Intelligent railway wheel set pushing device and control method thereof

Abstract

The invention discloses an intelligent railway wheel set pushing device and a control method thereof. The intelligent railway wheel set pushing device comprises an AGV trolley, a pair of wheel set lifting assemblies, a visual module and a movement detection assembly. Each wheel pair lifting assembly comprises a jacking push rod, a fixing plate and two rolling wheels; each movement detection assembly comprises a stroke limiting switch and a steering engine assembly, and the stroke limiting switches and the visual module are electrically connected with a main controller. The invention further comprises a control method of S1-S9. According to the cooperative control method of the intelligent railway wheel set pushing device, through a two-stage control strategy of visual coarse guidance and contact type fine positioning, the intelligence of large-range search and the absolute reliability of final positioning are achieved at the same time. The visual module is matched with the mechanical contact switch, millimeter-level precision and anti-interference capability in the positioning process are guaranteed, the millimeter-level precision and the anti-interference capability are complementary, efficient, high-precision and high-reliability automatic operation in a complex industrial scene is achieved, and the structure is simple, compact, stable and reliable.

Description

Technical Field

[0001] This invention relates to the field of railway vehicle maintenance technology, and in particular to an intelligent wheelset pushing device and its control method. Background Technology

[0002] As the core load-bearing component of the running gear of railway vehicles, the quality of wheel sets maintenance directly affects the safety of train operation. During the maintenance process, wheelsets need to move between multiple positions such as measurement, pressing, and flaw detection. The efficiency and safety of this cross-position transportation link directly affect the overall capacity and operational safety of the maintenance line.

[0003] In the existing vehicle depot maintenance workshop, wheelset transportation across work stations is still mainly done manually. While this meets basic turnover needs, with increasing maintenance volume and upgraded safety standards, multiple pain points related to efficiency, safety, and personnel health are gradually being exposed. Existing alternative devices are also difficult to adapt to actual needs due to functional limitations. The wheelset pushing scenario in the pressing room further amplifies the drawbacks of manual transportation and still has the following problems: 1. Press-fitting is a critical step in wheelset maintenance. After all wheelset axle boxes are pressed-fitted on the same day, the wheelsets, after being treated with the same temperature, are pushed to the next work station. At this point, the workers have already completed a full day of high-intensity press-fitting work and are physically exhausted. However, pushing this batch of wheelsets requires the coordinated efforts of four workers: two in front to pull and control the direction, and two in behind to stabilize the wheelsets and prevent them from deviating. The entire process takes about an hour to complete. This "exhausted state + high-intensity collaboration" model not only significantly increases labor costs but also leads to low pushing efficiency due to the physical exhaustion of the workers. This often results in delays in completing the maintenance tasks for the day, greatly reducing the capacity of the wheelset maintenance line. Moreover, manual pushing also poses significant safety hazards and occupational health risks.

[0004] 2. To prevent wheelsets from slipping during pushing and stationary operation, wheel stoppers must be manually removed and placed before and after each wheel operation. However, since there are no fixed storage locations for wheel stoppers at each workstation, operators must frequently run between different workstations to retrieve and deliver them. This makes it difficult to achieve standardized management of wheel stoppers and easily leads to wheelsets slipping due to omissions or positional deviations. This can result in minor damage to the wheelsets from collisions with equipment, or even endanger the personal safety of nearby workers. In recent years, there have been several incidents of minor wheelset slippage caused by improper placement of wheel stoppers. Furthermore, repeatedly bending over and stooping while retrieving and placing wheel stoppers can easily lead to occupational health problems such as lumbar strain and lumbar muscle strain for workers over long periods, placing extremely high demands on the physical fitness of personnel and increasing the company's occupational health management costs.

[0005] 3. The industry has attempted to use AGVs (Automated Guided Vehicles) to replace manual labor. AGVs can achieve unmanned transportation of wheelsets based on automatic navigation technology, but their limitations are also obvious: AGVs are mostly standardized designs and are only suitable for single-station transportation with fixed paths and simple operating scenarios. However, the layout of positions in the Wuxi maintenance depot is complex. Wheelset pushing needs to adapt to distances of 3-30 meters and requires frequent switching to different process positions such as gauging, pressing, and flaw detection. The fixed path planning of AGVs is difficult to cope with the flexible transportation needs of multiple positions and variable distances. When scheduling across positions, waiting congestion is likely to occur, which will reduce transportation efficiency and cannot meet the core requirement of dynamic wheelset movement with process flow. Summary of the Invention

[0006] To address the aforementioned shortcomings of existing technologies, this invention provides an intelligent railway wheelset pushing device and its control method, which automatically completes wheelset positioning, lifting, transportation, and unloading operations, thereby improving the working efficiency of wheelset maintenance lines.

