CN109648841A - A kind of multi-direction multiple degrees of freedom 3D printing dicing method - Google Patents
A kind of multi-direction multiple degrees of freedom 3D printing dicing method Download PDFInfo
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- CN109648841A CN109648841A CN201811504274.9A CN201811504274A CN109648841A CN 109648841 A CN109648841 A CN 109648841A CN 201811504274 A CN201811504274 A CN 201811504274A CN 109648841 A CN109648841 A CN 109648841A
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- Prior art keywords
- printing
- freedom
- multiple degrees
- dicing method
- point
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
- B29C64/10—Processes of additive manufacturing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
- B29C64/20—Apparatus for additive manufacturing; Details thereof or accessories therefor
- B29C64/227—Driving means
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
- B29C64/20—Apparatus for additive manufacturing; Details thereof or accessories therefor
- B29C64/245—Platforms or substrates
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
- B29C64/30—Auxiliary operations or equipment
- B29C64/386—Data acquisition or data processing for additive manufacturing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B33—ADDITIVE MANUFACTURING TECHNOLOGY
- B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- B33Y10/00—Processes of additive manufacturing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B33—ADDITIVE MANUFACTURING TECHNOLOGY
- B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- B33Y30/00—Apparatus for additive manufacturing; Details thereof or accessories therefor
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B33—ADDITIVE MANUFACTURING TECHNOLOGY
- B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- B33Y50/00—Data acquisition or data processing for additive manufacturing
Abstract
The invention discloses a kind of multi-direction multiple degrees of freedom 3D printing dicing methods, belong to 3D printing system technical field, including multiple groups slave arm, every group of slave arm includes two parallel bars, slave arm drives moving platform to move horizontally by ball screw, moving platform center is fixedly installed with printing head, ball screw is perpendicular to ground configuration, cradle turntable is equipped with below moving platform, its top is equipped with production workpiece substrate, cradle turntable is able to drive Z-direction and Y-direction rotation of the production workpiece substrate in three-dimensional coordinate, equipment meets five axis 3D printing demands, compared with traditional three axis printing device manufacture crafts, reduce working strength, fabrication direction changeability makes Temperature Distribution be unlikely to excessively to concentrate, reduce production model deformation factor, improve hand over efficiency and product quality.
Description
[technical field]
The invention belongs to 3D printing system technical field, especially a kind of multi-direction multiple degrees of freedom 3D printing dicing method.
[background technique]
3D printing technique is also known as rapid shaping technique, different from conventional casting techniques, and 3D printing technique is soft by computer
Part handles production workpiece, by adding support to production workpiece, to production workpiece layering, generates path planning, molding system
System achievees the purpose that make workpiece according to the planning in path.It, being capable of rapid shaping for especially complex workpiece.However, due to
Manufacture craft is more complicated, occurs many external factor interference, such as temperature field in manufacturing process, and stress field etc. influences.For big
Dimension workpiece make when, due to work pieces process direction determine, processing from begin it is constant to finishing direction, cause in this way temperature by
Hot uneven, stress is concentrated.In manufacturing process, when stress cannot discharge in time, once discharging, production workpiece will appear to be split stress
The defects of trace, cavity, alice.These defects directly affect the quality of production workpiece.It is specific insufficient as follows:
Alias is obvious, and precision is low.When fabrication direction and fabrication orientation have forming angle, shape is generated between the layers
The scraggly trace of shape such as ladder, i.e. alias.At present during 3D printing, fabrication direction and slice direction are being made
Before it has been determined that from start to finish direction is constant.
More based on large scale model defect, efficiency is slow.Large scale model, on the one hand, due to extraneous factors such as temperature, stress
It influences, it is cracked in workpiece manufacturing process, the defects of warpage etc..On the other hand, for being needed before suspension beam structure processing and fabricating
To add support to model, these supports are also required to processing and fabricating, virtually increase working strength, reduce processing efficiency.
[summary of the invention]
It is an object of the invention to overcome the above-mentioned prior art, a kind of multi-direction multiple degrees of freedom 3D printing is provided and is cut
Piece method reduces alias, guarantees to shorten Production Time while production workpiece accuracy, promotes producing efficiency and workpiece matter
Amount eliminates warpage defect.
In order to achieve the above objectives, the present invention is achieved by the following scheme:
A kind of multi-direction multiple degrees of freedom 3D printing dicing method, comprising the following steps:
Step 1, STL tringle coal is loaded, series of points and tri patch is obtained, establishes point sequence respectively, is stored
Corresponding tri patch relationship；
Step 2, according to point sequence reference-calibrating point, it is used for geodetic line computation, constructs Morse function using geodesic distance,
And to the function normalization；
Step 3, normalized data are used for extreme point and saddle point calculates, obtain Initial R eeb figure, Reeb figure has at this time
Redundant data obtains Reeb skeleton drawing by being filtered amendment optimization；
Step 4, customized planar layer direction, printing head (4) prolongs path planning direction production workpiece after layering.
