Method and system for detecting inter-part clearance at a body connection point

Abstract

The present application provides a kind of body connection point part gap detection method and system, comprising: selecting the assembly numerical file needing to do body connection point part gap detection, input model file in software;Identify all connection point numerical files in assembly numerical file and record each connection point center coordinate;Generate normal line through center coordinate, detect the intersecting parts of connection point;Extract the maximum profile of the position where connection point is located, generate the maximum profile cylinder parallel to the normal line direction, generate four equal division normal lines same as the center line direction of cylinder within the maximum profile cylinder;By comparing the detection value between the intersection point of four equal division normal lines and the intersecting parts with the theoretical value, it is judged whether the part gap detection is qualified.The present application completes body connection point part gap detection by software judging and identifying, makes judgment more efficient and accurate, saves time cost and personnel cost.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of automobile automation design, in particular to a kind of body connection point part gap detection method and system. BACKGROUND

[0002] Body connection point such as welding point, SPR (full name Self Piercing Riveting, Chinese: self piercing riveting), FDS (full name Flow Drill Screw, Chinese: flow drill screw riveting) part gap judgment has many aspects on automobile product design and process manufacturing. It is not only an important means to ensure the quality and safety of vehicle, but also an important factor to promote the technological innovation and development of automobile manufacturing industry.

[0003] The gap of the part at the body connection point (welding point, SPR, FDS) is an important parameter in the overall design of the vehicle. By accurately measuring and judging these gaps, engineers can understand the fit between parts, thereby further optimizing the design and improving the design accuracy of the vehicle. This helps to ensure the stability and safety of the vehicle during driving, and improves the user experience.

[0004] For spot welding: spot welding distance and edge distance determine the welding strength between two metal plates. The bonding force between the two plates increases as the welding distance decreases, but when the distance is small to a certain value, the bonding force no longer increases, but becomes harmful. When the distance between two welding points decreases, the reciprocating current increases, but does not cause the welding point to heat up, but rather leads to a decrease in welding quality. If the gap is too small, the weld root may not be fully penetrated, which is an important structure that cannot be allowed to have defects; if the gap is too large, the weld is easy to burn through, resulting in defects such as weld bumps and pores, which will reduce the strength and durability of the welded joint.

[0005] For self-piercing riveting SPR: During self-piercing riveting, the size of the gap between the parts will affect the penetration depth of the rivet and the riveting strength; too large a gap may cause the rivet to not fully penetrate the parts, thereby reducing the riveting strength; a proper gap can ensure that the rivet penetrates the parts correctly and forms an effective riveting connection; too large or too small a gap may result in a decrease in riveting quality, affecting the assembly accuracy and durability of the body.

[0006] For flow drill screw riveting FDS: During flow drill screw connection, the size of the gap between the parts will affect the tightening degree of the screw and the connection strength; too large a gap may cause the screw to not be fully tightened, thereby reducing the connection strength; a proper gap can ensure that the screw is properly tightened and forms a stable connection; too large or too small a gap may result in unstable connection, affecting the safety and reliability of the body.

[0007] In the process of manufacturing, the gap judgment of parts at the body connection points (welding points, SPR, FDS) is a key link to ensure the assembly quality. By strictly controlling the gap, it can ensure the close cooperation between parts and avoid problems such as looseness and abnormal sound; according to the results of gap judgment, the manufacturing process personnel can adjust the process flow, use more suitable assembly methods and tools, so as to improve production efficiency and product quality; by accurately controlling the gap, it can reduce the rework and scrap caused by improper assembly, thereby reducing the production cost.

[0008] With the continuous development of the automobile manufacturing industry, the judgment of the gap between parts at the body connection points is also becoming more and more demanding. In order to meet the market demand and the increasing product quality requirements, automobile manufacturers need to continuously innovate and develop new measurement technology and methods. Through accurate measurement and judgment of the gap, it can provide strong support for technological innovation and development.

