A welding machine control method based on machine vision

Abstract

The present invention relates to the technical field of welding machine control, and discloses a welding machine control method based on machine vision, including: pre-welding simulation experiment, measuring deformation length and height, and calculating span-to-height ratio. Adjust the highest point of deformation to the standard position, and use a visual sensor to measure the distance between the left and right deformations and the standard position. Compare the distance threshold to decide whether to make a secondary adjustment. Record the relationship between the span-to-height ratio and the secondary adjustment. After the adjustment, welding is completed, and the position of the pressure holding point is obtained. Determine the total pressure holding time according to the weld bearing capacity and natural cooling time. Compare the total pressure holding time with the span-to-height ratio, formulate an adjustment strategy and pressure holding operation time, and assist in welding workpieces. Through simulation experiments, when deformation is encountered later, the adjustment strategy and pressure holding time are quickly determined, the deformation is quickly and effectively adjusted, the time consumed by deformation during welding is reduced, and the pressure holding operation of the deformation is performed so that the weld will not be torn due to the rebound of the deformation after welding, thereby improving the welding quality.

Description

Technical Field

[0001] The invention relates to the technical field of welding machine control, and in particular to a welding machine control method based on machine vision. Background Art

[0002] The machine vision inspection system uses image acquisition hardware to convert the inspected target into an image signal, which is then transmitted to a dedicated image processing system. Based on pixel distribution, brightness, color and other information, the signal is converted into a digital signal. The image processing system performs various operations on these signals to extract the target's features, such as area, quantity, position, and length, and then outputs the results based on the preset tolerance and other conditions, including size, angle, number, etc., to achieve automatic recognition. Machine vision is tireless and has a high tracking speed and resolution accuracy. In some dangerous working environments that are not suitable for manual operations or where manual vision is difficult to meet the requirements, machine vision is often used to replace manual vision, greatly improving production efficiency and the degree of automation of production. Therefore, machine vision technology has been widely used in many fields.

[0003] Automated production requires reducing manpower, improving product consistency, improving product quality, being more suitable for mass production, reducing production costs, and improving production efficiency. However, during manual welding, it is difficult to maintain the stability and consistency of welding work for a long time due to the influence of objective and subjective factors such as technical level, fatigue level, sense of responsibility, and physiological limits. Welding machines can solve the above problems and meet the requirements of welding automation to a large extent. Therefore, welding machines have been widely used in various welding production processes.

[0004] At present, when a more common welding machine encounters deformation on the welding line of a workpiece during welding, the welding of the workpiece is generally stopped directly, and the deformation is adjusted after manual intervention before welding the workpiece again. During the welding process, no deformation adjustment operation is involved, which increases the total time for welding a workpiece to a certain extent and increases the production time cost. Summary of the invention

[0005] The present invention provides a welding machine control method based on machine vision, which helps to solve the problem mentioned in the above background technology that during the welding process, there is no adjustment operation on the deformation, which increases the production time cost.

[0006] The present invention provides the following technical solution: a welding machine control method based on machine vision, comprising:

[0007] Conduct simulation experiments before welding to obtain the length and height of deformation;

[0008] Get the ratio of the length to the height of the deformation, recorded as the span-to-height ratio;

[0009] Obtain the highest point of deformation, record it as the adjustment point, apply pressure to the adjustment point, and reset the adjustment point to the standard position of the welding line;

[0010] When the adjustment point is reset to the standard position of the welding line, the longest distance between the left deformation and the right deformation and the standard position of the welding line is obtained by the visual sensor;

[0011] Set a distance threshold, compare the longest distance with the distance threshold, and determine whether to perform secondary adjustment based on the comparison result;

[0012] Record the span-to-height ratio of deformation in the simulation experiment to determine whether deformations with different span-to-height ratios require secondary adjustments;

[0013] After the adjustment is completed, welding is performed to obtain the position of the pressure holding point after welding;

[0014] Perform pressure holding operation on the pressure holding point, and obtain the total pressure holding operation time according to the maximum tensile force that the weld can bear under different natural cooling times;

[0015] Match the total duration of the pressure holding operation with the span-to-height ratio of the deformation to obtain the total duration of the pressure holding operation required for deformations with different span-to-height ratios;

[0016] Weld the workpieces to be welded, obtain the deformation encountered during the welding process, and determine the adjustment strategy based on the span-to-height ratio of the deformation;

[0017] Perform a packing operation on the adjusted deformation, and determine the total packing operation duration according to the span-to-height ratio of the deformation;

[0018] By adjusting the strategy and maintaining pressure, the welding of the workpiece is assisted.

