CN113146026B - Self-adaptive welding seam tracking method - Google Patents
Self-adaptive welding seam tracking method Download PDFInfo
- Publication number
- CN113146026B CN113146026B CN202110460921.6A CN202110460921A CN113146026B CN 113146026 B CN113146026 B CN 113146026B CN 202110460921 A CN202110460921 A CN 202110460921A CN 113146026 B CN113146026 B CN 113146026B
- Authority
- CN
- China
- Prior art keywords
- laser
- welding seam
- lens group
- welding
- tracking method
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/02—Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
- B23K26/04—Automatically aligning, aiming or focusing the laser beam, e.g. using the back-scattered light
- B23K26/044—Seam tracking
Abstract
The invention discloses a self-adaptive welding seam tracking method, wherein a diode laser generator obliquely emits a laser beam, the laser beam falls on a workpiece and is split in the X direction of a working plane, an imaging system receives a real-time image sequence and simultaneously measures the image to obtain the current welding seam position, the deviation value of the current laser spot position and the current welding seam position is calculated, the deviation value is converted into an analog quantity and is transmitted to a laser lens group angle adjusting mechanism, and the laser lens group angle adjusting mechanism controls a welding optical system according to an angle numerical value. The invention obtains the current welding seam position in real time through an image processing technology, feeds the position back to the control unit, further controls the motor and the transmission mechanism to act to adjust the angle of the laser mirror group, realizes the real-time measurement and correction of the laser facula at the position to be welded, has the advantages of high welding seam tracking precision and quick response, and can obviously improve the efficiency and the quality of laser fusion welding.
Description
Technical Field
The invention relates to an automatic laser welding technology, in particular to a self-adaptive welding seam tracking method.
Background
Laser welding is used as an efficient and precise welding mode, compared with the traditional welding process, the laser welding method has the advantages of small heat input quantity, small thermal deformation, large depth-to-width ratio of a welding line, high welding speed and the like, and is widely applied to the industrial fields of spaceflight, automobiles and the like. The precise processing mode of the welding machine has higher challenge on the assembly precision of workpieces to be welded.
In the laser fusion welding process, whether the laser spots emitted by the laser mirror group can perform self-adaptive tracking on the welding seam position in real time and accurately is significant for the laser fusion welding process.
Disclosure of Invention
The purpose of the invention is as follows: aiming at the problems in the prior art, the invention provides a real-time and accurate self-adaptive welding seam tracking method.
The technical scheme is as follows: the invention relates to a self-adaptive weld tracking method.A adopted weld tracking device comprises a laser lens group, a laser lens group angle adjusting mechanism and a diode laser generator, wherein the top of the laser lens group is provided with a camera, and the diode laser generator is obliquely fixed at the front end of the laser lens group through a connecting bracket;
the welding joint aimed by the self-adaptive weld joint tracking is in angle joint or lap joint, and the corresponding workpiece comprises an upper plate and a lower plate;
the specific steps of the weld joint tracking are as follows:
(1) the diode laser generator obliquely emits laser beams, the laser beams fall on a workpiece and split in the X direction of a working plane, and the X direction is the tangential direction of a welding seam;
(2) the camera collects split images of the laser beams in real time and sends the images to the computer; each image comprises a split laser beam and a laser spot, the position of a welding seam is determined through the split position of the laser beam, and PV is defined as the coordinate value of the welding seam position of the previous image in the Y direction, namely the coordinate value of the current laser spot in the Y direction, by taking the edge of the upper laminate as a reference; defining SP as a coordinate value of the welding seam position of the current image in the Y direction; the Y direction is a direction perpendicular to a tangent of the welding seam on the working plane;
(3) defining a deviation value of the current laser spot and the target welding seam position in the Y direction as E, wherein E is SP-PV;
(4) converting the deviation into analog quantity, and transmitting the analog quantity to a laser mirror group angle adjusting mechanism;
(5) the laser mirror group angle adjusting mechanism controls the laser mirror group to change the angle in the Y direction, so that the laser spot is adjusted to be at the correct welding position.
Further, a camera is arranged to acquire images at the frequency of i frames per second, i deviation values in each second are summed, and the sum is multiplied by a controlled position proportionality coefficient K to obtain a voltage control signal
Wherein E isjThe error distance between the laser spot and the target weld position in the jth frame image in the Y direction is j more than or equal to 0 and less than or equal to i-1, k is a controlled position proportion coefficient determined during system calibration and is related to the parameters of the laser mirror group angle adjusting mechanism; the controlled position scaling factor K is preferably determined by regression analysis of the measurement data.
