Laser deposition forming method, electronic device, and storage medium

Abstract

The application discloses a laser deposition forming method, an electronic device and a storage medium, relates to the field of additive manufacturing technology, and comprises the following steps: obtaining a three-dimensional model of a rotary body, performing slice processing on the three-dimensional model of the rotary body to obtain a plurality of slice layers with different slice directions, the slice direction being a direction perpendicular to the tangential direction of a skeleton line of the three-dimensional model of the rotary body; dividing forming tracks in the slice layers; determining attitude parameters corresponding to the slice layers; controlling a laser cladding head to reach an attitude corresponding to the slice layer according to the attitude parameters, then starting a laser, depositing and forming the forming tracks, and until the forming of all the forming tracks is completed, a rotary body part is obtained. The application realizes the technical effect of improving the forming quality of the rotary body part by changing the direction of the slice and adjusting the attitude of the laser cladding head.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of additive manufacturing technology, in particular to a laser deposition forming method, an electronic device and a storage medium. BACKGROUND

[0002] The laser deposition additive manufacturing technology based on robots has outstanding advantages in many additive manufacturing technologies due to its low heat input, high flexibility, high forming precision and other characteristics, and has been widely concerned by domestic and foreign experts, scholars, scientific research institutions and the industry, and has been applied in the field of high-end equipment parts manufacturing such as aerospace. Laser deposition technology has the characteristics of small molten pool and fast solidification rate, so it has obvious advantages in forming inclined wall and even cantilever features.

[0003] Rotary feature parts are widely used in industrial fields, and usually have inclined wall features with continuously changing cross-sectional radii. At present, additive manufacturing is mainly in the form of 2+1D, which generates a profile by horizontal slicing in the vertical direction, and then forms layer by layer. For rotary parts with inclined wall features, the upper profile of the forming sequence is often larger in range than the lower profile of the forming sequence, and there is a suspended part. When the suspended length is large, it will cause molten pool flow, size loss, and even failure to form a weld, and damage the surface quality, that is, the forming quality of the rotary part is poor. SUMMARY

[0004] The main purpose of the present application is to provide a laser deposition forming method, an electronic device and a storage medium, which aims to solve the problem of poor forming quality of the current additive manufacturing method for forming rotary parts.

[0005] To achieve the above-mentioned purpose, the present application provides a laser deposition forming method, which comprises:

[0006] Obtaining a rotary three-dimensional model, performing direction-changing slicing processing on the rotary three-dimensional model to obtain a plurality of slice layers with different slicing directions, the slicing direction being a direction perpendicular to the tangential direction of the skeleton line of the rotary three-dimensional model;

[0007] Dividing the slice layer into forming tracks;

[0008] Determining the attitude parameters corresponding to the slice layer;

[0009] According to the attitude parameters, controlling the laser cladding head to reach the attitude corresponding to the slice layer, and then turning on the laser to deposit and form the forming track, until the forming of all forming tracks is completed, to obtain a rotary part.

[0010] Optionally, the step of performing slicing processing on the rotary three-dimensional model to obtain a plurality of slice layers with different slicing directions comprises:

[0011] converting the three-dimensional model of the rotary body into a two-dimensional contour, and determining a skeleton line of the two-dimensional contour;

[0012] inserting a plurality of discrete points on the skeleton line, calculating a tangential vector of the discrete points along the skeleton line, and calculating a slicing direction of the slice layer according to the tangential vector;

[0013] slicing the two-dimensional contour by a plane passing through the discrete points and consistent with the slicing direction, and the intersection of the plane and the two-dimensional contour being the slice layer.

[0014] Optionally, the step of determining the skeleton line of the two-dimensional contour comprises:

[0015] triangulating an interior of the two-dimensional contour to obtain a plurality of adjacent triangles;

[0016] according to a topological relationship between the plurality of triangles, sequentially connecting a bottom side of a terminal triangle and a midpoint of each adjacent common side to construct the skeleton line.

[0017] Optionally, the step of calculating the tangential vector of the discrete points along the skeleton line comprises:

[0018] determining a vertex type of the discrete point;

[0019] if the discrete point is an intersection point of the skeleton line and the triangle, determining adjacent edges of the intersection point, and performing vector addition according to a direction and a length of the adjacent edges to obtain the tangential vector;

[0020] if the discrete point is not the intersection point of the skeleton line and the triangle, determining an adjacent end point of the discrete point, and performing vector addition according to a tangential direction of the end point and a distance between the discrete point and the end point to obtain the tangential vector.

[0021] Optionally, the step of dividing the forming trajectory in the slice layer comprises:

[0022] obtaining a number of trajectories and a trajectory interval of the slice layer;

[0023] if the number of trajectories is odd, inserting the discrete point as a trajectory point into the forming trajectory, and setting an initial offset to be equal to the trajectory interval;

[0024] if the number of trajectories is even, setting the initial offset to be equal to a preset length;

[0025] offsetting the discrete point along the slicing direction according to the initial offset and the trajectory interval to obtain the forming trajectory.

