Intelligent steel rail welding seam scanning device and method based on cooperation of double mechanical arms

Abstract

The invention belongs to the technical field of steel rail ultrasonic detection, and discloses an intelligent steel rail welding seam scanning device and method based on cooperation of double mechanical arms, the intelligent steel rail welding seam scanning device comprises a trolley, the trolley comprises a supporting platform, and supporting frames in the vertical direction are symmetrically fixed to the front end and the rear end of the supporting platform; a locking mechanism is arranged at the bottom of at least one supporting frame; an acquisition box and a flaw detector are mounted at the top of the supporting platform; guide rails are longitudinally fixed at the bottom of the supporting platform along the steel rails; mechanical arms capable of sliding along the guide rail are symmetrically arranged on the left side and the right side of the guide rail respectively; a 70-degree probe, a 0-degree probe and a 45-degree probe are integrated at the tail end of each mechanical arm. According to the intelligent steel rail welding seam scanning device based on cooperation of the double mechanical arms, the traditional operation mode that welding seam flaw detection is conducted manually is replaced, automation of flaw detection is achieved, the labor intensity of flaw detection personnel is reduced, and the precision and efficiency of welding seam flaw detection are improved.

Description

Technical Field

[0001] This invention relates to the field of ultrasonic testing technology, specifically to an intelligent rail weld inspection device and method based on dual robotic arm collaboration. Background Technology

[0002] With the development of railway transportation and the growth in demand, rail welding technology has been widely used in railway construction. The quality of the weld formed after rail welding has a very important impact on the safety, reliability, and economic benefits of railway transportation. Because rail welds differ from cast iron and cast steel components, their fracture can lead to fatal damage in a short period, resulting in railway accidents. Therefore, rail weld flaw detection has become one of the important means to ensure railway traffic safety.

[0003] Currently, rail weld flaw detection methods mainly rely on manual probe operation, which has the following shortcomings: 1. Complex procedures, long processing time, and low efficiency. According to existing flaw detection process requirements, on-site weld inspection requires the use of multiple rail probe channels from different rail locations to inspect the entire weld cross-section. Switching between multiple probes and scanning methods results in a single weld flaw detection taking more than 10 minutes, leading to high labor costs and significant pressure on anti-failure work; 2. Low accuracy of flaw detection data. Due to manual scanning, the probe position, path, angle, and scanning range cannot be consistent each time, resulting in high operational errors, poor data consistency, and the flaw detection effect being directly related to the professional level of the flaw detector operator, easily leading to misjudgments and omissions; 3. Flaw detection data is not conducive to analysis, and the process lacks supervision. Unlike base material flaw detection, weld flaw detection data is mostly A-mode waveform data. During later analysis, it is impossible to fully view the detected area and the effectiveness of the detection, and frame-by-frame playback is required, making analysis difficult and time-consuming. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides an intelligent rail weld inspection device and method based on dual robotic arm collaboration, which can effectively solve the above-mentioned problems.

[0005] The technical solution adopted in this invention is as follows:

[0006] The present invention provides an intelligent rail weld inspection device based on dual robotic arm collaboration, including a handcart (4), the handcart (4) including a support platform (401), the support platform (401) having symmetrically fixed vertical support frames (402) at both ends of the front and rear; a rail wheel (11) is provided at the bottom center of each support frame (402); and a locking mechanism (6) is provided at the bottom of at least one support frame (402).

[0007] The top of the support platform (401) is equipped with a data acquisition box (1) and a flaw detector (3); the bottom of the support platform (401) is fixed with a guide rail (7) along the longitudinal direction of the rail; on the left and right sides of the guide rail (7), there are symmetrically arranged robotic arms (9) that can slide along the guide rail (7); each robotic arm (9) has a 70° probe (12), a 0° probe (13) and a 45° probe (14) integrated at its end; each robotic arm (9) is equipped with an independent drive mechanism; the rail data detected by each probe is transmitted to the data acquisition box (1); the data acquisition box (1) is connected to the flaw detector (3) and is displayed through the flaw detector (3).

[0008] Furthermore, two first centering devices (2) are installed on the top of the support platform (401); a second centering device (8) is installed in the middle of the bottom surface of the guide rail (7).

[0009] The two first centering devices (2) emit two laser beams. When the two laser beams are close to and parallel to the two sides of the rail being tested, and at the same time the cross-shaped laser beam emitted by the second centering device (8) is at the center of the rail being tested, it indicates that the intelligent rail weld inspection device based on the collaboration of two robotic arms has completed centering.

[0010] Furthermore, a lifting handle (10) is installed on the top surface and on each of the left and right sides of the support platform (401); a push handle (5) is provided on the rear side of the support platform (401).

[0011] Furthermore, the locking mechanism (6) includes a spring (601), a handle (602), a connecting block (603), a mounting bracket (604), a housing (605), a gripper (606), an elliptical rotating shaft (607), a tension spring (608), a buffer pad (609), a fixing block (610), a semi-circular screw rod (611), a connecting arm (612), a fixing shaft (613), and a rotating shaft (614).

