the overlapping coverage area is coordinated and scheduled by two printheads to ensure that the two printheads eject ink droplets sequentially or simultaneously at the same physical position according to the assigned weight coefficient, thereby achieving sub-pixel-level seamless fusion of the splicing area.

[0026] In this embodiment, a standard quartz grating plate is used as a high-precision reference, combined with a microscopic vision camera for sub-pixel-level edge extraction. This improves the accuracy of the printhead's actual installation position detection to the micrometer or even sub-micrometer level, capturing minute installation deviations (including translation and rotation) that are imperceptible to the naked eye and traditional methods. The inertial force and centrifugal force generated by the printhead's acceleration and deceleration during high-speed reciprocating motion are calculated using a rigid body kinematics model. The compensation value is adjusted in real time according to changes in the printhead's speed and acceleration, solving the problem of dynamic splicing misalignment caused by mechanical vibration and deformation during high-speed printing. By analyzing the maximum positive and negative deviations in the dynamic splicing error sequence, the width of the overlapping coverage area is determined. Regardless of the printhead's speed and acceleration state during scanning, physical overlap between the strips printed by adjacent printheads is always ensured, fundamentally eliminating gaps caused by unexpected dynamic deviations and improving print yield. For example, a large-format inkjet printer equipped with two CMYK printhead modules is used to print outdoor advertising posters. Due to manufacturing tolerances and assembly errors, the two sets of printheads have a vertical misalignment of approximately ±15 micrometers in the Y direction, and an additional ±8 micrometers of dynamic offset due to inertia during high-speed scanning (2 m / s) reversal. If designed with a fixed 100-micrometer overlap, fine white lines may appear at high speeds due to the dynamic offset exceeding the overlap range, especially noticeable against light-colored backgrounds. The static deviation was calibrated to +12μm (Y direction) using a quartz grating and a microscope camera; combined with the motion state, the rigid body model predicted a peak dynamic offset of +9μm; the total maximum deviation was calculated to be 21μm, the basic overlap was set to 42μm, and then multiplied by a safety factor of 1.3, resulting in a final 55μm overlap coverage; within the overlap area, if the image content is a gradient of blue sky, a 30μm wide feathering is used; if it is the edge of text, a 10μm narrow feathering is used to maintain sharpness; during printing, the left and right printheads distribute ink droplets in the overlap area in a 7:3 or 5:5 ratio and the ignition timing is precisely synchronized by the FPGA. Regardless of whether the poster is produced in low-speed fine mode or high-speed production mode, there are no visible seams, color breaks, or exposed white areas at the splicing points.

[0027] Step S102: Input the real-time position coordinates, instantaneous velocity, instantaneous acceleration, mass inertia parameters of the printhead module, and thrust fluctuation coefficient of the linear motor into the motion trajectory predictor to predict the printhead's predicted motion trajectory curve over multiple future sampling periods; input the starting absolute coordinates, ending absolute coordinates, printhead dwell cooling time threshold during strip reversal, overlapping coverage area between scan strips, feathering transition width, and predicted motion trajectory curve of each scan strip into the spatiotemporal synchronization processor to construct the dynamic deviation tensor between the target spatial coordinates of all executable printing units within the current scan strip and the predicted arrival position of the printhead; calculate the actual landing time offset and actual landing spatial offset of the ink droplet from the nozzle to the substrate surface based on the ink droplet flight time compensation model during the ejection process and the piezoelectric crystal hysteresis effect coefficient of the printhead during acceleration and deceleration.

[0028] In this embodiment, the target spatial coordinates are correlated with the predicted arrival position using a dynamic deviation tensor, solving the spatiotemporal coupling problem of "when to spray" and "where to spray" in high-speed printing. This enables the control system to accurately determine the timing and predicted position of the printhead to trigger ignition at the target coordinate landing point, achieving true spatiotemporal synchronous control. By calculating the combined offset caused by speed fluctuations, piezoelectric hysteresis, and droplet flight, the printhead can accurately deliver the droplets to the target position even during acceleration and deceleration phases with constantly changing acceleration. This expands the high-quality printing area from the traditional constant-speed phase to the entire scanning stroke, significantly improving the overall efficiency and accuracy of reciprocating printing.

[0029] In one alternative approach, the predicted motion trajectory curves of the nozzle over multiple future sampling periods further include: The orthogonal coded pulse signal output by the grating ruler feedback system is acquired in real time. The orthogonal coded pulse signal is subjected to a fourth frequency harmonic processing by the motion controller to calculate the real-time position coordinates, instantaneous motion velocity and instantaneous acceleration of the nozzle module in the X-axis scanning direction. The real-time position coordinates, instantaneous velocity, instantaneous acceleration, mass inertia parameters of the nozzle module, and thrust fluctuation coefficient of the linear motor are input into the motion trajectory predictor to predict the motion trajectory curve of the nozzle in multiple future sampling periods. The predicted motion trajectory curve includes the predicted position sequence, predicted velocity sequence, and predicted acceleration sequence corresponding to the timestamp.

[0030] In this embodiment, by performing quadruple frequency harmonic processing on the orthogonal encoded pulse signal of the grating ruler, the original position detection accuracy is improved by four times, enabling the detection of extremely minute displacement changes. The mass inertia parameter of the printhead module (describing the magnitude of inertia) and the thrust fluctuation coefficient of the linear motor (describing the unevenness of output force) significantly improve the accuracy of the motion trajectory predictor. By accurately predicting the motion trajectory over multiple future sampling periods, the dynamic deviations that will occur can be calculated in advance and feedforward compensation can be performed accordingly, rather than performing delayed feedback correction after the deviation occurs. This fundamentally solves the control lag problem caused by feedback delay in high-speed motion and significantly improves the dynamic accuracy of printing.

