Method and apparatus for trajectory generation for additive manufacturing

Abstract

The application provides a kind of additive manufacturing trajectory generation method and device, its method includes: the model to be printed is layered, determines the filling line of each layer section of the model to be printed;According to the angle division result between the normal vector of the first and last end point of the filling line and the direction of the Z-axis of the robot coordinate system, the coordinates and directions of a plurality of path points on the filling line are determined;According to the coordinates and directions of the path points, the printing trajectory of the robot is determined.The printing trajectory of the start and end position of each layer to be printed of the model to be printed is optimized, the industrial robot motion trajectory is smoother through the interpolation of path points and posture optimization, and the printing speed is uniform and consistent.

Description

Technical Field

[0001] The present invention relates to the technical field of additive manufacturing, and in particular to a method and device for generating a trajectory for additive manufacturing. Background Art

[0002] Currently, printing devices with three or four degrees of freedom lack rotational freedom, so the mobile device carrying the laser head or print head cannot achieve support-free printing during the printing process. This limits the geometric shape of the printed object and the printing efficiency to a certain extent.

[0003] 3D printing using an industrial robot carrying a laser cladding head and feeding powder or wire is a commonly used additive manufacturing process. It has the characteristics of fast printing speed and large workpiece size.

[0004] However, the acceleration and deceleration of industrial robots will cause excessive deposition of materials in low-speed areas, resulting in printing defects. Summary of the Invention

[0005] The present invention provides a method and device for generating a trajectory for additive manufacturing, which is used to solve the defect in the prior art that the acceleration and deceleration movements of industrial robots will cause transitional deposition of materials in low-speed areas, and realize a trajectory generation method for additive manufacturing with a more uniform printing speed.

[0006] The present invention provides a method for generating a trajectory for additive manufacturing, comprising:

[0007] Layering the model to be printed, and determining a filling line for each cross section of the model to be printed;

[0008] Determining the coordinates and directions of multiple path points on the filling line according to the angle division result between the normal vectors of the starting and ending points of the filling line and the Z-axis direction of the robot coordinate system;

[0009] The printing trajectory of the robot is determined according to the coordinates and directions of the path points.

[0010] According to a method for generating a trajectory for additive manufacturing provided by the present invention, the step of dividing the model to be printed into layers and determining the filling line of each cross-section of the model to be printed specifically includes:

[0011] The model to be printed is cut along the Z-axis direction of the robot coordinate system, and the contour curve of each cross section obtained by cutting is determined;

[0012] Determining a minimum bounding box of the contour curve of each cross section, and generating a set of printing auxiliary lines about the minimum bounding box based on a predetermined offset distance;

[0013] Perform a Boolean operation on the intersection of the contour curve of each cross section and the printed auxiliary line to obtain the filling line of each cross section.

[0014] According to a method for generating a trajectory for additive manufacturing provided by the present invention, the step of determining the coordinates and directions of multiple path points on the filling line based on the angle division result between the normal vectors of the starting and ending points of the filling line and the Z-axis direction of the robot coordinate system specifically includes:

[0015] generating a filling path sequence of the filling lines of each cross section, and determining normal vectors of two endpoints of each filling path in the filling path sequence;

[0016] Determining a deviation angle between the normal vector and the Z-axis direction of the robot coordinate system, and dividing the deviation angle according to the deviation angle and the number of preset path points;

[0017] The coordinates and directions of the path points are determined according to the division results of the deviation angles.

[0018] According to a method for generating a trajectory for additive manufacturing provided by the present invention, the step of generating a filling path sequence for the filling line of each cross section specifically includes:

[0019] A fill path sequence is generated using a zigzag topology to generate fill lines for each layer of cross section.

[0020] According to a method for generating a trajectory for additive manufacturing provided by the present invention, the step of dividing the deviation angle according to the deviation angle and the preset number of path points specifically includes:

[0021] Determine a first positioning point in the filling path whose normal vector is perpendicular to the Z-axis direction of the robot coordinate system and is closest to the starting endpoint of the filling path, and a point closest to the ending endpoint of the filling path as a second positioning point;

[0022] Evenly dividing a first angle between a starting endpoint of the filling path and a normal vector of the first positioning point according to a preset number of path points, and evenly dividing a second angle between an ending endpoint of the filling path and a normal vector of the second positioning point according to a preset number of path points;

[0023] An intersection point between an angle bisector that equally divides the first angle and the second angle and the filling path is determined as a path point.

