Automatic robot welding spot detection device and detection method

Abstract

The automatic robot welding spot detection device comprises a collaborative robot mechanism, the collaborative robot mechanism comprises a base, a servo electric cylinder is installed at the top end of the base, and a first travel switch and a second travel switch are installed at the positions, located at the two ends of the servo electric cylinder, of the base correspondingly; the base is provided with an electric cylinder zero position sensor at the second travel switch; the servo electric cylinder drives a collaborative robot, a coupling agent liquid supply pump is installed at the bottom of the collaborative robot, an ultrasonic probe, a telescopic air cylinder and a visual camera are installed on a flange of an end effector of the collaborative robot, and a light source is installed at the position, located at the visual camera, of the collaborative robot. The telescopic air cylinder drives a coupling agent liquid supply pipe, and one end of the coupling agent liquid supply pipe is connected with a coupling agent liquid supply pump. The problem that in the prior art, due to the fact that the number of welding spot positions is large, the welding spot positions cannot be accurately determined, and therefore a coupling agent cannot be smeared is solved.

Description

Technical Field

[0001] The invention relates to the technical field of automobile component welding spot detection, in particular to an automatic robot welding spot automatic detection device and a detection method. Background Art

[0002] At present, the quality inspection methods of solder joints mainly include destructive inspection and non-destructive inspection. Destructive inspection is a mechanical destructive inspection method, which requires mechanical destruction of the solder joint. Defect detection is performed based on the material characteristics of the fracture surface. This type of inspection can only be carried out by spot check, and manual inspection is time-consuming and destructive. Non-destructive inspection is mainly ultrasonic inspection. Ultrasonic waves have strong penetrating power and will generate reflected waves at the edges of the upper and lower interfaces. By comparing the characteristics of the reflected waveforms, it is determined whether the solder joint has defects, and the nature, location and size of the defects are analyzed and determined to achieve detection; because ultrasonic inspection requires the coating of coupling agent; the coating process of the coupling agent is complicated, it is difficult to realize automatic inspection by robot clamping the probe.

[0003] Due to the large number of welding points on automotive parts, if we rely on manual judgment, the efficiency is very low; if we rely on automated detection, how to achieve accurate coating of coupling agent by robot and detection of robot probe is the technical problem we need to solve. To this end, we propose an automated robot welding point automatic detection device and detection method. Summary of the invention

[0004] The purpose of the present invention is to provide an automatic robot welding spot automatic detection device and detection method to solve the problems in the prior art.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an automatic robot welding point automatic detection device, including a collaborative robot mechanism, the collaborative robot mechanism including a base, a servo electric cylinder is installed on the top of the base, the base is respectively installed with a first travel switch and a second travel switch at both ends of the servo electric cylinder, and the base is installed with an electric cylinder zero position sensor at the second travel switch; the servo electric cylinder drives a collaborative robot, a coupling agent liquid supply pump is installed at the bottom of the collaborative robot, an ultrasonic probe, a telescopic cylinder and a visual camera are installed on the flange of the end effector of the collaborative robot, a camera light source is installed at the visual camera of the collaborative robot, the telescopic cylinder drives a coupling agent liquid supply pipe, and one end of the coupling agent liquid supply pipe is connected to the coupling agent liquid supply pump.

[0006] Preferably, it also includes a sled positioning mechanism, a first side panel fixture and a second side panel fixture, the first side panel fixture and the second side panel fixture are respectively located on both sides of the sled positioning mechanism, and there are two collaborative robot mechanisms in total, which are symmetrically distributed on both sides of the sled positioning mechanism, one of the collaborative robot mechanisms is located between the sled positioning mechanism and the first side panel fixture, and the other one of the collaborative robot mechanisms is located between the sled positioning mechanism and the second side panel fixture.

[0007] Preferably, the sled positioning mechanism includes a base frame, a cylinder frame and a sled; a plurality of positioning pin frames are installed on the top of the sled; a roller cooperating with the sled is installed on the top of the base frame, and guide wheels cooperating with the sled are installed on both sides of the base frame; two cylinder frames are symmetrically arranged on both sides of the base frame, and a first clamping cylinder and a second clamping cylinder cooperating with the positioning pin frames are respectively installed on the top of the two cylinder frames, and a first proximity switch and a second proximity switch are respectively installed on the top of the two cylinder frames.

