Method and system for automatically checking fitting degree of welding lap joint surfaces

Abstract

The invention provides a method and system for automatically checking the fitting degree of a welding lap joint surface. According to the method, part information is obtained by retrieving a welding spot file, normal lines of curved surfaces of all parts are made through welding spot sphere centers, and intersection points of the normal lines and the parts are calculated; comparing the coordinates of the intersection points in pairs, and counting the number of unique points with unequal coordinates; and when the number of the unique points is 2, performing coordinate exchange and fitting verification. In the lamination verification process, calculating vectors formed by adjacent points, unitizing the vectors, then calculating a dot product, and judging whether the vectors are in the same direction or not; and meanwhile, checking whether the coordinate values of adjacent points are equal in a tolerance range. The invention further provides a system for realizing the method. The system comprises a welding spot information acquisition module, a normal generation module, an intersection point calculation module and a fitting degree detection module. According to the method, a fitting problem in a three-dimensional space is converted into a vector analysis problem in a two-dimensional plane, the calculation complexity is simplified, and the detection efficiency and accuracy are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile manufacturing, and in particular to a method, a system and an electronic device for automatically checking the fit of a welding overlap surface. Background Art

[0002] In the process of body-in-white design, there are a large number of welding points, which are usually placed in geometric sets named after the welding parts. For example, when three sheet metal parts K1, K2, and K3 need to be welded, the corresponding geometric sets will be named K1vsK2vsK3, where "vs" is used as the interval discrimination symbol. Depending on the number of welded sheet metals, welding can be divided into different types such as two-layer welding and three-layer welding.

[0003] In the prior art, a weld point is usually represented as a sphere with a center point in a geometry set. Sheet metal data connected using the same weld point needs to remain in a fitted state. However, since the body-in-white usually contains hundreds of parts, it currently relies mainly on manual inspection of these parts one by one to see if they fit together. This traditional manual inspection method has the following problems:

[0004] 1. The inspection efficiency is low, which requires a lot of manpower and time;

[0005] 2. Omissions are prone to occur, reducing the reliability of inspection;

[0006] 3. There is a lack of standardized inspection procedures, and the inspection results often depend on the experience and concentration of the inspectors;

[0007] 4. The consistency and accuracy of the inspection cannot be guaranteed. Summary of the invention

[0008] In view of the problem that manual inspection of weld points in the prior art is time-consuming and prone to omissions, the present invention provides a method, system and electronic equipment for automatically checking the fit of weld lap surfaces to improve work efficiency and work quality and reduce the error rate of data design.

[0009] To achieve the above object, in a first aspect, the present invention provides a method for automatically checking the fit of a welded lap joint, comprising the following steps:

[0010] Retrieve solder joint files and extract part number information;

[0011] Draw the normal line of each part surface through the center of the welding point sphere;

[0012] Calculate the intersection point of each normal line with the corresponding part;

[0013] The obtained intersection points are tested for fit.

[0014] In some optional embodiments of the present invention, the fit detection includes:

[0015] Compare the coordinates of the intersection points pairwise to determine the number x of unique points whose coordinates are not equal to each other;

[0016] When x=2, coordinate exchange and fit verification are performed;

[0017] When x≠2, it is determined that the welding lap surfaces are not in contact.

[0018] In some optional embodiments of the present invention, the coordinate exchange and fit verification include:

[0019] Take one of the unique points as the path starting point and the other unique point as the path end point, and exchange the coordinates of the intersection points so that the path starting point is at P1 and the path end point is at P 2n Location;

[0020] Check whether adjacent intersection points overlap in sequence;

[0021] Calculate the vectors between adjacent intersection points and determine whether they are in the same direction;

[0022] When all vectors are in the same direction and adjacent intersection points coincide, the weld lap surfaces are considered to be in close contact.

[0023] Preferably, the coordinate exchange includes:

[0024] Let a unique point be P a , and another unique point is denoted as P b ;

[0025] P a The coordinate values ​​of P1 are exchanged with the coordinate values ​​of P a The coordinate values ​​of another intersection point belonging to the same part are exchanged with the coordinate values ​​of P2;

[0026] P b The coordinate values ​​of P 2n The coordinate values ​​of P are exchanged. b The coordinate value of another intersection point belonging to the same part is the same as P 2n-1 The coordinate values ​​of .

