An efficient interference inspection method for complex structural CAD models

Abstract

This invention belongs to the field of CAD manufacturing information technology and relates to an efficient interference inspection method for complex structural CAD models. It employs a collision detection optimization algorithm using a layered bounding box assembly tree and synchronous recursive descent, comprising the following steps: Step 1: Establishing quantitative evaluation indicators; Step 2: Optimizing the layered bounding box assembly tree algorithm; Step 3: Recursively applying the results of the optimized layered bounding box assembly tree algorithm using a synchronous recursive descent algorithm. This invention uses a collision detection optimization algorithm combining a layered bounding box assembly tree and synchronous recursive descent, and uses synchronous recursive descent to calculate the nodes to be compared, thus solving the problems of high time complexity and inability to effectively balance efficiency and accuracy in existing methods.

Description

Technical Field

[0001] This invention belongs to the field of CAD manufacturing information technology, and relates to an efficient interference inspection method for complex structural CAD models in CAD manufacturing. Background Technology

[0002] Currently, the 3D design software CATIA is widely used in the design of aircraft equipment shapes, structures, and systems. During aircraft manufacturing, interference frequently occurs between various components. Failure to promptly identify and correct these interferences can lead to serious consequences. However, the efficiency and accuracy of collision detection directly impact the efficiency of interference detection and are crucial indicators of user experience. Therefore, finding a balance between the efficiency and accuracy of collision detection is a problem that requires further research.

[0003] Boundary box algorithms are used to obtain the optimal boundary space of a model. The basic idea is to approximate objects with complex geometries using relatively large but simple geometric shapes such as spheres or cuboids. Common boundary box algorithms include boundary spheres, aligned-axis bounding boxes (AABB), and oriented bounding boxes (OBB), which are widely used in collision detection.

[0004] (1) Among these popular bounding box algorithms, the bounding ball is more efficient but less accurate and is usually used for the initial processing of objects in collision detection.

[0005] (2) The cuboid bounding box algorithm is used for subsequent processing because of its high accuracy.

[0006] a) In the cuboid bounding box algorithm, the AABB algorithm is relatively simple. It is a bounding box with one face parallel to the three planes of the absolute coordinate system in space. Therefore, it cannot be used as the optimal minimum bounding box.

[0007] b) OBB is a bounding box with higher precision compared to the bounding sphere and AABB. It can rotate arbitrarily according to the first torque of the object. Therefore, an OBB with an appropriate orientation matrix can be regarded as the optimal minimum bounding box of the geometric object.

[0008] However, while collision detection for complex bounding boxes has lower overhead, its construction time is long. Therefore, a hierarchical bounding box tree algorithm is needed to combine bounding boxes with a tree structure. In complex CAD models, when performing pairwise testing on objects composed of m geometric shapes, CATIA's own interference check directly checks each part pairwise, which is very time-consuming. By traversing the bounding boxes constructed at each level of the tree structure, the time complexity is reduced from O(n²) to O(logn), thus achieving bounding box traversal detection and reducing the complexity of detection.

[0009] While the hierarchical bounding box tree detection algorithm reduces time complexity, it impacts efficiency and accuracy, making it difficult to meet the requirements of efficient interference inspection methods for complex structural CAD models. Furthermore, the hierarchical bounding box tree algorithm requires re-partitioning the parts to generate new tree structures, failing to utilize the original assembly tree structure and hindering rapid and reasonable bounding box design for complex assembly trees. It also cannot effectively leverage CATIA's CAA-related interfaces.

[0010] Therefore, it is necessary to consider designing a collision detection optimization algorithm using hierarchical bounding box assembly trees and synchronous recursive descent for complex CAD assembly trees, in order to optimize the overall efficiency of CATIA for interference checks. Summary of the Invention

[0011] The purpose of this invention is to propose an efficient interference inspection method for complex structural CAD models. It adopts a collision detection optimization algorithm with hierarchical bounding box assembly tree and synchronous recursive descent, and uses synchronous recursive descent to calculate the nodes that need to be compared. This solves the problem that the existing methods have high time complexity and cannot effectively balance efficiency and accuracy.

[0012] Technical solution

[0013] An efficient interference checking method for complex structural CAD models is proposed, employing a collision detection optimization algorithm based on a hierarchical bounding box assembly tree and synchronous recursive descent. The method includes the following steps:

[0014] Step 1: Establish quantitative evaluation indicators;

[0015] Step 2: Optimize the hierarchical bounding box assembly tree algorithm;

[0016] Step 3: Recursively use the results of the optimized hierarchical bounding box assembly tree algorithm through the synchronous recursive descent algorithm.