[0008] Preferably, an eighth photoelectric sensor and a ninth photoelectric sensor are installed in the middle of one end of the base frame, a first photoelectric sensor, a second photoelectric sensor, a third photoelectric sensor, a fourth photoelectric sensor and a fifth photoelectric sensor are installed in sequence on one side of the other end of the base frame, a seventh photoelectric sensor corresponding to the second photoelectric sensor is installed on the other side of the base frame; a sixth photoelectric sensor is installed on one side of the sled, and through holes are provided at both ends of the sled.

[0009] Preferably, the first side panel fixture and the second side panel fixture both include a fixture frame, a plurality of bottom limit support frames are installed at the bottom of the fixture frame, a plurality of middle limit support frames are installed in the middle of the fixture frame, and a plurality of top limit support frames are installed at the top of the fixture frame.

[0010] Preferably, the first locating pin, the first clamping cylinder and the second clamping cylinder are installed at one end of the tooling frame, the fourth clamping cylinder, the fifth clamping cylinder, the sixth clamping cylinder, the seventh clamping cylinder and the eighth clamping cylinder are installed at the other end of the tooling frame, the twelfth photoelectric sensor is installed at the fourth clamping cylinder of the tooling frame, and the thirteenth photoelectric sensor is installed at the sixth clamping cylinder of the tooling frame; the third clamping cylinder, the second locating pin, the third locating pin, the eleventh photoelectric sensor, the fourth locating pin and the fifth locating pin are installed in the middle part of the tooling frame, and the tenth photoelectric sensor is installed below the third locating pin of the tooling frame.

[0011] Preferably, it also includes a PLC control cabinet, a collaborative robot control cabinet, a visual industrial computer, an ultrasonic industrial computer and an ultrasonic transceiver module. The collaborative robot control cabinet is composed of a robot control cabinet body and a teaching pendant. The collaborative robot control cabinet is connected to the electric collaborative robot, the collaborative robot control cabinet is electrically connected to the visual industrial computer, the visual industrial computer is electrically connected to the visual camera, the ultrasonic industrial computer is electrically connected to the ultrasonic transceiver module, the ultrasonic transceiver module is electrically connected to the ultrasonic probe, the PLC control cabinet is electrically connected to the servo electric cylinder, the collaborative robot control cabinet, the ultrasonic industrial computer, and the coupling agent supply pump respectively, and the visual camera adopts a 2D visual camera.

[0012] An automatic robot solder joint automatic detection method, using the automatic robot solder joint automatic detection device; comprising the following steps:

[0013] S1, PLC control cabinet turns on the equipment to run automatically;

[0014] S2, the collaborative robot drives the 2D vision camera to move to a reference position close to the solder joint to be inspected;

[0015] S3, the visual industrial computer controls the 2D visual camera to take pictures of the welding points and generate digital image information;

[0016] S4, after the 2D visual camera takes the photo, the digital image information of the welding point is transmitted to the visual industrial computer;

[0017] S5, the visual industrial computer calculates the position deviation of the welding point according to the digital image information of the welding point, and sends the deviation value to the collaborative robot control cabinet;

[0018] S6. The collaborative robot drives the coupling agent supply tube to move to a position close to the welding point;

[0019] S7, the coupling agent supply pump and the coupling agent supply tube squeeze out the coupling agent and apply it to the surface of the welding point;

[0020] S8, the collaborative robot control cabinet controls the collaborative robot to drive the ultrasonic probe to the precise position of the welding point according to the position deviation value fed back by the visual industrial computer;

[0021] S9, the ultrasonic industrial computer transmits ultrasonic signals, which act on the welding points through the ultrasonic probe;

[0022] S10, the welding point to be inspected reflects the ultrasonic signal, and after the ultrasonic probe receives the reflected signal, the weak ultrasonic signal is filtered and amplified by the ultrasonic transceiver module, and then transmitted to the ultrasonic industrial control computer;

[0023] S11, the ultrasonic industrial computer processes and calculates the ultrasonic echo signal and outputs the quality information of the tested solder joint;

[0024] S12. After executing the above steps, loop S2-S11 to perform quality inspection on the next solder joint to be tested.

[0025] Preferably, the visual industrial computer calculates the distance ΔL between the ultrasonic probe and the weld to be detected by processing the digital image information of the weld to be detected; including: performing region of interest extraction, denoising, edge detection, and circular contour fitting processing on the digital image to obtain the center point position of the circular contour of the weld to be detected; performing conversion from the pixel coordinate system to the collaborative robot coordinate system to obtain the coordinates of the center point in the collaborative robot coordinate system; and calculating the distance between the ultrasonic probe and the center point of the weld to be detected based on the coordinates of the ultrasonic probe in the collaborative robot coordinate system to obtain ΔL.