[0019] Optionally, the ratio of the length to the height of the obtained deformation is recorded as the span-to-height ratio, which is specifically:

[0020] For the deformation encountered during welding, this deformation is recorded as deformation No. 1;

[0021] Obtain the starting point and the ending point of deformation No. 1, connect the starting point and the ending point of deformation No. 1, and obtain a line segment, which is recorded as line segment No. 1;

[0022] Get the length of line segment 1 as the length of deformation 1;

[0023] Get the highest point of deformation No. 1, and get the vertical distance from this point to line segment No. 1 as the height of deformation No. 1;

[0024] Calculate the ratio of the length to the height of deformation No. 1 as the span-to-height ratio of deformation No. 1.

[0025] Optionally, obtaining the highest point of deformation, recording it as an adjustment point, applying pressure to the adjustment point to reset the adjustment point to a standard position of the welding wire, specifically includes:

[0026] The position of the highest point of deformation is obtained through the visual sensor, and this position is named as the adjustment point;

[0027] Obtain the starting point and the ending point of the deformation, draw a straight line through the starting point and the ending point parallel to the welding line, and use the position of the straight line as the standard position of the welding line;

[0028] Point the adjustment point vertically to the direction of the standard position of the welding line as the adjustment direction;

[0029] At the location of the adjustment point, apply pressure in the adjustment direction to make the adjustment point coincide with the standard position of the welding wire.

[0030] Optionally, when the adjustment point is reset to the standard position of the welding line, the longest distances between the left deformation and the right deformation and the standard position of the welding line are respectively obtained by a visual sensor, specifically:

[0031] When the adjustment point coincides with the standard position of the welding line, a deformation is generated on both sides of the adjustment point. According to the direction of welding, the deformation on both sides of the adjustment point are recorded as left deformation and right deformation respectively.

[0032] The highest points of the left deformation and the right deformation are obtained respectively through the visual sensor;

[0033] Get the vertical distance from the highest point of left deformation to the standard position of the welding line, which is recorded as the left distance;

[0034] Get the vertical distance from the highest point of right deformation to the standard position of the welding line, and record it as the right distance.

[0035] Optionally, the distance threshold is set, the longest distance is compared with the distance threshold, and whether to perform secondary adjustment is determined according to the comparison result, specifically:

[0036] Set the distance threshold to A;

[0037] Compare the left distance and the right distance with the distance threshold A respectively;

[0038] If the left distance is less than or equal to A, and the right distance is less than or equal to A, it is considered that the welding requirements are met and no secondary adjustment is made;

[0039] If the left distance or the right distance is greater than A, the left deformation or the right deformation is adjusted twice;

[0040] If the left distance is greater than A, obtain the highest point of the left deformation and record it as the left adjustment point;

[0041] Point the left adjustment point vertically to the direction of the standard position of the welding line as the left adjustment direction;

[0042] At the left adjustment point, apply pressure in the left adjustment direction to make the left adjustment point coincide with the standard position of the welding line to complete the adjustment of the left deformation;

[0043] If the right distance is greater than A, obtain the highest point of the right deformation and record it as the right adjustment point;

[0044] Point the right adjustment point vertically to the direction of the welding line standard position as the right adjustment direction;

[0045] At the right adjustment point, apply pressure in the right adjustment direction to make the right adjustment point coincide with the standard position of the welding line to complete the adjustment of the right deformation;

[0046] By completing the adjustment of the left deformation and the right deformation, the secondary adjustment of the deformation is completed.

[0047] Optionally, performing welding after completing the adjustment and obtaining the position of the pressure holding point after welding includes:

[0048] When no secondary adjustment is required, there is a pressure holding point;

[0049] Get the starting point and ending point of the deformation;

[0050] Obtain the total length of the welding line track from the adjustment point to the deformation starting point, recorded as B;

[0051] At the standard position of the welding line, point from the deformation starting point to the deformation ending point, and obtain the point with a distance B from the deformation starting point, which is recorded as the middle pressure holding point;

[0052] The middle pressure holding point is used as a pressure holding point after welding.