[0026] Optionally, the step of determining the pose parameter corresponding to the slice layer comprises:

[0027] obtaining a target direction vector, and determining a deflection direction parameter according to an included angle between the target direction vector and the tangent vector;

[0028] combining the height coordinate of the discrete point with the deflection direction parameter to obtain the pose parameter.

[0029] Optionally, the forming tracks are multiple, and the forming tracks have a sequence in the deposition forming process, and the step of turning on the laser and depositing and forming the forming track comprises:

[0030] taking a first forming track as a target forming track, and taking a starting forming point of the first forming track as a target forming point;

[0031] fixing the laser cladding head, turning on the laser, controlling a rotary workbench cooperating with the laser cladding head to rotate a preset angle, and depositing and forming the target forming track from the target forming point;

[0032] determining a starting forming point of a next forming track of the target forming track according to a track-to-track angle increment and a layer-to-layer angle increment, updating the target forming point to the starting forming point of the next forming track of the target forming track, updating the target forming track to the next forming track of the target forming track, and returning to execute the step of fixing the laser cladding head, turning on the laser, controlling the rotary workbench cooperating with the laser cladding head to rotate the preset angle, and depositing and forming the target forming track from the target forming point.

[0033] Optionally, after the step of fixing the laser cladding head, the method further comprises:

[0034] obtaining an advance motion length, and calculating an advance angle corresponding to the advance motion length;

[0035] controlling the rotary workbench to rotate the advance angle, and executing the step of turning on the laser, controlling the rotary workbench cooperating with the laser cladding head to rotate the preset angle, and depositing and forming the target forming track from the target forming point.

[0036] In addition, to achieve the above object, the application further provides an electronic device, which comprises a memory, a processor, and a laser deposition forming program stored in the memory and capable of running on the processor, and the laser deposition forming program is configured to implement the steps of the laser deposition forming method as described above.

[0037] In addition, to achieve the above object, the application further provides a computer readable storage medium, wherein a laser deposition forming program is stored on the computer readable storage medium, and the laser deposition forming program realizes the steps of the laser deposition forming method as described above when executed by a processor.

[0038] The application obtains a three-dimensional model of a rotary body, performs slice processing on the three-dimensional model of the rotary body to obtain a plurality of slice layers with different slice directions, the slice direction being a direction perpendicular to the tangential direction of the skeleton line of the three-dimensional model of the rotary body, divides forming tracks in the slice layers, determines attitude parameters corresponding to the slice layers, controls a laser cladding head to reach an attitude corresponding to the slice layer according to the attitude parameters, then starts a laser, deposits and forms the forming tracks, and finally completes the formation of all the forming tracks to obtain a rotary body part. In the application, the slice processing mode is applied to a rotary body with varying cross sections, the slice direction of the slice layer is no longer a horizontal direction but a direction perpendicular to the tangential direction of the skeleton line, so as to reduce the overhanging length between the slice layers, and the laser cladding head is combined with the change of the slice direction of the slice layer to perform attitude transformation, effectively reducing the probability of molten pool flow, reducing the step effect, and improving the forming quality. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 A structural schematic diagram of an electronic device for a hardware running environment involved in an embodiment of the application;

[0040] Figure 2 A flowchart of a laser deposition forming method according to a first embodiment of the application;

[0041] Figure 3 A schematic diagram of a three-dimensional model of a rotary body involved in the laser deposition forming method of the application;

[0042] Figure 4a A schematic diagram of a two-dimensional contour involved in the laser deposition forming method of the application;

[0043] Figure 4b A schematic diagram of a two-dimensional contour involved in the laser deposition forming method of the application; Figure 4a A schematic diagram of a skeleton line of a two-dimensional contour;

[0044] Figure 5a A schematic diagram of contour triangulation involved in the laser deposition forming method of the application;

[0045] Figure 5b A schematic diagram of constructing a skeleton line of a two-dimensional contour in the laser deposition forming method of the application; Figure 5a A schematic diagram of constructing a skeleton line of a two-dimensional contour in the laser deposition forming method of the application;

[0046] Figure 6 A schematic diagram of the distribution position of a discrete point involved in the laser deposition forming method of the application;

[0047] Figure 7 A schematic diagram of a slice along a skeleton line involved in the laser deposition forming method of the present application;

[0048] Figure 8a A schematic diagram of a forming track with a track number of 2 involved in the laser deposition forming method of the present application;

[0049] Figure 8b A schematic diagram of a forming track with a track number of 3 involved in the laser deposition forming method of the present application;

[0050] Figure 9 A schematic diagram of a track key point involved in the laser deposition forming method of the present application.

[0051] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0052] It should be understood that the specific embodiments described herein merely exemplify the present application and do not limit the present application.

[0053] Reference Figure 1 , Figure 1 A schematic diagram of an electronic device structure of a hardware running environment involved in the embodiment scheme of the present application.

