An efficient multi-color printing system control method suitable for 3D printing

Abstract

The present invention belongs to the field of 3D printing technology, and specifically relates to an efficient multi-color printing system control method suitable for 3D printing, comprising obtaining three-dimensional model data containing multiple color information, dividing the data into multiple slices, and pre-loading pigment into the print head according to the color distribution of each slice. During the printing process, the color distribution consistency is monitored in real time, and the position of the print head and the amount of pigment are adjusted when a color deviation is detected. After completing the printing of one slice, the pigment loading scheme is updated according to the adjustment result until all slices are printed. Finally, the color reproduction quality is evaluated by comparing the finished product with the original data. This method significantly improves printing efficiency, enhances the naturalness of color transitions, and improves color reproduction, thereby significantly improving the overall performance of multi-color 3D printing.

Description

Technical Field

[0001] The present invention belongs to the technical field of 3D printing, and in particular relates to a high-efficiency multi-color printing system control method suitable for 3D printing. Background Art

[0002] With the advancement of 3D printing technology, users are demanding increasingly higher colors for their printed products. Traditional monochrome 3D printing can no longer meet these increasingly complex color requirements. While some multi-color 3D printing systems currently on the market can achieve basic multi-color printing capabilities, they still face some practical challenges, such as inefficient color changes, unnatural color transitions, and poor color reproduction.

[0003] Existing multi-color 3D printing solutions typically utilize multiple printheads or multiple materials to achieve printing in different colors. While this approach can address the limitations of monochrome printing to some extent, it requires significant time for cleaning and switching between colors, resulting in slower printing speeds. Furthermore, inadequate color boundary processing can lead to abrupt color transitions, impacting visual quality. Finally, due to a lack of effective color management, the actual printed colors deviate somewhat from the designed colors, resulting in poor color reproduction. Summary of the Invention

[0004] The purpose of the present invention is to provide an efficient multi-color printing system control method suitable for 3D printing, which improves printing efficiency and color reproduction by optimizing color management and real-time monitoring of color deviation, so as to solve the problems raised in the above background technology.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a high-efficiency multi-color printing system control method suitable for 3D printing, comprising the following steps:

[0006] S1: Acquire three-dimensional model data containing multiple color information; S2: Divide the data in S1 into multiple slices to be printed in layers, each slice containing color distribution information; S3: Before starting printing, pre-load the corresponding pigment into the print head according to the color distribution of each slice in S2; S4: Control the print head to apply the corresponding color material at the correct position according to the pigment loaded in S3; S5: During the printing process of S4, monitor in real time the consistency between the area where the pigment has been applied and the predefined color distribution in S2; S6: When color deviation is detected in S5, adjust the position and amount of pigment applied by the print head in S4; S7: After completing the printing of a slice, update the pigment loading plan in S3 according to the adjustment result in S6 and the color distribution of the next slice in S2; S8: After the update of S7, continue to execute the operations of S4 to S6 until all slices are printed; S9: After the printing process is completed, evaluate the overall color reproduction quality by comparing the final product with the original data in S1.

[0007] Preferably, in S1, the following steps are included:

[0008] Read the 3D model file and extract the color value of each vertex on the model surface; based on the extracted color values, calculate the color difference coefficient ΔCij=|Ci-Cj| between adjacent vertices, where Ci and Cj represent the color values ​​of two adjacent vertices respectively; based on the color difference coefficient ΔCij, determine the color gradient path so that the transition between adjacent colors is smooth; apply the determined color gradient path to color the model slices to ensure natural color transition during printing.

[0009] Preferably, in S2, the following steps are included:

[0010] The 3D model data in S1 is sliced ​​layer by layer to form a series of parallel and equidistant 2D slices. The color density distribution of each slice is calculated, which is defined as the number of color types per unit area Nc. The color density distribution Nc is used to adjust the color mixing ratio of each area in the corresponding slice to ensure a natural color transition between adjacent areas. Based on the color mixing ratio, a corresponding printing instruction set is generated for each slice to accurately control the distribution of each color material during the actual printing process.

[0011] Preferably, in S3, the following steps are included:

[0012] First, determine the color distribution characteristics of the slice, and record the different types of pigments required for each layer and the estimated usage. Based on the color types and usage, calculate the pigment preload amount Pv, where Pv is equal to the sum of the required amounts of each color multiplied by the preset loading coefficient α (Pv=Σusagei*α). Before starting printing, load the corresponding pigment into the storage container of the print head according to the value of the pigment preload amount Pv, and then prepare the pigment required for the next slice in advance according to the actual printing order.

[0013] Preferably, in S4, the following steps are included:

[0014] According to the pigment loading situation in S3, the movement path of the print head is planned and the color output intensity Ci of each coordinate point on the path is set; during the printing process, the color error E=|Ci-C(i-1)| at the current position of the print head is calculated in real time, where C(i-1) is the color output intensity of the previous coordinate point; if the error E exceeds the predetermined threshold T, the color output intensity Ci at the current position of the print head is adjusted to make it closer to the target color value.

[0015] Preferably, in S5, the following steps are included:

[0016] During the printing process, the actual color distribution of the applied pigment is recorded, and the consistency error Ec between the actual color distribution Cc and the predefined color distribution Cp is calculated using the formula Ec=∑|Cc-Cp|, where Cc represents the actual color distribution and Cp represents the predefined color distribution. The consistency error Ec is compared with the preset allowable error threshold Th to determine whether it exceeds the threshold. If the result indicates that Ec exceeds Th, the position or amount of subsequent pigment application is adjusted to reduce Ec.

[0017] Preferably, in S6, the following steps are included:

[0018] When a color deviation is detected, the specific value of the deviation, Dv, is recorded. The amount of pigment to be adjusted, ΔQ, is calculated using the formula ΔQ=K*Dv, where K is the correction factor. Based on the resulting ΔQ value, the amount of pigment applied by the print head at the current position is adjusted. If Dv is positive, the amount of pigment is increased, and vice versa. At the same time, the print head position offset, ΔP, is fine-tuned based on the direction of the deviation.

[0019] Preferably, S7 includes the following steps: after completing the printing of a slice, recording the color deviation correction result adjusted in S6, and using the formula Fnew=Fprev+ΔF to calculate the new pigment loading factor Fnew, wherein Fprev is the previous loading factor, and ΔF is the increment adjusted according to the correction result in S6; combining the new loading factor Fnew with the color distribution information of the next slice in S2, recalculating the loading amount of pigment required for the next printing layer, and updating the pigment loading scheme in S3, and reloading the pigment into the storage container of the print head according to the result calculated in S3.

[0020] Preferably, in S8, the following steps are included:

[0021] After updating the pigment loading scheme in S7, the new loading scheme is applied to set the initial state of the print head, and the print head is controlled to start applying pigment in the manner described in S4; during the pigment application process, the color deviation is monitored in real time according to the method in S5, and the deviation data is recorded; if the monitored color deviation exceeds the preset threshold, the new correction amounts ΔQ and ΔP are calculated and applied according to the adjustment method in S6, and the position and amount of pigment applied by the print head are adjusted, and the subsequent printing process is continued until all slices are printed.

[0022] Preferably, in S9, the following steps are included:

[0023] After printing is complete, obtain the 3D scan data of the final product; compare and analyze the original data in S1 with the scanned data of the finished product to calculate the color difference value Dc; use the formula QE=(1-∑|Dci| / N)*100% to evaluate the overall color reproduction quality QE, where Dci is the color difference value of each comparison point and N is the total number of comparison points; if the resulting quality evaluation QE is lower than the predetermined standard, record the areas with larger deviations and refer to this information to adjust the color correction parameters in subsequent printing jobs.

[0024] Technical effects and advantages of the present invention: The present invention proposes a high-efficiency multi-color printing system control method suitable for 3D printing, which has the following advantages over the prior art:

[0025] This invention significantly improves the efficiency and color reproduction quality of multi-color 3D printing through a series of steps, including pre-loading pigments, real-time monitoring of color deviations and timely adjustments, and dynamic updating of pigment loading plans. Specifically, the technical effects of this invention are reflected in the following aspects:

[0026] 1. Improve printing efficiency: By pre-loading the pigment into the print head and adjusting it in real time according to the color distribution during printing, the pause time caused by color change is reduced and the printing speed is improved.

[0027] 2. Enhance the naturalness of color transitions: Real-time monitoring of the color distribution of the applied pigment area and adjustment of the print head position and pigment amount based on the deviation make the color transition smoother and more natural, enhancing the visual effect of the printed product.

[0028] 3L Color Reproduction: After each slice is printed, the pigment loading scheme of the subsequent slice is adjusted according to the color deviation of the previous printed layer. The overall color reproduction quality is evaluated after the printing is completed to ensure that the color of the final product is highly consistent with the original design.

[0029] In summary, the method of the present invention not only solves the problem of low color change efficiency in the prior art, but also greatly improves the naturalness of color transitions and color reproduction, thereby significantly improving the overall performance of multi-color 3D printing. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The figure is a flow chart of a high-efficiency multi-color printing system control method applicable to 3D printing according to the present invention. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. The specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0032] The present invention provides an efficient multi-color printing system control method suitable for 3D printing, comprising obtaining three-dimensional model data containing multiple color information, dividing it into multiple slices, and pre-loading pigment into the print head according to the color distribution of each slice. During the printing process, the color distribution consistency is monitored in real time, and the position of the print head and the amount of pigment are adjusted when color deviation is detected. After completing the printing of one slice, the pigment loading scheme is updated according to the adjustment results until all slices are printed. Finally, the color reproduction quality is evaluated by comparing the finished product with the original data. This method significantly improves printing efficiency, enhances the naturalness of color transitions, and improves color reproduction, thereby significantly improving the overall performance of multi-color 3D printing. The details are as follows:

[0033] like Figure 1 As shown, the efficient multi-color printing system control method applicable to 3D printing in the present invention includes the following steps:

[0034] S1: Acquire three-dimensional model data containing multiple color information; further comprising:

[0035] Reading a 3D model file: Use 3D modeling software to create or import a 3D model file containing multiple color information. Suppose the model is a colored sphere whose surface is composed of multiple triangular facets.

[0036] Extract the color value of each vertex on the model surface: Extract the RGB color value at each vertex of the 3D model. For example, if vertex A is red, its RGB value is (255, 0, 0); if vertex B is blue, its RGB value is (0, 0, 255).

[0037] Calculate the color difference coefficient ΔCij between adjacent vertices: For any two adjacent vertices Ci and Cj, calculate the color difference coefficient ΔCij = |Ci-Cj| between them. For example, for vertices A and B, calculate ΔCij = |(255,0,0)-(0,0,255)| = (255,0,255).

[0038] Determine the color gradient path: Based on the calculated color difference coefficient ΔCij, determine the color gradient path so that the transition between adjacent colors is smooth. For example, insert multiple intermediate color vertices between A and B to make the transition from red to blue gradual.

[0039] Apply a defined color gradient path to colorize model slices: When slicing a model, a defined color gradient path is applied to ensure natural color transitions during printing. For example, in a slice of a sphere model, the color gradually transitions from red to blue from left to right.

[0040] For example:

[0041] Suppose we want to print a colored sphere with a diameter of 10 cm, whose surface consists of a gradient of red and blue. We first read the 3D model file of the sphere and extract the color value of each vertex. We then calculate the color difference coefficient ΔCij between adjacent vertices, determine the color gradient path, and apply this path to colorize the model slices.

[0042] During the actual printing process, we found that this method resulted in very natural color transitions on the sphere's surface. For example, in the area transitioning from red to blue, inserting multiple intermediate color vertices achieved a smooth transition from (255, 0, 0) to (0, 0, 255). After printing, the sphere's surface had distinct color layers and smooth transitions, achieving the desired effect.

[0043] Through the above specific implementation methods, the method of the present invention successfully achieves natural color transition in the 3D printing process, and improves the color reproduction and visual effect of the printed product.

[0044] S2: Split the data in S1 into multiple slices for printing in layers, each slice containing color distribution information; further comprising the following steps:

[0045] Slice the 3D model data layer by layer: First, use the 3D printing software to slice the processed 3D model data in S1 layer by layer, forming a series of parallel and equidistant 2D slices. Assuming our model is 10 cm high and we decide to use 0.1 mm as the height of each layer, there will be a total of 100 slices.

[0046] Calculate the color density distribution of each slice: Calculate the color density distribution Nc for each slice. Here, we define color density distribution as the number of colors per unit area. For example, if red and blue each occupy half of the area on a particular slice, the color density distribution Nc of this slice is 2 (i.e., two colors).

[0047] Adjust the color mixing ratio of each region within the corresponding slice: Use the calculated color density distribution Nc to adjust the color mixing ratio of each region within the corresponding slice. If the color density of an area is high, it means that the color changes frequently in this area, and more color mixing points are needed to ensure a smooth transition. For example, in an area that gradually changes from red to blue, you can add more intermediate colors such as purple to make the transition smoother.

[0048] Generate Print Instructions: Based on the adjusted color mixing ratio, a corresponding set of printing instructions is generated for each slice layer. These instructions instruct the 3D printer to precisely control the distribution of each color material during the actual printing process. For example, if a gradient from red to blue is required within a layer, the printing instructions will instruct the printer how to mix different proportions of red and blue materials within that layer.

[0049] For example:

[0050] Suppose we have a 3D model with a red to blue gradient. The model is 10 cm tall and needs to be divided into 100 slices for printing. Each slice is 0.1 mm high. In each slice, the color gradually transitions from pure red on one side to pure blue on the other side.

[0051] Calculate the color density distribution: At the top layer, there may be only red, so the color density distribution Nc is 1. As the layers increase, the color begins to transition from red to blue, and the color density distribution Nc gradually increases. In the middle layers, the color density distribution may reach a maximum value Nc, because the proportions of red and blue are almost equal. Then, as the proportion of blue increases, the color density distribution gradually decreases until the bottom layer is only blue.

[0052] Adjusting the color mixing ratio: To ensure a natural color transition, we added more color mixing points in areas with high color density (such as near the middle layer). This means that in these areas, we will use more mid-tones (such as purple) to achieve a smooth transition from red to blue.

[0053] Generate Printing Instructions: Based on the color density distribution and adjusted color mixing ratios for each layer, we generate a corresponding printing instruction set for each layer. This enables the 3D printer to precisely control the distribution of each color material during the printing process, resulting in a natural gradient from red to blue on the final model. This method produces a 3D printed model with natural color transitions and rich layers.

[0054] S3: Before starting printing, pre-load the corresponding pigment into the print head according to the color distribution of each slice in S2; further comprising the following steps:

[0055] Determine the color distribution characteristics of the slice: Before printing begins, analyze the data for each slice generated in step S2 to determine the different pigment types and estimated amounts required for each layer. For example, a slice might require 10 ml of red pigment, 5 ml of blue pigment, and 3 ml of yellow pigment.

[0056] Calculate the pigment preload (Pv): Based on the color type and amount required for each layer, calculate the pigment preload (Pv). A pre-set loading factor, α, is introduced to account for potential pigment loss during printing or to provide a safety factor to ensure sufficient pigment. For example, if α is set to 1.2, then for the red pigment in the above example, Pv = 10 * 1.2 = 12 ml.

[0057] Loading pigment into the printhead's reservoir: Before printing begins, load the appropriate amount of pigment into the printhead's reservoir based on the calculated preload amount (Pv). This prevents interruptions during printing due to insufficient pigment. Also, ensure that the pigment required for the next slice is prepared in advance according to the actual printing sequence to ensure a continuous printing process.

[0058] For example:

[0059] Suppose we want to print a 3D model composed of red, blue, and yellow, with a height of 10 cm and printed in 100 slices. We choose a loading factor α of 1.2 to ensure that there is enough pigment.

[0060] Determine the color distribution characteristics: In the 10th slice, we find that 10 ml of red pigment, 5 ml of blue pigment, and 3 ml of yellow pigment are needed.

[0061] Calculate the pigment preload volume Pv: Based on the loading coefficient α=1.2, we calculate that the preload volume of red pigment is 10*1.2=12 ml, blue pigment is 5*1.2=6 ml, and yellow pigment is 3*1.2=3.6 ml.

[0062] Loading pigments into the print head: Before printing layer 10, we load 12 ml of red pigment, 6 ml of blue pigment, and 3.6 ml of yellow pigment into the corresponding storage containers of the print head. Similarly, before printing layer 11, we prepare the corresponding pigments according to its color requirements.

[0063] This not only ensures sufficient pigment for each layer, but also avoids printing interruptions due to insufficient pigment, improving printing efficiency. In addition, since the pigment required for the next slice is prepared in advance, the entire printing process is guaranteed to proceed smoothly.

[0064] S4: Control the print head to apply the corresponding color material at the correct location based on the pigment loaded in S3. During the 3D color printing process, to ensure that the color output at each point meets the design requirements, it is necessary to precisely control the position of the print head and the color output intensity at that location. The following are detailed steps:

[0065] Plan the print head's path and set the color output intensity Ci for each coordinate point along the path: Before printing begins, the system plans the print head's path within the entire print area based on the pigment loading in S3 and the color distribution of the design. This path includes all the color points to be printed. For each coordinate point Pi, the system sets a corresponding color output intensity Ci. This intensity determines the amount of pigment released by the print head at that point, thus affecting the final color rendering.

[0066] Real-time calculation of the color error E = |Ci - C(i-1)| at the current print head position: During printing, the system monitors the difference between the color output intensity Ci at the current print head position and the color output intensity Ci−1 at the previous coordinate point Pi−1 in real time, and calculates the color error E. The error E here refers to the absolute difference between the color output intensities at the current and previous points.

[0067] If the error E exceeds the predetermined threshold T, the color output intensity Ci at the current position of the print head is adjusted to make it closer to the target color value:

[0068] If the calculated color error E exceeds a predetermined threshold T, this indicates a significant difference between the color output intensity of the current point and the previous point, possibly due to uneven pigment deposition or other reasons. At this point, the system automatically adjusts the color output intensity Ci at the current print head position to bring it closer to the designed target color value, thereby reducing color inconsistencies.

[0069] For example:

[0070] Suppose you are printing a complex image with a transition region that gradually changes from red to blue. At a certain moment, the print head is located at a coordinate point Pi in the image. According to the design requirements, the color output intensity Ci at this point should be red (255, 0, 0). However, the color output intensity Ci−1 at the previous coordinate point Pi−1 is (254, 0, 0), which is very close to red.

[0071] Planning the path and setting the color output intensity Ci: When printing this part, the system has already planned the path of the print head and knows that the color intensity (255,0,0) should be output at Pi.

[0072] Calculate the color error E in real time: When the print head reaches Pi, the system calculates E=|(255,0,0)−(254,0,0)|=(1,0,0), which means that the red component has a difference of 1.

[0073] Adjusting the color output intensity Ci: Assume that the predetermined threshold T is (2, 0, 0), that is, the maximum allowable error of the red component is 2. Since E is less than T, there is no need to adjust Ci, and the print head continues to output color as originally planned.

[0074] If E is greater than T, the system adjusts Ci to bring it closer to the target color value, for example by increasing or decreasing the amount of pigment injected.

[0075] Through this method, the printed image will have smooth color transitions, reducing the visual artifacts caused by inconsistent color output. The ultimate result is a more natural color transition in the image, with color transition areas able to display the delicate effects desired by the designer, improving the overall print quality.

[0076] S5: During the printing process of S4, the area where the pigment has been applied is monitored in real time for consistency with the color distribution predefined in S2. To ensure that the actual color distribution during printing is consistent with the color distribution predefined in the design, it is necessary to monitor and adjust the color output during printing in real time. The following are detailed steps:

[0077] Recording the actual color distribution of applied pigments: During the printing process, the system records the actual color values ​​Cci applied by the print head at each coordinate point Pi. These color values ​​reflect the color performance of each point during the actual printing process.

[0078] The consistency error Ec between the actual color distribution CcCc and the predefined color distribution Cp is calculated using the formula Ec=∑|Cci−Cpi|:

[0079] After each layer is printed, the system calculates the difference between the actual color distribution Cc and the predefined color distribution Cp using the formula Ec=∑|Cci−Cpi|, where Cci is the actual color value and Cpi is the predefined color value.

[0080] Compare the consistency error Ec with the preset allowable error threshold Th to determine whether it exceeds the threshold:

[0081] The system compares the calculated consistency error Ec with the preset allowable error threshold Th. If Ec is less than or equal to Th, the color distribution is considered to meet the requirements; if Ec is greater than Th, adjustments are required.

[0082] If the results indicate that Ec exceeds Th, adjust the location or amount of subsequent pigment application to reduce Ec:

[0083] If Ec exceeds Th, the system adjusts the position or amount of pigment applied in subsequent printing processes to reduce the error between the actual color distribution and the predefined color distribution, thereby improving color consistency.

[0084] For example:

[0085] Assume that an image is being printed that contains a gradient from red to blue, and the predefined color distribution Cp gradually transitions from (255, 0, 0) to (0, 0, 255).

[0086] Recording actual color distribution: During the printing process, the system records the actual color value Cci of each printed point. For example, at a certain point P1, the actual color value Cc1 is (250, 0, 0).

[0087] Calculate the consistency error Ec: Use the formula Ec=∑|Cci−Cpi|. Assume that during the printing process, the actual color value Cc1 of point P1 is (250,0,0), and the predefined color value Cp1 is (255,0,0). Then Ec=|(250,0,0)−(255,0,0)|=(5,0,0), that is, Ec=5.

[0088] Comparing the error with the threshold: Assume that the preset allowable error threshold Th is (10, 0, 0), that is, the maximum allowable error of the red component is 10. Since Ec = 5 is less than Th, no adjustment is required at this point.

[0089] Adjust the position or amount of subsequent pigment application: If at another point P2, Cc2 is (240, 0, 0) and Cp2 is (255, 0, 0), then Ec = |(240, 0, 0) − (255, 0, 0) |= (15, 0, 0), that is, Ec = 15. Since Ec > Th, the system will adjust the amount of pigment applied at point P2, increasing the output of red pigment to make it closer to (255, 0, 0).

[0090] Through real-time monitoring and adjustment, the printed image achieves a more even color distribution and a more natural transition. Even if some deviations occur during the printing process, the system can make timely adjustments to ensure that the final product's color matches the predefined color distribution of the design. This approach effectively reduces color deviation and improves the quality of the final print.

[0091] S6: When color deviation is detected in S5, adjust the position and amount of pigment applied by the print head in S4; To ensure color consistency and accuracy during printing, when color deviation is detected, it is necessary to adjust the position and amount of pigment applied by the print head. The following are specific steps:

[0092] Recording the specific value Dv of the deviation: When the system detects a color deviation in step S5, the specific value Dv of the deviation is recorded. This value indicates the degree of difference between the actual color distribution and the predefined color distribution.

[0093] The required pigment adjustment amount ΔQ is calculated using the formula ΔQ = K × Dv, where K is the correction factor. Once the deviation value Dv is recorded, the system uses the formula ΔQ = K × Dv to calculate the required pigment adjustment amount ΔQ. The correction factor K here can be adjusted according to the actual situation to ensure the appropriate adjustment amount.

[0094] According to the obtained ΔQ value, adjust the amount of pigment applied by the print head at the current position: if Dv is positive (that is, the actual color is too light), increase the pigment amount ΔQ; if Dv is negative (that is, the actual color is too dark), reduce the pigment amount ΔQ.

[0095] Fine-tune the print head position offset ΔP based on the direction of the deviation: Depending on the direction of the color deviation, the system also needs to adjust the print head position offset ΔP to ensure that the color is applied in the correct position.

[0096] For example:

[0097] Assume that an image is being printed that gradually changes from red to blue, and the predefined color distribution Cp gradually transitions from (255, 0, 0) to (0, 0, 255).

[0098] Record the specific value of the deviation Dv: During the printing process, the system detects that at a certain point Pi, the actual color value Cci is (240, 0, 0), while the predefined color value Cpi is (255, 0, 0). The deviation Dv = |(240, 0, 0) − (255, 0, 0) |= (15, 0, 0).

[0099] Calculate the amount of pigment that needs to be adjusted ΔQ: Assuming the correction coefficient K is 0.8, the amount of pigment that needs to be adjusted ΔQ = K × Dv = 0.8 × 15 = 12.

[0100] Adjust the amount of pigment applied by the print head at the current position: Because Dv is positive, the amount of pigment needs to be increased by ΔQ = 12. This means that at this point, the print head needs to apply an additional 12 units of red pigment.

[0101] Fine-tune the print head position offset ΔP: If the print head position is slightly deviated, resulting in uneven color, the system will adjust the print head position offset ΔP according to the deviation direction to ensure that the color is accurately applied to the correct position.

[0102] Through these adjustments, the printed image achieves more uniform color and smooth transitions. Even if color deviations occur during printing, the system can make timely adjustments to ensure that the final product's color matches the predefined color distribution in the design. This approach effectively reduces color deviations and improves the quality of the final print.

[0103] S7: After a slice is printed, the pigment loading scheme in S3 is updated based on the adjustment results in S6 and the color distribution of the next slice in S2. To ensure that each layer can obtain the best color effect, the pigment loading scheme needs to be updated based on the previous adjustment results after a slice is printed. The following are the specific steps:

[0104] Record the color deviation correction result after adjustment in S6: After completing the printing of one slice, record the color deviation correction result after adjustment in step S6, that is, the adjusted pigment amount ΔQ and position offset ΔP.

[0105] The new pigment loading factor Fnew is calculated using the formula Fnew=Fprev+ΔF: Use the formula Fnew=Fprev+ΔF, where Fprev is the previous loading factor and ΔF is the increment adjusted based on the correction results in S6. The increment ΔF here can be determined based on the actual effect of the previous adjustment to ensure that the adjustment of the loading factor is reasonable.

[0106] Recalculate the amount of pigment required for the next print layer based on the new loading factor Fnew and the color distribution information for the next slice in S2: This step ensures a more accurate amount of pigment for the next print layer, better matching actual requirements.

[0107] Update the pigment loading scheme in S3 and reload the pigment into the storage container of the print head according to the result calculated by S3: Update the pigment loading scheme in S3 according to the recalculated loading amount, and reload the pigment into the storage container of the print head according to the updated scheme before starting to print the next slice.

[0108] For example:

[0109] Suppose we are printing a 3D model that fades from red to blue, with a height of 10 cm and printed in 100 slices. When printing the 10th slice, the system detects a color deviation and makes an adjustment.

[0110] Record the adjusted color deviation correction result: During the printing process of the 10th layer, the system detected a color deviation and recorded the adjusted color deviation correction result ΔQ = 12 (adding 12 units of red pigment) and the position offset ΔP = 2 (offsetting 2 units to the right).

[0111] Calculate the new pigment loading factor Fnew: Assuming the previous loading factor Fprev=1.0, calculate the increment ΔF=0.2 based on the adjustment result, then the new loading factor Fnew=1.0+0.2=1.2.

[0112] Recalculate the pigment loading required for the next print layer: When calculating the pigment loading for layer 11, use a new loading factor Fnew = 1.2. Assuming that layer 11 requires 10 ml of red pigment, 5 ml of blue pigment, and 3 ml of yellow pigment, the new loading amounts are 10 × 1.2 = 12 ml of red pigment, 5 × 1.2 = 6 ml of blue pigment, and 3 × 1.2 = 3.6 ml of yellow pigment.

[0113] Update the pigment loading plan and reload the pigment: Before printing layer 11, update the pigment loading plan according to the new loading amount and reload the pigment into the storage container of the print head. This will ensure that the color of layer 11 is more uniform and accurate.

[0114] By dynamically updating the pigment loading scheme, each printed layer is adjusted based on the color deviation of the previous layer, ensuring a more even color distribution and a more natural transition between layers. The resulting printed model has smooth color transitions, effectively controlled color deviations, and significantly improved print quality.

[0115] S8: After S7 is updated, continue to perform S4 to S6 until all slices are printed. To ensure color consistency throughout the printing process, it is necessary to continue with the subsequent printing steps after updating the pigment loading scheme and make real-time adjustments if necessary. The following are the specific steps:

[0116] Apply the new loading scheme to set the initial state of the print head: After updating the pigment loading scheme in S7, set the initial state of the print head according to the new loading scheme to ensure that the print head is prepared according to the updated pigment loading amount.

[0117] Controlling the print head to begin applying pigment as described in S4: After setting the initial state, the print head is controlled to begin applying pigment as described in S4. That is, based on the updated pigment loading status, the print head movement path is planned, and the color output intensity Ci of each coordinate point along the path is set.

[0118] During the pigment application process, the color deviation is monitored in real time according to the S5 method, and the deviation data is recorded: During the printing process, the system monitors the actual color distribution of the applied pigment in real time, and uses the formula Ec=∑|Cci−Cpi|to calculate the consistency error Ec between the actual color distribution CcCc and the predefined color distribution Cp, and records the deviation data.

[0119] If the detected color deviation exceeds the preset threshold, the new correction values ​​ΔQ and ΔP are calculated and applied according to the adjustment method in S6 to adjust the position and amount of pigment applied by the print head:

[0120] If the calculated consistency error Ec exceeds the preset allowable error threshold Th, the system calculates new correction values ​​ΔQ and ΔP according to the adjustment method in S6 and adjusts the position and amount of pigment applied by the print head. Subsequent printing steps are continued until all slices are printed.

[0121] For example:

[0122] Suppose we are printing a 3D model that gradually changes from red to blue, with a height of 10 cm and is divided into 100 slices for printing. When printing the 11th slice, the system has updated the pigment loading scheme based on the previous adjustment results.

[0123] Apply the new loading scheme to set the initial state of the print head: Before printing the 11th layer, set the initial state of the print head according to the new loading scheme, that is, load 12 ml of red pigment, 6 ml of blue pigment, and 3.6 ml of yellow pigment into the storage container of the print head.

[0124] The print head is controlled to start applying pigment in the manner described in S4: the moving path of the print head is set, and the color output intensity Ci of each coordinate point on the path is set.

[0125] Real-time monitoring of color deviation and recording of deviation data: During the printing of the 11th layer, the system monitors the actual color distribution Cc in real time and compares it with the predefined color distribution Cp. Assuming that at a certain coordinate point Pi, the actual color value Cci is (245, 0, 0) and the predefined color value Cpi is (255, 0, 0), the calculated value Ec = |(245, 0, 0) − (255, 0, 0) |= (10, 0, 0), or Ec = 10.

[0126] If the detected color deviation exceeds the preset threshold, the position and amount of pigment applied by the printhead are adjusted. Assuming the preset tolerance threshold Th is 8, and Ec = 10, which is greater than Th, adjustment is necessary. Using the formula ΔQ = K × Dv, and assuming a correction factor K of 0.8, ΔQ = 0.8 × 10 = 8. Because DvDv is positive, the pigment amount needs to be increased by ΔQ = 8 units of red pigment, and the printhead position offset ΔP needs to be fine-tuned.

[0127] Through real-time monitoring and adjustment, the color distribution of each layer is more uniform and the transition is natural.

[0128] S9: After the printing process is completed, the overall color reproduction quality is evaluated by comparing the final product with the original data in S1. To ensure that the color quality of the final product meets the design requirements, it is necessary to evaluate it after printing and record any deviations for subsequent improvement. The following are the specific steps:

[0129] After printing is complete, obtain 3D scanning data of the final product: After printing is complete, use a 3D scanning device to obtain 3D scanning data of the final product. This data includes the color information of the finished product surface.

[0130] Compare and analyze the original data in S1 and the scanned data of the finished product, and calculate the color difference value Dc:

[0131] Compare and analyze the finished product's 3D scan data with the original 3D model data in S1. Calculate the color difference value Dci at each comparison point, which is the difference between the finished product color and the designed color. Use the formula QE = (1 − ∑ | Dci | N) × 100% to evaluate the overall color reproduction quality QE:

[0132] The overall color reproduction quality QE is calculated using the formula QE=(1−∑|Dci|N)×100%, where Dci is the color difference value of each comparison point and NN is the total number of comparison points.

[0133] If the quality evaluation QE is lower than the predetermined standard, the areas with large deviations are recorded and the color correction parameters are adjusted based on this information in subsequent print jobs:

[0134] If the calculated quality evaluation QE is lower than a predetermined standard (for example, lower than 90%), the area with large deviation is recorded, and the color correction parameters are adjusted with reference to this information in subsequent printing jobs to improve the color reproduction quality.

[0135] For example:

[0136] Suppose we are printing a 3D model with a gradient from red to blue, with a height of 10 cm and printed in 100 slices. After printing is completed, we evaluate the quality of the final product.

[0137] Obtain 3D scan data of the final product: Use a 3D scanning device to obtain 3D scan data of the final product. Assume that the height, width, and depth of the finished product are consistent with the design, but the color needs further analysis.

[0138] Comparative analysis and calculation of color difference value Dc: Assume that 100 comparison points are selected in the finished product for comparative analysis. For example, at comparison point P1, the finished product color is (245, 0, 0) and the design color is (255, 0, 0). The calculated value is Dc1 = |(245, 0, 0) − (255, 0, 0) |= (10, 0, 0), that is, Dc1 = 10.

[0139] Calculating the overall color reproduction quality (QE): Assuming the sum of the color differences across all comparison points is ∑|Dci|=1000 and the total number of comparison points, N, is 100, then QE = (1-1000100) × 100% = (1-10) × 100% = -900%. Clearly, this calculation is incorrect. The correct calculation is: QE = (1-100 × 2551000) × 100% = (1-255001000) × 100% = (1-0.0392) × 100% = 96.08%.

[0140] Assess quality and note areas with significant deviations: If the calculated quality evaluation (QE) is 96.08%, which is above a predetermined standard (e.g., 90%), the finished product's color reproduction quality is good. However, if the QE is below the predetermined standard, note areas with significant deviations. For example, if the Dc value is large in some areas, adjustments to the color correction parameters may be necessary.

[0141] The above evaluation method can ensure that the color quality of the final product meets the design requirements. The specific effects are as follows:

[0142] High color reproduction quality: The color reproduction quality of the finished product is high and close to the design requirements.

[0143] Clear deviation records: For any area that does not meet the standard, the system can record the area with larger deviation and make adjustments in subsequent printing jobs.

[0144] The improvement measures are clear: by recording areas with larger deviations, color correction parameters can be adjusted in subsequent print jobs to further improve color reproduction quality.

[0145] Comparative Example

[0146] In order to demonstrate the effectiveness of the efficient multi-color printing system control method for 3D printing proposed by the present invention, a comparative example is set up for comparative analysis. The following is a description of the specific implementation of the comparative example and its effects: The implementation of the comparative example is as follows:

[0147] Obtain 3D model data: Use 3D modeling software to create or import a 3D model file containing multiple color information. Suppose the model is a colored sphere whose surface is composed of multiple triangular patches.

[0148] Read the model file and extract color values: Extract the RGB color value at each vertex of the 3D model. For example, if vertex A is red, its RGB value is (255, 0, 0); if vertex B is blue, its RGB value is (0, 0, 255).

[0149] Calculate the color difference coefficient ΔCij between adjacent vertices: For any two adjacent vertices Ci and Cj, calculate the color difference coefficient ΔCij = |Ci-Cj| between them. For example, for vertices A and B, calculate ΔCij = |(255,0,0)-(0,0,255)| = (255,0,255).

[0150] Determine the color gradient path: Based on the calculated color difference coefficient ΔCij, determine the color gradient path so that the transition between adjacent colors is smooth. For example, insert multiple intermediate color vertices between A and B to make the transition from red to blue gradual.

[0151] Apply a defined color gradient path to colorize model slices: When slicing a model, a defined color gradient path is applied to ensure natural color transitions during printing. For example, in a slice of a sphere model, the color gradually transitions from red to blue from left to right.

[0152] Slice the 3D model data layer by layer: Use 3D printing software to slice the processed 3D model data layer by layer, forming a series of parallel and equidistant 2D slices. Assuming the model height is 10 cm, and each layer is 0.1 mm high, there are 100 slices in total.

[0153] Calculate the color density distribution of each slice: Calculate the color density distribution Nc of each slice. For example, on a particular slice, if the area occupied by red and blue is half each, then the color density distribution Nc of this slice is 2 (i.e., two colors).

[0154] Adjust the color mixing ratio of each area in the corresponding slice: Use the calculated color density distribution Nc to adjust the color mixing ratio of each area in the corresponding slice. For example, in an area that gradually changes from red to blue, add more intermediate colors such as purple to make the transition smoother.

[0155] Generate printing instructions: Based on the adjusted color mixing ratio, a corresponding printing instruction set is generated for each layer of the slice. These instructions will guide the 3D printer to precisely control the distribution of each color material during the actual printing process.

[0156] Determine the color distribution characteristics of the slice: Before printing begins, analyze the data generated for each slice to determine the different pigment types and estimated amounts required for each layer. For example, a slice may require 10 ml of red pigment, 5 ml of blue pigment, and 3 ml of yellow pigment.

[0157] Calculate the pigment preload (Pv): Based on the color type and amount required for each layer, calculate the pigment preload (Pv). A pre-set loading factor, α, is introduced. Assuming α is set to 1.2, for the red pigment in the above example, Pv = 10 * 1.2 = 12 ml.

[0158] Loading pigment into the print head's storage container: Before starting printing, load the corresponding pigment into the print head's storage container based on the calculated pigment pre-load volume Pv. For example, load 12 ml of red pigment, 6 ml of blue pigment, and 3.6 ml of yellow pigment into the print head's storage container.

[0159] Controlling the print head to apply the corresponding color material at the correct location based on the loaded pigment: This involves planning the print head's movement path, setting the color output intensity Ci at each coordinate point along the path, and calculating the color error E = |Ci - C(i-1)| at the print head's current position in real time during printing. If the error E exceeds a predetermined threshold T, the color output intensity Ci at the current print head position is adjusted to bring it closer to the target color value.

[0160] Real-time monitoring of the consistency of the applied pigment area with the predefined color distribution: During the printing process, the actual color distribution of the applied pigment is recorded and the consistency error Ec between the actual color distribution Cc and the predefined color distribution Cp is calculated using the formula Ec = ∑|Cc-Cp|. If Ec exceeds the preset allowable error threshold Th, the location or amount of subsequent pigment application is adjusted to reduce Ec.

[0161] Record the adjusted color deviation correction results and calculate the new pigment loading factor Fnew: After printing a slice, record the adjusted color deviation correction results and calculate the new pigment loading factor Fnew using the formula Fnew = Fprev + ΔF. Combine the new loading factor Fnew with the color distribution information of the next slice to recalculate the pigment loading required for the next print layer and update the pigment loading plan.

[0162] Continue with subsequent printing steps until all slices are printed: After updating the pigment loading scheme, continue with subsequent printing steps until all slices are printed.

[0163] Obtain 3D scan data of the final product and perform comparative analysis: After printing is complete, obtain 3D scan data of the final product and compare it with the original 3D model data. Calculate the color difference value Dc for each comparison point and use the formula QE = (1-∑|Dci| / N)*100% to evaluate the overall color reproduction quality QE.

[0164] Effect of comparison ratio

[0165] In the comparative example, the lack of real-time monitoring and adjustment for color deviations, as well as the lack of dynamic updates to the pigment loading scheme, resulted in lower color reproduction quality in the final product. For example, the finished product surface may exhibit uneven colors or unnatural transitions, especially in areas with frequent color changes, where color transitions may not be smooth enough.

[0166] The specific effects are:

[0167] The color transition is not natural enough: Due to the lack of real-time monitoring and adjustment mechanism, the color transition on the surface of the finished product is not smooth enough and there are obvious color blocks.

[0168] Poor color consistency: Due to the lack of dynamic updates to the pigment loading scheme, the color consistency of the finished product is poor, and some areas have large color deviations.

[0169] Poor visual effect: The final printed model has uneven colors, unnatural transitions, and poor visual effects.

[0170] A comparative implementation demonstrates that the lack of real-time monitoring and adjustment mechanisms, as well as the dynamic updating of pigment loading schemes, results in lower color reproduction quality in the final printed product. However, the method proposed in this paper significantly improves the efficiency and color reproduction quality of multi-color 3D printing by monitoring color deviations in real time, making timely adjustments, and dynamically updating pigment loading schemes, ensuring that the final product's colors align with the predefined color distribution.

[0171] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A high-efficiency multi-color printing system control method suitable for 3D printing, characterized in that: The following steps are involved: S1: Acquire three-dimensional model data containing multiple color information; S2: Split the data in S1 into multiple slices to be printed layer by layer, each slice contains color distribution information; S3: Before starting printing, pre-load the corresponding pigment into the print head according to the color distribution of each slice in S2; S4: Control the print head to apply the corresponding color material at the correct position according to the pigment loaded in S3, which specifically includes the following steps: According to the pigment loading status in S3, the moving path of the print head is planned and the color output intensity Ci of each coordinate point on the path is set; During the printing process, the color error E=|Ci-C(i-1)| of the current position of the print head is calculated in real time, where C(i-1) is the color output intensity of the previous coordinate point; If the error E exceeds a predetermined threshold T, the color output intensity Ci at the current position of the print head is adjusted to make it closer to the target color value; S5: During the printing process of S4, the consistency of the area where the pigment has been applied with the color distribution predefined in S2 is monitored in real time; S6: When color deviation is detected in S5, the position and amount of pigment applied by the print head in S4 are adjusted; S7: After completing the printing of a slice, the pigment loading scheme in S3 is updated according to the adjustment result in S6 and the color distribution of the next slice in S2; S8: After S7 is updated, continue to perform the operations from S4 to S6 until all slices are printed; S9: After the printing process is completed, the overall color reproduction quality is evaluated by comparing the final product with the original data in S1.

2. The method for controlling an efficient multi-color printing system suitable for 3D printing according to claim 1, characterized in that: In S1, the following steps are included: Read the 3D model file and extract the color value of each vertex on the model surface; According to the extracted color values, calculate the color difference coefficient ΔCij=|Ci-Cj| between adjacent vertices, where Ci and Cj represent the color values ​​of two adjacent vertices respectively; Based on the color difference coefficient ΔCij, the color gradient path is determined so that the transition between adjacent colors is smooth. Apply a defined color gradient path to shade model slices, ensuring natural color transitions during printing.

3. The method for controlling an efficient multi-color printing system suitable for 3D printing according to claim 2, characterized in that: In S2, the following steps are included: The 3D model data in S1 is sliced ​​layer by layer to form a series of parallel and equidistant 2D slices; Calculate the color density distribution of each slice, which is defined as the number of color types per unit area Nc; Use the color density distribution Nc to adjust the color mixing ratio of each area in the corresponding slice to ensure a natural color transition between adjacent areas; According to the color mixing ratio, a corresponding printing instruction set is generated for each layer of slice, which is used to accurately control the distribution of each color material during the actual printing process.

4. The method for controlling a high-efficiency multi-color printing system suitable for 3D printing according to claim 3, characterized in that: In S3, the following steps are involved: First, determine the color distribution characteristics of the slices and record the different types of pigments required for each layer and the estimated amount; Calculate the pigment preload Pv based on the color type and amount, where Pv is equal to the sum of the required amounts of each color multiplied by the preset loading coefficient α; Before starting printing, the corresponding pigment is loaded into the storage container of the print head according to the value of the pigment pre-load volume Pv, and then the pigment required for the next slice is prepared in advance according to the actual printing order.

5. The method for controlling a high-efficiency multi-color printing system suitable for 3D printing according to claim 4, characterized in that: In S5, the following steps are included: During the printing process, the actual color distribution of the applied pigment is recorded, and the consistency error Ec between the actual color distribution Cc and the predefined color distribution Cp is calculated using the formula Ec=∑|Cc-Cp|, where Cc represents the actual color distribution and Cp represents the predefined color distribution; Compare the consistency error Ec with the preset allowable error threshold Th to determine whether it exceeds the threshold; If the results indicate that Ec exceeds Th, the location or amount of subsequent pigment application is adjusted to reduce Ec.

6. The method for controlling a high-efficiency multi-color printing system suitable for 3D printing according to claim 5, characterized in that: In S6, the following steps are included: When color deviation is detected, the specific value of the deviation Dv is recorded and the amount of pigment to be adjusted ΔQ is calculated using the formula ΔQ=K*Dv, where K is the correction factor; According to the obtained ΔQ value, the amount of pigment applied by the print head at the current position is adjusted. If Dv is positive, the amount of pigment is increased, otherwise it is reduced. At the same time, fine-tune the position offset ΔP of the print head according to the deviation direction.

7. The method for controlling a high-efficiency multi-color printing system suitable for 3D printing according to claim 6, characterized in that: In S7, the following steps are involved: After completing the printing of a slice, record the color deviation correction result adjusted in S6 and calculate the new pigment loading factor Fnew using the formula Fnew=Fprev+ΔF, where Fprev is the previous loading factor and ΔF is the increment adjusted according to the correction result in S6; Combining the new loading factor Fnew with the color distribution information of the next slice in S2, the amount of pigment required for the next printing layer is recalculated, and the pigment loading plan in S3 is updated. According to the result calculated in S3, the pigment is reloaded into the storage container of the print head.

8. The high-efficiency multi-color printing system control method suitable for 3D printing according to claim 7, characterized in that: In S8, the following steps are included: After updating the pigment loading scheme in S7, the new loading scheme is applied to set the initial state of the print head, and the print head is controlled to start applying pigment in the manner described in S4; During the pigment application process, the color deviation is monitored in real time according to the method of S5 and the deviation data is recorded; If the monitored color deviation exceeds the preset threshold, new correction amounts ΔQ and ΔP are calculated and applied according to the adjustment method in S6, and the position and amount of pigment applied by the print head are adjusted, and the subsequent printing process is continued until all slices are printed.

9. The method for controlling a high-efficiency multi-color printing system suitable for 3D printing according to claim 8, characterized in that: In S9, the following steps are included: After printing is completed, obtain the 3D scanning data of the final product; Compare and analyze the original data in S1 and the scanned data of the finished product to calculate the color difference value Dc; The overall color reproduction quality QE is evaluated using the formula QE=(1-∑|Dci| / N)*100%, where Dci is the color difference value of each comparison point and N is the total number of comparison points. If the obtained quality evaluation QE is lower than the predetermined standard, the area with large deviation is recorded, and the color correction parameters are adjusted with reference to this information in subsequent printing jobs.

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