Welding track correction method and device

Abstract

The present invention discloses a welding trajectory correction method and device. The method obtains voltage information generated between each capacitive sensor and the weld bevel of a welded object in real time. Based on the structural parameters and voltage information of each capacitive sensor at the current moment, the plate spacing between each capacitive sensor and the weld bevel, as well as the sensor tilt angle, are determined. When all capacitive sensors are parallel to the weld bevel, the weld eccentricity and weld edge width of the welded object are determined based on the plate spacing and sensor tilt angles. The deviation difference between the trajectory center distance and the weld eccentricity between the welded objects is calculated. If the deviation difference is greater than a preset deviation threshold, the weld edge width is used as a constraint to plan a splicing trajectory, and the current welding trajectory of the welded object is corrected along the splicing trajectory. This method reduces the computational complexity of weld-related data without using a visual sensor, effectively improving the accuracy of welding trajectory correction for a welding robot.

Description

Technical Field

[0001] The present invention relates to the technical field of track correction, and in particular to a welding track correction method and device. Background Art

[0002] Metal welding is a common manufacturing method used to join two or more metal parts into a single, integrated component. Its development is a key indicator of a country's industrial and scientific and technological development. With the continuous advancement of science and technology, modern welding technology has evolved into an advanced manufacturing technique capable of permanently joining materials and ensuring the desired functionality of welded joints. Welding technology is widely used. Together with other methods such as metal machining, casting, and heat treatment, welding, a metalworking technique, has become a fundamental production method across various industries, including the automotive, shipbuilding, aerospace, petrochemical, and electronics sectors.

[0003] In welding technology, weld edge width detection and welding trajectory correction are important indicators for measuring its effectiveness. Existing technologies usually first determine the region of interest based on image grayscale information, then use the skeleton method to extract the center line of the structured light pattern for the front weld image, calculate the distorted position of the center line to identify the weld feature points; for the back weld image, use the texture energy template to filter the weld image to determine the weld area, then calculate the intersection of the weld area and the structured light stripes to identify the weld feature points; the identified feature points are corrected using sequence image information, and finally the weld width is calculated based on the feature points. Alternatively, the gap detection sensor is called, using a semiconductor laser as an auxiliary light source, a position sensitive element (PSD) as a receiving device, and a stepper motor to drive the sensor to perform a horizontal scan above the workpiece to obtain information on the butt weld width.

[0004] However, as the industrial landscape continues to modernize and automate, the requirements for welds are becoming increasingly stringent. When applied to certain metal welding scenarios, the high temperatures generated by the welding process prevent the use of infrared or laser ranging methods to maintain a constant distance between the welding head and the metal being welded. Furthermore, the use of vision sensors for weld seam detection and weld trajectory correction is computationally intensive and lacks real-time performance, resulting in low correction accuracy. Summary of the Invention

[0005] The present invention provides a welding trajectory correction method and device, which solves the technical problem that when the existing technology is applied in certain metal welding occasions, due to the high temperature and heat generated by the welding process, it is impossible to use infrared or laser ranging methods to maintain a constant distance between the welding head and the welded metal. At the same time, the use of visual sensors for welding object weld detection and welding trajectory correction has a large amount of calculation and poor real-time performance, which leads to low correction accuracy.

[0006] The present invention provides a welding trajectory correction method, which is applied to a processor in a correction device, wherein the processor is communicatively connected to multiple groups of capacitive sensors of the correction device, and the method includes:

[0007] Real-time acquisition of voltage information generated between each of the capacitive sensors and the weld bevel of the weld object;

[0008] Determining the plate spacing between each capacitive sensor and the weld bevel, and the sensor tilt angle according to the structural parameters of each capacitive sensor at a current moment and the voltage information;

[0009] When all the capacitive sensors are parallel to the weld bevel, determining the weld eccentricity and weld edge width of the welded object according to the plate spacing, the sensor inclination angle and the structural parameters;

[0010] Calculating the deviation difference between the center distance of the track between the welding objects and the eccentricity of the weld;

[0011] If the deviation difference is greater than a preset deviation threshold, the weld edge width is used as a constraint condition to plan a splicing trajectory, and the current welding trajectory of the welded object is corrected.

[0012] Optionally, the correction device further includes a plurality of motors, and the structural parameters include a module articulation distance, a screw articulation distance, and a bracket articulation distance; the method further includes:

[0013] When any of the capacitive sensors is not parallel to the weld bevel, calculating the required rotation angle corresponding to the capacitive sensor according to the plate spacing;

[0014] Determining the number of rotations of the motor based on the required rotation angle, the sensor tilt angle, and the structural parameters;

[0015] The motor is driven to rotate the lead screw according to the number of rotations until the capacitive sensor is parallel to the weld bevel.

[0016] Optionally, when any of the capacitive sensors is not parallel to the weld bevel, the step of calculating the required rotation angle corresponding to the capacitive sensor according to the plate spacing includes:

[0017] When any of the capacitive sensors is not parallel to the weld bevel, obtaining the distance between the upper sensing module and the lower sensing module in the capacitive sensor as the endpoint distance;

[0018] Calculating a board spacing difference between the board spacing of the upper sensing module and the board spacing of the lower sensing module;

[0019] The required rotation angle corresponding to the capacitive sensor is calculated according to the plate spacing difference and the endpoint distance.

[0020] Optionally, the step of determining the number of rotations corresponding to the motor based on the required rotation angle, the sensor tilt angle, and the structural parameters includes:

[0021] Calculating a target angle and a value between the required rotation angle and the sensor tilt angle;

[0022] Substituting the target angle and value, the module articulation distance, the screw articulation distance, and the bracket articulation distance into a preset cosine formula to determine the required height corresponding to the capacitive sensor;

[0023] The ratio between the required height and the unit adjustment height corresponding to the motor is calculated to obtain the number of rotations corresponding to the motor.