Furthermore, the diode laser generator is fixed at the front end of the laser mirror group by inclining 45 degrees through the connecting bracket.
Furthermore, the number of the diode laser generators is 2, and the diode laser generators are respectively arranged on two sides of the front end of the laser mirror group and used for tracking welding seams in different welding directions.
Furthermore, the laser mirror group angle adjusting mechanism comprises a servo motor, a screw rod transmission structure and a pair of hinged mounting plates; the laser lens group is arranged on one side of the mounting plate, and the servo motor and the screw rod transmission structure are arranged on the other side of the mounting plate; computer obtains control signal UiAfter that, the air conditioner is started to work,the servo motor is controlled to rotate, the screw rod transmission structure converts the rotary motion of the screw rod into linear motion to be output, the hinge angle of the pair of mounting plates is controlled to change, and then the angle of the laser lens group is adjusted.
Furthermore, two ends of the screw rod transmission structure are provided with limit sensors for limiting the swing amplitude of the light spot position of the laser mirror group in the Y-axis direction.
Furthermore, the welding seam tracking device comprises an ST control box, after the computer converts the deviation between the processed current laser spot position and the calibrated welding seam position into an analog quantity, the analog quantity is output to the ST control box through a field bus EtherCAT protocol, then the ST control box transmits the analog quantity to a servo motor of the laser mirror group angle adjusting mechanism through the same field bus EtherCAT, and the angle of the laser mirror group is controlled through a screw rod transmission structure and a mounting plate.
Furthermore, a power supply circuit of the diode laser generator is arranged in the ST control box.
Furthermore, a safety loop is arranged in the ST control box and used for controlling the debugging/working state of the diode laser generator.
Compared with the prior art, the invention has the following beneficial effects: the current welding seam position is obtained in real time through an image processing technology, the position is fed back to the control unit, the motor and the transmission mechanism are further controlled to act to adjust the angle of the laser mirror group, real-time measurement and correction of laser spots at the position to be welded are achieved, the laser fusion welding method has the advantages of being high in welding seam tracking accuracy and fast in response, and laser fusion welding efficiency and quality can be remarkably improved.
Drawings
FIG. 1 is a front view of a weld tracking apparatus;
FIG. 2 is a basic building block within the weld tracking apparatus;
FIG. 3 is a weld tracking control and feedback system;
FIG. 4 is a laser beam splitting diagram of a diode laser generator;
fig. 5 is a laser beam split view taken at a camera angle.
Detailed Description
The technical solution of the present invention is further described in detail below with reference to the accompanying drawings.
The invention discloses a self-adaptive weld joint tracking method, which adopts a structure of a weld joint tracking device as shown in figure 1, and comprises a laser lens group 1, a laser lens group angle adjusting mechanism 2 and a diode laser generator 3, wherein a camera 4 is arranged at the top of the laser lens group, the diode laser generator 2 is obliquely fixed on a connecting plate 6 at the front end of the laser lens group 1 through a connecting bracket 5, and the left side and the right side of the connecting plate 6 in figure 1 are respectively provided with one diode laser generator 3 for welding in different directions.
Fig. 2 shows the modules inside the device and the connection communication method, wherein the laser processing tool includes a laser lens set, a camera, a limit sensor, a servo module (motor and transmission mechanism), and the like. The camera, the weld joint tracking control computer and the ST control cabinet are controlled through mutual communication of EtherCAT, the weld joint tracking control computer is provided with an imaging system, and a robot carrying a laser processing tool is connected with the control weld joint tracking control computer through an industrial field bus. And a camera integrated on the laser welding tool shoots the current welding seam position, the information of the shooting is transmitted to a welding seam tracking control computer, and an imaging system in the welding seam tracking control computer processes and analyzes the image to obtain the current laser spot and the error of the target welding seam. And the weld tracking control computer transmits the control instruction to the ST control cabinet, and the ST control cabinet controls the servo module to act so as to control the angle of the laser lens group, namely, the working position of the light spot is adjusted, thereby realizing the weld tracking function.
With reference to fig. 3-5, the specific process of the adaptive seam tracking method is elaborated in detail by taking fillet welding as an example:
in the coordinate system of this embodiment, the X direction is defined as the tangential direction of the weld on the working plane, and the Y direction is defined as the direction perpendicular to the tangential direction of the weld on the working plane.
And 3, defining the error distance between the current laser spot and the target weld joint position in the Y direction as E, wherein E is SP-PV.
