Method and system for bolt removal detection in a fixture design

Abstract

The present application provides a kind of method and system for detecting bolt dismounting in fixture design, comprising: selecting fixture numerical model file to import in software;After importing, bolt identification operation is carried out, and all bolt information in numerical model is identified;According to bolt information and equipment specification in equipment library, preliminary selection of assembly equipment is carried out, and whether interference exists is judged;After detection is completed, the position of bolt is cut out, and is labeled and exported by YOLO model.The present application uses software operation, and can more quickly and efficiently complete bolt dismounting detection through the detection of set logic, greatly reduces the requirement for professional technology, saves labor cost and time cost.

Description

Technical Field

[0001] This invention belongs to the field of automotive automation design, and in particular relates to a method and system for detecting bolt disassembly in fixture design. Background Technology

[0002] In the field of automotive automation design, the most crucial operation after fixture design is the verification of the mounting bolts. Fixtures may require frequent disassembly during use (e.g., replacing worn parts, adjusting positioning elements). Insufficient space around the bolts can prevent assembly equipment (disassembly tools) from operating properly, prolonging maintenance time or even preventing complete disassembly. For example, socket wrenches require a certain height, open-end wrenches require sufficient rotation angle, and electric disassembly tools require additional operating margin. Obstacles around the bolt head or nut (such as the fixture body or other parts) may block the tool path. Properly allocating space prevents tools from colliding with surrounding structures and reduces operational errors.

[0003] Currently, bolt disassembly testing in fixture design is typically done manually. This includes manually selecting assembly equipment, assembling the equipment, and checking the disassembly space. Manual measurement is also sometimes necessary. Because each bolt is in a different location, this process needs to be performed on every single bolt. Afterwards, screenshots of any bolts that don't meet the requirements need to be taken and documented manually. This overall manual process is time-consuming and inaccurate, potentially leading to errors due to insufficient personal experience. Summary of the Invention

[0004] This invention proposes a method and system for detecting bolt disassembly in fixture design. It uses software operation and performs detection through set logic, which can complete the bolt disassembly detection more quickly and efficiently, greatly reducing the requirements for professional technology and saving labor and time costs.

[0005] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0006] A method for testing the disassemblyability of bolts in fixture design, comprising:

[0007] S1. Select the fixture model file and import it into the software; after importing, perform bolt recognition to identify all bolt information in the model.

[0008] S2. Based on bolt information and equipment specifications in the equipment library, conduct an initial selection of assembly equipment;

[0009] S3. If the assembly equipment is an internal hex wrench, check whether there is axial interference when the long end and short end of the internal hex wrench are used to remove the bolt, and whether there is enough space to unscrew it in the axial direction.

[0010] If the assembly equipment is a socket wrench, check the interference between the socket and the fixture, and determine whether there is any interference between the socket and other standard parts;

[0011] If the assembly equipment is another type of wrench, determine whether there is interference by generating the minimum bounding box contour;

[0012] S4. After the inspection is completed, take a screenshot of the corresponding position of the bolt, annotate it using the YOLO model and output it.

[0013] Furthermore, the method for bolt identification in step S1 includes:

[0014] S101. For the national standard number and manufacturer's standard number of bolts, first set up the equipment library, set the part number of the standard bolt parts as a configuration item, and the software will traverse the internal bolt number in all the input data and finally record the bolt position information.

[0015] S102. For cases where bolts are stored in the same standard assembly, the software first identifies the location of the standard file by an identifier, then iterates through the required bolt models, and finally records the bolt location information.

[0016] S103. For situations where bolts are stored in different locations, the software identifies bolts by comparing the dimensions of the geometric model in the fixture CAD file with the dimensions of the bolt standard part model, and records the relevant model and location information.

[0017] S104. For bolts that are in the form of sheet bodies or envelope bodies, the software traverses the fixture model files for a full search. If models that are both sheet bodies and solids with the same specifications are found, the solid model is preferred. If no solid model is found, the sheet body file is preferred, identified as a bolt, and the relevant model and location information are recorded.

[0018] S105. If none of the above methods can be used to identify the bolt, manually select the bolt model. The software will then identify the bolt parameter information. Any information that cannot be identified will be added manually.

[0019] Furthermore, the detection method for assembling an internal hex wrench in step S3 specifically includes:

[0020] S301. Identify the size of the bolt's internal hexagonal head end. Take the intersection of the bolt axis and the end face as the center point, and the maximum distance from the internal hexagonal head as the radius. Take the sum of the length of the long end of the internal hexagonal wrench, the safety distance, and the bolt length as height one, and construct cylinder one along the negative direction of bolt installation. Take the sum of the length of the short end of the internal hexagonal wrench, the safety distance, and the bolt length as height two, and construct cylinder two along the negative direction of bolt installation.

[0021] S302. Perform interference detection between cylinder one and cylinder two and the fixture respectively. The default detection type is "contact + collision". If both cylinder one corresponding to the long end and cylinder two corresponding to the short end interfere with the fixture, the hex wrench will not be selected and the detection will be stopped. If neither cylinder one corresponding to the long end nor cylinder two corresponding to the short end interferes with the fixture, proceed to step S303. If one end of cylinder one corresponding to the long end or cylinder two corresponding to the short end does not interfere with the fixture, proceed to step S304.

[0022] S303. Identify the size of the bolt's internal hexagonal end. Using the intersection of the bolt axis and the end face as the starting point, along the negative direction of bolt installation, first, use the length of the long end of the internal hexagonal wrench as the distance to make the center point, and use the length of the short end of the internal hexagonal wrench as the radius to make surface one; then, use the sum of the length of the long end of the internal hexagonal wrench and the bolt length as the distance to make the center point, and use the length of the short end of the internal hexagonal wrench as the radius to make surface two. Surface one and surface two are used as the standard surfaces of the detection space. Execute step S305.

[0023] First, use the short end of the Allen wrench as the distance to make the center point, and use the long end of the Allen wrench as the radius to make surface three; then, use the sum of the short end of the Allen wrench and the bolt length as the distance to make the center point, and use the long end of the Allen wrench as the radius to make surface four. Surface three and surface four are used as the standard surfaces of the inspection space. Then, execute step S305.

[0024] S304. Identify the internal hexagonal end size of the bolt. Taking the intersection of the bolt axis and the end face as the starting point, along the negative direction of bolt installation, first use the length of the non-interfering end as the distance to make the center point, and use the length of the other end as the radius to make surface one; then use the sum of the length of this end and the bolt length as the distance to make the center point, and use the length of the other end as the radius to make surface two. Surface one and surface two are used as the standard surfaces of the detection space. Execute step S305.

[0025] S305. Surface 1 and Surface 2, which serve as the standard surfaces of the testing space, are subjected to interference testing with the fixture to determine whether the sector angle value of the non-interference range meets the testing standard value. If it does, the disassembly test is qualified.

[0026] Furthermore, the detection method for assembling a socket wrench in step S3 specifically includes:

[0027] Using the sum of the socket radius and the safety distance of the socket wrench as the radius, and the sum of the socket length and the extension rod length as the height, construct a cylinder I along the extension rod direction. Using the intersection of the extension rod and the handle as the center point, construct a plane I with the longest distance from the intersection of the extension rod and the handle to both ends of the handle as the radius. Check the interference relationship between cylinder I and the fixture, then check the interference relationship between cylinder I and other bolts, then check the interference relationship between plane I and the fixture, then check the interference relationship between plane I and other bolts. If there is no interference, the disassembly test is qualified.

[0028] Furthermore, the detection method for assembling other wrenches in step S3 specifically includes:

[0029] Assemble the assembly equipment to the bolt position and generate a minimum bounding box profile one with the installation end of the assembly equipment as the size reference. Generate a minimum bounding box profile two with the axial dimension of the minimum bounding box profile one plus the bolt length as the size reference. Determine whether there is any interference between the minimum bounding box profile two and the fixture. If there is no interference, the disassembly test is qualified.

[0030] In another aspect, the present invention also proposes a system for detecting the disassemblyability of bolts in fixture design, comprising:

[0031] Import and Recognition Module: Select the fixture model file and import it into the software; after importing, perform bolt recognition to identify all bolt information within the model;

[0032] Preliminary selection module: Performs preliminary selection of assembly equipment based on bolt information and equipment specifications in the equipment library;

[0033] Testing module: If the assembly equipment is an Allen wrench, test whether there is axial interference when the long end and short end of the Allen wrench remove the bolt, and whether there is enough space to unscrew it in the axial direction.

[0034] If the assembly equipment is a socket wrench, check the interference between the socket and the fixture, and determine whether there is any interference between the socket and other standard parts;

[0035] If the assembly equipment is another type of wrench, determine whether there is interference by generating the minimum bounding box contour;

[0036] Output module: After the detection is completed, take a screenshot of the corresponding position of the bolt, annotate it using the YOLO model and output it.

[0037] Furthermore, the import recognition module includes:

[0038] First identification unit: For the national standard number and manufacturer's standard number of the bolt, the equipment library is set first, and the part number of the standard bolt is configured. The software traverses the internal bolt number in all the input data and finally records the bolt position information.

[0039] Second identification unit: When bolts are stored in the same standard assembly, the software first identifies the location of the standard file through an identifier, then iterates through the required bolt models, and finally confirms the bolt location information;

[0040] The third identification unit: When bolts are stored in different locations, the software identifies the bolts by comparing the dimensions of the geometric model in the fixture CAD file with the dimensions of the standard bolt model, and records the relevant model and location information.

[0041] Fourth identification unit: For bolts in the form of sheet bodies or envelope bodies, the software traverses the fixture model files for a full search. If models that are both sheet bodies and solids with the same specifications are found, the solid model is preferred. If no solid model is found, the sheet body file is preferred, and the bolt is identified as a bolt. The relevant model and location information are recorded.

[0042] Fifth identification unit: For cases where none of the above can be identified, manually select the bolt model, and the software will identify the bolt parameter information. Any information that cannot be identified will be added manually.

[0043] Furthermore, the detection module includes an internal hex wrench detection submodule, comprising:

[0044] Cylindrical Unit: Identify the size of the bolt's internal hexagonal end, take the intersection of the bolt axis and the end face as the center point, and the maximum distance from the internal hexagonal as the radius; take the sum of the long end length of the internal hexagonal wrench, the safety distance, and the bolt length as height one, and construct cylinder one along the negative direction of bolt installation; take the sum of the short end length of the internal hexagonal wrench, the safety distance, and the bolt length as height two, and construct cylinder two along the negative direction of bolt installation;

[0045] First Interference Detection Unit: Interference detection is performed between cylinder one and cylinder two and the fixture, with the default detection type being "contact + collision". If both cylinder one (long end) and cylinder two (short end) interfere with the fixture, the hex wrench is not selected and the detection is stopped. If neither cylinder one (long end) nor cylinder two (short end) interferes with the fixture, the process moves to the first standard surface unit. If one end of either cylinder one (long end) or cylinder two (short end) does not interfere with the fixture, the process moves to the second standard surface unit.

[0046] First standard surface unit: Identify the size of the bolt's internal hexagonal end. Taking the intersection of the bolt axis and the end face as the starting point, along the negative direction of bolt installation, first, use the length of the long end of the internal hexagonal wrench as the distance to make the center point, and use the length of the short end of the internal hexagonal wrench as the radius to make surface one; then, use the sum of the length of the long end of the internal hexagonal wrench and the bolt length as the distance to make the center point, and use the length of the short end of the internal hexagonal wrench as the radius to make surface two. Surface one and surface two serve as the standard surface of the detection space, and the second interference detection unit is executed.

[0047] First, take the short end of the Allen wrench as the distance to the center point, and take the long end of the Allen wrench as the radius to make surface three; then take the sum of the short end of the Allen wrench and the bolt length as the distance to the center point, and take the long end of the Allen wrench as the radius to make surface four. Surface three and surface four are used as the standard surfaces of the detection space, and the second interference detection unit is executed.

[0048] The second standard surface unit: after identifying the size of the bolt's internal hexagonal end, taking the intersection of the bolt axis and the end face as the starting point, along the negative direction of bolt installation, firstly, using the length of the non-interfering end as the distance to the center point, and using the length of the other end as the radius to create surface one; then, using the sum of the length of this end and the bolt length as the distance to the center point, and using the length of the other end as the radius to create surface two. Surface one and surface two serve as the standard surface of the detection space, and the second interference detection unit is executed.

[0049] The second interference detection unit: Surface 1 and Surface 2, which serve as the standard surfaces of the detection space, are subjected to interference detection with the fixture to determine whether the sector angle value of the non-interference range can meet the detection standard value. If it can, the disassembly test is qualified.

[0050] Furthermore, the detection module includes a socket wrench detection submodule, comprising:

[0051] Using the sum of the socket radius and the safety distance of the socket wrench as the radius, and the sum of the socket length and the extension rod length as the height, construct a cylinder I along the extension rod direction. Using the intersection of the extension rod and the handle as the center point, construct a plane I with the longest distance from the intersection of the extension rod and the handle to both ends of the handle as the radius. Check the interference relationship between cylinder I and the fixture, then check the interference relationship between cylinder I and other bolts, then check the interference relationship between plane I and the fixture, then check the interference relationship between plane I and other bolts. If there is no interference, the disassembly test is qualified.

[0052] Furthermore, the detection module includes other wrench detection sub-modules, including:

[0053] Assemble the assembly equipment to the bolt position and generate a minimum bounding box profile one with the installation end of the assembly equipment as the size reference. Generate a minimum bounding box profile two with the axial dimension of the minimum bounding box profile one plus the bolt length as the size reference. Determine whether there is any interference between the minimum bounding box profile two and the fixture. If there is no interference, the disassembly test is qualified.

[0054] Compared with the prior art, the present invention has the following beneficial effects:

[0055] 1. This invention provides a logic for software-based bolt disassembly detection. By using software judgment and recognition, the steps of manual bolt disassembly spatial detection are simplified to software operation. After inputting the corresponding logical rules, the detection is more efficient and accurate, reducing the need for professional expertise and saving time and personnel costs.

[0056] 2. Based on the software approach of this invention, with the continuous optimization and iteration of the algorithm, subsequent detection and judgment will become increasingly intelligent, and the overall judgment data can be customized and modified, providing a reference sample for further software development based on deep learning intelligent design. Attached Figure Description

[0057] Figure 1 This is a flowchart illustrating Embodiment 1 of the present invention;

[0058] Figure 2 This is a diagram of the main software interface of Embodiment 1 of the present invention;

[0059] Figure 3 This is an identification diagram of the bolts in Embodiment 1 of the present invention stored in the same standard assembly;

[0060] Figure 4 This is an identification diagram of the bolt form as a solid in Embodiment 1 of the present invention;

[0061] Figure 5 This is an identification diagram of the bolt type as a sheet body in Embodiment 1 of the present invention;

[0062] Figure 6 This is a schematic diagram of the internal hex wrench structure of Embodiment 1 of the present invention, wherein 1 is the long end and 2 is the short end;

[0063] Figure 7 This is a schematic diagram of the cylinder formed by the long end of the internal hex wrench in Embodiment 1 of the present invention;

[0064] Figure 8 This is a schematic diagram of the short end of the internal hex wrench generating a second cylinder in Embodiment 1 of the present invention;

[0065] Figure 9 This is a schematic diagram of surface one of the standard surface of the detection space in Embodiment 1 of the present invention;

[0066] Figure 10 This is a schematic diagram of the sector-shaped surface detection in Embodiment 1 of the present invention;

[0067] Figure 11 This is a schematic diagram of the socket wrench structure according to Embodiment 1 of the present invention, wherein 3 is the socket, 4 is the connecting rod, 5 is the handle, a is the radius of the socket, b is the sum of the lengths of the socket and the connecting rod, and r is the longest distance from the intersection of the connecting rod and the handle to both ends of the handle;

[0068] Figure 12 This is a schematic diagram of the minimum bounding box outline of Embodiment 1 of the present invention;

[0069] Figure 13 This is a schematic diagram of the minimum bounding box outline of Embodiment 1 of the present invention;

[0070] Figure 14 This is a schematic diagram of the system structure of Embodiment 2 of the present invention. Detailed Implementation

[0071] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0072] To make the purpose and features of this invention patent clearer and easier to understand, the specific embodiments of this invention patent will be further described below with reference to the accompanying drawings.

[0073] Example 1:

[0074] The method for testing the disassemblyability of bolts in fixture design proposed in this embodiment is as follows: Figure 1 As shown, it includes:

[0075] S1. Select the fixture model file and import it into the software; after importing, perform bolt recognition to identify all bolt information in the model.

[0076] In the fixture design of this invention, the bolt disassembly test is implemented through software. Therefore, it is required that the fixture digit model file can be selected for import in the software interface, and the digit model of the bolt can be identified from the digit model file.

[0077] like Figure 2 The image shows the main interface of the software. Clicking "Select Product Node" on the main interface causes the software to call a 3D design software via API functions to read the digital model file. In this embodiment, the 3D design software uses CATIA, reading the model under the SM node of CATIA, which is then available for the user to select. After selection, the model is displayed in the display box.

[0078] After importing the digital model file, the software accurately identifies bolts of different types and with different identification marks for different scenarios, obtaining their precise locations and related information. Selecting "Bolt Recognition" on the main interface allows the software to recognize the input digital model and identify all bolt information (specifications, names, locations, etc.) within it, recording the relevant information.

[0079] For bolts with both national and manufacturer designations (including those coexisting within the same digital model), the equipment library is first set up, and the part numbers of the standard bolt parts are configured. The software then iterates through all the input data to record the internal stud designations and finally records the bolt position information.

[0080] For bolts stored within the same standard assembly (GB): such as Figure 3 As shown, the standard file location is first identified by an identifier, then the required bolt numbers are traversed, and finally the bolt location and other information are confirmed and recorded.

[0081] For situations where bolts are stored in different locations (outsourced) and bolts are identified based on their serial numbers: bolt identification is performed through intelligent judgment using geometric models. By comparing the shape with the dimensions of the standard bolt part model, the relevant model and location information are recorded.

[0082] For bolts that are either sheet bodies or envelope bodies (solids): During the software's traversal, a full search is performed. If models that are both sheet bodies and solids with the same specifications are found, the solid model is selected first. Figure 4 As shown; if there is no entity, such as Figure 5 As shown, the preferred file is the sheet metal file, which records and saves the bolt information.

[0083] In special cases, if the input bolt cannot be identified and detected in the above scenarios, the software supports manual selection of the bolt. Click "Manual Selection of Nodes" to manually select the bolt model through the CATIA interface. The software will identify the bolt parameter information. Parts that cannot be automatically identified (such as bolt size) need to be added manually.

[0084] S2. Based on bolt information and equipment specifications in the equipment library, conduct an initial selection of assembly equipment;

[0085] On the main interface, click "Preliminary Selection of Assembly Equipment" to enter the preliminary selection module. Select the assembly equipment used to assemble the bolts, such as hex wrenches, socket wrenches, box wrenches, adjustable wrenches, torque wrenches, etc. First, perform preliminary selection of equipment based on bolt information and equipment specifications in the equipment library. Then, output the preliminary selection of assembly equipment and proceed to the next step S3. Based on the location of the bolt, bolt specifications, and spatial conditions, perform bolt assembly simulation verification to detect bolt disassembly.

[0086] S3. If the assembly equipment is an internal hex wrench, check whether there is axial interference when removing the bolt from the long and short ends of the internal hex wrench, and whether there is enough space to unscrew it in the axial direction. If the assembly equipment is a socket wrench, check the interference between the socket and the fixture, and determine whether there is interference between the socket and other standard parts. If the assembly equipment is another type of wrench, determine whether there is interference by generating the minimum bounding box contour.

[0087] Specifically, the testing methods used in this step vary depending on the assembly equipment initially selected in step S2.

[0088] 1. When using an Allen wrench for assembly, check for axial interference when removing the bolts to ensure sufficient axial space for unscrewing. For example... Figure 6 As shown, both the long end 1 and the short end 2 of the Allen wrench are inspected.

[0089] Let the length of the long end 1 of the Allen wrench be a, and the length of the short end 2 be b.

[0090] (1) Identify the size of the bolt's internal hexagonal head end. Using the intersection of the bolt axis and the end face as the center point, and the maximum distance from the center point to the internal hexagonal head as the radius, for the case where the bolt is assembled using the long end 1 of an internal hexagonal wrench, use the sum of a + safety distance + bolt length as the height 1. Construct a cylinder 1 along the negative direction of bolt installation, such as... Figure 7 As shown. For the case where the short end 2 of an Allen wrench is used to assemble the bolt, the height 2 is calculated as the sum of b + safety distance + bolt length. A cylinder 2 is constructed along the negative direction of bolt installation, as follows: Figure 8 As shown.

[0091] The safe distance refers to the safe operating distance. In this embodiment, 5mm is taken as the safe operating distance, which can be changed according to the actual situation.

[0092] (2) Then, cylinder one and cylinder two are respectively subjected to interference detection with the fixture. The default detection type is "contact + collision" and "between two selections". Selection 1 is the fixture digital model, and selection 2 is cylinder one or cylinder two. The gap value of selection 1 and selection 2 is detected. If the gap value is <0mm, the two are in a collision relationship. If the gap value is =0mm, the two are in a contact relationship. Both collision relationship and contact relationship are classified as interference relationship.

[0093] (3) After the axial detection is completed, record the interference between the long end a and the short end b. If both ends interfere, it will not be selected. If one end interferes and the other end is normal, record the non-interfering end. In the next space simulation process, only the non-interfering end will be detected. If neither end interferes, both ends will be detected in the next space simulation process.

[0094] (4) For those that do not interfere with each other at both ends, perform tests at both ends. The first test process includes: identifying the size of the hexagonal end of the bolt, taking the intersection of the bolt axis and the end face as the starting point, and along the negative direction of bolt installation, firstly, take the long end length a as the center point and the short end length b as the radius to make surface one; then take a + the sum of the bolt lengths as the center point and the short end length b as the radius to make surface two. Surface one and surface two are used as the standard planes of the test space. Interference tests are performed with the fixture through the standard planes to determine whether the sector angle value of the non-interference range can meet the test standard value. If it can, the disassembly test is qualified.

[0095] The second inspection process includes: identifying the internal hexagonal head dimensions of the bolt; using the intersection of the bolt axis and the end face as the starting point; and along the negative direction of bolt installation, firstly, using the short end length *b* as the center point and the long end length *a* as the radius to create surface three; then, using the sum of *b* and the bolt length as the center point and the long end length *a* as the radius to create surface four. Surfaces three and four serve as the standard planes of the inspection space. Figure 9The figure shows a schematic diagram of surface 1 of the standard surface. By performing interference detection between the standard surface and the fixture respectively, it is judged whether the sector angle value of the non-interference range can meet the detection standard value. If it meets, the disassembly detection is qualified.

[0096] (5) For the case where only one end interferes and the other end is normal, for example, the short end does not interfere and the long end interferes. Similarly, taking the intersection point of the bolt axis and the end face as the starting point, along the negative direction of the bolt installation, taking b as the distance to make the center point, taking a as the radius, making surface 1, taking the sum of b + bolt length as the distance to make the center point, taking a as the radius, making surface 2. Surface 1 and surface 2 are used as the standard surfaces of the detection space. By performing interference detection between the standard surface and the fixture respectively, it is judged whether the sector angle value of the non-interference range can meet the detection standard value. If it meets, the disassembly detection is qualified.

[0097] The process of performing interference detection between the standard surface and the fixture respectively in the above steps includes:

[0098] As Figure 10 shown, perform interference detection between the standard surface and the fixture, judge the intersection position of the standard surface and the fixture and generate an intersection point. Connect the intersection point with the axis center point, and finally judge the relationship between the sector surface angle (i.e., the sector angle of the non-interference range) formed between the connection lines that does not include the fixture structure and the judgment standard. In this embodiment, the judgment standard is set to 60°. If it is greater than or equal to 60°, the disassembly detection is qualified. The judgment standard can be changed from the background according to actual needs.

[0099] 2. When the assembly equipment is a socket wrench, the detection method includes:

[0100] As Figure 11 shown is a schematic diagram of the structure of a socket wrench. The structure of the socket wrench usually includes a socket 3, an extension rod 4, and a handle 5. Let a be the radius of the socket 3, b be the sum of the lengths of the socket 3 and the extension rod 4, and r be the longest distance from the intersection point of the extension rod 4 and the handle 5 to both ends of the handle 5. Taking the sum of a + safety distance as the radius and b as the height, make a cylinder 1 along the direction of the extension rod 4. Taking the intersection point of the extension rod 4 and the handle 5 as the center point, make a plane 1 with a radius of r; detect the interference relationship between the cylinder 1 and the fixture, then detect the interference relationship between the cylinder 1 and each other bolt, then detect the interference relationship between the plane 1 and the fixture, and then detect the interference relationship between the plane 1 and each other bolt. If there is no interference, the disassembly detection is qualified.

[0101] 3. When the assembly equipment is other wrenches, such as a hex key wrench, a torque wrench, etc., the detection method includes:

[0102] Assemble the assembly equipment to the bolt position, generate a minimum bounding box (Minimum Bounding Box) contour 1 with the installation end of the assembly equipment as the dimension reference, as Figure 12As shown. Then, using the axial dimension of minimum bounding box contour one plus the bolt length as a dimensional reference, minimum bounding box contour two is generated, as shown. Figure 13 As shown. Determine whether there is interference between the minimum bounding box contour 2 and the fixture (i.e., perform interference detection, the detection method is the same as the interference detection method described above); if there is no interference, the disassembly test is qualified.

[0103] The method for generating the minimum bounding box contour is to call CATIA commands, obtain the part's principal axis of inertia, transform the part's coordinates, calculate the bounding box, reverse the coordinates, and output the bounding box to finally obtain the minimum bounding box contour.

[0104] S4. After the inspection is completed, take a screenshot of the corresponding position of the bolt, annotate it using the YOLO model and output it.

[0105] In this step, after all bolts have been inspected, the inspected information is entered into a table on the main interface for easy viewing. For example... Figure 2 As shown, the "Remarks" column of the table displays screenshots of key locations via links.

[0106] The screenshot can be used by the YOLO model to identify and label the part attributes of all specific areas. YOLO divides the input image into an S×S grid (e.g., 13×13), and each grid is responsible for predicting the target whose center point falls within its area. Each grid generates B bounding boxes (B is usually 2-3), and each box contains 5 core parameters: center coordinates (x, y), width w, height h, confidence score, and class.

[0107] The formula for the center coordinates is: ; ;

[0108] Where t x and t y The center coordinate offset is determined by the Sigmoid function. The constraint is in the range [0,1], c x and c y It is the coordinate of the top left corner of the grid.

[0109] The formulas for width w and height h are: ; ;

[0110] Where tw and th represent the width and height scaling ratios, respectively: width and height based on the preset bounding box (Anchor Box). and Exponential scaling: This design enables the model to adaptively adjust the bounding box shape, improving its adaptability to different target sizes.

[0111] The software automatically sets the range value and performs screenshot operations within the area. The output location can be customized by the user, and the export format can also be changed when selecting the standard.

[0112] This embodiment provides the logic for software to perform bolt disassembly testing. By using software judgment and recognition, the steps of manually performing bolt disassembly testing are simplified to software operation. After inputting the corresponding logical rules, the testing is more efficient and accurate, reducing the need for professional expertise and saving time and personnel costs.

[0113] Example 2:

[0114] This embodiment proposes a system for detecting the disassemblyability of bolts in fixture design, such as... Figure 14 As shown, it includes:

[0115] Import and Recognition Module: Select the fixture model file and import it into the software; after importing, perform bolt recognition to identify all bolt information within the model;

[0116] Preliminary selection module: Performs preliminary selection of assembly equipment based on bolt information and equipment specifications in the equipment library;

[0117] Testing module: If the assembly equipment is an Allen wrench, test whether there is axial interference when the long end and short end of the Allen wrench remove the bolt, and whether there is enough space to unscrew it in the axial direction.

[0118] If the assembly equipment is a socket wrench, check the interference between the socket and the fixture, and determine whether there is any interference between the socket and other standard parts;

[0119] If the assembly equipment is another type of wrench, determine whether there is interference by generating the minimum bounding box contour;

[0120] Output module: After the detection is completed, take a screenshot of the corresponding position of the bolt, annotate it using the YOLO model and output it.

[0121] The import recognition module includes:

[0122] First identification unit: For the national standard number and manufacturer's standard number of the bolt, the equipment library is set first, and the part number of the standard bolt is configured. The software traverses the internal bolt number in all the input data and finally records the bolt position information.

[0123] Second identification unit: When bolts are stored in the same standard assembly, the software first identifies the location of the standard file through an identifier, then iterates through the required bolt models, and finally confirms the bolt location information;

[0124] The third identification unit: When bolts are stored in different locations, the software identifies the bolts by comparing the dimensions of the geometric model in the fixture CAD file with the dimensions of the standard bolt model, and records the relevant model and location information.

[0125] Fourth identification unit: For bolts in the form of sheet bodies or envelope bodies, the software traverses the fixture model files for a full search. If models that are both sheet bodies and solids with the same specifications are found, the solid model is preferred. If no solid model is found, the sheet body file is preferred, and the bolt is identified as a bolt. The relevant model and location information are recorded.

[0126] Fifth identification unit: For cases where none of the above can be identified, manually select the bolt model, and the software will identify the bolt parameter information. Any information that cannot be identified will be added manually.

[0127] The testing module includes an internal hex wrench testing submodule, which includes:

[0128] Cylindrical Unit: Identify the size of the bolt's internal hexagonal end, take the intersection of the bolt axis and the end face as the center point, and the maximum distance from the internal hexagonal as the radius; take the sum of the long end length of the internal hexagonal wrench, the safety distance, and the bolt length as height one, and construct cylinder one along the negative direction of bolt installation; take the sum of the short end length of the internal hexagonal wrench, the safety distance, and the bolt length as height two, and construct cylinder two along the negative direction of bolt installation;

[0129] First Interference Detection Unit: Interference detection is performed between cylinder one and cylinder two and the fixture, with the default detection type being "contact + collision". If both cylinder one (long end) and cylinder two (short end) interfere with the fixture, the hex wrench is not selected and the detection is stopped. If neither cylinder one (long end) nor cylinder two (short end) interferes with the fixture, the process moves to the first standard surface unit. If one end of either cylinder one (long end) or cylinder two (short end) does not interfere with the fixture, the process moves to the second standard surface unit.

[0130] First standard surface unit: Identify the size of the bolt's internal hexagonal end. Taking the intersection of the bolt axis and the end face as the starting point, along the negative direction of bolt installation, first, use the length of the long end of the internal hexagonal wrench as the distance to make the center point, and use the length of the short end of the internal hexagonal wrench as the radius to make surface one; then, use the sum of the length of the long end of the internal hexagonal wrench and the bolt length as the distance to make the center point, and use the length of the short end of the internal hexagonal wrench as the radius to make surface two. Surface one and surface two serve as the standard surface of the detection space, and the second interference detection unit is executed.

[0131] First, take the short end of the Allen wrench as the distance to the center point, and take the long end of the Allen wrench as the radius to make surface three; then take the sum of the short end of the Allen wrench and the bolt length as the distance to the center point, and take the long end of the Allen wrench as the radius to make surface four. Surface three and surface four are used as the standard surfaces of the detection space, and the second interference detection unit is executed.

[0132] The second standard surface unit: after identifying the size of the bolt's internal hexagonal end, taking the intersection of the bolt axis and the end face as the starting point, along the negative direction of bolt installation, firstly, using the length of the non-interfering end as the distance to the center point, and using the length of the other end as the radius to create surface one; then, using the sum of the length of this end and the bolt length as the distance to the center point, and using the length of the other end as the radius to create surface two. Surface one and surface two serve as the standard surface of the detection space, and the second interference detection unit is executed.

[0133] The second interference detection unit: Surface 1 and Surface 2, which serve as the standard surfaces of the detection space, are subjected to interference detection with the fixture to determine whether the sector angle value of the non-interference range can meet the detection standard value. If it can, the disassembly test is qualified.

[0134] The detection module includes a socket wrench detection submodule, which includes:

[0135] Using the sum of the socket radius and the safety distance of the socket wrench as the radius, and the sum of the socket length and the extension rod length as the height, construct a cylinder I along the extension rod direction. Using the intersection of the extension rod and the handle as the center point, construct a plane I with the longest distance from the intersection of the extension rod and the handle to both ends of the handle as the radius. Check the interference relationship between cylinder I and the fixture, then check the interference relationship between cylinder I and other bolts, then check the interference relationship between plane I and the fixture, then check the interference relationship between plane I and other bolts. If there is no interference, the disassembly test is qualified.

[0136] The detection module includes other wrench detection sub-modules, including:

[0137] Assemble the assembly equipment to the bolt position and generate a minimum bounding box profile one with the installation end of the assembly equipment as the size reference. Generate a minimum bounding box profile two with the axial dimension of the minimum bounding box profile one plus the bolt length as the size reference. Determine whether there is any interference between the minimum bounding box profile two and the fixture. If there is no interference, the disassembly test is qualified.

[0138] The system for detecting bolt disassembly in fixture design proposed in this embodiment can realize the method for detecting bolt disassembly in fixture design described in Embodiment 1, and has the same technical effect as Embodiment 1.

[0139] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for testing the disassemblyability of bolts in fixture design, characterized in that, include: S1. Select the fixture model file and import it into the software; After importing, perform bolt recognition to identify all bolt information within the digital model; S2. Based on bolt information and equipment specifications in the equipment library, conduct an initial selection of assembly equipment; assembly equipment includes hex wrenches, socket wrenches, and other wrenches; S3. If the assembly equipment is an internal hex wrench, check whether there is axial interference when the long end and short end of the internal hex wrench are used to remove the bolt, and whether there is enough space to unscrew it in the axial direction. If the assembly equipment is a socket wrench, check the interference between the socket and the fixture, and determine whether the socket interferes with other standard parts. This includes: using the sum of the socket radius and the safety distance as the radius, and the sum of the socket length and the extension rod length as the height, draw a cylinder along the extension rod direction. Use the intersection of the extension rod and the handle as the center point, and the longest distance from the intersection of the extension rod and the handle to both ends of the handle as the radius to draw a plane. Check the interference between cylinder one and the fixture, then check the interference between cylinder one and other bolts, then check the interference between plane one and the fixture, and then check the interference between plane one and other bolts. If there is no interference, the disassembly test is qualified. If the assembly equipment is a different type of wrench, determine whether there is interference by generating the minimum bounding box contour; S4. After the inspection is completed, take a screenshot of the corresponding position of the bolt, annotate it using the YOLO model and output it.

2. The method for detecting bolt disassemblyability in fixture design according to claim 1, characterized in that, The method for bolt identification in step S1 includes: S101. For the national standard number and manufacturer's standard number of bolts, first set up the equipment library, set the part number of the standard bolt parts as a configuration item, and the software will traverse the internal bolt number in all the input data and finally record the bolt position information. S102. For cases where bolts are stored in the same standard assembly, the software first identifies the location of the standard file by an identifier, then iterates through the required bolt models, and finally records the bolt location information. S103. For situations where bolts are stored in different locations, the software identifies bolts by comparing the dimensions of the geometric model in the fixture CAD file with the dimensions of the bolt standard part model, and records the relevant model and location information. S104. For bolts that are in the form of sheet bodies or envelope bodies, the software traverses the fixture model files for a full search. If models that are both sheet bodies and solids with the same specifications are found, the solid model is preferred. If no solid model is found, the sheet body file is preferred, identified as a bolt, and the relevant model and location information are recorded. S105. If the above methods fail to identify the bolt, manually select the bolt model. The software will then identify the bolt parameter information. Any information that cannot be identified will be added manually.

3. The method for testing the disassemblyability of bolts in fixture design according to claim 1, characterized in that, The specific testing method for assembling an internal hex wrench in step S3 includes: S301. Identify the size of the bolt's internal hexagonal head end. Take the intersection of the bolt axis and the end face as the center point, and the maximum distance from the internal hexagonal head as the radius. Take the sum of the length of the long end of the internal hexagonal wrench, the safety distance, and the bolt length as height one, and construct cylinder one along the negative direction of bolt installation. Take the sum of the length of the short end of the internal hexagonal wrench, the safety distance, and the bolt length as height two, and construct cylinder two along the negative direction of bolt installation. S302. Perform interference detection on cylinder one and cylinder two with the fixture respectively. The default detection type is "contact + collision". If both cylinder one (long end) and cylinder two (short end) interfere with the fixture, the hex wrench will not be selected, and the detection will be stopped. If neither cylinder one (long end) nor cylinder two (short end) interferes with the fixture, proceed to step S303. If one end of cylinder one (long end) or cylinder two (short end) does not interfere with the fixture, proceed to step S304. S303. Identify the size of the bolt's internal hexagonal end. Using the intersection of the bolt axis and the end face as the starting point, along the negative direction of bolt installation, first, use the length of the long end of the internal hexagonal wrench as the distance to make the center point, and use the length of the short end of the internal hexagonal wrench as the radius to make surface one; then, use the sum of the length of the long end of the internal hexagonal wrench and the bolt length as the distance to make the center point, and use the length of the short end of the internal hexagonal wrench as the radius to make surface two. Surface one and surface two are used as the standard surfaces of the detection space. Execute step S305. First, use the short end of the Allen wrench as the distance to make the center point, and use the long end of the Allen wrench as the radius to make surface three; then, use the sum of the short end of the Allen wrench and the bolt length as the distance to make the center point, and use the long end of the Allen wrench as the radius to make surface four. Surface three and surface four are used as the standard surfaces of the inspection space. Then, execute step S305. S304. Identify the internal hexagonal end size of the bolt. Taking the intersection of the bolt axis and the end face as the starting point, along the negative direction of bolt installation, first use the length of the non-interfering end as the distance to make the center point, and use the length of the other end as the radius to make surface one; then use the sum of the length of this end and the bolt length as the distance to make the center point, and use the length of the other end as the radius to make surface two. Surface one and surface two are used as the standard surfaces of the detection space. Execute step S305. S305. Surface 1 and Surface 2, which serve as the standard surfaces of the testing space, are subjected to interference testing with the fixture to determine whether the sector angle value of the non-interference range meets the testing standard value. If it does, the disassembly test is qualified.

4. The method for testing the disassemblyability of bolts in fixture design according to claim 1, characterized in that, The detection method for assembling other wrenches in step S3 specifically includes: Assemble the assembly equipment to the bolt position and generate a minimum bounding box profile one with the installation end of the assembly equipment as the size reference. Generate a minimum bounding box profile two with the axial dimension of the minimum bounding box profile one plus the bolt length as the size reference. Determine whether there is any interference between the minimum bounding box profile two and the fixture. If there is no interference, the disassembly test is qualified.

5. A system for detecting bolt disassembly capability in fixture design, characterized in that, include: Import and recognition module: Select the fixture model file and import it into the software; After importing, perform bolt recognition to identify all bolt information within the digital model; Preliminary selection module: Based on bolt information and equipment specifications in the equipment library, preliminary selection of assembly equipment is performed; assembly equipment includes hex wrenches, socket wrenches, and other wrenches; Testing module: If the assembly equipment is an Allen wrench, test whether there is axial interference when the long end and short end of the Allen wrench remove the bolt, and whether there is enough space to unscrew it in the axial direction. If the assembly equipment is a socket wrench, check the interference between the socket and the fixture, and determine whether there is any interference between the socket and other standard parts; A socket wrench testing submodule is provided, including: a cylinder is constructed along the extension rod direction with the sum of the socket radius and the safety distance as the radius, the sum of the socket length and the extension rod length as the height, the intersection of the extension rod and the handle as the center point, and the longest distance from the intersection of the extension rod and the handle to both ends of the handle as the radius; the interference relationship between the cylinder and the fixture is tested, then the interference relationship between the cylinder and other bolts is tested, then the interference relationship between the plane and the fixture is tested, and then the interference relationship between the plane and other bolts is tested. If there is no interference, the disassembly test is qualified. If the assembly equipment is a different type of wrench, determine whether there is interference by generating the minimum bounding box contour; Output module: After the detection is completed, take a screenshot of the corresponding position of the bolt, annotate it using the YOLO model and output it.

6. The system for detecting bolt disassembly in fixture design according to claim 5, characterized in that, The import recognition module includes: First identification unit: For the national standard number and manufacturer's standard number of the bolt, the equipment library is set first, and the part number of the standard bolt is configured. The software traverses the internal bolt number in all the input data and finally records the bolt position information. Second identification unit: When bolts are stored in the same standard assembly, the software first identifies the location of the standard file through an identifier, then iterates through the required bolt models, and finally confirms the bolt location information; The third identification unit: When bolts are stored in different locations, the software identifies the bolts by comparing the dimensions of the geometric model in the fixture CAD file with the dimensions of the standard bolt model, and records the relevant model and location information. Fourth identification unit: For bolts in the form of sheet bodies or envelope bodies, the software traverses the fixture model files for a full search. If models that are both sheet bodies and solids with the same specifications are found, the solid model is preferred. If no solid model is found, the sheet body file is preferred, and the bolt is identified as a bolt. The relevant model and location information are recorded. Fifth identification unit: For cases where none of the above can be identified, manually select the bolt model, and the software will identify the bolt parameter information. Any information that cannot be identified will be added manually.

7. The system for detecting bolt disassembly in fixture design according to claim 5, characterized in that, The testing module includes an internal hex wrench testing submodule, which includes: Cylindrical Unit: Identify the size of the bolt's internal hexagonal end, take the intersection of the bolt axis and the end face as the center point, and the maximum distance from the internal hexagonal as the radius; take the sum of the long end length of the internal hexagonal wrench, the safety distance, and the bolt length as height one, and construct cylinder one along the negative direction of bolt installation; take the sum of the short end length of the internal hexagonal wrench, the safety distance, and the bolt length as height two, and construct cylinder two along the negative direction of bolt installation; First Interference Detection Unit: Interference detection is performed between cylinder one and cylinder two and the fixture, with the default detection type being "contact + collision". If both cylinder one (long end) and cylinder two (short end) interfere with the fixture, the hex wrench is not considered, and the detection is stopped. If neither cylinder one (long end) nor cylinder two (short end) interferes with the fixture, the process moves to the first standard surface unit. If either cylinder one (long end) or cylinder two (short end) does not interfere with the fixture, the process moves to the second standard surface unit. First standard surface unit: Identify the size of the bolt's internal hexagonal end. Taking the intersection of the bolt axis and the end face as the starting point, along the negative direction of bolt installation, first, use the length of the long end of the internal hexagonal wrench as the distance to make the center point, and use the length of the short end of the internal hexagonal wrench as the radius to make surface one; then, use the sum of the length of the long end of the internal hexagonal wrench and the bolt length as the distance to make the center point, and use the length of the short end of the internal hexagonal wrench as the radius to make surface two. Surface one and surface two serve as the standard surface of the detection space, and the second interference detection unit is executed. First, take the short end of the Allen wrench as the distance to the center point, and take the long end of the Allen wrench as the radius to make surface three; then take the sum of the short end of the Allen wrench and the bolt length as the distance to the center point, and take the long end of the Allen wrench as the radius to make surface four. Surface three and surface four are used as the standard surfaces of the detection space, and the second interference detection unit is executed. The second standard surface unit: after identifying the size of the bolt's internal hexagonal end, taking the intersection of the bolt axis and the end face as the starting point, along the negative direction of bolt installation, firstly, using the length of the non-interfering end as the distance to the center point, and using the length of the other end as the radius to create surface one; then, using the sum of the length of this end and the bolt length as the distance to the center point, and using the length of the other end as the radius to create surface two. Surface one and surface two serve as the standard surface of the detection space, and the second interference detection unit is executed. The second interference detection unit: Surface 1 and Surface 2, which serve as the standard surfaces of the detection space, are subjected to interference detection with the fixture to determine whether the sector angle value of the non-interference range can meet the detection standard value. If it can, the disassembly test is qualified.

8. The system for detecting bolt disassembly in fixture design according to claim 5, characterized in that, The detection module includes other wrench detection sub-modules, including: Assemble the assembly equipment to the bolt position and generate a minimum bounding box profile one with the installation end of the assembly equipment as the size reference. Generate a minimum bounding box profile two with the axial dimension of the minimum bounding box profile one plus the bolt length as the size reference. Determine whether there is any interference between the minimum bounding box profile two and the fixture. If there is no interference, the disassembly test is qualified.

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