CN110722799B

CN110722799B - Large-format DLP type 3D printer dislocation shared seam eliminating method and system

Info

Publication number: CN110722799B
Application number: CN201911092112.3A
Authority: CN
Inventors: 韩月娟; 王宜怀; 张永; 潘建; 张蓉; 徐昕
Original assignee: Suzhou University
Current assignee: Suzhou University
Priority date: 2019-11-09
Filing date: 2019-11-09
Publication date: 2021-12-10
Anticipated expiration: 2039-11-09
Also published as: CN110722799A

Abstract

The invention discloses a method and a system for eliminating staggered and evenly-shared seams of a large-format DLP (digital light processing) type 3D printer, wherein the method comprises the following steps: uniformly slicing the three-dimensional model to generate a tangent plane bitmap; carrying out staggered segmentation on the tangent plane bitmap to generate a segmentation bitmap; and performing moving staggered splicing on the segmentation bitmap through a mobile projector to generate a three-dimensional model entity. The method can enlarge the forming size of the 3D printer with low additional cost, better solve the problem of seam, improve the overall quality of the model, reduce the complexity of hardware and have good expandability.

Description

Large-format DLP type 3D printer dislocation shared seam eliminating method and system

Technical Field

The invention relates to the technical field of 3D printing, in particular to a method and a system for eliminating staggered and evenly-shared seams of a large-format DLP (digital light processing) type 3D printer.

Background

In recent years, 3D printing technology has received a great deal of attention due to the declining price of equipment and the advent of related open source items. The 3D printing is an Additive Manufacturing (AM) technique, which builds an entity of a three-dimensional model by accumulating materials layer by layer in an accurate accumulation manner according to a layered Manufacturing principle. Compared with the traditional manufacturing mode, the technology simplifies the processes of die opening and die testing, shortens the product development period, reduces the material waste, and can quickly construct objects with very complex internal structures.

A DLP type 3D printer based on a Digital Light Processing (DLP) technology takes a DLP projector as exposure forming equipment and photosensitive resin as printing raw materials according to the technical principle of mask projection stereolithography, and printing layers cured layer by layer are stacked to generate a three-dimensional entity. DLP projecting apparatus has realized the high definition projection of three-dimensional model cross section pattern, with the ultraviolet light projection of section pattern to liquid photosensitive resin on, but the ultra-thin 3D of fast curing prints the layer. Compared with other 3D printing technologies, the technology has the outstanding characteristics of high printing precision and good surface smoothness of finished products, is widely applied to precision casting, biomedical treatment and the like, and becomes the focus of research in the current 3D printing industry.

The DLP type 3D printer is limited by the projection size of a projector, is mainly used for printing small-size parts at present, and is difficult to complete the forming work of a large model. The research status of the DLP type 3D printer in the field of large-format printing is mainly that a larger forming breadth is formed by a mode of single-projector moving splicing or multi-projector collaborative projection, but the research on the seam problem of the projection splicing part is less. In the aspect of large-breadth moving splicing, in 2002, Smith installs projection equipment on a mechanical system and controls the projection equipment to move on an X axis and a Y axis, so that the projection breadth is expanded. The Delta DLP 3D printer that Chenming Wu et al designed in 2016 uses three arms to drive the shaping platform and removes the concatenation, in the aspect of the seam processing, Lifang Wu et al proposed the even scheme of multi-projector energy in 2018, this scheme uses the projection mode that many projectors adopted handing-over department part to overlap, and adjust pixel grey level mask, thereby output the even ultraviolet light of energy, the seam problem that the illumination intensity inequality of seam department brought has been handled to a certain extent, but the machine based on this scheme design, the expansion of its shaping size relies on exposure equipment's increase, and is with high costs, the degree of difficulty of equipment maintenance has been increased.

When splicing projection is carried out, when the joint of the patterns projected for multiple times cannot be in pixel-level butt joint, seams are easy to form, and usually, when the movement distance is too large, a gap exists at the joint of the two projections of the generated model, and the model is easy to break; when the movement distance is too small, the light intensity of the joint of the two projections is greater than that of the rest part due to repeated exposure, so that a hard and prominent part is formed, and the surface quality of the model is influenced. Therefore, the research on the scheme of large-breadth moving splicing and seam elimination of the DLP type 3D printer is of great significance for improving the model quality.