Step 4, as the camera and the laser lens group follow up coaxially, when the camera acquires pictures at a specific frequency, the reference standard changes every time; therefore, the deviation values of i times per second are summed and multiplied by the controlled position scaling factor K to obtain the voltage control signal
Wherein E isjK is the error distance of the laser spot and the target weld position in the jth image in the Y direction, is obtained by performing quantitative statistical regression analysis on a large amount of measurement data during system calibration, and is related to the parameters of the laser mirror group angle adjusting mechanism. The error of each frame in one second is accumulated, so that the welding seam tracking is more real-time, and the result is more accurate.
And 5, converting the processed deviation between the current position and the calibrated position into an analog quantity (voltage) by the computer, outputting the analog quantity (voltage) to a control board card in the ST control box through a field bus EtherCAT protocol, and transmitting the analog quantity to the laser mirror group angle adjusting mechanism through the same communication protocol field bus EtherCAT, wherein the laser mirror group angle adjusting mechanism controls the laser mirror group to generate angle change in the Y direction, so that the laser spot is adjusted at the correct welding position. Specifically, a motor control board card is arranged in the ST control box and used for controlling the number of rotating circles of the servo motor and positive and negative rotation, the laser lens group is adjusted in the positive Y direction in positive rotation, and the laser lens group is adjusted in the negative Y direction in negative rotation.
In addition, the ST control box is internally provided with a power supply and safety loop of the diode laser generator. At first, the light emitting of the diode laser generator needs to provide power, but the light emitted by the diode can be harmful to the human body, so when a power supply loop is arranged in the ST control box, a safety loop is also arranged, when the ST control box normally works, the door of a laser room is closed, the diode laser generator is controlled to be in a working state, when the ST control box is in a debugging state, the laser room door is opened, the loop in the ST control box can be in a short circuit state through an on-off key or a key, and the diode can only emit light through manual debugging.
The angle adjustment of the laser mirror group is realized in various ways, the transmission structure can adopt a screw rod and a nut (or a sliding block), the nut (or the sliding block) is installed on the screw rod, the screw rod is connected with the output shaft of a motor and rotates along with the rotation of the motor, the rotation motion of the screw rod is converted into the linear motion of the nut (or the sliding block) in the Y direction, namely, the output of the linear motion is realized, a projection structure is further assisted on the nut (or the sliding block) and is used as the acting force output end of the linear motion, the acting force of the projection structure is in the Y direction, and the projection structure directly or indirectly acts on the laser mirror group. In order to realize the angle adjustment of the laser lens group, a pair of mounting plates with hinged tail ends can be arranged, wherein one mounting plate is a fixed plate, the other mounting plate is a movable plate, the included angle is 0 when the two mounting plates are folded, and when the movable plate rotates around a hinged point, the included angle between the movable plate and the mounting plates is increased, so that the angle adjustment is realized; specifically, the laser mirror group is installed in the fly leaf outside, and motor and screw drive structure install in the fixed plate outside, and the linear motion output of screw drive structure passes and acts on the fly leaf behind the fixed plate, and along with the positive and negative rotation of motor, the linear motion output is reciprocal in the Y direction and is pushed away/pull the fly leaf (both can adopt the hard joint) for the articulated angle of two mounting panels changes, thereby has realized the angular adjustment of laser mirror group in the Y direction.
Claims (9)
1. An adaptive weld tracking method is characterized in that: the adopted welding seam tracking device comprises a laser lens group, a laser lens group angle adjusting mechanism and a diode laser generator, wherein a camera is arranged at the top of the laser lens group, and the diode laser generator is obliquely fixed at the front end of the laser lens group;
the welding joint aimed by the self-adaptive weld joint tracking is in angle joint or lap joint, and the corresponding workpiece comprises an upper plate and a lower plate;
the specific steps of the weld joint tracking are as follows:
(1) the diode laser generator obliquely emits laser beams, the laser beams fall on a workpiece and split in the X direction of a working plane, and the X direction is the tangential direction of a welding seam;
(2) the camera collects split images of the laser beams in real time and sends the images to the computer; each image comprises a split laser beam and a laser spot, the position of a welding seam is determined through the split position of the laser beam, and PV is defined as the coordinate value of the welding seam position of the previous image in the Y direction, namely the coordinate value of the current laser spot in the Y direction, by taking the edge of the upper laminate as a reference; defining SP as a coordinate value of the welding seam position of the current image in the Y direction; the Y direction is a direction perpendicular to a tangent of the welding seam on the working plane;
(3) defining the deviation value of the current laser spot and the target welding seam position in the Y direction as E, wherein E = SP-PV;
(4) converting the deviation into analog quantity, and transmitting the analog quantity to a laser mirror group angle adjusting mechanism;
(5) the laser lens group angle adjusting mechanism controls the laser lens group to change the angle in the Y direction, so that laser spots are adjusted to be in the correct welding position;
in the step (3) and the step (4), a camera is arranged to acquire images at the frequency of i frames per second, i deviation values in each second are summed, and the sum is multiplied by a controlled position proportionality coefficient K to obtain a voltage control signal
(ii) a Wherein E isjIs as followsjThe error distance between the laser spot and the target weld joint position in the frame image in the Y direction is more than or equal to 0j≤i1, k is a controlled position scaling factor determined at system calibration,which is related to the parameters of the angle adjusting mechanism of the laser mirror group.
