Arc welding robot locating system based on visual compensation

Abstract

The utility model belongs to the technical field of arc welding robots, and discloses an arc welding robot locating system based on visual difference compensation, which comprises a protective shell and an industrial personal computer which are arranged on an arc welding robot, a locating device is arranged in the protective shell, and an air inlet connector and an exhaust hole are oppositely arranged at the lower ends of two shell walls of the protective shell. The position searching device comprises a laser transmitter and a camera group; the laser transmitter, the first visual camera and the second visual camera are connected with the industrial personal computer through transmission lines; according to the utility model, the automatic tracking and positioning and error correction of the welding position are realized, the problem that the arc welding robot cannot finish the welding work of a non-standard workpiece is solved, the automation level of welding by using the robot in the welding industry is improved, and the use cost of a user is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of arc welding robots, in particular to an arc welding robot positioning system based on visual compensation. Background Art

[0002] With increasingly fierce market competition in recent years, manufacturers are increasingly focusing on improving welding productivity, ensuring product quality, and achieving automated and intelligent welding production. Consequently, welding robots with high precision, high efficiency, and high safety have emerged. Arc welding technology is a crucial component of modern welding technology, with applications spanning nearly all welding production areas.

[0003] In the Chinese utility model patent application number 201920733218.6, an integrated professional arc welding robot is proposed. This patent has the following main problems: First, in the welding field where the size error of some workpieces is relatively large or the fixture for fixing the workpiece is not accurate enough, the welding position changes greatly, so it is difficult for the arc welding robot to complete accurate welding operations, resulting in large errors after welding. Therefore, it is difficult for the arc welding robot to complete the welding of non-standard parts; second, the existing vision system or laser tracking system is expensive, even close to or exceeding the price of a welding robot. Utility Model Content

[0004] The main technical problem to be solved by the utility model is to provide an arc welding robot positioning system based on visual compensation, which realizes automatic tracking and positioning of the welding position and error correction, solves the problem that the arc welding robot cannot complete the welding of non-standard workpieces, improves the automation level of robot welding in the welding industry, and reduces the user's usage cost.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] An arc welding robot positioning system based on visual compensation includes a protective shell and an industrial control computer provided on the arc welding robot. A positioning device is provided inside the protective shell. An air inlet connector and an exhaust hole are provided at the lower ends of two shell walls of the protective shell.

[0007] The positioning device includes a laser transmitter and a camera group, and both the laser transmitter and the camera group are connected to the industrial computer through a transmission line.

[0008] The following is a further optimization of the above technical solution by the present invention:

[0009] The industrial computer is internally provided with a CPU controller, an image acquisition card, an image processing unit and a communication module. The transmission line is connected to the image acquisition card, and the CPU controller is communicated with the execution module of the arc welding robot through the communication module.

[0010] Further optimization: the camera group includes a first visual camera and a second visual camera.

[0011] Further optimization: A protective glass lens is provided at the bottom of the protective shell, and the lenses of the laser emitter, the first visual camera and the second visual camera are all set downward.

[0012] Further optimization: the image acquisition card is electrically connected to the image processing unit and the CPU controller.

[0013] Further optimization: the execution module includes an execution control unit and multiple joint motors. The execution control unit is communicatively connected to the CPU controller through the communication module, and each joint motor is electrically connected to the execution control unit.

[0014] Further optimization: the shooting direction of the first visual camera and the shooting direction of the second visual camera are arranged to be cross-set.

[0015] The utility model adopts the above technical solution, which has the following beneficial effects:

[0016] 1. Compared with traditional visual systems or laser tracking systems, the technical solution of this utility model utilizes the mutual cooperation of laser emitters, visual cameras and industrial computers to simplify the structure of the positioning system, achieve the purpose of simplicity and practicality, and also reduce the user's usage cost.

[0017] 2. The utility model uses a laser emitter and two visual cameras in combination to realize visual tracking detection of the welding position of the workpiece. The image captured by the visual camera is then transmitted to the industrial computer for imaging processing and calculation to obtain an intersection coordinate. The difference between the intersection coordinate and the center coordinate is transmitted to the arc welding robot. The robot will compensate the coordinate difference to the welding position of the manipulator, thereby controlling the manipulator to perform precise welding, solving the problem that the arc welding robot cannot complete the welding of non-standard workpieces, thereby improving the level of automation of robot welding in the welding industry.

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] 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 labor.

[0020] Figure 1 This is a schematic diagram of the overall structure in an embodiment of the present utility model;

[0021] Figure 2 This is a schematic diagram of a positioning system in an embodiment of the present utility model;

[0022] Figure 3 Schematic diagram of the laser measurement principle in an embodiment of the present utility model.