[0026] Preferably, in image processing, the area to be processed is outlined in the form of a square, circle, ellipse, or irregular polygon from the processed image, which is called region of interest extraction. The center point position of the circle outline is used as the position of the weld to be detected, and a conversion is performed from the pixel coordinate system to the collaborative robot coordinate system to obtain the coordinates of the center point in the collaborative robot coordinate system. Since the center point position obtained by image processing is only the relative position of the center point in the image, the coordinates of the center point in the collaborative robot coordinate system are calculated by coordinate transformation. The origin of the coordinate system is located at the center of the collaborative robot base, and includes six degrees of freedom, three of which are degrees of freedom for translation along three coordinate axes, and three are degrees of freedom for rotation around three coordinate axes. The distance between the ultrasonic probe and the center point is calculated based on its coordinates in the collaborative robot coordinate system.

[0027] The ultrasonic industrial computer evaluates the quality of the inspected solder joint by processing the ultrasonic echo signal; including: the ultrasonic industrial computer extracts the characteristic parameters of the ultrasonic echo signal of the inspected solder joint, compares it with the design parameters of the solder joint, and determines the quality of the solder joint to be inspected; the design parameters of the solder joint include: weld core diameter, indentation depth, and plate thickness after welding.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. The collaborative robot control cabinet is electrically connected to the visual industrial computer, which is electrically connected to the 2D visual camera. The 2D visual camera is installed on the flange of the collaborative robot's end effector. The visual industrial computer controls the 2D visual camera to take pictures of the welding points. The 2D visual camera transmits the welding point pictures to the visual industrial computer. The visual industrial computer calculates the welding point position deviation according to the picture taking results, and feeds back the deviation value to the collaborative robot control cabinet, thereby guiding the collaborative robot end to the precise position. This solves the problem in the prior art that there are many welding point positions and it is impossible to accurately determine the welding point positions, thus making it impossible to apply coupling agent.

[0030] 2. In image processing, outlining the area to be processed from the processed image in the form of a square, circle, ellipse, or irregular polygon is called region of interest extraction. Processing in the region of interest can reduce processing time and improve processing accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0032] Figure 1 It is a schematic diagram of the structure of the present invention;

[0033] Figure 2 It is a structural schematic diagram of the collaborative robot mechanism of the present invention;

[0034] Figure 3 The present invention Figure 2 Schematic diagram of the local structure;

[0035] Figure 4 It is a structural schematic diagram of the sled positioning mechanism of the present invention;

[0036] Figure 5 It is a structural schematic diagram of the side panel fixture of the present invention;

[0037] Figure 6 It is a schematic diagram of the present invention.

[0038] In the figure: 1. collaborative robot mechanism; 2. sled positioning mechanism; 3. first side enclosure fixture; 4. second side enclosure fixture; 101. base; 102. servo electric cylinder; 103. first stroke switch; 104. electric cylinder zero position sensor; 105. second stroke switch; 106. coupling agent liquid supply pump; 107. collaborative robot; 108. coupling agent liquid supply pipe; 109. telescopic cylinder; 110. ultrasonic probe; 111. camera light source; 112. visual camera; 201. chassis; 202. roller; 203. first photoelectric sensor; 204. second photoelectric sensor; 205. third photoelectric sensor; 206. fourth photoelectric sensor; 207. fifth photoelectric sensor; 208. sixth photoelectric sensor; 209. seventh photoelectric sensor; 210. positioning pin rack; 211. sled; 212. first clamping cylinder ; 213, the first proximity switch; 214, the eighth photoelectric sensor; 215, the ninth photoelectric sensor; 216, the second proximity switch; 217, the second clamping cylinder; 218, the guide wheel; 301, the tooling frame; 302, the top limit support frame; 303, the first positioning pin; 304, the first clamping cylinder; 305, the second clamping cylinder; 306, the bottom limit support frame; 307, the third clamping cylinder; 308, the second positioning pin; 309, the third positioning pin; 310, the tenth photoelectric sensor; 311, the eleventh photoelectric sensor; 312, the fourth positioning pin; 313, the fifth positioning pin; 314, the twelfth photoelectric sensor; 315, the fourth clamping cylinder; 316, the fifth clamping cylinder; 317, the sixth clamping cylinder; 318, the seventh clamping cylinder; 319, the eighth clamping cylinder; 320, the thirteenth photoelectric sensor. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, 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 described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention.

