A 3D irregular object packing method and system for subtractive manufacturing

Abstract

The application discloses a kind of 3D irregular object packing methods and systems for subtractive manufacturing, and relates to subtractive manufacturing technical field.The method includes the following steps: obtaining container raw materials and 3D objects to be packed;According to container and 3D object, collision-free space is calculated, and collision-free region is initially generated;According to the operation distance of cutting tool, the collision-free region is further filtered to form candidate placement position;According to the Euclidean distance, the candidate position is sorted to form packing layout;According to the accessible region of all 3D objects, cutting shell is formed, and cutting path is planned according to cutting shell;According to packing layout, cutting shell and cutting path, 3D object is cut.The application solves the limitations of traditional packing algorithm in subtractive manufacturing, and also provides a new solution for efficient and accurate manufacturing process.

Description

Technical Field

[0001] This invention relates to the field of subtractive manufacturing technology, and in particular to a method and system for packaging 3D irregular objects for subtractive manufacturing. Background Technology

[0002] The statements in this section are merely 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, efficiently and accurately cutting multiple workpieces from raw materials is a key challenge. Traditional subtractive manufacturing processes typically include two stages: roughing and finishing. Roughing primarily removes excess material quickly, while finishing focuses on improving the surface quality and geometric accuracy of the workpieces. However, the pre-processing stage of raw materials (i.e., cutting multiple workpieces from a large block of raw material) before roughing and finishing plays a crucial 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 using the Cutting Stock Problem (CSP) model. The core objective of the CSP problem is to minimize material waste and maximize the utilization rate of raw materials. This problem has been widely applied in many industries, such as papermaking, steel, glass, and wood processing. However, although one-dimensional and two-dimensional CSP problems have been extensively studied, the CSP problem for three-dimensional irregular objects remains a complex and underexplored area, especially when considering tool collisions and interference between objects.

[0005] While existing 3D object packing algorithms have made some progress in terms of space utilization, avoiding object overlap, and object disassembly, these algorithms often do not fully consider the process constraints of subtractive manufacturing, particularly how to ensure smooth disassembly of objects during cutting and how to avoid collisions between cutting tools and objects. Therefore, existing algorithms often cannot simultaneously satisfy high space utilization and process constraints, leading to problems such as material waste or tool damage during production.

[0006] Furthermore, most current 3D packaging methods focus only on the geometry of objects, neglecting 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 are limited in their effectiveness when dealing with irregularly shaped objects and cannot guarantee the cutability of these objects in actual processing (i.e., whether they can be successfully processed using cutting tools).

[0007] In conclusion, how to ensure high space utilization during the cutting process of irregular three-dimensional objects while also enabling all objects to be disassembled smoothly has become a technical problem that needs to be solved by existing technologies. Summary of the Invention

[0008] To address the shortcomings of existing technologies, the purpose of this invention is to provide a method and system for packaging 3D irregular objects in subtractive manufacturing. This method combines the 3D packaging 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 overcomes the limitations of traditional packaging algorithms in subtractive manufacturing but also provides a new solution for efficient and precise manufacturing processes.

[0009] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0010] The first aspect of this invention provides a method for packaging 3D irregular objects for subtractive manufacturing, comprising the following steps:

[0011] Obtain the container raw materials and the 3D objects to be packaged, and determine the placement order of the 3D objects;

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

[0013] Based on the operating distance of the cutting tool, the non-collision area is further screened to form candidate placement positions;

[0014] Candidate positions are sorted according to Euclidean distance, and 3D objects are placed one by one according to the sorting results. During the placement process, the placed 3D objects are adjusted according to the disassembly order to form a packaged layout.

[0015] Determine the accessible area around the placed 3D object, construct a cutting shell based on the accessible areas of all 3D objects, and plan the cutting path based on the cutting shell;

[0016] Cut 3D objects based on the packaging layout, cut shell, and cut path.

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

[0018] Voxelization is performed on the container and 3D object to obtain the voxel mesh of the new object and the voxel mesh of the placed object;

[0019] The collision relationship between new objects and existing objects in the voxel mesh is calculated using the convolution method, and a collision-free region is initially generated.