Therefore, how to enlarge the molding size of the 3D printer with a smaller cost, solve the problem of seams at the projection splicing part, improve the overall quality of the model, and reduce the hardware complexity is a problem that needs to be solved urgently by those skilled in the art.

Disclosure of Invention

In view of the above problems, the present invention is to solve the problems that the cost for expanding the molding size of a 3D printer is high, and the joint projection is formed when the joint projection is performed, which affects the overall quality of the model.

The embodiment of the invention provides a method for eliminating staggered and evenly-shared seams of a large-format DLP (digital light processing) type 3D printer, which comprises the following steps:

uniformly slicing the three-dimensional model to generate a tangent plane bitmap;

carrying out staggered segmentation on the tangent plane bitmap to generate a segmentation bitmap;

and the mobile projector carries out mobile staggered splicing on the segmentation bitmap to generate a three-dimensional model entity.

In one embodiment, uniformly slicing the three-dimensional model to generate a tangent plane bitmap comprises:

and uniformly slicing the three-dimensional model by using a plane vertical to the Z axis according to the preset thickness to generate a tangent plane bitmap.

In one embodiment, the performing the staggered splitting on the tangent plane bitmap to generate a split bitmap includes:

segmenting the tangent plane bitmap to generate a segmentation pattern;

calculating effective pixels of the segmentation pattern according to preset offset pixels;

and filling the segmentation pattern according to the effective pixels of the segmentation pattern to generate a segmentation bitmap.

In one embodiment, the filling the segmentation pattern according to the effective pixels of the segmentation pattern to generate a segmentation bitmap includes:

filling the segmentation pattern to make the effective pixel of the segmentation pattern consistent with the pixel resolution width of a projector, wherein the following conditions are required to be met:

wherein, W_rRepresenting the width of the projector's projection resolution, L_iRepresenting the effective pixels in the X-axis direction of the leftmost segmentation pattern of the ith layer_iRepresenting the effective pixels, M, of the rightmost slice pattern in the X-axis direction_iRepresenting the cut pattern effective pixels divided by the middle of the leftmost and rightmost sides.

In one embodiment, the moving projector moves the rows to splice together with dislocation to generate a three-dimensional model entity, comprising:

a recording step: judging whether the segmentation bitmap is a full black picture or not, and recording a full black classification mark of the segmentation bitmap;

a judging step: judging whether the segmentation bitmap needs exposure or not according to the all-black classification mark of the segmentation bitmap; if the segmentation bitmap needs exposure, performing a calculation step;

a calculation step: obtaining effective pixels of a segmentation bitmap to be exposed, and calculating the distance to be moved to the next exposure position according to the effective pixels;

an exposure step: moving the projector to the next exposure position according to the distance to be moved, and performing a calculation step until the exposure of a layer of section is completed;

a generation step: and performing a calculation step and an exposure step on the section of the next layer, positioning the exposure position of each segmented picture, and superposing and printing the layers to generate a three-dimensional model entity.

In a second aspect, the present invention further provides a large-format DLP type 3D printer misalignment and seam sharing elimination system, including:

the slicing module is used for uniformly slicing the three-dimensional model to generate a tangent plane bitmap;

the staggered segmentation module is used for carrying out staggered segmentation on the tangent plane bitmap to generate a segmentation bitmap;

and the generating module is used for performing mobile staggered splicing on the segmentation bitmap by a mobile projector to generate a three-dimensional model entity.

In one embodiment, the slicing module includes:

In one embodiment, the mis-alignment singulation module comprises:

the segmentation sub-module is used for segmenting the tangent plane bitmap to generate a segmentation pattern;

the effective pixel calculation sub-module is used for calculating effective pixels of the segmentation pattern according to preset offset pixels;

and the filling sub-module is used for filling the segmentation patterns according to the effective pixels of the segmentation patterns to generate segmentation bitmaps.

