CN113895036B - Continuous self-adaptive path planning method for additive manufacturing - Google Patents
Continuous self-adaptive path planning method for additive manufacturing Download PDFInfo
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- CN113895036B CN113895036B CN202111244086.9A CN202111244086A CN113895036B CN 113895036 B CN113895036 B CN 113895036B CN 202111244086 A CN202111244086 A CN 202111244086A CN 113895036 B CN113895036 B CN 113895036B
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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
- B29C64/30—Auxiliary operations or equipment
- B29C64/386—Data acquisition or data processing for additive manufacturing
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- 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
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Abstract
The invention relates to a continuous self-adaptive path planning method for additive manufacturing, which is used for partitioning a polygon and forming a continuous filling path, thereby reducing breakpoints, improving the filling efficiency and improving the product quality, and can realize the purpose of self-adaptive widening and filling of a region by adjusting the number of filling line segments of a filling region, changing the actual filling width, and then controlling the corresponding filling width and adjusting the wire feeding speed.
Description
Technical Field
The invention relates to the technical field of additive manufacturing, in particular to a continuous adaptive path planning method for additive manufacturing.
Background
In the additive manufacturing technology, scan filling path planning is performed on slice outlines of a three-dimensional model after layered slicing, which is one of the key technologies.
At present, a scanning filling path is generated by adopting a reciprocating linear method or an offset contour method for a polygonal section contour, for example, the polygonal contour in fig. 1 has a plurality of end points in the scanning filling process, so that the scanning efficiency is low, and when a three-dimensional product is generated, the appearance of the product is poor due to a plurality of break points.
Disclosure of Invention
Aiming at the defects in the prior art, one of the purposes of the invention is to provide a continuous adaptive path planning method for additive manufacturing, which reduces the idle stroke and the breakpoint of the filling inside a polygon, avoids the frequent opening and closing of a printing nozzle and improves the printing efficiency.
The above object of the present invention is achieved by the following technical solutions:
a method of continuous adaptive path planning for additive manufacturing, comprising the steps of:
s1, acquiring a slice contour line;
s2, acquiring a filling area:
s2.1: traversing and covering the whole slice contour line by adopting one or more parallel scanning lines, forming a plurality of intersection points between the scanning lines and the slice contour line, and if two points adjacent to the intersection points on the slice contour line are positioned on the same side of the scanning lines or coincide with the scanning lines, setting the intersection points as partition points I;
s2.2: forming a plurality of intersection points between the scanning straight line passing through the first partition point and the slice contour line, and if the intersection points are adjacent to the first partition point, setting the intersection points as second partition points;
s2.3: the first subarea points on the same scanning line are connected to form subarea line segments;
s2.4: the adjacent partition line segments and the slice contour line are surrounded to form a plurality of closed filling areas;
s3, path planning:
s3.1: the same partition point I or partition point II and partition line segments exist between the filling areas, and the filling areas are adjacent filling areas;
s3.2: generating one or more filling paths, wherein each filling path is composed of sequentially adjacent filling areas, and the sequence of the filling paths is the sequence of printing a plurality of non-repeated filling areas;
s4, filling:
s4.1: each filling area is preset with a plurality of filling line segments parallel to the scanning straight line;
s4.2: setting a filling starting point and a filling end point of each filling area according to the moving direction of the filling path, wherein the filling starting point and the filling end point are both positioned at the end points of the filling line segments, the filling starting point and the filling end point of the first filling area of each path are randomly selected, and the filling starting point of the adjacent last filling area and the filling starting point of the next filling area in the same filling path are the same point;
s4.3: and printing and connecting a filling starting point, a filling line segment and a filling end point in the same filling path in sequence along the direction of the filling path, and traversing and printing filling areas on all the filling paths.
The present invention in a preferred example may be further configured to:
wherein step S3.2 comprises:
s3.2-1: adding numbering marks for all filling areas;
s3.2-2: if the two filling areas are adjacent filling areas, connecting the number marks corresponding to the two filling areas to form an area adjacency network;
s3.2-3: and traversing all filling paths in the obtained area adjacency network, and selecting the combination of the minimum number of filling paths.
The present invention in a preferred example may be further configured to:
wherein step S2 further includes:
s2.5: changing the relative angle a between the scanning line and the slice contour line;
s2.6: step S2.1 to step S2.5 are traversed, a combination mode of a plurality of middle filling areas is obtained, wherein 0 degree < a <180 degrees;
s2.7: and selecting the combination with the least filling area.