[0007] To achieve the above-mentioned objectives, the technical solution adopted by this invention is as follows: A railway wheelset intelligent pushing device and its control method are provided, including an AGV trolley, a pair of wheelset lifting components mounted on the AGV trolley, and a vision module located at the front of the AGV trolley. The vision module includes a vision sensor, and a movement detection component is provided on the side of each wheelset lifting component. Each wheelset lifting component includes a lifting rod fixed on the AGV trolley, a fixed plate fixed to the telescopic end of the lifting rod, and two rollers mounted on the fixed plate. The two rollers are used to limit the wheelset axle of the wheelset. Each roller is rotatably mounted on the fixed plate through two bearing supports. Each movement detection component includes a travel limit switch. A servo motor component is provided on the AGV trolley to drive the travel limit switch to rotate. The travel limit switch and the vision module are electrically connected to a main controller.

[0008] Furthermore, the servo motor assembly includes a servo motor and a connecting plate for mounting travel limit switches. The output end of the servo motor is fixed to the connecting plate via a metal servo disc. A servo motor mounting bracket is fixed on the AGV trolley for mounting the servo motor.

[0009] Furthermore, two guide components are provided between each fixed plate and the AGV trolley, and the two guide components are evenly distributed on both sides of the lifting push rod.

[0010] Furthermore, the guide assembly includes a linear bearing mounting bracket fixed on the AGV trolley and a linear bearing fixed on the linear bearing mounting bracket, with a guide steel column that mates with the linear bearing fixed at the bottom of the mounting plate.

[0011] Furthermore, the servo motor assembly drives the travel limit switch to rotate within the horizontal and vertical positions.

[0012] A control method for a railway wheelset intelligent pushing device includes the following steps: S1: The system is powered on, and the visual sensor and main controller are initialized, as well as the preset key parameters of the intelligent push device for railway wheelsets are loaded. S2: The AGV identifies the target wheelset through a vision sensor, performs coarse positioning and pre-alignment of the target wheelset, and the main controller controls the AGV to perform coarse positioning movement. S3: Based on real-time acquired images from the front Get the pixel width of the wheelset image and physical distance Based on the real-time obtained wheelset image pixel width and physical distance The main controller determines the threshold value based on the preset threshold. and switching threshold Switch the AGV to mechanical sensing mode; S4: When the AGV switches to mechanical sensing mode, the main controller controls the travel limit switch to move to the vertical detection state. At the same time, the main controller controls the AGV to perform precise positioning and movement operations. The AGV speed is reduced to crawling speed, and the vision sensor switches to monitoring state to provide data for possible anomaly handling. S5: The AGV trolley performs precise positioning and movement, and the AGV trolley moves to the lifting working position in conjunction with the travel limit switch; S6: After the AGV trolley reaches the lifting working position, it stops. At this time, the main controller controls the travel limit switch to rotate to the horizontal position, ready to carry out the wheel lifting operation. S7: The main controller adjusts the lifting target height according to... The lifting push rod controls the lifting operation of the wheelset; the built-in encoder of the lifting push rod provides real-time height feedback. The main controller adjusts the height based on real-time feedback. Determine the lifting position of the lifting push rod, and then use the lifting push rod to lift the wheelset; S8: The lifting push rod lifts and supports the wheelset through the rollers. After the rollers make stable contact with the wheelset axle, the AGV trolley drives the wheelset to move to the target position. S9: After the AGV transports the wheelset to the target position, the main controller controls the lifting push rod to end the lifting operation. After the lifting push rod is retracted to the minimum stroke, the stroke limit switch returns to the vertical detection state. After the AGV moves out of the lifting position along the original path, steps S2-S9 are repeated to carry out the next wheelset transfer task.