[0009] At present, the gap judgment at the connection point still needs to be judged manually, which needs to measure each point and perform planing and cutting processing, completely relying on the experience of engineers, the required time is uncertain and is greatly affected by subjective factors, consumes a long time and has large manual error. SUMMARY

[0010] The present application provides a kind of body connection point parts gap detection method and system, and the gap detection of parts at body connection point is completed by software judgment and identification, so that judgment and audit are more efficient and accurate, save time cost and personnel cost.

[0011] To achieve the above object, the technical scheme of the present application is as follows:

[0012] A kind of body connection point parts gap detection method, comprising:

[0013] S1, select the assembly model file that needs to do body connection point parts gap detection, input the model file in the software;

[0014] S2, identify all connection point models in the assembly model file and record the center coordinates of each connection point; generate a normal line through the center coordinates to detect the intersecting parts of the connection point;

[0015] S3, extract the maximum profile at the position of the connection point, generate a maximum profile cylinder parallel to the normal direction, and generate four equal division normal lines in the same direction as the center line of the cylinder in the maximum profile cylinder;

[0016] S4, compare the detection value of the distance between the four equal division normal lines and the intersection points of the intersecting parts with the theoretical value to judge whether the part gap detection is qualified.

[0017] Further, in step S2, for the identified connection point, a'measure inertia' command is called to perform center detection and record the center coordinates.

[0018] Further, in step S2, the method of generating the normal line includes: detecting the part closest to the center of the connection point according to the center coordinates of the connection point, and generating a normal line through the center and the closest part.

[0019] Further, in step S2, the method of detecting intersecting parts includes: calling a 'collision' command, using the normal line as the detection direction, performing collision detection on the connection point and each part, and obtaining the detection result according to the displayed interference result. The part having an interference relationship with the connection point is the intersecting part.

[0020] Further, step S4 specifically includes:

[0021] Each bisector intersects each intersecting part to generate intersection points, and the distance value between the two intersection points of the largest bisector is recorded as the detection value of the bisector, and the detection values A1, A2, A3, A4 of the four bisectors are obtained.

[0022] Each bisector generates two intersection points with each intersecting part, and the distance between the two intersection points is the intersection point distance of the corresponding intersecting part. The intersection point distances of all intersecting parts are summed as the theoretical value of the bisector, and the theoretical values B1, B2, B3, B4 of the four bisectors are obtained.

[0023] The four sets of detection values and theoretical values are compared. If they are all the same, it is determined that the part gap detection is qualified. If one or more sets are different, it is determined that the part gap detection is unqualified, and the position, detection value, theoretical value, and difference between the detection value and the theoretical value of the corresponding point are output.

[0024] Another aspect of the present application also provides a part gap detection system for a vehicle body connection point, comprising:

[0025] The input module: select the assembly model file that needs to be detected for the part gap at the vehicle body connection point, and input the model file in the software;

[0026] The recognition module: recognizes all connection point models in the assembly model file and records the center coordinates of each connection point; generates a normal line through the center coordinates to detect the intersecting parts of the connection point;

[0027] The division module: extracts the maximum profile at the position of the connection point, generates a maximum profile cylinder parallel to the normal line direction, and generates four bisector normal lines in the same direction as the center line of the cylinder.

[0028] The detection module: through the comparison between the detection value and the theoretical value of the distance between the intersection points of the four bisector lines and the intersecting parts, it is judged whether the part gap detection is qualified.

[0029] Further, the identification module includes: for the identified connection point number module, calling the "measurement inertia" command to detect the center and record the center coordinates.

[0030] Further, the identification module includes: according to the center coordinates of the connection point, detecting the part closest to the center of the connection point, and generating a normal line through the center and the closest part.

[0031] Further, the identification module includes: calling the "collision" command, taking the normal line as the detection direction, and performing collision detection on the connection point and each part, and obtaining the detection result according to the displayed interference result. The part having interference relationship with the connection point is the intersecting part.

[0032] Further, the detection module includes:

[0033] The detection value unit: each bisector line intersects with each intersecting part to generate intersection points, and records the distance value between the two largest intersection points of the bisector line as the detection value of the bisector line, and obtains the detection values A1, A2, A3 and A4 of the four bisector lines.