[0027] Further preferably, the fit verification includes:

[0028] Calculate vector P1P2 and vector P 2n-1 P 2n ;

[0029] When vector P1P2 and vector P 2n-1 P 2n When the directions are different, it is determined that the welding lap surfaces are not fitted;

[0030] When vector P1P2 and vector P 2n-1 P2n When in the same direction, check whether the coordinate values ​​of P2 and subsequent intersection points are equal.

[0031] Further preferably, when a point P with the same coordinate value as P2 is found c When P c The coordinate values ​​of are exchanged with those of P3;

[0032] Will be with P c The coordinate values ​​of another intersection point belonging to the same part are exchanged with the coordinate values ​​of P4;

[0033] Calculate vector P3P4;

[0034] When the vector P3P4 and the vector P1P2 are in different directions, it is determined that the welding lap surface is not fitted;

[0035] When vector P3P4 and vector P1P2 have the same direction, repeat the above operation.

[0036] Further preferably, when a 2n The points with the same coordinate values ​​are used to determine whether the weld overlap surfaces are aligned; if all points are compared but no points with P are found, 2n The equal points determine that the welding lap surfaces do not fit well.

[0037] Still further preferably, the coordinates of the points being equal means that the differences of the coordinate components are all within a preset tolerance range.

[0038] In some optional embodiments of the present invention, the vectors being in the same direction means that: within an error range, the absolute value of the dot product of the unit vectors is equal to 1.

[0039] In a second aspect, the present invention provides a system for automatically checking the fit of a welded lap joint, comprising:

[0040] Solder point information acquisition module, used to retrieve solder point files and extract part information;

[0041] Normal generation module, used to generate the normal lines of each part surface passing through the center of the welding point;

[0042] Intersection calculation module, used to calculate the intersection of normal lines and parts;

[0043] The fit detection module is used to perform fit detection.

[0044] In some optional embodiments of the present invention, the fit detection module includes:

[0045] Unique point counting unit, used to count the number of intersections with different coordinates;

[0046] A coordinate exchange unit, used for performing the exchange of intersection coordinate values;

[0047] A vector calculation unit, used to calculate and compare vectors between adjacent intersection points;

[0048] The fit determination unit is used to determine the fit degree according to the vector isotropy and point coincidence.

[0049] Preferably, the system further comprises:

[0050] A data storage module, used to store solder joint information, part information and test results;

[0051] Parameter setting module, used to set coordinate tolerance and vector error range;

[0052] The result output module is used to generate the test report.

[0053] Further preferably, the parameter setting module includes:

[0054] A coordinate tolerance setting unit is used to set the tolerance range for point coincidence determination;

[0055] A vector error setting unit, used to set the error range of vector same-direction determination;

[0056] The parameter verification unit is used to verify the validity of the set parameters.

[0057] In a third aspect, the present invention provides an electronic device comprising a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other via the communication bus; the memory is used to store computer programs; and the processor is used to implement any method of automatically checking the fit of welding lap surfaces as described in the first aspect when executing the program stored in the memory.

[0058] The beneficial effects of the present invention are: the present invention can automatically and efficiently check whether the welded overlap surface is fitted, reduce the workload of manual inspection, improve work efficiency, and reduce the data design error rate. The present invention is suitable for checking weld points in the process of body-in-white design.

[0059] 1. Improve work efficiency: The present invention can quickly and accurately determine whether the welded lap joint is fitted; it uses an automated method to check whether the welded lap joint is fitted, which reduces the workload of manual inspection and greatly improves work efficiency. At the same time, by counting the number of unique points, it can quickly screen out the non-fitting situations and improve the detection efficiency.

[0060] 2. Reduce the error rate: The present invention makes the surface normal through the center of the weld point and calculates the intersection of the normal and the part, thereby converting the fitting problem in the three-dimensional space into a vector analysis problem in the two-dimensional plane, simplifying the calculation complexity; reducing the omissions that may occur during manual inspection, reducing the data design error rate, and improving the work quality.