[0053] Optionally, the step of performing welding after the adjustment is completed and obtaining the position of the pressure holding point after welding further includes:

[0054] If secondary adjustment is required, apply pressure to the adjustment point to reset the adjustment point to the standard position of the welding line, forming left deformation and right deformation;

[0055] The left deformation starts at the deformation start point and ends at the deformation adjustment point, and the right deformation starts at the deformation adjustment point and ends at the deformation end point.

[0056] Get the total length of the welding line track from the left adjustment point to the starting point, recorded as C;

[0057] Get the total length of the welding line track from the right adjustment point to the adjustment point, recorded as D;

[0058] When a secondary adjustment is required and the left and right deformations need to be adjusted, there are three pressure holding points;

[0059] At the standard position of the welding line, point the starting point in the direction of the adjustment point, and obtain the point with a distance C from the starting point, which is recorded as the left pressure holding point;

[0060] At the standard position of the welding line, point from the starting point to the ending point, and obtain the point with a distance of B+C from the starting point, which is recorded as the middle pressure-maintaining point;

[0061] At the standard position of the welding line, point the adjustment point in the direction of the end point, and obtain the point with a distance of B+C+D from the starting point, which is recorded as the right pressure holding point;

[0062] The left pressure holding point, the middle pressure holding point and the right pressure holding point are used as the three pressure holding points after welding;

[0063] When a secondary adjustment is required, but only the left deformation needs to be adjusted, there are two pressure holding points;

[0064] At the standard position of the welding line, point the starting point in the direction of the adjustment point, and obtain the point with a distance C from the starting point, which is recorded as the left pressure holding point;

[0065] At the standard position of the welding line, point from the starting point to the ending point, and obtain the point with a distance of B+C from the starting point, which is recorded as the middle pressure-maintaining point;

[0066] The left pressure holding point and the middle pressure holding point are used as the two pressure holding points after welding;

[0067] When a secondary adjustment is required, but only the right deformation needs to be adjusted, there are two pressure holding points;

[0068] At the standard position of the welding line, point from the starting point to the ending point, and obtain the point with a distance B from the starting point, which is recorded as the middle pressure-maintaining point;

[0069] At the standard position of the welding line, adjust the point to point to the end point, and obtain the point with a distance of B+D from the starting point, which is recorded as the right pressure holding point.

[0070] The middle pressure holding point and the right pressure holding point are used as the two pressure holding points after welding.

[0071] Optionally, the pressure holding point is subjected to a pressure holding operation, and the total duration of the pressure holding operation is obtained according to the maximum tensile force that the weld can bear under different natural cooling times, specifically:

[0072] After welding is completed, the maximum tensile force that the weld can withstand is tested every 1S to obtain the maximum tensile force that the weld can withstand under different natural cooling times;

[0073] After welding is completed, the span-to-height ratio of the deformation is obtained, and pressure is applied to the pressure holding point of the deformation;

[0074] When the distance between the pressure holding point and the standard position of the welding line reaches the distance threshold, the pressure value of the current pressure holding device is obtained, which is recorded as F;

[0075] Match the deformation span-to-height ratio with the deformation F to obtain the deformation F value under different span-to-height ratios;

[0076] According to the maximum tensile force that the weld can bear under different natural cooling times, the natural cooling time of the weld when the maximum tensile force that the weld can withstand is F is obtained, and this time is used as the total pressure holding operation time for deformation.

[0077] The present invention has the following beneficial effects:

[0078] 1. The use of visual sensors can more accurately obtain the position of the highest point of deformation, so that the distance between the deformation and the standard position of the welding wire can be obtained with high precision to ensure that the judgment on whether the deformation should be adjusted again is accurate.

[0079] 2. The setting of the distance threshold allows a certain error between the welding wire and the standard position of the welding wire, so as to avoid excessive adjustment time and increase production costs due to excessive but unnecessary precision requirements in the actual production process.

[0080] 3. Through the pressure-maintaining operation, pressure is applied to the deformation and maintained for a certain period of time to reset and fix the deformation as much as possible, reducing the rebound of the deformation after the pressure is stopped; at the same time, the pressure-maintaining operation is used to prevent the weld from being torn due to the rebound of the deformation after welding is completed.