The present invention in a preferred example may be further configured to:
step S4.1 includes:
s4.1-1: acquiring a filling width H of the filling area vertical to the scanning line;
s4.1-2: the number n of filled line segments in the filled region is obtained,for printing maximum width, omegaminTo print a minimum width;
step S4.2 further includes:
s4.2-1: regarding the area covered by printing along the filling line segments as a rectangle, regarding the area covered by printing each filling area as a quadrangle, and setting the end points of each quadrangle to A, B, C, D in turn in the counterclockwise direction;
s4.2-2: if only one common intersection point exists between two adjacent filling areas, selecting the intersection point as the printing end point of the last filling area;
if a common scanning line segment exists between two adjacent filling areas, selecting a partition point II which is intersected between the scanning line segment and the slicing wheel expansion line as a printing end point of the last filling area.
The present invention in a preferred example may be further configured to:
the printing path in step S4.3 includes several modes in sequence:
first, printing along the end point of a filling line segment to the end point of another filling line segment;
secondly, printing along the filling line segment;
thirdly, printing two filling line segments along a sine wave path;
and the direction of the print path is parallel to the fill line segment or perpendicular to the fill line segment.
The present invention in a preferred example may be further configured to: and if the third printing path is adopted in the filling area, selecting the adjacent filling line segment with the minimum length difference in the filling area and filling by adopting the third printing path.
The present invention in a preferred example may be further configured to: the step S1 further includes biasing the inner and outer boundaries of the slice contour inward by a distance of the fill width, respectively.
In summary, the present invention includes at least one of the following beneficial effects:
1. the continuous filling path is formed by partitioning the polygon, so that the breakpoints are reduced, the filling efficiency is improved, and the product quality is improved;
2. the purpose of self-adaptive widening filling of the area can be achieved by adjusting the number of filling line segments in the filling area, changing the actual filling width, controlling the corresponding filling width and adjusting the wire feeding speed;
3. the distance of the internal offset filling width forms an offset line, and when the actual filling is carried out, the part close to the section contour line is printed along the offset line, so that the idle stroke of the internal filling of the polygon is reduced, the printing spray head is prevented from being frequently opened and closed, and the printing efficiency is improved;
4. the slice contour lines are divided into different filling area combinations through scanning lines at different angles, and the combination of the least filling area is selected, so that the subsequent filling path can be conveniently planned and selected.
Drawings
FIG. 1 is a slice outline in the first embodiment;
FIG. 2 is a schematic view of the fit of a scan line to a slice profile line;
FIG. 3 is a schematic diagram of filling a partition;
FIG. 4 is a schematic diagram of the planning of a fill path;
FIG. 5 is a schematic illustration of a print path plan for even fill segments;
FIG. 6 is a schematic diagram of a print path plan for odd fill segments;
FIG. 7 is a schematic representation after polygon filling.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
The first embodiment is as follows:
a continuous adaptive path planning method for additive manufacturing is provided, which is to show the results of each step by taking a revolving body as an example for understanding,
s1, acquiring a slice outline as shown in an attached figure 1.
S2. building a fill zone in conjunction with the slice profile in fig. 1, as shown in fig. 2 and 3:
s2.1: traversing and covering the whole slice contour line by adopting one or more parallel scanning lines, forming a plurality of intersection points between the scanning lines and the slice contour line, and if two points adjacent to the intersection points on the slice contour line are positioned on the same side of the scanning lines or coincide with the scanning lines, setting the intersection points as partition points I;
s2.2: forming a plurality of intersection points between the scanning straight line passing through the first partition point and the slice contour line, and if the intersection points are adjacent to the first partition point, setting the intersection points as second partition points;
s2.3: the first subarea points on the same scanning line are connected to form subarea line segments;
s2.4: the adjacent partition line segments and the slice contour line are surrounded to form a plurality of closed filling areas;
the areas filled in the section contour line are regularly divided through the steps, so that the subsequent preparation for orderly filling is facilitated.
