A 3D printing method, system, device and storage medium for a target object

Abstract

The present invention relates to the field of image data processing technology, and specifically to a 3D printing method, system, device and storage medium for a target object. The 3D printing method processes a three-dimensional image of a target object in layers and designs a printing path sequence for each layer. After each layer is printed, the height difference, horizontal dimension difference and printing void area are inspected in sequence according to the currently printed three-dimensional image of the physical object and the point cloud data of the corresponding single-layer three-dimensional image of the target object. Based on the inspection results, timely feedback and adjustment are performed, which not only improves the professionalism, stability and efficiency of printing, but also improves the similarity between the printed physical object and the target object, thereby achieving more accurate 3D printing.

Description

Technical Field

[0001] The present invention relates to the technical field of image data processing, and in particular to a 3D printing method, system, device and storage medium for a target object. Background Art

[0002] With the development of 3D printing technology, many aspects of people's daily lives are changing. For example, the medical community widely uses 3D printing technology to manufacture customized prostheses, artificial limbs, and medical devices. This technology can improve the quality of life of patients, reduce surgical risks, and reduce medical costs. In addition, the use of 3D printing technology has great significance in improving the quality of life, promoting innovation, reducing costs, and solving various problems in a different way.

[0003] Common 3D printing targets include prototype parts made of plastic materials, aircraft engine components, medical prostheses, bionic organs, and customized foods. Slicing software is usually used to slice the standard subdivision language (Stereolithography, STL) files or CAD source files of the three-dimensional models of these targets, and then convert them into G-code files (or paths) suitable for 3D printers. If the structure of the model is too complex, mathematical equations can be used to generate the model file, and then slice and print it.

[0004] In real-time feedback of 3D printing, the next printing plan is often decided by manually inspecting the printed object to find visible defects, such as poor interlayer adhesion, cracks, loss of melting, faults or poor appearance. However, this method requires professionals to actively identify, and has low stability and professionalism. In addition, 3D printers usually have sensors and monitoring systems to monitor temperature, nozzle status, printing speed and interlayer adhesion. These systems can perform real-time detection and feedback, but this method is to infer the problems in the printing process based on the status of the printer. The theoretical error and the actual error are quite different, resulting in a low similarity between the printed object and the target object. Summary of the invention

[0005] The object of the present invention is to provide a 3D printing method, system, device and storage medium for a target object.

[0006] The technical solution of the present invention is as follows:

[0007] A 3D printing method for a target object includes the following operations:

[0008] S1. Obtain a three-dimensional image of the target object, and based on the three-dimensional image of the target object, obtain a printing planning path sequence and a multi-layer three-dimensional image of the target object;

[0009] S2, after completing the printing of the current layer according to the current layer printing path sequence in the printing planning path sequence, obtaining the height difference between the current layer printed physical object three-dimensional image and the corresponding single-layer three-dimensional image of the target object, and judging whether the height difference exceeds a first threshold; if so, stop printing; if not, execute S3;

[0010] S3, obtaining the horizontal dimension difference between the three-dimensional image of the current layer and the corresponding single-layer three-dimensional image of the target object; determining whether the horizontal dimension difference exceeds a second threshold; if so, stopping printing; if not, executing S4;

[0011] S4, obtaining a difference image between the three-dimensional image of the current layer of printed physical object and the three-dimensional image of the corresponding single layer of the target object, and judging whether there is a printing hole area based on the difference image; if not, executing S2; if yes, executing S5;

[0012] S5, acquiring the hole plane position data of the printing hole area, adjusting the next layer printing path sequence based on the hole plane position data, and then executing S2;

[0013] When the number of times S2 is executed is equal to the number of layers of the multi-layer three-dimensional image of the target object, a 3D printed object is obtained.

[0014] The operation of obtaining the printing planning path sequence in S1 is specifically as follows:

[0015] Step 1: acquiring point cloud data of the three-dimensional image of the target object, and obtaining multi-layer point cloud data through layered processing;

[0016] Step 2: Based on the preset printing line width and the preset printing coordinate origin, the current layer point cloud data is partitioned to obtain a multi-region point cloud data set of the current layer;

[0017] Step 3: Based on the preset single-layer printing direction, the multi-region point cloud data of the current layer are concentrated, and all the single-region point cloud data are connected to obtain an initial printing path sequence;

[0018] Step 4: Preset a sliding window. When the sliding window traverses the initial printing path sequence, the average value of the point cloud data in the sliding window in the Z-axis direction is used as the printing height, and after combining it with the initial printing path sequence, a current layer printing path sequence is obtained;

[0019] In the multi-layer point cloud data, after all single-layer point cloud data execute the operations of step two, step three and step four, all single-layer printing path sequences obtained form a multi-layer printing path sequence; based on the preset multi-layer printing path order, all single-layer printing path sequences are connected to obtain the printing planning path sequence.