[0031] In one alternative approach, the calculation of the actual landing point time offset and actual landing point spatial offset of the ink droplet from the nozzle to the substrate surface, based on the time-of-flight compensation model of the ink droplet during the ejection process and the piezoelectric crystal hysteresis coefficient of the printhead during the acceleration and deceleration phases, further includes: With the nozzle module stationary, a set of stepped scanning voltage signals covering the entire voltage range are applied to the test nozzle of the piezoelectric nozzle. The mechanical displacement response curves of the piezoelectric crystal under different voltage excitations are collected by a laser Doppler vibration meter installed below the nozzle. The mechanical displacement response curves are differentiated to extract the displacement voltage hysteresis loop characteristic parameters of the piezoelectric crystal at the rising and falling edges. The displacement voltage hysteresis loop characteristic parameters include the maximum displacement amplitude, the rising response time constant, and the falling response time constant. The displacement voltage hysteresis loop characteristic parameters are fitted to the Preisach hysteresis mathematical model to generate a piezoelectric crystal hysteresis effect coefficient matrix describing the nonlinear response of the piezoelectric crystal under dynamic driving conditions; the real-time acceleration value of the printhead module and the physical spraying distance between the nozzle and the substrate surface are obtained during the acceleration and deceleration phases; and an analytical model of ink droplet flight time is constructed based on the ink droplet flight motion equation in fluid mechanics. The real-time acceleration value is input into the predicted motion trajectory curve to calculate the vertical vibration component of the nozzle at the current moment; the vertical vibration component is superimposed on the physical jet spacing to generate the dynamic jet spacing; the dynamic jet spacing is substituted into the ink droplet flight time analytical model to calculate the basic flight time of the ink droplet under the current acceleration condition. The rise and fall response time constants in the piezoelectric crystal hysteresis effect coefficient matrix are convolved with the basic flight time to construct the printhead droplet composite response time model. Based on the voltage change direction and voltage change amplitude corresponding to the printhead drive waveform at the current moment, the corresponding comprehensive response delay time is retrieved from the printhead droplet composite response time model. The nominal response time of the printhead under static calibration conditions is subtracted from the comprehensive response delay time to calculate the actual landing point time offset caused by the combined effect of piezoelectric hysteresis and printhead vibration. Input the actual landing point time offset into the predicted motion trajectory curve, and query the displacement increment of the printhead in the X-axis scanning direction within the time offset interval; at the same time, based on the instantaneous velocity vector of the printhead during the acceleration and deceleration phase and the vertical vibration component, calculate the lateral offset component and longitudinal offset component of the ink droplet during flight due to the coupling effect of the horizontal movement and vertical vibration of the printhead. The displacement increment, lateral offset component, and longitudinal offset component are vector-superimposed to generate the actual landing point spatial offset vector of the ink droplet relative to the nozzle center position; the actual landing point time offset and the actual landing point spatial offset vector are encapsulated into an ink droplet landing point spatiotemporal offset pair; the ink droplet landing point spatiotemporal offset pair is output to the spatiotemporal synchronization processor and matrix-added with the dynamic deviation tensor to generate a full-element dynamic deviation tensor that simultaneously includes nozzle motion deviation, piezoelectric hysteresis deviation, and ink droplet flight deviation.

[0032] In this embodiment, a laser Doppler vibrometer is used to accurately measure the displacement response of the piezoelectric crystal across the entire voltage range and extract the hysteresis loop characteristic parameters of the rising / falling edges. These parameters are then fitted into a Preisach mathematical model, which accurately describes the inherent nonlinear hysteresis characteristics of the piezoelectric material. By mapping the actual landing point time offset back to the predicted motion trajectory, the nozzle displacement increment is queried, and the lateral / longitudinal offset components are calculated by combining the coupling effect of horizontal and vertical motion. Finally, a droplet landing point spatiotemporal offset pair containing both time and spatial offsets is generated. The offset pair is then matrix-added with the dynamic deviation tensor to obtain a full-element dynamic deviation tensor that simultaneously covers motion deviation, piezoelectric hysteresis deviation, and droplet flight deviation. This achieves a comprehensive characterization of all major error sources in the printing process, enabling precise correction of the ignition command in both the time and spatial dimensions. This ensures that the droplet accurately hits the target coordinates even under high-speed, dynamically changing conditions.

[0033] Step S103: Based on the dynamic deviation tensor, actual landing point spatial offset, printhead maximum firing frequency limit, and crosstalk suppression parameters between nozzles, an adaptive dynamic scanning path is generated for the current scanning strip to eliminate streak defects caused by printhead speed fluctuations and splicing misalignment caused by mechanical backlash. The adaptive dynamic scanning path and the grayscale level value of each executable printing unit are input to the waveform generation unit to generate a gradient firing waveform signal adapted to the piezoelectric printhead. The gradient firing waveform signal is temperature compensated and corrected based on the real-time temperature value fed back by the printhead temperature sensor to ensure the volume and velocity consistency of ink droplets at different temperatures.

[0034] In this embodiment, the dynamic deviation tensor (containing velocity fluctuation information) and the actual droplet spatial offset are integrated into the path planning to accurately compensate for droplet droplet offset caused by uneven velocity, thereby eliminating streaks. Simultaneously, targeted compensation for reverse gaps in the path solves the splicing misalignment problem during mechanical reversal. The optimized scanning path is combined with grayscale values ​​to generate a gradient ignition waveform, enabling the drive waveform to dynamically adjust according to the printing position and ink volume requirements. More importantly, temperature sensor feedback is introduced to correct the waveform in real time, overcoming the influence of temperature changes on ink viscosity and piezoelectric effect, ensuring a high degree of consistency in droplet volume and velocity throughout the printing process.

[0035] In one alternative approach, the adaptive dynamic scanning path includes segmented motion control parameters for the pre-spray compensation interval of the printhead in the acceleration phase, the normal spray interval in the constant speed phase, and the residual ink recovery interval in the deceleration phase, as well as S-shaped acceleration / deceleration curve parameters and reverse gap compensation parameters at the reversal points at both ends of the scanning strip. The gradient ignition waveform signal includes voltage amplitude step parameters that control the droplet volume, trigger delay time that controls the droplet ejection phase, and pulse width modulation curve that controls the droplet breakage velocity.

[0036] In this embodiment, for example, when printing pharmaceutical packaging labels, the printhead reciprocates at a speed of 2.5 m / s, and the end of each strip needs to complete the reversal within 2 ms. If a traditional trapezoidal acceleration and deceleration is used, the reversal impact causes mechanical vibration, resulting in burrs on the edges of the QR code; during the initial acceleration phase, ink droplets lag, causing the first few lines of light-colored backgrounds to fade; and during the final deceleration phase, residual ink splashes, causing smudging at the edges of dark blocks. In this application, pre-jet compensation is initiated before the speed reaches 1.8 m / s, with ignition 8 μs in advance to ensure accurate placement of the first line of ink droplets; during the normal jetting interval in the uniform speed phase, the main body of the QR code is printed with standard timing, combined with a gradient waveform (medium droplets + narrow pulse width) to ensure sharp edges without satellite dots; during the last 3 mm of the deceleration phase, the residual ink recovery interval is entered, and the waveform voltage slope decreases to suppress excess ink droplets; the reversal point adopts an S-shaped curve (maximum acceleration ≤ 10). 6 The strip is designed to have a zero offset starting position, with a voltage droplet (3pL) and an 8μm reverse gap compensation. The light-colored area uses a low-voltage droplet (3pL), while the dark-colored area uses a double-pulse large droplet (12pL). The breakage speed is optimized by PWM to avoid splashing.