[0017] Furthermore, step 1 specifically involves: recursively downloading the component models of the two complex structures that need to be compared, establishing a total cost formula for quantitative evaluation indicators to measure the overall performance of the algorithm, and simultaneously calculating the average depth of the assembly tree during the recursive download process.

[0018] Furthermore, the component assembly trees of the two complex structures that need to be compared are recursively downloaded separately. During the recursive download process, the average depth n of the tree is calculated based on the formula of the average path length to the leaf node.

[0019] Furthermore, the total cost formula for the quantitative evaluation index is Tcd = NpCp × NqCq, where Tcd refers to the overall performance of the algorithm; Np refers to the time for bounding box connection detection; Cp refers to the cost of bounding box collision detection; Nq refers to the number of geometric object collision detections; and Cq refers to the cost of geometric object collision detection.

[0020] Furthermore, step 2 specifically involves dividing the assembly tree into four layers (A, B, C, and D) based on the average depth n. For layer A, a spherical bounding box needs to be constructed; for layer B, an AABB bounding box needs to be constructed; for layer C, an OBB bounding box needs to be constructed; and for layer D, no bounding box is constructed. Instead, the nodes are directly traversed, and the interference check interface of CATIA CAA is called. Specifically, layer A represents the first n / 3-1 layers of the assembly tree, layer B represents layers n / 3 to 2n / 3-1 layers, layer C represents layers 2n / 3 to n-1 layers, and layer D represents the nth layer and below.

[0021] Furthermore, for step 2, if the average depth of the assembly tree is 3, the assembly tree is divided into three layers: A, B, and C. A spherical bounding box needs to be constructed for layer A, an AABB bounding box needs to be constructed for layer B, and no bounding box needs to be constructed for layer C. The nodes are directly traversed and the interference check interface of CATIA CAA is called. At this time, layer A is the first layer of the assembly tree, layer B is the second layer of the assembly tree, and layer C is the third layer and below of the assembly tree.

[0022] Furthermore, for step 2, if the average depth of the assembly tree does not exceed 2 and the maximum depth of the assembly tree does not exceed 3, the nodes are directly traversed and the interference check interface of CATIA CAA is called; if the average depth of the assembly tree does not exceed 2 and the maximum depth of the assembly tree exceeds 3, the assembly tree is divided into three layers, A, B, and C. For layer A, an AABB bounding box needs to be constructed, and for layer B, no bounding box needs to be constructed. The nodes are directly traversed and the interference check interface of CATIA CAA is called. At this time, layer A is the first layer of the assembly tree, and layer B is the second layer and below of the assembly tree.

[0023] Furthermore, step 3 specifically includes:

[0024] Step 3.1 Calculate the spherical bounding box of the root node of the assembly tree of the two complex structural assemblies to be compared;

[0025] Step 3.2: Determine whether the spherical bounding boxes of the root nodes of the two complex structural assemblies intersect. If they intersect, proceed to step 3.3; otherwise, the process ends.

[0026] Step 3.3: Optimize the results using the hierarchical bounding box assembly tree algorithm. By traversing the nodes layer by layer through the synchronous descent rule, the corresponding bounding boxes are calculated synchronously level by level, and the intersection status of the child nodes is detected.

[0027] Furthermore, in step 3.3, if the recursive traversal reaches a lower-level node that needs to be judged for interference at a level where a bounding box does not need to be constructed, there are three cases: 1) When both nodes are leaf nodes, perform interference check directly; 2) When either of the two nodes is a leaf node A, recursively traverse the other node B, find all the leaf nodes obtained from the traversal, and perform interference check with leaf node A; 3) When neither node is a leaf node, recursively traverse the two nodes A and B, find all the leaf nodes obtained from the traversal of node A, and perform interference check with all the leaf nodes obtained from the traversal of node B.

[0028] If the recursive traversal reaches a lower-level node that needs to be judged for interference at a level where a bounding box needs to be built, but any node is a leaf node C, then construct an OBB bounding box for that leaf node, calculate the bounding box of the other node, and determine whether they intersect. If they intersect, recursively traverse that node, simultaneously construct the bounding box of the corresponding level, and determine whether it intersects with leaf node C, until the recursion reaches a level where no bounding box needs to be built. Then, recursively traverse the nodes that need to be compared at that level, find all the leaf nodes obtained from the traversal, and perform interference checks with leaf node C.