2. The adaptive weld tracking method according to claim 1, wherein: the controlled position scaling factor K is determined by regression analysis of the measurement data.
3. The adaptive weld tracking method according to claim 1, wherein: the diode laser generator is fixed at the front end of the laser lens group by inclining 45 degrees through the connecting bracket.
4. The adaptive weld tracking method according to claim 1 or 3, wherein: the number of the diode laser generators is 2, the diode laser generators are respectively arranged on two sides of the front end of the laser mirror group and used for tracking welding seams in different welding directions.
5. The adaptive weld tracking method according to claim 1, wherein: the laser lens group angle adjusting mechanism comprises a servo motor, a screw rod transmission structure and a pair of hinged mounting plates; the laser lens group is arranged on one side of the mounting plate, and the servo motor and the screw rod transmission structure are arranged on the other side of the mounting plate; computer obtaining control signalU i And then, the servo motor is controlled to rotate, the screw rod transmission structure converts the rotary motion of the screw rod into linear motion to be output, the hinge angle of the pair of mounting plates is controlled to change, and the angle of the laser lens group is adjusted.
6. The adaptive weld tracking method according to claim 5, wherein: and two ends of the screw rod transmission structure are provided with limiting sensors for limiting the swing amplitude of the light spot position of the laser mirror group in the Y-axis direction.
7. The adaptive weld tracking method according to claim 1, wherein: the welding seam tracking device comprises an ST control box, a computer converts the deviation between the processed current laser spot position and the calibrated welding seam position into an analog quantity, outputs the analog quantity to the ST control box through a field bus EtherCAT protocol, then the ST control box transmits the analog quantity to a servo motor of the laser mirror group angle adjusting mechanism through the same field bus EtherCAT, and controls the angle of the laser mirror group through a screw rod transmission structure and a mounting plate.
8. The adaptive weld tracking method according to claim 7, wherein: and a power supply loop of a diode laser generator is arranged in the ST control box.
9. The adaptive weld tracking method according to claim 7, wherein: and a safety loop is arranged in the ST control box and is used for controlling the debugging/working state of the diode laser generator.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110460921.6A CN113146026B (en) | 2021-04-27 | 2021-04-27 | Self-adaptive welding seam tracking method |
| PCT/CN2022/084551 WO2022228027A1 (en) | 2021-04-27 | 2022-03-31 | Adaptive welding seam tracking method |
| ZA2023/08796A ZA202308796B (en) | 2021-04-27 | 2023-09-15 | Adaptive welding seam tracking method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110460921.6A CN113146026B (en) | 2021-04-27 | 2021-04-27 | Self-adaptive welding seam tracking method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113146026A CN113146026A (en) | 2021-07-23 |
| CN113146026B true CN113146026B (en) | 2022-04-26 |
Family
ID=76871481
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110460921.6A Active CN113146026B (en) | 2021-04-27 | 2021-04-27 | Self-adaptive welding seam tracking method |
Country Status (3)
| Country | Link |
|---|---|
| CN (1) | CN113146026B (en) |
| WO (1) | WO2022228027A1 (en) |
| ZA (1) | ZA202308796B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113146026B (en) * | 2021-04-27 | 2022-04-26 | 帕诺瓦智能科技(苏州)有限公司 | Self-adaptive welding seam tracking method |
| CN114633021B (en) * | 2022-03-02 | 2024-03-29 | 武汉逸飞激光股份有限公司 | Real-time vision acquisition laser welding method and device thereof |
Family Cites Families (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20120110513A (en) * | 2011-03-29 | 2012-10-10 | 신인승 | Self tracking laser welding apparatus |
| CN102513708B (en) * | 2011-11-25 | 2015-01-07 | 湖南大学 | Active type integrating device of micro-pore monitoring and seam tracking in short-wavelength laser welding |
| CN103203526A (en) * | 2012-01-16 | 2013-07-17 | 成都熊谷加世电器有限公司 | Laser visual tracking system |