A further improvement of the present invention lies in that:
Step 2 reference-calibrating point is chosen according to Euclidean space apart from one of farthest two points in SLT model:
Wherein, Vi,VjIndicate that model tri patch apex coordinate, i, j indicate vertex number, max indicates Vi,VjMaximum value,
I=1 ..., N, j=1 ..., N, N expression are counted in total.
Geodetic line computation in step 2 is by all vertex in dijkstra's algorithm searching tri patch to datum mark
Geodesic curve.
Printing head (4) is first made along Z-direction by planning path layer by layer in step 4.
Compared with prior art, the invention has the following advantages:
The present invention passes through the connection of slave arm and ball screw, so that slave arm is able to drive moving platform and moves horizontally, and
Ball screw is arranged vertically so that printing head is in the state of vertical silent flatform pedestal always, while cradle turntable is able to drive
Production workpiece substrate is rotated in Z-direction and Y-direction, and equipment is made to meet five axis 3D printing demands, with traditional three axis printing devices
Manufacture craft is compared, and working strength is reduced, and fabrication direction changeability makes Temperature Distribution be unlikely to excessively to concentrate, reduces production
Model deformation factor improves hand over efficiency and product quality.
[Detailed description of the invention]
Fig. 1 is the structural schematic diagram of apparatus of the present invention；
Process flow chart Fig. 2 of the invention；
Fig. 3 is the Reeb skeleton drawing after optimization；
Fig. 4 is the straight skeleton plane slice map based on Reeb figure after model area segmentation；
Fig. 5 is traditional three axis print system production process charts；
Wherein: 1- silent flatform pedestal；2- makes workpiece substrate；3- slave arm；4- printing head；5- moving platform；6- cradle
Turntable；7- ball screw.
[specific embodiment]
In order to enable those skilled in the art to better understand the solution of the present invention, below in conjunction in the embodiment of the present invention
Attached drawing, technical scheme in the embodiment of the invention is clearly and completely described, it is clear that described embodiment is only
The embodiment of a part of the invention, instead of all the embodiments.Based on the embodiments of the present invention, ordinary skill people
The model that the present invention protects all should belong in member's every other embodiment obtained without making creative work
It encloses.
It should be noted that term " includes " and " having " and their any deformation, it is intended that covering is non-exclusive
Include, for example, the process, method, system, product or equipment for containing a series of steps or units are not necessarily limited to clearly arrange
Those of out step or unit, but may include be not clearly listed or it is solid for these process, methods, product or equipment
The other step or units having.
The invention will be described in further detail with reference to the accompanying drawing:
With reference to Fig. 1, the multi-direction multiple degrees of freedom 3D printing slicing device of the present invention, printing head 4 is fixed on moving platform 5
Center, three groups of slave arms 3 (every group of two parallel bars) drive moving platforms 5 to move horizontally, and slave arm 3 passes through ball wire
Bar 7 moves；Three groups of ball screws 7 are mounted on silent flatform pedestal 1, ensure that printing head is in vertical silent flatform pedestal always
1；Cradle turntable 6 is mounted on silent flatform pedestal 1, and production workpiece substrate 2 is installed on cradle turntable 6, and cradle turntable 6 drives production
Workpiece substrate 2 is in Z-direction rotation and Y-direction rotation, to cause the device to meet the needs of five axis 3D printings.
Such as Fig. 2, the multi-direction multiple degrees of freedom 3D printing dicing method of the present invention, first load STL tringle coal are obtained
A series of point and tri patch establish point sequence and the corresponding tri patch relationship of storage respectively.It is demarcated according to point sequence
Datum mark is used for geodetic line computation, constructs Morse function using geodesic distance, right then in order to guarantee model robustness
Morse function normalization.Normalized data are used for the calculating of extreme point and saddle point.And then Initial R eeb figure is obtained, at this time
Reeb figure has redundant data, by being filtered amendment optimization, according to the Reeb skeleton drawing after optimization, customized planar layer side
To.After layering, spray head is made along path planning direction.
Such as Fig. 3, for the present embodiment by taking part model 8 as an example, part model 8 is overarm square structure front view, file format
It is " .STL "." .STL " model stores point, normal vector and tri patch information.In a model according to Euclidean space distance
One of farthest two points choose datum mark:
Wherein, Vi,VjIndicate that model tri patch apex coordinate, i, j indicate vertex number, max indicates Vi,VjMaximum value,
I=1 ..., N, j=1 ..., N, N expression are counted in total.