[0040] See also Figure 1-3In an embodiment of the present invention, an automatic robot welding spot automatic detection device includes a collaborative robot mechanism 1, the collaborative robot mechanism 1 includes a base 101, a servo electric cylinder 102 is installed on the top of the base 101, the base 101 is respectively installed with a first travel switch 103 and a second travel switch 105 at both ends of the servo electric cylinder 102, and the base 101 is installed with an electric cylinder zero position sensor 104 at the second travel switch 105; the servo electric cylinder 102 drives a collaborative robot 107, the bottom of the collaborative robot 107 is installed with a coupling agent supply pump 106, and the flange of the end effector of the collaborative robot 107 is installed with a Ultrasonic probe 110, telescopic cylinder 109 and visual camera 112, the collaborative robot 107 is located at the visual camera 112 and is equipped with a camera light source 111, the telescopic cylinder 109 drives a coupling agent supply tube 108, one end of the coupling agent supply tube 108 is connected to the coupling agent supply pump 106, and the coupling agent supply is realized through the coupling agent supply pump 106 and the coupling agent supply tube 108; the collaborative robot is a six-axis robot, which realizes six degrees of freedom of movement in the linear direction XYZ and the rotational direction UVW through the combination of six axes; the collaborative robot is installed on a servo electric cylinder, and the servo electric cylinder serves as the seventh axis of the robot to increase the reachable range of the robot end.

[0041] like Figure 1 ; It also includes a sled positioning mechanism 2, a first side panel fixture 3 and a second side panel fixture 4, the first side panel fixture 3 and the second side panel fixture 4 are respectively located on both sides of the sled positioning mechanism 2, and there are two collaborative robot mechanisms 1 in total, and the two collaborative robot mechanisms 1 are symmetrically distributed on both sides of the sled positioning mechanism 2, one of the collaborative robot mechanisms 1 is located between the sled positioning mechanism 2 and the first side panel fixture 3, and the other one of the collaborative robot mechanisms 1 is located between the sled positioning mechanism 2 and the second side panel fixture 4, and the first side panel fixture 3 and the second side panel fixture 4 are used to fix the left and right side panel inner panels.

[0042] like Figure 1 and 4The sled positioning mechanism 2 includes a base frame 201, a cylinder frame and a sled 211; a plurality of positioning pin frames 210 are installed on the top of the sled 211, and the positioning pin frames 210 are used to position the product; a roller 202 cooperating with the sled 211 is installed on the top of the base frame 201, and guide wheels 218 cooperating with the sled 211 are installed on both sides of the base frame 201, and the guide wheels 218 are used to guide the sled 211; two cylinder frames are symmetrically arranged on both sides of the base frame 201, and the first clamping cylinder 212 and the second clamping cylinder 217 cooperating with the positioning pin frames 210 are respectively installed on the top of the two cylinder frames, and the first clamping cylinder 212 and the second clamping cylinder 217 are used to lock one of the positioning pin frames 210 to facilitate the positioning of the sled 211, thereby For positioning of the product, a first proximity switch 213 and a second proximity switch 216 are respectively installed on the top of the two cylinder frames for sensing when the product is in place; an eighth photoelectric sensor 214 and a ninth photoelectric sensor 215 are installed in the middle of one end of the base frame 201, and a first photoelectric sensor 203, a second photoelectric sensor 204, a third photoelectric sensor 205, a fourth photoelectric sensor 206 and a fifth photoelectric sensor 207 are installed in sequence on one side of the other end of the base frame 201, and a seventh photoelectric sensor 209 corresponding to the second photoelectric sensor 204 is installed on the other side of the base frame 201; a sixth photoelectric sensor 208 is installed on one side of the sled 211, and through holes are provided at both ends of the sled 211 for connecting with an external driving mechanism to realize the movement of the sled 211.