And referring to fig. 4, s3. path planning:
s3.1: the same partition point I or partition point II and partition line segments exist between the filling areas, and the filling areas are adjacent filling areas;
s3.2: generating one or more filling paths, wherein the filling paths are the sequence of printing a plurality of non-repeated filling areas, each filling path is composed of sequentially adjacent filling areas, and the method specifically comprises the following steps:
s3.2-1: adding numbering marks for all filling areas;
s3.2-2: if the two filling areas are adjacent filling areas, connecting the number marks corresponding to the two fillings, traversing and judging the relation of all the filling areas, and forming an area adjacency relation network;
s3.2-3: all the filling paths in the area adjacency network are obtained in a traversing mode, and the combination of the minimum number of filling paths is selected, wherein the selected filling paths are 1-2-3-4-8-6-5-7-9-10-14-12-11-13, so that filling breakpoints are effectively reduced.
Finally, as shown in fig. 5 to 7, s4. fill:
s4.1: a plurality of filling line segments parallel to the scanning straight line are preset in each filling area, and the response parameters, the filling width omega and the wire feeding speed v are prequalifiedwA traveling speed vtFilling width h, wire diameter dw,And comprises the following specific steps:
s4.1-1: acquiring a filling width H of the filling area vertical to the scanning line as H;
s4.1-2: the number n of filled line segments in the filled region is obtained,for printing maximum width, omegaminFor printing the minimum width, the actual filling widthTherefore, the purpose of self-adaptive widening filling of the area can be achieved by adjusting the number of the filling line segments of the filling area, changing the actual filling width, and then controlling the corresponding filling width and adjusting the wire feeding speed.
S4.2: the method comprises the following steps of setting a filling starting point and a filling end point of each filling area according to the moving direction of filling paths, wherein the filling starting point and the filling end point are both positioned at the end points of filling line segments, the filling starting point and the filling end point of the first filling area of each path are randomly selected, the filling starting point of the adjacent last filling area and the filling starting point of the next filling area in the same filling path are the same point, and the method comprises the following specific steps:
s4.2-1: regarding the area covered by printing along the filling line segments as a rectangle, regarding the area covered by printing each filling area as a quadrangle, and setting the end points of each quadrangle to A, B, C, D in turn in the counterclockwise direction;
s4.2-2: if only one common intersection point exists between two adjacent filling areas, selecting the intersection point as the printing end point of the last filling area;
if a common scanning line segment exists between two adjacent filling areas, selecting a partition point II which is intersected between the scanning line segment and the slicing wheel expansion line as a printing end point of the last filling area.
S4.3: sequentially printing and connecting a filling starting point, a filling line segment and a filling end point in the same filling path along the filling path direction, and traversing and printing filling areas on all the filling paths;
the printing path in step S4.3 includes several modes in sequence:
first, printing along the end point of a filling line segment to the end point of another filling line segment;
secondly, printing along the filling line segment;
thirdly, printing two filling line segments along a sine wave path;
and the direction of the print path is parallel to the fill line segment or perpendicular to the fill line segment.
And in the actual filling process, if a third printing path is adopted in the filling area, selecting the adjacent filling line segment with the minimum length difference in the filling area and filling by adopting the third printing path.
Meanwhile, before actual filling, the inner and outer boundaries of the slice contour line are respectively biased inwards by the distance of the filling width to form a bias line, and during actual filling, the part close to the slice contour line is printed along the bias line, so that the idle stroke of filling in the polygon is reduced, the printing spray head is prevented from being frequently opened and closed, and the printing efficiency is improved; and the feeding speed and the wire feeding speed are adjusted by filling the space, so that the accumulation condition in the polygonal boundary area is reduced, and the printing quality is improved.
Example two:
the difference from the first embodiment is that:
wherein step S3.2 further comprises:
s2.5: changing the relative angle a between the scanning line and the slice contour line;
s2.6: step S2.1 to step S2.5 are traversed, a combination mode of a plurality of middle filling areas is obtained, wherein 0 degree < a <180 degrees;
s2.7: and selecting the combination with the least filling area.
The slice contour lines are divided into different filling area combinations through scanning lines at different angles, and the combination of the least filling area is selected, so that the subsequent filling path can be conveniently planned and selected.
The embodiments of the present invention are preferred embodiments of the present invention, and the scope of the present invention is not limited by these embodiments, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.