After selecting datum mark, pass through the geodetic on all vertex in dijkstra's algorithm searching tri patch to the datum mark
Line, and then calculate geodesic distance.Morse function is fluid attribute itself and Reeb figure bridge, and Morse theory can guarantee to extract
The robustness of skeleton.Morse function is constructed by geodesic distance, height function or Laplce's equation.Later, right
Morse function normalization.Normalized data are used for the calculating of extreme point and saddle point.And then Initial R eeb figure is obtained, at this time
Reeb figure has redundant data, by being filtered amendment optimization.Three middle polyline 9 of figure is exactly the Reeb skeleton drawing after optimization, according to
Part model 8 is carried out model area segmentation by Reeb skeleton drawing, carries out plane to model area using Reeb skeleton change direction
Slice, figure four can see part model 8 by region segmentation into two regions, increase material printing device by five axis and made,
Manufacturing process has priority.Print head 4 is made along Z-direction according to planning path layer by layer first, one of region
After completing, cradle turntable 6 is rotated by 90 ° around Y direction, is carried out in addition according to fabrication orientation before according to planning path
The production in one region, until completing.
Fig. 5 is traditional three axis printing device production process charts, to carry out plus support 10 before making first to part model 8,
This model is carried out later to carry out planar layer along Z-direction containing support section, path planning is obtained later, along path
Direction production is planned, until completing.It can be seen that traditional three axis printing devices increase new workload in the production process, need
Process support 10 is wanted, support is more, and efficiency is also low, while fabrication direction from the beginning to end cannot be changed at random along Z-direction
Become, lead to that temperature distribution is non-uniform in process in this way, stress is excessively concentrated, and will appear warpage, crackle when stress release
The defects of, the workpiece ultimately generated is unqualified.
Compared with traditional three axis printing device manufacture crafts, five axis printing devices reduce five axis printing device manufacture crafts
Working strength, fabrication direction changeability make Temperature Distribution be unlikely to excessively to concentrate, and reduce production model deformation factor, improve
Processing efficiency and product quality.
The above content is merely illustrative of the invention's technical idea, and this does not limit the scope of protection of the present invention, all to press
According to technical idea proposed by the present invention, any changes made on the basis of the technical scheme each falls within claims of the present invention
Protection scope within.
Claims (4)
1. a kind of multi-direction multiple degrees of freedom 3D printing dicing method, which comprises the following steps:
Step 1, STL tringle coal is loaded, series of points and tri patch are obtained, establishes point sequence respectively, storage is corresponding
Tri patch relationship；
Step 2, according to point sequence reference-calibrating point, it is used for geodetic line computation, constructs Morse function using geodesic distance, and right
The function normalization；
Step 3, normalized data are used for extreme point and saddle point calculates, obtain Initial R eeb figure, Reeb figure has redundancy at this time
Data obtain Reeb skeleton drawing by being filtered amendment optimization；
Step 4, customized planar layer direction, printing head (4) prolongs path planning direction production workpiece after layering.
2. multi-direction multiple degrees of freedom 3D printing dicing method as described in claim 1, which is characterized in that step 2 reference-calibrating
Point is chosen according to Euclidean space apart from one of farthest two points in SLT model:
Wherein, Vi,VjIndicate that model tri patch apex coordinate, i, j indicate vertex number, max indicates Vi,VjMaximum value, i=
1 ..., N, j=1 ..., N, N expression are counted in total.
3. multi-direction multiple degrees of freedom 3D printing dicing method as described in claim 1, which is characterized in that geodesic curve in step 2
It calculates, is by all vertex in dijkstra's algorithm searching tri patch to the geodesic curve of datum mark.
4. multi-direction multiple degrees of freedom 3D printing dicing method as described in claim 1, which is characterized in that print spray in step 4
Head (4) is first made along Z-direction by planning path layer by layer.
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| CN201811504274.9A CN109648841A (en) | 2018-12-10 | 2018-12-10 | A kind of multi-direction multiple degrees of freedom 3D printing dicing method |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110537962A (en) * | 2019-08-08 | 2019-12-06 | 天津工业大学 | rapid 3D printing puncture operation guide plate method |
| CN112659544A (en) * | 2020-12-02 | 2021-04-16 | 西安交通大学 | Thin-wall tubular model slicing method and system of five-axis 3D printer and printing method |
| CN113021873A (en) * | 2021-03-23 | 2021-06-25 | 深圳市创想三维科技有限公司 | Three-dimensional printing method and device, computer equipment and storage medium |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112659544A (en) * | 2020-12-02 | 2021-04-16 | 西安交通大学 | Thin-wall tubular model slicing method and system of five-axis 3D printer and printing method |
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Application publication date: 20190419 |