[0012] The mounting bracket (604) is fixed to the support frame (402); each side of the mounting bracket (604) is rotatably connected to the top of a connecting arm (612); a plurality of fixed shafts (613) are fixed between the two connecting arms (612); one end of the spring (601) is fixed to the top of the mounting bracket (604), and the other end of the spring (601) is hung on the outer periphery of a fixed shaft (613); the spring (601) provides the connecting arm (612) with the rotational force to rotate upward relative to the mounting bracket (604);

[0013] The bottom of the two connecting arms (612) clamps and fixes the connecting block (603); the bottom of the connecting block (603) fixes the outer shell (605); the two sides of the outer shell (605) are rotatably and symmetrically mounted with the grippers (606) through the pivot (614); the two grippers (606) are connected by the tension spring (608), and the connection point of the tension spring (608) with each gripper (606) is located above the pivot (614); through the tension spring (608), the tops of the two grippers (606) tend to move closer together, and the bottoms tend to move further apart;

[0014] An elliptical shaft (607) is disposed between the two grippers (606); the threaded rod of the handle (602) passes through the connecting block (603) and then through the center of the elliptical shaft (607), and is fixed to the fixing block (610) located below the elliptical shaft (607); when the handle (602) rotates, it drives the elliptical shaft (607) to rotate synchronously;

[0015] A horizontally oriented semi-circular screw rod (611) is fixed to the inner side of each of the grippers (606); a buffer pad (609) is provided on the inner bottom side of each of the grippers (606).

[0016] When the handle (602) drives the elliptical shaft (607) to rotate to the minimum lateral position along the clamping direction of the two clamping claws (606), under the tension of the tension spring (608), the tops of the two clamping claws (606) move closer together and the bottoms move further apart, and the end faces of the two semi-circular screw rods (611) abut against the two sides of the elliptical shaft (607), which is the loosened state;

[0017] When the handle (602) drives the elliptical shaft (607) to rotate to the maximum lateral position along the clamping direction, during the rotation of the elliptical shaft (607), the two sides of the elliptical shaft (607) push the semi-circular screw rod (611) outward, thereby causing the jaws (606) on both sides to overcome the tension of the tension spring (608) and rotate around the shaft (614) connected to the outer shell (605), thereby causing the tops of the jaws (606) on both sides to move away and the bottoms to move closer. When the elliptical shaft (607) rotates to the maximum lateral position, the bottoms of the jaws (606) on both sides clamp the two sides of the rail, which is the locked state.

[0018] Furthermore, let the longitudinal direction of the rail be X-direction, the width direction of the rail be Y-direction, and the vertical direction be Z-direction; each of the robotic arms (9) includes a slider (901), a base (902), a first connecting arm (903), a second connecting arm (904), a third connecting arm (905), and 5 servo motors;

[0019] One end of the base (902) is fixed to the slider (901), and the slider (901) is slidably mounted on one side of the guide rail (7). Under the drive of the first servo motor, it slides along the guide rail (7) in the X direction. The other end of the base (902) is connected to one end of the first connecting arm (903) through the second servo motor. The rotation axis of the second servo motor is in the X direction, which is used to drive the first connecting arm (903) to rotate around its X axis, thereby adjusting the Y and Z positions.

[0020] The other end of the first connecting arm (903) is connected to one end of the second connecting arm (904) via a third servo motor; the rotation axis of the third servo motor is in the X direction, which is used to drive the second connecting arm (904) to rotate around its X axis, thereby adjusting the Y and Z positions;

[0021] The other end of the second connecting arm (904) is connected to the side of the third connecting arm (905) via a fourth servo motor; the rotation axis of the fourth servo motor is in the X direction, which is used to drive the third connecting arm (905) to rotate 360 ​​degrees around its X axis;

[0022] One end of the third connecting arm (905) is fixed with the 0° probe (13) and the 45° probe (14) in sequence; the other end of the third connecting arm (905) is provided with a fifth servo motor; the rotation axis of the fifth servo motor is Z-axis, and the output end of the fifth servo motor is equipped with the 70° probe (12) for driving the 70° probe (12) to rotate 360 ​​degrees around its Z-axis.

[0023] The present invention also provides a method for the intelligent rail weld inspection device based on dual robotic arm collaboration, comprising the following steps:

[0024] Step S1: Adjust the locking mechanism (6) to the loose state by using the handle (602). Under the elastic force of the spring (601), the connecting arm (612) rotates upward around the hinge point with the mounting bracket (604), thereby causing the outer shell (605) and all the parts assembled to the outer shell (605) to rotate upward and move away from the rail.

[0025] Step S2, push the handcart (4) to move the rail wheel (11) along the rail to the weld area to be probed;

[0026] Step S3: Start the first alignment device (2) and the second alignment device (8) to complete the alignment check operation;

[0027] Step S4: Press the outer shell (605) down with external force to make the connecting arm (612) rotate downward around the hinge point with the mounting bracket (604) and make the outer shell (605) vertical; then operate the handle (602) to adjust the locking mechanism (6) to the locking state.

[0028] Step S5: Coordinate the control of the two robotic arms (9) to make them reciprocate and repeatedly scan and detect the weld area.

[0029] The detected weld quality data is transmitted in real time to the flaw detector (3) through the acquisition box (1). After being analyzed and processed by the flaw detector (3), it is displayed in the form of waveform.

[0030] Step S6: After completing the current weld area scan, return to step S1, use handle (602) to adjust the locking mechanism (6) to the loose state, and push the trolley (4) to the next weld area for scanning.