[0037] In one alternative approach, generating an adaptive dynamic scan path for the current scan strip, based on the dynamic deviation tensor, the actual landing point spatial offset, the nozzle's maximum ignition frequency limit, and crosstalk suppression parameters between nozzles, further includes: Spatiotemporal deviation fusion is performed based on the dynamic deviation tensor of all elements and the spatial offset vector of the actual landing point. The deviation values ​​of all discrete executable printing units within the scan strip are fitted to a surface using the Kriging interpolation algorithm to reconstruct a continuous spatiotemporal deviation field distribution map covering the entire scan strip. The continuous spatiotemporal deviation field distribution map is divided into grids according to the width of a single nozzle scan, and a row deviation correction matrix is ​​generated for each scan line. The row deviation correction matrix contains a sequence of correction weight coefficients that are equally spaced along the X-axis. Based on the maximum ignition frequency limit, minimum ignition interval time, and instantaneous velocity sequence specified in the printhead datasheet, the minimum jettable physical spacing of the printhead in the X-axis direction at the current scanning speed is calculated. The minimum jettable physical spacing is compared with the pixel physical width of the ignition pulse density map to generate the jet density limit factor for each region within the scan strip. For high-density printing areas where the pixel physical width is smaller than the minimum jettable physical spacing, an empty travel skip node is automatically inserted based on the jet density limit factor to ensure that the actual ignition frequency of the printhead is always lower than the maximum ignition frequency limit, thus avoiding nozzle fatigue and ink droplet satellite phenomenon caused by excessive frequency. Extract the nozzle crosstalk coupling matrix calibrated by the printhead manufacturer, wherein the nozzle crosstalk coupling matrix includes the droplet volume deviation and flight direction deviation caused by acoustic resonance and flow channel mutual interference when adjacent nozzles are ignited simultaneously; input the ignition pulse density map slice corresponding to the current scan line into the crosstalk suppression preprocessor and perform convolution operation with the nozzle crosstalk coupling matrix to predict the actual droplet output state of each nozzle when ignited simultaneously; Based on the actual ink droplet output state, the gray level values ​​in the ignition pulse density map are deconvolutionally compensated and corrected to generate an optimized ignition sequence that suppresses crosstalk effects. At the same time, for high-density nozzle combinations that must be ignited simultaneously, a microsecond-level phase delay is inserted to distribute the concentrated ignition energy evenly on the time axis and avoid instantaneous power overload. The line deviation correction matrix, minimum injectable physical spacing, and optimized ignition sequence are input into the path dynamic planner. Based on the movement stage of the printhead within the scanning strip, the scanning strip is divided into three functional areas: acceleration compensation, constant speed precision printing, and deceleration buffer. In the acceleration compensation section, a pre-jet compensation coordinate table is generated to compensate for the effects of speed fluctuations in advance, based on the real-time acceleration value and the feedforward correction term in the line deviation correction matrix. In the constant speed precision printing section, a main jet timing table that precisely matches the target coordinates is generated based on the optimized ignition sequence and the steady-state correction term in the line deviation correction matrix. In the deceleration buffer section, a residual ink management instruction set is generated to recover excess ink droplets and smoothly stop the printhead, based on the remaining deviation energy and printhead inertia parameters. The absolute coordinates of the nozzle at the end of the current scanning strip and the absolute coordinates of the beginning of the next scanning strip are obtained, and the reversing span during strip switching is calculated. The reversing span, the mass inertia parameters of the nozzle module, and the maximum acceleration limit of the linear motor are input into the trajectory smoothing optimizer to generate S-shaped acceleration and deceleration curve parameters connecting the two scanning strips. The S-shaped acceleration and deceleration curve parameters include acceleration limit value, maximum speed inflection point, and backlash compensation amount. The backlash compensation amount is superimposed on the area near the reversing point of the line deviation correction matrix to generate a micro-motion backlash correction pulse for eliminating mechanical transmission backlash. The pre-jet compensation coordinate table, main jet timing table, residual ink management instruction set, S-shaped acceleration / deceleration curve parameters, and micro-motion hysteresis correction pulse are encapsulated to generate an adaptive dynamic scanning path data packet including a timestamp sequence, position coordinate sequence, and ignition control word. The adaptive dynamic scanning path data packet is output to the waveform generation unit to ensure that each nozzle can complete ink droplet ejection at a precise spatiotemporal coordinate point during high-speed reciprocating motion of the printhead, thereby eliminating streaks and splicing misalignments.

[0038] In this embodiment, the deviation values ​​of discrete executable printing units are fitted into a continuous spatiotemporal deviation field distribution map using the Kriging interpolation algorithm. This transforms compensation from a point-to-point correction of isolated locations to a continuous surface compensation covering the entire scan strip. This eliminates compensation gaps that may result from the discretization of deviation data, ensuring accurate deviation correction for every location within the printing area. High-density printing areas are automatically identified and processed by calculating the minimum jettable physical spacing in real time and comparing it with the image pixel width. When the image density exceeds the printhead's physical limit, an empty travel skip node is automatically inserted, ensuring the printhead always operates within a safe frequency range and preventing reliability issues such as nozzle fatigue and droplet satellite points caused by excessively high frequencies. Figures 3a to 3cAs shown, a high-precision circuit board is printed, with one area having extremely high line density, where printing needs to begin in the printhead acceleration phase. The deviation values ​​of thousands of solder joints within the scan strip are calculated, and a continuous deviation field distribution map is generated using Kriging interpolation. The upper left corner of the strip exhibits an average positive X-axis deviation of 2 micrometers due to mechanical vibration. The deviation field map is meshed to generate a correction matrix for each scan line. For example, the correction matrix for the first scan line is shown at X=10mm, requiring the ignition position to be advanced by 0.5 micrometers to compensate for the deviation. The current scan speed is 1 m / s, the printhead's maximum ignition frequency is 30 kHz, the calculated minimum jettable physical spacing is 3 micrometers, and the pixel spacing in the high-density line area is only 25 micrometers. An empty stroke is automatically inserted in this area, skipping one point every four printed points, reducing the actual ignition frequency to 24 kHz for safety. Convolving the ignition slice of the high-density area with the crosstalk coupling matrix predicts that simultaneous ignition will cause approximately 3% deviation of the ink droplets in the middle nozzle. Deconvolution correction is applied to grayscale values, and a 0.5-microsecond phase delay is inserted between adjacent nozzles to stagger ignition and suppress crosstalk. The first 10mm of the strip is an acceleration section. The planner generates a pre-jet compensation table based on feedforward correction terms, instructing the printhead to ignite slightly earlier than normal in this section to compensate for lag caused by slower speed. The middle 80mm of the uniform speed precision printing section is a uniform speed section. The planner generates a main jet timing table based on optimized ignition sequence and steady-state correction terms, accurately printing all lines. The last 10mm of the deceleration buffer section is a deceleration section. The planner generates residual ink management instructions and adjusts the waveform to prevent excess ink droplets during deceleration. The current strip ends, and the next strip begins. The trajectory smoothing optimizer generates an S-shaped acceleration / deceleration curve to smoothly change the printhead direction. Simultaneously, a tiny reverse backlash compensation pulse is superimposed at the reversal point to eliminate backlash in the drive screw. High-density lines on the circuit board are also printed clearly and accurately in the acceleration section, with no satellite points or streaks at the splicing points.