Claims (7)
1. A method of continuous adaptive path planning for additive manufacturing, characterized by: the method comprises the following steps:
s1, acquiring a slice contour line;
s2, constructing a filling area:
s2.1: traversing and covering the whole slice contour line by adopting one or more parallel scanning lines, forming a plurality of intersection points between the scanning lines and the slice contour line, and if two points adjacent to the intersection points on the slice contour line are positioned on the same side of the scanning lines or coincide with the scanning lines, setting the intersection points as partition points I;
s2.2: forming a plurality of intersection points between the scanning straight line passing through the first partition point and the slice contour line, and if the intersection points are adjacent to the first partition point, setting the intersection points as second partition points;
s2.3: the first subarea points on the same scanning line are connected to form subarea line segments;
s2.4: the adjacent partition line segments and the slice contour line are surrounded to form a plurality of closed filling areas;
s3, path planning:
s3.1: the same partition point I or partition point II and partition line segments exist between the filling areas, and the filling areas are adjacent filling areas;
s3.2: generating one or more filling paths, wherein each filling path is composed of sequentially adjacent filling areas, and the sequence of the filling paths is the sequence of printing a plurality of non-repeated filling areas;
s4, filling:
s4.1: each filling area is preset with a plurality of filling line segments parallel to the scanning straight line;
s4.2: setting a filling starting point and a filling end point of each filling area according to the moving direction of the filling path, wherein the filling starting point and the filling end point are both positioned at the end points of the filling line segments, the filling starting point and the filling end point of the first filling area of each path are randomly selected, and the filling starting point of the adjacent last filling area and the filling starting point of the next filling area in the same filling path are the same point;
s4.3: and printing and connecting a filling starting point, a filling line segment and a filling end point in the same filling path in sequence along the direction of the filling path, and traversing and printing filling areas on all the filling paths.
2. A method of continuous adaptive path planning for additive manufacturing according to claim 1, wherein: wherein step S3.2 comprises:
s3.2-1: adding numbering marks for all filling areas;
s3.2-2: if the two filling areas are adjacent filling areas, connecting the number marks corresponding to the two filling areas to form an area adjacency network;
s3.2-3: and traversing all filling paths in the obtained area adjacency network, and selecting the combination of the minimum number of filling paths.
3. A method of continuous adaptive path planning for additive manufacturing according to claim 2, wherein: wherein step S2 further includes:
s2.5: changing the relative angle a between the scanning line and the slice contour line;
s2.6: step S2.1 to step S2.5 are traversed, a combination mode of a plurality of middle filling areas is obtained, wherein 0 degree < a <180 degrees;
s2.7: and selecting the combination with the least filling area.
4. A method of continuous adaptive path planning for additive manufacturing according to claim 1, wherein: step S4.1 includes:
s4.1-1: acquiring a filling width H of the filling area vertical to the scanning line;
s4.1-2: the number n of filled line segments in the filled region is obtained,ωmaxfor printing maximum width, omegaminTo print a minimum width;
step S4.2 further includes:
s4.2-1: regarding the area covered by printing along the filling line segments as a rectangle, regarding the area covered by printing each filling area as a quadrangle, and setting the end points of each quadrangle to A, B, C, D in turn in the counterclockwise direction;
s4.2-2: if only one common intersection point exists between two adjacent filling areas, selecting the intersection point as the printing end point of the last filling area;
if a common scanning line segment exists between two adjacent filling areas, selecting a partition point II which is intersected between the scanning line segment and the slicing wheel expansion line as a printing end point of the last filling area.
5. A method of continuous adaptive path planning for additive manufacturing according to claim 4, wherein: the printing path in step S4.3 includes the following modes:
first, printing along the end point of a filling line segment to the end point of another filling line segment;
secondly, printing along the filling line segment;
thirdly, printing two filling line segments along a sine wave path;
and the direction of the print path is parallel or perpendicular to the fill line segments.
6. A method of continuous adaptive path planning for additive manufacturing according to claim 5, wherein: and if the third printing path is adopted in the filling area, selecting the adjacent filling line segment with the minimum length difference in the filling area and filling by adopting the third printing path.
7. A method of continuous adaptive path planning for additive manufacturing according to claim 1, wherein: before the filling in step S4, the inner and outer boundaries of the slice outline are respectively offset inward by the distance of the filling width.
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CN115503240A (en) * | 2022-09-14 | 2022-12-23 | 南京衍构科技有限公司 | Additive manufacturing path planning generation method |
CN115489113A (en) * | 2022-09-27 | 2022-12-20 | 湖南华曙高科技股份有限公司 | Laser scanning method and device for manufacturing three-dimensional object and storage medium |
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