[0043] like Figure 1 and 5The first side frame fixture 3 and the second side frame fixture 4 both include a fixture frame 301, a plurality of bottom limit support frames 306 are installed at the bottom of the fixture frame 301, a plurality of middle limit support frames are installed in the middle of the fixture frame 301, and a plurality of top limit support frames 302 are installed at the top of the fixture frame 301, and the product is supported by the bottom limit support frames 306, the middle limit support frames and the top limit support frames 302; a first positioning pin 303, a first clamping cylinder 304 and a second clamping cylinder 305 are installed at one end of the fixture frame 301, and a fourth clamping cylinder 315 is installed at the other end of the fixture frame 301. , the fifth clamping cylinder 316, the sixth clamping cylinder 317, the seventh clamping cylinder 318 and the eighth clamping cylinder 319, the twelfth photoelectric sensor 314 is installed at the fourth clamping cylinder 315 of the tooling frame 301, and the thirteenth photoelectric sensor 320 is installed at the sixth clamping cylinder 317 of the tooling frame 301; the third clamping cylinder 307, the second locating pin 308, the third locating pin 309, the eleventh photoelectric sensor 311, the fourth locating pin 312 and the fifth locating pin 313 are installed in the middle of the tooling frame 301, and the tenth photoelectric sensor 310 is installed on the tooling frame 301 below the third locating pin 309.

[0044] like Figure 6 ; It also includes a PLC control cabinet, a collaborative robot control cabinet, a visual industrial computer, an ultrasonic industrial computer and an ultrasonic transceiver module. The collaborative robot control cabinet is composed of a robot control cabinet body and a teaching pendant. The collaborative robot control cabinet is connected to the electric collaborative robot 107, the collaborative robot control cabinet is electrically connected to the visual industrial computer, the visual industrial computer is electrically connected to the visual camera 112, the ultrasonic industrial computer is electrically connected to the ultrasonic transceiver module, the ultrasonic transceiver module is electrically connected to the ultrasonic probe 110, the PLC control cabinet is electrically connected to the servo electric cylinder 102, the collaborative robot control cabinet, the ultrasonic industrial computer, and the coupling agent supply pump 106 respectively, and the visual camera 112 adopts a 2D visual camera.

[0045] The collaborative robot is a six-axis robot that realizes six degrees of freedom of movement in linear direction XYZ and rotational direction UVW through the combination of six axes; the collaborative robot is installed on a servo electric cylinder, which serves as the seventh axis of the robot to increase the reach of the robot end.

[0046] The collaborative robot control cabinet consists of a robot control cabinet body and a teach pendant. The collaborative robot is electrically connected to the collaborative robot control cabinet to realize control of the collaborative robot body. The teach pendant is used to control the collaborative robot body to perform trajectory teaching movements and control the movement trajectory of the end of the collaborative robot to make it close to the weld to be inspected, so as to obtain the reference position coordinates of the weld to be inspected; after the teaching is completed, the collaborative robot can move to the reference position of the weld to be inspected under the control of the collaborative robot control cabinet.

[0047] The collaborative robot control cabinet is electrically connected to the visual industrial computer, the visual industrial computer is electrically connected to the 2D visual camera, and the 2D visual camera is installed on the flange of the collaborative robot's end effector; the visual industrial computer controls the 2D visual camera to take pictures of the welding points, and the 2D visual camera transmits the welding point pictures to the visual industrial computer. The visual industrial computer calculates the welding point position deviation based on the picture taking results, and feeds back the deviation value to the collaborative robot control cabinet, thereby guiding the collaborative robot end to reach the precise position.

[0048] The ultrasonic industrial computer is electrically connected to the ultrasonic transceiver module, the ultrasonic transceiver module is electrically connected to the ultrasonic probe, and the ultrasonic probe is installed on the flange of the collaborative robot end effector; the ultrasonic industrial computer serves as a controller for ultrasonic signal transmission, reception and data processing; the ultrasonic transceiver module plays the role of ultrasonic signal transfer and amplification; the ultrasonic probe is attached to the surface of the weld as an ultrasonic actuator, transmits the ultrasonic signal generated by the ultrasonic industrial computer to the weld, and then receives the ultrasonic signal reflected by the weld, and finally feeds it back to the ultrasonic industrial computer through the ultrasonic transceiver module, and the ultrasonic industrial computer processes the ultrasonic signal reflected by the weld to obtain the weld quality result.

[0049] The PLC control cabinet is electrically connected to the servo electric cylinder, collaborative robot control cabinet, ultrasonic industrial computer, and coupling agent liquid supply device respectively; the PLC control cabinet serves as the overall equipment control, which uniformly controls all subordinate equipment. The equipment can be programmed in advance to realize automatic operation of the equipment.

[0050] An automatic robot solder joint automatic detection method, using the automatic robot solder joint automatic detection device; comprising the following steps:

[0051] S1, PLC control cabinet turns on the equipment to run automatically;

[0052] S2, the collaborative robot 107 drives the 2D vision camera to move to a reference position close to the welding point to be inspected;

[0053] S3, the visual industrial computer controls the 2D visual camera to take pictures of the welding points and generate digital image information;

[0054] S4, after the 2D visual camera takes the photo, the digital image information of the welding point is transmitted to the visual industrial computer;

[0055] S5, the visual industrial computer calculates the position deviation of the welding point according to the digital image information of the welding point, and sends the deviation value to the collaborative robot control cabinet;

[0056] S6, the collaborative robot 107 drives the coupling agent supply tube 108 to move to a position close to the welding point;

[0057] S7, the coupling agent supply pump 106 and the coupling agent supply pipe 108 squeeze the coupling agent out and apply it to the surface of the welding point;

[0058] S8, the collaborative robot control cabinet controls the collaborative robot 107 to drive the ultrasonic probe 110 to move to the precise position of the welding point according to the position deviation value fed back by the visual industrial computer;

[0059] S9, the ultrasonic industrial computer transmits an ultrasonic signal, which acts on the welding point through the ultrasonic probe 110;

[0060] S10, the welding point to be inspected reflects the ultrasonic signal, and after the ultrasonic probe 110 receives the reflected signal, the weak ultrasonic signal is filtered and amplified through the ultrasonic transceiver module, and then transmitted to the ultrasonic industrial control computer;

[0061] S11, the ultrasonic industrial computer processes and calculates the ultrasonic echo signal and outputs the quality information of the tested solder joint;

[0062] S12. After executing the above steps, loop S2-S11 to perform quality inspection on the next solder joint to be tested.

[0063] The visual industrial computer calculates the distance ΔL between the ultrasonic probe 110 and the weld point to be detected by processing the digital image information of the weld point to be detected; including: performing region of interest extraction, denoising, edge detection, and circle contour fitting processing on the digital image to obtain the center point position of the circle contour of the weld point to be detected; performing a conversion from a pixel coordinate system to a collaborative robot coordinate system to obtain the coordinates of the center point in the collaborative robot coordinate system; and calculating the distance between the ultrasonic probe 110 and the center point of the weld point to be detected based on the coordinates of the ultrasonic probe 110 in the collaborative robot coordinate system to obtain ΔL.

[0064] In image processing, the area to be processed is outlined in the form of a square, circle, ellipse, or irregular polygon from the processed image, which is called region of interest extraction. Processing in the region of interest can reduce processing time and improve processing accuracy. The center point of the circular outline is used as the position of the weld to be detected, and a conversion is performed from the pixel coordinate system to the collaborative robot coordinate system to obtain the coordinates of the center point in the collaborative robot coordinate system. Since the center point position obtained by image processing is only the relative position of the center point in the image, the coordinates of the center point in the collaborative robot coordinate system are calculated through coordinate transformation. The origin of the coordinate system is located at the center of the collaborative robot base, and includes six degrees of freedom, three of which are degrees of freedom for translation along three coordinate axes, and three are degrees of freedom for rotation around three coordinate axes. The distance between the ultrasonic probe 110 and the center point is calculated based on its coordinates in the collaborative robot coordinate system.

[0065] The ultrasonic industrial computer evaluates the quality of the inspected solder joint by processing the ultrasonic echo signal; including: the ultrasonic industrial computer extracts the characteristic parameters of the ultrasonic echo signal of the inspected solder joint, compares it with the design parameters of the solder joint, and determines the quality of the solder joint to be inspected; the design parameters of the solder joint include: weld core diameter, indentation depth, and plate thickness after welding.

[0066] Originally, it took 12 people to do this job, the labor intensity was high, and the consistency of manual operation could not be guaranteed. After switching to full automatic, manual operation was completely replaced, the measurement accuracy was higher, and the results were more accurate.