[0054] As Figure 1 shown, the electronic device can include a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. The communication bus 1002 is used to realize the connection and communication between the components. The user interface 1003 can include a display, an input unit such as a keyboard, and can also include a standard wired interface, a wireless interface. The network interface 1004 can optionally include a standard wired interface, a wireless interface (such as a wireless fidelity (WIreless-FIdelity, WI-FI) interface). The memory 1005 can be a high-speed random access memory (RAM) memory, or a stable non-volatile memory (Non-Volatile Memory, NVM), such as a magnetic disk memory. The memory 1005 can also be a storage device independent of the aforementioned processor 1001.

[0055] Those skilled in the art can understand that the structure shown in the Figure 1 above does not constitute a limitation on the electronic device, and can include more or fewer components than the diagram, or combine certain components, or different component arrangements.

[0056] As shown in Figure 1 , the memory 1005 as a storage medium can include an operating system, a network communication module, a user interface module and a laser deposition forming program.

[0057] In Figure 1 the electronic device, the network interface 1004 is mainly used for data communication with other devices; the user interface 1003 is mainly used for data interaction with the user; the processor 1001 and the memory 1005 in the electronic device of the present application can be arranged in the electronic device, and the electronic device calls the laser deposition forming program stored in the memory 1005 through the processor 1001, and executes the laser deposition forming method provided by the embodiment of the present application.

[0058] The embodiment of the present application provides a laser deposition forming method, referring to Figure 2 , Figure 2 is a flowchart of a first embodiment of a laser deposition forming method of the present application.

[0059] In this embodiment, the laser deposition forming method comprises:

[0060] Step S10, obtaining a three-dimensional model of a rotary body, performing slicing processing on the three-dimensional model of the rotary body to obtain a plurality of slice layers with different slice directions, the slice direction being a direction perpendicular to the tangential direction of the skeleton line of the three-dimensional model of the rotary body;

[0061] The three-dimensional model of the rotary body refers to a three-dimensional model simulating an actual rotary body part according to a certain proportion, which can be a model in STL (S Tereo Lithography, stereolithography) format. The rotary body refers to a three-dimensional shape formed by rotating around an axis. The slice layer can be regarded as the intersection of a plane and a three-dimensional model, the intersection of the plane and the three-dimensional model, and the direction of the plane is the slice direction. The slicing process can be regarded as slicing the three-dimensional model using the slice plane to obtain the slice layer. In this embodiment, the variable direction slicing method is adopted, and the variable direction slicing process can be regarded as the process of using slice planes with different directions to intersect with the three-dimensional model of the rotary body. The directions of the plurality of slice planes are different, so the slice layers have different slice directions. The skeleton line can be regarded as an object representation using a thin curve consistent with the original shape connectivity and topological structure as an ideal expression. Select an arbitrary point on the skeleton line, and draw a tangent line of the point along the skeleton line, then the slice direction is perpendicular to the direction of the tangent line, and the slice layer is also perpendicular to the direction of the tangent line.

[0062] Step S20, dividing a forming track in the slice layer;

[0063] The forming trajectory can be regarded as a trajectory experienced by the laser cladding head in the laser deposition forming process. The slice layer has a certain thickness, and the width of the weld formed after the laser cladding head is turned on is limited, and usually a plurality of forming trajectories are included in the slice layer. The embodiment does not make specific limitation on the implementation manner of dividing the forming trajectory, for example, the forming trajectories can be arranged in a uniform distribution manner within the thickness range of the slice layer.

[0064] In step S30, the attitude parameter corresponding to the slice layer is determined.

[0065] The attitude parameter can be regarded as a parameter related to the attitude of the laser cladding head required to be reached when depositing the slice layer. The laser cladding head is located at the end of the robot, and its attitude in space can be controlled by rotating the rotating shaft. Since the slice direction of the slice layer is different, each slice layer can correspond to different laser cladding head attitude parameters. The embodiment does not make specific limitation on the implementation manner of determining the attitude parameter, for example, an included angle can be formed by the slice direction and the pointing direction of the laser cladding head, and the angle range of the included angle is controlled to be within a preset range, so as to determine the attitude parameter.

[0066] In step S40, the laser cladding head is controlled to reach the attitude corresponding to the slice layer according to the attitude parameter, and then the laser is turned on to deposit and form the forming trajectory, until the formation of all forming trajectories is completed, and a rotary part is obtained.

[0067] The laser cladding head is a forming part of the additive manufacturing equipment, and after the laser is turned on, the cladding head melts the metal material to form a weld. Each slice layer can correspond to different laser cladding head attitudes. The embodiment adopts a laser deposition forming method based on a robot, and the laser cladding head located at the end of the robot can reach different attitudes through the mechanical shaft. After the formation of each slice layer is completed, the laser cladding head can be transformed in attitude and switched to the attitude corresponding to the next slice layer. The attitude transformation can be regarded as a change in the rotating state of the rotating shaft of the laser cladding head, so as to change the process of the attitude of the laser cladding head. The laser cladding head prints according to the forming trajectory, and after printing is completed, a rotary part corresponding to the rotary three-dimensional model is obtained.

[0068] In this embodiment, a three-dimensional model of a rotating body is obtained, and the model is sliced ​​to obtain multiple slice layers with different slicing directions. The slicing direction is perpendicular to the tangential direction of the skeleton line of the three-dimensional model of the rotating body. Forming trajectories are divided within the slice layers. Attitude parameters corresponding to each slice layer are determined. Based on the attitude parameters, the laser cladding head is controlled to reach the attitude corresponding to the slice layer, and then the laser is activated to deposit and form the forming trajectory until all forming trajectories are completed, resulting in a rotating body part. In this invention, the slicing method is applied to rotating bodies with varying cross-sections. The slicing direction of the slice layers is no longer horizontal but perpendicular to the tangential direction of the skeleton line, reducing the overhang length between slice layers. Combined with the laser cladding head's attitude change following the changes in the slicing direction of the slice layers, the probability of melt pool flow is effectively reduced, the step effect is minimized, and the forming quality is improved.

[0069] Furthermore, in a second embodiment of the laser deposition forming method of the present invention, the method includes:

[0070] Step S11: Convert the three-dimensional model of the rotating body into a two-dimensional contour and determine the skeleton line of the two-dimensional contour;

[0071] A two-dimensional contour can be viewed as a two-dimensional shape obtained by slicing a three-dimensional model of revolution with a plane passing through the axis. Figure 3 This is a schematic diagram of a three-dimensional model of a solid of revolution, such as... Figure 3 As shown, the 3D model of the solid of revolution consists of a cylinder at the bottom and a sphere at the top. With the center of the cylinder's base as the origin, a three-axis coordinate system (XYZ) can be established in space, with the central axis being the Y-axis. The YOZ plane intersects the model, and its normal vector is... The set of three-dimensional models of the rotating body is obtained as Ω={p i (0,y,z),i=0,1,…,n-1}. Transform Ω into a two-dimensional planar contour S={p i For the contour S (y, z), i = 0, 1, ..., n-1, calculated in a two-dimensional coordinate system, the contour S intersects the Y-axis, and the contour within the positive X-axis interval is retained, i.e., p i x≥0.

[0072] Figure 4a This is a schematic diagram of a two-dimensional contour. 101 represents the two-dimensional contour. By rotating this two-dimensional contour by one revolution, a three-dimensional model of the solid of revolution can be obtained. This two-dimensional contour retains the shape characteristics of the three-dimensional model of the solid of revolution. Figure 4b for Figure 4a This is a schematic diagram of the skeleton lines of a 2D contour. 102 represents the skeleton line, and the shape characteristics of the skeleton line are consistent with the 2D contour. First, the center of the arc portion in the 2D contour can be calculated. Then, the radius of the arc can be taken between the corresponding radii of the inner and outer contour lines. Finally, the position of the skeleton line can be determined, thus defining the skeleton line.

[0073] In one feasible implementation, the step of determining the skeleton lines of the two-dimensional contour may include:

[0074] Step S111: Triangulate the interior of the two-dimensional contour to obtain multiple adjacent triangles;

[0075] Triangulation can be viewed as a process of filling the interior of a two-dimensional contour using triangle-like shapes. During the filling process, each triangle is adjacent to at least one other triangle. Adjacent triangles share a common edge. Triangulation can be performed using the Delaunay algorithm. Therefore, triangulating the interior of contour S yields a set T = {t}. i (p a p b p c ), i∈[0, u); a, b, c∈[0, n), a≠b, b≠c, a≠c}. Figure 5a This is a schematic diagram of contour triangulation, where 103 represents a triangle, such as... Figure 5a As shown, the triangles obtained after triangulation are not concyclic, the terminal triangles have one common side, and the inner triangles have two common sides.

[0076] Step S112: Based on the topological relationship between the multiple triangles, the base of the end triangle and the midpoint of each adjacent common edge are connected in sequence to construct the skeleton line.

[0077] Based on the topological relationships of triangles, we can start traversing from the bottom triangle, connecting the midpoints of two adjacent common sides in sequence to construct the straight skeleton line M = {m} of the contour S. i (y, z), i = 0, 1, ..., N-1}. The choice of the terminal triangle can be determined by topological relationships, for triangle t i Check its three adjacent triangles. If there is only one adjacent triangle, it is the terminal triangle. Take the triangle with the smallest vertex Y value as the bottom triangle and the bottom edge. Figure 5b In order to be in Figure 5a A schematic diagram of the skeleton lines constructed from the two-dimensional contours. Figure 5b In the diagram, the dashed line 102 represents the skeleton line. Triangles ABC and DEF are the terminal triangles. H is the midpoint of side AB, S is the midpoint of side BC, and T is the midpoint of side DF. By extending the two terminal skeleton sides MS and NT, we can determine that the extension lines intersect sides AB and EF respectively. Connecting the midpoints of AB and EF will give us the complete skeleton line.

[0078] By constructing skeleton lines by connecting the midpoints after triangulation, and given a sufficient number of triangles, straight lines can be used to represent curves, preserving the curvature of the skeleton lines and simplifying the calculation process.

[0079] Step S12, insert a plurality of discrete points on the skeleton line, calculate the tangential vector of the discrete points along the skeleton line, and calculate the slicing direction of the slice layer according to the tangential vector;

[0080] The insertion position of the discrete point can be determined according to the input printing layer thickness h, refer to Figure 6 , Figure 6 is a schematic diagram of the distribution position of a discrete point, 104 represents a discrete point, and the discrete point q is inserted along the skeleton line starting point m0 according to the curve length increment h. The position of the discrete point in the spatial coordinate system can be used as a reference for the position of the slice layer. The process of inserting the discrete point can refer to the following steps.

[0081] Step a, let the length value l m = 0, start from m o , calculate the distance d i = dist(m i-1 , m i ) of two adjacent points in the skeleton line, i ∈ [1, N-1). The initial i = 0, the length l m = d1, and the slice layer height h s = 0.

[0082] Step b, when l m > h s , insert a slice point, the calculation formula is q = m i + v i-1，i *(l m -h s ), and the vector v i-1，i is a unit vector from point m i to m i-1 . Then increase a slice layer thickness, h s = h s + h, and repeat the step.

[0083] Step c, when l m < h s , let i = i + 1, l m = l m + d i , return to step b until all vertices of the skeleton are retrieved.

[0084] The tangential vector of the discrete point along the skeleton line points to the direction perpendicular to the slicing direction of the slice layer. After the tangential vector is calculated, the slicing direction can be obtained by adding or subtracting an angle of 90°.

[0085] Step S13, slice the two-dimensional contour through the discrete point and in the same direction as the slicing direction, and the intersection of the plane and the two-dimensional contour is the slice layer.

[0086] Figure 7 This is a schematic diagram of slicing along a skeleton line. Figure 7 The dashed line 105 represents a slice layer. Slice layer 105 passes through discrete point 104, and the slicing direction of the slice layer is perpendicular to the tangential vector direction of this discrete point. The tangential vector v along the skeleton line from discrete point q is calculated; then {q, v} stores the position and orientation information of the slice layer, respectively. Finally, the set of slice layers Q = {q} can be obtained. i v i , i = 0, 1, ..., w-1}.

[0087] In one feasible implementation, the step of calculating the tangential vector of the discrete point along the skeleton line may include:

[0088] Step S131: Determine the vertex type of the discrete points;

[0089] from Figure 6 As can be seen, the skeleton line and the triangle intersect at points, and the distance between two intersection points is a line segment. Discrete points may coincide with the intersection points or lie outside of them. The skeleton line's starting point m0 ​​and ending point m... N-1 The tangent vector is in the same direction as the edge of the skeleton, i.e., v m,0 =m1-m0; v m,N-1 =m N-1 -m N-2 .

[0090] Step S132: If the discrete point is the intersection of the skeleton line and the triangle, then determine the adjacent edge of the intersection point, and perform vector summation based on the direction and length of the adjacent edge to obtain the tangential vector:

[0091] When the discrete point and the intersection point coincide, the direction of the tangential vector of the discrete point is determined by its two adjacent edges. In this case, the tangential vector can be calculated as follows.

[0092]

[0093] Side e i (m i m i-1 The length of ) is |e i |, the unit direction vector is v i,i-1 ;side e i+1 (m i+1 m i The length of ) is |e i+1 |, the unit direction vector is v i+1，j .

[0094] Step S133, if the discrete point is not the intersection point of the skeleton line and the triangle, determining an end point adjacent to the discrete point, and performing vector addition according to the tangent direction of the end point and the distance between the discrete point and the end point to obtain the tangent vector.

[0095] In the case that the position of the discrete point and the intersection point are not coincident, that is, for the discrete point falling on the skeleton edge e i , the tangent vector of the section point q i is controlled by the tangent directions of the two end points of the edge. The end point refers to the intersection point between the skeleton line and the triangle. At this time, the calculation method of the tangent vector can be as follows.

[0096]

[0097] The variable dist(m i-1 , q i ) is the distance from the section point to the end point.

[0098] In the embodiment, the skeleton line of the two-dimensional contour is constructed through the triangulation processing, the discrete point is inserted along the skeleton line, the position of the section layer is calculated according to the tangent vector of the discrete point along the skeleton line direction, the variable-direction sectioning of the revolution body with varying cross section is realized, and the calculation process of the section layer position and the section direction is simple.

[0099] Further, in the third embodiment of the laser deposition forming method, the method comprises:

[0100] Step S21, acquiring the number of trajectories of the section layer and the trajectory spacing;

[0101] The trajectory spacing can be regarded as the distance between the forming trajectories. The number of trajectories c and the trajectory spacing d can be obtained by receiving external input. Different trajectory calculation methods can be used for different numbers of trajectories.

[0102] Step S22, if the number of trajectories is odd, inserting the discrete point as a trajectory point into the forming trajectory, and setting the initial offset to be equal to the trajectory spacing;

[0103] In the case that the number of trajectories c is odd, there is a central trajectory, and the other trajectories can be symmetrically distributed with the central trajectory as the axis, so that the q i can be inserted into the trajectory set path i ={q i}, the initial offset d0 is set to be equal to the trajectory spacing d, and c is set to be equal to c-1.

[0104] Step S23, if the number of trajectories is even, setting the initial offset to be equal to a preset length;

[0105] In the case that the number of trajectories is even, there is no center trajectory, and all trajectories are symmetrically distributed around a virtual axis, the initial offset d0 can be a preset length, which can be

[0106] In step S24, the discrete points are offset in the slicing direction according to the initial offset and the trajectory spacing, and the forming trajectory is obtained.

[0107] v i The vertical direction, i.e., the slicing direction, is u j q i Along the u j and -u j directions, the offset points are calculated and sequentially inserted into the trajectory set, which can be represented as follows.

[0108]

[0109] Each point represents a circular trajectory, which can be sorted from inside to outside, and when c is even, q i is not inserted into the trajectory. The trajectory set represents the forming trajectory.

[0110] In this embodiment, the forming trajectory is reasonably arranged in the slicing layer according to the input number of trajectories and trajectory spacing, which facilitates subsequent printing according to the forming trajectory.

[0111] Further, in the fourth embodiment of the laser deposition forming method, the method comprises:

[0112] In step S31, a target direction vector is obtained, and a deflection direction parameter is determined according to the included angle between the target direction vector and the tangent vector.

[0113] The target direction vector can be a hypothetical vector, for example, v’=(0, 1). The deflection direction parameter can be regarded as a parameter related to the direction in which the laser cladding head should be deflected during laser deposition. If the tangent vector v i (x, y), the deflection direction parameter wherein δ=-1 represents clockwise deflection of the cladding head around the X axis, and δ=1 represents counterclockwise deflection of the cladding head around the X axis.

[0114] In step S32, the height coordinate of the discrete point is combined with the deflection direction parameter to obtain the pose parameter.

[0115] The pose parameter can include a deflection angle parameter of the laser cladding head and the deflection direction parameter. The deflection angle parameter can be calculated using the following formula.

[0116]

[0117] wherein |v i | represents the length of the vector, v i .y represents the y coordinate of the vector, i.e. the height coordinate.

[0118] In the embodiment, the angle and direction of the laser cladding head that need to be deflected corresponding to the slice layer are calculated according to the direction of the tangential vector, so that the posture of the laser cladding head can be adjusted according to the generatrix curvature variation law of the part of the revolution body, and is consistent with the direction of the inclined wall of the printing position, the molten pool flow and the step effect are reduced, the near-net forming of the variable cross-section revolution body without support is realized, and the forming precision is improved.

[0119] Further, in a fifth embodiment of the laser deposition forming method, the method comprises:

[0120] In step S41, the first forming track is taken as a target forming track, and the starting forming point of the first forming track is taken as a target forming point.

[0121] Each slice layer can contain a plurality of forming tracks, and the forming tracks have a forming sequence. In a two-dimensional contour, the forming point in the slice layer can represent a circumferential track in a three-dimensional space. The starting forming point of the first forming track can be selected arbitrarily. The first forming track can be the forming track closest to the outside or closest to the inside in the bottommost slice layer.

[0122] In step S42, the laser cladding head is fixed, the laser is turned on, the rotary workbench cooperating with the laser cladding head is controlled to rotate by a preset angle, and the target forming track is deposited and formed from the target forming point.

[0123] In the embodiment, the laser cladding head is fixed, and the rotary workbench is rotated. In a two-dimensional contour, each track point can correspond to a circumferential track, and theoretically, the rotary workbench can complete the formation of a circumferential track after one rotation. The preset angle can be 360°.

[0124] In another embodiment, the length L of the track head and tail overlap can also be given, so that the workpiece rotation angle is slightly larger than a full circle when the track is formed, that is, the preset angle is wherein r k is the radius of the current track, that is, the X coordinate of the track point p k .

[0125] In a feasible embodiment, after the step of fixing the laser cladding head, the method can further comprise:

[0126] Step S411, obtain the pre-movement length, calculate the pre-movement length corresponding pre-angle;

[0127] The head-high tail-low phenomenon of the weld bead can also be improved in a manner of eliminating the problem of accelerating from zero of the printing start stage device. Obtain the pre-movement length s prev The pre-angle corresponding to the pre-movement length can be calculated as

[0128] Step S412, control the rotary table to rotate the pre-angle, execute the step of starting the laser, and control the rotary table cooperating with the laser cladding head to rotate a preset angle, to deposit and form the target forming track starting from the target forming point.