[0024] According to a method for generating a trajectory for additive manufacturing provided by the present invention, before the step of dividing the deviation angle according to the deviation angle and the preset number of path points, the method further includes:

[0025] Determine a first path length between a starting endpoint of the filling path and a first positioning point; determine a second path length between an ending endpoint of the filling path and a second positioning point;

[0026] Determining the first path length and the second path length as path lengths to be equally divided;

[0027] The integer result of the ratio of the length of the path to be evenly divided to the cladding speed of the robot is used as the preset number of path points.

[0028] The present invention also provides a trajectory generation device for additive manufacturing, comprising:

[0029] A line determination module is used to divide the model to be printed into layers and determine the filling line of each cross section of the model to be printed;

[0030] A path point determination module is used to determine the coordinates and directions of multiple path points on the filling line according to the angle division result between the normal vectors of the starting and ending points of the filling line and the Z-axis direction of the robot coordinate system;

[0031] The trajectory generation module is used to determine the printing trajectory of the robot according to the coordinates and directions of the path points.

[0032] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method for generating a trajectory for additive manufacturing as described above is implemented.

[0033] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements any of the above-described methods for generating a trajectory for additive manufacturing.

[0034] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the computer program implements any one of the above-described methods for generating a trajectory for additive manufacturing.

[0035] The trajectory generation method and device provided by the present invention optimize the printing trajectory of the start and end positions of each layer to be printed of the printed model, and make the motion trajectory of the industrial robot smoother and the printing speed more uniform through the interpolation of path points and posture optimization, thereby avoiding the phenomenon of local excessive deposition. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0037] Figure 1 This is one of the flow charts of the method for generating a trajectory for additive manufacturing provided by the present invention;

[0038] Figure 2 Schematic diagram of the minimum bounding box in the additive manufacturing trajectory generation method provided by the present invention;

[0039] Figure 3 It is a schematic diagram of printing auxiliary lines in the trajectory generation method for additive manufacturing provided by the present invention;

[0040] Figure 4 is a schematic diagram of a filling line in the trajectory generation method for additive manufacturing provided by the present invention;

[0041] Figure 5 is a schematic diagram of angle averaging in the additive manufacturing trajectory generation method provided by the present invention;

[0042] Figure 6 This is the second flow chart of the additive manufacturing trajectory generation method provided by the present invention;

[0043] Figure 7 It is a structural schematic diagram of the trajectory generating device for additive manufacturing provided by the present invention;

[0044] Figure 8 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0045] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0046] The following combination Figures 1 to 6 The trajectory generation method of additive manufacturing of the present invention is introduced, such as Figure 1 As shown, including:

[0047] Step 101, dividing the model to be printed into layers, and determining the filling lines of each cross section of the model to be printed;

[0048] Optionally, the model to be printed is layered in a fixed direction. The layering direction can be determined according to the shape of the model to be printed, and each cross section of the model to be printed after layering can be as convenient for printing as possible.

[0049] Optionally, the model to be printed may be evenly layered, or may be unevenly layered according to the shape of the model to be printed.

[0050] After layering, the shape of each cross section of the model to be printed is determined, and then the filling line of each cross section is determined according to the shape of each cross section, which serves as the basis for the filling path.

[0051] Step 102, determining the coordinates and directions of a plurality of path points on the filling line according to the angle division result between the normal vectors of the starting and ending points of the filling line and the Z-axis direction of the robot coordinate system;

[0052] It should be noted that in additive manufacturing, when the robot prints a flat surface, the laser print head moves directly along a straight path to print, so the printing speed is faster; when printing on inclined surfaces or curved surfaces that have an angle with the Z-axis direction of the robot coordinate system, it is necessary to adjust the orientation of the laser print head according to the normal of each path point to be printed during the printing process. When the adjustment range is large, the robot's printing speed is slower.

[0053] For example, if the model to be printed is a sphere, after the sphere is layered according to the radial direction of the sphere, the outermost part of each layer's cross section is an arc surface, and the middle position is a flat part that can be printed directly. Therefore, in the process of printing the outermost and middle parts, local deposition is likely to occur due to uneven printing speed.