[0020] Before the layered processing operation, the point cloud data of the three-dimensional image of the target object is also subjected to flipping and downsampling processing.

[0021] The horizontal dimension difference in S3 is: the maximum value in the X-axis direction, and / or the minimum value in the X-axis direction, and / or the maximum value in the Y-axis direction, and / or the minimum value in the Y-axis direction after the three-dimensional image of the current layer of the printed physical object is projected onto the two-dimensional plane, and the difference between the maximum value in the X-axis direction, and / or the minimum value in the X-axis direction, and / or the maximum value in the Y-axis direction, and / or the minimum value in the Y-axis direction of the corresponding single-layer three-dimensional image of the target object after being projected onto the two-dimensional plane.

[0022] The operation of judging whether there is a printing hole area based on the difference image in S4 is specifically as follows: obtaining a difference image between a three-dimensional image of the current layer of the printed object after being projected onto a two-dimensional plane and a three-dimensional image of a corresponding single layer of the target object after being projected onto a two-dimensional plane, and judging whether an area with a pixel mean value greater than a third threshold value appears in the difference image; if so, the corresponding area is the printing hole area; if not, the printing hole area does not exist.

[0023] The operation of adjusting the next layer printing path sequence based on the hole plane position data in S5 is specifically as follows:

[0024] After the printing height at the position corresponding to the hole plane position data in the next layer printing path sequence is updated to the sum of the initial printing height in the next layer printing path sequence and the previous layer printing height, the next layer printing is performed.

[0025] The operation of obtaining the three-dimensional image of the printed object at the current layer in S2 is specifically as follows:

[0026] Acquire an image of the current layer of printed objects to obtain a current layer of printed objects map; acquire a height data set of the current layer of printed objects map, combine the height data set with an edge contour map of the current layer of printed objects map at corresponding positions, and obtain a three-dimensional map of the current layer of printed objects map.

[0027] A 3D printing system for a target object, comprising:

[0028] A printing planning path sequence and a target object multi-layer three-dimensional image generation module is used to obtain a target object three-dimensional image, and obtain a printing planning path sequence and a target object multi-layer three-dimensional image based on the target object three-dimensional image;

[0029] A height difference judgment module is used to obtain the height difference between the three-dimensional image of the current layer printed object and the corresponding single-layer three-dimensional image of the target object after the current layer printing is completed according to the current layer printing path sequence in the printing planning path sequence, and judge whether the height difference exceeds a first threshold; if it exceeds, stop printing; if it does not exceed, execute the horizontal dimension difference judgment module;

[0030] A horizontal dimension difference judgment module is used to obtain the horizontal dimension difference between the current layer printed physical object three-dimensional image and the corresponding single-layer three-dimensional image of the target object; judge whether the horizontal dimension difference exceeds a second threshold; if so, stop printing; if not, execute the printing hole area judgment module;

[0031] A printing hole area judgment module is used to obtain a difference image between the three-dimensional image of the current layer of printed physical object and the three-dimensional image of the corresponding single layer of the target object, and judge whether there is a printing hole area based on the difference image; if not, execute the height difference judgment module; if so, execute the printing path sequence adjustment module;

[0032] A printing path sequence adjustment module, used for acquiring the hole plane position data of the printing hole area, adjusting the next layer of printing path sequence based on the hole plane position data, and then executing the height difference judgment module;

[0033] When the height difference judgment module is executed for a number of times equal to the number of layers of the multi-layer three-dimensional image of the target object, a 3D printed object is obtained.

[0034] A 3D printing device for a target object comprises a processor and a memory, wherein the processor implements the above-mentioned 3D printing method for the target object when executing a computer program stored in the memory.

[0035] A computer-readable storage medium is used to store a computer program, wherein the computer program implements the above-mentioned 3D printing method of the target object when executed by a processor.

[0036] The beneficial effects of the present invention are:

[0037] The present invention provides a 3D printing method for a target object, which processes the three-dimensional image of the target object in layers and designs a printing path sequence for each layer. After each layer is printed, the height difference, horizontal dimension difference and printing void area are inspected in sequence according to the currently printed three-dimensional image of the actual object and the point cloud data of the corresponding single-layer three-dimensional image of the target object, and timely feedback and adjustment are performed based on the inspection results, which not only improves the professionalism, stability and efficiency of printing, but also improves the similarity between the printed actual object and the target object, thereby achieving more accurate 3D printing. DETAILED DESCRIPTION

[0038] This embodiment provides a 3D printing method for a target object, including the following operations:

[0039] S1. Obtain a three-dimensional image of the target object, and based on the three-dimensional image of the target object, obtain a printing planning path sequence and a multi-layer three-dimensional image of the target object;

[0040] S2, after completing the printing of the current layer according to the current layer printing path sequence in the printing planning path sequence, obtaining the height difference between the current layer printed physical object three-dimensional image and the corresponding single-layer three-dimensional image of the target object, and judging whether the height difference exceeds a first threshold; if so, stop printing; if not, execute S3;

[0041] S3, obtaining the horizontal dimension difference between the three-dimensional image of the current layer and the corresponding single-layer three-dimensional image of the target object; determining whether the horizontal dimension difference exceeds a second threshold; if so, stopping printing; if not, executing S4;

[0042] S4, obtaining a difference image between the three-dimensional image of the current layer of printed physical object and the three-dimensional image of the corresponding single layer of the target object, and judging whether there is a printing hole area based on the difference image; if not, executing S2; if yes, executing S5;

[0043] S5, acquiring the hole plane position data of the printing hole area, adjusting the next layer printing path sequence based on the hole plane position data, and then executing S2;

[0044] When the number of times S2 is executed is equal to the number of layers of the multi-layer three-dimensional map of the target object, a 3D printed object is obtained. S1. Obtain a three-dimensional map of the target object, and obtain a printing planning path sequence and a multi-layer three-dimensional map of the target object based on the three-dimensional map of the target object.

[0045] Get a 3D image of the target object. Use a 3D scanner to scan the target object, build a 3D model with spatial position information, and save it in the form of a point cloud to get a 3D image of the target object.

[0046] Get a multi-layer 3D image of the target object. Set the number of prints and the corresponding layer height for each print according to the print line width (determined by the pinhole diameter of the printer and the speed at which the raw material is ejected from the pinhole) and the height of the target object. According to the print layer height for each print, the 3D image of the target object is horizontally cut into multiple single-layer 3D images of the target object to be printed stacked up and down to obtain a multi-layer 3D image of the target object.

[0047] The operation of obtaining the printing planning path sequence is as follows: step 1, obtaining the point cloud data of the three-dimensional image of the target object, and obtaining multi-layer point cloud data through layered processing; step 2, partitioning the point cloud data of the current layer based on the preset printing line width and the preset printing coordinate origin to obtain the multi-region point cloud data set of the current layer; step 3, based on the preset single-layer printing direction, the multi-region point cloud data set of the current layer is concentrated, and all single-region point cloud data are connected to obtain the initial printing path sequence; step 4, a preset sliding window is set, and when the sliding window traverses the initial printing path sequence, the average value of the point cloud data in the sliding window in the Z-axis direction is used as the printing height, and after combining with the initial printing path sequence, the current layer printing path sequence is obtained; in the multi-layer point cloud data, after all single-layer point cloud data execute the operations of step 2, step 3 and step 4, all single-layer printing path sequences obtained form a multi-layer printing path sequence; based on the preset multi-layer printing path order, all single-layer printing path sequences are connected to obtain the printing planning path sequence. Before the layered processing operation, the point cloud data of the three-dimensional image of the target object is also flipped and downsampled.

[0048] Specifically, the point cloud data of the three-dimensional image of the target object is obtained, and the image is flipped and then downsampled to reduce the point cloud density and improve the computing efficiency. The downsampled point cloud data is layered in the horizontal direction to obtain multi-layer point cloud data; the printing coordinate origin is preset, and the current layer of point cloud data is cut and partitioned along the X-axis direction to obtain multiple strips of single-area point cloud data to form a current layer of multi-area point cloud data set. In the current layer of multi-area point cloud data set, the position width of each single-area point cloud data is equal to the printing line width; then, according to the preset single-layer printing direction, for example, printing along the positive direction of the X-axis - printing along the negative direction of the X-axis - printing along the positive direction of the X-axis, all the single-area point cloud data in the current layer of multi-area point cloud data set are printed and sorted, and the tail of the previous single-area point cloud data is connected to the head of the next single-area point cloud data, and so on. After serial connection, a complete single-area point cloud data on the X-axis and the Y-axis can be formed. The initial printing path sequence of the layer is then preset, and the sliding window is preset, with a width equal to the printing line width and a height that can be designed according to the current printing layer height. The sliding window is used to traverse the initial printing path sequence, and the average value of all point cloud data in the sliding window in the Z-axis direction (i.e., the height data in the point cloud data) is used as the height position of the printer's needle when printing, i.e., the printing height, which can control the thickness of the printing material at this plane position, and is combined with the single-layer initial printing path sequence on the X-axis and Y-axis to form the current layer printing path sequence; further, from bottom to top, after all single-layer point cloud data execute the operations of step two, step three, and step four, all single-layer printing path sequences obtained form a multi-layer printing path sequence; finally, a multi-layer printing path sequence is preset, and the tail of the previous single-layer printing path sequence is connected to the head of the next single-layer printing path sequence front and back, and so on, after serial connection, a printing planning path sequence is obtained.

[0049] In addition, if there is no printing height data in a position sequence in the print planning path sequence, then the position sequence does not require printing points, the printing status of the position sequence is set to closed, and the position height of the printing needle at this position is increased so that it can pass through the area safely without touching the printed object.

[0050] According to the actual location requirements of the printed object, the position coordinates of the point cloud data in the print planning path sequence can be corrected to unify them with the coordinate system of the printer, so as to facilitate accurate and fast 3D printing. S2. According to the current layer print path sequence in the print planning path sequence, after the current layer prints, obtain the height difference between the current layer print object 3D image and the corresponding single layer 3D image of the target object, and determine whether the height difference exceeds the first threshold; if it exceeds, stop printing; if it does not exceed, execute S3;

[0051] The operation of obtaining the three-dimensional image of the current printed object is as follows: obtaining the image of the current printed object to obtain the current printed object image; obtaining the height data set of the current printed object image, combining the height data set with the edge contour map of the current printed object image at the corresponding position to obtain the current printed object three-dimensional image. Specifically, obtaining an image of a circle of the current printed object, and using the projective geometry analysis method (common prior art) to obtain a circle of height data of the current printed object, to obtain the height data set; then, using the Sobel operator (common prior art) to obtain the edge contour map of the current printed object, combining the height data set with the edge contour at the corresponding position to obtain the current printed object three-dimensional image.

[0052] The operation of obtaining the height difference is as follows: obtaining the absolute value of the difference between the height data of each position in the current layer printed three-dimensional image and the corresponding single-layer three-dimensional image of the target object to obtain the height difference; judging whether the height difference exceeds 10% of the current layer printing height; if so, it is considered that the height difference is too large and printing is stopped at this time; if not, the operation in S3 can be executed.

[0053] S3, obtaining the horizontal dimension difference between the current layer printed physical object three-dimensional image and the corresponding single-layer three-dimensional image of the target object; determining whether the horizontal dimension difference exceeds a second threshold; if so, stopping printing; if not, executing S4.

[0054] The horizontal dimension difference is the difference between the maximum value in the X-axis direction, and / or the minimum value in the X-axis direction, and / or the maximum value in the Y-axis direction, and / or the minimum value in the Y-axis direction after the current layer of the printed physical object three-dimensional image is projected onto the two-dimensional plane, and the maximum value in the X-axis direction, and / or the minimum value in the X-axis direction, and / or the maximum value in the Y-axis direction, and / or the minimum value in the Y-axis direction of the corresponding single-layer three-dimensional image of the target object after being projected onto the two-dimensional plane.