[0034] The theoretical value unit: each bisector line generates two intersection points with each intersecting part, and the distance between the two intersection points is taken as the intersection point distance of the corresponding intersecting part. The intersection point distances of all intersecting parts are summed up as the theoretical value of the bisector line, and the theoretical values B1, B2, B3 and B4 of the four bisector lines are obtained.

[0035] The comparison unit: compare the four groups of detection values and theoretical values. If they are all the same, it is determined that the part gap detection is qualified. If one or more groups are different, it is determined that the part gap detection is unqualified, and the position, detection value, theoretical value and difference between the detection value and the theoretical value of the corresponding point are output.

[0036] Compared with the prior art, the present application has the following advantages:

[0037] 1. The present application provides a logic for part gap detection at the connection point by software. The steps of manual part gap detection at the connection point are simplified to software operation through software judgment and identification, and after the corresponding logic rules are input, the judgment and review are more efficient and accurate, reducing the demand for professionalism of car body design, saving time and personnel costs.

[0038] 2. On the basis of the software mode of the application, with the continuous optimization and iteration of the algorithm, the subsequent detection and judgment will be more and more intelligent, and the overall data of the judgment can be customized and changed, providing reference samples for the subsequent software development of intelligent design based on deep learning. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 is a flowchart of embodiment 1 of the application;

[0040] Figure 2 is a software main interface diagram of embodiment 1 of the application;

[0041] Figure 3 is a software internal logic diagram of embodiment 1 of the application;

[0042] Figure 4 is a connection point center coordinate diagram of embodiment 1 of the application;

[0043] Figure 5 is a normal line generation diagram of embodiment 1 of the application;

[0044] Figure 6 is a maximum contour cylinder diagram of embodiment 1 of the application;

[0045] Figure 7 is a four-equal-division normal line diagram of embodiment 1 of the application;

[0046] Figure 8 is a first-equal-division normal line detection value diagram of embodiment 1 of the application;

[0047] Figure 9 is a second-equal-division normal line detection value diagram of embodiment 1 of the application;

[0048] Figure 10 is a first-equal-division normal line theoretical value diagram of embodiment 1 of the application;

[0049] Figure 11 is a second-equal-division normal line theoretical value diagram of embodiment 1 of the application;

[0050] Figure 12 is a screenshot line definition diagram of embodiment 1 of the application;

[0051] Figure 13 is a cutting plane generation diagram of the screenshot of embodiment 1 of the application;

[0052] Figure 14 is a cutting plane effect diagram of the screenshot of embodiment 1 of the application;

[0053] Figure 15 is a system structure diagram of embodiment 2 of the application. DETAILED DESCRIPTION

[0054] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0055] In order to make the purpose and characteristics of the present application more obvious and easy to understand, the specific embodiments of the present application are further described below in combination with the drawings.

[0056] Embodiment 1

[0057] The part gap detection method at the body connection point provided in the embodiment includes, as shown in the figure, the following steps: Figure 1

[0058] S1, select the assembly model file that needs to be detected for the part gap at the body connection point, and input the model file in the software.

[0059] The part gap detection method at the body connection point of the present application is realized by software, so it is required to select the model file of the body assembly for input in the software interface, and to identify the connection point model from the model file. The function of this step is to realize the selection and input of the assembly model file.

[0060] As shown in the figure, it is the main interface of the part gap detection at the body connection point of the software. Click “select product model” on the interface, and the software reads the model file through the API function call of the three-dimensional design software. The three-dimensional design software used in the embodiment is CATIA, and the model under the SM node of CATIA is read, and then the user is allowed to click to select. After selection, it is displayed in the display box. Figure 2

[0061] S2, identify all connection point models in the assembly model file and record the center coordinates of each connection point; generate a normal line through the center coordinates to detect the intersecting parts of the connection point.