[0020] Furthermore, the specific steps for further screening of collision-free areas based on the operating distance of the cutting tool are as follows:

[0021] The distance field is calculated by measuring the distance between each voxel and the nearest placed object;

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

[0023] Furthermore, the specific steps for adjusting the placed 3D objects according to the disassembly sequence during the placement process are as follows:

[0024] Place the object while verifying its removability using the removability constraint;

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

[0026] Furthermore, the accessible area is the voxel location where the cutting tool can be accessed without obstruction, ensuring that the cutting tool does not collide with surrounding objects during the cutting process.

[0027] Furthermore, a compact or loose cut-out shell is constructed based on the accessible area of ​​all 3D objects.

[0028] Furthermore, the specific steps for planning the cutting path based on the cutting shell are as follows:

[0029] The outer shell is cut along each cutting tool direction to generate a cutting profile perpendicular to the cutting tool direction, which serves as the actual cutting path.

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

[0031] The collision area generation module is configured to acquire 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 to initially generate collision-free areas; and further filter the collision-free areas based on the operating distance of the cutting tool to form candidate placement positions.

[0032] The package 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 package layout.

[0033] The path planning module is configured to determine the accessible area around the placed 3D object, construct a cutting shell based on the accessible areas of all 3D objects, and plan the cutting path based on the cutting shell.

[0034] The cutting module is configured to cut 3D objects based on the packing layout, cutting shell, and 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 method for packaging 3D irregular objects for subtractive manufacturing as described in the first aspect of the present invention.

[0036] A fourth aspect of the present invention provides an apparatus including a memory, a processor, and a program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of the method for packaging 3D irregular objects for subtractive manufacturing as described in the first aspect of the present invention.

[0037] The above one or more technical solutions have the following beneficial effects:

[0038] This invention discloses a method and system for packaging 3D irregular objects for subtractive manufacturing. By optimizing the placement order of objects and generating the cut outer shell, it can maximize material utilization and reduce waste within a limited space. It is particularly suitable for manufacturing scenarios using expensive or scarce materials, significantly reducing material costs.

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

[0040] This invention's algorithm is applicable not only to regularly shaped objects but also to complex free-form surfaces and CAD models, making it suitable for various manufacturing fields such as graphite bearing manufacturing, jade carving, and foam product manufacturing. Through voxelization and convolution methods, it achieves efficient collision detection and path planning, automates the packing of large-scale objects, possesses good scalability, and is suitable for industrial applications.

[0041] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0042] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0043] Figure 1 This is a schematic diagram of the packaging method for 3D irregular objects in subtractive manufacturing according to Embodiment 1 of the present invention;

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

[0045] Figure 3 This is a schematic diagram illustrating the possible placement locations of the generated model according to Embodiment 1 of the present invention;

[0046] Figure 4 This is a schematic diagram illustrating the dynamic adjustment of disassembly order via tree search in Embodiment 1 of the present invention;

[0047] Figure 5 This is a schematic diagram illustrating the generation of a cuttable outer shell according to Embodiment 1 of the present invention;

[0048] Figure 6 This is a schematic diagram of cutting along the cuttable outer shell according to Embodiment 1 of the present invention;

[0049] Figure 7 This is a diagram showing a portion of the calculation results from an embodiment of the present invention. Detailed Implementation

[0050] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0051] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0052] Example 1:

[0053] Existing packing algorithms typically focus only on space utilization and avoiding object overlap, failing to effectively consider the accessibility of cutting tools and the disassembly of objects. Therefore, this invention aims to propose a new algorithm that maximizes space utilization while ensuring that each object does not collide during processing and can be easily disassembled. The objectives of this method are: (1) to efficiently pack irregularly shaped objects in three-dimensional space to maximize space utilization; (2) to ensure that the packed objects can be easily cut during subtractive manufacturing, i.e., to avoid collisions between cutting tools and objects and to ensure that each object can be easily disassembled; and (3) to propose a new geometric shell structure that combines the geometry of irregular objects and the accessibility of cutting tools to guide the planning of cutting paths and the disassembly sequence of objects.