[0061] 3. Strong applicability: It is suitable for checking welding points in the process of body-in-white design, especially for multi-layer welding such as two-layer welding and three-layer welding, and has broad application prospects;

[0062] 4. The present invention adopts a method combining coordinate exchange and vector isotropy analysis, which can accurately identify the fitting chain and ensure the reliability of the detection result. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] In order to more clearly illustrate the technical solutions of the embodiments disclosed in the present invention, the drawings of the embodiments will be briefly introduced below. These drawings are only used for illustrative purposes and are not intended to limit the protection scope of the present invention.

[0064] Figure 1 It is a schematic flow chart of a method for automatically checking the fit of a welding lap surface provided by an embodiment of the present invention;

[0065] Figure 2 It is a schematic diagram of the normal line of the curved surface made by the two-layer welding of the present invention;

[0066] Figure 3 It is a schematic diagram of finding the intersection point of two-layer welding of the present invention;

[0067] Figure 4 It is a schematic diagram of the coordinates of four intersection points of two-layer welding of the present invention;

[0068] Figure 5 It is a structural block diagram of a system for automatically checking the fit of welding lap surfaces provided by an embodiment of the present invention;

[0069] Figure 6 It is a schematic diagram of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0070] The technical solution of the present invention (including the preferred technical solution) is further described in detail below by means of the accompanying drawings and by listing some optional embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0071] Example 1

[0072] like Figure 1 As shown, this embodiment provides a method for automatically checking the fit of a welding overlap surface, comprising the following steps:

[0073] Retrieve solder joint files and extract part number information;

[0074] Draw the normal line of each part surface through the center of the welding point sphere;

[0075] Calculate the intersection point of each normal line with the corresponding part;

[0076] The obtained intersection points are tested for fit.

[0077] For correctly fitted multi-layer welding, there must be a continuous path from the starting point to the end point. This path is formed by connecting the common points (intersections) between adjacent parts. Adjacent vectors on the path must be in the same direction, indicating that the surface direction is consistent.

[0078] In some embodiments of the present invention, the coordinates of the intersection points are compared pairwise to determine the number x of unique points whose coordinates are not equal to each other;

[0079] When x=2, coordinate exchange and fit verification are performed;

[0080] When x≠2, it is determined that the welding lap surfaces are not in contact.

[0081] In some embodiments of the present invention, one of the unique points is used as the path starting point and the other unique point is used as the path end point. The coordinates of the intersection points are exchanged so that the path starting point is located at position P1 and the path end point is located at position P2. 2n Location;

[0082] Check whether adjacent intersection points overlap in sequence;

[0083] Calculate the vectors between adjacent intersection points and determine whether they are in the same direction;

[0084] When all vectors are in the same direction and adjacent intersection points coincide, the weld lap surfaces are considered to be in close contact.

[0085] The unique point of the quantity is used as the unique starting point and end point, and the middle points must be equal to each other to reflect the fitting relationship. The consistent direction of the vector ensures the continuity of the curve.

[0086] In some optional embodiments of the present invention, a unique point is recorded as P a , and another unique point is denoted as P b ;

[0087] P a The coordinate values ​​of P1 are exchanged with the coordinate values ​​of P a The coordinate values ​​of another intersection point belonging to the same part are exchanged with the coordinate values ​​of P2;

[0088] P b The coordinate values ​​of P 2n The coordinate values ​​of P are exchanged. b The coordinate value of another intersection point belonging to the same part is the same as P 2n-1 The coordinate values ​​of .

[0089] In some optional embodiments of the present invention, the vectors P1P2 and P are calculated. 2n-1 P 2n ;

[0090] When vector P1P2 and vector P 2n-1 P 2n When the directions are different, it is determined that the welding lap surfaces are not fitted;

[0091] When vector P1P2 and vector P 2n-1 P 2n When in the same direction, check whether the coordinate values ​​of P2 and subsequent intersection points are equal.

