3D irregular object packaging method and system for subtractive manufacturing

Abstract

The invention discloses a 3D irregular object packaging method and system for subtractive manufacturing, and relates to the technical field of subtractive manufacturing. The method comprises the following steps: acquiring a container raw material and a to-be-packaged 3D object; calculating a collision-free space according to the container and the 3D object, and preliminarily generating a collision-free area; the collision-free areas are further screened according to the operation distance of the cutting tool, and candidate placement positions are formed; sorting the candidate positions according to the Euclidean distance to form a packaging layout; forming a cutting shell according to the accessible areas of all the 3D objects, and planning a cutting path according to the cutting shell; and cutting the 3D object according to the packaging layout, the cutting shell and the cutting path. According to the method, the limitation of a traditional packaging algorithm in subtractive manufacturing is solved, and a new solution is provided for the efficient and accurate manufacturing process.

Description

Technical Field

[0001] The present invention relates to the technical field of subtractive manufacturing, and in particular to a 3D irregular object packaging method and system for subtractive manufacturing. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] In the field of subtractive manufacturing, especially in computer numerical control (CNC) machining, how to efficiently and accurately cut multiple workpieces from raw materials is a key challenge. The traditional subtractive manufacturing process usually includes two stages: roughing and finishing. The roughing stage is mainly used to quickly remove excess material, while the finishing stage focuses on improving the surface quality and geometric accuracy of the workpiece. However, before roughing and finishing, the pre-processing stage of the raw material (i.e. cutting multiple workpieces from a large piece of raw material) plays a vital role in the final manufacturing efficiency and material utilization.

[0004] In the pre-processing stage of raw materials, the current material cutting problem can be analyzed and optimized by the model of Cutting Stock Problem (CSP). The core goal of the CSP problem is to minimize material waste and maximize the utilization of raw materials. This problem has been widely used in many industries, such as papermaking, steel, glass and wood processing. However, although one-dimensional and two-dimensional CSP problems have been widely studied, the CSP problem of three-dimensional irregular objects remains a complex and underexplored area, especially when considering tool collisions and interference between objects.

[0005] Although existing 3D object packing algorithms have made some progress in terms of space utilization, avoiding object overlap and object disassembly, these algorithms usually do not fully consider the process constraints of subtractive manufacturing, especially how to ensure that objects can be disassembled smoothly during the cutting process and how to avoid collisions between cutting tools and objects. Therefore, existing algorithms often cannot meet both high space utilization and process constraints, resulting in problems such as material waste or tool damage during the production process.

[0006] In addition, most current 3D packing methods only focus on the geometric shape of objects, while ignoring the accessibility of cutting tools and the actual processing limitations of raw materials. Many methods avoid interference between objects by creating simple bounding boxes (such as axis-aligned bounding boxes AABB), but these methods have limited effectiveness when dealing with irregularly shaped objects and cannot guarantee the cuttability of these objects in actual processing (i.e., whether they can be processed smoothly using cutting tools).

[0007] In summary, how to ensure high space utilization of three-dimensional irregular objects during the cutting process while allowing all objects to be smoothly disassembled has become a technical problem that needs to be urgently solved in the prior art. Summary of the invention

[0008] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a 3D irregular object packing method and system for subtractive manufacturing, which combines the three-dimensional packing of irregular objects with the cutting process constraints in subtractive manufacturing, aiming to optimize space utilization while ensuring that all objects can be smoothly cut and disassembled during the subtractive manufacturing process. This method not only solves the limitations of traditional packing algorithms in subtractive manufacturing, but also provides a new solution for efficient and precise manufacturing processes.

[0009] In order to achieve the above object, the present invention is implemented through the following technical solutions:

[0010] A first aspect of the present invention provides a 3D irregular object packaging method for subtractive manufacturing, comprising the following steps:

[0011] Obtain container raw materials and 3D objects to be packaged, and determine the order in which the 3D objects are placed;

[0012] Calculate the collision-free space based on the container and 3D objects, and preliminarily generate the collision-free area;

[0013] The collision-free area is further screened according to the operating distance of the cutting tool to form candidate placement positions;

[0014] Sort candidate locations according to Euclidean distance, place 3D objects one by one according to the sorting results, and adjust the placed 3D objects according to the disassembly order during the placement process to form a packaged layout;

[0015] Determine the accessible area around the placed 3D objects, form a cutting shell according to the accessible areas of all 3D objects, and plan a cutting path according to the cutting shell;

[0016] Cut 3D objects according to packing layout, cutting shell and cutting path.

[0017] Furthermore, the specific steps for calculating the collision-free space based on the container and the 3D object are:

[0018] voxelize the container and the 3D object to obtain the voxel grid of the new object and the voxel grid of the placed object;

[0019] The collision relationship between new objects and already placed objects in the voxel grid is calculated through a convolution method to initially generate collision-free areas.

[0020] Furthermore, the specific steps of further screening the collision-free area according to the operating distance of the cutting tool are as follows:

[0021] The distance field is calculated by calculating the distance of each voxel point to the nearest placed object;

[0022] The distance field results are further filtered according to the operating distance of the cutting tool to obtain candidate placement locations.

[0023] Furthermore, the specific steps of adjusting the placed 3D objects according to the disassembly order during the placement process are:

[0024] Place objects while verifying removability using removability constraints;

[0025] When there are interference issues, a tree search structure is used to adjust the placed 3D objects.

[0026] Furthermore, the accessible area is a voxel position that is accessible to the cutting tool without obstacles, and is used to ensure that the cutting tool does not collide with surrounding objects during the cutting process.

[0027] Furthermore, a compact or loose cutting shell is formed according to the accessible areas of all 3D objects.

[0028] Furthermore, the specific steps of planning the cutting path according to the cutting shell are as follows:

[0029] The cutting shell is cut along each cutting tool direction, and a cutting contour perpendicular to the cutting tool direction is generated as an actual cutting path.

[0030] A second aspect of the present invention provides a 3D irregular object packaging system for subtractive manufacturing, comprising:

[0031] The collision area generation module is configured to obtain container raw materials and 3D objects to be packaged, and determine the placement order of the 3D objects; calculate the collision-free space according to the container and the 3D objects, and preliminarily generate the collision-free area; further screen the collision-free area according to the operating distance of the cutting tool to form candidate placement positions;

[0032] A packing layout generation module is configured to sort candidate positions according to Euclidean distance, place 3D objects one by one according to the sorting results, and adjust the placed 3D objects according to the disassembly order during the placement process to form a packing layout;

[0033] a path planning module configured to determine accessible areas around the placed 3D objects, form a cutting shell based on the accessible areas of all 3D objects, and plan a cutting path based on the cutting shell;

[0034] The cutting module is configured to cut the 3D object according to the packaging layout, the cutting shell and the cutting path.

[0035] A third aspect of the present invention provides a medium having a program stored thereon, which, when executed by a processor, implements the steps in the 3D irregular object packaging method for subtractive manufacturing as described in the first aspect of the present invention.

[0036] The fourth aspect of the present invention provides a device, including a memory, a processor, and a program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps in the 3D irregular object packaging method for subtractive manufacturing as described in the first aspect of the present invention are implemented.

[0037] One or more of the above technical solutions have the following beneficial effects:

[0038] The present invention discloses a 3D irregular object packaging method and system for subtractive manufacturing, which can maximize the utilization of materials and reduce waste in a limited space by optimizing the placement order of objects and the generation of cutting shells. It is particularly suitable for manufacturing scenarios with expensive or scarce materials, significantly reducing material costs.

[0039] The algorithm of the invention dynamically considers the accessibility of the tool and the detachability of the object during the packaging process, ensuring that each object can be separated smoothly during the cutting process, avoiding the interlocking or collision problems common in traditional packaging. At the same time, by generating a compact or loose cutting shell and combining the tool direction to generate an optimized cutting path, the processing efficiency is significantly improved and the tool's idle travel and wear are reduced.

[0040] The algorithm of the present invention is not only applicable to objects of regular shapes, but also can process complex free-form surfaces and CAD models, and is applicable to a variety of manufacturing fields, such as graphite bearing manufacturing, jade carving, foam product manufacturing, etc. Through voxelization and convolution methods, efficient collision detection and path planning are achieved, which can automatically handle the packaging problem of large-scale objects, has good scalability, and is suitable for industrial-level applications.

[0041] Advantages of additional aspects of the present invention will be given in part in the following description, and in part will become obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0043] Figure 1 This is a schematic flow chart of a 3D irregular object packaging method for subtractive manufacturing according to a first embodiment of the present invention;

[0044] Figure 2 This is a schematic diagram of calculating a collision-free space using convolution in Embodiment 1 of the present invention;

[0045] Figure 3 A schematic diagram of a location where a model can be placed is shown in the first embodiment of the present invention;

[0046] Figure 4 This is a schematic diagram of dynamically adjusting the disassembly sequence through tree search in Embodiment 1 of the present invention;

[0047] Figure 5 A schematic diagram of generating a cuttable shell according to the first embodiment of the present invention;

[0048] Figure 6 This is a schematic diagram of cutting along a cuttable shell according to the first embodiment of the present invention;

[0049] Figure 7 This is a diagram showing the calculation results of a part of the program in the embodiment of the present invention. DETAILED DESCRIPTION

[0050] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0051] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "include" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or their combinations;

[0052] Embodiment 1:

[0053] Existing packing algorithms usually only focus on the space utilization between objects and avoiding object overlap, but fail to effectively consider the accessibility of cutting tools and the disassembly of objects. Therefore, the present invention aims to propose a new algorithm that can maximize space utilization and ensure that each object does not collide during the processing process and can be disassembled smoothly. The objectives of this method include: (1) Efficiently packing irregular shaped objects in three-dimensional space to maximize space utilization. (2) Ensure that the packaged objects can be cut smoothly during the subtractive manufacturing process, that is, avoid collisions between cutting tools and objects, and ensure that each object can be disassembled smoothly. (3) Combining the geometric shape of irregular objects and the accessibility of cutting tools, a new geometric shell structure is proposed to guide the planning of cutting paths and the disassembly order of objects.

[0054] Based on the above objectives, embodiment 1 of the present invention provides a 3D irregular object packaging method for subtractive manufacturing. The method introduces a cutting shell to ensure that the 3D irregular objects can be smoothly cut and separated after packaging, while maximizing space utilization and improving processing efficiency. The method is suitable for a variety of industrial manufacturing scenarios.

[0055] like Figure 1 As shown, Figure 1 (a) First, the input 3D object is voxelized to discretize it into a computable grid structure; Figure 1 (b) Then, the objects are packed in order from largest to smallest using a greedy algorithm; Figure 1 (c) For each packed 3D object, a cuttable shell is generated according to the current layout; Figure 1 (d) For the placement of a single new object: first generate a collision-free space, then find the best placement position by calculating the distance field of the space, and in the process ensure that the cuttable and collision-free requirements are met.

[0056] The specific steps include:

[0057] Step 1: Obtain container raw materials and 3D objects to be packaged, and determine the placement order of the 3D objects.

[0058] In a specific embodiment, a container raw material A with a fixed boundary and a 3D object S to be packaged are provided. 1 ,S 2 ,…,S m}, and determine their placement order. In the subsequent convolution calculation of collision-free areas and other processing steps, the model cannot collide with the boundary as a constraint.

[0059] Specifically, the placement order is determined based on the volume of the 3D objects from large to small. The 3D objects to be packed are sorted from large to small by volume to maximize space utilization. Placing larger objects first ensures that they occupy the appropriate position, while small objects are more likely to fill the remaining gaps, avoiding wasted space and reducing the complexity and calculation of subsequent placement.

[0060] In this embodiment, the container raw material refers to a solid raw material (such as a metal block) used for processing in reality, which is a fixed boundary area within which 3D objects are arranged and processed. The role of the container is to provide a fixed boundary to limit and manage the placement and cutting process of 3D objects.

[0061] Step 2: Calculate the collision-free space based on the container and the 3D object, and preliminarily generate the collision-free area.

[0062] Step 2.1: voxelize the container and the 3D object to obtain the voxel grid of the new object and the voxel grid of the placed object.

[0063] In a specific embodiment, Figure 1 As shown in (1) in the figure, the container and each 3D object are voxelized. The continuous geometric shapes are converted into discrete voxel forms, making it easier to perform collision detection and spatial calculations on these geometric shapes. Specifically, the 3D object S i For example, each 3D object S i will be represented as a voxel grid Here x is a voxel point in the grid:

[0064]

[0065] Similarly, the voxel representation of the placed object set O is I O (x), defined as:

[0066]

[0067] In this embodiment, 3D objects are packed and placed into the container in sequence, one 3D object is placed at a time, the placed objects are objects that have been placed, and the unplaced objects are objects to be placed this time.

[0068] The same voxelization process as above is performed on the container.

[0069] Step 2.2: Calculate the collision relationship between the new object and the placed objects in the voxel grid through the convolution method to initially generate collision-free areas.

[0070] like Figure 2 As shown, a convolution operation is used to calculate the collision-free space. Figure 2 The process of generating a collision-free space based on convolution is shown. First, the input object is voxelized in the upper left and lower left corners of the figure, and the collision voxels are assigned values ​​of -1 and the non-collision voxels are assigned values ​​of 0 through convolution. The upper part of the figure shows the generation of a preliminary collision-free placement space in the white area. Subsequently, the constraints of the distance field and tool width are added to further refine the collision-free placement space. The right side of the figure shows the final generation of the tool collision-free white area placement space. This process ensures that objects can avoid collisions with other objects and tools when placed.

[0071] In a specific implementation, the core idea of ​​convolution is to superimpose the voxel grid of the new object with the voxel grid of the already placed object. If the voxel overlaps at a certain position, it is considered that there is a collision at that position. Indicates whether there is a collision at grid point x, defined as follows:

[0072]

[0073] when , it means that the location is collision-free and may be used as a placement area for new objects.

[0074] Step 3: Further screen the collision-free area according to the operating distance of the cutting tool to form a candidate placement position. Specifically, detect the collision between the new object and the placed object, combine the distance field to ensure that the tool is reachable, and form the final feasible collision-free position as the candidate placement position.

[0075] Step 3.1: Calculate the distance field by calculating the distance of each voxel point to the nearest placed object.

[0076] In a specific embodiment, after the collision-free space is determined, a further constraint is to ensure that the cutting tool can reach each placement location. In order to evaluate the reachability of the tool, Figure 2 As shown in Figure 1, the algorithm introduces a distance field to calculate the distance between each voxel point and the nearest placed object. Defined as:

[0077]

[0078] Among them, |xp j | represents the distance from voxel point x to the nearest placed object p j distance.

[0079] Step 3.2: The distance field results are further screened according to the operating distance of the cutting tool to obtain candidate placement positions.

[0080] In a specific implementation, the distance field result is further screened to define a final feasible collision-free position:

[0081]

[0082] Where w is the width of the cutting tool. If the distance field value of a voxel point x is greater than w, then the position is considered a feasible candidate placement position, otherwise it will be excluded.

[0083] Step 4: Sort candidate locations according to Euclidean distance, place 3D objects one by one according to the sorting results, and adjust the placed 3D objects according to the disassembly order during the placement process to form a packed layout.

[0084] Step 4.1: Place the objects while verifying the removability using the removability constraints.

[0085] Step 4.1.1: Figure 3 As shown, the Euclidean distance of each candidate position is calculated. Figure 3 Shows how the algorithm determines where to place the model. Figure 3 The generated white area in (a) has no collision space; Figure 3 (b) Calculate the Euclidean distance field from each voxel to the lower left corner of the container; Figure 3 (c) combines distance information with collision-free space to sort candidate locations; Figure 3 The red box in (d) selects a non-negative voxel position as the new object placement position; Figure 3 (e) The layout after placing the red triangle object at the selected position; Figure 3 (f) generating a tool collision field corresponding to the placement layout; Figure 3 (g) and Figure 3 (h) Analysis of the collision field through the connected branches of the model; Figure 3 (i), (j), and (k) in (c) adjust the disassembly sequence to remove the front obstacle; finally, Figure 3 In (l), the red object satisfies the cuttable constraint.

[0086] For each voxel position p in the candidate placement i , calculate its voxel p at the lower left corner of the container 0 The Euclidean distance of:

[0087]

[0088] Where x represents a voxel point in three-dimensional space, |xp 0 | means from x to p 0 The Euclidean distance of .

[0089] Step 4.1.2: Sort all non-negative voxel positions by Euclidean distance from small to large to obtain an ordered list of candidate positions. Try to move object S one by one in the sorted order. i Place it at each candidate position to generate the current packaging layout

[0090]

[0091] in, and I o (x) are the objects S j and a voxelized representation of the placed object O.

[0092] Step: 4.1.3: For each tool direction C i , calculate its voxel representation And calculate the collision field by convolution method Global tool collision field Γ C Yes all The intersection of:

[0093]

[0094] Check Γ C Does it exist in and I O If and I O If they are not in the same connected component, the packing layout G satisfies the tool no-collision constraint.

[0095] The collision field of a tool is a three-dimensional area that is used to detect and indicate whether an object collides with the tool during the cutting process. By calculating the reachability of the object and the tool in multiple directions, the collision field identifies which voxels can be safely contacted and processed by the tool. The calculation of the collision field ensures that the tool will not collide with newly placed objects or other already placed objects during operation, thereby satisfying the collision-free constraint during the cutting process.

[0096] Step 4.1.4: If you package the layout To meet the tool collision constraint, the tool is moved along each tool direction. O Perform a sweep operation to attempt disassembly along each tool direction If there is at least one direction in which the disassembly is unobstructed Then pack layout The no interlocking constraint is satisfied.

[0097] Step 4.1.5: If the current packaging layout If all the disassembly constraints are met, that is, the no interlocking constraint and the tool no collision constraint are met at the same time, the 3D object S i Add to the front of the disassembly sequence. If S i If the disassembly constraint is not satisfied, then try to remove the front 3D object to make it disassemblyable through step 4.2 until a feasible disassembly sequence is found.

[0098] Step 4.2: When there is an interference problem, the placed 3D objects are adjusted using a tree search structure to ensure that all 3D objects can be separated smoothly.

[0099] In a specific implementation, when the current 3D object S i In layout When the disassembly constraint is not met, the algorithm adjusts the disassembly order to ensure that all 3D objects can be separated smoothly, such as Figure 4 shown.

[0100] Figure 4 (a) shows the newly placed Figure 3The red triangle object in the middle attempts to be the first disassembly object in the layout. The disassembly sequence is marked by numbers, but the sequence marked in red font is invalid because the red object cannot be cut and disassembled; Figure 4 (b), (d), and (f) in the figure propose three alternative strategies, which ensure machinability by preferentially disassembling other objects in the light green dashed area; Figure 4 (c), (e), and (g) correspond to the adjusted feasible disassembly sequences respectively.

[0101] Specifically, first, try to remove one or more of the disassembly sequences located at S i 3D object in front or And re-verify S i If S i If it still cannot be disassembled, continue to remove more 3D objects in front. In order to systematically explore all possible disassembly sequences, the algorithm adopts a tree search structure and regards each possible disassembly sequence as a node of the tree. Start recursively generating all possible disassembly sequences until a feasible disassembly sequence is found. During the tree search, the algorithm selects the sequence that can make S i The disassembly sequence that can remove the least number of 3D objects is selected, and the current disassembly sequence is updated to ensure that all 3D objects can be separated smoothly. In this way, the algorithm can dynamically adjust the disassembly sequence when there is an interference problem to ensure the disassembly of the entire packaging layout.

[0102] Step 5: Determine the accessible area around the placed 3D objects, and find the intersection of the accessible areas based on the accessible areas of all 3D objects to form a compact or loose cutting shell, and plan the cutting path based on the cutting shell. The accessible area is the voxel position that the cutting tool can access without obstacles, which is used to ensure that the cutting tool will not collide with the surrounding 3D objects during the cutting process. Cut the cutting shell along each cutting tool direction to generate a cutting contour perpendicular to the cutting tool direction as the actual cutting path.

[0103] Step 5.1: Figure 5 As shown, for each 3D object S i , based on its tool collision field Γ C , identifying accessible areas around it. These areas are voxel locations that the tool can access without obstacles, ensuring that the tool does not collide with surrounding objects during the cutting process. Figure 5 (a) Input tool collision field, the red short lines represent feasible tool directions, and the blue voxels represent the connected parts of the target object and the adjacent unreachable areas; Figure 5 (b) generates a compact cutting shell by the intersection of all surrounding cutting angles, but the processing efficiency is low due to too many cutting planes; Figure 5 (c) generates a relaxed cutting shell by screening some cutting angles to reduce the number of cutting planes; Figure 5 (d) in the figure projects the connected area along the preset tool direction and extracts the green 2D inner area and the yellow boundary. Figure 5 The bottom right image in (d) shows the projection mapping; Figure 5 (e) in the figure extrude the projections in each direction into a 3D volume and find the intersection to form Figure 5 (e) Final cut shell in the bottom right image.

[0104] Among them, any voxel block in the accessible area, that is, Figure 5 The white voxel blocks in the image have an endpoint and two rays emitted by it (only one ray is considered as two identical rays), that is, any voxel block in the accessible area can generate a cutting angle. Figure 5 As shown in (c), each yellow endpoint plus the two rays emitted by it constitute a cutting angle, and the intersection of multiple cutting angles constitutes a cutting shell.

[0105] However, too many cutting angles will increase unnecessary calculation amount, so in this embodiment, only a few accessible area voxel blocks are selected as cutting angles to form the cutting shell.

[0106] Figure 5 Each red ray in each white voxel block in (a) represents that the tool can access the voxel position unimpeded along the reverse direction of the ray, so the white voxel block is accessible to the tool. All white voxel blocks constitute the accessible area.

[0107] Step 5.2: Compact or loose cutting shell means that by dividing the 3D object S i Merges with its surrounding accessible area to form a compact cutting enclosure C H (S i ). This shell consists of multiple cutting planes, ensuring that the tool can access and cut the object from multiple directions. A compact cutting shell can maximize space utilization, but it may increase the number of cutting planes, resulting in reduced processing efficiency, and because the cutting tool must ensure that it does not collide with the 3D object. In order to reduce the number of cutting planes, some accessible areas can be randomly selected as cutting angles until these cutting angles intersect to form a closed shell, that is, a loose cutting shell is generated. Although this shell has fewer cutting planes, it still ensures the accessibility of the tool and the detachability of the object. Therefore, the looseness or compactness of the cutting shell can be adjusted according to actual conditions.

[0108] Step 5.3: Cut the shell C according to the generated H (S i), for each tool direction C i Plan the cutting path. Specifically, Figure 6 It means that the cutter cuts along the black outline of the outer ring layer by layer in one direction. For each projection direction of the cuttable shell, the following steps are performed: Figure 6 The cuts shown in the figure are used to segment the model. Figure 6 As shown in the figure, the cutting shell is cut along each cutting tool direction, and a series of cutting contours perpendicular to the cutting tool direction are generated as the actual cutting path. Finally, the cutting shell C of each 3D object is output. H (S i ) and their corresponding cutting paths to ensure that all objects can be separated from the raw materials smoothly.

[0109] Step 6: Cut the 3D object according to the packing layout, cutting shell and cutting path.

[0110] In a specific embodiment, Figure 7 As shown in the figure, the left side is the 3D model to be packaged, the middle is the packaging result of all 3D models according to the method of this embodiment and its enlarged image, and the right side is the corresponding cuttable shell result under the packaging layout. After completing the placement of all objects and the generation of cuttable shells, the algorithm outputs the overall packaging layout, showing the position and direction of all objects in the container, ensuring that the space utilization is maximized and each object meets the detachability constraint. At the same time, the cuttable shell C of each object is output. H (S i ) and its corresponding cutting paths, which consist of a series of cutting contours perpendicular to the tool direction, ensuring that the tool can efficiently cut the object and avoid collisions. Finally, the algorithm verifies the disassembly of the overall layout, generates a detailed report containing 3D models, cutting paths, space utilization, and processing time estimates, and outputs it to the manufacturing system for actual processing operations on CNC machine tools. Through this process, the algorithm achieves a balance between high space utilization and high processing efficiency, providing a complete solution for the packaging and cutting of complex 3D objects.

[0111] Embodiment 2:

[0112] Embodiment 2 of the present invention provides a 3D irregular object packaging system for subtractive manufacturing, including:

[0113] The collision area generation module is configured to obtain container raw materials and 3D objects to be packaged, and determine the placement order of the 3D objects; calculate the collision-free space according to the container and the 3D objects, and preliminarily generate the collision-free area; further screen the collision-free area according to the operating distance of the cutting tool to form candidate placement positions;

[0114] A packing layout generation module is configured to sort candidate positions according to Euclidean distance, place 3D objects one by one according to the sorting results, and adjust the placed 3D objects according to the disassembly order during the placement process to form a packing layout;

[0115] a path planning module configured to determine accessible areas around the placed 3D objects, form a cutting shell based on the accessible areas of all 3D objects, and plan a cutting path based on the cutting shell;

[0116] The cutting module is configured to cut the 3D object according to the packaging layout, the cutting shell and the cutting path.

[0117] Embodiment three:

[0118] Embodiment 3 of the present invention provides a medium on which a program is stored. When the program is executed by a processor, the steps of the 3D irregular object packaging method for subtractive manufacturing as described in Embodiment 1 of the present invention are implemented.

[0119] Embodiment 4:

[0120] Embodiment 4 of the present invention provides a device, including a memory, a processor, and a program stored in the memory and executable on the processor. When the processor executes the program, the steps in the 3D irregular object packaging method for subtractive manufacturing as described in Embodiment 1 of the present invention are implemented.