| DE102013219220A1 (en) * | 2013-09-25 | 2015-03-26 | Bayerische Motoren Werke Aktiengesellschaft | Method for laser remote processing of a workpiece on a throat and device therefor |
| CN104057202B (en) * | 2014-07-11 | 2016-04-13 | 华南理工大学 | Based on the autonomous welding system of remote monitoring mobile robot and the method for FPGA |
| CN107824940A (en) * | 2017-12-07 | 2018-03-23 | 淮安信息职业技术学院 | Welding seam traking system and method based on laser structure light |
| CN107999955A (en) * | 2017-12-29 | 2018-05-08 | 华南理工大学 | A kind of six-shaft industrial robot line laser automatic tracking system and an automatic tracking method |
| CN108747132B (en) * | 2018-07-24 | 2020-06-23 | 襄阳市爱智瞳视觉科技有限公司 | Autonomous mobile welding robot vision control system |
| CN109175689B (en) * | 2018-09-27 | 2024-02-23 | 同高先进制造科技（太仓）有限公司 | Self-adaptive fillet welding system based on visual detection and working method |
| KR102591350B1 (en) * | 2018-12-13 | 2023-10-19 | 주식회사 성우하이텍 | Dynamic seam tracking device and laser welding system comprising same |
| CN109676243A (en) * | 2019-01-21 | 2019-04-26 | 苏州实创德光电科技有限公司 | Weld distinguishing and tracking system and method based on dual laser structure light |
| CN112958954B (en) * | 2021-02-03 | 2022-09-06 | 北京博清科技有限公司 | Welding seam tracking method and system |
| CN113146026B (en) * | 2021-04-27 | 2022-04-26 | 帕诺瓦智能科技(苏州)有限公司 | Self-adaptive welding seam tracking method |
-
2021
- 2021-04-27 CN CN202110460921.6A patent/CN113146026B/en active Active
-
2022
- 2022-03-31 WO PCT/CN2022/084551 patent/WO2022228027A1/en active Application Filing
-
2023
- 2023-09-15 ZA ZA2023/08796A patent/ZA202308796B/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| ZA202308796B (en) | 2023-11-29 |
| WO2022228027A1 (en) | 2022-11-03 |
| CN113146026A (en) | 2021-07-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113146026B (en) | Self-adaptive welding seam tracking method | |
| CN104057202B (en) | Based on the autonomous welding system of remote monitoring mobile robot and the method for FPGA | |
| CN110653460B (en) | Novel TIG welding device and welding method based on laser vision | |
| CN101961819A (en) | Device for realizing laser welding and seam tracking and control method thereof | |
| US20070075054A1 (en) | Display method for laser irradiations state and display system of laser irradiation state | |
| CN104175031A (en) | Welding robot with automatic correction function and welding method employing same | |
| CN111390351B (en) | Automatic welding device and welding method for real-time change of welding gun pose | |
| CN107262926B (en) | Automatic laser welding device with CCD detection function and welding method | |
| CN201514565U (en) | Laser weld seam tracking device | |
| CN202607049U (en) | Wheeled autonomously-moving welding robot control system with function of image monitoring | |
| CN114633021B (en) | Real-time vision acquisition laser welding method and device thereof | |
| CN203791807U (en) | Welding robot | |
| CN104588837A (en) | Intelligent coupling system of arc welding robot | |
| JP3191563B2 (en) | Automatic correction method for offline teaching data | |
| KR20210117307A (en) | Industrial robotic device with improved tooling path generation, and method for operating industrial robotic device according to improved tooling path | |
| CN109865919A (en) | A kind of real-time weld seam tracing system of right angle welding robot line laser | |
| TW200528755A (en) | Optical scanner control method, optical scanner and laser machining apparatus | |
| JP5577927B2 (en) | Laser processing detection system | |
| CN116197534A (en) | Laser welding method and laser welding processing technology | |
| CN204524507U (en) | Arc welding robot intelligence coupled system | |
| CN213318314U (en) | Multifunctional composite dynamic gantry stirring friction welding equipment | |
| JP3285256B2 (en) | Automatic alignment adjustment method and apparatus for laser robot | |
| CN112676726A (en) | Automatic welding device for lower side door and welding method and application thereof | |
| CN214867993U (en) | Laser lens group adjusting structure and welding seam tracking device with same | |
| CN114055021A (en) | Be applied to titanium steel combined material's intelligent welding set |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |