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CN-122020956-A - Angle-controlled annular-strip profile partition turning scanning linear path planning method and system

CN122020956ACN 122020956 ACN122020956 ACN 122020956ACN-122020956-A

Abstract

The invention relates to the technical field of additive manufacturing, and discloses an angle-controlled annular-strip profile partition turning scanning linear path planning method and system, wherein the method comprises the steps of obtaining profile data; if the contour data is annular, splitting and converting the contour data into two strip-shaped contours, dividing each strip-shaped contour into a plurality of sub-contours according to an angle threshold value, inwards biasing each sub-contour according to biasing parameters, generating intersecting lines of scanning lines and contour line segments for each biased sub-contour, sequentially constructing filling paths, outputting partition path data of the whole strip-shaped contour, and combining the partition path data of the two strip-shaped contours to obtain partition turning scanning filling paths of the complete annular contour. The method aims at optimizing a thermal circulation mode by carrying out partition turning scanning filling on the annular or strip-shaped slice profile, improving internal stress distribution and improving the forming quality of parts.

Inventors

  • XING FEI
  • FEI SHIGANG
  • LI MINGJIE
  • SHI JIANJUN

Assignees

  • 南京中科煜宸激光技术有限公司

Dates

Publication Date
20260512
Application Date
20251218

Claims (10)