[0013] Furthermore, step S1 specifically includes the following steps: S110: System power-on; S120: Initialization of the vision module: Load the pre-calibrated intrinsic parameter matrix of the vision sensor. and distortion coefficient ; S130: Main controller initialization: Loading the coordinate system of the vision sensor coordinate system with AGV vehicle body Rotation matrix between With translation vector ; S140: Preset key parameters include the standard radius of the wheelset axle. The preset safety clearance between the roller cross-section and the target lifting position of the wheelset axle The initial height of the roller when the lifting push rod reaches its minimum stroke. The horizontal installation offset between the trigger surface of the travel limit switch and the center line of the roller .

[0014] Furthermore, step S2 specifically includes the following steps: S21: The vision sensor continuously acquires images from the front. , the image in front Using distortion coefficient Corrected image and delineate the image in front. Region of Interest (ROI) corresponding to the central ground region; S22: Process the image of the region of interest (ROI), identify the target wheelset, and obtain the bounding rectangle of the wheelset axle within the ROI. Use the midpoint of the bottom edge of the bounding rectangle as the approximate projection point of the corresponding wheelset axle on the ground. And calculate the approximate projection point. pixel coordinates , For approximate projection points x-coordinate For approximate projection points The ordinate; S23: Approximate projection points pixel coordinates Transform the model to the AGV vehicle's body coordinate system. Obtain three-dimensional coordinates 3D coordinate points The coordinates are , Three-dimensional coordinate points In the coordinate system of the AGV vehicle body In Axis coordinates Three-dimensional coordinate points In the coordinate system of the AGV vehicle body In Axis coordinates Three-dimensional coordinate points In the coordinate system of the AGV vehicle body In Axis coordinates; the specific transformation model is as follows: ; In the formula, For approximate projection points In the visual sensor coordinate system The three-dimensional coordinates below; The depth information scale factor is set; Intrinsic parameter matrix of visual sensor The inverse matrix, Rotation matrix The transpose of the matrix, Visual sensor coordinate system To the coordinate system of the AGV vehicle body The rotation matrix, Visual sensor coordinate system To the coordinate system of the AGV vehicle body Translation vector, three-dimensional coordinates Translation vector Obtained through hand-eye calibration. Let x be the x-coordinate of the wheelset axle center point in the image pixel coordinate system. Let be the ordinate of the center point of the wheelset axle in the image pixel coordinate system. For visual sensors on the imaging plane Focal length along the axial direction, For visual sensors on the imaging plane Focal length along the axial direction, Let x be the x-coordinate of the principal projection point. The ordinate of the principal projection point; S24: Calculate the wheelset axle center in the coordinate system Lateral offset Deviation from the center line of the car As a lateral offset, the main controller controls the AGV to adjust its heading, aligning the AGV's centerline with the center projection direction of the wheel axle. The X-axis of the coordinate system is used by the main controller to control the AGV trolley along... The direction is used for coarse positioning and movement.

[0015] Furthermore, in step S3, when the real-time obtained wheelset image width and physical distance... When at least one condition is met, the main controller switches the AGV to mechanical sensing mode. The specific conditions are: Real-time frontal image The pixel width of the wheel pair image Greater than the preset threshold At that time, the main controller controls the AGV to switch to mechanical sensing mode; when the real-time image ahead... The pixel width of the wheel pair image Less than or equal to the preset threshold At this time, the AGV trolley does not switch to mechanical sensing mode; When the physical distance estimated by the visual sensor Less than the switching threshold When the main controller switches the AGV to mechanical sensing mode, the visual sensor estimates the physical distance. Greater than or equal to the switching threshold At this time, the AGV trolley does not switch to mechanical sensing mode.

[0016] The beneficial effects of this invention are as follows: This invention employs a lifting push rod, with the assistance of a linear bearing for limiting the position. This not only allows the lifting push rod to rise in a specified direction, but also, due to the cooperation of the linear bearing and the guide steel column, the lifting push rod can withstand lateral thrust to a certain extent, ensuring that the force generated at the moment the roller contacts the wheelset axle can be distributed to the linear bearing and the guide steel column.

[0017] This invention is also equipped with a travel limit switch, which is linked with the lifting assembly. The moment the wheel axle touches the travel limit switch, the vehicle stops, the push rod lifts up, and the operation is completed. Furthermore, the mechanism exhibits good overall stress distribution, high reliability, simple operation, and advantages such as small size, light weight, and low power consumption.