[0054] To this end, during the printing process, it is necessary to distinguish the flat parts that can be printed directly from other parts that need to be rotated and adjusted by the laser print head, and optimize the rotation adjustment trajectory of the laser print head to make the overall printing speed more balanced, thereby reducing the occurrence of local excessive deposition.

[0055] In a fill line determined by a section to be printed of a model to be printed, the angle between the normal vector of the start and end points of the fill line and the Z-axis direction is determined in order to determine the area in the fill line where the trajectory of the laser print head needs to be optimized.

[0056] The angle between the normal vector of the starting and end points of the filling route and the Z-axis direction of the robot coordinate system is divided. That is, the angle that needs to be adjusted during the printing process of the laser print head is divided from a larger angle into multiple smaller angles, thereby facilitating the movement of the laser print head and improving the movement speed of the laser print head during printing of this area.

[0057] On this basis, it can be understood that the trajectory optimization of the laser print head is carried out from the direction of optimizing the rotation angle of the laser print head. The results of the angle adjustment still need to be converted into a printing trajectory, that is, the coordinates and directions of each path point on the filling line, in order to finally determine the printing trajectory of the laser print head.

[0058] Step 103: Determine the printing trajectory of the robot according to the coordinates and directions of the path points.

[0059] According to the coordinates and directions of the final determined path points, they are organized into the form of path point coordinates and normal vectors. In the robot coordinate system, that is, the working coordinate system of the laser print head, each path point and its normal vector are added to the robot controller in the form of three-dimensional coordinate position and q1, q2, q3, and q4 quaternion postures to generate the 3D printing trajectory of the laser print head, that is, the printing trajectory of the robot.

[0060] The present invention optimizes the printing trajectory of the start and end positions of each layer to be printed of the model to be printed, and makes the motion trajectory of the industrial robot smoother and the printing speed more uniform through the interpolation of path points and posture optimization, thereby avoiding the phenomenon of local excessive deposition.

[0061] In the additive manufacturing trajectory generation method of the present invention, the step of dividing the model to be printed into layers and determining the filling lines of each cross section of the model to be printed specifically includes:

[0062] The model to be printed is cut along the Z-axis direction of the robot coordinate system, and the contour curve of each cross section obtained by cutting is determined;

[0063] Optionally, the model to be printed is an STL (STereoLithography) model.

[0064] The model to be printed is divided into equal sections along the positive Z-axis of the robot coordinate system. This division method facilitates the robot's printing operation. In other feasible implementations, the model to be printed can be divided first, and then the division direction is adjusted to the Z-axis direction of the robot coordinate system. In other embodiments, the model to be printed can be rotated as a whole so that after the rotation, the division direction of the model to be printed is parallel to the Z-axis direction of the robot coordinate system.

[0065] Furthermore, after segmentation, the contour curve of the i-layer cross section of the model to be printed is obtained. On this basis, the corresponding filling density is pre-set according to the printing requirements. ρ and offset times γ .

[0066] Determining a minimum bounding box of the contour curve of each cross section, and generating a set of printing auxiliary lines about the minimum bounding box based on a predetermined offset distance;

[0067] like Figure 2 As shown, the minimum enclosing rectangle of the contour curve of each layer of cross section is used as the minimum enclosing box of the contour curve of each layer of cross section, and its length and width are represented by L and H respectively.

[0068] The offset distance D is predetermined as follows: D = L / γ .

[0069] On this basis, a set of printing auxiliary lines about the minimum bounding box is generated from top to bottom with an offset distance D, such as Figure 3 shown.

[0070] Perform a Boolean operation on the intersection of the contour curve of each cross section and the printed auxiliary line to obtain the filling line of each cross section.

[0071] Perform a Boolean operation on the intersection of the contour curve of the i-th layer section and the printed auxiliary line to obtain a set of filling lines within the section contour curve, such as Figure 4 shown.

[0072] It can be understood that the filling line of each cross section is a group of line segments.

[0073] Name the filling line of the i-th layer section as the array line[ γ ],in, γ is a natural number, .

[0074] In the additive manufacturing trajectory generation method of the present invention, the step of determining the coordinates and directions of multiple path points on the filling line based on the angle division result between the normal vectors of the starting and ending points of the filling line and the Z-axis direction of the robot coordinate system specifically includes:

[0075] generating a filling path sequence of the filling lines of each cross section, and determining normal vectors of two endpoints of each filling path in the filling path sequence;

[0076] Generate corresponding filling paths according to the filling lines of each cross section, and combine them to obtain a filling path sequence.