[0081] 4. Through simulation experiments, the relationship between the span-to-height ratio of deformation and the number of adjustments required and the duration of the pressure holding operation is determined, so that when deformation occurs in the subsequent welding process, the appropriate adjustment strategy and sufficient pressure holding time can be quickly determined to achieve rapid and effective adjustment of deformation and improve welding quality and efficiency.

[0082] 5. Through the deformation adjustment strategy and pressure holding operation, the deformation encountered in the welding process can be adjusted quickly and effectively, reducing the time consumed by deformation during welding, making the welding process smoother. At the same time, the pressure holding operation of the deformation prevents the weld from being torn due to the rebound of the deformation, thereby improving the overall welding quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] Figure 1 It is a schematic diagram of deformation points of the present invention.

[0084] Figure 2 It is a schematic diagram of the left deformation and right deformation points of the present invention. DETAILED DESCRIPTION

[0085] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the 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.

[0086] Embodiment, a welding machine control method based on machine vision, comprising:

[0087] Conduct simulation experiments before welding to obtain the length and height of deformation;

[0088] Get the ratio of the length to the height of the deformation, recorded as the span-to-height ratio;

[0089] Obtain the highest point of deformation, record it as the adjustment point, apply pressure to the adjustment point, and reset the adjustment point to the standard position of the welding line;

[0090] When the adjustment point is reset to the standard position of the welding line, the longest distances between the left deformation and the right deformation and the standard position of the welding line are respectively obtained through the visual sensor; the use of the visual sensor can more accurately obtain the position of the highest point of the deformation, so that the distance between the deformation and the standard position of the welding line can be obtained with high precision, so as to ensure that the judgment on whether the deformation should be adjusted again is accurate.

[0091] Set the distance threshold, compare the longest distance with the distance threshold, and determine whether to perform secondary adjustment based on the comparison result; the setting of the distance threshold allows a certain error between the welding wire and the welding wire standard position, avoiding excessive adjustment time and increased production costs due to excessive but unnecessary precision requirements in the actual production process.

[0092] Record the span-to-height ratio of deformation in the simulation experiment to determine whether deformations with different span-to-height ratios require secondary adjustments;

[0093] After the adjustment is completed, welding is performed to obtain the position of the pressure holding point after welding;

[0094] The pressure holding point is operated to maintain pressure, and the total duration of the pressure holding operation is obtained according to the maximum tensile force that the weld can bear under different natural cooling times. Through the pressure holding operation, pressure is applied to the deformation and maintained for a certain period of time to reset and fix the deformation as much as possible, thereby reducing the rebound of the deformation after the pressure is stopped. At the same time, the pressure holding operation is performed to prevent the weld from being torn due to the rebound of the deformation after the welding is completed.

[0095] Match the total duration of the pressure holding operation with the span-to-height ratio of the deformation to obtain the total duration of the pressure holding operation required for deformations with different span-to-height ratios;

[0096] Weld the workpiece that needs to be welded, obtain the deformation encountered in the welding process, and determine the adjustment strategy based on the span-to-height ratio of the deformation; through simulation experiments, determine the relationship between the span-to-height ratio of the deformation and the number of times required for adjustment and the duration of the pressure holding operation, so that in the subsequent welding process, when deformation is encountered, quickly determine the appropriate adjustment strategy and sufficient pressure holding time, so as to achieve rapid and effective adjustment of the deformation and improve welding quality and efficiency.

[0097] Perform a packing operation on the adjusted deformation, and determine the total packing operation duration according to the span-to-height ratio of the deformation;

[0098] Through adjustment strategies and pressure-holding operations, the workpiece welding is assisted. Through the deformation adjustment strategy and pressure-holding operation, the deformation encountered during the welding process is adjusted quickly and effectively, reducing the time spent on deformation during welding, making the welding process smoother, and at the same time, the pressure-holding operation of the deformation prevents the weld from being torn due to the rebound of the deformation, thereby improving the overall welding quality.

[0099] The ratio of the length to the height of the obtained deformation is recorded as the span-to-height ratio, which is specifically:

[0100] For the deformation encountered during welding, this deformation is recorded as deformation No. 1;

[0101] Obtain the starting point and the ending point of deformation No. 1, connect the starting point and the ending point of deformation No. 1, and obtain a line segment, which is recorded as line segment No. 1;

[0102] Get the length of line segment 1 as the length of deformation 1;

[0103] Get the highest point of deformation No. 1, and get the vertical distance from this point to line segment No. 1 as the height of deformation No. 1;

[0104] Calculate the ratio of the length to the height of deformation No. 1 as the span-to-height ratio of deformation No. 1.

[0105] The highest point of the deformation is obtained, recorded as the adjustment point, and pressure is applied to the adjustment point to reset the adjustment point to the standard position of the welding wire, specifically including:

[0106] The position of the highest point of deformation is obtained through the visual sensor, and this position is named as the adjustment point;

[0107] Reference Figure 1 , obtain the starting point and the ending point of the deformation, draw a straight line parallel to the welding line through the starting point and the ending point, and take the position of the straight line as the standard position of the welding line;

[0108] Point the adjustment point vertically to the direction of the standard position of the welding line as the adjustment direction;

[0109] At the location of the adjustment point, apply pressure in the adjustment direction to make the adjustment point coincide with the standard position of the welding wire.

[0110] When the adjustment point is reset to the standard position of the welding line, the longest distances between the left deformation and the right deformation and the standard position of the welding line are respectively obtained by the visual sensor, specifically:

[0111] When the adjustment point coincides with the standard position of the welding line, a deformation is generated on both sides of the adjustment point. According to the direction of welding, the deformation on both sides of the adjustment point are recorded as left deformation and right deformation respectively.

[0112] The highest points of the left deformation and the right deformation are obtained respectively through the visual sensor;

[0113] Get the vertical distance from the highest point of left deformation to the standard position of the welding line, which is recorded as the left distance;

[0114] Get the vertical distance from the highest point of right deformation to the standard position of the welding line, and record it as the right distance.

[0115] The distance threshold is set, the longest distance is compared with the distance threshold, and whether to perform secondary adjustment is determined according to the comparison result, specifically:

[0116] Set the distance threshold to A. The distance threshold reflects the maximum distance between the deformation on both sides of the adjustment point and the standard position of the welding line after adjustment. The smaller the A value, the closer the deformation is to the standard position of the welding line. When the A value is set to 0, the deformation is required to completely overlap with the standard position of the welding line.

[0117] Compare the left distance and the right distance with the distance threshold A respectively;

[0118] If the left distance is less than or equal to A, and the right distance is less than or equal to A, it is considered that the welding requirements are met and no secondary adjustment is made;

[0119] If the left distance or the right distance is greater than A, it means that the left deformation or the right deformation does not meet the welding requirements and needs to be adjusted again.

[0120] If the left distance is greater than A, it means that the left deformation does not meet the welding requirements, and it is necessary to obtain the highest point of the left deformation and record it as the left adjustment point;

[0121] Point the left adjustment point vertically to the direction of the standard position of the welding line as the left adjustment direction;

[0122] At the left adjustment point, apply pressure in the left adjustment direction to make the left adjustment point coincide with the standard position of the welding line to complete the adjustment of the left deformation;

[0123] If the right distance is greater than A, it means that the right deformation does not meet the welding requirements, and it is necessary to obtain the highest point of the right deformation, which is recorded as the right adjustment point;

[0124] Point the right adjustment point vertically to the direction of the welding line standard position as the right adjustment direction;

[0125] At the right adjustment point, apply pressure in the right adjustment direction to make the right adjustment point coincide with the standard position of the welding line to complete the adjustment of the right deformation;

[0126] By completing the adjustment of the left deformation and the right deformation, the secondary adjustment of the deformation is completed.

[0127] After the adjustment is completed, welding is performed to obtain the position of the pressure holding point after welding. The position of the pressure holding point is the position of the adjustment point on the standard position of the welding line after adjustment. Therefore, the number of pressure holding points is the same as the number of adjustment points, including:

[0128] When secondary adjustment is not required, only one adjustment of the deformation is required. There is only one adjustment point during the adjustment, so there is only one pressure holding point after the adjustment.

[0129] Reference Figure 1 , obtain the starting point and ending point of the deformation;

[0130] Obtain the total length of the welding line track from the adjustment point to the deformation starting point, recorded as B;

[0131] At the standard position of the welding line, point from the deformation starting point to the deformation ending point, and obtain the point with a distance B from the deformation starting point, which is recorded as the middle pressure holding point;

[0132] The middle pressure holding point is used as a pressure holding point after welding.

[0133] After the adjustment is completed, welding is performed to obtain the position of the pressure holding point after welding, and further includes:

[0134] If secondary adjustment is required, apply pressure to the adjustment point to reset the adjustment point to the standard position of the welding line, forming left deformation and right deformation;

[0135] Reference Figure 2 , where the left deformation starts at the deformation start point and ends at the deformation adjustment point, and the right deformation starts at the deformation adjustment point and ends at the deformation end point;

[0136] Get the total length of the welding line track from the left adjustment point to the starting point, recorded as C;

[0137] Get the total length of the welding line track from the right adjustment point to the adjustment point, recorded as D;

[0138] When a secondary adjustment is required, and the left deformation and the right deformation need to be adjusted, the deformation needs to be adjusted once. After the deformation adjustment is completed, the left deformation and the right deformation formed by the first adjustment need to be adjusted separately. There are three adjustment points in the whole adjustment process, so there are three pressure holding points after the adjustment is completed.

[0139] At the standard position of the welding line, point the starting point in the direction of the adjustment point, and obtain the point with a distance C from the starting point, which is recorded as the left pressure holding point;

[0140] At the standard position of the welding line, point from the starting point to the ending point, and obtain the point with a distance of B+C from the starting point, which is recorded as the middle pressure-maintaining point;

[0141] At the standard position of the welding line, point the adjustment point in the direction of the end point, and obtain the point with a distance of B+C+D from the starting point, which is recorded as the right pressure holding point;

[0142] The left pressure holding point, the middle pressure holding point and the right pressure holding point are used as the three pressure holding points after welding;

[0143] When a secondary adjustment is required, but only the left deformation needs to be adjusted, the deformation needs to be adjusted once. After the deformation adjustment is completed, the left deformation also needs to be adjusted. There are two adjustment points in the whole adjustment process, so there are two pressure holding points after the adjustment is completed;

[0144] At the standard position of the welding line, point the starting point in the direction of the adjustment point, and obtain the point with a distance C from the starting point, which is recorded as the left pressure holding point;

[0145] At the standard position of the welding line, point from the starting point to the ending point, and obtain the point with a distance of B+C from the starting point, which is recorded as the middle pressure-maintaining point;

[0146] The left pressure holding point and the middle pressure holding point are used as the two pressure holding points after welding;

[0147] When a secondary adjustment is required, but only the right deformation needs to be adjusted, the deformation needs to be adjusted once. After the deformation adjustment is completed, the right deformation also needs to be adjusted. There are two adjustment points in the whole adjustment process, so there are two pressure holding points after the adjustment is completed;

[0148] At the standard position of the welding line, point from the starting point to the ending point, and obtain the point with a distance B from the starting point, which is recorded as the middle pressure-maintaining point;

[0149] At the standard position of the welding line, adjust the point to point to the end point, and obtain the point with a distance of B+D from the starting point, which is recorded as the right pressure holding point.

[0150] The middle pressure holding point and the right pressure holding point are used as the two pressure holding points after welding.

[0151] The pressure holding operation is performed on the pressure holding point, and the total duration of the pressure holding operation is obtained according to the maximum tensile force that the weld can bear under different natural cooling times, specifically:

[0152] After welding is completed, the maximum tensile force that the weld can withstand is tested every 1S to obtain the maximum tensile force that the weld can withstand under different natural cooling times; after welding is completed, as time goes by, the weld gradually cools down, the hardness increases, and the maximum tensile force that the weld can withstand also gradually increases;

[0153] After welding is completed, the span-to-height ratio of the deformation is obtained, and pressure is applied to the pressure holding point of the deformation;

[0154] When the distance between the pressure holding point and the standard position of the welding line reaches the distance threshold, it means that the welding requirements have been met, and the pressure value of the current pressure holding device is obtained, which is recorded as F. The value of F can represent the pulling force of the current deformation on the weld.

[0155] Match the deformation span-to-height ratio with the deformation F to obtain the deformation F value under different span-to-height ratios;

[0156] According to the maximum tensile force that the weld can withstand under different natural cooling times, the natural cooling time of the weld is obtained when the maximum tensile force that the weld can withstand is F. This time is used as the total pressure holding operation time for deformation. After the weld has been cooled for this time, the maximum tensile force that can be borne by the weld has exceeded the tensile force generated by the deformation rebound. At this time, the weld will not be torn due to the tensile force of the deformation.