[0024] Optionally, the structural parameters further include charge, plate facing area, relative dielectric constant, and electrostatic force constant; and the step of determining the plate spacing between each capacitive sensor and the weld bevel, and the sensor tilt angle based on the structural parameters of each capacitive sensor at the current moment and the voltage information, comprises:

[0025] Substituting the charge amount, the plate facing area, the relative dielectric constant, the electrostatic force constant, and the voltage information into a preset plate spacing calculation formula to determine the plate spacing between each of the capacitive sensors and the weld bevel;

[0026] The module articulation distance, the screw rod articulation distance, and the bracket articulation distance are substituted into a preset angle calculation formula to determine the sensor tilt angle corresponding to each capacitive sensor.

[0027] Optionally, the correction device further includes a plurality of planar capacitive sensors, the planar capacitive sensors being connected to each group of the capacitive sensors and being placed horizontally, and the structural parameters further including a module array length; the step of determining the weld eccentricity and weld edge width of the welded object based on the plate spacing, the sensor inclination angle, and the structural parameters when all the capacitive sensors are parallel to the weld bevel, comprises:

[0028] When all the capacitance sensors are parallel to the weld bevel, respectively calculating the multiplication value of the distance between the plates and the sensor tilt angle using the capacitance sensor as a unit;

[0029] Calculating the difference between the multiplied values ​​of the distances to obtain the weld eccentricity of the welded object;

[0030] Obtaining a maximum vertical distance between the planar capacitive sensor and the welding object;

[0031] The distance between the plates, the tilt angle of the sensors, the module array length, the maximum vertical distance and the planar length of the planar capacitance sensor are substituted into a preset width calculation formula to determine the weld edge width of the welded object.

[0032] Optionally, the width calculation formula is:

[0033]

[0034] Wherein, w is the weld edge width, d1 is the module array length of the left capacitive sensor, d2 is the module array length of the right capacitive sensor, a1 is the maximum vertical distance of the left capacitive sensor, a2 is the maximum vertical distance of the right capacitive sensor, b1 is the plate spacing of the left capacitive sensor, b2 is the plate spacing of the right capacitive sensor, θ1 is the sensor tilt angle of the left capacitive sensor, θ2 is the sensor tilt angle of the right capacitive sensor, and m is the planar length of the planar capacitive sensor.

[0035] Optionally, the method further includes:

[0036] Calculating the voltage difference between any two sensing modules using the voltage information collected by the sensing modules in each of the capacitive sensors;

[0037] If the number of identical voltage differences exceeds a preset parallel threshold, it is determined that the capacitive sensor is parallel to the weld bevel;

[0038] If the number of identical voltage difference values ​​does not exceed a preset parallel threshold, it is determined that the capacitive sensors are not parallel to the weld bevel.

[0039] Optionally, the method further includes:

[0040] If the deviation difference is not greater than the preset deviation threshold, the process jumps to executing the step of acquiring in real time the voltage information generated between each of the capacitive sensors and the weld bevel of the welding object.

[0041] The present invention provides a welding track correction device, wherein a processor is communicatively connected with multiple groups of capacitive sensors, and the processor includes:

[0042] A voltage information acquisition module, configured to acquire in real time the voltage information generated between each of the capacitive sensors and the weld bevel of the weld object;

[0043] a sensing information calculation module, configured to determine the plate spacing between each of the capacitive sensors and the weld bevel, and the sensor tilt angle, based on the structural parameters of each of the capacitive sensors at a current moment and the voltage information;

[0044] a weld information calculation module, configured to determine the weld eccentricity and weld edge width of the welded object based on the plate spacing, the sensor inclination angle, and the structural parameters when all the capacitive sensors are parallel to the weld bevel;

[0045] a deviation difference calculation module, configured to calculate a deviation difference between a track center distance between the welding objects and an eccentricity of the weld;

[0046] The deviation correction module is used to plan the splicing trajectory using the weld edge width as a constraint condition if the deviation difference is greater than a preset deviation threshold, and to correct the current welding trajectory of the welded object.

[0047] It can be seen from the above technical solutions that the present invention has the following advantages:

[0048] The present invention obtains the voltage information generated between each capacitive sensor and the weld bevel of the welding object in real time. Based on the structural parameters and voltage information of each capacitive sensor at the current moment, the plate spacing between each capacitive sensor and the weld bevel and the sensor tilt angle are determined. When all capacitive sensors are parallel to the weld bevel, the weld eccentricity and weld edge width of the welding object are determined based on the plate spacing and sensor tilt angle. The deviation difference between the track center distance between the welding objects and the weld eccentricity is calculated. If the deviation difference is greater than a preset deviation threshold, the weld edge width is used as a constraint to plan the splicing trajectory, and the current welding trajectory of the welding object is corrected along the splicing trajectory. This reduces the amount of calculation of weld-related data without using visual sensors, effectively improving the accuracy of the welding trajectory correction of the welding robot. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0050] Figure 1 A flowchart of a welding trajectory correction method provided by an embodiment of the present invention;

[0051] Figure 2 A cross-sectional schematic diagram of a correction process between welding objects by a correction device provided by an embodiment of the present invention;

[0052] Figure 3 A schematic diagram of a welding trajectory correction process provided by an embodiment of the present invention;

[0053] Figure 4 A flowchart of a welding trajectory correction method provided by an embodiment of the present invention;

[0054] Figure 5 A detailed diagram of a partial structure of a correction device provided by an embodiment of the present invention;

[0055] Figure 6 A triangular relationship equivalent diagram of a partial structural refinement of a deviation correction device provided by an embodiment of the present invention;

[0056] Figure 7 A schematic diagram of the arrangement structure of a sensor module provided by an embodiment of the present invention;

[0057] Figure 8 A schematic diagram of a capacitive sensor adjustment process provided by an embodiment of the present invention;

[0058] Figure 9 A simplified three-dimensional diagram of the steel plate correction process of a correction device provided in an embodiment of the present invention;

[0059] Figure 10 This is a structural block diagram of a welding trajectory correction device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0060] An embodiment of the present invention provides a welding trajectory correction method and device, which is used to solve the technical problem that when the existing technology is applied in certain metal welding occasions, due to the high temperature and heat generated by the welding process, it is impossible to use infrared or laser ranging methods to maintain a constant distance between the welding head and the welded metal. At the same time, the use of visual sensors for welding object weld detection and welding trajectory correction has a large amount of calculation and poor real-time performance, which in turn leads to low correction accuracy.