[0031] Furthermore, step S5 specifically involves:

[0032] By controlling the coordinated motion mode of the dual robotic arms and the working mode of the probes, at least eight scanning methods are integrated to target different areas and defect orientations of rail welds. Specific scanning methods include:

[0033] ① Rail Bottom 70° Probe Scanning Method: Control the two robotic arms (9) to move synchronously, so that the 70° probes (12) at their ends are in single-fire and single-receive mode, and symmetrically scan the rail bottom area from the two inclined surfaces of the bottom of the rail to detect transverse crack defects at the rail bottom;

[0034] ② Rail head 70° probe scanning method: Control the movement of the left robotic arm (9) so that the 70° probe (12) at its end can scan the rail head area from the top surface of the rail head tread to detect defects inside the rail head;

[0035] ③ 0° probe scanning method: control the movement of the left robotic arm (9) so that the 0° probe (13) at its end is placed from the rail head tread. The 0° probe (13) adopts a 0° dual crystal probe, one transmitting and one receiving, and uses its sound beam characteristics to perform vertical or small angle scanning of the longitudinal area from the rail head, rail web to the rail bottom, and detect defects that are roughly parallel to the tread.

[0036] ④ 45° probe scanning method: Control the movement of the left robotic arm (9) so that the single 45° probe (14) at its end emits ultrasonic waves from the rail head tread at a fixed refraction angle to scan the area extending from the rail web to the rail bottom and detect defects with a certain tilt angle.

[0037] ⑤ Rail head tandem K-type scanning method: control the left robotic arm (9) as the transmitting unit and the right robotic arm (9) as the receiving unit. The 45° probes (14) at the ends of the two robotic arms (9) are placed opposite each other from the two sides of the rail head to form a K-type sound path. By synchronously moving the two robotic arms, the rail head is scanned in a penetrating manner, which is suitable for detecting vertical or tilting defects inside the rail head.

[0038] ⑥ Track bottom tandem K-type scanning method: Control the left robotic arm (9) as the transmitting unit and the right robotic arm (9) as the receiving unit. The 45° probes (14) at the ends of the two robotic arms (9) move to the two sides of the track bottom to perform K-type scanning on the track bottom position to detect internal defects in the track bottom area.

[0039] ⑦ Rail web front tandem scanning method: Control the left and right robotic arms (9) as transmitting and receiving units respectively, place the 45° probes (14) on the rail head tread and on the same side of the weld center line, in front or on the left, arrange the two probes in a tandem arrangement, one in front and one behind, and move along the longitudinal direction of the rail to detect vertical defects in the front half of the weld, that is, the area close to the scanning start side and the rail web area;

[0040] ⑧ Rail web tandem scanning method: Control the left and right robotic arms (9) as transmitting and receiving units respectively, place the 45° probes (14) on the rail head tread and on the same side of the weld center line, behind or to the right. The two probes are arranged in tandem, one in front and one behind, and move along the longitudinal direction of the rail to detect vertical defects in the front half of the weld, that is, the area close to the scanning start side and the rail web area.

[0041] The intelligent rail weld inspection device and method based on dual robotic arm collaboration provided by this invention has the following advantages:

[0042] This invention discloses an intelligent rail weld inspection device based on dual robotic arm collaboration, which replaces the traditional manual weld flaw detection operation mode, realizes the automation of flaw detection, reduces the labor intensity of flaw detection personnel, and improves the accuracy and efficiency of weld flaw detection. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 The front view of the intelligent rail weld inspection device based on dual robotic arm collaboration provided by the present invention;

[0045] Figure 2 A perspective view of the intelligent rail weld inspection device based on dual robotic arm collaboration provided by the present invention;

[0046] Figure 3 A side view of the locking mechanism provided by the present invention;

[0047] Figure 4 A perspective view of the locking mechanism provided by the present invention;

[0048] Figure 5 A perspective view of the locking mechanism with its concealed housing provided by the present invention;

[0049] Figure 6 An assembly diagram of the gripper and the semi-circular screw rod provided for this invention;

[0050] Figure 7 A three-dimensional view of the assembled robotic arm and probe provided by the present invention;

[0051] Figure 8 This is a perspective view of the robotic arm and probe after assembly, taken from another angle, as provided by the present invention.

[0052] Wherein: 1-Data acquisition box; 2-First alignment device; 3-Flaw detector; 4-Trolley; 5-Push handle; 6-Locking mechanism; 7-Guide rail; 8-Second alignment device; 9-Robotic arm; 10-Lifting hand; 11-Land rail wheel; 12-70° probe; 13-0° probe; 14-45° probe;

[0053] 601-Spring; 602-Handle; 603-Connecting block; 604-Mounting bracket; 605-Housing shell; 606-Gripper; 607-Oval rotating shaft; 608-Tension spring; 609-Buffer pad; 610-Fixing block; 611-Semi-circular screw rod; 612-Connecting arm; 613-Fixing shaft; 614-Rotating shaft; 901-Slider; 902-Base; 903-First connecting arm; 904-Second connecting arm; 905-Third connecting arm; A-Second servo motor; B-Third servo motor; C-Fourth servo motor; D-Fifth servo motor. Detailed Implementation

[0054] To make the technical problems solved, the technical solutions, and the beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the invention.