[0157] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0158] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A welding machine control method based on machine vision, characterized in that: include: Conduct simulation experiments before welding to obtain the length and height of deformation; Get the ratio of the length to the height of the deformation, recorded as the span-to-height ratio; Obtain the highest point of deformation, record it as the adjustment point, apply pressure to the adjustment point, and reset the adjustment point to the standard position of the welding line; When the adjustment point is reset to the standard position of the welding line, the longest distance between the left deformation and the right deformation and the standard position of the welding line is obtained by the visual sensor; Set a distance threshold, compare the longest distance with the distance threshold, and determine whether to perform secondary adjustment based on the comparison result; Record the span-to-height ratio of deformation in the simulation experiment to determine whether deformations with different span-to-height ratios require secondary adjustments; After the adjustment is completed, welding is performed to obtain the position of the pressure holding point after welding; The pressure holding point is subjected to pressure holding operation, and the total pressure holding operation time is obtained according to the maximum tensile force that the weld can bear under different natural cooling times, which is: After welding is completed, the maximum tensile force that the weld can withstand is tested every 1S to obtain the maximum tensile force that the weld can withstand under different natural cooling times; After welding is completed, the span-to-height ratio of the deformation is obtained, and pressure is applied to the pressure holding point of the deformation; When the distance between the pressure holding point and the standard position of the welding line reaches the distance threshold, the pressure value of the current pressure holding device is obtained, which is recorded as F; Match the deformation span-to-height ratio with the deformation F to obtain the deformation F value under different span-to-height ratios; According to the maximum tensile force that the weld can bear under different natural cooling times, the natural cooling time of the weld when the maximum tensile force that the weld can bear is F is obtained, and this time is used as the total pressure holding operation time for deformation; Match the total duration of the pressure holding operation with the span-to-height ratio of the deformation to obtain the total duration of the pressure holding operation required for deformations with different span-to-height ratios; Weld the workpieces to be welded, obtain the deformation encountered during the welding process, and determine the adjustment strategy based on the span-to-height ratio of the deformation; Perform a packing operation on the adjusted deformation, and determine the total packing operation duration according to the span-to-height ratio of the deformation; By adjusting the strategy and maintaining pressure, the welding of the workpiece is assisted.

2. A welding machine control method based on machine vision according to claim 1, characterized in that: The ratio of the length to the height of the obtained deformation is recorded as the span-to-height ratio, which is specifically: For the deformation encountered during welding, this deformation is recorded as deformation No. 1; Obtain the starting point and the ending point of deformation No. 1, connect the starting point and the ending point of deformation No. 1, and obtain a line segment, which is recorded as line segment No. 1; Get the length of line segment 1 as the length of deformation 1; Get the highest point of deformation No. 1, and get the vertical distance from this point to line segment No. 1 as the height of deformation No. 1; Calculate the ratio of the length to the height of deformation No. 1 as the span-to-height ratio of deformation No.

1.

3. A welding machine control method based on machine vision according to claim 1, characterized in that: The highest point of the deformation is obtained, recorded as the adjustment point, and pressure is applied to the adjustment point to reset the adjustment point to the standard position of the welding wire, specifically including: The position of the highest point of deformation is obtained through the visual sensor, and this position is named as the adjustment point; Obtain the starting point and the ending point of the deformation, draw a straight line through the starting point and the ending point parallel to the welding line, and use the position of the straight line as the standard position of the welding line; Point the adjustment point vertically to the direction of the standard position of the welding line as the adjustment direction; At the location of the adjustment point, apply pressure in the adjustment direction to make the adjustment point coincide with the standard position of the welding wire.

4. A welding machine control method based on machine vision according to claim 1, characterized in that: When the adjustment point is reset to the standard position of the welding line, the longest distances between the left deformation and the right deformation and the standard position of the welding line are respectively obtained by the visual sensor, specifically: When the adjustment point coincides with the standard position of the welding line, a deformation is generated on both sides of the adjustment point. According to the direction of welding, the deformation on both sides of the adjustment point are recorded as left deformation and right deformation respectively. The highest points of the left deformation and the right deformation are obtained respectively through the visual sensor; Get the vertical distance from the highest point of left deformation to the standard position of the welding line, which is recorded as the left distance; Get the vertical distance from the highest point of right deformation to the standard position of the welding line, and record it as the right distance.