[0054] Based on the above objectives, Embodiment 1 of the present invention provides a method for packaging 3D irregular objects for subtractive manufacturing. This method introduces a cutting shell to ensure that the 3D irregular object can be smoothly cut and separated after packaging, while maximizing space utilization and improving processing efficiency. It is applicable to various 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 mesh structure; Figure 1 (b) Then, according to the order of object size from largest to smallest, the objects are packed sequentially using a greedy algorithm; Figure 1 (c) For each packaged 3D object, generate a cuttable shell based on the current layout; Figure 1 (d) for the placement of a single new object: First, a collision-free space is generated, and then the optimal placement position is found by calculating the distance field of that space, while ensuring that the requirements of being cuttable and collision-free are met in the process.

[0056] Specifically, the following steps are included:

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

[0058] In one specific implementation, a container raw material A with fixed boundaries and a 3D object S = {S1, S2, ..., S...} to be packaged are provided. m The placement order is determined, and in subsequent processing steps such as convolution calculation of collision-free regions, the constraint condition is that the model cannot collide with the boundary.

[0059] Specifically, the placement order of 3D objects is determined by their volume from largest to smallest. Sorting the 3D objects to be packaged by volume from largest to smallest maximizes space utilization. Placing larger objects first ensures they occupy appropriate positions, while smaller objects more easily fill remaining gaps, avoiding wasted space and reducing the complexity and computational load of subsequent placement.

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

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

[0062] Step 2.1: Perform voxelization on the container and 3D object to obtain the voxel mesh of the new object and the voxel mesh of the placed object.

[0063] In one specific implementation, such as Figure 1 As shown in (1), the container and each 3D object are voxelized. Converting continuous geometry into discrete voxel forms makes these geometries easier to collide with and perform spatial calculations. Specifically, taking 3D object S... i For example, each 3D object S i It will be represented as a voxel grid Here, x is a voxel point in the grid:

[0064]

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

[0066]

[0067] In this embodiment, 3D objects are packaged and placed into the container in sequence, one 3D object at a time. The objects that have been placed are those that have already been placed, and the objects that have not been placed are those that will be placed in this time.

[0068] Perform the same voxelization process as described above on the container.

[0069] Step 2.2: Calculate the collision relationship between the new object and the already placed objects in the voxel mesh using the convolution method to initially generate collision-free regions.

[0070] like Figure 2 As shown, convolution operations are used to compute the collision-free space. Figure 2 This demonstrates the process of generating a collision-free space based on convolution. First, the input object is voxelized at the top left and bottom left corners of the image, and then convolution is used to assign a value of -1 to collision voxels and a value of 0 to non-collision voxels. The upper part of the image represents the initial white area of ​​the collision-free placement space. Subsequently, constraints of the distance field and tool width are added to further refine the collision-free placement space. The right side of the image represents the final white area of ​​the tool's collision-free placement space. This process ensures that the object avoids collisions with other objects and the tool during placement.

[0071] In one specific implementation, the core idea of ​​convolution is to positionally superimpose the voxel mesh of the new object with the voxel mesh of the already placed objects. If voxels overlap at a certain position, a collision is considered to have occurred at that position. The convolution result... The presence of a collision at grid point x is indicated by the following definition:

[0072]

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

[0074] Step 3: Further refine the collision-free areas based on the cutting tool's operating distance to create candidate placement locations. Specifically, detect collisions between the new object and already placed objects, and use the distance field to ensure the tool can reach the new object, ultimately forming feasible collision-free locations as candidate placement locations.

[0075] Step 3.1: Calculate the distance field by calculating the distance between each voxel and the nearest placed object.

[0076] In one specific implementation, after determining the collision-free space, a further constraint is ensuring that the cutting tool can reach every placement location. To evaluate the tool's accessibility, such as... Figure 2 As shown, the algorithm introduces a distance field to calculate the distance between each voxel and the nearest placed object. Distance Field Defined as:

[0077]

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

[0079] Step 3.2: Further filter the distance field results based on the operating distance of the cutting tool to obtain candidate placement positions.

[0080] In one specific implementation, the distance field results are further filtered to define the final feasible collision-free locations:

[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, the location is considered a feasible candidate placement location; otherwise, it will be excluded.

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

[0084] Step 4.1: Place the object and verify its detachability using the detachability constraint.

[0085] Step 4.1.1: As Figure 3 As shown, calculate the Euclidean distance for each candidate position. Figure 3 The process of the algorithm determining the placement of the model is demonstrated. Figure 3 The white area generated in (a) is a collision-free space; Figure 3 (b) Calculate the Euclidean distance field from each voxel to the lower left corner of the container; Figure 3 (c) in the middle combines distance information with the collision-free space to sort candidate positions; Figure 3 In (d), the red box marks the selection of a non-negative voxel position as the placement location for the new object; Figure 3 (e) shows the layout after placing the red triangle object in the selected position; Figure 3 (f) generates the tool collision field corresponding to this placement layout; Figure 3 (g) and Figure 3 (h) in the model analyzes the collision field through connected components; Figure 3 In the process, (i), (j), and (k) adjust the dismantling sequence to remove the preceding obstacle; ultimately, in Figure 3 In (l), the red object satisfies the cuttable constraint.

[0086] For each voxel position p in the candidate placement location i Calculate the Euclidean distance from it to voxel p0 at the bottom left corner of the container:

[0087]

[0088] Where x represents a voxel in three-dimensional space, and |x-p0| represents the Euclidean distance from x to p0.

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

[0090]

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

[0092] Step 4.1.3: For each tool direction C i Calculate its voxelized representation The collision field was calculated using a convolution method. Global tool collision field Γ C It is all Intersection:

[0093]

[0094] Check Γ C Does it exist in and I O Inaccessible voxels between them. If and I O If they are not in the same connected component, the packing layout G satisfies the tool collision-free constraint.

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

[0096] Step 4.1.4: If the packaging layout is... If the tool collision-free constraint is satisfied, then by adjusting I along each tool direction... O Perform a scanning operation and attempt to disassemble along each tool direction. If at least one direction allows for unobstructed disassembly Then package layout It satisfies the condition of having no interlocking constraints.

[0097] Step 4.1.5: If the current packaging layout is... If all disassembly constraints are satisfied, that is, if both the no-interlock constraint and the no-tool collision constraint are satisfied, then the 3D object S... i Add it before the disassembly sequence. If S i If the detachability constraint is not met, then step 4.2 is used to attempt to remove the preceding 3D object to make it detachable until a feasible detachment sequence is found.

[0098] Step 4.2: When interference issues exist, a tree search structure is used to adjust the placed 3D objects to ensure that all 3D objects can be successfully separated.

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

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

[0101] Specifically, first, attempt to remove one or more items located at S in the disassembly sequence. i The 3D object in front or And re-verify S i The removability. If S i If disassembly still fails, continue removing more preceding 3D objects. To systematically explore all possible disassembly sequences, the algorithm employs a tree search structure, treating each possible disassembly sequence as a node in a tree, starting from the current layout. The algorithm begins by recursively generating all possible disassembly sequences until a feasible disassembly sequence is found. During the tree search process, the algorithm selects sequences that allow S to... i The algorithm selects the disassembly sequence that removes the fewest 3D objects and updates the current disassembly order to ensure that all 3D objects can be successfully separated. In this way, the algorithm can dynamically adjust the disassembly order when interference issues exist, ensuring the disassembly capability of the entire packaged layout.

[0102] Step 5: Determine the accessible regions around the placed 3D objects. Based on the accessible regions of all 3D objects, calculate the intersection of these regions to form a compact or relaxed cutting shell. Plan the cutting path based on the cutting shell. The accessible region refers to the voxel positions where the cutting tool can access the cutting area without obstruction, ensuring that the cutting tool does not collide with surrounding 3D objects during the cutting process. Cut along each cutting tool direction to generate a cutting profile perpendicular to the cutting tool direction, which serves as the actual cutting path.

[0103] Step 5.1: As Figure 5 As shown, for each 3D object S i Based on its tool collision field Γ C It identifies the accessible area around the cutting tool. These areas are voxel locations that the tool can access without obstruction, ensuring that the tool does not collide with surrounding objects during cutting. Figure 5 (a) is the input tool collision field, where the red short line indicates the feasible tool direction and the blue voxel represents the connected part between the target object and the adjacent unreachable region; Figure 5 (b) generates a compact cut shell by the intersection of all surrounding cut angles, but the excessive number of cut planes leads to low processing efficiency; Figure 5 (c) generates a relaxed cutting shell by filtering some cutting angles, thus reducing the number of cutting planes; Figure 5 (d) Project the connected region along the preset tool direction, and extract the green 2D inner region and the yellow boundary. Figure 5 The bottom right image in (d) shows the projection mapping; Figure 5 In step (e), the projections in each direction are extruded into 3D volumes and their intersections are found, forming... Figure 5 The final cut shell is shown in the bottom right image (e) of the middle section.

[0104] Among them, any voxel block in an accessible region, i.e. Figure 5 The white voxel blocks in the image all have an endpoint and two rays emanating from it (if there is only one ray, it is considered as two identical rays), meaning that any accessible voxel block can produce a cutting angle. For example... Figure 5 As shown in (c), each yellow endpoint plus the two rays emitted from it forms a cutting angle, and multiple cutting angles intersect to form a cutting shell.

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

[0106] Figure 5 In (a) of the diagram, each red ray within each white voxel represents a voxel location that the tool can access without obstruction along the opposite direction of that ray, thus making the white voxel accessible to the tool. All the white voxels constitute the accessible region.

[0107] Step 5.2: Compact or loose cut-out shell means, by cutting the 3D object S i It merges with its surrounding accessible area to form a compact cut-out shell C. H (S i This outer shell consists of multiple cutting planes, ensuring the tool can access and cut the object from multiple directions. A compact cutting shell maximizes space utilization but may increase the number of cutting planes, leading to reduced machining efficiency, especially since the cutting tool must avoid collisions with the 3D object. To reduce the number of cutting planes, some accessible areas can be randomly selected as cutting angles until these angles intersect to form a closed shell, creating a relaxed cutting shell. This shell, while having fewer cutting planes, still ensures tool accessibility and object removability. Therefore, the degree of relaxation or compactness of the cutting shell can be adjusted according to specific circumstances.

[0108] Step 5.3: Based on the generated cut shell C H (S i ), for each tool direction C i Plan the cutting path. Specifically... Figure 6 This indicates that the cutting tool delves deeper layer by layer along the outer black outline to complete a cut in one direction. For each projected direction of the cuttable shell, this process is performed as follows: Figure 6 The cuts shown are used to segment the model. According to... Figure 6 The cutting shell is cut along each cutting tool direction, generating a series of cutting contours perpendicular to the cutting tool direction, which serve as the actual cutting path. Finally, the cut shell C of each 3D object is output. H (S i (and its corresponding cutting path) to ensure that all objects can be successfully separated from the raw materials.

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

[0110] In one specific implementation, such as Figure 7 As shown, the left side displays the 3D model to be packaged, the middle side shows the packaged result of all 3D models according to the method of this embodiment and its enlarged view, and the right side shows the corresponding cuttable shell result under this packaging layout. After completing the placement of all objects and generating the cuttable shell, the algorithm outputs the overall packaging layout, showing the position and orientation of all objects in the container, ensuring maximum space utilization and that each object meets the detachability constraint. Simultaneously, it outputs the cuttable shell C for each object. H (S i The algorithm generates a 3D model 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 detachability of the overall layout, generates a detailed report including the 3D model, cutting paths, space utilization, and machining time estimates, and outputs it to the manufacturing system for actual machining operations on the CNC machine tool. Through this process, the algorithm achieves a balance between high space utilization and high machining efficiency, providing a complete solution for the packaging and cutting of complex 3D objects.

[0111] Example 2:

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

[0113] The collision area generation module is configured to acquire 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 to initially generate collision-free areas; and further filter the collision-free areas based on the operating distance of the cutting tool to form candidate placement positions.

[0114] The package 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 package layout.

[0115] The path planning module is configured to determine the accessible area around the placed 3D object, construct a cutting shell based on the accessible areas of all 3D objects, and plan the cutting path based on the cutting shell.

[0116] The cutting module is configured to cut 3D objects based on the packing layout, cutting shell, and cutting path.

[0117] Example 3:

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

[0119] Example 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, it implements the steps in the method for packaging 3D irregular objects for subtractive manufacturing as described in Embodiment 1 of the present invention.