[0029] Beneficial effects

[0030] This invention proposes an efficient interference inspection method for complex structural CAD models. It employs a hierarchical bounding box assembly tree and a synchronous recursive descent collision detection optimization algorithm. The principle of the hierarchical bounding box tree algorithm is to combine bounding boxes with a tree structure. When performing pairwise testing on objects composed of m geometric shapes, without reconstructing the assembly tree, the hierarchical bounding box tree algorithm reduces the time complexity from O(n²) to O(logn), thereby achieving bounding box traversal detection and reducing the complexity of the detection process.

[0031] The method of this invention establishes a total cost formula as a quantitative evaluation index to measure the overall performance of the algorithm. During the recursive process, the average depth of the tree and the spatial weight of the parts at each node are statistically analyzed to determine appropriate algorithm parameters. This invention also employs a synchronous descent rule for traversing nodes in the assembly tree, improving the efficiency and accuracy of collision detection. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of a traditional binary hierarchical bounding box tree provided in an embodiment of the present invention.

[0033] Figures 2(a) and 2(b) are schematic diagrams of the original assembly tree and the hierarchical enclosing tree based on the assembly tree provided in the embodiments of the present invention.

[0034] Figure 3 This is a schematic diagram illustrating an example of a collision detection optimization algorithm based on a hierarchical bounding box assembly tree and synchronous recursive descent, provided in an embodiment of the present invention. Detailed Implementation

[0035] The features and illustrative embodiments of various aspects of the present invention will now be described in detail. Numerous specific details are set forth in the following detailed description to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of the invention by illustrating examples of the invention. The invention is by no means limited to any specific setups and methods set forth below, but covers any improvements, substitutions, and modifications to structures, methods, and devices without departing from the spirit of the invention. Well-known structures and techniques are not shown in the drawings and the following description to avoid unnecessarily obscuring the invention.

[0036] It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other, and the various embodiments can be referenced and cited in each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0037] Example 1:

[0038] An efficient interference inspection method for complex structural CAD models is provided, employing a collision detection optimization algorithm based on a hierarchical bounding box assembly tree and synchronous recursive descent, comprising the following steps:

[0039] Step 1: Establish quantitative evaluation indicators; This step specifically involves: recursively downloading the component models of two complex structures to be compared, establishing a total cost formula for quantitative evaluation indicators to measure the overall performance of the algorithm, and simultaneously calculating the average depth of the assembly tree during the recursive download process.

[0040] In this process, the component assembly trees of the two complex structures that need to be compared are downloaded recursively. During the recursive download process, the average depth n of the tree is calculated based on the formula of the average path length to the leaf node.

[0041] The total cost formula for the quantitative evaluation index is Tcd = NpCp × NqCq, where Tcd refers to the overall performance of the algorithm; Np refers to the time for bounding box connection detection; Cp refers to the cost of bounding box collision detection; Nq refers to the number of geometric object collision detections; and Cq refers to the cost of geometric object collision detection.

[0042] Step 2: Optimize the hierarchical bounding box assembly tree algorithm;

[0043] Step 2 specifically involves dividing the assembly tree into four layers (A, B, C, and D) based on its average depth n. For layer A, a spherical bounding box needs to be constructed; for layer B, an AABB bounding box needs to be constructed; for layer C, an OBB bounding box needs to be constructed; and for layer D, no bounding box is constructed. Instead, the nodes are directly traversed, and the interference check interface of CATIA CAA is called. Specifically, layer A represents the first n / 3-1 layers of the assembly tree, layer B represents layers n / 3 to 2n / 3-1 layers, layer C represents layers 2n / 3 to n-1 layers, and layer D represents the nth layer and below.

[0044] If the average depth of the assembly tree is 3, the assembly tree is divided into three layers: A, B, and C. A spherical bounding box needs to be constructed for layer A, an AABB bounding box needs to be constructed for layer B, and no bounding box needs to be constructed for layer C. Instead, the nodes are traversed directly and the interference check interface of CATIA CAA is called. At this time, layer A is the first layer of the assembly tree, layer B is the second layer of the assembly tree, and layer C is the third layer and below of the assembly tree.