[0055] See Figures 1-8 This invention provides an intelligent rail weld inspection device based on dual robotic arm collaboration, comprising a handcart 4, the handcart 4 including a support platform 401, and symmetrically fixed vertical support frames 402 at both ends of the support platform 401; each support frame 402 has a land rail wheel 11 at its bottom center; the land rail wheel 11 can be used to push the inspection device on land or on the rail, achieving dual-purpose use. At least one of the support frames 402 has a locking mechanism 6 at its bottom;

[0056] The top of the support platform 401 is equipped with a data acquisition box 1 and a flaw detector 3; the data acquisition box 1 is connected to the flaw detector 3 via a wiring harness.

[0057] The bottom of the support platform 401 is fixed with a guide rail 7 along the longitudinal direction of the rail. Symmetrically arranged on the left and right sides of the guide rail 7 are sliding robotic arms 9. Each robotic arm 9 integrates a 70° probe 12, a 0° probe 13, and a 45° probe 14 at its end. Each robotic arm 9 is equipped with an independent drive mechanism. The rail data detected by each probe is transmitted to the acquisition box 1. The acquisition box 1 is connected to the flaw detector 3, and the data is displayed through the flaw detector 3. For example, after analysis and processing by the flaw detector 3, the data is displayed in waveform form.

[0058] To facilitate the movement and use of the trolley 4, a lifting handle 10 is installed on the top surface and on each of the left and right sides of the support platform 401; this allows one person or two people to lift the flaw detection device, making it convenient to move the instrument up and down the track, i.e., making it easy for staff to move the instrument or remove it from the track. A push handle 5 is provided on the rear side of the support platform 401 to push the scanning device.

[0059] As one embodiment, two first centering devices 2 are installed on the top of the support platform 401; a second centering device 8 is installed in the middle of the bottom surface of the guide rail 7; the two first centering devices 2 emit two laser beams. When the two laser beams are close to and parallel to the two sides of the rail being tested, and at the same time the cross-shaped laser beam emitted by the second centering device 8 is at the center of the rail being tested, it indicates that the intelligent rail weld inspection device based on dual robotic arm collaboration has completed centering and can proceed to the next step.

[0060] In this invention, one or two locking mechanisms 6 can be provided. After the instrument is placed on the rail and aligned, the locking mechanism 6 is used to fix and lock the instrument on the rail. The instrument then begins the scanning task. After the flaw detection is completed, the locking mechanism 6 is released, and the operator can drag the scanning device to the next weld.

[0061] See Figures 3-6 The locking mechanism 6 includes a spring 601, a handle 602, a connecting block 603, a mounting bracket 604, a housing 605, a gripper 606, an elliptical rotating shaft 607, a tension spring 608, a buffer pad 609, a fixing block 610, a semi-circular screw rod 611, a connecting arm 612, a fixing shaft 613, and a rotating shaft 614;

[0062] The mounting bracket 604 is fixed to the support frame 402; for example, the mounting bracket 604 and the support frame 402 are fixed together by three bolts; each side of the mounting bracket 604 is rotatably connected to the top of a connecting arm 612; several fixed shafts 613 are fixed between two connecting arms 612; one end of the spring 601 is fixed to the top of the mounting bracket 604, and the other end of the spring 601 is hung on the outer periphery of one of the fixed shafts 613; the spring 601 is hung on the outer periphery of the fixed shafts 613 at different positions to adjust the tension of the spring 601; the spring 601 provides the upward rotational force for the connecting arm 612 relative to the mounting bracket 604.

[0063] The bottoms of the two connecting arms 612 clamp and fix the connecting block 603; the bottom of the connecting block 603 fixes the outer shell 605; the grippers 606 are rotatably and symmetrically mounted on both sides of the outer shell 605 via a pivot 614; the two grippers 606 are connected by a tension spring 608, and the connection point between the tension spring 608 and each gripper 606 is located above the pivot 614; the tension spring 608 causes the tops of the two grippers 606 to tend to move closer together and the bottoms to tend to move further apart.

[0064] An elliptical rotating shaft 607 is disposed between the two grippers 606; the threaded rod of the handle 602 passes through the connecting block 603 and then through the center of the elliptical rotating shaft 607, and is fixed to the fixing block 610 located below the elliptical rotating shaft 607; the fixing block 610 is used to keep the elliptical rotating shaft 607 rotating smoothly and to achieve a counterweight effect; the elliptical rotating shaft 607 and the handle 602 are connected and fixed; when the handle 602 rotates, it drives the elliptical rotating shaft 607 to rotate synchronously; the handle 602 and the connecting block 603 are connected by threads, which is used to allow the handle 602 to rotate to different positions relative to the connecting block 603, and to position it through the threads.

[0065] A horizontally oriented semi-circular screw rod 611 is fixed to the inner side of each of the grippers 606 facing each other; a buffer pad 609 is provided on the inner bottom side of each of the grippers 606 facing each other;

[0066] When the handle 602 drives the elliptical shaft 607 to rotate to the minimum lateral position along the clamping direction of the two clamping jaws 606, for example, when the handle 602 is rotated until it is parallel to the rail, under the tension of the tension spring 608, the top of the two clamping jaws 606 on both sides approaches and tightens, and the bottom extends outward away. The end faces of the two semi-circular screw rods 611 on both sides abut against the two sides of the elliptical shaft 607, which is the loosened state.

