A method and apparatus for full-circumferential inkjet printing on a curved object surface and a storage medium

Abstract

This invention relates to the field of digital inkjet printing technology, specifically to a method, device, and storage medium for full-circumference inkjet printing on the surface of curved objects. The method includes calculating the total number of physical ink dots around the circumference of the curved object and the printer resolution; using image processing to precisely match the total number of pixels around the pattern, the total number of encoder signals, and the total number of physical ink dots to achieve seamless 360° splicing; for irregular curved surfaces, three-dimensional data is acquired through contour scanning, and the number of ink dots is dynamically adjusted based on the perimeter ratio to achieve adaptive dot-mapping printing. The printing device includes a clamping device, a printhead module, a crossbeam, a printhead, an encoder, and a control unit, adaptable to printing on the inner and outer surfaces of various curved objects. This invention offers advantages such as high splicing accuracy, stable image quality, wide surface adaptability, and strong industrial adaptability, effectively meeting the needs of small-batch flexible production and large-scale mass production.

Description

Technical Field

[0001] This invention relates to the field of digital inkjet printing technology, specifically to a method, equipment, and storage medium for full-circumference inkjet printing on the surface of a curved object. Background Technology

[0002] Inkjet printing technology, with its core advantages such as non-contact printing, high-resolution output, and wide applicability to various substrates, has been widely used in industrial and civilian fields such as product surface decoration, marking and coding, and personalized customization. Against the backdrop of the increasing demand for printing on curved surfaces, traditional curved surface printing solutions such as transfer printing and screen printing have inherent drawbacks, including long plate-making cycles, high upfront costs, and difficulty in adapting to small-batch flexible production, thus failing to meet the demands of modern manufacturing for personalized and rapid-response production.

[0003] Most mainstream inkjet printers are designed for flat or near-flat substrates. When applied to 360° full-circumference printing on curved surfaces such as cylindrical (e.g., fishing rods, thermos cups), spherical (e.g., toy balls), and irregularly shaped (e.g., helmets, electronic device casings), they face many technical bottlenecks. If the curved surface is simply unfolded into a plane for pattern mapping and the print head is positioned in a fixed position to spray, with the workpiece being carried by a rotating platform, problems such as incomplete circumference division, perspective distortion, and uneven linear velocity on the curved surface will cause the printed pattern to fail to stitch together completely, and the cumulative error will result in blurry image quality and inconsistent resolution. To print on curved surfaces, current solutions mainly fall into three categories: First, a simple rotary platform inkjet printing solution, which uses a fixed printhead in conjunction with a rotating platform to move the workpiece and directly map the 2D image onto the cylindrical surface for printing. However, this solution is only suitable for standard cylinders, cannot correct perspective distortion on curved surfaces, and suffers from low printing accuracy. Second, a robot arm-held printhead printing solution, which uses an industrial robot to move the printhead around a fixed workpiece. While offering high flexibility, it suffers from high system costs, complex trajectory programming, and low printing efficiency, making it difficult to integrate into large-scale production lines. Third, a high-speed rotary printing solution, which uses a code disk and algorithms to achieve uniform dot distribution and can initially achieve 360° splicing, but it does not solve the problem of uneven printing accuracy caused by the geometric characteristics of curved surfaces.

[0004] Specifically, the core shortcomings of existing technologies are concentrated in the following aspects: First, seamless splicing is difficult, as the mismatch between the substrate circumference and the number of image pixels leads to misalignment at the splicing points of the entire pattern; second, printing accuracy is insufficient, failing to consider the accumulation of errors during circumferential printing, resulting in blurred image edges and loss of details; third, printing consistency is poor, as differences in the linear velocity of the printhead relative to different positions on the curved surface cause varying ink droplet reception per unit area, resulting in uneven pattern density; fourth, inkjet distance control is challenging, as the distance between the workpiece surface and the printhead dynamically changes during the rotation of non-cylindrical curved surfaces, with excessive distance causing ink droplet deviation and decreased accuracy, while excessive proximity poses a risk of collision; fifth, the system is economically inefficient, with the high cost and maintenance difficulty of robotic solutions limiting their industrial application. Therefore, developing a 360° curved surface full-circumference inkjet printing control technology that can achieve high precision, seamless splicing, and high consistency has become an urgent technical problem to be solved in this field. Summary of the Invention