[0045] In step 2, if the average depth of the assembly tree does not exceed 2 and the maximum depth of the assembly tree does not exceed 3, the nodes are directly traversed and the interference check interface of CATIA CAA is called. If the average depth of the assembly tree does not exceed 2 and the maximum depth of the assembly tree exceeds 3, the assembly tree is divided into three layers: A, B, and C. For layer A, an AABB bounding box needs to be constructed, while for layer B, no bounding box is constructed. The nodes are directly traversed and the interference check interface of CATIA CAA is called. In this case, layer A is the first layer of the assembly tree, and layer B is the second layer and below of the assembly tree.

[0046] Step 3: Using the synchronous recursive descent algorithm, recursively apply the results of the optimized hierarchical bounding box assembly tree algorithm, including:

[0047] Step 3.1 Calculate the spherical bounding box of the root node of the assembly tree of the two complex structural assemblies to be compared;

[0048] Step 3.2: Determine whether the spherical bounding boxes of the root nodes of the two complex structural assemblies intersect. If they intersect, proceed to step 3.3; otherwise, the process ends.

[0049] Step 3.3: Optimize the results using a hierarchical bounding box assembly tree algorithm. The algorithm recursively traverses nodes layer by layer using a synchronous descent rule, synchronously calculating the corresponding bounding boxes at each level and detecting the intersection status of child nodes. In this step, if the recursive traversal reaches a lower-level node that needs interference judgment at a level where bounding boxes do not need to be constructed, there are three cases: 1) When both nodes are leaf nodes, directly perform interference checks; 2) When either node is a leaf node A, recursively traverse the other node B, finding all leaf nodes obtained from the traversal and performing interference checks with leaf node A; 3) When neither node is a leaf node, recursively traverse both nodes A and B, finding all leaf nodes obtained from the traversal of node A and performing interference checks with all leaf nodes obtained from the traversal of node B.

[0050] If the recursive traversal reaches a lower-level node that needs to be judged for interference at a level where a bounding box needs to be built, but any node is a leaf node C, then construct an OBB bounding box for that leaf node, calculate the bounding box of the other node, and determine whether they intersect. If they intersect, recursively traverse that node, simultaneously construct the bounding box of the corresponding level, and determine whether it intersects with leaf node C, until the recursion reaches a level where no bounding box needs to be built. Then, recursively traverse the nodes that need to be compared at that level, find all the leaf nodes obtained from the traversal, and perform interference checks with leaf node C.

[0051] Example 2:

[0052] An efficient interference checking method for complex structural CAD models is provided, comprising the following steps:

[0053] Step S1: Recursively assemble the component trees of the two complex structures that need to be compared. During the recursion, calculate the average depth n of the tree according to the formula of the average path length to the leaf node.

[0054] Step S2: Based on the average depth n of the tree, divide the tree into four layers: A, B, C, and D. For layer A (the first n / 3-1 layers), construct spherical bounding boxes; for layer B (layers n / 3 to 2n / 3-1), construct AABB bounding boxes; for layer C (layers 2n / 3 to n-1), construct OBB bounding boxes; and for layer D (layer n and below), do not construct bounding boxes, directly traverse the nodes and call the CATIA CAA interference check interface. Specifically, if the average depth of the tree is 3, divide the tree into three layers: A, B, and C. For layer A (layer 1), construct spherical bounding boxes; for layer B (layer 2), construct AABB bounding boxes; and for layer C (layer 3 and below), do not construct bounding boxes, directly traverse the nodes and call the CATIA CAA interference check interface. If the average depth of the assembly tree does not exceed 2 and the maximum depth of the assembly tree does not exceed 3, directly traverse the nodes and call the interference check interface of CATIA CAA; if the average depth of the assembly tree does not exceed 2 and the maximum depth of the assembly tree exceeds 3, divide the assembly tree into three layers A, B, and C. For layer A (layer 1), an AABB bounding box needs to be constructed, and for layer B (layer 2 and below), no bounding box is constructed. Directly traverse the nodes and call the interference check interface of CATIA CAA.

[0055] Step S3: Calculate the spherical bounding box of the root node of the assembly tree of the two complex structural assemblies to be compared.

[0056] Step S4: Determine whether the spherical bounding boxes of the root nodes of the two complex structural assemblies intersect. If they do not intersect, end the process. If they intersect, proceed to step S5.

[0057] Step S5: Calculate the bounding boxes to be constructed corresponding to the lower-level nodes of the root nodes of the two complex structural assemblies, and determine whether they intersect pairwise. If they do not intersect, end the process. If they intersect, continue traversing the intersecting nodes and go to step S6.