[0067] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An automated robot welding spot automatic detection device, comprising a collaborative robot mechanism (1), characterized in that: The collaborative robot mechanism (1) comprises a base (101), a servo electric cylinder (102) is mounted on the top of the base (101), a first travel switch (103) and a second travel switch (105) are mounted on the two ends of the servo electric cylinder (102) of the base (101), and an electric cylinder zero position sensor (104) is mounted on the base (101) at the second travel switch (105); the servo electric cylinder (102) drives a collaborative robot (107), and the collaborative robot ( A coupling agent liquid supply pump (106) is installed at the bottom of the collaborative robot (107); an ultrasonic probe (110), a telescopic cylinder (109) and a visual camera (112) are installed on the flange of the end effector of the collaborative robot (107); a camera light source (111) is installed at the visual camera (112) of the collaborative robot (107); the telescopic cylinder (109) drives a coupling agent liquid supply pipe (108); one end of the coupling agent liquid supply pipe (108) is connected to the coupling agent liquid supply pump (106).

2. The automatic robot welding spot automatic detection device according to claim 1 is characterized in that: It also includes a sled positioning mechanism (2), a first side panel fixture (3) and a second side panel fixture (4), wherein the first side panel fixture (3) and the second side panel fixture (4) are respectively located on both sides of the sled positioning mechanism (2), and there are two collaborative robot mechanisms (1) in total, which are symmetrically distributed on both sides of the sled positioning mechanism (2), one of the collaborative robot mechanisms (1) is located between the sled positioning mechanism (2) and the first side panel fixture (3), and the other one of the collaborative robot mechanisms (1) is located between the sled positioning mechanism (2) and the second side panel fixture (4).

3. The automatic robot welding spot automatic detection device according to claim 2 is characterized in that: The sled positioning mechanism (2) comprises a base frame (201), a cylinder frame and a sled (211); a plurality of positioning pin frames (210) are installed on the top of the sled (211); a roller (202) matching with the sled (211) is installed on the top of the base frame (201), and guide wheels (218) matching with the sled (211) are installed on both sides of the base frame (201); two cylinder frames are symmetrically arranged on both sides of the base frame (201), a first clamping cylinder (212) and a second clamping cylinder (217) matching with the positioning pin frames (210) are installed on the top of the two cylinder frames, and a first proximity switch (213) and a second proximity switch (216) are installed on the top of the two cylinder frames.

4. The automatic robot welding spot automatic detection device according to claim 3 is characterized in that: An eighth photoelectric sensor (214) and a ninth photoelectric sensor (215) are installed in the middle of one end of the base frame (201); a first photoelectric sensor (203), a second photoelectric sensor (204), a third photoelectric sensor (205), a fourth photoelectric sensor (206) and a fifth photoelectric sensor (207) are installed in sequence on one side of the other end of the base frame (201); a seventh photoelectric sensor (209) corresponding to the second photoelectric sensor (204) is installed on the other side of the base frame (201); a sixth photoelectric sensor (208) is installed on one side of the sled (211); and through holes are provided at both ends of the sled (211).

5. The automatic robot welding spot automatic detection device according to claim 1 is characterized in that: The first side panel fixture (3) and the second side panel fixture (4) both comprise a fixture frame (301), a plurality of bottom limit support frames (306) being mounted at the bottom of the fixture frame (301), a plurality of middle limit support frames being mounted at the middle of the fixture frame (301), and a plurality of top limit support frames (302) being mounted at the top of the fixture frame (301).

6. The automatic robot welding spot automatic detection device according to claim 5 is characterized in that: A first positioning pin (303), a first clamping cylinder (304) and a second clamping cylinder (305) are installed at one end of the tooling frame (301); a fourth clamping cylinder (315), a fifth clamping cylinder (316), a sixth clamping cylinder (317), a seventh clamping cylinder (318) and an eighth clamping cylinder (319) are installed at the other end of the tooling frame (301); a twelfth photoelectric sensor (314) is installed at the fourth clamping cylinder (315) of the tooling frame (301) The tooling frame (301) is provided with a thirteenth photoelectric sensor (320) at the sixth clamping cylinder (317); the third clamping cylinder (307), the second positioning pin (308), the third positioning pin (309), the eleventh photoelectric sensor (311), the fourth positioning pin (312) and the fifth positioning pin (313) are installed in the middle of the tooling frame (301); and the tenth photoelectric sensor (310) is installed below the third positioning pin (309) on the tooling frame (301).