[0092] In some optional embodiments of the present invention, when a point P with the same coordinate value as P2 is found, c When P c The coordinate values ​​of are exchanged with those of P3;

[0093] Will be with P c The coordinate values ​​of another intersection point belonging to the same part are exchanged with the coordinate values ​​of P4;

[0094] Calculate vector P3P4;

[0095] When the vector P3P4 and the vector P1P2 are in different directions, it is determined that the welding lap surface is not fitted;

[0096] When vector P3P4 and vector P1P2 have the same direction, repeat the above operation.

[0097] In some optional embodiments of the present invention, when a 2n The points with the same coordinate values ​​are used to determine whether the weld overlap surfaces are aligned. If no points with the same coordinate values ​​are found after all points are compared, 2n The equal points determine that the welding lap surfaces do not fit well.

[0098] In some optional embodiments of the present invention, equality of coordinates of points means that the difference of each coordinate component is within a preset tolerance range.

[0099] In some optional embodiments of the present invention, the vectors being in the same direction means that: within an error range, the absolute value of the dot product of the unit vectors is equal to 1.

[0100] The process of judging whether the vectors are in the same direction:

[0101] Suppose there are two vectors v1 and v2. The steps to determine whether they are in the same direction are:

[0102] 1. Unitization processing:

[0103] v 1_unit =v1 / |v1| (|v1| represents the modulus length of v1)

[0104] v 2_unit =v2 / |v2| (|v2| represents the modulus length of v2)

[0105] 2. Calculate the dot product:

[0106] dot product = v 1_unit ×v 2_unit

[0107] Dot product = x1×x2+y1×y2+z1×z2

[0108] 3. Determine the same direction:

[0109] If the two vectors are exactly in the same direction, the dot product = 1

[0110] If the two vectors are completely opposite, the dot product = -1

[0111] Therefore, we use the absolute value of the dot product to judge. When |dot product|≈1, it means that the vectors are in the same or opposite directions.

[0112] Example 2

[0113] like Figure 1 As shown, this embodiment provides a method for automatically checking the fit of a welding overlap surface, comprising the following steps:

[0114] Retrieve solder joint files.

[0115] Extract the part number in the solder joint file and set it as K1, K2, K3, ..., K n .

[0116] Let the total number of extracted part numbers be n.

[0117] Draw the normal line of the surface of part K1 through the center of the welding point P0, and get the straight line L1.

[0118] Through the welding point sphere center P0, make the normal line of the surface of part K2 to get the straight line L2.

[0119] …

[0120] Through the welding point ball center P0, make parts K n The normal of the surface gives the straight line L n .

[0121] Take the intersection of the straight line L1 and the corresponding part K1 to obtain points P1 and P2,

[0122] Take the intersection of the straight line L2 and the corresponding part K2 to obtain points P3 and P4,

[0123] …

[0124] Take the straight line L n With corresponding parts K nThe intersection point is P. 2n-1 , P 2n .

[0125] For the point set {P1, P2, ..., P 2n-1 , P 2n} to compare the coordinates of each point in the array and determine the number x of unique points whose coordinates are not equal. If x = 2, continue; otherwise, report an error.

[0126] Let a unique point be P a , and another unique point is denoted as P b , P a The coordinate values ​​of P1 are exchanged with the coordinate values ​​of P a The coordinate value of another intersection point belonging to the same part is exchanged with the coordinate value of P2; b The coordinate values ​​of P 2n The coordinate values ​​of P are exchanged. b The coordinate value of another intersection point belonging to the same part is the same as P 2n-1 The coordinate values ​​of .

[0127] Calculate vector P1P2 and vector P 2n-1 P 2n ;

[0128] When vector P1P2 and vector P 2n-1 P 2n When the directions are different, the welding overlap surface is judged to be not in contact and an error is reported;

[0129] When vector P1P2 and vector P 2n-1 P 2n Same direction, and P2=P 2n When P2≠P 2n , continue to check whether the coordinate values ​​of P2 and subsequent intersection points are equal.

[0130] Connect P2 and P3 to P 2n-1 Compare one by one to find the points that are equal to P2. If the number of equal points is not 1, an error is reported. Otherwise, the point is set to P. c ,

[0131] P c The coordinates of P3 are exchanged with the coordinates of P c The coordinate values ​​of another intersection point belonging to the same part are exchanged with those of P4.

[0132] Calculate vector P3P4;

[0133] When the vector P3P4 and the vector P1P2 are in different directions, it is determined that the welding overlap surface is not fitted and an error is reported;

[0134] When the vector P3P4 is in the same direction as P1P2, and P4=P 2n When P4≠P 2n , continue to check whether the coordinate values ​​of P4 and subsequent intersection points are equal.

[0135] Connect P4 and P5 to P 2n-1 Compare one by one to find the points that are equal to P4. If the number of equal points is not 1, an error is reported. Otherwise, the point is set to P. c ,

[0136] P c The coordinates of P5 are exchanged with the coordinates of P c The coordinate values ​​of another intersection point belonging to the same part are exchanged with those of P6.

[0137] Calculate vector P5P6;

[0138] When the vector P5P6 and the vector P1P2 are in different directions, it is determined that the welding overlap surface is not fitted and an error is reported;

[0139] When vector P5P6 is in the same direction as P1P2, and P6 = P 2n When P6≠P 2n , continue to check whether the coordinate values ​​of P6 and subsequent intersection points are equal.

[0140] …

[0141] P 2n-4 With P 2n-3 , P 2n-2 , P 2n-1 Compare them one by one and find out 2n-4 Equal points. If the number of equal points is not 1, an error is reported. Otherwise, the point is set to P. c ,

[0142] P c The coordinate values ​​of P 2n-3 The coordinate values ​​of P c The coordinate value of another intersection point belonging to the same part is the same as P 2n-2 The coordinate values ​​of .

[0143] Calculate the vector P 2n-3 P 2n-2 ;

[0144] When the vector P 2n-3 P 2n-2 When the directions are different from those of vectors P1P2, it is determined that the welding overlap surfaces are not fitted and an error is reported;

[0145] When the vector P 2n-3 P 2n-2and in the same direction as P1P2, and P 2n-2 =P 2n When P 2n-2 ≠P 2n When the welding overlap surface is judged to be not in contact, the process ends.

[0146] Example 3

[0147] like Figure 2 to Figure 4 As shown, this embodiment takes two-layer welding as a specific example and briefly describes the process.

[0148] K800222860vsK800234960:

[0149] P1(2002.21,-521.282,106.903)

[0150] P2(2002.21,-520.094,106.736)

[0151] P3(2002.21,-520.094,106.736)

[0152] P4(2002.21,-518.905,106.569)

[0153] Vector P1P2 = (x1, y1, z1) = (0, 1.188, -0.167)

[0154] Vector P3P4 = (x2, y2, z2) = (0, 1.189, -0.167)

[0155] vector

[0156] vector

[0157] Vector P1P2 normalized = (0, 0.990263762, -0.139203744)

[0158] Vector P3P4 normalized = (0, 0.991097317, -0.139203744)

[0159] Dot product = 0 × 0 + 0.990263762 × 0.991097317 + -0.139203744 × -0.139203744

[0160] =1.000825≈1

[0161] The dot product is within the allowable error range, so the vector P1P2 is in the same direction as the vector P3P4, and the coordinate values ​​of points P2 and P4 are within the allowable error range, so it is determined that the two layers are welded together.

[0162] Example 4

[0163] like Figure 5 As shown, the present invention provides a system for automatically checking the fit of a welding overlap surface, comprising:

[0164] The solder joint information acquisition module is used to retrieve the solder joint file and extract the part information. Specifically, the module obtains the part number information by reading the geometry set name (such as "K1vsK2vsK3") in the solder joint file, and stores the extracted part numbers in sequence.

[0165] The normal generation module is used to generate the normal lines of each part surface passing through the center of the solder joint. The module first determines the coordinates of the solder joint center P0, then calculates the normal direction vector for each part surface, and generates the normal line equation passing through the center P0. For example, for part K1, generate line L1; for part K2, generate line L2, and so on.

[0166] The intersection calculation module is used to calculate the intersection of the normal line and the part. This module calculates the two intersections of each normal line and its corresponding part by solving the normal line equation and the corresponding part surface equation. For example, the intersections of line L1 and part K1 are P1 and P2, the intersections of line L2 and part K2 are P3 and P4, and so on to obtain the coordinates of all intersections.

[0167] The fit detection module is used to perform fit detection.

[0168] In some optional embodiments of the present invention, the fit detection module includes:

[0169] The unique point statistics unit is used to count the number of intersections with different coordinates. The unique point statistics unit compares all the intersection coordinates in pairs and counts the number of unique points with different coordinates. When x = 2, it means that there may be a fitting path, and the subsequent detection continues; when x ≠ 2, it is directly determined that the welding overlap surface is not fitted.

[0170] The coordinate exchange unit is used to exchange the intersection coordinate values. The coordinate exchange unit performs a reordering operation of the intersection coordinates. Specifically:

[0171] A unique point (denoted as P a ) and P1, and a The coordinate value of another intersection point belonging to the same part is exchanged with P2;

[0172] Another unique point (denoted as P b ) and P 2n Exchange, and at the same time b The coordinate value of another intersection point of the same part is the same as P(2n-1) exchange;

[0173] Subsequently, similar coordinate exchange operations are continued based on the equality relationship of the points.

[0174] Vector calculation unit, used to calculate and compare vectors between adjacent intersection points. Specific operations include:

[0175] Calculate vector P1P2 and vector P 2n-1 P 2n ;

[0176] Normalize the vector;

[0177] Calculate the dot product of unit vectors to determine whether the vectors are in the same direction;

[0178] If a point P with the same coordinates as P2 is found c , then calculate the new vector P3P4 and continue to judge the same direction.

[0179] The fit determination unit is used to determine the fit degree based on the vector isotropy and point coincidence. The fit determination unit makes a final determination based on the vector isotropy and point coincidence. The determination criteria are:

[0180] All adjacent vectors must be in the same direction (the absolute value of the unit vector dot product is equal to 1 within the error range);

[0181] Adjacent points except the start and end points must coincide (coordinate differences are within the preset tolerance).

[0182] In some optional embodiments of the present invention, the system further comprises:

[0183] The data storage module is used to store solder joint information, part information and test results; it is used to store solder joint file content, extracted part information, calculated intersection coordinates, vector calculation results and final test results. This module uses structured data storage to facilitate rapid retrieval and update of data.

[0184] The parameter setting module is used to set the coordinate tolerance and vector error range. This module includes:

[0185] Coordinate tolerance setting unit: used to set the allowable range of coordinate error when judging point coincidence;

[0186] Vector error setting unit: used to set the allowable range of dot product error when judging whether the vectors are in the same direction;

[0187] Parameter verification unit: used to check whether the set parameters are within a reasonable range to ensure the reliability of the test results.

[0188] The result output module is used to generate the test report, including: basic information of the solder joint; the fitting relationship between parts; the specific reasons for the non-fitting situation; and the test parameter configuration information.

[0189] Through the collaborative work of the above modules, the system can efficiently and accurately complete the automatic detection of the weld lap joint fit, significantly improving the detection efficiency and reducing the workload of manual inspection. At the same time, the modular design of the system makes the coupling degree between the functional units low and the maintainability good, which is convenient for subsequent functional expansion and optimization and upgrading.

[0190] Example 5

[0191] like Figure 6 As shown, the present invention provides an electronic device, including a processor 1, a communication interface 2, a memory 3 and a communication bus 4, wherein the processor 1, the communication interface 2, and the memory 3 communicate with each other through the communication bus 4; the memory 4 is used to store computer programs; the processor 1 is used to implement the method of automatically checking the fit of the welding lap surface described in Example 1 and Example 2 when executing the program stored in the memory 3.

[0192] The processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0193] The memory may include a random access memory (Random Access Memory, RAM), and may also include a non-volatile memory (Non-Volatile Memory, NVM), such as at least one disk memory.