[0055] The horizontal dimension difference can be exemplified as follows: the horizontal dimension difference includes the absolute value of the difference between the maximum value in the X-axis direction of the current layer of the printed physical object three-dimensional image after being projected onto the two-dimensional plane and the maximum value in the X-axis direction of the corresponding single-layer three-dimensional image of the target object after being projected onto the two-dimensional plane, which is recorded as the first horizontal dimension difference; the absolute value of the difference between the minimum value in the X-axis direction and the minimum value in the X-axis direction of the corresponding single-layer three-dimensional image of the target object after being projected onto the two-dimensional plane, which is recorded as the second horizontal dimension difference; the absolute value of the difference between the maximum value in the Y-axis direction and the maximum value in the Y-axis direction of the corresponding single-layer three-dimensional image of the target object after being projected onto the two-dimensional plane, which is recorded as the third horizontal dimension difference; the absolute value of the difference between the minimum value in the Y-axis direction and the minimum value in the Y-axis direction of the corresponding single-layer three-dimensional image of the target object after being projected onto the two-dimensional plane, which is recorded as the fourth horizontal dimension difference; if any one of the first horizontal dimension difference, the second horizontal dimension difference, the third horizontal dimension difference, and the fourth horizontal dimension difference exceeds 20% of the print line width, it proves that the horizontal dimension difference is too large and printing should be stopped; if all of them exceed 20% of the print line width, the operation in S4 can be executed.

[0056] S4, obtaining a difference image between the current layer printed object 3D image and the corresponding single layer 3D image of the target object, and judging whether there is a printing hole area based on the difference image; if not, executing S2; if yes, executing S5.

[0057] Based on the difference image, the operation of judging whether there is a printing hole area is as follows: obtaining the three-dimensional image of the current layer of the printed object after being projected onto the two-dimensional plane, and the difference image between the three-dimensional image of the corresponding single-layer of the target object after being projected onto the two-dimensional plane, and judging whether there is an area in the difference image whose pixel mean is greater than the third threshold; if so, the corresponding area is a printing hole area; if not, there is no printing hole area.

[0058] Specifically, after projecting the point cloud data in the current layer of printed physical object three-dimensional image onto a two-dimensional plane, a current layer of printed physical object plane image is obtained; after projecting the corresponding single-layer three-dimensional image of the target object onto a two-dimensional plane, a single-layer plane image of the target object is obtained; the current layer of printed physical object plane image and the single-layer plane image of the target object are aligned to obtain a difference image; determine whether an area with a pixel mean value greater than a third threshold (preset pixel threshold) appears on the difference image; if so, it proves that the coordinate point data of the area at the corresponding positions on the current layer of printed physical object plane image and the single-layer plane image of the target object are inconsistent, proving that an error occurred in the printing process, and the area is a printing hole area, and the operation of S5 should be executed; if not, it proves that the printing process is normal, and the next layer of printing is performed, and S2 is executed.

[0059] S5, obtaining the hole plane position data of the printing hole area, adjusting the next layer printing path sequence based on the hole plane position data, and then executing S2.

[0060] Based on the hole plane position data, the operation of adjusting the next layer of printing path sequence is: updating the printing height at the position corresponding to the hole plane position data in the next layer of printing path sequence to the sum of the initial height in the next layer of printing path sequence and the height of the previous layer of printing, and then executing the next layer of printing.

[0061] Specifically, after a printing hole area is found, the coordinate data of the X-axis and Y-axis of the printing hole area in the three-dimensional image of the physical object printed in the current layer are obtained to obtain the hole plane position data; then, the printing height at the X-axis and Y-axis coordinates that are the same as the hole plane position data in the next layer printing path sequence is updated to the sum of the initial printing height in the original next layer printing path sequence and the previous layer printing layer height to fill the printing hole of the previous layer, and finally, the printing of the next layer is executed, and S2 is executed.

[0062] When the number of times S2 is executed is equal to the number of layers of the multi-layer three-dimensional image of the target object, a 3D printed object is obtained.

[0063] This embodiment also provides a 3D printing system for a target object, including:

[0064] A printing planning path sequence and a target multi-layer three-dimensional image generation module is used to obtain a target three-dimensional image, and obtain a printing planning path sequence and a target multi-layer three-dimensional image based on the target three-dimensional image;

[0065] A height difference judgment module is used to obtain the height difference between the three-dimensional image of the current layer and the corresponding single-layer three-dimensional image of the target object after the current layer is printed according to the current layer printing path sequence in the printing planning path sequence, and judge whether the height difference exceeds the first threshold; if it exceeds, stop printing; if it does not exceed, execute the horizontal dimension difference judgment module;

[0066] A horizontal dimension difference judgment module is used to obtain the horizontal dimension difference between the current layer printed physical object three-dimensional image and the corresponding single-layer three-dimensional image of the target object; judge whether the horizontal dimension difference exceeds a second threshold; if so, stop printing; if not, execute the printing hole area judgment module;

[0067] The printing hole area judgment module is used to obtain the difference image between the current layer printed physical object three-dimensional image and the corresponding single-layer three-dimensional image of the target object, and judge whether there is a printing hole area based on the difference image; if not, execute the height difference judgment module; if so, execute the printing path sequence adjustment module;

[0068] A printing path sequence adjustment module is used to obtain the hole plane position data of the printing hole area, adjust the next layer of printing path sequence based on the hole plane position data, and then execute the height difference judgment module;

[0069] When the height difference judgment module is executed for a number of times equal to the number of layers of the multi-layer three-dimensional image of the target object, a 3D printed object is obtained.

[0070] This embodiment further provides a 3D printing device for a target object, including a processor and a memory, wherein the processor implements the above-mentioned 3D printing method for the target object when executing a computer program stored in the memory.

[0071] This embodiment further provides a computer-readable storage medium for storing a computer program, wherein the computer program implements the above-mentioned 3D printing method of the target object when executed by a processor.

[0072] The present embodiment provides a 3D printing method for a target object, which processes the three-dimensional image of the target object in layers and designs a printing path sequence for each layer. After each layer is printed, the height difference, horizontal dimension difference and printing void area are inspected in sequence according to the currently printed three-dimensional image of the actual object and the point cloud data of the corresponding single-layer three-dimensional image of the target object. Based on the inspection results, timely feedback and adjustments are made, which not only improves the professionalism, stability and efficiency of printing, but also improves the similarity between the printed actual object and the target object, thereby achieving more accurate 3D printing.

Claims

1. A 3D printing method for a target object, characterized in that: The following operations are included: S1. Obtain a three-dimensional image of the target object, and based on the three-dimensional image of the target object, obtain a printing plan path sequence and a multi-layer three-dimensional image of the target object; the operation of obtaining the printing plan path sequence is specifically as follows: Step 1: Obtain point cloud data of the three-dimensional image of the target object, and obtain multi-layer point cloud data through layered processing; Step 2: Partition the current layer point cloud data based on a preset printing line width and a preset printing coordinate origin to obtain a multi-region point cloud data set of the current layer; Step 3: Based on a preset single-layer printing direction, concentrate the multi-region point cloud data set of the current layer, and connect all single-region point cloud data to obtain an initial printing path sequence; Step 4: Preset a sliding window, and when the sliding window traverses the initial printing path sequence, use the average value of the point cloud data in the sliding window in the Z-axis direction as the printing height, and combine it with the initial printing path sequence to obtain the current layer printing path sequence; in the multi-layer point cloud data, after executing the operations of Step 2, Step 3 and Step 4 on all single-layer point cloud data, all single-layer printing path sequences obtained form a multi-layer printing path sequence; Based on a preset multi-layer printing path order, all single-layer printing path sequences are connected to obtain the printing plan path sequence; S2. After completing printing of the current layer according to the printing path sequence of the current layer in the printing plan path sequence, obtaining a height difference between the three-dimensional image of the current layer and the three-dimensional image of the corresponding single layer of the target object, and determining whether the height difference exceeds a first threshold; If exceeded, stop printing; If not, execute S3; S3, obtaining a horizontal dimension difference between the three-dimensional image of the current layer of printed physical object and the three-dimensional image of the corresponding single layer of the target object; and determining whether the horizontal dimension difference exceeds a second threshold; If exceeded, stop printing; If not exceeded, execute S4; S4, obtaining a difference image between the three-dimensional image of the current layer of printed physical object and the three-dimensional image of the corresponding single layer of the target object, and determining whether there is a printing void area based on the difference image; If it does not exist, execute S2; if it does exist, execute S5; S5, obtaining the hole plane position data of the printing hole area, adjusting the next layer printing path sequence based on the hole plane position data, and then executing S2; When the number of times S2 is executed is equal to the number of layers of the multi-layer three-dimensional image of the target object, a 3D printed object is obtained.

2. The 3D printing method of the target object according to claim 1, characterized in that: Before the layered processing operation, the point cloud data of the three-dimensional image of the target object is also subjected to flipping and downsampling processing.

3. The 3D printing method of the target object according to claim 1, characterized in that: The horizontal dimension difference in S3 is: the difference between the maximum value in the X-axis direction, and / or the minimum value in the X-axis direction, and / or the maximum value in the Y-axis direction, and / or the minimum value in the Y-axis direction of the current layer of the printed physical object three-dimensional image after being projected onto the two-dimensional plane, and the maximum value in the X-axis direction, and / or the minimum value in the X-axis direction, and / or the maximum value in the Y-axis direction, and / or the minimum value in the Y-axis direction of the corresponding single-layer three-dimensional image of the target object after being projected onto the two-dimensional plane.