7. An automatic robot welding spot automatic detection device according to any one of claims 1 to 6, characterized in that: It also includes a PLC control cabinet, a collaborative robot control cabinet, a visual industrial computer, an ultrasonic industrial computer and an ultrasonic transceiver module. The collaborative robot control cabinet is composed of a robot control cabinet body and a teaching pendant. The collaborative robot control cabinet is connected to the electric collaborative robot (107), the collaborative robot control cabinet is electrically connected to the visual industrial computer, the visual industrial computer is electrically connected to the visual camera (112), the ultrasonic industrial computer is electrically connected to the ultrasonic transceiver module, the ultrasonic transceiver module is electrically connected to the ultrasonic probe (110), the PLC control cabinet is electrically connected to the servo electric cylinder (102), the collaborative robot control cabinet, the ultrasonic industrial computer, and the coupling agent supply pump (106), respectively, and the visual camera (112) is a 2D visual camera.

8. An automatic robot solder joint automatic detection method, characterized in that: The automatic robot welding spot automatic detection device according to any one of claims 1 to 7 is used; comprising the following steps: S1, PLC control cabinet turns on the equipment to run automatically; S2, the collaborative robot (107) drives the 2D vision camera to move to a reference position close to the welding point to be inspected; S3, the visual industrial computer controls the 2D visual camera to take pictures of the welding points and generate digital image information; S4, after the 2D visual camera takes the photo, the digital image information of the welding point is transmitted to the visual industrial computer; S5, the visual industrial computer calculates the position deviation of the welding point according to the digital image information of the welding point, and sends the deviation value to the collaborative robot control cabinet; S6. The collaborative robot (107) drives the coupling agent supply pipe (108) to move to a position close to the welding point; S7, the coupling agent liquid supply pump (106) and the coupling agent liquid supply pipe (108) squeeze out the coupling agent and apply it to the surface of the welding point; S8, the collaborative robot control cabinet controls the collaborative robot (107) to drive the ultrasonic probe (110) to move to the precise position of the welding point according to the position deviation value fed back by the visual industrial control computer; S9, the ultrasonic industrial computer transmits an ultrasonic signal, which acts on the welding point through the ultrasonic probe (110); S10, the welding point to be inspected reflects an ultrasonic signal, and after the ultrasonic probe (110) receives the reflected signal, the weak ultrasonic signal is filtered and amplified through the ultrasonic transceiver module, and then transmitted to the ultrasonic industrial control computer; S11, the ultrasonic industrial computer processes and calculates the ultrasonic echo signal and outputs the quality information of the tested solder joint; S12. After executing the above steps, loop S2-S11 to perform quality inspection on the next solder joint to be tested.

9. The method for automatic detection of solder joints by an automated robot according to claim 8, characterized in that: The visual industrial computer processes digital image information of the weld to be detected to calculate the distance ΔL between the ultrasonic probe (110) and the weld to be detected; the method comprises: performing interest region extraction, denoising, edge detection, and circular contour fitting processing on the digital image to obtain the center point position of the circular contour of the weld to be detected; performing conversion from a pixel coordinate system to a collaborative robot coordinate system to obtain the coordinates of the center point in the collaborative robot coordinate system; and calculating the distance between the ultrasonic probe (110) and the center point of the weld to be detected according to the coordinates of the ultrasonic probe (110) in the collaborative robot coordinate system to obtain ΔL.

10. The automatic robot solder joint automatic detection method according to claim 9, characterized in that: In image processing, the area to be processed is outlined in the form of a square, circle, ellipse, or irregular polygon from the processed image, which is called region of interest extraction. The center point position of the circle outline is used as the position of the weld to be detected, and a transformation is performed from the pixel coordinate system to the collaborative robot coordinate system to obtain the coordinates of the center point in the collaborative robot coordinate system. Since the center point position obtained by image processing is only the relative position of the center point in the image, the coordinates of the center point in the collaborative robot coordinate system are calculated through coordinate transformation. The origin of the coordinate system is located at the center of the collaborative robot base, and includes six degrees of freedom, three of which are degrees of freedom for translation along three coordinate axes and three of which are degrees of freedom for rotation around three coordinate axes. The distance between the ultrasonic probe (110) and the center point is calculated based on the coordinates of the ultrasonic probe (110) in the collaborative robot coordinate system. The ultrasonic industrial computer evaluates the quality of the inspected solder joint by processing the ultrasonic echo signal; including: the ultrasonic industrial computer extracts the characteristic parameters of the ultrasonic echo signal of the inspected solder joint, compares it with the design parameters of the solder joint, and determines the quality of the solder joint to be inspected; the design parameters of the solder joint include: weld core diameter, indentation depth, and plate thickness after welding.

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