[0194] The memory may be a volatile memory, such as a random-access memory (RAM); the memory may also be a non-volatile memory, such as a read-only memory, a flash memory, a hard disk drive (HDD) or a solid-state drive (SSD), or the memory is any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory may be a combination of the above memories.

[0195] Those skilled in the art will readily appreciate that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, combinations, replacements, improvements, etc. made within the spirit and principles of the present invention are included within the protection scope of the present invention.

Claims

1. A method for automatically checking the fit of a welded lap joint, characterized in that: The following steps are involved: Retrieve solder joint files and extract part number information; Draw the normal line of each part surface through the center of the welding point sphere; Calculate the intersection point of each normal line with the corresponding part; The obtained intersection points are tested for fit.

2. The method for automatically checking the fit of the welding lap surface according to claim 1, characterized in that: The fit test includes: Compare the coordinates of the intersection points pairwise to determine the number x of unique points whose coordinates are not equal to each other; When x=2, coordinate exchange and fit verification are performed; When x≠2, it is determined that the welding lap surfaces are not in contact.

3. The method for automatically checking the fit of the welding lap surface according to claim 2, characterized in that: The coordinate exchange and fit verification include: Take one of the unique points as the path starting point and the other unique point as the path end point, and exchange the coordinates of the intersection points so that the path starting point is at P1 and the path end point is at P 2n Location; Check whether adjacent intersection points overlap in sequence; Calculate the vectors between adjacent intersection points and determine whether they are in the same direction; When all vectors are in the same direction and adjacent intersection points coincide, the weld lap surfaces are considered to be in close contact.

4. The method for automatically checking the fit of the welded lap joint according to claim 3, characterized in that: The coordinate exchange includes: Let a unique point be P a , and another unique point is denoted as P b ; P a The coordinate values ​​of P1 are exchanged with the coordinate values ​​of P a The coordinate values ​​of another intersection point belonging to the same part are exchanged with the coordinate values ​​of P2; P b The coordinate values ​​of P 2n The coordinate values ​​of P b The coordinate value of another intersection point belonging to the same part is the same as P 2n-1 The coordinate values ​​of .

5. The method for automatically checking the fit of the welding lap joint according to claim 4, characterized in that: The fit verification includes: Calculate vector P1P2 and vector P 2n-1 P 2n ; When vector P1P2 and vector P 2n-1 P 2n When the directions are different, it is determined that the welding lap surfaces are not fitted; When vector P1P2 and vector P 2n-1 P 2n When in the same direction, check whether the coordinate values ​​of P2 and subsequent intersection points are equal.

6. The method for automatically checking the fit of a welded lap joint according to claim 5, characterized in that: When a point P with the same coordinates as P2 is found c When P c The coordinate values ​​of are exchanged with those of P3; Will be with P c The coordinate values ​​of another intersection point belonging to the same part are exchanged with the coordinate values ​​of P4; Calculate vector P3P4; When the vector P3P4 and the vector P1P2 are in different directions, it is determined that the welding lap surface is not fitted; When vector P3P4 and vector P1P2 have the same direction, repeat the above operation.

7. The method for automatically checking the fit of the welded lap joint according to claim 5 or 6, characterized in that: When you find a 2n The points with the same coordinate values ​​are used to determine whether the weld overlap surfaces are aligned; if all points are compared but no points with P are found, 2n The equal points determine that the welding lap surfaces do not fit well.

8. The method for automatically checking the degree of fit of a welded lap joint according to claim 7, characterized in that: The coordinates of the points are equal when the differences of the coordinate components are within the preset tolerance range.

9. The method for automatically checking the degree of fit of a welded lap joint according to claim 5 or 6, characterized in that: Vectors are in the same direction when the absolute value of the dot product of the unit vectors is equal to 1 within the error range.

10. A system for automatically checking the degree of fit of a welded lap joint using the method of any one of claims 1 to 9, the system comprising: Solder point information acquisition module, used to retrieve solder point files and extract part information; Normal generation module, used to generate the normal lines of each part surface passing through the center of the welding point; Intersection calculation module, used to calculate the intersection of normal lines and parts; The fit detection module is used to perform fit detection.

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