[0039] Step S104: The gradient ignition waveform signal is transmitted to the FPGA logic unit of the nozzle control board through a high-speed serial interface. The FPGA logic unit triggers the ignition operation of the corresponding nozzle at the precise spatiotemporal coordinate point after dynamic deviation tensor correction according to the timing node of the adaptive dynamic scanning path planning, and completes the printing task of the current scanning strip. The feedback voltage signal of the nozzle is used to determine whether there is a blocked nozzle or an abnormal nozzle, and the nozzle status data is updated to the ignition pulse density map in real time. The abnormal nozzle is compensated by printing with adjacent nozzles.

[0040] In this embodiment, gradient ignition waveform signals are transmitted via a high-speed serial interface, ensuring that massive amounts of printing data can be transmitted from the main control system to the printhead control board in real time without loss. Combined with the hardware parallel processing capabilities of the FPGA logic unit, nanosecond-level response to ignition commands is achieved, fundamentally solving the data transmission bottleneck and execution latency problems in high-speed printing. The FPGA logic unit strictly follows the timing nodes of the adaptive dynamic scanning path planning and triggers ignition at precise spatiotemporal coordinates after dynamic deviation tensor correction. This means that all the complex calculations and optimizations in the early stages (path planning, deviation correction, waveform generation) can ultimately be physically executed accurately, ensuring that each ink droplet is ejected at the calculated optimal position and time. By monitoring the feedback voltage signal of the nozzle in real time, the working status of each nozzle (whether it is blocked or abnormal) can be dynamically determined during the printing process. Once an abnormality is detected, the status data is immediately updated to the ignition pulse density map, and the algorithm schedules nearby normal nozzles for compensation printing. This method of printing, detecting, and repairing simultaneously avoids printing defects caused by individual nozzle failures, significantly improving printing yield and continuity.

[0041] According to the solution provided by the present invention, an ignition pulse density map corresponding to each nozzle is generated based on the CIP4 digital workflow file of the image to be printed. Each pixel in the ignition pulse density map includes an absolute coordinate vector, a grayscale level value, and a channel identifier. Based on the linear array layout of the nozzles on the printhead chassis, the staggered offset of the printhead module, and the ignition pulse density map, the starting absolute coordinates, ending absolute coordinates, the dwell time threshold of the printhead during strip reversal, the overlapping coverage area between scan strips, and the feathering transition width are calculated for each scan strip. Real-time position coordinates, instantaneous velocity, instantaneous acceleration, the mass inertia parameters of the printhead module, and the thrust fluctuation coefficient of the linear motor are input to the motion trajectory predictor to predict the predicted motion trajectory curve of the printhead over multiple future sampling periods. The starting absolute coordinates, ending absolute coordinates, the dwell time threshold of the printhead during strip reversal, the overlapping coverage area between scan strips, the feathering transition width, and the predicted motion trajectory curve for each scan strip are input. The system uses a spatiotemporal synchronization processor to construct a dynamic deviation tensor between the target spatial coordinates of all executable printing units within the current scan strip and the predicted arrival position of the printhead. Based on the droplet flight time compensation model during the ejection process and the piezoelectric crystal hysteresis coefficient during the printhead's acceleration and deceleration phases, it calculates the actual landing time offset and actual landing spatial offset of the droplets from the nozzle to the substrate surface. Based on the dynamic deviation tensor, actual landing spatial offset, the printhead's maximum firing frequency limit, and crosstalk suppression parameters between nozzles, it generates an adaptive dynamic scanning path for the current scan strip to eliminate streak defects caused by printhead speed fluctuations and splicing misalignments caused by mechanical backlash. The adaptive dynamic scanning path and the grayscale value of each executable printing unit are input to a waveform generation unit to generate a gradient firing waveform signal adapted to the piezoelectric printhead. The gradient firing waveform signal is then temperature-compensated and corrected based on the real-time temperature value fed back from the printhead temperature sensor to ensure droplet volume and velocity consistency at different temperatures. The gradient ignition waveform signal is transmitted to the FPGA logic unit of the printhead control board via a high-speed serial interface. The FPGA logic unit, based on the timing nodes planned by the adaptive dynamic scanning path, triggers the ignition operation of the corresponding nozzle at the precise spatiotemporal coordinate point after dynamic deviation tensor correction, completing the printing task of the current scan strip. The feedback voltage signal from the nozzle determines whether there are blocked or abnormal nozzles, and the nozzle status data is updated in real-time to the ignition pulse density map. Abnormal nozzles are compensated by printing with adjacent nozzles. This invention dynamically divides the printing process into three segments based on real-time motion: accelerated pre-spraying, uniform speed fine printing, and deceleration recovery, embedding an S-shaped reversal curve and micro-motion hysteresis compensation. This effectively improves the printing stroke utilization rate while eliminating streaks and splicing misalignment. The overlapping area is calculated in real-time based on multi-nozzle installation deviations and motion deformation, and the feathering width is optimized by combining image texture features to achieve seamless splicing at high speeds, avoiding white gaps or overexposure.

[0042] Figure 4 A schematic diagram of the framework of a reciprocating high-speed inkjet printing path optimization device based on spatiotemporal synchronization control according to an embodiment of the present invention is shown. The reciprocating high-speed inkjet printing path optimization device based on spatiotemporal synchronization control includes: The strip planning module 410 is used to generate an ignition pulse density map corresponding to each nozzle based on the CIP4 digital workflow file of the image to be printed. Each pixel in the ignition pulse density map includes an absolute coordinate vector, a gray level value, and a channel identifier. Based on the linear array layout of the nozzles on the printhead chassis, the staggered offset of the printhead module, and the ignition pulse density map, the module calculates the starting absolute coordinates, ending absolute coordinates, the dwell time threshold of the printhead when the strip changes direction, the overlapping coverage area between the scan strips, and the feathering transition width for each scanning strip. The motion prediction and spatiotemporal deviation calculation module 420 is used to input real-time position coordinates, instantaneous motion velocity, instantaneous acceleration, mass inertia parameters of the printhead module, and thrust fluctuation coefficient of the linear motor into the motion trajectory predictor to predict the predicted motion trajectory curve of the printhead in multiple future sampling periods; input the starting absolute coordinates, ending absolute coordinates, dwell cooling time threshold of the printhead when the strip changes direction, overlapping coverage area between scanning strips, feathering transition width, and predicted motion trajectory curve of each scanning strip into the spatiotemporal synchronization processor to construct the dynamic deviation tensor between the target spatial coordinates of all executable printing units in the current scanning strip and the predicted arrival position of the printhead; and calculate the actual landing point time offset and actual landing point spatial offset of the ink droplet from the nozzle to the substrate surface based on the time-of-flight compensation model of the ink droplet during the ejection process and the piezoelectric crystal hysteresis effect coefficient of the printhead during the acceleration and deceleration phase. The dynamic path planning and waveform generation module 430 is used to generate an adaptive dynamic scanning path for the current scanning strip based on the dynamic deviation tensor, the actual landing point spatial offset, the maximum ignition frequency limit of the printhead, and the crosstalk suppression parameters between nozzles. This path is used to eliminate streak defects caused by printhead speed fluctuations and splicing misalignment caused by mechanical backlash. The adaptive dynamic scanning path and the grayscale level value of each executable printing unit are input to the waveform generation unit to generate a gradient ignition waveform signal adapted to the piezoelectric printhead. The gradient ignition waveform signal is temperature compensated and corrected based on the real-time temperature value fed back by the printhead temperature sensor to ensure the consistency of ink droplet volume and velocity at different temperatures. The printing execution and feedback module 440 is used to transmit the gradient ignition waveform signal to the FPGA logic unit of the printhead control board through a high-speed serial interface. The FPGA logic unit triggers the ignition operation of the corresponding nozzle at the precise spatiotemporal coordinate point after dynamic deviation tensor correction according to the timing node of the adaptive dynamic scanning path planning, and completes the printing task of the current scan strip. The feedback voltage signal of the nozzle is used to determine whether there is a blocked nozzle or an abnormal nozzle, and the nozzle status data is updated to the ignition pulse density map in real time. For abnormal nozzles, the neighboring nozzles are used for compensation printing.

[0043] Figure 5 The diagram shows a structural schematic of an embodiment of the computing device of the present invention. The specific embodiments of the present invention do not limit the specific implementation of the computing device.

[0044] like Figure 5 As shown, the computing device may include: a processor 502, a communications interface 504, a memory 506, and a communications bus 508.

[0045] The processor 502, communication interface 504, and memory 506 communicate with each other via communication bus 508. Communication interface 504 is used to communicate with other network elements, such as clients or other servers. Processor 502 executes program 510, specifically performing the relevant steps in the above-described embodiment of the reciprocating high-speed inkjet printing path optimization method based on spatiotemporal synchronization control.

[0046] Specifically, program 510 may include program code that includes computer operation instructions.

[0047] Processor 502 may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement embodiments of the present invention. The computing device includes one or more processors, which may be processors of the same type, such as one or more CPUs; or processors of different types, such as one or more CPUs and one or more ASICs.

[0048] Memory 506 is used to store program 510. Memory 506 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0049] According to the solution provided by the present invention, an ignition pulse density map corresponding to each nozzle is generated based on the CIP4 digital workflow file of the image to be printed. Each pixel in the ignition pulse density map includes an absolute coordinate vector, a grayscale level value, and a channel identifier. Based on the linear array layout of the nozzles on the printhead chassis, the staggered offset of the printhead module, and the ignition pulse density map, the starting absolute coordinates, ending absolute coordinates, the dwell time threshold of the printhead during strip reversal, the overlapping coverage area between scan strips, and the feathering transition width are calculated for each scan strip. Real-time position coordinates, instantaneous velocity, instantaneous acceleration, the mass inertia parameters of the printhead module, and the thrust fluctuation coefficient of the linear motor are input to the motion trajectory predictor to predict the predicted motion trajectory curve of the printhead over multiple future sampling periods. The starting absolute coordinates, ending absolute coordinates, the dwell time threshold of the printhead during strip reversal, the overlapping coverage area between scan strips, the feathering transition width, and the predicted motion trajectory curve for each scan strip are input. The system uses a spatiotemporal synchronization processor to construct a dynamic deviation tensor between the target spatial coordinates of all executable printing units within the current scan strip and the predicted arrival position of the printhead. Based on the droplet flight time compensation model during the ejection process and the piezoelectric crystal hysteresis coefficient during the printhead's acceleration and deceleration phases, it calculates the actual landing time offset and actual landing spatial offset of the droplets from the nozzle to the substrate surface. Based on the dynamic deviation tensor, actual landing spatial offset, the printhead's maximum firing frequency limit, and crosstalk suppression parameters between nozzles, it generates an adaptive dynamic scanning path for the current scan strip to eliminate streak defects caused by printhead speed fluctuations and splicing misalignments caused by mechanical backlash. The adaptive dynamic scanning path and the grayscale value of each executable printing unit are input to a waveform generation unit to generate a gradient firing waveform signal adapted to the piezoelectric printhead. The gradient firing waveform signal is then temperature-compensated and corrected based on the real-time temperature value fed back from the printhead temperature sensor to ensure droplet volume and velocity consistency at different temperatures. The gradient ignition waveform signal is transmitted to the FPGA logic unit of the printhead control board via a high-speed serial interface. The FPGA logic unit, based on the timing nodes planned by the adaptive dynamic scanning path, triggers the ignition operation of the corresponding nozzle at the precise spatiotemporal coordinate point after dynamic deviation tensor correction, completing the printing task of the current scan strip. The feedback voltage signal from the nozzle determines whether there are blocked or abnormal nozzles, and the nozzle status data is updated in real-time to the ignition pulse density map. Abnormal nozzles are compensated by printing with adjacent nozzles. This invention dynamically divides the printing process into three segments based on real-time motion: accelerated pre-spraying, uniform speed fine printing, and deceleration recovery, embedding an S-shaped reversal curve and micro-motion hysteresis compensation. This effectively improves the printing stroke utilization rate while eliminating streaks and splicing misalignment. The overlapping area is calculated in real-time based on multi-nozzle installation deviations and motion deformation, and the feathering width is optimized by combining image texture features to achieve seamless splicing at high speeds, avoiding white gaps or overexposure.

[0050] Those skilled in the art will understand that modules in the device of the embodiments can be adaptively changed and placed in one or more devices different from that embodiment. Modules, units, or components in the embodiments can be combined into a single module, unit, or component, and further, they can be divided into multiple sub-modules, sub-units, or sub-components. Except where at least some of such features and / or processes or units are mutually exclusive, any combination of all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or units of any method or device so disclosed can be employed. Unless expressly stated otherwise, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature that serves the same, equivalent, or similar purpose. Furthermore, those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of the invention and form different embodiments. For example, in the following claims, any of the claimed embodiments can be used in any combination. The invention can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims listing several devices, several of these devices may be embodied by the same hardware item. Unless otherwise specified, the steps in the above embodiments should not be construed as limiting the order of execution.

Claims

1. A method for optimizing the path of a reciprocating high-speed inkjet printing system based on spatiotemporal synchronization control, characterized in that, include: The ignition pulse density map for each nozzle is generated based on the CIP4 digital workflow file of the image to be printed. Each pixel in the ignition pulse density map includes an absolute coordinate vector, a gray level value, and a channel identifier. Based on the linear array layout of the nozzles on the printhead chassis, the staggered offset of the printhead module, and the ignition pulse density map, the starting absolute coordinates, ending absolute coordinates, the dwell time threshold of the printhead when the strip changes direction, the overlapping coverage area between the scan strips, and the feathering transition width are calculated for each scan strip. The real-time position coordinates, instantaneous velocity, instantaneous acceleration, mass inertia parameters of the printhead module, and thrust fluctuation coefficient of the linear motor are input into the motion trajectory predictor to predict the printhead's motion trajectory curve over multiple future sampling periods. The starting absolute coordinates, ending absolute coordinates, printhead dwell cooling time threshold during strip reversal, overlapping coverage area between scan strips, feathering transition width, and predicted motion trajectory curve of each scan strip are input into the spatiotemporal synchronization processor to construct the dynamic deviation tensor between the target spatial coordinates of all executable printing units within the current scan strip and the predicted arrival position of the printhead. Based on the time-of-flight compensation model of ink droplets during the ejection process and the piezoelectric crystal hysteresis effect coefficient of the printhead during acceleration and deceleration, the actual landing point time offset and actual landing point spatial offset of the ink droplets from the nozzle to the substrate surface are calculated. Based on the dynamic deviation tensor, actual landing point spatial offset, printhead maximum firing frequency limit, and crosstalk suppression parameters between nozzles, an adaptive dynamic scanning path is generated for the current scanning strip to eliminate streak defects caused by printhead speed fluctuations and splicing misalignment caused by mechanical backlash. The adaptive dynamic scanning path and the grayscale level value of each executable printing unit are input to the waveform generation unit to generate a gradient firing waveform signal adapted to the piezoelectric printhead. The gradient firing waveform signal is temperature compensated and corrected based on the real-time temperature value fed back by the printhead temperature sensor to ensure the consistency of ink droplet volume and velocity at different temperatures. The gradient ignition waveform signal is transmitted to the FPGA logic unit of the nozzle control board through a high-speed serial interface. The FPGA logic unit triggers the ignition operation of the corresponding nozzle at the precise spatiotemporal coordinate point after dynamic deviation tensor correction according to the timing node of the adaptive dynamic scanning path planning, and completes the printing task of the current scanning strip. The feedback voltage signal of the nozzle is used to determine whether there is a blocked nozzle or an abnormal nozzle, and the nozzle status data is updated to the ignition pulse density map in real time. For abnormal nozzles, the neighboring nozzles are used for compensation printing.

2. The method for optimizing the reciprocating high-speed inkjet printing path based on spatiotemporal synchronization control according to claim 1, characterized in that, Generating an ignition pulse density map for each nozzle based on the CIP4 digital workflow file of the image to be printed further includes: Obtain the CIP4 digital workflow file of the image to be printed, and parse the CIP4 digital workflow file using a RIP raster image processor to generate a digital matrix of printing areas including the four CMYK color channels; The digital matrix of the printing area is matched with the physical resolution parameters of the nozzle to generate an ignition pulse density map corresponding to each nozzle.

3. The method for optimizing the reciprocating high-speed inkjet printing path based on spatiotemporal synchronization control according to claim 1, characterized in that, The calculation of the starting absolute coordinates, ending absolute coordinates, nozzle dwell-cooling time threshold during strip reversal, overlapping coverage area between scan strips, and feathering transition width for each scan strip further includes: Based on the linear array layout of the nozzles on the nozzle chassis, the staggered offset of the nozzle modules, and the ignition pulse density map, the printing area is divided into several parallel scanning strips along the media feed direction. Assign a strip index number to each scan strip and calculate the starting absolute coordinates, ending absolute coordinates, and the dwell time threshold of the nozzle when the strip changes direction for each scan strip; The overlapping coverage area and feathering transition width between scanning strips are determined based on the splicing error compensation value between the physical width of the nozzle and adjacent nozzles.

4. The method for optimizing the reciprocating high-speed inkjet printing path based on spatiotemporal synchronization control according to claim 1, characterized in that, The predicted motion trajectory curves of the nozzle over multiple sampling periods further include: The orthogonal coded pulse signal output by the grating ruler feedback system is acquired in real time. The orthogonal coded pulse signal is subjected to a fourth frequency harmonic processing by the motion controller to calculate the real-time position coordinates, instantaneous motion velocity and instantaneous acceleration of the nozzle module in the X-axis scanning direction. The real-time position coordinates, instantaneous velocity, instantaneous acceleration, mass inertia parameters of the nozzle module, and thrust fluctuation coefficient of the linear motor are input into the motion trajectory predictor to predict the motion trajectory curve of the nozzle in multiple future sampling periods. The predicted motion trajectory curve includes the predicted position sequence, predicted velocity sequence, and predicted acceleration sequence corresponding to the timestamp.

5. The method for optimizing the reciprocating high-speed inkjet printing path based on spatiotemporal synchronization control according to claim 1, characterized in that, The adaptive dynamic scanning path includes segmented motion control parameters for the pre-spray compensation zone of the printhead in the acceleration phase, the normal spray zone in the constant speed phase, and the residual ink recovery zone in the deceleration phase, as well as S-shaped acceleration and deceleration curve parameters and reverse gap compensation parameters at the reversal points at both ends of the scanning strip. The gradient ignition waveform signal includes voltage amplitude step parameters that control the droplet volume, trigger delay time that controls the droplet ejection phase, and pulse width modulation curve that controls the droplet breakage velocity.

6. The method for optimizing the reciprocating high-speed inkjet printing path based on spatiotemporal synchronization control according to claim 1, characterized in that, Based on the time-of-flight compensation model of ink droplets during the ejection process and the piezoelectric crystal hysteresis coefficient of the printhead during acceleration and deceleration, the actual time offset and actual spatial offset of the ink droplets from the nozzle to the substrate surface are calculated, including: With the nozzle module stationary, a set of stepped scanning voltage signals covering the entire voltage range are applied to the test nozzle of the piezoelectric nozzle. The mechanical displacement response curves of the piezoelectric crystal under different voltage excitations are collected by a laser Doppler vibration meter installed below the nozzle. The mechanical displacement response curves are differentiated to extract the displacement voltage hysteresis loop characteristic parameters of the piezoelectric crystal at the rising and falling edges. The displacement voltage hysteresis loop characteristic parameters include the maximum displacement amplitude, the rising response time constant, and the falling response time constant. The displacement voltage hysteresis loop characteristic parameters are fitted to the Preisach hysteresis mathematical model to generate a piezoelectric crystal hysteresis effect coefficient matrix describing the nonlinear response of the piezoelectric crystal under dynamic driving conditions; the real-time acceleration value of the printhead module and the physical spraying distance between the nozzle and the substrate surface are obtained during the acceleration and deceleration phases; and an analytical model of ink droplet flight time is constructed based on the ink droplet flight motion equation in fluid mechanics. The real-time acceleration value is input into the predicted motion trajectory curve to calculate the vertical vibration component of the nozzle at the current moment; the vertical vibration component is superimposed on the physical jet spacing to generate the dynamic jet spacing; the dynamic jet spacing is substituted into the ink droplet flight time analytical model to calculate the basic flight time of the ink droplet under the current acceleration condition. The rise and fall response time constants in the piezoelectric crystal hysteresis effect coefficient matrix are convolved with the basic flight time to construct the printhead droplet composite response time model. Based on the voltage change direction and voltage change amplitude corresponding to the printhead drive waveform at the current moment, the corresponding comprehensive response delay time is retrieved from the printhead droplet composite response time model. The nominal response time of the printhead under static calibration conditions is subtracted from the comprehensive response delay time to calculate the actual landing point time offset caused by the combined effect of piezoelectric hysteresis and printhead vibration. Input the actual landing point time offset into the predicted motion trajectory curve, and query the displacement increment of the printhead in the X-axis scanning direction within the time offset interval; at the same time, based on the instantaneous velocity vector of the printhead during the acceleration and deceleration phase and the vertical vibration component, calculate the lateral offset component and longitudinal offset component of the ink droplet during flight due to the coupling effect of the horizontal movement and vertical vibration of the printhead. The displacement increment, lateral offset component, and longitudinal offset component are vector-superimposed to generate the actual landing point spatial offset vector of the ink droplet relative to the nozzle center position; the actual landing point time offset and the actual landing point spatial offset vector are encapsulated into an ink droplet landing point spatiotemporal offset pair; the ink droplet landing point spatiotemporal offset pair is output to the spatiotemporal synchronization processor and matrix-added with the dynamic deviation tensor to generate a full-element dynamic deviation tensor that simultaneously includes nozzle motion deviation, piezoelectric hysteresis deviation, and ink droplet flight deviation.

7. The method for optimizing the reciprocating high-speed inkjet printing path based on spatiotemporal synchronization control according to claim 6, characterized in that, Based on the dynamic deviation tensor, the actual landing point spatial offset, the nozzle's maximum ignition frequency limit, and the crosstalk suppression parameters between nozzles, an adaptive dynamic scanning path for the current scanning strip is generated, which further includes: Spatiotemporal deviation fusion is performed based on the dynamic deviation tensor of all elements and the spatial offset vector of the actual landing point. The deviation values ​​of all discrete executable printing units within the scan strip are fitted to a surface using the Kriging interpolation algorithm to reconstruct a continuous spatiotemporal deviation field distribution map covering the entire scan strip. The continuous spatiotemporal deviation field distribution map is divided into grids according to the width of a single nozzle scan, and a row deviation correction matrix is ​​generated for each scan line. The row deviation correction matrix contains a sequence of correction weight coefficients that are equally spaced along the X-axis. Based on the maximum ignition frequency limit, minimum ignition interval time, and instantaneous velocity sequence specified in the printhead datasheet, the minimum jettable physical spacing of the printhead in the X-axis direction at the current scanning speed is calculated. The minimum jettable physical spacing is compared with the pixel physical width of the ignition pulse density map to generate the jet density limit factor for each region within the scan strip. For high-density printing areas where the pixel physical width is smaller than the minimum jettable physical spacing, an empty travel skip node is automatically inserted based on the jet density limit factor to ensure that the actual ignition frequency of the printhead is always lower than the maximum ignition frequency limit, thus avoiding nozzle fatigue and ink droplet satellite phenomenon caused by excessive frequency. Extract the nozzle crosstalk coupling matrix calibrated by the printhead manufacturer, wherein the nozzle crosstalk coupling matrix includes the droplet volume deviation and flight direction deviation caused by acoustic resonance and flow channel mutual interference when adjacent nozzles are ignited simultaneously; input the ignition pulse density map slice corresponding to the current scan line into the crosstalk suppression preprocessor and perform convolution operation with the nozzle crosstalk coupling matrix to predict the actual droplet output state of each nozzle when ignited simultaneously; Based on the actual ink droplet output state, the gray level values ​​in the ignition pulse density map are deconvolutionally compensated and corrected to generate an optimized ignition sequence that suppresses crosstalk effects. At the same time, for high-density nozzle combinations that must be ignited simultaneously, a microsecond-level phase delay is inserted to distribute the concentrated ignition energy evenly on the time axis and avoid instantaneous power overload. The line deviation correction matrix, minimum injectable physical spacing, and optimized ignition sequence are input into the path dynamic planner. Based on the movement stage of the printhead within the scanning strip, the scanning strip is divided into three functional areas: acceleration compensation, constant speed precision printing, and deceleration buffer. In the acceleration compensation section, a pre-jet compensation coordinate table is generated to compensate for the effects of speed fluctuations in advance, based on the real-time acceleration value and the feedforward correction term in the line deviation correction matrix. In the constant speed precision printing section, a main jet timing table that precisely matches the target coordinates is generated based on the optimized ignition sequence and the steady-state correction term in the line deviation correction matrix. In the deceleration buffer section, a residual ink management instruction set is generated to recover excess ink droplets and smoothly stop the printhead, based on the remaining deviation energy and printhead inertia parameters. The absolute coordinates of the nozzle at the end of the current scanning strip and the absolute coordinates of the beginning of the next scanning strip are obtained, and the reversing span during strip switching is calculated. The reversing span, the mass inertia parameters of the nozzle module, and the maximum acceleration limit of the linear motor are input into the trajectory smoothing optimizer to generate S-shaped acceleration and deceleration curve parameters connecting the two scanning strips. The S-shaped acceleration and deceleration curve parameters include acceleration limit value, maximum speed inflection point, and backlash compensation amount. The backlash compensation amount is superimposed on the area near the reversing point of the line deviation correction matrix to generate a micro-motion backlash correction pulse for eliminating mechanical transmission backlash. The pre-jet compensation coordinate table, main jet timing table, residual ink management instruction set, S-shaped acceleration / deceleration curve parameters, and micro-motion hysteresis correction pulse are encapsulated to generate an adaptive dynamic scanning path data packet including a timestamp sequence, position coordinate sequence, and ignition control word. The adaptive dynamic scanning path data packet is output to the waveform generation unit to ensure that each nozzle can complete ink droplet ejection at a precise spatiotemporal coordinate point during high-speed reciprocating motion of the printhead, thereby eliminating streaks and splicing misalignments.

8. The method for optimizing the reciprocating high-speed inkjet printing path based on spatiotemporal synchronization control according to claim 3, characterized in that, The overlapping coverage area and feathering transition width between scanning strips are determined based on the splicing error compensation value between adjacent nozzles and the physical width of the nozzle. This further includes: A standard quartz grating plate is installed on the printing platform as a calibration reference to control the sequential movement of each printhead module to the calibration position. A microscopic vision camera mounted on the printhead bracket acquires the projected images of the nozzle arrays of each printhead on the standard quartz grating plate. Subpixel-level edge extraction is performed on the projected images, and the actual installation coordinates of each printhead relative to the platform coordinate origin are calculated. The actual installation coordinates include X-axis offset, Y-axis offset, and rotation angle deviation. The actual installation coordinates of each printhead are then differentially analyzed with their theoretical design coordinates to generate a multi-printhead installation deviation matrix describing the relative positional relationship between the printheads. This multi-printhead installation deviation matrix includes the horizontal splicing deviation of adjacent printheads in the X-axis direction, the vertical alignment deviation in the Y-axis direction, and the angular torsional deviation around the Z-axis. The multi-nozzle installation deviation matrix is ​​input into the rigid body kinematics model. Combined with the instantaneous velocity vector and real-time acceleration value of the nozzle during the acceleration and deceleration phases, the dynamic deformation of the nozzle caused by inertial force and centrifugal force during high-speed reciprocating motion is calculated. The dynamic deformation is superimposed on the multi-nozzle installation deviation matrix to generate a dynamic splicing error compensation value sequence that changes in real time with the nozzle motion state. The dynamic splicing error compensation value sequence includes time-varying compensation coefficients that are equally spaced along the X-axis direction of the scanning strip. Obtain the physical width W of the nozzle and the theoretical spacing D between adjacent nozzles. Combine the maximum positive deviation and the maximum negative deviation in the dynamic splicing error compensation value sequence to calculate the effective coverage width between the scanning strips of adjacent nozzles. Multiply the basic overlap width by the safety redundancy coefficient to generate the final determined overlap coverage area width value. This ensures that there is always physical overlap between the scanning strips of adjacent nozzles under different movement speeds and acceleration conditions, avoiding gaps caused by dynamic deviations. The width value of the overlapping coverage area is input into the feathering parameter optimizer, and the optimal feathering transition width matching the current image content is calculated by combining the image texture features in the overlapping area of ​​the ignition pulse density map. The width of the overlapping coverage area and the optimal feathering transition width are encapsulated into a splicing compensation parameter set. This splicing compensation parameter set is output to the scanning strip division module as a boundary constraint condition when dividing parallel scanning strips. The splicing compensation parameter set is transmitted to the path dynamic planner. When generating an adaptive dynamic scanning path, the ignition timing of the overlapping coverage area is coordinated and scheduled by two printheads to ensure that the two printheads eject ink droplets sequentially or simultaneously at the same physical position according to the assigned weight coefficient, thereby achieving sub-pixel-level seamless fusion of the splicing area.

9. A reciprocating high-speed inkjet printing path optimization device based on spatiotemporal synchronization control, characterized in that, include: The strip planning module is used to generate an ignition pulse density map corresponding to each nozzle based on the CIP4 digital workflow file of the image to be printed. Each pixel in the ignition pulse density map includes an absolute coordinate vector, a gray level value, and a channel identifier. Based on the linear array layout of the nozzles on the printhead chassis, the staggered offset of the printhead module, and the ignition pulse density map, the module calculates the starting absolute coordinates, ending absolute coordinates, the dwell time threshold of the printhead when the strip changes direction, the overlapping coverage area between the scan strips, and the feathering transition width for each scanning strip. The motion prediction and spatiotemporal deviation calculation module is used to input real-time position coordinates, instantaneous velocity, instantaneous acceleration, mass inertia parameters of the printhead module, and thrust fluctuation coefficient of the linear motor into the motion trajectory predictor to predict the printhead's motion trajectory curve over multiple sampling periods. It inputs the starting absolute coordinates, ending absolute coordinates, printhead dwell-cooling time threshold during strip reversal, overlapping coverage area between scan strips, feathering transition width, and predicted motion trajectory curve of each scan strip into the spatiotemporal synchronization processor to construct the dynamic deviation tensor between the target spatial coordinates of all executable printing units within the current scan strip and the predicted arrival position of the printhead. Based on the time-of-flight compensation model of ink droplets during the ejection process and the piezoelectric crystal hysteresis coefficient of the printhead during acceleration and deceleration, it calculates the actual landing point time offset and actual landing point spatial offset of the ink droplets from the nozzle to the substrate surface. The dynamic path planning and waveform generation module generates an adaptive dynamic scanning path for the current scan strip based on the dynamic deviation tensor, actual landing point spatial offset, printhead maximum firing frequency limit, and crosstalk suppression parameters between nozzles. This path eliminates streak defects caused by printhead speed fluctuations and splicing misalignment caused by mechanical backlash. The adaptive dynamic scanning path and the grayscale level value of each executable printing unit are input to the waveform generation unit to generate a gradient firing waveform signal adapted to the piezoelectric printhead. The gradient firing waveform signal is then temperature-compensated and corrected based on the real-time temperature value fed back by the printhead temperature sensor to ensure the consistency of ink droplet volume and velocity at different temperatures. The printing execution and feedback module transmits the gradient ignition waveform signal to the FPGA logic unit of the printhead control board via a high-speed serial interface. The FPGA logic unit triggers the ignition operation of the corresponding nozzle at the precise spatiotemporal coordinate point after dynamic deviation tensor correction, based on the timing nodes planned by the adaptive dynamic scanning path, to complete the printing task of the current scan strip. The module also uses the feedback voltage signal of the nozzle to determine whether there is a blocked or abnormal nozzle and updates the nozzle status data to the ignition pulse density map in real time, performing neighboring nozzle compensation printing for abnormal nozzles.

10. A computing device, comprising: The processor, memory, communication interface, and communication bus are provided, wherein the processor, memory, and communication interface communicate with each other via the communication bus. The memory is used to store at least one executable instruction, which causes the processor to perform the operation corresponding to the above-described reciprocating high-speed inkjet printing path optimization method based on spatiotemporal synchronization control.

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