[0121] The steps and methods involved in Examples 2, 3 and 4 above correspond to those in Example 1. For specific implementation details, please refer to the relevant description section of Example 1.

[0122] Those skilled in the art will understand that the modules or steps of the present invention described above can be implemented using general-purpose computer devices. Optionally, they can be implemented using computer-executable program code, thereby allowing them to be stored in a storage device for execution by a computer device, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. The present invention is not limited to any particular combination of hardware and software.

[0123] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this 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 without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for packaging 3D irregular objects for subtractive manufacturing, characterized in that, Includes the following steps: Obtain the container raw materials and the 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 object, and initially generate the collision-free area; Based on the operating distance of the cutting tool, the non-collision area is further screened to form candidate placement positions; Candidate positions are sorted according to Euclidean distance, and 3D objects are placed one by one according to the sorting results. During the placement process, the placed 3D objects are adjusted according to the disassembly order to form a packaged layout. Determine the accessible area around the placed 3D object, construct a cutting shell based on the accessible areas of all 3D objects, and plan the cutting path based on the cutting shell; Cut 3D objects based on the packaging layout, cut shell, and cut path.

2. The method for packaging 3D irregular objects for subtractive manufacturing as described in claim 1, characterized in that, The specific steps for calculating a collision-free space based on containers and 3D objects are as follows: Voxelization is performed on the container and 3D object to obtain the voxel mesh of the new object and the voxel mesh of the placed object; The collision relationship between new objects and existing objects in the voxel mesh is calculated using the convolution method, and a collision-free region is initially generated.

3. The method for packaging 3D irregular objects for subtractive manufacturing as described in claim 1, characterized in that, The specific steps for further screening of non-collision areas based on the operating distance of the cutting tool are as follows: The distance field is calculated by measuring the distance between each voxel and the nearest placed object; The distance field results are further filtered based on the operating distance of the cutting tool to obtain candidate placement positions.

4. The method for packaging 3D irregular objects for subtractive manufacturing as described in claim 1, characterized in that, The specific steps for adjusting the placed 3D objects according to the disassembly sequence during placement are as follows: Place the object while verifying its removability using the removability constraint; When interference issues exist, a tree search structure is used to adjust the placed 3D objects.

5. The method for packaging 3D irregular objects for subtractive manufacturing as described in claim 1, characterized in that, The accessible area is the voxel location where the cutting tool can access the cutting tool without obstruction, ensuring that the cutting tool does not collide with surrounding objects during the cutting process.

6. The method for packaging 3D irregular objects for subtractive manufacturing as described in claim 1, characterized in that, A compact or loose cut-out shell is constructed based on the accessible area of ​​all 3D objects.

7. The method for packaging 3D irregular objects for subtractive manufacturing as described in claim 1, characterized in that, The specific steps for planning the cutting path based on the cutting shell are as follows: The outer shell is cut along each cutting tool direction to generate a cutting profile perpendicular to the cutting tool direction, which serves as the actual cutting path.

8. A packaging system for 3D irregular objects for subtractive manufacturing, characterized in that, include: The collision region generation module is configured to acquire the container raw materials and the 3D objects to be packaged, and determine the placement order of the 3D objects; The collision-free space is calculated based on the container and 3D object to initially generate a collision-free area; the collision-free area is further filtered based on the operating distance of the cutting tool to form candidate placement positions; The package 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 package layout. The path planning module is configured to determine the accessible area around the placed 3D object, construct a cutting shell based on the accessible areas of all 3D objects, and plan the cutting path based on the cutting shell. The cutting module is configured to cut 3D objects based on the packing layout, cutting shell, and cutting path.

9. A computer-readable storage medium, characterized in that, It stores multiple instructions, which are adapted to be loaded and executed by the processor of a terminal device as described in any one of claims 1-7, for packaging 3D irregular objects for subtractive manufacturing.

10. A terminal device, characterized in that, The invention includes a processor and a computer-readable storage medium, the processor being used to implement various instructions; the computer-readable storage medium being used to store multiple instructions adapted for loading and execution by the processor of the method for packaging 3D irregular objects for subtractive manufacturing as described in any one of claims 1-7.

Images