[0077] Fill paths are filled lines with directions. Figure 4 Taking the fill lines shown as an example, in one feasible embodiment, the generated fill path is that the fill lines of each row are printed in a fixed direction from left to right; in another feasible embodiment, the first row from top to bottom is used as the first printing row, and printing is completed from left to right, and the second row from top to bottom is used as the second printing row, and printing is completed from right to left, so that the printing track is continuous.

[0078] Array line[ γ]Generate a fill path sequence and determine the normal vectors of the start and end endpoints of each fill path in the fill path sequence, such as Figure 5 The blue directed arrows corresponding to the starting point and end point of the fill path are shown in the figure.

[0079] Determine a deviation angle between the normal vector and the Z-axis direction of the robot coordinate system, and divide the deviation angle according to the deviation angle and the number of preset path points;

[0080] The deviation angle between the normal vector corresponding to the starting endpoint of each filling path and the Z-axis direction of the robot coordinate system is as follows: Figure 5 As shown, the blue directed arrow corresponding to the starting point of the filling path rotates to AngZ[i] The corresponding blue directed arrows have the desired angle.

[0081] The processing of the end endpoint of each fill path is the same as that of the start endpoint, so it will not be repeated here.

[0082] In this way, the starting area and the ending area that need to be optimized are determined.

[0083] On this basis, the number of path points is predetermined, and the deviation angle is divided according to the number of path points. The number of path points is equal to the number of angle bisectors generated by dividing the deviation angle. For example, if there are 4 path points and the deviation angle is 10°, the deviation angle is evenly divided into 5 parts, each with a deflection angle of 2°.

[0084] Optionally, the number of preset path points is predetermined based on experience.

[0085] The coordinates and directions of the path points are determined according to the division results of the deviation angles.

[0086] Based on the angle division, the intersection of the angle bisector obtained by division and the filling path is determined as the path point, such as Figure 5 As shown, Figure 5 The orange directed arrow in the figure is the angle bisector obtained by division. The intersection of the angle bisector and the fill path is used as the path point obtained by division. Based on the original fill path starting point and fill path end point, it is used as the additional path point.

[0087] The coordinates and orientation of each path point are determined and used to convert it into a trajectory for the laser print head.

[0088] In the additive manufacturing trajectory generation method of the present invention, the step of generating a filling path sequence of the filling lines of each cross section specifically includes:

[0089] A fill path sequence is generated using a zigzag topology to generate fill lines for each layer of cross section.

[0090] In this embodiment, a zigzag topology structure is used to generate a filling path sequence.

[0091] Specifically, the two endpoints of the odd-numbered row filling path are recorded as VStart[i] and VEnd[i], and the filling path sequence is generated in the order of i∈[1, 2, 3…γ].

[0092] The two endpoints of the even-numbered fill path are VStart[i-1], VEnd[i-1], and the fill path sequence is generated in the order of i∈[γ…3, 2, 1].

[0093] In the additive manufacturing trajectory generation method of the present invention, the step of dividing the deviation angle according to the deviation angle and the preset number of path points specifically includes:

[0094] Determine a first positioning point in the filling path whose normal vector is perpendicular to the Z-axis direction of the robot coordinate system and is closest to the starting endpoint of the filling path, and a point closest to the ending endpoint of the filling path as a second positioning point;

[0095] like Figure 5 As shown, for each filling path, in its starting area, determine the first positioning point in the filling path whose normal vector is perpendicular to the Z-axis direction of the robot coordinate system and is closest to the starting endpoint of the filling path. The point closest to the ending endpoint of the filling path is the second positioning point, that is, the intersection of the second blue directed arrow from left to right and the filling path is the first positioning point, and the intersection of the third blue directed arrow and the filling path is the second positioning point.

[0096] Through the above method, the adjustment area of ​​the robot printing is divided. It can be understood that the area between the starting point of the filling path to the first positioning point, and the area between the second positioning point and the end point of the filling path is where the printing angle will change, so the robot's printing path needs to be adjusted and optimized. The area between the first positioning point and the second positioning point is the area where the robot can complete printing by moving directly in the XOY plane.