[0067] When the handle 602 drives the elliptical shaft 607 to rotate to its maximum lateral position along the clamping direction, during the rotation of the elliptical shaft 607, the two sides of the elliptical shaft 607 push the semi-circular screw rod 611 outward, thereby causing the jaws 606 on both sides to overcome the tension of the tension spring 608 and rotate around the shaft 614 connected to the housing 605. This causes the tops of the jaws 606 on both sides to move away from each other and the bottoms to move closer together. When the elliptical shaft 607 rotates to its maximum lateral position, for example, by rotating the handle 602 until it is perpendicular to the rail, i.e. Figure 4 As shown, the tension spring 608 is stretched to its maximum length, and the bottom of the grippers 606 on both sides clamps the two sides of the rail. This is the locked state, which locks the scanning device onto the rail.

[0068] As an example, the structure of robotic arm 9 is as follows:

[0069] The trolley has two tracks and two cable chains installed inside. Two robotic arms 9 are mounted on the trolley via the guide rails and cable chains. Once the desired scanning method is selected, the robotic arms 9, equipped with end probes, can repeatedly scan and detect the rail welds. Each robotic arm is equipped with three types of probes at its end, which are completely symmetrical and responsible for detecting damage to the rail head, rail jaw, rail web, and rail base.

[0070] The single-sided robotic arm 9 consists of 6 joints and 5 servo motors, with ultrasonic probes for weld seam detection installed at its end, including a 70° probe 12, a 0° probe 13, and a 45° probe 14. The core of this invention lies in integrating at least eight scanning methods for different areas and defect orientations of rail welds by controlling the coordinated motion mode of the two robotic arms and the working mode of the probes, thus forming a complete flaw detection process library.

[0071] See Figures 7-8Let the longitudinal direction of the rail be X-axis, the width direction of the rail be Y-axis, and the vertical direction be Z-axis; each of the robotic arms 9 includes a slider 901, a base 902, a first connecting arm 903, a second connecting arm 904, a third connecting arm 905, and 5 servo motors; the servo motors are connected to the flaw detector 3 via wiring harnesses;

[0072] The slider 901 is fixed to one end of the base 902. The slider 901 is slidably mounted to one side of the guide rail 7. For example, the slider 901 is stuck in the guide rail groove of the guide rail 7. The slider 901 is also fixed to a cable chain. Driven by the first servo motor, the cable chain moves, thereby driving the slider 901 to slide along the guide rail 7 in the X direction. Therefore, the slider 901 slides along the guide rail 7 in the X direction under the drive of the cable chain.

[0073] The other end of the base 902 is connected to one end of the first connecting arm 903 via a second servo motor; the rotation axis of the second servo motor is in the X direction, which is used to drive the first connecting arm 903 to rotate around its X axis, thereby adjusting the Y and Z positions.

[0074] The other end of the first connecting arm 903 is connected to one end of the second connecting arm 904 via a third servo motor; the rotation axis of the third servo motor is in the X direction, which is used to drive the second connecting arm 904 to rotate around its X axis, thereby adjusting the Y and Z positions;

[0075] The other end of the second connecting arm 904 is connected to the side of the third connecting arm 905 via a fourth servo motor; the rotation axis of the fourth servo motor is in the X direction, which is used to drive the third connecting arm 905 to rotate 360 ​​degrees around its X axis.

[0076] One end of the third connecting arm 905 is fixed with the 0° probe 13 and the 45° probe 14 in sequence; the other end of the third connecting arm 905 is provided with a fifth servo motor; the rotation axis of the fifth servo motor is Z-axis, and the output end of the fifth servo motor is equipped with the 70° probe 12, which is used to drive the 70° probe 12 to rotate 360 ​​degrees around its Z-axis.

[0077] In this invention, the control method for each servo motor is as follows: First, the target position of the probe is confirmed; then, based on the target position, inverse motion is solved to obtain the angle values ​​of the second, third, and fourth servo motors corresponding to the yz coordinates; and then the second, third, and fourth servo motors are controlled. Figure 7 In the diagram, A represents the second servo motor; B represents the third servo motor; C represents the fourth servo motor; and D represents the fifth servo motor.

[0078] Therefore, two robotic arms 9 are installed on the left and right sides of the middle of the handcart 1. Three probes are installed at the end of the robotic arms 9, namely a 70° probe 12, a 0° probe 13, and a 45° probe 14. The two robotic arms 9 are completely symmetrical. During operation, the robotic arms 9 reciprocate to repeatedly scan and detect the weld area.

[0079] This invention also provides a method for an intelligent rail weld inspection device based on dual robotic arm collaboration, comprising the following steps:

[0080] Step S1: Adjust the locking mechanism 6 to the loose state by using the handle 602. Under the elastic force of the spring 601, the connecting arm 612 rotates upward around the hinge point with the mounting bracket 604, thereby causing the outer shell 605 and all the components assembled to the outer shell 605 to rotate upward and away from the rail.

[0081] Step S2: Push the handcart 4 to move the land rail wheel 11 along the rail to the weld area to be probed;

[0082] Step S3: Start the first alignment device 2 and the second alignment device 8 to complete the alignment check operation;

[0083] Step S4: Press the outer shell 605 downward with external force to make the connecting arm 612 rotate downward around the hinge point with the mounting bracket 604, so that the outer shell 605 is in a vertical state; then operate the handle 602 to adjust the locking mechanism 6 to the locked state.

[0084] Step S5: The two robotic arms 9 are controlled in a coordinated manner to make them reciprocate and repeatedly scan and detect the weld area.

[0085] The detected weld quality data is transmitted in real time to the flaw detector 3 through the acquisition box 1. After being analyzed and processed by the flaw detector 3, it is displayed in the form of waveforms.

[0086] Step S6: After completing the scanning of the current weld seam area, return to step S1, adjust the locking mechanism 6 to the loose state using handle 602, and push the trolley 4 to the next weld seam area for scanning.

[0087] The specific steps of S5 above are as follows:

[0088] By controlling the coordinated motion mode of the dual robotic arms and the working mode of the probes, at least eight scanning methods are integrated to target different areas and defect orientations of rail welds. Specific scanning methods include:

[0089] ① Rail Bottom 70° Probe Scanning Method: Control the two robotic arms 9 to move synchronously, so that the 70° probes 12 at their ends are in single-fire and single-receive mode, and symmetrically scan the rail bottom area from both sides of the rail bottom slope to detect defects such as transverse cracks at the rail bottom;

[0090] ② Rail head 70° probe scanning method: Control the movement of the left robotic arm 9 so that the 70° probe 12 at its end can scan the rail head area from the top surface of the rail head tread to detect defects inside the rail head;

[0091] ③ 0° probe scanning method: Control the movement of the left robotic arm 9 so that the 0° probe 13 at its end is placed from the rail head tread. The 0° probe 13 adopts a 0° dual crystal probe, one transmitting and one receiving, and uses its sound beam characteristics to perform vertical or small-angle scanning of the longitudinal area from the rail head, rail web to the rail bottom, and detect defects that are roughly parallel to the tread.

[0092] ④ 45° probe scanning method: Control the movement of the left robotic arm 9 so that the single 45° probe 14 at its end emits ultrasonic waves from the rail head tread at a fixed refraction angle to scan the area extending from the rail web to the rail bottom and detect defects with a certain tilt angle.

[0093] ⑤ Rail head tandem K-type scanning method: The left robotic arm 9 is controlled as the transmitting unit and the right robotic arm 9 is controlled as the receiving unit. The 45° probes 14 at the ends of the two robotic arms 9 are placed opposite each other from the two sides of the rail head to form a K-type sound path. By synchronously moving the two robotic arms, the rail head is scanned in a penetrating manner, which is particularly suitable for detecting vertical or tilting defects inside the rail head.

[0094] ⑥ Rail Bottom Serial K-Type Scanning Method: The left robotic arm 9 is controlled as the transmitting unit and the right robotic arm 9 is controlled as the receiving unit. The 45° probes 14 at the ends of the two robotic arms 9 move to both sides of the rail bottom to perform K-type scanning on the rail bottom area to detect internal defects in the rail bottom area.

[0095] ⑦ Rail web front tandem scanning method: Control the left and right robotic arms 9 as transmitting and receiving units respectively, place the 45° probes 14 on the rail head tread surface, and position them on the same side, in front or to the left of the weld centerline. The two probes are arranged in tandem, one in front and one behind, and move along the longitudinal direction of the rail. The main purpose is to detect vertical defects in the front half of the weld, that is, the area near the scanning start side and the rail web area.

[0096] ⑧ Rail web tandem scanning method: Control the left and right robotic arms 9 as transmitting and receiving units respectively, place the 45° probes 14 on the rail head tread surface, and position them on the same side, behind or to the right of the weld centerline. The two probes are arranged in tandem, one in front of the other, and move along the longitudinal direction of the rail to detect vertical defects in the front half of the weld, that is, the area near the starting side of the scan and the rail web area.

[0097] This invention provides a method for an intelligent rail weld inspection device based on dual robotic arm collaboration. The main idea is as follows: After the centering device completes centering, the locking mechanism fixes the vehicle body to the rail. The robotic arm drives the ultrasonic probe to detect the entire weld area, and the data acquisition box collects the detection data and displays it on the flaw detector screen. After the inspection of the weld is completed, the flaw detector operator releases the locking mechanism and pushes the inspection device to the next weld.

[0098] Therefore, this invention provides an intelligent rail weld inspection device and method based on dual robotic arm collaboration. The inspection operator places the inspection device on the rail, opens the alignment device to center the device on the rail, and uses a locking device to lock the instrument onto the rail. Finally, the power supply to the data acquisition box and the flaw detector is turned on, and the desired inspection method is selected on the flaw detector interface. The robotic arm automatically performs weld inspection. Through the combined application of eight inspection methods, systematic detection of defects across the entire cross-section of rail welds, including the rail head, rail web, and rail bottom, as well as defects of different orientations (horizontal, vertical, and inclined), is achieved. This solves the technical problems of low accuracy and low efficiency in manual flaw detection in existing technologies.

[0099] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An intelligent rail weld inspection device based on dual robotic arm collaboration, characterized in that, The system includes a handcart (4), which includes a support platform (401). The support platform (401) has symmetrically fixed vertical support frames (402) at its front and rear ends. Each support frame (402) has a land rail wheel (11) at its bottom center. At least one support frame (402) has a locking mechanism (6) at its bottom. The top of the support platform (401) is equipped with a data acquisition box (1) and a flaw detector (3); the bottom of the support platform (401) is fixed with a guide rail (7) along the longitudinal direction of the rail; on the left and right sides of the guide rail (7), there are symmetrically arranged robotic arms (9) that can slide along the guide rail (7); each robotic arm (9) has a 70° probe (12), a 0° probe (13) and a 45° probe (14) integrated at its end; each robotic arm (9) is equipped with an independent drive mechanism; the rail data detected by each probe is transmitted to the data acquisition box (1); the data acquisition box (1) is connected to the flaw detector (3) and is displayed through the flaw detector (3).

2. The intelligent rail weld inspection device based on dual robotic arm collaboration according to claim 1, characterized in that, Two first centering devices (2) are installed on the top of the support platform (401); a second centering device (8) is installed in the middle of the bottom surface of the guide rail (7). The two first centering devices (2) emit two laser beams. When the two laser beams are close to and parallel to the two sides of the rail being tested, and at the same time the cross-shaped laser beam emitted by the second centering device (8) is at the center of the rail being tested, it indicates that the intelligent rail weld inspection device based on the collaboration of two robotic arms has completed centering.

3. The intelligent rail weld inspection device based on dual robotic arm collaboration according to claim 1, characterized in that, A lifting handle (10) is installed on the top surface and on the left and right sides of the support platform (401); a push handle (5) is provided on the rear side of the support platform (401).

4. The intelligent rail weld inspection device based on dual robotic arm collaboration according to claim 1, characterized in that, The locking mechanism (6) includes a spring (601), a handle (602), a connecting block (603), a mounting bracket (604), a housing (605), a gripper (606), an elliptical rotating shaft (607), a tension spring (608), a buffer pad (609), a fixing block (610), a semi-circular screw rod (611), a connecting arm (612), a fixing shaft (613), and a rotating shaft (614). The mounting bracket (604) is fixed to the support frame (402); each side of the mounting bracket (604) is rotatably connected to the top of a connecting arm (612); a plurality of fixed shafts (613) are fixed between the two connecting arms (612); one end of the spring (601) is fixed to the top of the mounting bracket (604), and the other end of the spring (601) is hung on the outer periphery of a fixed shaft (613); the spring (601) provides the connecting arm (612) with the rotational force to rotate upward relative to the mounting bracket (604); The bottom of the two connecting arms (612) clamps and fixes the connecting block (603); the bottom of the connecting block (603) fixes the outer shell (605); the two sides of the outer shell (605) are rotatably and symmetrically mounted with the grippers (606) through the pivot (614); the two grippers (606) are connected by the tension spring (608), and the connection point of the tension spring (608) with each gripper (606) is located above the pivot (614); through the tension spring (608), the tops of the two grippers (606) tend to move closer together, and the bottoms tend to move further apart; An elliptical shaft (607) is disposed between the two grippers (606); the threaded rod of the handle (602) passes through the connecting block (603) and then through the center of the elliptical shaft (607), and is fixed to the fixing block (610) located below the elliptical shaft (607); when the handle (602) rotates, it drives the elliptical shaft (607) to rotate synchronously; A horizontally oriented semi-circular screw rod (611) is fixed to the inner side of each of the grippers (606); a buffer pad (609) is provided on the inner bottom side of each of the grippers (606). When the handle (602) drives the elliptical shaft (607) to rotate to the minimum lateral position along the clamping direction of the two clamping claws (606), under the tension of the tension spring (608), the tops of the two clamping claws (606) move closer together and the bottoms move further apart, and the end faces of the two semi-circular screw rods (611) abut against the two sides of the elliptical shaft (607), which is the loosened state; When the handle (602) drives the elliptical shaft (607) to rotate to the maximum lateral position along the clamping direction, during the rotation of the elliptical shaft (607), the two sides of the elliptical shaft (607) push the semi-circular screw rod (611) outward, thereby causing the jaws (606) on both sides to overcome the tension of the tension spring (608) and rotate around the shaft (614) connected to the outer shell (605), thereby causing the tops of the jaws (606) on both sides to move away and the bottoms to move closer. When the elliptical shaft (607) rotates to the maximum lateral position, the bottoms of the jaws (606) on both sides clamp the two sides of the rail, which is the locked state.

5. The intelligent rail weld inspection device based on dual robotic arm collaboration according to claim 1, characterized in that, Let the longitudinal direction of the rail be X, the width direction of the rail be Y, and the vertical direction be Z; each of the robotic arms (9) includes a slider (901), a base (902), a first connecting arm (903), a second connecting arm (904), a third connecting arm (905), and 5 servo motors; One end of the base (902) is fixed to the slider (901), and the slider (901) is slidably mounted on one side of the guide rail (7). Under the drive of the first servo motor, it slides along the guide rail (7) in the X direction. The other end of the base (902) is connected to one end of the first connecting arm (903) through the second servo motor. The rotation axis of the second servo motor is in the X direction, which is used to drive the first connecting arm (903) to rotate around its X axis, thereby adjusting the Y and Z positions. The other end of the first connecting arm (903) is connected to one end of the second connecting arm (904) via a third servo motor; the rotation axis of the third servo motor is in the X direction, which is used to drive the second connecting arm (904) to rotate around its X axis, thereby adjusting the Y and Z positions; The other end of the second connecting arm (904) is connected to the side of the third connecting arm (905) via a fourth servo motor; the rotation axis of the fourth servo motor is in the X direction, which is used to drive the third connecting arm (905) to rotate 360 ​​degrees around its X axis; One end of the third connecting arm (905) is fixed with the 0° probe (13) and the 45° probe (14) in sequence; the other end of the third connecting arm (905) is provided with a fifth servo motor; the rotation axis of the fifth servo motor is Z-axis, and the output end of the fifth servo motor is equipped with the 70° probe (12) for driving the 70° probe (12) to rotate 360 ​​degrees around its Z-axis.

6. A method for an intelligent rail weld inspection device based on dual robotic arm collaboration as described in any one of claims 1-5, characterized in that, Includes the following steps: Step S1: Adjust the locking mechanism (6) to the loose state by using the handle (602). Under the elastic force of the spring (601), the connecting arm (612) rotates upward around the hinge point with the mounting bracket (604), thereby causing the outer shell (605) and all the parts assembled to the outer shell (605) to rotate upward and move away from the rail. Step S2, push the handcart (4) to move the rail wheel (11) along the rail to the weld area to be probed; Step S3: Start the first alignment device (2) and the second alignment device (8) to complete the alignment check operation; Step S4: Press the outer shell (605) down with external force to make the connecting arm (612) rotate downward around the hinge point with the mounting bracket (604) and make the outer shell (605) vertical; then operate the handle (602) to adjust the locking mechanism (6) to the locking state. Step S5: Coordinate the control of the two robotic arms (9) to make them reciprocate and repeatedly scan and detect the weld area. The detected weld quality data is transmitted in real time to the flaw detector (3) through the acquisition box (1). After being analyzed and processed by the flaw detector (3), it is displayed in the form of waveform. Step S6: After completing the current weld area scan, return to step S1, use handle (602) to adjust the locking mechanism (6) to the loose state, and push the trolley (4) to the next weld area for scanning.

7. The method of an intelligent rail weld inspection device based on dual robotic arm collaboration according to claim 6, characterized in that, Step S5 is as follows: By controlling the coordinated motion mode of the dual robotic arms and the working mode of the probes, at least eight scanning methods are integrated to target different areas and defect orientations of rail welds. Specific scanning methods include: ① Rail Bottom 70° Probe Scanning Method: Control the two robotic arms (9) to move synchronously, so that the 70° probes (12) at their ends are in single-fire and single-receive mode, and symmetrically scan the rail bottom area from the two inclined surfaces of the bottom of the rail to detect transverse crack defects at the rail bottom; ② Rail head 70° probe scanning method: Control the movement of the left robotic arm (9) so that the 70° probe (12) at its end can scan the rail head area from the top surface of the rail head tread to detect defects inside the rail head; ③ 0° probe scanning method: control the movement of the left robotic arm (9) so that the 0° probe (13) at its end is placed from the rail head tread. The 0° probe (13) adopts a 0° dual crystal probe, one transmitting and one receiving, and uses its sound beam characteristics to perform vertical or small angle scanning of the longitudinal area from the rail head, rail web to the rail bottom, and detect defects that are roughly parallel to the tread. ④ 45° probe scanning method: Control the movement of the left robotic arm (9) so that the single 45° probe (14) at its end emits ultrasonic waves from the rail head tread at a fixed refraction angle to scan the area extending from the rail web to the rail bottom and detect defects with a certain tilt angle. ⑤ Rail head tandem K-type scanning method: control the left robotic arm (9) as the transmitting unit and the right robotic arm (9) as the receiving unit. The 45° probes (14) at the ends of the two robotic arms (9) are placed opposite each other from the two sides of the rail head to form a K-type sound path. By synchronously moving the two robotic arms, the rail head is scanned in a penetrating manner, which is suitable for detecting vertical or tilting defects inside the rail head. ⑥ Track bottom tandem K-type scanning method: Control the left robotic arm (9) as the transmitting unit and the right robotic arm (9) as the receiving unit. The 45° probes (14) at the ends of the two robotic arms (9) move to the two sides of the track bottom to perform K-type scanning on the track bottom position to detect internal defects in the track bottom area. ⑦ Rail web front tandem scanning method: Control the left and right robotic arms (9) as transmitting and receiving units respectively, place the 45° probes (14) on the rail head tread and on the same side of the weld center line, in front or on the left, arrange the two probes in a tandem arrangement, one in front and one behind, and move along the longitudinal direction of the rail to detect vertical defects in the front half of the weld, that is, the area close to the scanning start side and the rail web area; ⑧ Rail web tandem scanning method: Control the left and right robotic arms (9) as transmitting and receiving units respectively, place the 45° probes (14) on the rail head tread and on the same side of the weld center line, behind or to the right. The two probes are arranged in tandem, one in front and one behind, and move along the longitudinal direction of the rail to detect vertical defects in the front half of the weld, that is, the area close to the scanning start side and the rail web area.

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