[0062] The internal execution logic of the software after the model file is input is shown in the figure. First, select the connection point type (spot welding, SPR, FDS) that needs to be identified and detected, or select multiple or all, and then select the identifier of the connection point type that needs to be identified and detected. The identifier needs to be searched in the input model. If there is no corresponding identifier in the menu at the software level, manually add it by clicking the “+” behind it. The identifier is a required item, and after the identifier is input, the identification function in the model can be performed. Figure 3

[0063] ​​​The software will search the input model one by one through the identification mark, model judgment and connection point type judgment, identify the model of the connection point (spot welding, SPR, FDS) and detect the center of the connection point (if it is a welding point, the center is its spherical center, and if it is SPR or FDS, the center is its center of gravity), and call the "measure inertia" command to record the coordinates of the center of gravity / ball center, complete the connection point position determination. As shown in Figure 4 If there is a point and a model, the center of gravity / center measurement is not needed.

[0064] The method for detecting the intersecting parts of the connection point includes:

[0065] According to the center coordinates of the connection point, the part closest to the center of the connection point is detected.

[0066] A normal line is generated for the connection point according to the center coordinates and the plane of the closest part, for example, the connection point is a SPR rivet point, the center is the center of gravity of the SPR rivet point, and the normal line is generated as shown in Figure 5 The length of the normal line is the configuration item, which can be adjusted according to the needs. In this embodiment, the length of the normal line is 5mm from the center of gravity of the SPR rivet point at both ends.

[0067] The relationship between the connection point and the parts is preliminarily judged, and the "collision" command of CATIA is called to perform collision detection of the connection point and each part with the normal line as the detection direction. If there is no interference between the part and the connection point, the position of the point will not be judged. If there is an interference relationship, the part is the intersecting part of the connection point.

[0068] S3, extract the maximum profile of the position of the connection point, generate a maximum profile cylinder parallel to the normal line direction, and generate four equal division normal lines in the same direction as the center line of the cylinder in the maximum profile cylinder.

[0069] The cylinder is generated as shown in Figure 6 The position of the connection point is the position of the head of the connection point, and the head of the connection point is identified by intersecting the part plate or thickness. The surface of the intersecting part closest to the head of the connection point is the position of the connection point, and the "extract function" is called to perform extraction and identification operations. The maximum profile cylinder is a cylinder that can cover the connection point without interference with other parts.

[0070] As shown in Figure 7 Four equal division normal lines are generated in the cylinder profile, and the direction is the same as the center line.

[0071] The method for generating four equal division normal lines includes:

[0072] 1. Identify the end face boundary of the cylinder;

[0073] 2. Generate a random angle ;

[0074] 3. Take the radius of the cylinder as r;

[0075] 4. Calculate the initial point coordinates within the identified cylinder end face boundary;

[0076] ; ;

[0077] 5. Draw the first normal line according to the initial point coordinates, and then generate all four equal division normal lines according to the first normal line, with the curve distribution of the four equal division normal lines being 0 / 0.25 / 0.5 / 0.75.

[0078] S4. Determine whether the part gap detection is qualified by comparing the detection value of the distance between the four equal division normal lines and the intersection points of the intersecting parts with the theoretical value.

[0079] Each of the four equal division normal lines intersects with each intersecting part to generate intersection points, and the distance between the two largest intersection points is taken as the detection value of the equal division normal line, and the detection values A1, A2, A3, and A4 of the four equal division normal lines are obtained by this operation; as shown in Figure 8 、 9 , A1 and A2 detection values are shown respectively.

[0080] Each equal division normal line generates two intersection points with each intersecting part, and the distance between the two intersection points is taken as the intersection point distance of the corresponding intersecting part, and the sum of the intersection point distances of all intersecting parts is taken as the theoretical value of the equal division normal line, and the theoretical values B1, B2, B3, and B4 of the four equal division normal lines are obtained by this operation; as shown in Figure 10 、 11 , B1 and B2 theoretical values are shown respectively.

[0081] Compare the four sets of detection values and theoretical values, i.e. A1 and B1, A2 and B2, A3 and B3, A4 and B4, if the four comparisons are the same, the part gap detection is determined to be qualified, and if one or more groups are different, the part gap detection is determined to be unqualified, and the position, detection value, theoretical value, and difference between the detection value and the theoretical value of the corresponding point are output.

[0082] The software only displays the screenshot of the connection point whose part gap detection is unqualified, and the screenshot shows the planing operation of the connection point position, as shown in Figure 12 , the planing operation is performed along the equal division normal line and its diagonal normal line and the face formed by the point center of gravity. Figure 13 The cutting plane generated is shown in Figure 14 , and the cutting operation effect diagram is shown.

[0083] The embodiment provides the logic of software for detecting the part gap at the body connection point, simplifies the step of manually detecting the part gap at the connection point into software operation through the judgment and recognition of software, judges and audits more efficiently and accurately after inputting the corresponding logic rules, reduces the requirement of the body design on the professional degree, and saves the time cost and personnel cost.

[0084] Embodiment 2

[0085] The embodiment provides a part gap detection system at a body connection point, as shown in the accompanying drawings, comprising: Figure 15

[0086] The input module: select the assembly number module file which needs to detect the part gap at the body connection point, and input the model file in the software;

[0087] The recognition module: recognize all connection point number modules in the assembly number module file and record the center coordinates of each connection point; generate a normal line through the center coordinates to detect the intersecting parts of the connection point;

[0088] The equal division module: extract the maximum profile at the position of the connection point, generate a maximum profile cylinder parallel to the normal line direction, and generate four equal division normal lines in the same direction as the center line of the cylinder in the maximum profile cylinder;

[0089] The detection module: compare the detection value of the distance between the four equal division normal lines and the intersection points of the intersecting parts with the theoretical value to determine whether the part gap detection is qualified.

[0090] Further, the recognition module comprises: for the recognized connection point number module, calling the "measurement inertia" command to detect the center and record the center coordinates.

[0091] Further, the recognition module comprises: detecting the part closest to the center of the connection point according to the center coordinates of the connection point, and generating a normal line through the center and the closest part.

[0092] Further, the recognition module comprises: calling the "collision" command to perform collision detection on the connection point and each part with the normal line as the detection direction, and obtaining the detection result according to the displayed interference result. The parts having the interference relationship with the connection point are the intersecting parts.

[0093] Further, the detection module comprises:

[0094] The detection value unit: each equal division normal line intersects with each intersecting part to generate an intersection point, and records the distance value between the two largest intersection points of the equal division normal line as the detection value of the equal division normal line, to obtain the detection values A1, A2, A3 and A4 of the four equal division normal lines;

[0095] ​Theoretical value unit: each equal division line and each intersecting part generates two intersection points, the distance between the two intersection points is the intersection point distance of the corresponding intersecting part, the intersection point distances of all intersecting parts are summed as the theoretical value of the equal division line, and the theoretical values B1, B2, B3 and B4 of the four equal division lines are obtained;

[0096] Comparison unit: compare the four groups of detection values with the theoretical values, if all are the same, it is determined that the part gap detection is qualified, and if one group and above are different, it is determined that the part gap detection is unqualified, and the position, detection value, theoretical value and difference between the detection value and the theoretical value of the corresponding point are output.

[0097] The part gap detection system at the body connection point provided in the embodiment can implement the part gap detection method at the body connection point in embodiment 1, and has the same technical effects as embodiment 1.

[0098] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for detecting gaps between parts at vehicle body connection points, characterized in that, include: S1. Select the assembly model file for which you need to perform gap detection at the body connection points and input the model file into the software. S2. Identify all connection point models in the assembly model file and record the center coordinates of each connection point; generate normals using the center coordinates and detect intersecting parts at the connection points; S3. Extract the maximum contour at the location of the connection point, generate a maximum contour cylinder parallel to the normal direction, and generate four equally bisecting normals in the cylinder with the same direction as the center line of the cylinder. S4. By comparing the detected value of the distance between the intersection point of the four equally divided normal lines and the intersecting parts with the theoretical value, it is determined whether the gap detection of the parts is qualified.

2. The method for detecting gaps between parts at vehicle body connection points according to claim 1, characterized in that, In step S2, for the identified connection point digital model, the "Measure Inertia" command is called to perform center detection and record the center coordinates.

3. The method for detecting gaps between parts at vehicle body connection points according to claim 1, characterized in that, In step S2, the method for generating normals includes: based on the center coordinates of the connection point, detecting the part closest to the center of the connection point, and generating normals through the center and the nearest part.

4. The method for detecting gaps between parts at vehicle body connection points according to claim 1, characterized in that, The method for detecting intersecting parts in step S2 includes: calling the "collision" command, using the normal as the detection direction, performing collision detection on the connection point and each part, obtaining the detection result based on the displayed interference result, and identifying the parts that have an interference relationship with the connection point as intersecting parts.

5. The method for detecting gaps between parts at vehicle body connection points according to claim 1, characterized in that, Step S4 specifically includes: Each equally divided normal line intersects with each intersecting part to generate an intersection point. The distance between the two intersection points with the largest value of the equally divided normal line is recorded as the detection value of the equally divided normal line, and the detection values ​​A1, A2, A3 and A4 of the four equally divided normal lines are obtained. Each bisecting normal line produces two intersection points with each intersecting part. The distance between these two intersection points is taken as the intersection point distance of the corresponding intersecting part. The sum of the intersection point distances of all intersecting parts is taken as the theoretical value of the bisecting normal line, resulting in the theoretical values ​​B1, B2, B3, and B4 of the four bisecting normal lines. The four sets of test values ​​are compared with the theoretical values. If they are all the same, the part gap test is deemed qualified. If one or more sets are different, the part gap test is deemed unqualified. The corresponding position, test value, theoretical value, and the difference between the test value and the theoretical value are output.

6. A system for detecting gaps between parts at vehicle body connection points, characterized in that, include: Input module: Select the assembly model file for which you need to perform gap detection at the body connection points and input the model file into the software; Identification module: Identifies all connection point digital models in the assembly digital model file and records the center coordinates of each connection point; generates normals based on the center coordinates and detects intersecting parts at the connection points; Equal division module: Extract the maximum contour at the location of the connection point, generate the maximum contour cylinder parallel to the normal direction, and generate four equal division normals in the cylinder with the same direction as the center line of the cylinder. Detection module: By comparing the detected value of the distance between the intersection point of the four equally divided normal lines and the intersecting parts with the theoretical value, it determines whether the gap detection of the parts is qualified.

7. The system for detecting gaps between parts at vehicle body connection points according to claim 6, characterized in that, The identification module includes calling the "Measure Inertia" command to perform center detection and record the center coordinates for the identified connection point digital model.

8. The system for detecting gaps between parts at vehicle body connection points according to claim 6, characterized in that, The identification module includes: detecting the part closest to the center of the connection point based on the center coordinates of the connection point, and generating a normal through the center and the nearest part.

9. The system for detecting gaps between parts at vehicle body connection points according to claim 6, characterized in that, The identification module includes: calling the "collision" command, using the normal as the detection direction, performing collision detection on the connection point and each part, obtaining the detection result based on the displayed interference result, and identifying the parts that have an interference relationship with the connection point as intersecting parts.

10. The part gap detection system at the vehicle body connection point according to claim 6, characterized in that, The detection module includes: Detection value unit: Each equally divided normal line intersects with each intersecting part to generate an intersection point. The distance between the two largest intersection points of the equally divided normal line is recorded as the detection value of the equally divided normal line, and the detection values ​​A1, A2, A3, and A4 of the four equally divided normal lines are obtained. Theoretical value unit: Each equally divided normal line produces two intersection points with each intersecting part. The distance between these two intersection points is taken as the intersection point distance of the corresponding intersecting part. The sum of the intersection point distances of all intersecting parts is taken as the theoretical value of the equally divided normal line, thus obtaining the theoretical values ​​B1, B2, B3, and B4 of the four equally divided normal lines. Comparison Unit: The four sets of test values ​​are compared with the theoretical values. If they are all the same, the part gap test is deemed qualified. If one or more sets are different, the part gap test is deemed unqualified. The unit outputs the position of the corresponding point, the test value, the theoretical value, and the difference between the test value and the theoretical value.

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