[0058] Step S6: Calculate the bounding boxes that need to be constructed for the lower-level nodes of the corresponding intersecting nodes in the two complex structural assemblies S5, and determine whether they intersect. If they do not intersect, end the process; if they intersect, repeat step S6.

[0059] Furthermore, for step S1, the total cost formula for the quantitative evaluation index is established as Tcd = NpCp × NqCq. Tcd refers to the overall performance of the algorithm. Np refers to the time for bounding box connection detection. Cp refers to the cost of bounding box collision detection, Nq refers to the number of geometric object collision detections, and Cq refers to the cost of geometric object collision detection. Based on the average depth of the assembly tree and the complexity of the components, it is proposed to construct bounding boxes with different levels of tightness during collision detection to reduce the number of bounding box collision detections and the time for bounding box construction. This reduces the number of geometric object collision detections and the cost of geometric object collision detection, thus achieving efficient collision detection testing. However, these parameters are interdependent; therefore, reasonable values ​​of NpCpNqCq are calculated based on the average depth of the tree and the balance factor of the assembly tree structure.

[0060] Furthermore, for step S6, if the recursive traversal reaches the corresponding lower-level node that needs to be judged for interference at a level where a bounding box does not need to be constructed, there are three cases: 1) When both nodes are leaf nodes, perform interference check directly; 2) When either of the two nodes is a leaf node A, recursively traverse the other node B, find all the leaf nodes obtained from the traversal, and perform interference check with leaf node A; 3) When neither node is a leaf node, recursively traverse the two nodes A and B, find all the leaf nodes obtained from the traversal of node A, and perform interference check with all the leaf nodes obtained from the traversal of node B.

[0061] Furthermore, for step S6, if the recursive traversal reaches the corresponding lower-level node that needs to be judged for interference at the level where a bounding box needs to be constructed, but any node is a leaf node C, then an OBB bounding box is constructed for that leaf node, the bounding box of the other node is calculated, and it is determined whether they intersect. If they intersect, the node is recursively traversed, and the bounding box of the corresponding level is constructed synchronously. The intersection with leaf node C is then determined. This process continues until the recursion reaches the level where a bounding box does not need to be constructed. Then, the nodes that need to be compared at that level are recursively traversed, and all the leaf nodes obtained from the traversal are found to perform interference checks with leaf node C.

[0062] Figure 1 This is a schematic diagram of a traditional binary hierarchical bounding box tree provided for an embodiment of the present invention. Figure 1 As shown, the traditional binary hierarchical bounding box tree algorithm requires re-partitioning the space of the parts to generate a new tree structure. Although it has an advantage in efficiency, the overhead of considering the space partitioning and generating a new tree structure is obviously greater than the overhead of directly using the original assembly tree structure of the parts for fast and reasonable bounding box design.

[0063] Figure 2 is a schematic diagram of an assembly tree and a hierarchical bounding box model applicable to this invention, provided by an embodiment of the present invention. As shown in Figure 2(a), the assembly tree with a complex structure is a complex multi-way tree, and the traversal of the complex multi-way tree needs to consider the time complexity of the traversal. As shown in Figure 2(b), the complex multi-way tree is divided into corresponding bounding boxes by the partitioning algorithm of the hierarchical bounding box assembly tree.

[0064] Figure 3 This is a schematic diagram illustrating an example of a collision detection optimization algorithm based on a hierarchical bounding box assembly tree and synchronous recursive descent, provided as an embodiment of the present invention. Figure 3 As shown, the detection system using a hybrid hierarchical bounding box collision detection optimization algorithm structure significantly reduces the time required to quickly traverse and eliminate non-intersecting objects compared to the time required to recursively traverse each part leaf node. That is, the number of geometric object collision detections Nq and the consumption of geometric object collision detection Cq are reduced.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should be covered within the protection scope of the present invention.