[0005] The purpose of this invention is to provide a method and apparatus for full-circumference inkjet printing on the surface of curved objects, so as to solve the problems mentioned in the background art.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A method for full-circumference inkjet printing of a curved object surface includes the following steps: S1. Calculation of the total number of physical ink dots: Obtain the rotational circumference of the curved object and the resolution of the printer in the rotational direction. Calculate the total number of physical ink dots required for the curved object to rotate one revolution using the formula N = (C÷25.4) × D, and round up. Where C is the rotational circumference in mm; D is the resolution in dpi; and N is the total number of physical ink dots. S2. Pattern pixel matching: The printing software processes the circumferential image data of the target pattern so that the total number of pixels required for the pattern to circle the curved object is equal to the total number of physical ink dots. S3. Encoder configuration: Set an external encoder so that when the curved object rotates one revolution, the total number of signals output by the encoder is equal to the total number of physical ink dots; S4. Collaborative Printing Control: The curved object rotates continuously and uniformly around its own axis, triggering the printhead to eject ink dots one by one according to the signal output by the encoder, while controlling the printhead to move uniformly in a direction parallel to the axis of the curved object.

[0007] Furthermore, for irregularly shaped curved objects, an adaptive printing step is also included: S01. Contour Scan: Before printing, perform a full-range contour scan on the irregular curved surface object to obtain its three-dimensional data of the outer contour, and extract the maximum rotation circumference and the actual rotation circumference at different positions along the axis. S02. Dynamic calculation of ink dot count: Based on the ratio of the maximum rotation circumference to the actual rotation circumference at the current position, according to formula N... current =C current ÷C max ×N, dynamically adjusts the number of physical ink dots N in the current rotation cycle. current ; S03, Adaptive Spot Printing: Keeps the total number of encoder output signals constant in each rotation cycle of the object, sets the pixel data corresponding to the excess ink dots in the current rotation cycle to zero, and does not perform inkjet action when the printhead receives zero data, thus realizing spot printing.

[0008] Furthermore, the circumferential image data processing in S2 includes image resampling and pixel-physical position mapping. Specifically, it receives the original pattern file and parses it into a digital image matrix, sets the target pixel width to the total number of physical ink dots, and when the original image width is not equal to the target pixel width, it uses an interpolation algorithm to resample the original image, adjusts the image width to the target pixel width, and establishes a one-to-one correspondence between the image pixel index and the physical position of the curved object surface.

[0009] Furthermore, the printing software employs a band printing algorithm to cut the processed pattern into several band data segments at a constant step height, and then sequentially splices or prints them in segments.

[0010] Furthermore, the implementation of the Band printing algorithm includes: The processed pattern is cut into multiple band data segments along a direction perpendicular to the rotation direction; The data segments of each band are concatenated into a continuous data stream and sent to the printhead in sequence for printing.

[0011] Furthermore, the implementation of the Band printing algorithm includes: The processed pattern is cut into multiple band data segments; Print the data segments in the order of the Bands, and stitch adjacent data segments together in real time according to the rotation angle of the curved object and the movement position of the nozzle.

[0012] Furthermore, the step height is calculated and determined by the printing algorithm based on the printer's resolution and pattern size in the stepping direction.

[0013] Furthermore, the interpolation algorithm includes bilinear interpolation, bicubic interpolation, or the Lanczos resampling algorithm.