4. The 3D printing method of the target object according to claim 1, characterized in that: The operation of determining whether there is a print hole area based on the difference map in S4 is specifically as follows: Obtaining a difference image between a three-dimensional image of the current layer of the printed object projected onto a two-dimensional plane and a three-dimensional image of a corresponding single layer of the target object projected onto the two-dimensional plane, and determining whether an area with a pixel mean greater than a third threshold value appears in the difference image; If it appears, the corresponding area is the printing hole area; If not, the print hole area does not exist.

5. The 3D printing method of the target object according to claim 1, characterized in that: The operation of adjusting the next layer printing path sequence based on the hole plane position data in S5 is specifically as follows: After updating the printing height at the position corresponding to the hole plane position data in the next layer printing path sequence to the sum of the initial printing height in the next layer printing path sequence and the previous layer printing height, the next layer printing is performed.

6. The 3D printing method of the target object according to claim 1, characterized in that: The operation of obtaining the three-dimensional image of the printed object at the current layer in S2 is specifically as follows: Acquire an image of the printed object on the current layer to obtain a map of the printed object on the current layer; obtain a height data set of the map of the printed object on the current layer, combine the height data set with the edge contour map of the printed object on the current layer at corresponding positions, and obtain a three-dimensional map of the printed object on the current layer.

7. A 3D printing system for a target object, characterized in that: include: A printing planning path sequence and target object multi-layer 3D image generation module is used to obtain a target object 3D image and obtain a printing planning path sequence and a target object multi-layer 3D image based on the target object 3D image; The operation of obtaining the printing planning path sequence is specifically as follows: step 1, obtaining the point cloud data of the three-dimensional image of the target object, and obtaining multi-layer point cloud data through layered processing; step 2, partitioning the current layer point cloud data based on the preset printing line width and the preset printing coordinate origin to obtain the current layer multi-region point cloud data set; step 3, based on the preset single-layer printing direction, the current layer multi-region point cloud data set is concentrated, and all single-region point cloud data are connected to obtain the initial printing path sequence; step 4, a sliding window is preset, and when the sliding window traverses the initial printing path sequence, the average value of the point cloud data in the sliding window in the Z-axis direction is used as the printing height, and after combining it with the initial printing path sequence, the current layer printing path sequence is obtained; in the multi-layer point cloud data, all single-layer point cloud data after executing the operations of step 2, step 3 and step 4 form a multi-layer printing path sequence; based on the preset multi-layer printing path order, all single-layer printing path sequences are connected to obtain the printing planning path sequence; a height difference judgment module, configured to obtain, based on the current layer printing path sequence in the printing plan path sequence, a height difference between the three-dimensional image of the current layer printed physical object and the corresponding single-layer three-dimensional image of the target object after the current layer printing is completed, and determine whether the height difference exceeds a first threshold; If exceeded, stop printing; If not, execute the horizontal dimension difference judgment module; a horizontal dimension difference determination module, configured to obtain a horizontal dimension difference between the three-dimensional image of the current layer of printed physical object and the three-dimensional image of the corresponding single layer of the target object; and determine whether the horizontal dimension difference exceeds a second threshold; If exceeded, stop printing; If it does not exceed the limit, the print hole area judgment module is executed; a print void region determination module, configured to obtain a difference image between the three-dimensional image of the current layer of printed physical object and the three-dimensional image of the corresponding single layer of the target object, and determine whether a print void region exists based on the difference image; If not, executing the height difference judgment module; If it exists, execute the printing path sequence adjustment module; a printing path sequence adjustment module, configured to obtain the hole plane position data of the printing hole area, adjust the next layer's printing path sequence based on the hole plane position data, and then execute the height difference judgment module; When the height difference judgment module is executed for a number of times equal to the number of layers of the multi-layer three-dimensional image of the target object, a 3D printed object is obtained.

8. A 3D printing device for a target object, characterized in that: The method comprises a processor and a memory, wherein when the processor executes the computer program stored in the memory, the method for 3D printing of the target object according to any one of claims 1 to 6 is implemented.

9. A computer-readable storage medium, characterized in that Used to store a computer program, wherein when the computer program is executed by a processor, the 3D printing method of the target object according to any one of claims 1 to 6 is implemented.