5. A welding machine control method based on machine vision according to claim 4, characterized in that: The distance threshold is set, the longest distance is compared with the distance threshold, and whether to perform secondary adjustment is determined according to the comparison result, specifically: Set the distance threshold to A; Compare the left distance and the right distance with the distance threshold A respectively; If the left distance is less than or equal to A, and the right distance is less than or equal to A, it is considered that the welding requirements are met and no secondary adjustment is made; If the left distance or the right distance is greater than A, the left deformation or the right deformation is adjusted twice; If the left distance is greater than A, obtain the highest point of the left deformation and record it as the left adjustment point; Point the left adjustment point vertically to the direction of the standard position of the welding line as the left adjustment direction; At the left adjustment point, apply pressure in the left adjustment direction to make the left adjustment point coincide with the standard position of the welding line to complete the adjustment of the left deformation; If the right distance is greater than A, obtain the highest point of the right deformation and record it as the right adjustment point; Point the right adjustment point vertically to the direction of the welding line standard position as the right adjustment direction; At the right adjustment point, apply pressure in the right adjustment direction to make the right adjustment point coincide with the standard position of the welding line to complete the adjustment of the right deformation; By completing the adjustment of the left deformation and the right deformation, the secondary adjustment of the deformation is completed.

6. A welding machine control method based on machine vision according to claim 5, characterized in that: After the adjustment is completed, welding is performed to obtain the position of the pressure holding point after welding, including: When no secondary adjustment is required, there is a pressure holding point; Get the starting point and ending point of the deformation; Obtain the total length of the welding line track from the adjustment point to the deformation starting point, recorded as B; At the standard position of the welding line, point from the deformation starting point to the deformation ending point, and obtain the point with a distance B from the deformation starting point, which is recorded as the middle pressure holding point; The middle pressure holding point is used as a pressure holding point after welding.

7. A welding machine control method based on machine vision according to claim 6, characterized in that: After the adjustment is completed, welding is performed to obtain the position of the pressure holding point after welding, and further includes: If secondary adjustment is required, apply pressure to the adjustment point to reset the adjustment point to the standard position of the welding line, forming left deformation and right deformation; The left deformation starts at the deformation start point and ends at the deformation adjustment point, and the right deformation starts at the deformation adjustment point and ends at the deformation end point. Get the total length of the welding line track from the left adjustment point to the starting point, recorded as C; Get the total length of the welding line track from the right adjustment point to the adjustment point, recorded as D; When a secondary adjustment is required and the left and right deformations need to be adjusted, there are three pressure holding points; At the standard position of the welding line, point the starting point in the direction of the adjustment point, and obtain the point with a distance C from the starting point, which is recorded as the left pressure holding point; At the standard position of the welding line, point from the starting point to the ending point, and obtain the point with a distance of B+C from the starting point, which is recorded as the middle pressure-maintaining point; At the standard position of the welding line, point the adjustment point in the direction of the end point, and obtain the point with a distance of B+C+D from the starting point, which is recorded as the right pressure holding point; The left pressure holding point, the middle pressure holding point and the right pressure holding point are used as the three pressure holding points after welding; When a secondary adjustment is required, but only the left deformation needs to be adjusted, there are two pressure holding points; At the standard position of the welding line, point the starting point in the direction of the adjustment point, and obtain the point with a distance C from the starting point, which is recorded as the left pressure holding point; At the standard position of the welding line, point from the starting point to the ending point, and obtain the point with a distance of B+C from the starting point, which is recorded as the middle pressure-maintaining point; The left pressure holding point and the middle pressure holding point are used as the two pressure holding points after welding; When a secondary adjustment is required, but only the right deformation needs to be adjusted, there are two pressure holding points; At the standard position of the welding line, point from the starting point to the ending point, and obtain the point with a distance B from the starting point, which is recorded as the middle pressure-maintaining point; At the standard position of the welding line, adjust the point to point to the end point, and obtain the point with a distance of B+D from the starting point, which is recorded as the right pressure holding point. The middle pressure holding point and the right pressure holding point are used as the two pressure holding points after welding.

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