[0023] In the figure: 1-protective shell; 11-protective glass lens; 2-industrial computer; 21-CPU controller; 22-image acquisition card; 23-image processing unit; 24-communication module; 25-display; 3-positioning device; 31-laser transmitter; 32-camera group; 321-first vision camera; 322-second vision camera; 33-transmission line; 34-PROFINET industrial network cable; 35-power supply unit; 4-air inlet connector; 5-exhaust hole; 6-execution module; 61-execution control unit; 62-joint motor; 7-workpiece to be welded. DETAILED DESCRIPTION

[0024] 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 embodiments described 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 efforts are within the scope of protection of the present invention.

[0025] like Figure 1-Figure 3 As shown together, an arc welding robot positioning system based on visual compensation includes a protective shell 1 and an industrial computer 2 arranged on the arc welding robot, a positioning device 3 is arranged inside the protective shell 1, and an air inlet connector 4 and an exhaust hole 5 are relatively arranged at the lower ends of the two shell walls of the protective shell 1.

[0026] In this embodiment, the air inlet connector 4 is used to connect compressed air to the protective shell 1 .

[0027] In this embodiment, the introduction of compressed air plays two roles. On the one hand, it plays the role of air cooling, which can not only prevent the visual camera from being damaged by excessive temperature during welding, but also prevent welding slag from splashing onto the lens of the camera group 32 and the emitting lens of the laser emitter 31.

[0028] On the other hand, it plays a role in cleaning welding slag and dust on the lenses of the laser emitter 31, the first visual camera 321 and the second visual camera 322.

[0029] In this embodiment, welding slag and dust are discharged from the protective shell 1 through the exhaust holes 5 arranged opposite to each other.

[0030] In this embodiment, the setting of the positioning system can provide the arc welding robot with the precise welding position of non-standard workpieces, solve the problem that the arc welding robot cannot complete the welding of non-standard workpieces, and improve the automation level of robot welding in the welding industry.

[0031] In this embodiment, the positioning device 3 is arranged in the protective shell 1 and is not affected or disturbed by external environment such as light and temperature, which improves the measurement effect of the utility model and is suitable for operations in harsh environments such as welding sheet metal workpieces in non-standard automation projects.

[0032] like Figure 1 and Figure 2 As shown together, the positioning device 3 includes a laser emitter 31 and a camera group 32 , and both the laser emitter 31 and the camera group 32 are connected to the industrial computer 2 via a transmission line 33 .

[0033] In this embodiment, a red laser source is provided in the laser emitter 31 , and the red laser source is expanded into a line by an emission lens and irradiated onto the workpiece 7 to be welded.

[0034] In this embodiment, the laser line emitted by the laser emitter 31 irradiates the welding point of the workpiece 7 to be welded, forming two lines AB and CD. The two lines intersect at point E, which is the tracking point that the visual camera needs to detect.

[0035] In this embodiment, the first visual camera 321 and the second visual camera 322 are both 2D cameras.

[0036] In this embodiment, the first vision camera 321 detects the AB line, and the second vision camera 322 detects the CD line.

[0037] In this embodiment, the images detected by the first visual camera 321 and the second visual camera 322 are processed by an image processing algorithm to obtain the equations of the two straight lines AB and CD, and thus the coordinates of the point E can be obtained.

[0038] In this embodiment, the laser transmitter 31 communicates and exchanges data via the PROFINET industrial network cable 34 , and provides real-time feedback of error values ​​during operation. The scanning cycle is very short and the response is agile.

[0039] In this embodiment, a power supply unit 35 may be further provided in the protective shell 1 to supply power to the laser emitter 31 .

[0040] The camera group 32 includes a first vision camera 321 and a second vision camera 322 .

[0041] Among them, the industrial computer 2 is internally provided with a CPU controller 21, an image acquisition card 22, an image processing unit 23 and a communication module 24. The transmission line 33 is connected to the image acquisition card 22, and the CPU controller 21 is communicated with the execution module 6 of the arc welding robot through the communication module 24.

[0042] In this embodiment, the image processing unit 23 has built-in image processing software, which can perform image technology processing on pictures and video streams, analyze and calculate the spatial position information of the imaging target position points, and effectively handle problems such as image denoising and light interference in harsh environments, and adapt to different conditions in harsh environments.

[0043] In this embodiment, the image processing unit 23 can accurately calculate the coordinates of the intersection of the two reflected rays and can provide multiple sets of parameter settings to meet the welding requirements of thin plates and thick plates, with strong adaptability.

[0044] like Figure 1 As shown, a protective glass lens 11 is provided at the bottom of the protective shell 1 , and the lenses of the laser emitter 31 , the first visual camera 321 and the second visual camera 322 are all arranged downward and facing the protective glass lens 11 .

[0045] like Figure 2 As shown, the image acquisition card 22 is electrically connected to the image processing unit 23 and the CPU controller 21 .

[0046] In this embodiment, the image acquisition card 22 can also transmit the real-time images captured by the first visual camera 321 and the second visual camera 322 to the display 25 of the industrial computer 2 .