[0097] Evenly dividing a first angle between a starting endpoint of the filling path and a normal vector of the first positioning point according to a preset number of path points, and evenly dividing a second angle between an ending endpoint of the filling path and a normal vector of the second positioning point according to a preset number of path points;

[0098] An intersection point between an angle bisector that equally divides the first angle and the second angle and the filling path is determined as a path point.

[0099] Continue to refer to Figure 5The first angle is the angle between the first two blue directed arrows from left to right, and the second angle is the angle between the last two blue directed arrows from left to right.

[0100] The first angle is evenly divided using the following angle division formula:

[0101] ;

[0102] Where, Indicates the Z-axis direction of the robot coordinate system, is the normal vector corresponding to the starting endpoint of the filled path, t is the preset number of path points, and mod() is the remainder function.

[0103] The second angle is evenly divided using the following angle division formula:

[0104] ;

[0105] Where, Indicates the normal vector corresponding to the end point of the fill path.

[0106] After the first and second angles are divided, each angle bisector obtained by the division can be Figure 5 The intersection of the orange directed arrows in and the filled path determines the path points.

[0107] In the trajectory generation method for additive manufacturing of the present invention, before the step of dividing the deviation angle according to the deviation angle and the preset number of path points, the method further includes:

[0108] Determine a first path length between a starting endpoint of the filling path and a first positioning point; determine a second path length between an ending endpoint of the filling path and a second positioning point;

[0109] Determining the first path length and the second path length as path lengths to be equally divided;

[0110] The integer result of the ratio of the length of the path to be evenly divided to the cladding speed of the robot is used as the preset number of path points.

[0111] In order to more accurately determine the number of path points, such as Figure 5 As shown, first determine the lengths L of the paths to be evenly divided corresponding to the starting and ending parts of the filling path.

[0112] Specifically, in each filling path, the portion between its starting endpoint and the first positioning point is determined as the first path, and the length of the first path is determined as the first path length. The second path length is determined in the same manner.

[0113] On this basis, the number of path points t is calculated as follows:

[0114] ;

[0115] Where V is the cladding speed of the robot.

[0116] Among them, V is generally 5-20mm / s.

[0117] Since the path points are integers, the calculated result is rounded up and used as the number of preset path points.

[0118] Optionally, different rounding methods such as rounding up or rounding down or setting a threshold may be used for rounding.

[0119] In this embodiment, in order to facilitate the continuity of the robot's movement, a rounding-up method is adopted to determine as many path points as possible.

[0120] On this basis, a complete trajectory generation process is as follows Figure 6 shown.

[0121] The present invention divides the slice contour into equal intervals through the minimum bounding box, and then performs Boolean operations on the slice contour and the printing auxiliary line to generate a filling path. At the same time, it also innovatively optimizes the normal vectors of the two end points according to the angle averaging principle, making it easier to achieve support-free printing in the 3D printing process, thereby further broadening the practicality of the robotic arm printing system.

[0122] The trajectory generation device for additive manufacturing provided by the present invention is described below. The trajectory generation device for additive manufacturing described below and the trajectory generation method for additive manufacturing described above can refer to each other.

[0123] like Figure 7 As shown, the trajectory generation device for additive manufacturing includes a line determination module 701, a path point determination module 702 and a trajectory generation module 703:

[0124] A line determination module 701 is used to divide the model to be printed into layers and determine the filling lines of each cross section of the model to be printed;

[0125] Optionally, the model to be printed is layered in a fixed direction. The layering direction can be determined according to the shape of the model to be printed, and each cross section of the model to be printed after layering can be as convenient for printing as possible.

[0126] Optionally, the model to be printed may be evenly layered, or may be unevenly layered according to the shape of the model to be printed.

[0127] After layering, the shape of each cross section of the model to be printed is determined, and then the filling line of each cross section is determined according to the shape of each cross section, which serves as the basis for the filling path.

[0128] A path point determination module 702 is configured to determine the coordinates and directions of a plurality of path points on the filling line according to the angle division result between the normal vectors of the start and end points of the filling line and the Z-axis direction of the robot coordinate system;

[0129] It should be noted that in additive manufacturing, when the robot prints a flat surface, the laser print head moves directly along a straight path to print, so the printing speed is faster; when printing on inclined surfaces or curved surfaces that have an angle with the Z-axis direction of the robot coordinate system, it is necessary to adjust the orientation of the laser print head according to the normal of each path point to be printed during the printing process. When the adjustment range is large, the robot's printing speed is slower.

[0130] For example, if the model to be printed is a sphere, after the sphere is layered according to the radial direction of the sphere, the outermost part of each layer's cross section is an arc surface, and the middle position is a flat part that can be printed directly. Therefore, in the process of printing the outermost and middle parts, local deposition is likely to occur due to uneven printing speed.

[0131] To this end, during the printing process, it is necessary to distinguish the flat parts that can be printed directly from other parts that need to be rotated and adjusted by the laser print head, and optimize the rotation adjustment trajectory of the laser print head to make the overall printing speed more balanced, thereby reducing the occurrence of local excessive deposition.

[0132] In a fill line determined by a section to be printed of a model to be printed, the angle between the normal vector of the start and end points of the fill line and the Z-axis direction is determined in order to determine the area in the fill line where the trajectory of the laser print head needs to be optimized.

[0133] The angle between the normal vector of the starting and end points of the filling route and the Z-axis direction of the robot coordinate system is divided. That is, the angle that needs to be adjusted during the printing process of the laser print head is divided from a larger angle into multiple smaller angles, thereby facilitating the movement of the laser print head and improving the movement speed of the laser print head during printing of this area.

[0134] On this basis, it can be understood that the trajectory optimization of the laser print head is carried out from the direction of optimizing the rotation angle of the laser print head. The results of the angle adjustment still need to be converted into a printing trajectory, that is, the coordinates and directions of each path point on the filling line, in order to finally determine the printing trajectory of the laser print head.

[0135] The trajectory generation module 703 is used to determine the printing trajectory of the robot according to the coordinates and directions of the path points.

[0136] According to the coordinates and directions of the final determined path points, they are organized into the form of path point coordinates and normal vectors. In the robot coordinate system, that is, the working coordinate system of the laser print head, each path point and its normal vector are added to the robot controller in the form of three-dimensional coordinate position and q1, q2, q3, and q4 quaternion postures to generate the 3D printing trajectory of the laser print head, that is, the printing trajectory of the robot.

[0137] The present invention optimizes the printing trajectory of the start and end positions of each layer to be printed of the model to be printed, and makes the motion trajectory of the industrial robot smoother and the printing speed more uniform through the interpolation of path points and posture optimization, thereby avoiding the phenomenon of local excessive deposition.

[0138] Figure 8 An example of a physical structure diagram of an electronic device is shown below. Figure 8 As shown, the electronic device may include: a processor 810, a communications interface 820, a memory 830, and a communications bus 840, wherein the processor 810, the communications interface 820, and the memory 830 communicate with each other via the communications bus 840. The processor 810 may call logic instructions in the memory 830 to execute a trajectory generation method for additive manufacturing, the method comprising: dividing a model to be printed into layers, determining a fill line for each cross-section of the model to be printed; determining the coordinates and directions of a plurality of path points on the fill line based on the angle division result between the normal vectors of the start and end points of the fill line and the Z-axis direction of the robot coordinate system; and determining the printing trajectory of the robot based on the coordinates and directions of the path points.

[0139] Furthermore, the logic instructions in the aforementioned memory 830 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product, stored in a storage medium, includes instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, mobile hard drives, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical disks.

[0140] On the other hand, the present invention also provides a computer program product, which includes a computer program, which can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the additive manufacturing trajectory generation method provided by the above methods, which includes: layering the model to be printed, and determining the filling line of each cross-section of the model to be printed; determining the coordinates and directions of multiple path points on the filling line based on the angle division result between the normal vector of the start and end points of the filling line and the Z-axis direction of the robot coordinate system; and determining the printing trajectory of the robot based on the coordinates and direction of the path points.

[0141] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the trajectory generation method for additive manufacturing provided by the above-mentioned methods, the method comprising: dividing the model to be printed into layers, and determining the filling line of each cross-section of the model to be printed; determining the coordinates and directions of multiple path points on the filling line based on the angle division result between the normal vector of the start and end points of the filling line and the Z-axis direction of the robot coordinate system; and determining the printing trajectory of the robot based on the coordinates and directions of the path points.

[0142] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0143] Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented using software plus a necessary general-purpose hardware platform, or of course, hardware. Based on this understanding, the essence of the above technical solution, or the portion that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, or an optical disk, and includes a number of instructions for causing a computer device (such as a personal computer, server, or network device) to execute the methods described in each embodiment or certain portions of the embodiments.

[0144] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for generating a trajectory for additive manufacturing, characterized in that: include: Layering the model to be printed, and determining a filling line for each cross section of the model to be printed; Determining the coordinates and directions of multiple path points on the filling line according to the angle division result between the normal vectors of the starting and ending points of the filling line and the Z-axis direction of the robot coordinate system; Determine the printing trajectory of the robot according to the coordinates and directions of the path points; The step of dividing the model to be printed into layers and determining the filling lines of each cross section of the model to be printed specifically includes: The model to be printed is cut along the Z-axis direction of the robot coordinate system, and the contour curve of each cross section obtained by cutting is determined; Determining a minimum bounding box of the contour curve of each cross section, and generating a set of printing auxiliary lines about the minimum bounding box based on a predetermined offset distance; Perform a Boolean operation on the intersection of the contour curve of each cross section and the printed auxiliary line to obtain the filling line of each cross section.

2. The method for generating a trajectory for additive manufacturing according to claim 1, wherein: The step of determining the coordinates and directions of multiple path points on the filling line according to the angle division result between the normal vectors of the starting and ending points of the filling line and the Z-axis direction of the robot coordinate system specifically includes: generating a filling path sequence of the filling lines of each cross section, and determining normal vectors of two endpoints of each filling path in the filling path sequence; Determining a deviation angle between the normal vector and the Z-axis direction of the robot coordinate system, and dividing the deviation angle according to the deviation angle and the number of preset path points; The coordinates and directions of the path points are determined according to the division results of the deviation angles.

3. The method for generating a trajectory for additive manufacturing according to claim 2, wherein: The step of generating a filling path sequence of the filling lines of each cross section specifically includes: A fill path sequence is generated using a zigzag topology to generate fill lines for each layer of cross section.

4. The method for generating a trajectory for additive manufacturing according to claim 2, wherein: The step of dividing the deviation angle according to the deviation angle and the preset number of path points specifically includes: Determine a first positioning point in the filling path whose normal vector is perpendicular to the Z-axis direction of the robot coordinate system and is closest to the starting endpoint of the filling path, and a point closest to the ending endpoint of the filling path as a second positioning point; Evenly dividing a first angle between a starting endpoint of the filling path and a normal vector of the first positioning point according to a preset number of path points, and evenly dividing a second angle between an ending endpoint of the filling path and a normal vector of the second positioning point according to a preset number of path points; An intersection point between an angle bisector that equally divides the first angle and the second angle and the filling path is determined as a path point.

5. The method for generating a trajectory for additive manufacturing according to claim 4, wherein: Before the step of dividing the deviation angle according to the deviation angle and the preset number of path points, the method further includes: Determine a first path length between a starting endpoint of the filling path and a first positioning point; determine a second path length between an ending endpoint of the filling path and a second positioning point; Determining the first path length and the second path length as path lengths to be equally divided; The integer result of the ratio of the length of the path to be evenly divided to the cladding speed of the robot is used as the preset number of path points.

6. A trajectory generation device for additive manufacturing, characterized in that: include: A line determination module is used to divide the model to be printed into layers and determine the filling line of each cross section of the model to be printed; A path point determination module is used to determine the coordinates and directions of multiple path points on the filling line according to the angle division result between the normal vectors of the starting and ending points of the filling line and the Z-axis direction of the robot coordinate system; A trajectory generation module, configured to determine a printing trajectory of the robot based on the coordinates and directions of the path points; The line determination module is specifically used to cut the to-be-printed model along the Z-axis direction of the robot coordinate system, and determine the contour curve of each cross section obtained by cutting; Determining a minimum bounding box of the contour curve of each cross section, and generating a set of printing auxiliary lines about the minimum bounding box based on a predetermined offset distance; Perform a Boolean operation on the intersection of the contour curve of each cross section and the printed auxiliary line to obtain the filling line of each cross section.

7. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the additive manufacturing trajectory generation method according to any one of claims 1 to 5 is implemented.

8. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for generating a trajectory for additive manufacturing according to any one of claims 1 to 5 is implemented.

9. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the method for generating a trajectory for additive manufacturing according to any one of claims 1 to 5 is implemented.

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