[0129] Before the current track printing starts, the worktable is actually rotated to an angle φ ki -φ prev Then the worktable is rotated by φ prev Immediately after the laser is started, the printing is continued in the same direction, the starting printing speed is ensured to be the given linear speed, and the head bulge caused by the acceleration period is reduced.

[0130] Step S43, determine the starting forming point of the next forming track of the target forming track according to the inter-track angle increment and the inter-layer angle increment, update the target forming point to the starting forming point of the next forming track of the target forming track, update the target forming track to the next forming track of the target forming track, and return to execute the step of fixing the laser cladding head, controlling the rotary table cooperating with the laser cladding head to rotate a preset angle, and depositing and forming the target forming track starting from the target forming point.

[0131] The printing of different tracks can also adopt a printing manner in which the starting rotation angle is staggered. For a given inter-track angle increment and an inter-layer angle increment The starting angle corresponding to each track is i is the layer number, and k is the track sequence number of the current layer. The starting forming point of the next forming track can be determined according to the starting angle, and the next forming track can also be formed in a manner of fixing the position of the laser cladding head and rotating the rotary table.

[0132] In this embodiment, the combination of the track head-tail overlap, the inter-track and inter-layer angle increment, and the pre-movement can improve the forming quality of the head-tail joint of the whole circular weld bead.

[0133] Further, in the sixth embodiment of the laser deposition forming method, the printing is as follows Figure 3The process of creating the 3D model of the solid of revolution shown is explained. The 3D model of the solid of revolution consists of a cylinder and a sphere, with the center of the cylinder's base at the origin. By intersecting the model with the YOZ plane, the vertical cross-sectional profile of the part can be obtained. Taking the positive X-axis, as shown... Figure 4a As shown. A triangulation algorithm, such as the Delaunay algorithm, is used to triangulate the interior of the contour, as... Figure 5a As shown. Based on topological relationships, triangle ABC is chosen as the base triangle. Starting from the midpoint S of the common side BC, the midpoints of each side are connected sequentially until the midpoint T of side DF, thus obtaining the internal skeleton line. Then, the two end skeleton sides MS and NT are extended outwards, and it can be determined that the extended lines intersect sides AB and EF respectively. Therefore, connecting the midpoints H and G of AB and EF yields the complete skeleton line, as shown. Figure 5b As shown. Starting from point H at the end of the skeleton line, discrete points are inserted according to the given slice layer thickness h. Following the laser cladding process, a layer thickness of 0.4mm-1.5mm can generally be given. For ease of display, slices are cut with h = 20mm, as shown... Figure 6 The solid circles shown represent the location points of the slice layers. Calculate the tangential vectors of the skeleton line vertices and slice points. Then, given the trajectory spacing d = 1.5 and the number of trajectories c = 2 and c = 3 respectively, generate the trajectories as follows: Figure 8a The circle shown is the forming trajectory when c=2, and 106 represents the circumference trajectory, as shown. Figure 8b The circle shown is the forming trajectory when c=3, and 106 represents the circular trajectory. When the number of trajectories is odd, there exists a trajectory that passes through the slice position point.

[0134] During the printing process, the overlap length at both ends can be set to 3mm, the advance movement length to 5mm, and the starting angle φ. init =Starting from 0°, the angle increment φ between trajectories path =33°, inter-story angle increment φ layer =57°, calculate the starting print position for different trajectories. Key points on the trajectory are as follows: Figure 9 As shown, point A is the position of the laser cladding head, S is the starting point of the trajectory printing, and E is the ending point of the printing. The offset between the two indicates an overlapping area r. Arrow V indicates the printing direction. Point P is the advance movement position, with arc lengths SP = 5mm and SE = 3mm. Actual printing is achieved by rotating the worktable. After the robot's end effector (i.e., the cladding head) moves to point A and remains stationary, the worktable first rotates clockwise to an absolute angle φ. c =∠POA, then perform incremental motion, continue to rotate clockwise at the preset printing speed by an angle Δφ =∠SOA -∠POA, then turn on the laser, and simultaneously rotate by an angle Δφ = 360 +∠EOA -∠SOA to complete the printing of this trajectory, and continue to the next trajectory.

[0135] The embodiment of the present application also provides an electronic device, which comprises a memory, a processor and a laser deposition forming program stored in the memory and executable on the processor, and the laser deposition forming program is configured to implement the steps of the laser deposition forming method as described above. The specific implementation of the electronic device of the embodiment of the present application is described above in the laser deposition forming method, and will not be repeated here.

[0136] The embodiment of the present application also provides a computer readable storage medium, which stores a laser deposition forming program, and the laser deposition forming program is executed by a processor to implement the steps of the laser deposition forming method as described above. The specific implementation of the computer readable storage medium of the embodiment of the present application is described above in the laser deposition forming method, and will not be repeated here.

[0137] It should be noted that in this document, the term "comprising" or "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or further includes elements inherent to such a process, method, article or system. Without more limitations, the element defined by the statement "comprising a" does not exclude the presence of another identical element in the process, method, article or system including the element.