Claims

1. A method for efficient interference checking of complex structural CAD models, employing a hierarchical bounding box assembly tree and a collision detection optimization algorithm with synchronous recursive descent, characterized in that... Includes the following steps: Step 1: Establish quantitative evaluation indicators; Recursively download the component assembly trees of the two complex structures that need to be compared. During the recursive download process, the average depth n of the tree is calculated based on the formula of the average path length to the leaf node. Step 2: Optimize the layered bounding box assembly tree algorithm. Specifically, based on the average depth n of the assembly tree, divide the assembly tree into four layers: A, B, C, and D. For layer A, a spherical bounding box needs to be constructed; for layer B, an AABB bounding box needs to be constructed; for layer C, an OBB bounding box needs to be constructed; and for layer D, no bounding box needs to be constructed. Instead, the nodes are directly traversed and the interference check interface of CATIA CAA is called. Here, layer A is the first n / 3-1 layers of the assembly tree, layer B is the n / 3 to 2n / 3-1 layers of the assembly tree, layer C is the 2n / 3 to n-1 layers of the assembly tree, and layer D is the nth layer and below of the assembly tree. Step 3: Recursively use the results of the optimized hierarchical bounding box assembly tree algorithm through the synchronous recursive descent algorithm.

2. The efficient interference inspection method for complex structural CAD models according to claim 1, characterized in that, Step 1 specifically involves: recursively downloading the component models of the two complex structures to be compared, establishing a total cost formula for quantitative evaluation indicators to measure the overall performance of the algorithm, and simultaneously calculating the average depth of the assembly tree during the recursive download process.

3. The efficient interference inspection method for complex structural CAD models according to claim 2, characterized in that, The total cost formula for the quantitative evaluation index is Tcd = NpCp × NqCq, where Tcd refers to the overall performance of the algorithm; Np refers to the time for bounding box connection detection; Cp refers to the cost of bounding box collision detection; Nq refers to the number of geometric object collision detections; and Cq refers to the cost of geometric object collision detection.

4. The efficient interference checking method for complex structural CAD models according to claim 3, characterized in that, For step 2, if the average depth of the assembly tree is 3, the assembly tree is divided into three layers: A, B, and C. A spherical bounding box needs to be built for layer A, an AABB bounding box needs to be built for layer B, and no bounding box needs to be built for layer C. The nodes are directly traversed and the interference check interface of CATIA CAA is called. At this time, layer A is the first layer of the assembly tree, layer B is the second layer of the assembly tree, and layer C is the third layer and below of the assembly tree.

5. The efficient interference checking method for complex structural CAD models according to claim 4, characterized in that, For step 2, if the average depth of the assembly tree does not exceed 2 and the maximum depth of the assembly tree does not exceed 3, directly traverse the nodes and call the interference check interface of CATIACAA; if the average depth of the assembly tree does not exceed 2 and the maximum depth of the assembly tree exceeds 3, divide the assembly tree into three layers A, B, and C. For layer A, an AABB bounding box needs to be constructed, and for layer B, no bounding box needs to be constructed. Directly traverse the nodes and call the interference check interface of CATIACAA. At this time, layer A is the first layer of the assembly tree, and layer B is the second layer and below of the assembly tree.

6. The efficient interference checking method for complex structural CAD models according to claim 5, characterized in that, Step 3 specifically includes: Step 3.1 Calculate the spherical bounding box of the root node of the assembly tree of the two complex structural assemblies to be compared; Step 3.2: Determine whether the spherical bounding boxes of the root nodes of the two complex structural assemblies intersect. If they intersect, proceed to step 3.3; otherwise, the process ends. Step 3.3: Optimize the results using the hierarchical bounding box assembly tree algorithm. By traversing the nodes layer by layer through the synchronous descent rule, the corresponding bounding boxes are calculated synchronously level by level, and the intersection status of the child nodes is detected.

7. The efficient interference inspection method for complex structural CAD models according to claim 6, characterized in that, In step 3.3, if the recursive traversal reaches a lower-level node that needs to be judged for interference at a level where a bounding box does not need to be constructed, there are three cases: 1) When both nodes are leaf nodes, perform interference check directly; 2) When either node is a leaf node A, recursively traverse the other node B, find all leaf nodes obtained from the traversal, and perform interference check with leaf node A; 3) When neither node is a leaf node, recursively traverse both nodes A and B, find all leaf nodes obtained from the traversal of node A, and perform interference check with all leaf nodes obtained from the traversal of node B. If the recursive traversal reaches a lower-level node that needs to be judged for interference at a level where a bounding box needs to be built, but any node is a leaf node C, then construct an OBB bounding box for that leaf node, calculate the bounding box of the other node, and determine whether they intersect. If they intersect, recursively traverse that node, simultaneously construct the bounding box of the corresponding level, and determine whether it intersects with leaf node C, until the recursion reaches a level where no bounding box needs to be built. Then, recursively traverse the nodes that need to be compared at that level, find all the leaf nodes obtained from the traversal, and perform interference checks with leaf node C.

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