[0121] The steps involved in the above embodiments 2, 3 and 4 correspond to the method embodiment 1. For the specific implementation methods, please refer to the relevant description part of embodiment 1.

[0122] Those skilled in the art should understand that the modules or steps of the present invention described above can be implemented by a general-purpose computer device, or alternatively, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. The present invention is not limited to any specific combination of hardware and software.

[0123] Although the above describes the specific implementation mode of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. A 3D irregular object packaging method for subtractive manufacturing, characterized in that: The following steps are involved: Obtain container raw materials and 3D objects to be packaged, and determine the placement order of the 3D objects; Calculate the collision-free space based on the container and 3D objects, and preliminarily generate the collision-free area; The collision-free area is further screened according to the operating distance of the cutting tool to form candidate placement positions; Sort candidate locations according to Euclidean distance, place 3D objects one by one according to the sorting results, and adjust the placed 3D objects according to the disassembly order during the placement process to form a packaged layout; Determine the accessible area around the placed 3D objects, form a cutting shell according to the accessible areas of all 3D objects, and plan a cutting path according to the cutting shell; Cut 3D objects according to packing layout, cutting shell and cutting path.

2. The 3D irregular object packaging method for subtractive manufacturing according to claim 1, characterized in that: The specific steps for calculating collision-free space based on containers and 3D objects are: voxelize the container and the 3D object to obtain the voxel grid of the new object and the voxel grid of the placed object; The collision relationship between new objects and already placed objects in the voxel grid is calculated through a convolution method to initially generate collision-free areas.

3. The 3D irregular object packaging method for subtractive manufacturing according to claim 1, characterized in that: The specific steps for further screening the collision-free area according to the operating distance of the cutting tool are: The distance field is calculated by calculating the distance of each voxel point to the nearest placed object; The distance field results are further filtered according to the operating distance of the cutting tool to obtain candidate placement locations.

4. The 3D irregular object packaging method for subtractive manufacturing according to claim 1, characterized in that: The specific steps to adjust the placed 3D objects according to the disassembly order during the placement process are: Place objects while verifying removability using removability constraints; When there are interference issues, a tree search structure is used to adjust the placed 3D objects.

5. The 3D irregular object packaging method for subtractive manufacturing according to claim 1, characterized in that: The accessible area is the voxel position that the cutting tool can access without obstacles, which is used to ensure that the cutting tool does not collide with surrounding objects during the cutting process.

6. The 3D irregular object packaging method for subtractive manufacturing according to claim 1, characterized in that: Compact or loose cut shells are formed according to the accessible areas of all 3D objects.

7. The 3D irregular object packaging method for subtractive manufacturing according to claim 1, characterized in that: The specific steps for planning the cutting path according to the cutting shell are: The cutting shell is cut along each cutting tool direction, and a cutting contour perpendicular to the cutting tool direction is generated as an actual cutting path.

8. A 3D irregular object packaging system for subtractive manufacturing, characterized in that: include: A collision area generation module is configured to obtain container raw materials and 3D objects to be packaged, and determine a placement order of the 3D objects; Calculate the collision-free space based on the container and the 3D object, and preliminarily generate the collision-free area; further screen the collision-free area based on the operating distance of the cutting tool to form candidate placement positions; A packing layout generation module is configured to sort candidate positions according to Euclidean distance, place 3D objects one by one according to the sorting results, and adjust the placed 3D objects according to the disassembly order during the placement process to form a packing layout; a path planning module configured to determine accessible areas around the placed 3D objects, form a cutting shell based on the accessible areas of all 3D objects, and plan a cutting path based on the cutting shell; The cutting module is configured to cut the 3D object according to the packaging layout, the cutting shell and the cutting path.

9. A computer-readable storage medium, characterized in that: A plurality of instructions are stored therein, and the instructions are suitable for being loaded by a processor of a terminal device and executing the 3D irregular object packaging method for subtractive manufacturing as described in any one of claims 1-7.

10. A terminal device, characterized in that: It includes a processor and a computer-readable storage medium, the processor is used to implement each instruction; the computer-readable storage medium is used to store multiple instructions, and the instructions are suitable for being loaded by the processor and executed by the 3D irregular object packaging method for subtractive manufacturing described in any one of claims 1-7.

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