[0138] The serial numbers of the above embodiments of the present application are only for description, and do not represent the advantages and disadvantages of the embodiments.

[0139] Through the above description of the embodiments, those skilled in the art can clearly understand that the above-mentioned embodiment method can be realized by means of software and necessary general hardware platform, of course, it can also be realized by hardware, but in many cases, the former is a better embodiment. Based on such understanding, the technical solutions of the present application can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes a plurality of instructions for making a terminal device (which can be a mobile phone, computer, server, or network device, etc.) execute the method described in each embodiment of the present application.

[0140] The above is only the preferred embodiment of the present application, and does not limit the patent scope of the present application, and any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied to other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A laser deposition forming method, characterized in that, The laser deposition forming method includes the following steps: Obtain a three-dimensional model of the solid of revolution, convert the three-dimensional model of the solid of revolution into a two-dimensional contour, and perform triangulation processing on the interior of the two-dimensional contour to obtain multiple adjacent triangles; Based on the topological relationship between the multiple triangles, the base of the end triangle and the midpoint of each adjacent common edge are connected in sequence to construct the skeleton line; Insert multiple discrete points along the skeleton line and determine the vertex type of the discrete points; If the discrete point is the intersection of the skeleton line and the triangle, then the adjacent edge of the intersection point is determined, and the tangential vector is obtained by vector summation based on the direction and length of the adjacent edge; If the discrete point is not the intersection of the skeleton line and the triangle, then the endpoint adjacent to the discrete point is determined, and the tangential vector is obtained by vector summation based on the tangential direction of the endpoint and the distance between the discrete point and the endpoint. Calculate the slicing direction of the slice layer based on the tangential vector; The two-dimensional contour is sliced ​​by a plane passing through the discrete points and consistent with the slicing direction. The intersection of the plane and the two-dimensional contour is the slice layer. The slicing direction is perpendicular to the tangential direction of the skeleton line of the three-dimensional model of revolution. The forming trajectory is divided in the slice layer; Determine the attitude parameters corresponding to the slice layer; The laser cladding head is controlled to reach the posture corresponding to the slice layer according to the posture parameters, and then the laser is turned on to deposit and form the forming trajectory until the forming of all the forming trajectories is completed, and a rotating part is obtained.

2. The laser deposition forming method as described in claim 1, characterized in that, The step of dividing the forming trajectory in the slice layer includes: Obtain the number of trajectories and the trajectories spacing of the slice layer; If the number of trajectories is odd, then the discrete points are used as trajectory points and inserted into the formed trajectory, and the initial offset is set to be equal to the trajectory spacing. If the number of trajectories is even, then set the initial offset to a preset length; Based on the initial offset and the trajectory spacing, the discrete points are offset along the slice direction to obtain the shaped trajectory.

3. The laser deposition forming method as described in claim 1, characterized in that, The step of determining the pose parameters corresponding to the slice layer includes: Obtain the target direction vector, and determine the deflection direction parameter based on the angle between the target direction vector and the tangential vector; The attitude parameters are obtained by combining the height coordinates of the discrete points with the deflection direction parameters.

4. The laser deposition forming method according to any one of claims 1-3, characterized in that, The forming trajectory is multiple, and the forming trajectory has a sequential order during the deposition forming process. The step of activating the laser and depositing the forming trajectory includes: The first forming trajectory is taken as the target forming trajectory, and the starting forming point of the first forming trajectory is taken as the target forming point. Fix the laser cladding head, turn on the laser, and control the rotary table that cooperates with the laser cladding head to rotate by a preset angle to deposit and form the target forming trajectory starting from the target forming point; The starting point of the next forming trajectory of the target forming trajectory is determined based on the angle increment between trajectories and the angle increment between layers. The target forming point is updated to the starting point of the next forming trajectory of the target forming trajectory. The target forming trajectory is updated to the next forming trajectory of the target forming trajectory. The process returns to the step of fixing the laser cladding head, controlling the rotary table cooperating with the laser cladding head to rotate by a preset angle, and depositing and forming the target forming trajectory from the target forming point.

5. The laser deposition forming method as described in claim 4, characterized in that, After the step of fixing the laser cladding head, the method further includes: Obtain the advance movement length and calculate the advance angle corresponding to the advance movement length; The steps include controlling the rotary table to rotate by the advance angle, executing the laser activation, controlling the rotary table cooperating with the laser cladding head to rotate by a preset angle, and depositing and forming the target forming trajectory from the target forming point.

6. An electronic device, characterized in that, The electronic device includes: a memory, a processor, and a laser deposition modeling program stored in the memory and executable on the processor, the laser deposition modeling program being configured to implement the steps of the laser deposition modeling method as described in any one of claims 1 to 5.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a laser deposition modeling program, which, when executed by a processor, implements the steps of the laser deposition modeling method as described in any one of claims 1 to 5.

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