  1. 1. An angle-controlled annular-strip profile partition direction-changing scanning straight line path planning method is characterized by comprising the following steps: Acquiring contour data of a planar annular shape or a strip shape of a slice of the additive manufactured part; If the contour data is an annular contour, splitting the annular contour into two strip-shaped contours; Dividing each bar profile into a plurality of sub-profiles according to an angle threshold, wherein each of the sub-profiles after cutting has an initial scanning direction and a scanning line arrangement direction; Inwards biasing each sub-profile according to the bias parameters; For each biased sub-contour, generating intersection lines of scanning lines and contour line segments according to corresponding initial scanning directions, scanning line arrangement directions and filling interval parameters, sequentially constructing filling paths, and outputting zonal path data of the whole bar-shaped contour; and merging the partition path data of the two bar-shaped outlines to obtain a partition turning scanning filling path of the complete annular outline.
  2. 2. The angle-controlled ring-bar profile zoned direction-changing scanning straight line path planning method according to claim 1, wherein the ring profile is split and converted into two bar profiles, comprising the following steps: Inputting annular inner and outer contour data, constructing a straight Line, and solving intersection points A, B of the straight Line and the inner and outer contours through dot product relation between adjacent points of the outer contours and normal vectors of the Line; Calculating an inner contour center point, combining the intersection point A, B with dirA, dir and_ SPLITRECDELTA parameters to construct a segmentation rectangle, and determining vertex coordinates of the segmentation rectangle according to the positive and negative properties of vAB.dot (dirA), wherein four vertices P0, P1, P2 and P3 of the generated segmentation rectangle are all outside the outer contour; the method comprises the steps of taking a segmentation rectangle as a cutting boundary Clip, taking an inner contour and an outer contour as cutting object subjects, calling a Clip cutting tool, and dividing the annular contour into two independent strip-shaped contours by combining the center point of the inner contour and the dirA direction.
  3. 3. The angle-controlled ring-bar profile split direction-changing scanning straight line path planning method according to claim 2, wherein four vertex coordinates of the split rectangle are determined as follows: if vAB.dot (dirA) > 0, then: p0 = A - _splitRecDelta*dirA - _splitRecDelta* dir; p1 = B + _splitRecDelta* dirA - _splitRecDelta*dir; p2 = B + _splitRecDelta*dirA + _splitRecDelta* dir; p3 = A - _splitRecDelta*dirA + _splitRecDelta*dir; If vAB.dot (dirA) <0, then: p0 = B - _splitRecDelta*dirA - _splitRecDelta*dir; p1 = A + _splitRecDelta*dirA - _splitRecDelta*dir; p2 = A + _splitRecDelta*dirA + _splitRecDelta* dir; p3 = B - _splitRecDelta*dirA + _splitRecDelta*dir。
  4. 4. The angle-controlled ring-bar profile zoned direction-changing scanning straight line path planning method according to claim 1, wherein the dividing each bar profile into a plurality of sub-profiles according to the angle threshold, cutting, comprises the following steps: Traversing each Segment of the bar contour, calculating the projection values of the vertexes of the Segment on dirA and dir, determining the span of the contour in dir direction, namely a minimum span value LayerMin and a maximum span value LayerMax, matching the intersected contour segments for each scan line, and storing the segments as INTERSECTSEGARR arrays; for each scanning line, constructing a segmentation plane through the height value of each scanning line in the dir direction, calculating an intersection point with a matched line segment, recording the line segment serial number of the intersection point and the projection size of the intersection point in the dirA direction, and storing the line segment serial number and the projection size in a pointWithRefValues list after sequencing according to the projection size; the first line segment DELETESEG of the cut rectangle cutting outline is eliminated, and the initial scanning line sequence number startLineNum is calculated through the length of DELETESEG and step; Extracting the first two intersection points from the pointWithRefValues list, finding a corresponding contour line segment INTERSECTSEG, and calculating an included angle between a normal vector vn of the contour line segment INTERSECTSEG and dirA, wherein if the included angle is in the range of [ ANGLELIMIT, ANGLELIMIT +10.0], the two intersection points A, B are used as partition boundaries; acquiring an included angle INTERSECTSEG meeting an angle threshold and the positive direction of the x-axis and determining a new scanning direction newDirA according to the included angle; Constructing a segmentation rectangle according to the point A, B, and calling a clip to cut the current bar profile to obtain two sub-profiles, namely a current profile polyFillData to be filled which stores the current dirA and step and a next profile polySplitData to be cut which stores the new scanning direction newDirA and step; Repeating the above flow, cutting the sub-contours in the contour polySplitData to be cut again until all the sub-contours meet the angle threshold requirement, and outputting multi-partition filling data MultiDirPolysFillData, wherein the dirA, step and contour information of each sub-contour are contained.
  5. 5. The angle-controlled circular-bar contour zoned direction-changing scanning straight line path planning method according to claim 4, wherein the excluding the first line segment DELETESEG of the cut-out rectangular cut-out sub-contour and calculating the starting scan line sequence number startLineNum by DELETESEG length and step comprises: The method comprises the steps of determining that a contour is not split for the first time, entering a branch processing function, and finding out the largest and the next largest contour line segments in the branch processing function by finding out the projection size of line segments of sub-contours on dir vectors; And judging the projected size value of the tail point of the found outline on dir, taking the outline where the tail point of the smaller value is located as the first line segment DELETESEG for intersection elimination, and calculating the intersection scanning line sequence number startLineNum according to the length and step of DELETESEG.
  6. 6. The angle-controlled circular-bar contour zoned direction-changing scanning line path planning method of claim 4, wherein said obtaining the angle INTERSECTSEG meeting the angle threshold with the x-axis forward direction and determining the new scanning direction newDirA from the angle comprises: Calculating the angle1 between INTERSECTSEG and the positive direction of the x axis, which meets the threshold value: if angle1<0, then the new scan direction newDirA is a vector with the start point pointing to the end point of INTERSECTSEG rotated 90 degrees counterclockwise about the z-axis, otherwise rotated 90 degrees clockwise.
  7. 7. The angle-controlled ring-bar profile split direction-changing scanning straight line path planning method according to claim 4, wherein for storing a current profile polyFillData to be filled and a next profile polySplitData to be cut, a storage order is judged by sub-profile center coordinates.
  8. 8. The angle-controlled ring-bar profile zoned direction-changing scanning straight line path planning method according to claim 1, wherein said inwardly biasing each sub-profile according to a bias parameter comprises: For each partition sub-profile, the bias function of the clip is invoked and biased inwardly according to bias parameter_ fillContourOffsetParam.
  9. 9. The angle-controlled circular-bar profile zoned direction-changing scanning straight line path planning method according to claim 7, wherein the bias parameter_ fillContourOffsetParam is set in a range of-0.5 to-0.3, and a negative number indicates inward bias.
  10. 10. A computer system, comprising: one or more processors; a memory storing instructions operable, when executed by the one or more processors, to cause the one or more processors to perform operations comprising the flow of the angle-controlled ring-bar profile partition diversion scan straight line path planning method of any one of claims 1-9.

Description

Angle-controlled annular-strip profile partition turning scanning linear path planning method and system Technical Field The invention relates to the technical field of additive manufacturing, in particular to a path planning technology in an additive manufacturing process, and particularly relates to an angle-controlled annular-strip profile partition direction-changing scanning straight line path planning method and system. Background Additive Manufacturing (AM) has the characteristics of high-efficiency forming, high material utilization rate, high-degree-of-freedom complex structure integrated forming and the like, and is widely applied to equipment manufacturing of key bearing parts such as aerospace, ships, automobiles, bridges, buildings and the like. The laser directional energy deposition technology takes laser as a heat source, melts powder or wire materials at high temperature in a short time, and rapidly cools, stacks and forms along different paths. However, the setting of parameters such as the shape, length, direction, overlap spacing, etc. of the path not only directly affects the surface quality of the formed article, but also determines the thermal cycling pattern during the build-up process, causing different residual stresses to exist between rapid melting and solidification of the material. The traditional filling mode of the unidirectional linear scanning path has the advantages that the forming precision is low at the position with larger contour curvature, the thermal cycle mode in the forming process is single, larger residual stress and deformation are easy to generate under the condition of overlong path, and the phenomena of buckling deformation and even fracture are generated. Disclosure of Invention The invention aims to provide an angle-controlled annular-strip profile partition turning scanning linear path planning method, which is used for optimizing the forming precision in the additive manufacturing process, improving the internal stress, preventing part deformation and improving the forming quality of additive manufacturing by scanning and filling the slice profile partition in a variable direction. According to a first aspect of the present invention, an angle-controlled ring-bar profile zoned direction-changing scanning straight line path planning method is provided, comprising the following steps: Acquiring contour data of a planar annular shape or a strip shape of a slice of the additive manufactured part; If the contour data is an annular contour, splitting the annular contour into two strip-shaped contours; Dividing each bar profile into a plurality of sub-profiles according to an angle threshold, wherein each of the sub-profiles after cutting has an initial scanning direction and a scanning line arrangement direction; Inwards biasing each sub-profile according to the bias parameters; For each biased sub-contour, generating intersection lines of scanning lines and contour line segments according to corresponding initial scanning directions, scanning line arrangement directions and filling interval parameters, sequentially constructing filling paths, and outputting zonal path data of the whole bar-shaped contour; and merging the partition path data of the two bar-shaped outlines to obtain a partition turning scanning filling path of the complete annular outline. As an alternative embodiment, the annular profile is split, and the split is converted into two bar profiles, comprising the following steps: Inputting annular inner and outer contour data, constructing a straight Line, and solving intersection points A, B of the straight Line and the inner and outer contours through dot product relation between adjacent points of the outer contours and normal vectors of the Line; Calculating an inner contour center point, combining the intersection point A, B with dirA, dir and_ SPLITRECDELTA parameters to construct a segmentation rectangle, and determining vertex coordinates of the segmentation rectangle according to the positive and negative properties of vAB.dot (dirA), wherein four vertices P0, P1, P2 and P3 of the generated segmentation rectangle are all outside the outer contour; the method comprises the steps of taking a segmentation rectangle as a cutting boundary Clip, taking an inner contour and an outer contour as cutting object subjects, calling a Clip cutting tool, and dividing the annular contour into two independent strip-shaped contours by combining the center point of the inner contour and the dirA direction. As an alternative embodiment, each bar profile is segmented according to an angle threshold and cut into a plurality of sub-profiles, comprising the steps of: Traversing each Segment of the bar contour, calculating the projection values of the vertexes of the Segment on dirA and dir, determining the span of the contour in dir direction, namely a minimum span value LayerMin and a maximum span value LayerMax, matching the intersected contour segments for