[0014] The present invention also provides an inkjet printing device for the entire circumference of a curved object surface, comprising: Clamping device: used to fix curved objects and drive the curved objects to rotate continuously and uniformly around their own axis; Nozzle module: includes at least one nozzle, and the spray direction of all nozzles is parallel to the axis of the curved object; Crossbeam: Extends along the axial direction of the curved object; The nozzle head is slidably mounted on the crossbeam and can move at a constant speed along the crossbeam. The nozzle module is fixedly mounted on the nozzle head. Encoder: Linked with the clamping device, used to emit position feedback signals when the curved object rotates; Control unit: Electrically connected to the clamping device, printhead module, printhead and encoder respectively, for performing the above-described method of full-circumference inkjet printing on curved object surface.

[0015] In addition, the present invention also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the above-described method for full-circumference inkjet printing on the surface of a curved object.

[0016] Due to the adoption of the above technical solution, the technical progress achieved by this invention compared to the prior art is as follows: 1. Achieve 360-degree seamless splicing: Through triple precise synchronization of the total number of physical ink dots, the total number of pattern pixels, and the total number of encoder signals, the problem of misalignment and error accumulation in the whole circle of pattern splicing is completely eliminated, and the splicing accuracy is significantly improved.

[0017] 2. Excellent printing accuracy and consistency: By using image resampling and pixel matching algorithms, it ensures that image pixels correspond one-to-one with physical ink dots. Combined with an adaptive sampling strategy for irregular curved surfaces, it effectively solves the problem of image density differences caused by uneven ink droplet distribution, ensuring stable printing quality across the entire curved surface.

[0018] 3. Wide range of curved surface adaptation: It can flexibly adapt to the printing needs of various curved objects such as cylinders, spheres, variable diameter, cones, and waves, greatly expanding the application scenarios of inkjet printing technology.

[0019] 4. Strong industrial adaptability: The system has a simple structure and high integration. The core algorithm responds quickly and runs stably. It balances printing efficiency and cost control and can be directly integrated into industrial production lines, adapting to the dual needs of small-batch flexible production and large-scale production. Attached Figure Description

[0020] Figure 1 This is a flowchart of the printing method of the present invention; Figure 2 A schematic diagram of the B and processing algorithm; Figure 3 Flowchart for point extraction and printing of irregular curved surfaces; Figure 4 This is a structural diagram of the printing equipment.

[0021] In the diagram: 1-crossbeam; 2-head; 3-nozzle module; 31-nozzle; 4-clamping device; 41-drive mechanism; 5-encoder; 6-control unit. Detailed Implementation

[0022] The present invention will be further described in detail below with reference to embodiments: like Figures 1-4 As shown, this invention provides a full-circumference inkjet printing device for curved object surfaces. Its core components include: a crossbeam 1, a printhead 2, a printhead module 3, a clamping device 4, an encoder 5, and a control unit 6. The printhead module 3 contains multiple printheads 31, all of which have their ink jet direction strictly parallel to the axis of the curved object to be printed. The crossbeam 1 extends parallel to the axis of the curved object, and the printhead 2 is slidably mounted on the crossbeam 1, allowing for smooth and uniform movement along the crossbeam 1. The curved object is precisely fixed by the clamping device 4, which is equipped with a drive mechanism 41 that drives the curved object to rotate continuously and uniformly around its axis. The encoder 5 is linked to the clamping device 4 to collect the rotational position information of the curved object in real time and output feedback signals. The control unit 6 is electrically connected to the printhead 2, printhead module 3, clamping device 4, and encoder 5, respectively, to execute the printing method and achieve coordinated operation of all components.

[0023] The basic workflow is as follows: During the printing process, the control unit 6 synchronously drives the clamping device 4 to rotate the curved object continuously and the print head 2 to move the print head module 3 at a constant speed along the crossbeam 1. The rotational motion and the moving motion are precisely synchronized through the signal of the encoder 5. At the same time, the control unit 6 transmits the processed image data to the print head module 3 according to the preset rules. The encoder 5 triggers the print head 31 to spray ink dots as needed, and finally forms a continuous and complete printed pattern on the surface of the curved object.

[0024] The printing method includes the following steps: S1. Calculation of Total Physical Ink Dots: The rotational circumference C of the curved object to be printed is read by measurement or design drawings. For objects with varying diameters or irregular shapes, the maximum circumference Cmax is taken as the rotational circumference C. The printer's rotational resolution D (dpi, dots per inch) is determined based on the printer's hardware performance. The total number of physical ink dots required for one rotation of the curved object is calculated using the formula N = (C ÷ 25.4) × D, rounded up. Here, C is the rotational circumference in mm; D is the resolution in dpi; N is the total number of physical ink dots; and 25.4 is the conversion factor between inches and millimeters to ensure consistent unit values ​​in the calculation results. S2. Pattern Pixel Matching: The printing software processes the circumferential image data of the target pattern to make the total number of pixels required for the pattern to circle the curved object equal to the total number of physical ink dots. The specific steps are as follows: S21. Image Input and Parsing: The printing software receives the original pattern file input by the user. Supported file formats include, but are not limited to, JPEG, PNG, TIFF, PDF, etc. The printing software parses the original pattern file, converts it into a standardized digital image matrix, and extracts the original pixel dimensions of the image, including width W0 and height H0, as well as the original resolution information. S22. Target pixel width calculation: Based on the total number of physical ink dots N calculated in step S1, determine the target pixel width W1 of the target pattern along the rotation direction of the curved object, i.e., the circumferential direction, so that W1 = N. This setting ensures that each pixel in the circumferential direction of the image can correspond to a physical ink dot, realizing a one-to-one match between pixels and physical ink dots. S23. Image resampling and pixel adjustment: If the width W0 of the original image is not equal to the target pixel width W1, the original image is resampled. The resampling process uses a high-precision interpolation algorithm, including but not limited to bilinear interpolation, bicubic interpolation or Lanczos resampling algorithm, to ensure that there is no obvious distortion after the image is scaled. The core goal of resampling is to accurately adjust the image width to W1, and at the same time adjust the height according to the aspect ratio of the original image to avoid image stretching and deformation, and establish the resampled image matrix. S24. Establishing a pixel-physical position mapping relationship: The control unit 6 establishes a precise mapping relationship between the image pixel index and the physical position on the surface of the curved object through software algorithms; the specific process is as follows: S241. Divide the circumference C of the curved object into N equal parts, and each part of the arc length corresponds to the physical landing point of an ink dot. S242. Bind the i-th circumferential pixel (i = 1, 2, ..., N) of the resampled image to the physical landing point of the i-th ink dot one by one; S243. When the i-th position feedback signal of the encoder arrives, the control unit 6 synchronously sends the color, grayscale, and other data of the i-th pixel of the image to the nozzle module 3 to ensure that the pixel data and the spraying action are accurately synchronized.

[0025] S25. Data Segmentation and Band Processing: To adapt to the synchronous movement of the nozzle 31 and the surface rotation, the resampled image is segmented into several band data segments along the surface axis, i.e., the height direction. The specific process is as follows: S251. Calculate the pixel height H_band of each Band data segment based on the printer's print resolution, the physical coverage area of ​​the printhead 31, and its moving speed. S252. The complete image is uniformly divided into multiple independent Band data segments along the height direction. The width of each Band data segment is W1 and the height is H_band. S253. Select the corresponding Band processing algorithm according to the actual printing requirements. Algorithm 1 concatenates each Band data segment into a whole data strip in sequence before printing. Algorithm 2 prints each Band segment separately and then concatenates them.

[0026] S26. Data transmission and synchronization control: The image data after Band processing is stored in the print buffer. The control unit 6 listens to the position feedback signal of the encoder 5 in real time. Each time a signal from the encoder 5 is received, the pixel data of the corresponding position is read from the print buffer and transmitted to the printhead module 3. The printhead module 3 accurately controls the ink ejection timing, droplet size and number of ink droplets of each printhead 31 according to the received pixel data to achieve high-precision printing.

[0027] S3, Encoder Configuration: Set the signal output rules of encoder 5 so that when the curved object rotates one revolution, the total number of signals output by encoder 5 is strictly equal to the total number of physical ink dots N. S4. Cooperative Printing Control: When printing is started, the clamping device 4 tightly clamps and drives the curved object to rotate continuously and uniformly around its own axis. The control unit 6 triggers the printhead 31 to eject ink dots one by one according to the signal output by the encoder 5. At the same time, it controls the printhead 31 to move uniformly in a direction parallel to the axis of the curved object, ensuring that the timing of each ink dot ejection corresponds precisely to the rotation position of the curved object, so as to achieve continuous printing.

[0028] For irregular curved surfaces with varying diameters, consistency in printing across the entire surface is achieved through contour scanning and dynamic point extraction. The specific process is as follows: S01. Contour Scanning: Before printing, contour scanning equipment such as laser scanning or vision imaging is used to perform a full-range scan of the irregular curved surface object to obtain its three-dimensional contour data, including the perimeter C at different height positions along the axial direction. current The scanned data is transmitted to the control unit 6 to establish a three-dimensional model of the irregular curved surface. S02, Dynamic Calculation of Ink Dot Count: Control Unit 6 extracts the maximum perimeter C from the 3D model. max , with C max As the rotational circumference C, the total number of physical ink dots N is calculated according to step S1; during printing, the axial position information of the current printing cycle is acquired in real time, and the actual circumference C of the corresponding position is obtained from the 3D model. current ; Calculate the required number of ink dots N within the current rotation cycle based on the proportional relationship. current The calculation formula is N current = C current ÷C max ×N.

[0029] S03, Adaptive sampling printing: The control unit 6 maintains the total number of signals output by the encoder 5 in each printing cycle at N, but according to N currentThe difference between N and N generates a sampling strategy; for signal positions that do not require inkjet printing, the corresponding pixel data is set to zero, and the printhead module 3 does not perform inkjet printing when it receives zero data; at the same time, the rotational angular velocity of the curved object is kept constant to ensure that the synchronicity between the moving speed of the printhead 2 and the rotational motion of the curved object is not affected, and finally, the ink droplet distribution in different areas of the irregular curved surface is uniform, ensuring printing consistency. Example

[0030] Printed on the outer surface of a cylindrical fishing rod: Parameter acquisition: The maximum diameter of the fishing rod to be printed is 20mm. According to the formula for the circumference of a circle, its rotational circumference C = π × 20mm ≈ 62.83mm; the printer rotational resolution used in this embodiment is D = 900dpi. Calculation of the total number of physical ink dots: According to the formula N = C÷25.4×D, substitute the data and round up to get N≈2226, that is, the total number of physical ink dots required for the fishing rod to rotate once is 2226. Synchronous configuration: The target pattern is resampled using image processing and pixel matching algorithms to adjust the circumferential pixel width of the image to 2226; the encoder 5 parameters are set to ensure that the total number of position feedback signals output by encoder 5 is 2226 when the fishing rod rotates one revolution. Printing execution: Using Band printing algorithm one, the resampled image is cut into several Band data segments and spliced ​​sequentially before being transmitted to the print buffer; after printing is started, the clamping device 4 drives the fishing rod to rotate at a constant angular velocity, and the print head 2 drives the nozzle module 3 to move at a constant speed along the axis of the fishing rod; for each signal received from the encoder 5, the nozzle 31 sprays an ink dot, finally forming a 360-degree seamless spliced ​​printed pattern on the outer surface of the fishing rod. Example

[0031] Printed on the outer surface of a variable-diameter thermos cup that is narrower at the top and wider at the bottom: Parameter acquisition and contour scanning: The thermos cup to be printed has a variable diameter structure that is narrower at the top and wider at the bottom. Measurements show its maximum diameter is 65mm and its maximum circumference is C. max =π×65mm≈204.2mm; Printer rotation resolution D=900dpi; Laser scanning equipment was used to obtain the complete outer contour data of the thermos cup and establish a 3D model; Calculation of the total number of physical ink dots: According to the formula N = C max ÷25.4×D, substitute the data and round up to get N≈7235, that is, the total number of physical ink dots based on the maximum perimeter is 7235; Synchronous configuration: Resample the target pattern to a circumferential pixel width of 7235; set the total number of output signals per revolution of encoder 5 to 7235; import the 3D model data obtained by contour scanning into control unit 6, and preset the sampling algorithm parameters; Adaptive printing execution: After printing is started, the thermos cup rotates at a constant speed, and the nozzle module 3 moves at a constant speed along the axis of the crossbeam 1. Control unit 6 matches the actual perimeter C of the current printing position in real time. current =153.15mm, calculate the required number of ink dots according to the formula N current =C current ÷C max ×7235=5426, meaning that only 5426 valid ink dots are needed at this position. By using the point sampling algorithm to remove redundant pixel data, 7235-5426=1809 ink dots need to be removed. The point sampling algorithm uses uniform point sampling to avoid image distortion caused by local pixel loss. It is forbidden to sample more than 3 consecutive points to prevent stripe defects. A point sampling mask is generated. The length of the binary mask array is N, which is used to mark which ink dots need to be retained (1) and which need to be removed (0). The generation rules are as follows: Calculate the sampling interval and round down. Sampling interval = floor (7235 ÷ 1809) = 4. Initialize the mask array: all elements are set to 1 by default, meaning all elements are preserved; Mark the removal position by interval: Starting from the first element, select an element at intervals of 1809 and mark the corresponding position as 0 (removed) until the removal quantity = 1809.

[0032] Control unit 6 multiplies the array of pixels to be printed (length = N) bit by bit with the sampling mask array: Pixel data[i] × mask array[i] = filtered data[i]; Reserved bit (mask = 1): Filtered data = original pixel data (printhead normally inkjet); Reject bit (mask = 0): Filtered data = 0 (printhead does not spray ink).

[0033] The control unit 6 sends the filtered pixel data bit by bit to the printhead 31 according to the signal sequence of the encoder 5: Upon receiving non-zero data: printhead 31 ejects the corresponding size / number of ink droplets according to the data instruction; Zero data received: Printhead 31 does not perform inkjet operation; Throughout the process, the encoder 5 maintains a total output signal of N per revolution and a constant rotational angular velocity to ensure printing synchronization, ultimately achieving a uniform and high-precision printing effect on the outer surface of the thermos cup with a variable diameter.

[0034] It should be noted that, in the description of this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joint" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0035] The present invention has been described in detail above. However, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, any modifications or improvements that do not depart from the spirit of the present invention are within the scope of protection of the present invention.

Claims

1. A method for full-circumference inkjet printing on the surface of a curved object, characterized in that, Includes the following steps: S1. Calculation of the total number of physical ink dots: Obtain the rotational circumference of the curved object and the resolution of the printer in the rotational direction. Calculate the total number of physical ink dots required for the curved object to rotate one revolution using the formula N = (C÷25.4) × D, and round up. Where C is the rotational circumference in mm; D is the resolution in dpi; and N is the total number of physical ink dots. S2. Pattern pixel matching: The printing software processes the circumferential image data of the target pattern so that the total number of pixels required for the pattern to circle the curved object is equal to the total number of physical ink dots. S3. Encoder configuration: Set an external encoder so that when the curved object rotates one revolution, the total number of signals output by the encoder is equal to the total number of physical ink dots; S4. Collaborative Printing Control: The curved object rotates continuously and uniformly around its own axis, triggering the printhead to eject ink dots one by one according to the signal output by the encoder, while controlling the printhead to move uniformly in a direction parallel to the axis of the curved object.

2. The method for full-circumference inkjet printing of a curved object surface according to claim 1, characterized in that, It also includes an adaptive printing step for irregularly shaped curved objects: S01. Contour Scan: Before printing, perform a full-range contour scan on the irregular curved surface object to obtain its three-dimensional data of the outer contour and extract the maximum rotational circumference C. max and the actual circumference C at different positions along the axis current ; S02. Dynamic calculation of ink dot count: Based on the ratio of the maximum rotation circumference to the actual rotation circumference at the current position, according to formula N... current =C current ÷C max ×N, dynamically adjusts the number of physical ink dots N in the current rotation cycle. current ; S03, Adaptive Spot Printing: Keeps the total number of encoder output signals constant in each rotation cycle of the object, sets the pixel data corresponding to the excess ink dots in the current rotation cycle to zero, and does not perform inkjet action when the printhead receives zero data, thus realizing spot printing.

3. The method for full-circumference inkjet printing on a curved object surface according to claim 1, characterized in that, The circumferential image data processing in S2 includes image resampling and pixel-physical position mapping. Specifically, it receives the original pattern file and parses it into a digital image matrix. The target pixel width is set to the total number of physical ink dots. When the original image width is not equal to the target pixel width, an interpolation algorithm is used to resample the original image to adjust the image width to the target pixel width. A one-to-one correspondence is established between the image pixel index and the physical position on the surface of the curved object.

4. The method for full-circumference inkjet printing of a curved object surface according to claim 1, characterized in that, The printing software uses a band printing algorithm to cut the processed pattern into several band data segments at a constant step height, and then splices them sequentially or in segments for printing.

5. The method for full-circumference inkjet printing of a curved object surface according to claim 4, characterized in that, The implementation of the Band printing algorithm includes: The processed pattern is cut into multiple band data segments along a direction perpendicular to the rotation direction; The data segments of each band are concatenated into a continuous data stream and sent to the printhead in sequence for printing.

6. The method for full-circumference inkjet printing of a curved object surface according to claim 4, characterized in that, The implementation of the Band printing algorithm includes: The processed pattern is cut into multiple band data segments; Print the data segments in the order of the Bands, and stitch adjacent data segments together in real time according to the rotation angle of the curved object and the movement position of the nozzle.

7. The method for full-circumference inkjet printing of a curved object surface according to claim 4, characterized in that, The step height is calculated and determined by the printing algorithm based on the printer's resolution and pattern size in the stepping direction.

8. The method for full-circumference inkjet printing of a curved object surface according to claim 3, characterized in that, The interpolation algorithm includes bilinear interpolation, bicubic interpolation, or the Lanczos resampling algorithm.

9. A full-circumference inkjet printing device for curved object surfaces, characterized in that, include: Clamping device: used to fix curved objects and drive the curved objects to rotate continuously and uniformly around their own axis; Nozzle module: includes at least one nozzle, and the spray direction of all nozzles is parallel to the axis of the curved object; Crossbeam: Extends along the axial direction of the curved object; The nozzle head is slidably mounted on the crossbeam and can move at a constant speed along the crossbeam. The nozzle module is fixedly mounted on the nozzle head. Encoder: Linked with the clamping device, used to emit position feedback signals when the curved object rotates; Control unit: electrically connected to the clamping device, printhead module, printhead and encoder respectively, for performing the full-circumference inkjet printing method for curved object surface as described in any one of claims 1 to 8.

10. A computer-readable storage medium storing a computer program, characterized in that, When the program is executed by the processor, it implements a full-circumference inkjet printing method for curved object surfaces as described in any one of claims 1 to 8.

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