[0047] In this embodiment, the distance between the manipulator of the arc welding robot and the two workpieces 7 to be welded and their sequential or left-right positions determine the position where the laser beam is projected onto the visual camera, thus forming a two-dimensional measurement value.

[0048] In this embodiment, the image captured by the visual camera is calculated by image processing software to obtain the intersection coordinates of the laser broken lines.

[0049] Moreover, the execution module 6 includes an execution control unit 61 and a plurality of joint motors 62 . The execution control unit 61 is communicatively connected to the CPU controller 21 via the communication module 24 , and each joint motor 62 is electrically connected to the execution control unit 61 .

[0050] In this embodiment, the execution control unit 61 receives the intersection coordinate value uploaded by the CPU controller 21 and the difference between the coordinates of the remaining center points, and performs calculations to compensate the coordinate difference to the welding position of the robot.

[0051] This allows for error correction of the robot's welding, controls the robot for precise welding, and avoids welding errors.

[0052] In this embodiment, the arc welding robot includes six joint motors 62 , and the CPU controller 21 can control the six joint motors 62 to perform different command actions.

[0053] In this embodiment, the execution control unit 61 can also continuously provide data feedback to the CPU controller 21, thereby realizing real-time monitoring of the real-time data and position point data information of the manipulator itself.

[0054] The shooting direction of the first visual camera 321 and the shooting direction of the second visual camera 322 are arranged to intersect.

[0055] In this embodiment, the laser emitter 31 emits a laser beam for guidance, and the first visual camera 321 and the second visual camera 322 perform 2D photography and form a cross operation point.

[0056] The process of using the utility model to accurately locate the welding position is as follows:

[0057] In the first step, the laser emitter 31 emits a laser beam, which is irradiated onto the welding positions of the two workpieces 7 to be welded, forming an AB line and a CD line.

[0058] In the second step, the first visual camera 321 detects the AB line and takes a picture, and the second visual camera 322 detects the CD line and takes a picture. The images captured by the first visual camera 321 and the second visual camera 322 are transmitted to the image acquisition card 22 through the transmission line 33.

[0059] In the third step, the image acquisition card 22 transmits the image information to the CPU controller 21 and the image processing unit 23. The image processing unit 23 performs imaging processing on the received image information to obtain the coordinates of the intersection of the AB line and the CD line. The CPU controller 21 performs DSP data calculation to accurately calculate the error value of the target position point.

[0060] In the fourth step, the obtained intersection coordinate information and error value are transmitted to the execution control unit 61 of the arc welding robot execution module 6. The execution control unit 61 corrects the spatial coordinate position of the manipulator and calculates the spatial coordinate value of the manipulator after precise positioning. Then, the joint motor 62 is controlled to make different instructions to achieve precise welding of the two workpieces 7 to be welded.

[0061] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An arc welding robot positioning system based on visual compensation, characterized in that: It comprises a protective shell (1) and an industrial control computer (2) arranged on an arc welding robot, wherein a positioning device (3) is arranged inside the protective shell (1), and an air inlet joint (4) and an exhaust hole (5) are arranged opposite to each other at the lower ends of the two shell walls of the protective shell (1); The positioning device (3) comprises a laser emitter (31) and a camera group (32), and both the laser emitter (31) and the camera group (32) are connected to the industrial computer (2) via a transmission line (33).

2. The arc welding robot positioning system based on visual compensation according to claim 1 is characterized in that: The industrial computer (2) is internally provided with a CPU controller (21), an image acquisition card (22), an image processing unit (23) and a communication module (24); a transmission line (33) is connected to the image acquisition card (22); and the CPU controller (21) is in communication connection with the execution module (6) of the arc welding robot via the communication module (24).

3. The arc welding robot positioning system based on visual compensation according to claim 2 is characterized in that: The camera group (32) includes a first visual camera (321) and a second visual camera (322).

4. The arc welding robot positioning system based on visual compensation according to claim 3 is characterized in that: A protective glass lens (11) is provided at the bottom of the protective shell (1), and the lenses of the laser emitter (31), the first visual camera (321), and the second visual camera (322) are all arranged to face downward.

5. The arc welding robot positioning system based on visual compensation according to claim 2, characterized in that: The image acquisition card (22) is electrically connected to the image processing unit (23) and the CPU controller (21).

6. The arc welding robot positioning system based on visual compensation according to claim 2, characterized in that: The execution module (6) includes an execution control unit (61) and a plurality of joint motors (62). The execution control unit (61) is communicatively connected to the CPU controller (21) via the communication module (24), and each joint motor (62) is electrically connected to the execution control unit (61).

7. The arc welding robot positioning system based on visual compensation according to claim 3 is characterized in that: The shooting direction of the first visual camera (321) and the shooting direction of the second visual camera (322) are arranged to intersect.

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