[0061] In order to make the purpose, features, and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below 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 making creative work are within the scope of protection of the present invention.

[0062] See also Figure 1 , Figure 1 A flowchart of the steps of a welding trajectory correction method provided by an embodiment of the present invention.

[0063] The present invention provides a welding track correction method, which is applied to a processor in a correction device, wherein the processor is communicatively connected with multiple groups of capacitive sensors of the correction device, and the method includes:

[0064] Step 101, obtaining in real time the voltage information generated between each capacitive sensor and the weld bevel of the welding object;

[0065] The voltage information refers to the feedback voltage generated by the gap between the capacitive sensor as the positive electrode and the welding object as the negative electrode. It is used to represent the voltage difference between each sensing module in the capacitive sensor and the weld bevel of the welding object.

[0066] The welding object refers to an object with a weld bevel and for the correction device to perform welding operations, such as steel plates of different thicknesses.

[0067] In this embodiment of the present invention, a capacitive sensor is positioned opposite the weld bevel of the object being welded. With itself as the positive electrode and the object being welded as the negative electrode, a voltage differential is generated and transmitted to a processor within the correction device. The processor captures the voltage generated between each capacitive sensor and the object in real time, providing data for subsequent correction of the weld trajectory.

[0068] Step 102, determining the plate spacing between each capacitive sensor and the weld bevel, and the sensor tilt angle based on the structural parameters and voltage information of each capacitive sensor at the current moment;

[0069] The cross section of the correction process between the welding objects by the correction device is as follows Figure 2 As shown, it includes but is not limited to multiple sensor modules and motors. The motor controls the number of rotations of the screw rod by responding to control instructions and adjusts the sensor tilt angle of the sensor module so that most of the sensor modules are parallel to the weld bevel of the welding object.

[0070] After the processor obtains the voltage information uploaded by each capacitive sensor, the distance between each capacitive sensor and the weld bevel, as well as the current sensor tilt angle, can be calculated by combining the capacitive sensor's current structural parameters with the voltage information, since the structural parameters of each capacitive sensor may vary depending on the angle of the weld bevel.

[0071] Figure 2 It includes a capacitive sensor 2, a planar capacitive sensor 4, a planar capacitive sensor 12, a capacitive sensor 14, a planar capacitive sensor 16, a screw 6, a screw 10, a bracket 3, a bracket 13, a base 8, a servo motor 7, a servo motor 9, a nut 5, a nut 11, a steel plate 1, a steel plate 15 and a steel plate welding surface 17.

[0072] Step 103, when all capacitive sensors are parallel to the weld bevel, determine the weld eccentricity and weld edge width of the welded object based on the spacing between the plates, the inclination angle of each sensor, and the structural parameters;

[0073] In this embodiment, the parallelism of the capacitive sensor and the weld bevel can be judged according to the voltage information. When it is determined that the capacitive sensor and the weld bevel are parallel, a combined calculation can be performed according to the current plate spacing and the sensor inclination angle to determine the weld eccentricity and weld edge width of the welded object at the current moment.

[0074] It should be noted that the weld eccentricity refers to the distance between the actual welding trajectory generated by the welding robot after performing the welding operation and the central axis of the welding object. The weld edge width refers to the distance between the highest points of the weld bevel.

[0075] Step 104, calculating the deviation difference between the center distance of the track between the welding objects and the eccentricity of the weld;

[0076] The track center distance refers to the distance between the planned welding track and the center axis of the welding object.

[0077] In this embodiment, the welded objects are typically positioned symmetrically about their central axis before the welding operation. Thick steel plates are prone to uneven heating during welding, which can lead to weld cracks. After the welding robot completes the welding operation, the plate cools down, potentially causing delayed cracking. To ensure weld quality, the robot's tracking accuracy must be improved.

[0078] To this end, the deviation difference between the trajectory center distance between the welding objects and the weld eccentricity can be calculated and used as the data basis for judging whether the welding trajectory is deviated.

[0079] Step 105 : If the deviation difference is greater than a preset deviation threshold, the weld edge width is used as a constraint condition to plan the splicing trajectory, and the current welding trajectory of the welded object is corrected.

[0080] If the deviation difference is greater than the preset deviation threshold, it indicates that the current welding trajectory of the welded object deviates greatly from the planned trajectory. To avoid the position of the weld affecting other positions of the welded object, the weld edge width can be used as a constraint to plan the splicing trajectory, such as Figure 3 As shown in the figure, the actual running trajectory of the welding object is as shown before its detection point. After the weld eccentricity ΔzL is determined by detection, the deviation difference e is calculated:

[0081] e=dL1-△zL

[0082] Where dL1 is the distance between the planned trajectory and the central axis. If the deviation difference e is greater than the preset deviation threshold, the weld edge width is used as a constraint to plan a joint trajectory, which is the joint trajectory shown after the detection point. The current welding trajectory of the welded object is corrected along this joint trajectory.

[0083] Specifically, the trajectory planning algorithm can be called by using the weld edge width as a constraint condition to plan the splicing trajectory. The trajectory planning algorithm can be spline interpolation, dynamic programming algorithm or A algorithm, etc. The embodiment of the present invention does not limit the specific algorithm type.

[0084] After completing the planning of the splicing trajectory, the robotic arm of the welding robot and the execution angle of the welding operation are adjusted according to the splicing trajectory, and the current welding trajectory of the welding object is corrected along the splicing trajectory, thereby achieving high-precision trajectory correction of the welding object. At the same time, steps 101-105 are looped until the welding robot completes all welding operations on the welding object.

[0085] In an embodiment of the present invention, voltage information generated between each capacitive sensor and the weld bevel of the weld object is acquired in real time. Based on the structural parameters and voltage information of each capacitive sensor at the current moment, the plate spacing between each capacitive sensor and the weld bevel, as well as the sensor tilt angle, is determined. When all capacitive sensors are parallel to the weld bevel, the weld eccentricity and weld edge width of the weld object are determined based on the plate spacing and sensor tilt angles. The deviation difference between the trajectory center distance between the weld objects and the weld eccentricity is calculated. If the deviation difference is greater than a preset deviation threshold, the weld edge width is used as a constraint to plan the splicing trajectory, and the current welding trajectory of the weld object is corrected along the splicing trajectory. This reduces the computational complexity of weld-related data without using a visual sensor, effectively improving the accuracy of the welding robot's welding trajectory correction.

[0086] See also Figure 4 , Figure 4 A flowchart of the steps of a welding trajectory correction method provided by an embodiment of the present invention.

[0087] The present invention provides a welding trajectory correction method, which is applied to a processor in a correction device, wherein the processor is communicatively connected to multiple groups of capacitive sensors of the correction device. The correction device also includes multiple motors, and the structural parameters include module articulation distance, screw articulation distance, and bracket articulation distance. The method includes:

[0088] Step 201, obtaining in real time the voltage information generated between each capacitive sensor and the weld bevel of the welding object;

[0089] In the embodiment of the present invention, the specific implementation process of step 201 is similar to that of step 101 and will not be repeated here.

[0090] Step 202, determining the plate spacing between each capacitive sensor and the weld bevel, and the sensor tilt angle based on the structural parameters and voltage information of each capacitive sensor at the current moment;

[0091] Furthermore, the structural parameters also include charge, plate facing area, relative dielectric constant, and electrostatic force constant; step 202 may include the following sub-steps:

[0092] Substitute the charge, plate facing area, relative dielectric constant, electrostatic force constant, and voltage information into the preset plate spacing calculation formula to determine the plate spacing between each capacitive sensor and the weld bevel;

[0093] Substitute the module articulation distance, the screw articulation distance, and the bracket articulation distance into the preset angle calculation formula to determine the sensor tilt angle corresponding to each capacitive sensor.

[0094] In the embodiment of the present invention, Figure 5 The detailed diagram of the partial structure of the correction device in the figure is simplified into a triangle relationship equivalent diagram, such as Figure 2 and Figure 6 As shown, when the device structure is determined, capacitive sensors 2 and 14, screws 6 and 10, and brackets 3 and 13 are connected by hinges, allowing for rotational movement. These brackets form three hinge points: the linear distance between the hinge centers of capacitive sensor 2 and 14 is H2, the linear distance between the hinge centers of screw 6 and 10 is L2, and the linear distance between the hinge centers of bracket 3 and 13 is S2. The linear distance between the hinge centers of capacitive sensor 14 and 14 is H1, the linear distance between the hinge centers of screw 10 and 10 is L1, and the linear distance between the hinge centers of bracket 13 and 13 is S1. Servo motors 7 and 9 are controlled to rotate screws 6 and 10, and nuts 5 and 11 move up and down with the rotation of screws 6 and 10, meaning L1 and L2 change. When the corrective device structure is determined, H1, S1, H2, and S2 are also fixed values. At this point, the plate spacing and angle calculation formulas can be used to calculate the plate spacing and sensor tilt angle corresponding to each group of capacitive sensors, by substituting the corresponding parameters.

[0095] It should be noted that the calculation formula for the plate spacing is:

[0096]

[0097] Among them, b x is the plate distance between the xth group of capacitance sensors and the weld bevel, ε is the relative dielectric constant, S is the area of ​​the plates facing each other, k is the electrostatic force constant, Q is the charge, and U is the ... x is the voltage information of the x-th group of capacitance sensors, and π is the pi;

[0098] The angle calculation formula is:

[0099]

[0100] Among them, θ x is the sensor tilt angle of the x-th group of capacitive sensors, L x S is the screw articulation distance of the xth group of capacitance sensors, x H is the hinge distance of the bracket of the x-th group of capacitance sensors. x is the module articulation distance of the xth group of capacitive sensors.

[0101] Optionally, the method further comprises the following steps S11-S13:

[0102] S11, using the voltage information collected by the sensing modules in each capacitive sensor, respectively, to calculate the voltage difference between any two sensing modules;

[0103] See also Figure 7 , Figure 7 FIG. 1 is a schematic diagram showing the arrangement structure of multiple sensing modules in a single group of capacitive sensors in an embodiment of the present invention.

[0104] In the embodiment of the present invention, each sensor module feeds back the voltage information of its corresponding area, namely U1, U2, U3, U4...U i+1 、U i+2 、U i+3 、U i+4 The voltage difference ΔU(i,j) between any two sensor modules is calculated using the voltage information collected by each sensor module:

[0105] ΔU(i,j)=U i -U j , i≠j

[0106] Since the voltage information detected by different sensor modules will show different values ​​when they are not parallel, the number of identical voltage differences can be further counted, and the comparison result between this and the preset parallel threshold can be used to determine whether the capacitive sensor and the weld bevel are parallel.

[0107] S12. If the number of identical voltage differences exceeds a preset parallel threshold, it is determined that the capacitive sensor is parallel to the weld bevel.

[0108] S13. If the number of identical voltage differences does not exceed the preset parallel threshold, it is determined that the capacitive sensors are not parallel to the weld bevel.

[0109] In this embodiment of the present invention, if identical voltage differences exist and their number exceeds a preset parallel threshold, it indicates that most sensor modules are parallel to the weld bevel, and the capacitive sensor can be determined to be parallel to the weld bevel. If identical voltage differences do not exist, or if the number of identical voltage differences does not exceed the preset parallel threshold, the capacitive sensor can be determined to be non-parallel to the weld bevel. By analyzing the changes in voltage information and the number of such differences, it is possible to prevent visual sensor failure or image data distortion caused by high welding temperatures and accurately determine the relative parallelism between the capacitive sensor and the weld bevel.

[0110] Step 203 , when any capacitive sensor is not parallel to the weld bevel, calculating the required rotation angle corresponding to the capacitive sensor according to the plate spacing;

[0111] Optionally, step 203 may include the following sub-steps:

[0112] When any capacitive sensor is not parallel to the weld bevel, the distance between the upper sensing module and the lower sensing module in the capacitive sensor is obtained as the endpoint distance;

[0113] Calculating a board spacing difference between the board spacing of the upper sensing module and the board spacing of the lower sensing module;

[0114] Calculate the required rotation angle corresponding to the capacitive sensor based on the board spacing difference and endpoint distance.

[0115] The upper sensing module refers to any sensing module located in the upper half of the capacitive sensor above the midline, and the lower sensing module refers to any sensing module located in the lower half of the capacitive sensor below the midline.

[0116] like Figure 8 As shown, when any capacitive sensor is not parallel to the weld bevel, for this capacitive sensor, the plate spacing difference can be obtained by obtaining the plate spacing of the upper sensor module and the plate spacing of the lower sensor module, and calculating the difference between the two. The required rotation angle Δθ corresponding to the capacitive sensor can then be calculated based on the endpoint distance. x :

[0117]

[0118] Among them, b up is the board spacing of the upper sensor module, b down is the board spacing of the lower end sensor module, h is the end point distance, b up and b down It can be calculated by referring to the plate spacing calculation formula.

[0119] Step 204, determining the corresponding number of rotations of the motor based on the required rotation angle, the sensor tilt angle and the structural parameters;

[0120] Optionally, step 204 may include the following sub-steps:

[0121] Calculate the target angle and value between the rotation requirement angle and the sensor tilt angle;

[0122] Substitute the target angle and value, module articulation distance, screw articulation distance, and bracket articulation distance into the preset cosine formula to determine the required height corresponding to the capacitive sensor;

[0123] Calculate the ratio between the required height and the unit adjustment height of the motor to get the corresponding number of rotations of the motor;

[0124] The default cosine formula is:

[0125] H x 2 +(L x +ΔL x ) 2 -S x 2 =2cos(θ x +Δθ x )(L x +ΔL x )H x

[0126] Among them, H x L is the module articulation distance of the xth group of capacitive sensors. x is the screw articulation distance of the xth group of capacitance sensors, ΔL x is the required height of the xth group of capacitance sensors, S x is the hinge distance of the bracket of the x-th group of capacitive sensors, Δθ x is the required rotation angle of the xth group of capacitance sensors, θ x is the sensor tilt angle of the x-th group of capacitive sensors.

[0127] It should be noted that the unit height adjustment refers to the height adjusted by the motor driving the screw rod for one rotation. The required height can be positive or negative, with a positive value indicating upward rotation and a negative value indicating downward rotation.

[0128] Step 205 , driving the motor to rotate the lead screw according to the number of revolutions until the capacitive sensor is parallel to the weld bevel;

[0129] In an embodiment of the present invention, the motor is driven to drive the screw to rotate upward or downward according to the number of rotations. At the same time, in order to timely judge its parallel state, the process can jump to step 201, obtain its voltage information in real time, and perform parallel judgment according to the process of steps S11-S13 until it is determined that the capacitive sensor is parallel to the weld bevel.

[0130] Step 206 , when all capacitive sensors are parallel to the weld bevel, determine the weld eccentricity and weld edge width of the welded object based on the spacing between the plates and the inclination angle of each sensor;

[0131] Optionally, the correction device further includes a plurality of planar capacitive sensors, which are connected to each group of capacitive sensors and placed horizontally. The structural parameters also include module array length. Step 206 may include the following sub-steps:

[0132] When all capacitance sensors are parallel to the weld bevel, the multiplication of the distance between the plates and the sensor tilt angle is calculated using capacitance sensors as units;

[0133] Calculate the difference between the multiplied values ​​of each distance to obtain the weld eccentricity of the welded object;

[0134] Get the maximum vertical distance between the planar capacitive sensor and the welding object;

[0135] The distance between the plates, the tilt angle of each sensor, the module array length, the maximum vertical distance, and the planar length of the planar capacitance sensor are substituted into a preset width calculation formula to determine the weld edge width of the welded object.

[0136] In one example of the present invention, the width calculation formula is:

[0137]

[0138] Wherein, w is the weld edge width, d1 is the module array length of the left capacitive sensor, d2 is the module array length of the right capacitive sensor, a1 is the maximum vertical distance of the left capacitive sensor, a2 is the maximum vertical distance of the right capacitive sensor, b1 is the plate spacing of the left capacitive sensor, b2 is the plate spacing of the right capacitive sensor, θ1 is the sensor tilt angle of the left capacitive sensor, θ2 is the sensor tilt angle of the right capacitive sensor, and m is the planar length of the planar capacitive sensor.

[0139] See also Figure 2 and Figure 9 , Figure 9 This is a simplified three-dimensional diagram of the steel plate correction process of a correction device according to an embodiment of the present invention.

[0140] In this embodiment, after determining the parallelism between each capacitive sensor and the weld bevel one by one, if it is determined that all capacitive sensors and the weld bevel are parallel, and the plate spacing between each capacitive sensor and the weld bevel is the same, and the sensor inclination angle is equal to the inclination angle of the weld bevel, the distance multiplied between the two can be calculated based on the plate spacing and sensor inclination angle of each capacitive sensor. The difference between the distance multiplied values ​​is then calculated to obtain the weld eccentricity of the weld object. Taking two groups of capacitive sensors on the left and right sides, and the weld object is a steel plate as an example, when the steel plate is thick, it is prone to uneven heating during the welding process, and therefore weld cracks are likely to occur during the welding process. After welding, the temperature of the steel plate cools down, and there is a probability of delayed cracking. To ensure welding quality, it is necessary to improve the accuracy of the robot tracking the welding trajectory. The robot is moving in a complex space during the steel plate welding process, and errors will inevitably occur between the actual trajectory and the planned trajectory of the robot during the movement. The distance between the capacitive sensor 14 and the inclined surface of the steel plate 15 is b1, the distance between the capacitive sensor 2 and the inclined surface of the steel plate 1 is b2, the inclined angle of the steel plate 15 is θ1, and the inclined angle of the steel plate [1] is θ2. Through the geometric relationship, it can be known that the weld eccentricity (ΔzL) can be calculated:

[0141] ΔzL=b1cosθ1-b2cosθ2

[0142] The weld eccentricity calculated using the above formula is used to promptly correct the welding trajectory of the robot's end-of-line device. The correction device provides real-time information on the angle between the steel plate's slope and the horizontal plane, as well as the weld width. This information assists the robot in correcting the planned welding trajectory. The accuracy of the robot's planned welding trajectory ensures welding quality.

[0143] In a specific implementation, the module array length of the capacitive sensor 2 is d2, the planar length of the planar capacitive sensor 16 is m, the distance between the capacitive sensor 14 and the oblique surface of the steel plate 15 when they are parallel is b1, the distance between the capacitive sensor 2 and the oblique surface of the steel plate 1 when they are parallel is b2, the module array length of the capacitive sensor 14 is d1, when the planar capacitive sensor 12 and the horizontal plane of the steel plate 15 are parallel, the distance a1 can be measured, when the planar capacitive sensor 4 and the horizontal plane of the steel plate 1 are parallel, the distance a2 can be measured, the oblique angle of the steel plate 15 is θ1, and the oblique angle of the steel plate 1 is θ2, then the weld edge width w can be obtained by b1, b2, θ1, θ2, a1, a2, d1, d2, m.

[0144] Step 207, calculating the deviation difference between the center distance of the track between the welding objects and the eccentricity of the weld;

[0145] Step 208 : If the deviation difference is greater than a preset deviation threshold, the weld edge width is used as a constraint condition to plan the splicing trajectory, and the current welding trajectory of the welded object is corrected.

[0146] In the embodiment of the present invention, the specific implementation process of steps 207-208 is similar to that of steps 104-105 and will not be repeated here.

[0147] Furthermore, the method further comprises:

[0148] If the deviation difference is not greater than the preset deviation threshold, the process jumps to executing a step of acquiring voltage information generated between each capacitance sensor and the weld bevel of the welding object in real time.

[0149] In an example of the present invention, if the deviation difference is not greater than the preset deviation threshold, it indicates that the current welding trajectory is still in a normal state. At this time, the process can jump to step 201 to monitor the weld condition of the welded object in real time.

[0150] In an embodiment of the present invention, voltage information generated between each capacitive sensor and the weld bevel of the welded object is acquired in real time. Based on the structural parameters and voltage information of each capacitive sensor at the current moment, the plate spacing between each capacitive sensor and the weld bevel, as well as the sensor tilt angle, is determined. When all capacitive sensors are parallel to the weld bevel, the weld eccentricity and weld edge width of the welded object are determined based on the plate spacing and sensor tilt angles. The deviation difference between the track center distance between the welded objects and the weld eccentricity is calculated. If the deviation difference is greater than a preset deviation threshold, the weld edge width is used as a constraint to plan the splicing trajectory, and the current welding trajectory of the welded objects is corrected along the splicing trajectory. This reduces the computational effort required for weld-related data without the use of visual sensors, effectively improving the accuracy of the correction device's weld trajectory correction.

[0151] See also Figure 10 , Figure 10 A structural block diagram of a welding trajectory correction device in an embodiment of the present invention is shown.

[0152] An embodiment of the present invention provides a welding trajectory correction device, wherein a processor is communicatively connected to multiple groups of capacitive sensors, and the processor includes:

[0153] The voltage information acquisition module 301 is used to obtain the voltage information generated between each capacitance sensor and the weld bevel of the welding object in real time;

[0154] The sensor information calculation module 302 is used to determine the plate spacing between each capacitive sensor and the weld bevel, as well as the sensor tilt angle based on the structural parameters and voltage information of each capacitive sensor at the current moment;

[0155] The weld information calculation module 303 is used to determine the weld eccentricity and weld edge width of the welded object based on the spacing between the plates, the inclination angle of each sensor, and the structural parameters when all the capacitive sensors are parallel to the weld bevel;

[0156] The deviation difference calculation module 304 is used to calculate the deviation difference between the center distance of the track between the welding objects and the eccentricity of the weld;

[0157] The deviation correction module 305 is used to plan the splicing trajectory using the weld edge width as a constraint condition if the deviation difference is greater than a preset deviation threshold, and to correct the current welding trajectory of the welded object.

[0158] Optionally, the correction device further includes a plurality of motors, and the structural parameters include a module articulation distance, a screw articulation distance, and a bracket articulation distance; the device further includes:

[0159] A rotational required angle calculation module is used to calculate the corresponding rotational required angle of the capacitance sensor according to the plate spacing when any capacitance sensor is not parallel to the weld bevel;

[0160] A rotation number determination module is used to determine the corresponding number of rotations of the motor based on the required rotation angle, the sensor tilt angle and the structural parameters;

[0161] The motor drive module is used to drive the motor to rotate the screw according to the number of rotations until the capacitive sensor is parallel to the weld bevel.

[0162] Optionally, the rotation requirement angle calculation module is specifically used to:

[0163] When any capacitive sensor is not parallel to the weld bevel, the distance between the upper sensing module and the lower sensing module in the capacitive sensor is obtained as the endpoint distance;

[0164] Calculating a board spacing difference between the board spacing of the upper sensing module and the board spacing of the lower sensing module;

[0165] Calculate the required rotation angle corresponding to the capacitive sensor based on the board spacing difference and endpoint distance.

[0166] Optionally, the rotation number determination module is specifically configured to:

[0167] Calculate the target angle and value between the rotation requirement angle and the sensor tilt angle;

[0168] Substitute the target angle and value, module articulation distance, screw articulation distance, and bracket articulation distance into the preset cosine formula to determine the required height corresponding to the capacitive sensor;

[0169] Calculate the ratio between the required height and the unit adjustment height corresponding to the motor to obtain the corresponding number of rotations of the motor.

[0170] Optionally, the structural parameters also include charge, plate facing area, relative dielectric constant, and electrostatic force constant; the sensing information calculation module 302 is specifically used to:

[0171] Substitute the charge, plate facing area, relative dielectric constant, electrostatic force constant, and voltage information into the preset plate spacing calculation formula to determine the plate spacing between each capacitive sensor and the weld bevel;

[0172] Substitute the module articulation distance, the screw articulation distance, and the bracket articulation distance into the preset angle calculation formula to determine the sensor tilt angle corresponding to each capacitive sensor.

[0173] Optionally, the correction device further includes a plurality of planar capacitive sensors, which are connected to each group of capacitive sensors and placed horizontally, and the structural parameters also include the module array length; the weld information calculation module 303 is specifically used to:

[0174] When all capacitance sensors are parallel to the weld bevel, the multiplication of the distance between the plates and the sensor tilt angle is calculated using capacitance sensors as units;

[0175] Calculate the difference between the multiplied values ​​of each distance to obtain the weld eccentricity of the welded object;

[0176] Get the maximum vertical distance between the planar capacitive sensor and the welding object;

[0177] The distance between the plates, the tilt angle of each sensor, the module array length, the maximum vertical distance, and the planar length of the planar capacitance sensor are substituted into a preset width calculation formula to determine the weld edge width of the welded object.

[0178] Optionally, the width is calculated as:

[0179]

[0180] Wherein, w is the weld edge width, d1 is the module array length of the left capacitive sensor, d2 is the module array length of the right capacitive sensor, a1 is the maximum vertical distance of the left capacitive sensor, a2 is the maximum vertical distance of the right capacitive sensor, b1 is the plate spacing of the left capacitive sensor, b2 is the plate spacing of the right capacitive sensor, θ1 is the sensor tilt angle of the left capacitive sensor, θ2 is the sensor tilt angle of the right capacitive sensor, and m is the planar length of the planar capacitive sensor.

[0181] Optionally, the device further comprises:

[0182] A voltage difference calculation module is used to calculate the voltage difference between any two sensing modules using the voltage information collected by the sensing modules in each capacitive sensor;

[0183] a parallel determination module, configured to determine that the capacitive sensor is parallel to the weld bevel if the number of identical voltage differences exceeds a preset parallel threshold;

[0184] The parallel denial module is used to determine that the capacitive sensors are not parallel to the weld bevel if the number of identical voltage differences does not exceed a preset parallel threshold.

[0185] Optionally, the device further comprises:

[0186] The jump loop module is used to jump to the step of obtaining the voltage information generated between each capacitance sensor and the weld bevel of the welding object in real time if the deviation difference is not greater than the preset deviation threshold.

[0187] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described devices and modules can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0188] In the several embodiments provided by the present invention, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the modules is merely a logical function division. In actual implementation, there may be other division methods, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be through some interface, indirect coupling or communication connection of devices or modules, which can be electrical, mechanical or other forms.

[0189] The modules described as separate components may or may not be physically separate, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed across multiple network modules. Some or all of the modules may be selected to achieve the purpose of the present embodiment according to actual needs.

[0190] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features thereof can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A welding trajectory correction method, characterized in that: A processor is applied to a correction device, the processor being communicatively connected to multiple groups of capacitive sensors of the correction device, and the method includes: Real-time acquisition of voltage information generated between each of the capacitive sensors and the weld bevel of the weld object; Determining the plate spacing between each capacitive sensor and the weld bevel, and the sensor tilt angle, based on the structural parameters of each capacitive sensor at a current moment and the voltage information; the structural parameters include a module hinge distance, a screw hinge distance, a bracket hinge distance, a charge, a plate facing area, a relative dielectric constant, and an electrostatic force constant; When all the capacitive sensors are parallel to the weld bevel, determining the weld eccentricity and weld edge width of the welded object according to the plate spacing, the sensor inclination angle and the structural parameters; Calculating the deviation difference between the center distance of the track between the welding objects and the eccentricity of the weld; If the deviation difference is greater than a preset deviation threshold, the weld edge width is used as a constraint condition to plan a splicing trajectory, and the current welding trajectory of the welded object is corrected; The step of determining the plate spacing between each capacitive sensor and the weld bevel, and the sensor tilt angle based on the structural parameters of each capacitive sensor at the current moment and the voltage information, comprises: Substituting the charge amount, the plate facing area, the relative dielectric constant, the electrostatic force constant, and the voltage information into a preset plate spacing calculation formula to determine the plate spacing between each of the capacitive sensors and the weld bevel; The module articulation distance, the screw rod articulation distance, and the bracket articulation distance are substituted into a preset angle calculation formula to determine the sensor tilt angle corresponding to each capacitive sensor.

2. The method according to claim 1, characterized in that The correction device further includes a plurality of motors; and the method further includes: When any of the capacitive sensors is not parallel to the weld bevel, calculating the required rotation angle corresponding to the capacitive sensor according to the plate spacing; Determining the number of rotations of the motor based on the required rotation angle, the sensor tilt angle, and the structural parameters; The motor is driven to rotate the lead screw according to the number of rotations until the capacitive sensor is parallel to the weld bevel.

3. The method according to claim 2, characterized in that The step of calculating the required rotation angle corresponding to the capacitive sensor according to the plate spacing when any of the capacitive sensors is not parallel to the weld bevel includes: When any of the capacitive sensors is not parallel to the weld bevel, obtaining the distance between the upper sensing module and the lower sensing module in the capacitive sensor as the endpoint distance; Calculating a board spacing difference between the board spacing of the upper sensing module and the board spacing of the lower sensing module; The required rotation angle corresponding to the capacitive sensor is calculated according to the plate spacing difference and the endpoint distance.

4. The method according to claim 2, characterized in that The step of determining the number of rotations corresponding to the motor based on the required rotation angle, the sensor tilt angle, and the structural parameters includes: Calculating a target angle and a value between the required rotation angle and the sensor tilt angle; Substituting the target angle and value, the module articulation distance, the screw articulation distance, and the bracket articulation distance into a preset cosine formula to determine the required height corresponding to the capacitive sensor; The ratio between the required height and the unit adjustment height corresponding to the motor is calculated to obtain the number of rotations corresponding to the motor.

5. The method according to claim 1, characterized in that The correction device further includes a plurality of planar capacitive sensors connected to each group of the capacitive sensors and arranged horizontally, and the structural parameters further include a module array length; the step of determining the weld eccentricity and weld edge width of the welded object based on the spacing between the plates, the inclination angle of each sensor, and the structural parameters when all the capacitive sensors are parallel to the weld bevel comprises: When all the capacitance sensors are parallel to the weld bevel, respectively calculating the multiplication value of the distance between the plates and the sensor tilt angle using the capacitance sensor as a unit; Calculating the difference between the multiplied values ​​of the distances to obtain the weld eccentricity of the welded object; Obtaining a maximum vertical distance between the planar capacitive sensor and the welding object; The distance between the plates, the tilt angle of the sensors, the module array length, the maximum vertical distance and the planar length of the planar capacitance sensor are substituted into a preset width calculation formula to determine the weld edge width of the welded object.

6. The method according to claim 5, characterized in that The width calculation formula is: ； in, is the weld edge width, is the module array length of the left capacitive sensor, is the module array length of the right capacitive sensor, is the maximum vertical distance of the left capacitive sensor, is the maximum vertical distance of the right capacitive sensor, is the plate spacing of the left capacitive sensor, is the plate spacing of the right capacitive sensor, is the sensor tilt angle of the left capacitive sensor, is the sensor tilt angle of the right capacitive sensor, is the planar length of the planar capacitive sensor.

7. The method according to claim 1, characterized in that The method further comprises: Calculating the voltage difference between any two sensing modules using the voltage information collected by the sensing modules in each of the capacitive sensors; If the number of identical voltage differences exceeds a preset parallel threshold, it is determined that the capacitive sensor is parallel to the weld bevel; If the number of identical voltage difference values ​​does not exceed a preset parallel threshold, it is determined that the capacitive sensors are not parallel to the weld bevel.

8. The method according to claim 1, characterized in that The method further comprises: If the deviation difference is not greater than the preset deviation threshold, the process jumps to executing the step of acquiring in real time the voltage information generated between each of the capacitive sensors and the weld bevel of the welding object.

9. A welding track correction device, characterized in that: A processor is communicatively connected to the plurality of capacitive sensors, the processor comprising: A voltage information acquisition module, configured to acquire in real time the voltage information generated between each of the capacitive sensors and the weld bevel of the weld object; a sensing information calculation module, configured to determine the plate spacing between each capacitive sensor and the weld bevel, and the sensor tilt angle based on the structural parameters of each capacitive sensor at a current moment and the voltage information; the structural parameters including the module hinge distance, the screw hinge distance, the bracket hinge distance, the charge, the plate facing area, the relative dielectric constant, and the electrostatic force constant; a weld information calculation module, configured to determine the weld eccentricity and weld edge width of the welded object based on the plate spacing, the sensor inclination angle, and the structural parameters when all the capacitive sensors are parallel to the weld bevel; a deviation difference calculation module, configured to calculate a deviation difference between a track center distance between the welding objects and an eccentricity of the weld; a deviation correction module, configured to plan a splicing trajectory using the weld edge width as a constraint condition and correct the current welding trajectory of the welded object if the deviation difference is greater than a preset deviation threshold; The sensor information calculation module is specifically used to: Substituting the charge amount, the plate facing area, the relative dielectric constant, the electrostatic force constant, and the voltage information into a preset plate spacing calculation formula to determine the plate spacing between each of the capacitive sensors and the weld bevel; The module articulation distance, the screw rod articulation distance, and the bracket articulation distance are substituted into a preset angle calculation formula to determine the sensor tilt angle corresponding to each capacitive sensor.

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