[0018] The intelligent railway wheelset pushing device and control method of this invention, through a two-stage control strategy combining visual coarse guidance with contact-based fine positioning, achieves both the intelligence of wide-range searching and the absolute reliability of final positioning. The vision module solves the problems of initial alignment and efficiency, while the mechanical contact switch ensures millimeter-level accuracy and anti-interference capability (unaffected by light or oil) during the positioning process. The vision system and the mechanical contact switch complement each other, realizing a simple, compact, stable, and reliable automated operation structure for complex industrial scenarios. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a partial structural schematic diagram of the present invention; Figure 3 This is a schematic diagram illustrating the operation of the present invention; The symbols for the main components in the diagram are explained below: 1. Limit switch; 2. Roller; 3. Bearing support; 4. Connecting plate; 5. Metal steering wheel; 6. Steering motor; 7. Steering motor mounting bracket; 8. Base plate; 9. Fixing plate; 10. Linear bearing; 11. Lifting push rod; 12. Guide steel column; 13. Linear bearing mounting bracket; 14. Vision sensor; 15. AGV trolley; 16. Wheelset. Detailed Implementation

[0020] The specific embodiments of the present invention are described below to enable those skilled in the art to understand the present invention. However, it should be understood that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the present invention as defined and determined by the appended claims. All inventions utilizing the concept of the present invention are protected.

[0021] like Figure 1 , 2 As shown in Figure 3, the intelligent pushing device for railway wheelsets includes an AGV trolley 15, a pair of wheelset lifting assemblies mounted on the AGV trolley 15, and a vision module located at the front of the AGV trolley 15. The vision module includes a vision sensor 14, and a movement detection assembly is provided on the side of each wheelset lifting assembly. Each wheelset lifting assembly includes a lifting push rod 11 fixed on the AGV trolley 15, a fixing plate 9 fixed to the telescopic end of the lifting push rod 11, and two rollers 2 mounted on the fixing plate 9. The two rollers 2 are used to limit the wheelset axle of the wheelset 16. Each roller 2 is rotatably mounted on the fixing plate 9 through two bearing supports 3. Each movement detection assembly includes a travel limit switch 1. A servo motor assembly is provided on the AGV trolley 15 to drive the travel limit switch 1 to rotate. The travel limit switch 1 and the vision module are electrically connected to a main controller.

[0022] The servo assembly includes a servo motor 6 and a connecting plate 4 for mounting the travel limit switch 1. The output end of the servo motor 6 is fixed to the connecting plate 4 via a metal servo disc 5. A servo motor mounting bracket 7 for mounting the servo motor 6 is fixed on the AGV trolley 15. Two guide components are provided between each mounting plate 9 and the AGV trolley 15, evenly distributed on both sides of the lifting push rod 11. The guide components include a linear bearing mounting bracket 13 fixed on the AGV trolley 15 and a linear bearing 10 fixed on the linear bearing mounting bracket 13. A guide steel column 12 that mates with the linear bearing 10 is fixed to the bottom of the mounting plate 9. The servo assembly drives the travel limit switch 1 to rotate within horizontal and vertical positions.

[0023] A control method for a smart wheelset pushing device for railways includes the following steps: S1: The system powers on, initializes the vision sensor and main controller, and loads the preset key parameters of the intelligent railway wheelset pushing device. The main controller uses an STM32 control board; specifically: S110: System power-on; S120: Initialization of the vision module: Load the pre-calibrated intrinsic parameter matrix of the vision sensor 14. and distortion coefficient ; Intrinsic parameter matrix as follows: ; In the formula, For visual sensor 14 in On-axis focal length, For visual sensor 14 in On-axis focal length; The x-coordinate of the optical center of the vision sensor 14 on the image plane. The vertical coordinate of the optical center of the vision sensor 14 on the image plane; S130: Main controller initialization: Load the extrinsic parameter matrix obtained through "hand-eye calibration". The extrinsic parameter matrix is ​​obtained from the visual sensor coordinate system. The rotation and translation parameters transformed to the robot end-tool coordinate system, including the rotation matrix, are extrinsic parameters. With translation vector The extrinsic parameter matrix is ​​in the 14-coordinate system of the vision sensor. To the coordinate system of the AGV vehicle body The transformation relationship; S140: Preset Key Parameters Loading: Preset key parameters include the standard radius of the wheelset axle. The preset safety clearance between the tangential surface of roller 2 and the target lifting position of the wheelset axle. ( Preferably 2-5mm), the initial height of roller 2 when the lifting push rod 11 has its minimum stroke. The horizontal installation offset between the trigger surface of the travel limit switch 1 and the center line of the roller 2 ; S2: The AGV trolley 15 identifies the target wheelset through the vision sensor 14, performs coarse positioning and pre-alignment of the target wheelset, and the main controller controls the AGV trolley 15 to perform coarse positioning movement operations; specifically: S21: Vision sensor 14 continuously acquires images from the front. , the image in front Using distortion coefficient Corrected image and delineate the image in front. Region of Interest (ROI) corresponding to the central ground region; S22: Process the image of the region of interest (ROI), identify the target wheelset, and obtain the bounding rectangle of the wheelset axle within the ROI. Use the midpoint of the bottom edge of the bounding rectangle as the approximate projection point of the corresponding wheelset axle on the ground. And calculate the approximate projection point. pixel coordinates , For approximate projection points x-coordinate For approximate projection points The vertical coordinate; wheel pair targets can be identified using a lightweight target detection model based on deep learning (such as the YOLO series) or a traditional image algorithm for metal cylinders (edge ​​detection + Hough transform). S23: Approximate projection points pixel coordinates Transform the model to the AGV vehicle's body coordinate system. Obtain three-dimensional coordinates 3D coordinate points The coordinates are , Three-dimensional coordinate points In the coordinate system of the AGV vehicle body In Axis coordinates Three-dimensional coordinate points In the coordinate system of the AGV vehicle body In Axis coordinates Three-dimensional coordinate points In the coordinate system of the AGV vehicle body In Axis coordinates; the specific transformation model is as follows: ; In the formula, For approximate projection points In the visual sensor 14 coordinate system The three-dimensional coordinates below; For the depth information scale factor, since the ground is flat, a preset depth value can be initially assumed. Alternatively, the calculation can be performed using geometric relationships based on the known wheelset axle diameter and pixel width in the image; 14 intrinsic parameter matrices for visual sensors The inverse matrix, Rotation matrix The transpose of the matrix, For the visual sensor 14 coordinate system To the coordinate system of the AGV vehicle body The rotation matrix, For the visual sensor 14 coordinate system To the coordinate system of the AGV vehicle body Translation vector, three-dimensional coordinates Translation vector Obtained through hand-eye calibration. Let x be the x-coordinate of the wheelset axle center point in the image pixel coordinate system. Let be the ordinate of the center point of the wheelset axle in the image pixel coordinate system. For the visual sensor 14 on the imaging plane Focal length along the axial direction, For the visual sensor 14 on the imaging plane Focal length along the axial direction, Let x be the x-coordinate of the principal projection point. The ordinate of the principal projection point; S24: Calculate the wheelset axle center in the coordinate system Lateral offset With respect to the centerline of the AGV (i.e., the coordinate system of the AGV body) of axis, deviation The deviation amount As a lateral offset, the main controller controls the AGV to adjust its heading, aligning the AGV's centerline with the center projection direction of the wheel axle. In this invention, the AGV's centerline corresponds to... The X-axis of the coordinate system is used by the main controller to control the AGV trolley along... Perform coarse positioning and movement operations in the direction; S3: Based on real-time acquired images from the front Get the pixel width of the wheelset image and physical distance Combined with preset threshold and switching threshold The main controller switches the AGV trolley 15 to mechanical sensing mode; Specifically, when the AGV trolley 15 approaches the wheelset to a critical distance via visual guidance, the main controller switches the travel limit switch to a higher-precision mechanical sensing mode; when the real-time obtained wheelet image width and physical distance... When at least one condition is met: Real-time frontal image The pixel width of the wheel pair image Greater than the preset threshold At that time, the main controller controls the AGV trolley 15 to switch to mechanical sensing mode; when the real-time front image The pixel width of the wheel pair image Less than or equal to the preset threshold At that time, AGV trolley 15 does not switch to mechanical sensing mode; When the physical distance is estimated by the vision sensor 14 Less than the switching threshold When the main controller controls the AGV trolley 15 to switch to mechanical sensing mode; when the vision sensor 14 estimates the physical distance... Greater than or equal to the switching threshold At that time, AGV trolley 15 does not switch to mechanical sensing mode; S4: When the AGV trolley 15 switches to the mechanical sensing mode, the main controller controls the travel limit switch 1 to move to the vertical detection state. At the same time, the main controller controls the AGV trolley to perform precise positioning and movement operations. The AGV trolley reduces its speed to the crawling speed, and the vision sensor 14 is in the monitoring state mode to provide data for possible abnormal handling. S5: The AGV trolley 15 performs precise positioning and movement. The AGV trolley 15 moves to the lifting working position in coordination with the travel limit switch 1. Specifically, this stage relies on highly reliable mechanical contact sensing to complete the final positioning and action. The AGV continues to move forward at a low crawling speed until the spring rod of the travel limit switch 1 contacts the side of the wheel shaft and is triggered. The high-level signal generated by the travel limit switch 1 is sent to the main controller as a hardware interrupt, and the main controller controls the AGV to stop. S6: After the AGV trolley 15 reaches the lifting working position, it stops. At this time, the main controller controls the travel limit switch 1 to rotate to the horizontal position, in preparation for the lifting operation of the wheelset 16. Specifically, the servo motor 6 is controlled to rotate, and the servo motor 6 drives the connecting plate 4 through the metal servo disk 5 to retract the travel limit switch 1 from the vertical state to the horizontal state parallel to the base plate 8, so as to avoid interference with subsequent lifting. S7: The main controller adjusts the lifting target height according to... The built-in encoder of the lifting push rod 11 provides real-time height feedback. The lifting push rod 11 is controlled to lift the wheelset 16. Specifically: The main controller controls the lifting push rod 11 to rise. When the lifting push rod 11 is activated, in conjunction with the guiding action of the linear bearing 10 and the guide steel column 12, it drives the fixed plate 9 and roller 2 to rise vertically to the target height. The calculation formula is as follows: ; The actual radius of the wheelset axle (can be a standard value or estimated by measuring with a distance sensor before and after contact). The preset safety clearance between the roller cross-section and the target lifting position of the wheelset shaft ( (Preferably 2-5mm) to ensure that the roller and the wheel set axle make line contact rather than point collision after lifting; This is the initial height of the roller when the lifting push rod has reached its minimum stroke; The main controller adjusts the height based on real-time feedback. The specific method for determining the lifting position of the lifting push rod 11 is as follows: when hour, For tolerance, If the value is 0.3mm, it is determined that the lifting push rod 11 has not been lifted to the correct position, and the main controller controls the lifting push rod 11 to continue the lifting operation; when Once it is determined that the lifting push rod 11 has been lifted to the correct position, the main controller controls the lifting push rod 11 to stop the lifting operation. S8: The lifting push rod 11 lifts and supports the wheelset 16 through the roller 2. After the roller 2 makes stable contact with the wheelset axle, the AGV trolley drives the wheelset 16 to the target position. After a brief delay, the system monitors whether the drive motor current is within the expected load range to confirm that the wheelset has been reliably lifted. The control system controls the trolley to transport the wheelset to the target workstation along a predetermined path (QR code navigation) at a set safe transport speed. During transport, the vision system can work intermittently to monitor whether the wheelset has deviated unexpectedly and provide feedback to the remote control status indicator. S9: After the AGV trolley 15 transports the wheelset 16 to the target position, the main controller controls the lifting push rod 11 to end the lifting operation. After the lifting push rod 11 is retracted to the minimum stroke, the stroke limit switch 1 returns to the vertical detection state. After the AGV trolley moves out of the lifting position along the original path, steps S2-S9 are repeated to carry out the next wheelset transfer task. Specifically, when the AGV stops at the target position, the main controller controls the lifting push rod 11 to descend to its minimum stroke, and the lifting push rod 11 smoothly places the wheelset on the target track or bracket; after the lifting push rod 11 descends to its minimum stroke, it controls the servo motor 6 to rotate in the opposite direction, resetting the stroke limit switch 1 to the vertical detection state; the AGV moves to the starting search point of the next wheelset to be pushed, the system status is cleared, and it automatically jumps to step S2 to start a new round of operation cycle.

Claims

1. A railway wheel set intelligent pushing device, characterized in that, The application relates to an AGV trolley (15), a pair of wheel-pair lifting assemblies installed on the AGV trolley (15) and a vision module arranged on the front side of the AGV trolley (15), wherein the vision module comprises a vision sensor (14), and a movement detection assembly is arranged on the side of each wheel-pair lifting assembly. Each wheel-pair lifting assembly comprises a jacking push rod (11) fixed on the AGV trolley (15), a fixed plate (9) fixed on the telescopic end of the jacking push rod (11) and two rollers (2) installed on the fixed plate (9), the two rollers (2) are used for limiting wheel-pair shafts of wheel pairs (16), and each roller (2) is rotatably installed on the fixed plate (9) through two bearing supports (3). Each movement detection assembly comprises a stroke limit switch (1), a rudder assembly is arranged on the AGV trolley (15) and drives the stroke limit switch (1) to rotate, and the stroke limit switch (1) and the vision module are electrically connected with a main controller.

2. The railway wheel set intelligent pushing device according to claim 1, characterized in that, The rudder assembly comprises a rudder (6) and a connecting plate (4) on which the stroke limit switch (1) is installed, the output end of the rudder (6) is fixedly connected with the connecting plate (4) through a metal rudder disc (5), and the AGV trolley (15) is fixedly provided with a rudder fixing support (7) on which the rudder (6) is installed.

3. The railway wheel set intelligent pushing device according to claim 2, characterized in that, Two guide assemblies are arranged between each fixed plate (9) and the AGV trolley (15), and the two guide assemblies are evenly arranged on the two sides of the jacking push rod (11).

4. The railway wheel set intelligent pushing device according to claim 3, characterized in that, The guide assembly comprises a linear bearing fixing support (13) fixed on the AGV trolley (15) and a linear bearing (10) fixed on the linear bearing fixing support (13), and the bottom of the fixed plate (9) is fixedly provided with a guide steel column (12) matched with the linear bearing (10).

5. The railway wheelset intelligent pushing device according to claim 4, characterized in that, The stroke limit switch (1) is driven by the rudder assembly to rotate in the horizontal position and the vertical position.

6. A control method for the railway wheel set intelligent pushing device according to any one of claims 1-5, characterized in that, The application further discloses a railway wheel-pair intelligent pushing method, and comprises the following steps: S1: system power-on, initialization of the vision sensor (14) and the main controller, and preset key parameter loading of the railway wheel-pair intelligent pushing device; S2: the AGV trolley (15) identifies a target wheel pair through the vision sensor (14), performs coarse positioning and pre-alignment of the target wheel pair, and the main controller controls the AGV trolley (15) to perform coarse positioning movement; S3: according to the real-time collected front image Obtain wheel pair image pixel width And physical distance , according to the real-time obtained wheel pair image pixel width And physical distance , the main controller switches the AGV trolley (15) to the mechanical sensing mode according to the preset threshold And switching threshold ; S4: when the AGV trolley (15) is switched to a mechanical sensing mode, the main controller controls the stroke limit switch (1) to move to a vertical detection state, meanwhile, the main controller controls the AGV trolley (15) to perform fine positioning movement, the AGV trolley (15) reduces the speed to a crawling speed, and the vision sensor (14) is switched to a monitoring state to provide data for possible abnormal treatment; S5: the AGV trolley (15) performs fine positioning movement, and the AGV trolley (15) moves to a jacking working position in cooperation with the stroke limit switch (1); S6: the AGV trolley (15) stops after reaching the jacking working position, at this moment, the main controller controls the stroke limit switch (1) to rotate to the horizontal position, and prepares to perform wheel-pair (16) jacking operation. S7: The main controller controls the jacking push rod (11) to perform jacking operation on the wheel set according to the jacking target height The built-in encoder of the jacking push rod (11) feeds back the height in real time The main controller judges the jacking position of the jacking push rod (11) according to the real-time feedback height and performs jacking operation on the wheel set (16) through the jacking push rod (11) S8: The jacking push rod (11) completes the lifting of the wheel set (16) through the roller (2), and after the roller (2) is in stable contact with the wheel set shaft, the AGV (15) drives the wheel set (16) to move to the target position; S9: After the AGV (15) transports the wheel set (16) to the target position, the main controller controls the jacking push rod (11) to end the jacking operation, and after the jacking push rod (11) is retracted to the minimum stroke, the stroke limit switch (1) returns to the vertical detection state, and the AGV (15) moves out of the jacking position in the original way, and repeats steps S2-S9 to perform the next wheel set transfer task.

7. The railway wheel set intelligent pushing device and control method thereof according to claim 6, characterized in that, Step S1 specifically includes the following steps: S110: The system is powered on; S120: initialization of vision module: load intrinsic matrix of vision sensor (14) calibrated beforehand and distortion coefficients ; S130: Initialization of the master controller: loading of the coordinate system of the vision sensor (14) Rotation matrix between the AGV cart (15) body coordinate system Translation vector ;​ S140: the preset key parameters include the standard radius of the wheelset shaft , the preset safety clearance between the wheel (2) section surface and the target position of the wheelset shaft jacking , the initial height of the wheel (2) when the jacking push rod (11) has the minimum stroke , and the horizontal installation offset amount of the triggering surface of the stroke limiting switch (1) and the center line of the wheel (2) .

8. The railway wheel set intelligent pushing device and control method thereof according to claim 6, characterized in that, In step S2, specifically includes the following steps: S21: the visual sensor (14) continuously collects the front image , the front image is corrected by using the distortion coefficient to obtain the corrected image , and the ground region in the front image is demarcated as a region of interest (ROI). S22: Process the image of the region of interest (ROI), identify the target wheelset, and obtain the bounding rectangle of the wheelset axle within the ROI. Use the midpoint of the bottom edge of the bounding rectangle as the approximate projection point of the corresponding wheelset axle on the ground. And calculate the approximate projection point. pixel coordinates , For approximate projection points x-coordinate For approximate projection points The ordinate; S23: the pixel coordinate of the approximate projection point converted to the AGV body coordinate system by a conversion model , the coordinate of the three-dimensional coordinate point , the z-axis coordinate of the three-dimensional coordinate point in the AGV body coordinate system , the z-axis coordinate of the three-dimensional coordinate point in the AGV body coordinate system , the z-axis coordinate of the three-dimensional coordinate point in the AGV body coordinate system , the z-axis coordinate of the three-dimensional coordinate point in the AGV body coordinate system ; the specific conversion model is as follows:​​​​​​ ； In the formula, is the approximate projection point Three-dimensional coordinates in the vision sensor (14) coordinate system ; is the set depth information scale factor; is the inverse matrix of the vision sensor (14) intrinsic matrix , is the transpose matrix of the rotation matrix , is the rotation matrix from the vision sensor (14) coordinate system to the AGV trolley body coordinate system , is the translation vector from the vision sensor (14) coordinate system to the AGV trolley body coordinate system , three-dimensional coordinates and translation vector are obtained through hand-eye calibration, is the horizontal coordinate of the wheel set shaft center point in the image pixel coordinate system, is the vertical coordinate of the wheel set shaft center point in the image pixel coordinate system, is the focal length of the vision sensor (14) in the imaging plane axis direction, is the focal length of the vision sensor (14) in the imaging plane axis direction, is the horizontal coordinate of the projection principal point, is the vertical coordinate of the projection principal point; S24: Calculate the wheelset axle center in the coordinate system Lateral offset Deviation from the center line of the car As a lateral offset, the main controller controls the AGV to adjust its heading, aligning the AGV's centerline with the center projection direction of the wheel axle. The X-axis of the coordinate system is used by the main controller to control the AGV trolley along... The direction is used for coarse positioning and movement.

9. The railway wheel set intelligent pushing device and control method thereof according to claim 6, characterized in that, In step S3, when the wheel pair image width and the physical distance When the judgment condition is met, the main controller switches the AGV trolley (15) to the mechanical sensing mode, and the specific judgment condition is: Real-time frontal image The pixel width of the wheel pair image Greater than the preset threshold At that time, the main controller controls the AGV (15) to switch to mechanical sensing mode; when the real-time front image The pixel width of the wheel pair image Less than or equal to the preset threshold At this time, the AGV (15) does not switch to mechanical sensing mode; When the physical distance estimated by the vision sensor (14) is less than a switching threshold , the main controller controls the AGV (15) to switch to a mechanical sensing mode; when the physical distance estimated by the vision sensor (14) is greater than or equal to the switching threshold , the AGV (15) does not switch to the mechanical sensing mode.

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