In one embodiment, the fill submodule includes:

In one embodiment, the generating module includes:

the recording submodule is used for judging whether the segmentation bitmap is a full black picture or not and recording a full black classification mark of the segmentation bitmap;

the judgment submodule is used for judging whether the segmentation bitmap needs to be exposed or not according to the all-black classification mark of the segmentation bitmap; if the segmentation bitmap needs exposure, performing a calculation step;

the distance to be moved calculation submodule is used for acquiring effective pixels of the segmentation bitmap to be exposed and calculating the distance to be moved to the next exposure position according to the effective pixels;

the exposure submodule is used for moving the projector to the next exposure position according to the distance to be moved, and performing calculation until the exposure of a layer of section is completed;

and the generation submodule is used for performing a calculation step and an exposure step on the section of the next layer, positioning the exposure position of each segmented picture, and superposing and printing the layers to generate a three-dimensional model entity.

The technical scheme provided by the embodiment of the invention has the beneficial effects that at least:

the method for eliminating the staggered and evenly-shared seam of the large-format DLP type 3D printer, provided by the embodiment of the invention, aims at the problem that the 3D printer is small in forming size based on a DLP technology, adopts a movable splicing method, enlarges the projection range by moving the DLP projector, breaks through the limitation of the DLP projector on the forming size of the 3D printer, and enlarges the forming size of the 3D printer with low additional cost. Aiming at the problem that joints can appear when a model is printed by adopting a mobile splicing method due to screen distortion and installation errors, an SS-SEM algorithm is provided based on the principle of dislocation sharing, the joint errors can not be accumulated at one position by a dislocation method, the surface of the printed model is more natural, the joints are eliminated, the aim of improving the quality of the model is achieved, meanwhile, the hardware complexity is reduced, and the expandability is good.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

fig. 1 is a flowchart of a method for eliminating a staggered and evenly-shared seam of a large-format DLP type 3D printer according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a method for eliminating a staggered and evenly-shared seam of a large-format DLP type 3D printer according to an embodiment of the present invention;

fig. 3 is a flowchart of step S102 according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a slicing and re-slicing process provided by an embodiment of the present invention;

FIG. 5 is a schematic view of a seam location provided by an embodiment of the present invention;

FIG. 6 is a schematic diagram illustrating a comparison of printing products by different splicing methods according to example 1 of the present invention;

FIG. 7 is a schematic diagram of the wolf head model provided in example 2;

FIG. 8 is a schematic illustration of a turbine model provided in example 2;

FIG. 9 is a schematic illustration of a text relief model provided in example 2;

FIG. 10 is a diagram of a printed product of printing a small wolf head using schemes 1-4 of example 2;

FIG. 11 is a diagram of a printed product from a turbine of example 2 printed using schemes 1-4;

FIG. 12 is a diagram of a printed product of example 2 in which text embossments were printed using schemes 1-4;

FIG. 13 is a time consuming comparison line graph of example 2 using a different moving splicing scheme;

fig. 14 is a block diagram of a large-format DLP type 3D printer misalignment sharing seam elimination system according to an embodiment of the present invention;

fig. 15 is a mechanical schematic diagram of a 3D printer based on DLP principle according to an embodiment of the present invention.

Detailed Description

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

Referring to fig. 1-2, a method for eliminating a staggered and evenly-shared seam of a large-format DLP type 3D printer according to an embodiment of the present invention includes: s101 to S103;

s101, uniformly slicing the three-dimensional model to generate a tangent plane bitmap.

Uniformly slicing the three-dimensional model by using a plane vertical to a Z axis according to a preset thickness to generate a tangent plane bitmap; setting the preset thickness to be 0.025 mm-0.05 mm, and gradually cutting the model upwards from the bottom of the model to obtain a series of cross sections of the model, so as to generate a section bitmap of the N layers of slices.

S102, carrying out staggered segmentation on the tangent plane bitmap to generate a segmentation bitmap.

S103, moving, staggering and splicing the segmentation bitmaps through a mobile projector to generate a three-dimensional model entity.

In this embodiment, based on the idea of dislocation evenly-sharing (error evenly-sharing), the joint area of each layer is staggered through the SS-SEM algorithm, so that the errors at the joints are evenly-shared at different positions of each layer, the joint errors are not accumulated at one position, the surface of the printed model is more natural, the joints are eliminated, the goal of improving the quality of the model is achieved, meanwhile, the complexity of hardware is reduced, and the expandability is good. And the three-dimensional model entity is spliced and printed by moving the dislocation, so that the forming size of the 3D printer can be enlarged by lower additional cost.

