Steel rail welding seam flaw detection robot and flaw detection method thereof

Abstract

The invention discloses a steel rail welding seam flaw detection robot and a flaw detection method thereof, and relates to the technical field of steel rail welding seam flaw detection. The robot comprises a walking platform erected on the steel rail, an electric sliding table arranged at the front end of the walking platform, a mechanical arm arranged on the sliding table in a sliding mode, a scanning frame arranged at the free end of the mechanical arm, a probe arranged on the scanning frame and a controller for controlling the electric sliding table and the mechanical arm. The flaw detection method comprises the following steps: walking on a platform upper rail, positioning a welding seam, cleaning the welding seam, spraying a coupling agent, and controlling a mechanical arm and an electric sliding table by a controller to drive a probe to carry out scanning flaw detection on the welding seam. The robot can replace manual steel rail welding seam flaw detection operation in the prior art to a great extent, the technical problem that time and labor are wasted in manual operation is effectively solved, the flaw detection method can cover the whole longitudinal sections of the two ends and the middle of the welding seam, and the damage condition of the steel rail welding seam can be completely and accurately reflected.

Description

Technical Field

[0001] This invention relates to the field of rail weld flaw detection technology, and in particular to a rail weld flaw detection robot and its flaw detection method. Background Technology

[0002] To ensure the efficient and safe operation of high-speed trains, real-time and periodic inspection of rail damage is crucial. Given the sheer volume of work, manual labor alone is clearly insufficient. Current weld inspection procedures require operators to carry equipment and handheld probes to meticulously scan the welds according to established processes. This process involves not only equipment handling but also multiple steps such as rust removal and cleaning, resulting in low efficiency. Furthermore, this labor-intensive work model places immense strain on the workers' bodies, highlighting the high workload and necessitating immediate improvement. Summary of the Invention

[0003] In view of the technical problems existing in the prior art, the embodiments of this application provide a rail weld flaw detection robot and its flaw detection method, which solves many problems of the shortcomings of manual operation in the prior art, achieves the effect of saving time and labor, and the flaw detection method can completely and accurately reflect the damage of rail welds.

[0004] To achieve the above objectives, the rail weld flaw detection robot disclosed in this application includes:

[0005] The traveling platform is erected on the aforementioned steel rails;

[0006] An electric slide table is laterally positioned at the front end of the traveling platform;

[0007] A six-axis collaborative robotic arm, wherein the robotic arm is slidably mounted on a slide table;

[0008] An ultrasonic phased array probe, located at one end of the robotic arm, is used to scan the rail welds.

[0009] The controller, in conjunction with the provided motor driver, enables the movement of the robotic arm and the electric slide.

[0010] Furthermore, the traveling platform includes a chassis and a pair of front wheels and a pair of rear wheels located at the front and rear ends of the chassis, and the traveling platform uses a hub motor as the drive motor; a center console is provided at the front end of the chassis, and a control panel is provided on the center console for controlling the movement and parking of the traveling platform.

[0011] Furthermore, the robots also include:

[0012] A scanning bracket is connected to one end of a robotic arm. The probe is mounted on the scanning bracket, and the scanning bracket changes the scanning position of the probe under the drive of the robotic arm.

[0013] Furthermore, the scanning bracket includes:

[0014] A vertical support is connected to one end of a robotic arm at its top, and a first probe is connected to the bottom of the vertical support. The first probe is used to scan the longitudinal sections on both sides of the weld at the rail bottom and rail head.

[0015] A connecting bracket, one end of which is vertically connected to one side of the top of the vertical bracket, and the other end of which is vertically connected to the middle of the longitudinal bracket;

[0016] The longitudinal support is equipped with a second probe, which is used to scan for damage to the longitudinal section of the weld between the rail head and the rail base, as well as at the rail web.

[0017] Furthermore, the robots also include:

[0018] The force control sensor is located between one end of the robotic arm and the top of the vertical support.

[0019] Furthermore, the vertical support includes:

[0020] A cylindrical component, wherein a spring is provided in its cavity, and a limiting post is provided on the inner wall of the cavity of the cylindrical component.

[0021] The telescopic component is movably inserted into the lower end of the cylindrical component, the top end of the telescopic component abuts against the lower end of the spring, and a limiting groove is provided on the side wall of the telescopic component, and the limiting post is inserted into the limiting groove.

[0022] A floating joint is located at the bottom of the telescopic component, and the bottom end of the floating joint is connected to the first probe.

[0023] Furthermore, the longitudinal support includes:

[0024] A rectangular plate with a perforated structure in the middle;

[0025] A pair of pulleys are respectively mounted on longitudinal supports at both ends of the slot, the pulleys are rotatably connected to the ends of the longitudinal supports, and a toothed belt is connected between the two pulleys;

[0026] The second probe includes a transmitter and a receiver. Both the transmitter and the receiver have slots on their bottom sides. The transmitter and the receiver are slidably engaged with the slots on the sides of the longitudinal support's perforated structure. A first through hole is provided on one side of the transmitter, and a second through hole is provided on the outside of the receiver opposite to the first through hole. The toothed belt passes through the first through hole on one side and the second through hole on the other side. The transmitter side in the first through hole and the receiver side in the second through hole are respectively provided with teeth that mesh with and drive the toothed belt. The drive pulley can realize the relative or opposite movement of the transmitter and the receiver.

[0027] Based on the aforementioned robot, the rail weld flaw detection method disclosed in this application includes the following steps:

[0028] The platform moves along the rail, and the rail welds on one side are first scanned and inspected. After the rail welds on one side are scanned, the probe is moved and adjusted to scan the rail welds on the other side.

[0029] For weld seam positioning, the traveling platform stops when the probe moves to a position near the weld seam. The weld seam positioning method uses a sliding table for positioning. When the sliding table moves with the traveling platform to the weld seam position, the end of the sliding table is exactly aligned with the weld seam, at which point the traveling platform stops.

[0030] The controller manipulates the robotic arm and electric slide to drive the probe to perform a comprehensive scan and flaw detection of the weld.

[0031] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages:

[0032] By adopting a self-propelled traveling platform, a slide table located at the front end of the traveling platform and driving the lateral displacement of the robotic arm, a six-axis collaborative robotic arm, and a probe mounted on the robotic arm, the probe can be adjusted in multiple dimensions. This can largely replace the manual rail weld flaw detection work in the existing technology, effectively solving the technical problems of time-consuming and labor-intensive manual operations and reducing the intensity of manual labor in the flaw detection process.

[0033] The scanning and flaw detection process used in this application includes the following: the first probe moves upward and downward along the inner rail bottom, upward and downward along the outer rail bottom, large-angle scanning, upward and downward along the rail surface, and the second probe scans the left, middle and right longitudinal sections of the weld. This scanning can cover the entire longitudinal section of the weld at both ends and the middle three positions, and can completely and accurately reflect the damage condition of the rail weld. Attached Figure Description

[0034] 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 the structures shown in these drawings without creative effort.

[0035] Figure 1 This is a three-dimensional structural diagram (right side view) of the rail weld flaw detection robot provided in the embodiments of this application;

[0036] Figure 2 This is a three-dimensional structural diagram (left side view) of the rail weld flaw detection robot provided in the embodiments of this application;

[0037] Figure 3 This is a three-dimensional structural diagram of the scanning bracket in the embodiments of this application;

[0038] Figure 4 This is a schematic diagram of the scanning bracket in an embodiment of this application;

[0039] Figure 5 This is a schematic diagram of the longitudinal support structure in an embodiment of this application;

[0040] Figure 6 This is a diagram showing the usage status of the first probe when scanning the weld seam at the bottom of the rail in the embodiments of this application;

[0041] Figure 7 This is a schematic diagram of the first probe scanning the weld path on the rail in an embodiment of this application;

[0042] Figure 8 This is a schematic diagram of the longitudinal section of the rail bottom weld scanned by the first probe in an embodiment of this application;

[0043] Figure 9 This is a schematic diagram of the longitudinal section of the rail head weld scanned by the first probe in an embodiment of this application;

[0044] Figure 10 This is a diagram showing the usage status of the longitudinal support when scanning the weld at the rail head in this application embodiment (the second probe is not shown);

[0045] Figure 11 This is a schematic diagram of the second probe scanning the longitudinal section of the rail weld in an embodiment of this application;

[0046] Explanation of icon numbers:

[0047] 1-Running platform; 101-Chassis; 102-Center console; 103-Control panel; 104-Seat; 105-Front wheel; 106-Rear wheel; 107-Wheel rim;

[0048] 2-sliding platform;

[0049] 3-Robotic arm;

[0050] 4-Scanning bracket; 401-Vertical bracket; 402-Connecting bracket; 403-Longitudinal bracket; 404-First probe; 405-Columnar component; 406-Telescopic component; 407-Floating joint; 408-Spring; 409-Limiting post; 410-Limiting groove; 411-Rectangular plate; 412-Pulley; 413-Toothed belt; 414-Transmitter; 415-Receiver; 416-Strip hole;

[0051] 5-Rail; 501-Rail base; 502-Rail web; 503-Rail head; 504-Weld;

[0052] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0053] This application provides a method and robot for inspecting rail welds, which replaces the manual rail weld inspection work in the prior art, achieving the effect of saving time and labor.

[0054] The technical solution in this application aims to address the problems of low efficiency and labor-intensive manual rail weld inspection operations. The overall approach is as follows:

[0055] First, this application proposes a rail weld flaw detection robot. This device achieves the above-mentioned objective by setting up a traveling platform on the rail, installing a slide table on the traveling platform, setting a robotic arm on the slide table, and attaching a probe at one end of the robotic arm. The traveling platform can move along the rail diameter direction on the rail, the slide table is used for the robotic arm to move laterally between the two rails, the robotic arm is used for the spatial movement of the probe so that the probe can scan the weld position of the rail, and the probe is electrically connected to a display, through which the operator can observe the weld flaw detection results.

[0056] Secondly, this application also proposes a method for inspecting rail welds, which includes:

[0057] The process includes steps such as platform rail movement, weld seam positioning, weld seam cleaning and coupling agent spraying, and flexible robotic arm clamping ultrasonic phased array probes for scanning.

[0058] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0059] like Figures 1-2 As shown, a rail weld flaw detection robot includes a traveling platform 1, a slide 2 disposed at the front end of the traveling platform 1, a robotic arm 3 slidably disposed on the slide 2, and a probe disposed at the end of the robotic arm 3. The traveling platform, as the basic carrier platform of the rail weld flaw detection robot, provides the robot with basic structural support, travel control, power supply, and other functions, replacing manual walking. Figure 2As shown, the traveling platform 1 specifically includes a chassis 101, a center console 102 located at the front of the chassis 101, a control panel 103 on the center console 102 for controlling the movement and parking of the traveling platform 1, a seat 104 located in the middle of the chassis 101, and a pair of front wheels 105 and a pair of rear wheels 106 located at the front and rear ends of the chassis 101. When in use, the front wheels 105 and rear wheels 106 are mounted on the steel rails on both sides, enabling the traveling platform 1 to move on the steel rails 5. Regarding the power of the traveling platform, this embodiment preferably uses four hub motors as drive motors. Hub motors are designed to integrate the power system, transmission system, and braking system of the equipment. Eliminating the transmission system significantly reduces the weight of the platform equipment compared to differential motors. Because hub motors have the characteristic of independent drive for each wheel, they can achieve various complex drive modes. Therefore, front-wheel drive, rear-wheel drive, and four-wheel drive can be easily implemented, making it more flexible, reliable, and practical. For example, during normal operation, the platform defaults to front-drive. If the current drive system malfunctions, it can switch to the backup power system, i.e., rear-drive, to ensure that the terminal equipment can complete its work smoothly or safely evacuate within designated work windows. It also supports four-wheel drive to enhance its climbing ability. In some examples, the power supply uses an onboard lithium battery to power the various motors and electrical components in this embodiment, specifically by configuring multiple lithium battery packs (48V / 60Ah). Preferably, the platform has a range of at least 40km or 3 hours, and its travel speed is 0-20km / h.

[0060] In this embodiment of the application, in order to prevent the platform from derailing while traveling on the rails, a flange 107 structure is provided on the inner side of both the front wheel and the rear wheel, and the diameter of the flange is larger than the diameter of the front wheel and the rear wheel (the diameters of the front wheel and the rear wheel are the same).

[0061] In this embodiment, the slide table 2 is horizontally positioned below the front end of the traveling platform 1, with both ends of the slide table 2 located above the two side rails. The slide table 2 is equipped with a sliding block that can move along its length. The fixed end of the robotic arm 3 is connected to the sliding block. The movement of the sliding block drives the robotic arm to move laterally between the two side rails, changing the lateral position of the probe between the two side rails, thus flexibly scanning, inspecting, and adjusting the two side rails. In one embodiment of this application, the slide table 2 is an electric slide table. The electric slide table uses a first motor to drive the sliding block and the robotic arm to move laterally. Preferably, the transmission method of the electric slide table is a screw drive.

[0062] The robotic arm 3 used in this embodiment is a six-axis collaborative robotic arm, which is based on a six-degree-of-freedom structure and a high-precision motion control system. This type of robotic arm typically consists of six joints connected together, each joint capable of rotational movement along an axis, thus realizing the robot's six degrees of freedom. The six-axis collaborative robotic arm can achieve the robot's collaborative operation capabilities through six-axis collaborative control. In six-axis collaborative control, the joints possess a certain degree of flexibility, enabling more flexible and efficient collaborative control.

[0063] In some instances, a six-axis force control sensor is connected to one end of the robotic arm 3 via a flange. This force control sensor is a strain gauge torque sensor, specifically a VI-type force sensor, model JK-SE-VI-200. The force control sensor is directly connected to the TIO interface at the end of the robotic arm. The force control sensor collects the force acting on the rail during the scanning process and feeds it back to the robot's control system. The control system then controls the contact force exerted by the probe on the bottom or surface of the rail to remain constant during the scanning process, thereby improving the scanning effect.

[0064] In this embodiment, a phased array probe is used to scan the rail weld. It consists of multiple crystals arranged in a specific pattern. Software allows for individual control of the excitation time of each crystal, thereby controlling the shape and direction of the emitted ultrasonic beam (wavefront), achieving beam scanning, deflection, and focusing of the ultrasonic waves. This allows for the detection of defects in different orientations and locations, which may be randomly distributed away from the beam axis. In contrast, ordinary single-crystal probes, due to their limited range of motion and beam angle, are prone to missing defects that are directionally unfavorable or located far from the beam axis.

[0065] like Figure 3 As shown in this embodiment, the probe is connected to one end of the robotic arm 3 via a scanning bracket 4. The scanning bracket 4 includes a vertical bracket 401, a connecting bracket 402, and a longitudinal bracket 403. The top end of the vertical bracket 401 is connected to one end of the robotic arm 3, and the bottom end of the vertical bracket 401 is connected to a first probe 404. The first probe 404 is used to move and scan from a certain position on the rail bottom and rail surface towards the weld, scanning the damage to the longitudinal sections on both sides of the weld at the rail bottom and rail head. One end of the connecting bracket 402 is vertically connected to one side of the top of the vertical bracket 401, and the other end of the connecting bracket 402 is vertically connected to the middle of the longitudinal bracket 403. A second probe is provided on the longitudinal bracket 403. The second probe is used for moving and scanning the rail surface, scanning the damage to the longitudinal sections of the weld between the rail head and rail bottom and at the rail web.

[0066] like Figure 4As shown in the embodiment of this application, the vertical support 401 includes a column cylinder 405, a telescopic member 406, and a floating joint 407. The top end of the column cylinder 405 is connected to a force control sensor via a flange. A spring 408 is built into the cylinder cavity of the column cylinder 405. The telescopic member 406 is movably inserted into the lower end of the column cylinder 405, and the top end of the telescopic member 406 abuts against the spring 408. Pressing the telescopic member 406 causes the spring 408 to retract. A limiting post 409 is provided on the inner wall of the cylinder cavity of the column cylinder 405, and a limiting groove 410 is provided on the side wall of the telescopic member 406. The limiting post 409 is inserted into the limiting groove 410 to achieve a limiting connection between the telescopic member 406 and the column cylinder 405. The bottom of the telescopic component 406 is connected to a floating joint 407 for buffering. The bottom end of the floating joint 407 is connected to the first probe 404. The sound beam of the first probe 404 passes through a wedge and is obliquely incident on the rail at an angle of K2.5 (68.2°) for detection. The design of the vertical support structure above provides a downward pressure buffer space for the probe to contact the bottom of the rail for detection.

[0067] like Figure 5 As shown in one embodiment of this application, the longitudinal support 403 is a rectangular plate 411 with a central perforation 416. A pulley 412 is respectively provided on both ends of the longitudinal support 403 at the two ends of the perforation 416. The pulleys 412 are rotatably connected to the ends of the longitudinal support 403. A toothed belt 413 connects the two pulleys 412. The second probe includes a transmitter 414 that emits a detection signal to the flaw detection point, a reflected signal generated by the weld seam at the flaw detection point, and a receiver 415 for collecting the reflected signal and sending it to the processor. Slots are provided on both sides of the bottom of the transmitter 414 and the receiver 415. 415 is slidably engaged with both sides of the slot 416 structure of the longitudinal support 403 through the slot on the side, so that the transmitter 414 and the receiver 415 can slide in the slot 416. A first through hole is provided on one side of the transmitter 414, and a second through hole is provided on the outside of the receiver 415 on the opposite side of the first through hole. The toothed belt 413 passes through the first through hole on one side and the second through hole on the other side. The transmitter 414 in the first through hole and the receiver 415 in the second through hole are respectively provided with teeth that mesh with the toothed belt 413 for transmission. The drive pulley assembly can realize the synchronous relative or opposite movement of the transmitter and the receiver in the slot.

[0068] For example, in order to drive the pulley assembly, a knob can be set on either pulley 412 or a second motor can be connected and installed to drive it.

[0069] As an example, to reduce costs, power consumption, and improve performance, the motion control controller uses a TMS320F28335 digital signal processor in conjunction with a motor driver to realize the movement of the robotic arm and the various motors in the equipment.

[0070] It should be noted that the hub motor, six-axis collaborative robotic arm, phased array probe, force control sensor, electric slide, TMS320F28335 digital signal processor, and other devices described in the embodiments of this application are all existing technologies and can be directly purchased from the market. The specific structural details of the above devices will not be repeated. For those skilled in the art, the functions of the hub motor, six-axis collaborative robotic arm, phased array probe, force control sensor, electric slide, TMS320F28335 digital signal processor, and other devices in the embodiments of this application should be clear and complete.

[0071] Based on the aforementioned rail weld flaw detection robot, the rail weld flaw detection method proposed in this application specifically includes the following steps:

[0072] (1) When the platform moves along the rail, the rail weld on one side is first scanned and inspected. After scanning the rail weld on one side, the probe is moved and adjusted to scan the rail weld on the other side.

[0073] (2) Weld seam positioning: When the probe moves to a position near the weld seam, the traveling platform stops;

[0074] As an embodiment of this application, the weld positioning method uses a slide table for positioning. When the slide table moves to the weld position with the traveling platform, the end of the slide table is aligned with the weld. At this time, the traveling platform stops, and since the robotic arm is mounted on the slide table, the robotic arm and the weld are also aligned synchronously.

[0075] (3) The controller operates the robotic arm and electric slide to drive each probe to perform the following scanning and flaw detection process on the weld:

[0076] 3.1 Track Bottom Scan (First Probe)

[0077] like Figure 6 and Figure 7 As shown, taking weld 504 as the object, the rail bottom 501 is scanned in four longitudinal sections (i.e., the longitudinal section at the joint between the rail bottom and the weld). The scanning paths for the four longitudinal sections are inner rail bottom upward, inner rail bottom downward, outer rail bottom upward, and outer rail bottom downward, respectively. The scanning process for the four longitudinal sections is the same, as detailed below:

[0078] The rail base is divided into four sections, with distances of 15mm, 23mm, 38mm, and 53mm from the rail base respectively.

[0079] First, at the first gear, 15mm from the bottom of the rail, start from 50-150mm from the weld. First, use a serrated scan to scan towards the weld. After the scan, return to the starting position (the same applies below). Then, use an angled scan, moving towards the weld with an inward 5° skew. Then, move towards the weld with an outward 5° skew.

[0080] Next, at the second gear, 23mm from the rail base, starting from 50-150mm from the weld, first use a serrated scan, scanning towards the weld; then use an angled scan, moving towards the weld with an inward 5° skew; then move towards the weld with an outward 5° skew.

[0081] Then, at position 38mm from the rail base, starting from 50-150mm from the weld, first use a serrated scan, scanning towards the weld; then use an angled scan, moving towards the weld with an inward 8-10° skew; then move towards the weld with an outward 8-10° skew.

[0082] Next is the fourth gear, 53mm from the bottom of the rail. Starting from 50-150mm from the weld, first use a serrated scan to scan towards the weld; then use an angled scan, moving towards the weld with an inward 8-10° skew; then move towards the weld with an outward 8-10° skew.

[0083] Finally, starting from the middle position of the first and second gears, 150mm away from the weld, a large-angle scan is performed towards the weld reinforcement at the bottom of the opposite rail. The purpose of the large-angle scan is to confirm whether there is any damage at the weld of the bottom of the opposite rail. The purpose of the serrated scan of each gear combined with the angle scan is to confirm whether there is any damage to the entire longitudinal section at the joint between the rail bottom and the weld.

[0084] like Figure 8 As shown, gear 1, gear 2, gear 3, and gear 4 scan the longitudinal section regions ①, ②, ③, and ④ at the weld end, respectively. The shaded areas in the figure are the areas inspected by the off-angle scan. To ensure the integrity of the inspection, the areas scanned by each off-angle scan will overlap to some extent.

[0085] 3.2 Rail surface scanning (first probe + second probe)

[0086] First probe scan:

[0087] The first probe scan of the rail surface is divided into two longitudinal sections (i.e., the longitudinal section at the joint between the rail head and the weld). The scanning paths for the two longitudinal sections are upward and downward, respectively, and the scanning process for the two longitudinal sections is the same, as follows:

[0088] Starting from the center line of the rail surface (starting point), begin scanning 250mm from a distance of 250mm from the weld with a 0° skew angle towards the weld, and move 250mm. After scanning, return to the starting position (the same applies below); then scan 250mm from a 8° inward skew angle towards the weld; then scan 250mm from a 8° outward skew angle towards the weld.

[0089] Then, the scanner is shifted to both the inner and outer sides of the rail, but each shift must ensure a 15% overlap with the previous scan until the rail surface is completely covered. After each shift, the scanner is moved 250mm from 250mm away from the weld with a 0° skew angle towards the weld. Then, it is moved 250mm with an inward skew angle of 8° towards the weld, and then 250mm with an outward skew angle of 8° towards the weld.

[0090] like Figure 9 As shown, the shaded areas on both sides are the areas scanned at an angle, and the area between the two shaded areas is the area scanned at a 0° angle.

[0091] See Figure 10 As shown, the requirements for scanning with the second probe are as follows:

[0092] Since the second probe scans the longitudinal section of the weld between the rail head 503 and the rail bottom 501, as well as the rail web 502, the scanning area is large, so a dual probe system with a transmitter and a receiver is required.

[0093] like Figure 5 As shown, the transmitter and receiver are both located at the two ends of the slot, respectively. An alignment line is provided on the rectangular plate on the side of the transmitter facing the receiver. When the longitudinal support is used for scanning, its probe is located at the center line of the rail surface. The subsequent scanning process consists of the following three steps:

[0094] (1) First, align the alignment line with the left edge of the weld, drive the pulley assembly so that the transmitter and receiver at both ends move relative to each other until the transmitter passes the weld, and then drive the pulley assembly so that the transmitter and receiver return to the positions at both ends of the slot.

[0095] (2) Align the alignment line with the center line of the weld, drive the pulley assembly so that the transmitter and receiver at both ends move relative to each other until the transmitter passes the weld, and then drive the pulley assembly so that the transmitter and receiver return to the positions at both ends of the slot.

[0096] (3) Finally, align the alignment line with the right edge of the weld and drive the pulley assembly so that the transmitters and receivers at both ends move relative to each other until the transmitters pass over the weld.

[0097] See Figure 11As shown, the shaded area represents the region scanned by the second probe, including longitudinal section damage at both ends and the middle of the weld.

[0098] The scanning and flaw detection process described in this application embodiment can cover the entire longitudinal section of the weld at both ends and the middle three positions, and can completely and accurately reflect the damage condition of the rail weld.

[0099] It is worth noting that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0100] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0101] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. The meaning of "and / at" throughout the text is to include three parallel solutions; taking "A and / or B as an example," it includes solution A, or solution B, or a solution that simultaneously satisfies A and B. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0102] The above description is merely 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 foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A rail weld flaw detection robot, characterized in that, Includes the following structure: A traveling platform, which is erected on the steel rails; An electric slide table is laterally positioned at the front end of the traveling platform; A six-axis collaborative robotic arm, wherein the robotic arm is slidably mounted on a slide table; An ultrasonic phased array probe, located at one end of the robotic arm, is used to scan the rail welds. The controller, in conjunction with the provided motor driver, enables the movement of the robotic arm and the slide.

2. The rail weld flaw detection robot according to claim 1, characterized in that, The traveling platform includes a chassis and a pair of front wheels and a pair of rear wheels located at the front and rear ends of the chassis. The traveling platform uses a hub motor as the drive motor. A center console is located at the front end of the chassis, and a control panel on the center console is used to control the movement and parking of the traveling platform.

3. The rail weld flaw detection robot according to claim 1, characterized in that, Also includes: A scanning bracket is connected to one end of a robotic arm. The probe is mounted on the scanning bracket, and the scanning bracket changes the scanning position of the probe under the drive of the robotic arm.

4. The rail weld flaw detection robot according to claim 3, characterized in that, The scanning bracket includes: A vertical support is connected to one end of a robotic arm at its top, and a first probe is connected to the bottom of the vertical support. The first probe is used to scan the longitudinal sections on both sides of the weld at the rail bottom and rail head. A connecting bracket, one end of which is vertically connected to one side of the top of the vertical bracket, and the other end of which is vertically connected to the middle of the longitudinal bracket; The longitudinal support is equipped with a second probe, which is used to scan for damage to the longitudinal section of the weld between the rail head and the rail base, as well as at the rail web.

5. The rail weld flaw detection robot according to claim 4, characterized in that, Also includes: The force control sensor is located between one end of the robotic arm and the top of the vertical support.

6. The rail weld flaw detection robot according to claim 4, characterized in that, The vertical support includes: A cylindrical component, wherein a spring is provided in the cylindrical cavity, and a limiting post is provided on the inner wall of the cylindrical cavity; The telescopic component is movably inserted into the lower end of the cylindrical component, the top end of the telescopic component abuts against the lower end of the spring, and a limiting groove is provided on the side wall of the telescopic component, and the limiting post is inserted into the limiting groove. A floating joint is located at the bottom of the telescopic component, and the bottom end of the floating joint is connected to the first probe.

7. The rail weld flaw detection robot according to claim 4, characterized in that, The longitudinal support includes: A rectangular plate with a perforated structure in the middle; A pair of pulleys are respectively mounted on longitudinal supports at both ends of the slot, the pulleys are rotatably connected to the ends of the longitudinal supports, and a toothed belt is connected between the two pulleys; The second probe includes a transmitter and a receiver. Both the transmitter and the receiver have slots on their bottom sides. The transmitter and the receiver are slidably engaged with the slots on the sides of the longitudinal support's perforated structure. A first through hole is provided on one side of the transmitter, and a second through hole is provided on the outside of the receiver opposite to the first through hole. The toothed belt passes through the first through hole on one side and the second through hole on the other side. The transmitter side in the first through hole and the receiver side in the second through hole are respectively provided with teeth that mesh with and drive the toothed belt. The drive pulley can realize the relative or opposite movement of the transmitter and the receiver.

8. The rail weld flaw detection robot according to claim 7, characterized in that, A knob is provided on any of the pulleys or a drive motor is connected and installed to drive it.

9. A method for inspecting rail welds of a robot according to claim 1, characterized in that, Includes the following steps: The platform moves along the rail, and the rail welds on one side are first scanned and inspected. After the rail welds on one side are scanned, the probe is moved and adjusted to scan the rail welds on the other side. For weld seam positioning, the traveling platform stops when the probe moves to a position near the weld seam. The weld seam positioning method uses a sliding table for positioning. When the sliding table moves with the traveling platform to the weld seam position, the end of the sliding table is exactly aligned with the weld seam, at which point the traveling platform stops. The controller manipulates the robotic arm and slide to drive the probe to perform a comprehensive scan and flaw detection of the weld.

10. The rail weld flaw detection method according to claim 9, characterized in that, Includes the following steps: Rail bottom inspection: Taking the weld as the object, the rail bottom inspection is divided into four longitudinal sections. The inspection paths for the four longitudinal sections are inner rail bottom upward, inner rail bottom downward, outer rail bottom upward, and outer rail bottom downward, and the inspection process for the four longitudinal sections is the same, as follows: The rail base is divided into four sections, with distances of 15mm, 23mm, 38mm, and 53mm from the rail base respectively. First, at the first gear, 15mm from the rail base, start from 50-150mm from the weld. Use a serrated scan to scan towards the weld, then return to the starting position. Next, use an angled scan, moving towards the weld with an inward 5° angle. Then, move towards the weld with an outward 5° angle. Next, at the second gear, 23mm from the rail base, starting from 50-150mm from the weld, first use a serrated scan, scanning towards the weld; then use an angled scan, moving towards the weld with an inward 5° skew; then move towards the weld with an outward 5° skew. Then, at position 38mm from the rail base, starting from 50-150mm from the weld, first use a serrated scan, scanning towards the weld; then use an angled scan, moving towards the weld with an inward 8-10° skew; then move towards the weld with an outward 8-10° skew. Next is the fourth gear, 53mm from the bottom of the rail. Starting from 50-150mm from the weld, first use a serrated scan to scan towards the weld; then use an angled scan, moving towards the weld with an inward 8-10° skew; then move towards the weld with an outward 8-10° skew. Finally, starting from the middle position of gear 1-2, 150mm away from the weld, a large-angle sweep is performed towards the bottom weld bead of the diagonally opposite side rail. Rail surface scanning: The first probe scans the rail surface in two longitudinal sections. The scanning paths for the two longitudinal sections are upward and downward, respectively, and the scanning process for the two longitudinal sections is the same, as follows: Starting from the centerline of the rail surface, and 250mm from the weld, the scanner moves 250mm closer to the weld with a 0° skew angle. After scanning, it returns to the starting position. Then, it moves 250mm closer to the weld with an inward skew angle of 8°. Finally, it moves 250mm closer to the weld with an outward skew angle of 8°. Then, the probe is shifted to both the inner and outer sides of the rail, but each shift must ensure a 15% overlap with the previous scan until the rail surface is completely covered. After each shift, the probe is moved 250mm from 250mm away from the weld with a 0° skew angle towards the weld. Then, it is moved 250mm with an inward skew angle of 8° towards the weld, and then 250mm with an outward skew angle of 8° towards the weld. The second probe's rail surface scanning: The transmitter and receiver are both located at the two ends of the slot. An alignment line is provided on the rectangular plate on the side of the transmitter facing the receiver. When the longitudinal support is used for scanning, the probe is located at the center line of the rail surface. During use, the alignment line needs to be aligned with the left edge, center line, and right edge of the weld seam for three scans. During scanning, the drive pulley moves the transmitter and receiver at both ends relative to each other until the transmitter passes the weld seam.

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