In one embodiment, referring to fig. 3, in step S102, performing staggered slicing on the tangent bitmap to generate a sliced bitmap, including:

s1021, calculating effective pixels of the segmentation pattern according to preset offset pixels;

s1022, segmenting the tangent plane bitmap to generate a segmentation pattern;

and S1023, filling the segmentation pattern according to the effective pixels of the segmentation pattern to generate a segmentation bitmap.

For example, as shown in fig. 4, the three-dimensional model is divided into three blocks, a represents a slicing step, b represents a slicing step, and c represents a slicing pattern filling step, the pixel width of each slicing pattern is calculated according to the number of offset pixels, the pixel width of each slicing pattern is defined as an effective pixel, and then the effective pixel is expanded to a larger size, and the number of slicing blocks is increased.

Wherein the dislocation of seams of each layer is realized by changing the width of the leftmost cutting pattern and the rightmost cutting pattern of each layer. Filling the segmentation pattern to make the effective pixel of the segmentation pattern consistent with the pixel resolution width of a projector, wherein the following conditions are required to be met:

Specifically, the calculation process of the effective pixel is as follows:

in order to ensure that the generated picture is consistent with the resolution of a projector and the picture is not stretched and deformed during full-screen projection, the split pattern needs to be placed on the left side of the picture, and the insufficient part on the right side is filled with a black background, because the widths of the leftmost side pattern and the rightmost side pattern change along with different layer numbers, the moving and staggered splicing in the step S103 is influenced, so O (Offset Pixels, units: Pixels) is introduced as the joint position Offset parameter of the adjacent layer, and a variable E (Effective Pixels) is introduced to record the pixel width occupied by the split pattern in the split bitmap.

Let the projector resolution width (X-axis direction) be W_rThe model is divided into N layers, after the ith (

i

1, 2, 3.., N) section bitmap is cut, M cut bitmaps are formed, and the jth (

j

1, 2, 3.., M) cut bitmap is providedEffective pixel E_(i，j)The calculation method of (2) is as follows:

according to O and W_rA threshold value T may be calculated, which will be used to determine E_(i，j)And assist in calculating E_(i，j)The value of (c).

And after T is obtained, calculating the value of E of the segmentation bitmap at each position respectively.

Calculating the leftmost segmentation effective pixel of the ith layer according to a threshold value obtained by the formula (2); removing the segmentation on the leftmost side and the rightmost side, wherein effective pixels of the middle section are all projector resolution pixel widths; according to the formula (1), the sum of the effective pixels sliced at the leftmost side and the rightmost side of the ith layer is W_rTherefore, the rightmost sliced effective pixel number can use W_r-E_(i，1)Calculation of E_(i，j)The calculation result of (2) is shown in formula (3):

in this embodiment, as shown in fig. 5, d represents a seam position, and by using a staggered splitting algorithm, the arrangement of seams will be in a V shape, so that sudden change of offset positions will not occur during the sharing process, and seam errors will not be accumulated at one place, thereby better solving the seam problem and improving the overall quality of the model.

In one embodiment, the moving projector performs moving staggered stitching on the segmentation bitmap to generate a three-dimensional model entity, including:

a judging step: judging whether the segmentation bitmap needs exposure or not according to the all-black classification mark of the segmentation bitmap; if the segmentation bitmap needs exposure, performing a calculation step; if the all-black classification mark of the segmentation bitmap is all-black, the three-dimensional model entity is directly generated without exposure;

an exposure step: moving the projector to the next exposure position according to the distance to be moved, and performing a calculation step until the exposure of a layer of section is completed; wherein, the DLP projector is controlled to move to the next exposure position along the X axis;

a generation step: calculating and exposing the section of the next layer, positioning the exposure position of each segmented picture, and superposing and printing the layers to generate a three-dimensional model entity; and controlling the forming table top to lift one layer along the Z axis, and performing a calculation step and an exposure step on a next layer of section.

In the embodiment, the errors at the joints can be uniformly distributed on different positions of each layer by adopting movable staggered splicing, the joint errors cannot be accumulated at one position, the surface of the printed model is more natural, and the joints are eliminated.

Specifically, as shown in fig. 6, the effect of performing moving staggered stitching on the segmentation bitmap is as follows:

example 1:

for example, in the DLP projector used in this embodiment, the resolution parameter is 1280 × 800, and the projection range is 63.36mm × 39.63 mm.

And respectively printing a cuboid small block with the size of 30mm 15mm 2.5mm by adopting four modes of non-splicing (e), moving and splicing twice by two times without processing a seam (f), setting overlapped pixels, editing an overlapped area into gray (g) and adopting an SS-SEM algorithm (h) scheme.

The formed product is a relatively complete smooth surface piece without splicing, but the size of the product cannot be expanded, and the finished product can be used as a reference object for seam treatment effect.

By adopting the method of moving and splicing layer by layer for two times without processing the seam (f), the seam error of 0.1mm is always accumulated at one position, a relatively obvious seam is presented, and the middle spliced part is very fragile and can be broken into two pieces along the spliced position when being taken down from the forming table board.

Neither gap is generated by the method of setting overlapping pixels and editing the overlapping area to gray (g) nor the SS-SEM algorithm (h). However, on the surface of the model, the method of setting the overlapping pixels and editing the overlapping area to be gray (g) is slightly different from other positions in the curing hardness of the gray overlapping area, and the docking deviation of the pixels is also reflected in the area.

Errors at the seams of the model printed by the SS-SEM algorithm (h) are uniformly distributed to different pixel positions of each layer, and a layer of slice (with the thickness of 0.05mm) formed at the end of the model shows an unobvious trace due to no coverage of the upper slice, and can be ignored.

The experimental effect of the misalignment sharing seam elimination method of the large-format DLP type 3D printer is described below by a complete example.

Example 2:

for example, for a model printed without using a splicing method, the length and width of the original model are both smaller than those of the projection surface of the projector, so that the model can be printed, the length, width and height of the original model are both enlarged by 2 times and exceed the forming range of one-time projection of the projector, and the model can be printed only by using movable splicing. As shown in FIGS. 7-9, the length 26.37mm, width 20.49mm and height 9.50mm (denoted as V) are selected for this embodiment₁) The small wolf head has a length of 25.00mm, a width of 25.00mm and a height of 10.44mm (marked as V)₂) And a turbine wheel of length 38.0mm, width 14.8mm, height 1.5mm (denoted as V)₃) The text relief STL model of (1) is used as a test sample, and the printing result is consistent with the conclusion at the effect evaluation.

As shown in fig. 10-12, the methods of printing without stitching, stitching without removing the seam, processing the seam by overlapping pixels, and processing the seam by staggered stitching using SS-SEM algorithm are respectively denoted as schemes 1-4 (denoted as 1, 2, 3, and 4 in fig. 10-12), and the specific parameters of the model and the printing time consumption are as follows:

as can be seen from the above table, the small size of the small model results in a small number of layers for cutting, and the printing time is shortest. The number of layers of the model printed by the splicing method is enlarged to 2 times of the original number, the forming moving distance of each layer is increased, and the forming time is prolonged. In the model printed without seam elimination, as shown in fig. 10, the middle of the wolf head, especially the nose, has obvious seams, as shown in fig. 11, the middle of the turbine has a gap penetrating the whole cylinder up and down, as shown in fig. 12, and in the partial enlarged view of the character relief, the middle of the character relief has obvious seams and the bottom has partial pixels which are not well butted, and meanwhile, the seam area is relatively weak, and the model is easy to break along the seams. And the quality of the model printed by adopting the gray overlapping pixels and the SS-SEM algorithm scheme is improved. However, the grayscale overlap scheme is where the overlap is different from other areas, where errors accumulate, the overlap area slightly protrudes from other areas and the pattern pixel butting deviations also appear concentrated there. The SS-SEM algorithm only shows fine joint marks at the joint formed by the uppermost segmentation bitmap by using a moving staggered splicing scheme, and the surface quality is better.

The time consumption of the printing model adopting the three modes of mobile splicing is shown in fig. 13, the SS-SEM algorithm is adopted for processing the joints in a staggered splicing mode (scheme 4), each layer is compared with a common mobile splicing method which does not adopt an evenly-shared joint eliminating method, each layer is possibly divided into more blocks according to parameter setting, and each formed layer is provided with one more exposure period. However, as the number of times of splicing of one layer increases, the ratio of the time duration of the increase gradually decreases. The scheme of overlapping pixels to process seams (scheme 3) has the printing and forming time equivalent to that of a staggered splicing method, but the pixels of the overlapped area of each cut picture and other cuts need to be edited in the slicing stage to change the pixels from white to gray, so the slicing processing time is longer.

In this embodiment, to the problem that 3D printer shaping size is less based on DLP technique, adopt the method of removing the concatenation, enlarge the projection range through removing the DLP projecting apparatus, break through the restriction of DLP projecting apparatus to 3D printer shaping size. Aiming at the problem that seams can appear when a mobile splicing method is adopted to print a model due to screen distortion and installation errors, an SS-SEM algorithm is provided based on the principle of dislocation sharing: uniformly slicing a model by using a plane vertical to a Z axis to obtain tangent plane bitmaps of N layers of slices, carrying out staggered segmentation on each tangent plane bitmap according to offset pixel parameters by a staggered re-segmentation method to obtain segmentation patterns with different widths, carrying out black pixel filling on the right sides of the segmentation patterns to obtain the segmentation bitmaps of the size of the primary projection size of the DLP projector, so that each layer of slices forms M segmentation bitmaps with staggered splicing positions and adjacent layers, and the ordered set of the segmentation bitmaps forms a data source for staggered splicing printing; and secondly, positioning the exposure position of each segmented picture according to the offset pixels by adopting a moving staggered splicing forming method, controlling the projector to move along the X axis, realizing staggered forming of the segmented bitmaps, and generating an entity of the three-dimensional model by overlapping the printing layers. The dislocation method ensures that the joint errors cannot be accumulated at one position, the surface of the printed model is more natural, the joint is eliminated, and the aim of improving the quality of the model is fulfilled. In addition, the embodiment has good expandability, when a model with a larger format needs to be printed, only the number of times of movement of the DLP projector needs to be increased, namely, the movement range of the DLP projector and the size of a molding table top are expanded in mechanical design, and a slicing preprocessing program on software provides a parameter configuration interface and sets parameters such as a larger number of slicing blocks.

Based on the same inventive concept, the embodiment of the invention also provides a large-format DLP type 3D printer dislocation shared seam elimination system, and as the principle of the problem solved by the device is similar to the method for eliminating the large-format DLP type 3D printer dislocation shared seam, the implementation of the device can refer to the implementation of the method, and repeated parts are not described again.

The large-format DLP type 3D printer staggered and evenly-shared seam eliminating system provided by the embodiment of the invention is shown in fig. 14 and comprises:

the slicing module 141 is configured to uniformly slice the three-dimensional model to generate a tangent plane bitmap;

the staggered segmentation module 142 is configured to perform staggered segmentation on the tangent plane bitmap to generate a segmentation bitmap;

and the generating module 143 is configured to perform mobile staggered stitching on the segmentation bitmap by using a mobile projector, so as to generate a three-dimensional model entity. Specifically, the projector is controlled to move and splice on the X axis, and the splicing function in the Y axis direction can be conveniently expanded by adding mechanical parts such as a guide rail.

In one embodiment, the slicing module 141 includes:

and uniformly slicing the three-dimensional model by using a plane vertical to the Z axis according to the preset thickness to generate a tangent plane bitmap. Setting the preset thickness to be 0.025 mm-0.05 mm, and gradually cutting the model upwards from the bottom of the model to obtain a series of cross sections of the model, so as to generate a section bitmap of the N layers of slices.

In one embodiment, the misalignment splitting module 142 includes:

the segmentation submodule 1421 is configured to segment the tangent bitmap to generate a segmentation pattern;

an effective pixel calculation sub-module 1422, configured to calculate effective pixels of the segmentation pattern according to preset offset pixels;

and the filling sub-module 1423 is configured to fill the segmentation pattern according to the effective pixels of the segmentation pattern, so as to generate a segmentation bitmap.

In one embodiment, the fill submodule 1423 includes:

wherein, W_rRepresenting the width of the projector's projection resolution, L_iRepresenting the leftmost slice of the ith layerEffective pixel of pattern X-axis direction, R_iRepresenting the effective pixels, M, of the rightmost slice pattern in the X-axis direction_iRepresenting the cut pattern effective pixels divided by the middle of the leftmost and rightmost sides.

In one embodiment, the generating module 143 includes:

a recording sub-module 1431, configured to determine whether the bitmap is an all-black picture, and record an all-black classification flag of the bitmap;

the judgment sub-module 1432 is configured to judge whether the segmentation bitmap needs to be exposed according to the all-black classification flag of the segmentation bitmap; if the segmentation bitmap needs exposure, performing a calculation step; if the all-black classification mark of the segmentation bitmap is all-black, the three-dimensional model entity is directly generated without exposure;

the to-be-moved distance calculation sub-module 1433 is configured to obtain an effective pixel of the to-be-exposed segmentation bitmap, and calculate a to-be-moved distance to a next exposure position according to the effective pixel;

the exposure sub-module 1434 is configured to move the projector to a next exposure position according to the distance to be moved, and perform the calculation step until the exposure of the section of the layer is completed; wherein, the DLP projector is controlled to move to the next exposure position along the X axis;

the generation submodule 1435 is configured to perform a calculation step and an exposure step on a next slice, locate an exposure position of each sliced picture, and generate a three-dimensional model entity by superimposing the printed layers.

As shown in fig. 15, the system is based on a 3D printer based on the DLP principle, and is characterized in that a DLP projector 1 is fixedly arranged on an X-axis screw rod 2, so that the DLP projector 1 can horizontally move left and right along the X-axis, and a molding table 3 is fixedly arranged on a Z-axis screw rod 4, so that the molding table 3 can vertically move up and down along the Z-axis, a DLP light engine 5 is arranged below the X-axis screw rod 2, and the DLP light engine 5 horizontally moves along the X-axis, so that the projection range of the DLP projector 1 is enlarged, and further the limitation of the DLP projector 1 on the molding size of the 3D printer is broken. When the model of more big breadth is printed to needs, only need increase the number of times that DLP projecting apparatus 1 removed, through mechanical parts extension DLP projecting apparatus 1 migration range and the 3 sizes of shaping mesa such as increase guide rail on the 3D printer promptly, and then the ascending concatenation function in extension Y axle direction for this system has good scalability.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. Large format DLP type 3D printer dislocation is joint elimination method equally shared, its characterized in that includes:

the mobile projector carries out mobile staggered splicing on the segmentation bitmap to generate a three-dimensional model entity;

the dislocation segmentation is carried out to the tangent plane bitmap, and a segmentation bitmap is generated, and the method comprises the following steps:

segmenting the tangent plane bitmap to generate a segmentation pattern;

calculating effective pixels of the segmentation pattern according to preset offset pixels; carrying out staggered segmentation on each section bitmap according to offset pixel parameters by a staggered re-segmentation method to obtain segmentation patterns with different widths, and carrying out black pixel filling on the right sides of the segmentation patterns;

filling the segmentation pattern according to the effective pixels of the segmentation pattern to generate a segmentation bitmap;

the mobile projector carries out mobile staggered splicing on the segmentation bitmap to generate a three-dimensional model entity, and the method comprises the following steps:

2. The method of eliminating the dislocated shared seam of the large-format DLP type 3D printer in claim 1, wherein the uniformly slicing the three-dimensional model to generate the tangent plane bitmap comprises:

3. The method for eliminating the misplaced shared seams of the large-format DLP type 3D printer according to claim 1, wherein the step of filling the segmentation patterns according to the effective pixels of the segmentation patterns to generate the segmentation bitmaps comprises:

4. Big breadth DLP type 3D printer dislocation is joint seam elimination system of equalling share, its characterized in that includes:

the generating module is used for performing mobile staggered splicing on the segmentation bitmap by a mobile projector to generate a three-dimensional model entity;

the dislocation segmentation module includes:

the effective pixel calculation sub-module is used for calculating effective pixels of the segmentation pattern according to preset offset pixels; carrying out staggered segmentation on each section bitmap according to offset pixel parameters by a staggered re-segmentation method to obtain segmentation patterns with different widths, and carrying out black pixel filling on the right sides of the segmentation patterns;

the filling sub-module is used for filling the segmentation patterns according to the effective pixels of the segmentation patterns to generate segmentation bitmaps;

the generation module comprises:

5. The large format DLP type 3D printer misalignment and seam elimination system of claim 4, wherein the dicing module comprises:

6. The large format DLP type 3D printer misalignment and seam elimination system of claim 4, wherein the fill submodule comprises: