Automatic guided vehicle load device for liner tubing downhole material flow transfer and method

Abstract

This invention relates to the field of automated logistics and intelligent equipment, specifically to an automated guided vehicle (AGV) carrying device and method for conveying materials through pipes with reduced diameter inner-lined tubing. It includes an AGV chassis, a front support base, a rear support base, a lateral movement assembly, a lifting assembly, a clamping assembly, and a controller. The device has independent lateral movement and lifting assemblies configured on the front and rear support bases, enabling independent movement of the pipe support points in the horizontal and vertical directions. Its core is that the controller calculates and controls the differential lateral movement and differential lifting stroke of the actuators based on spatial position deviations, thereby achieving alignment of the pipe's yaw and pitch angles. This invention separates the docking action from the walking action, eliminating the need for overall reciprocating movement of the vehicle body, effectively overcoming the positioning error defects caused by ground unevenness and vehicle inertia interference in traditional methods.

Description

Technical Field

[0001] This invention relates to the field of automated logistics and intelligent equipment, specifically to an automated guided vehicle (AGV) carrying device and method for material transfer using inner-lined oil pipe with reduced diameter. Background Technology

[0002] When inner-lined tubing undergoes diameter reduction and insertion processing, ultra-long tubing requires long-distance transport and precise docking at workstations via transfer equipment. During the transport and extension stages, the tubing often experiences localized stress concentration and flexible bending deformation caused by center of gravity shift. For tubing handling and docking, existing solutions generally adopt a conventional integral structure, which relies on the overall reciprocating movement of an automated guided vehicle chassis or on external cranes and multi-axis robots for spatial orientation adjustment. Although this solution has the capability to handle transfers in dock handling scenarios, it is highly dependent on the overall structural handling and the proper functioning of external equipment. Furthermore, traditional gradient and support structures are prone to losing mechanical constraint under power outages or complex stress conditions, resulting in cumbersome attitude adjustment processes, significant interference from ground friction errors and vehicle inertia, and the tubing being prone to sliding, rolling, and surface scratching. It is also difficult to support millimeter-level independent centering adjustment before insertion processing and dynamic deflection compensation during the advancement stage.

[0003] Therefore, improving the stability of ultra-long pipes during the transfer and bearing process and the accuracy of spatial coordinate attitude adjustment has become a technical problem that needs to be solved in advance. Summary of the Invention

[0004] To solve the above-mentioned technical problems, the present invention provides an automatic guided vehicle carrying device and method for material transfer of inner-lined oil pipe with reduced diameter. Specifically, the technical solution of the present invention is as follows: An automated guided vehicle (AGV) carrying device for material transfer via a reduced-diameter inner-lined oil pipe includes: Automated Guided Vehicle (AGV) chassis; The front support base and the rear support base are respectively fixedly connected to both ends of the length direction of the top surface of the automated guided vehicle chassis; A transverse moving assembly is respectively disposed on the front bearing base and the rear bearing base, wherein the transverse moving assembly includes a transverse moving base plate and a transverse moving servo motor, and the transverse moving servo motor is used to drive the transverse moving base plate to move in the horizontal left and right directions; Lifting components are respectively disposed on the top surface of the transverse base plate, wherein the lifting components include a lifting inner cylinder and a lifting servo motor, and the lifting servo motor is used to drive the lifting inner cylinder to move in the vertical direction; Clamping assemblies are respectively disposed on the top surface of the lifting inner cylinder. The clamping assembly includes a bearing platform, a clamping servo motor, a left arc-shaped pressure arm and a right arc-shaped pressure arm. The clamping servo motor is used to drive the left arc-shaped pressure arm and the right arc-shaped pressure arm to slide towards each other. The controller is connected to an external position sensor to obtain the positional deviation between the center of the front end face of the pipe and the center of the target sleeve, and controls the transverse servo motor, the lifting servo motor and the clamping servo motor in real time accordingly.

[0005] In some embodiments, the clamping assembly further includes a worm gear reducer, a drive spur gear, a left rack, and a right rack; The output shaft of the clamping servo motor is connected to the worm gear reducer, and the output shaft of the worm gear reducer is fixedly connected to the drive spur gear. The left and right sides of the drive spur gear respectively mesh with the left rack and the right rack. The outer end of the left rack is vertically fixedly connected to the left arc-shaped pressure arm, and the outer end of the right rack is vertically fixedly connected to the right arc-shaped pressure arm.

[0006] In some embodiments, the traverse assembly further includes a traverse guide rail and a traverse ball screw; The top surface of the front bearing base is slidably connected to the transverse base plate via the transverse guide rail. The output shaft of the transverse servo motor is connected to the transverse ball screw via a plum blossom coupling. The nut flange of the transverse ball screw is fixed to the side wall of the transverse base plate.

[0007] In some embodiments, the lifting assembly further includes a lifting housing, a vertical guide rail, and a lifting ball screw; The top surface of the horizontal sliding base plate is fixedly connected to the lifting housing, the inner wall of the lifting housing is slidably connected to the lifting inner cylinder through the vertical guide rail, the output shaft of the lifting servo motor is connected to the lifting ball screw through a cross slider coupling, and the nut flange of the lifting ball screw is fixed to the bottom surface of the lifting inner cylinder.

[0008] In some embodiments, a V-shaped support groove is machined at the center of the top surface of the support platform; The left rack and the right rack are slidably connected to the top slide rail of the bearing platform via dovetail grooves.

[0009] In some embodiments, the concave surfaces of the left arc-shaped pressure arm and the right arc-shaped pressure arm are both fixedly connected to polyurethane anti-slip pads by countersunk screws. The thickness of the polyurethane anti-slip mat is 20mm.

[0010] The control method for the automatic guided vehicle carrying device for material transfer of inner-lined oil pipe with reduced diameter includes: S1. The operating current of the clamping servo motor is acquired in real time, and it is determined whether the operating current reaches the preset clamping current threshold and continues for a preset time. If it reaches the threshold, the power supply of the clamping servo motor is cut off. If it does not reach the threshold, the operating current of the clamping servo motor is acquired. If the clamping current threshold is not reached within the preset timeout period, the controller outputs an alarm signal to stop the operation. S2. Using the centerline of the target sleeve as the docking reference axis, the spatial position deviation between the center of the front end face of the pipe and the center of the target sleeve is obtained through an external position sensor to perform attitude differential calculation, and the differential lateral travel and differential lifting travel are calculated. S3. Control the transverse servo motors on the front and rear bearing bases to move synchronously in opposite directions according to the differential transverse stroke; S4. Control the lifting servo motors on the front support base and the rear support base to move synchronously in opposite directions according to the differential lifting stroke; S5. During the tube-driving and propulsion stage, the holding current required by the lifting servo motor on the front bearing base to maintain the current height of the inner cylinder is obtained in real time. The vertical sinking amount is calculated based on the increment of the holding current, and the lifting servo motor is controlled to output a compensation stroke equal to the vertical sinking amount upward.

[0011] In some embodiments, step S2 includes: determining the differential lateral travel and the differential lifting travel based on the horizontal offset distance, vertical offset distance, longitudinal distance from the center of the front end face of the pipe to the preset deflection rotation center, and the fixed center distance between the front bearing base and the rear bearing base in the spatial position deviation.

[0012] In some implementations, step S5 includes: S501. Obtain the reference current of the lifting component when there is no pipe load as the no-load operating current, and determine whether the increment of the holding current exceeds 10% of the no-load operating current; S502. If the value exceeds the limit, the vertical sinking amount of the pipe under the current stress state is determined based on the increment of the holding current, and the lifting servo motor is controlled to output a compensation stroke equal to the vertical sinking amount upward; if the value does not exceed the limit, the holding current is continuously acquired.

[0013] In some embodiments, the clamping assembly includes a worm gear reducer, a left rack, and a right rack; The specific steps of cutting off the power supply to the clamping servo motor in step S1 include: after cutting off the power supply to the clamping servo motor, mechanically locking the positions of the left rack and the right rack.

[0014] The present invention has the following beneficial effects: 1. This invention, by configuring a lateral movement component and a lifting component on the front and rear support bases of the automated guided vehicle chassis respectively, allows the front and rear support points of the pipe to move independently in the horizontal, left-right, and vertical directions. Combined with the differential lateral movement stroke and differential lifting stroke calculated and controlled by the controller based on the spatial position deviation, the alignment of the pipe's yaw and pitch angles can be completed without relying on the overall reciprocating movement of the vehicle body. This design separates the docking action from the reinforcement walking, overcoming the shortcomings of traditional methods that are affected by ground friction and vehicle inertia. 2. The clamping assembly of this invention clamps the pipe by driving the left and right arc-shaped pressure arms to slide towards each other. It also utilizes the reverse self-locking characteristic of the worm gear reducer to eliminate the radial rolling freedom of the pipe during travel. Combined with the polyurethane anti-slip pad, it effectively prevents the pipe from sliding and scratching its surface. In addition, during the pipe-passing and pushing stage, the controller calculates the vertical sinking amount by acquiring the holding current increment of the lifting assembly and controls the lifting servo motor to output the upward compensation stroke, realizing dynamic compensation for the sinking of the pipe under stress and enhancing the stability of the flow load. Attached Figure Description

[0015] The following drawings, illustrating embodiments of this application, are incorporated herein by reference and are used to understand this application. The drawings show embodiments of this application and their descriptions, serving to explain the principles of this application. In the drawings, Figure 1 This is a schematic diagram of the overall external structure of the device; Figure 2 This is a structural schematic diagram of the transverse component; Figure 3 This is a structural diagram of the lifting assembly; Figure 4 This is a schematic diagram of the arc-shaped pressure arm; Figure 5 This is a flowchart of the method of the present invention.

[0016] In the diagram: 100, Automated Guided Vehicle (AGV) chassis; 200, Front support base; 300, Rear support base; 400, Lateral movement assembly; 410, Lateral movement base plate; 420, Lateral movement servo motor; 430, Lateral movement guide rail; 440, Lateral movement ball screw; 450, L-shaped coupling; 500, Lifting assembly; 510, Lifting inner cylinder; 520, Lifting servo motor; 530, Lifting outer shell; 540, Vertical guide rail. 550. Lifting ball screw; 560. Cross-slider coupling; 600. Clamping assembly; 610. Bearing platform; 611. V-shaped support groove; 612. Dovetail groove; 620. Clamping servo motor; 630. Left arc-shaped pressure arm; 640. Right arc-shaped pressure arm; 650. Worm gear reducer; 660. Drive spur gear; 670. Left rack; 680. Right rack; 690. Polyurethane anti-slip mat. Detailed Implementation

[0017] In the following description, numerous specific details are set forth to provide a more thorough understanding of this application. However, it will be apparent to those skilled in the art that embodiments of this application may be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described to avoid confusion with embodiments of this application.

[0018] Example 1: An automated guided vehicle (AGV) carrying device for material transfer via a reduced-diameter inner-lined oil pipe includes: Automated Guided Vehicle Chassis 100; The front support base 200 and the rear support base 300 are respectively fixedly connected to the two ends of the top surface of the automated guided vehicle chassis 100 in the longitudinal direction; The transverse component 400 is respectively disposed on the front support base 200 and the rear support base 300. The transverse component 400 includes a transverse base plate 410 and a transverse servo motor 420. The transverse servo motor 420 is used to drive the transverse base plate 410 to move in the horizontal left and right directions. Lifting components 500 are respectively disposed on the top surface of the transverse base plate 410. The lifting components 500 include a lifting inner cylinder 510 and a lifting servo motor 520. The lifting servo motor 520 is used to drive the lifting inner cylinder 510 to move in the vertical direction. Clamping assemblies 600 are respectively disposed on the top surface of the lifting inner cylinder 510. The clamping assembly 600 includes a bearing platform 610, a clamping servo motor 620, a left arc-shaped pressure arm 630 and a right arc-shaped pressure arm 640. The clamping servo motor 620 is used to drive the left arc-shaped pressure arm 630 and the right arc-shaped pressure arm 640 to slide towards each other. The controller is connected to an external position sensor to obtain the positional deviation between the center of the front end of the pipe and the center of the target sleeve, and controls the transverse servo motor 420, the lifting servo motor 520 and the clamping servo motor 620 in real time accordingly. Please see Figure 1 The automated guided vehicle (AGV) chassis 100 is a mobile foundation used to support and move the front support base 200, the rear support base 300, and the tubing. This chassis can be electrically driven, and its top surface has an installation reference surface. The front support base 200 and the rear support base 300 are respectively fixedly connected to both ends of the top surface of the AGV chassis 100 along its length. The length direction refers to the direction in which the AGV chassis 100 and the tubing are basically aligned. This arrangement at both ends allows the ultra-long cylindrical tubing to be supported by two spaced support points, reducing localized stress concentration caused by single-point support. The fixed connection can be achieved by bolt connection, welding connection, or a combination of bolts and locating pins. The combination of bolts and locating pins ensures the stability of the fixed center distance between the front support base 200 and the rear support base 300. The transverse moving components 400 are respectively mounted on the front support base 200 and the rear support base 300. The transverse moving base plate 410 in the transverse moving component 400 is used to support the lifting component 500 and the clamping component 600 above it. The transverse moving servo motor 420 is used to output a controllable rotation angle and drive the transverse moving base plate 410 to move in the horizontal left and right directions. The horizontal left and right directions refer to the directions that are perpendicular to the pipe axis and parallel to the top surface of the automatic guided vehicle chassis 100. By setting lateral movement components 400 on the front bearing base 200 and the rear bearing base 300 respectively, the front and rear support points of the pipe can move in the same direction or move in opposite directions in the horizontal left and right directions, so that the center line of the pipe can be translated or yawed relative to the center line of the target casing. Compared with the method of adjusting the position by micro-motion of the entire automatic guided vehicle chassis 100, this structure separates the docking adjustment action from the chassis walking action, reducing the impact of ground friction differences and vehicle inertia on the centering accuracy. Lifting components 500 are respectively set on the top surface of the transverse base plate 410. The lifting inner cylinder 510 in the lifting component 500 is used to support the clamping component 600 above it. The lifting servo motor 520 is used to drive the lifting inner cylinder 510 to move in the vertical direction. The vertical direction refers to the height direction perpendicular to the top surface of the automatic guide vehicle chassis 100. The front and rear lifting components 500 can be lifted synchronously to adjust the overall height of the pipe, or they can be lifted in opposite directions to adjust the pitch attitude of the pipe. This setting makes the pipe height adjustment independent of external cranes or multi-axis robots, and is suitable for local precision docking before pipe threading. Clamping assemblies 600 are respectively disposed on the top surface of the lifting inner cylinder 510. The bearing platform 610 in the clamping assembly 600 is used to directly support the pipe. The left arc-shaped pressure arm 630 and the right arc-shaped pressure arm 640 are used to apply clamping constraints from both sides of the pipe. The arc-shaped inner surfaces of the left arc-shaped pressure arm 630 and the right arc-shaped pressure arm 640 form a surface contact engagement with the outer wall of the cylindrical pipe at a preset envelope angle. When the clamping servo motor 620 drives the two to slide towards each other, it can limit the radial rolling and lateral disengagement of the pipe on the bearing platform 610. The controller can be a programmable logic controller, an industrial control computer, or a motion controller with a servo drive communication interface. The controller is electrically or communicatively connected to the traverse servo motor 420, the lifting servo motor 520, and the clamping servo motor 620 to send position commands, speed commands, start / stop commands, and to collect servo motor current, position feedback, and alarm status. Through the above structural combination, the automatic guided vehicle can constrain the pipe by the clamping component 600 during long-distance transportation. After arriving at the pipe-threading processing station, the traverse component 400 and the lifting component 500 can complete the pipe posture adjustment, thereby reducing the probability of pipe rolling slippage and butt joint scratching.

[0019] The clamping assembly 600 also includes a worm gear reducer 650, a drive spur gear 660, a left rack 670, and a right rack 680; wherein, the output shaft of the clamping servo motor 620 is connected to the worm gear reducer 650, the output shaft of the worm gear reducer 650 is fixedly connected to the drive spur gear 660, the left and right sides of the drive spur gear 660 respectively mesh with the left rack 670 and the right rack 680, the outer end of the left rack 670 is vertically fixedly connected to the left arc-shaped pressure arm 630, and the outer end of the right rack 680 is vertically fixedly connected to the right arc-shaped pressure arm 640; The worm gear reducer 650 is a speed reduction transmission component formed by the meshing of a worm and a worm wheel. Its function in this device is not simply to reduce the speed, but to prevent the drive spur gear 660 from being driven in the opposite direction by the reaction force of the tube after the clamping servo motor 620 is de-energized. The reverse self-locking characteristic refers to the mechanical holding characteristic that makes it difficult to reverse the rotation of the input end when the output end is subjected to external torque. This characteristic allows the clamping position to be maintained under conditions without continuous power supply. The output shaft of the clamping servo motor 620 is connected to the worm gear reducer 650. The connection method can be key connection, shrink sleeve connection or coupling connection. The output shaft of the worm gear reducer 650 is fixedly connected to the drive spur gear 660. The left and right sides of the drive spur gear 660 mesh with the left rack 670 and the right rack 680 respectively. When the drive spur gear 660 rotates, the left rack 670 and the right rack 680 located on both sides of it move towards each other or away from each other because the meshing directions are opposite. The outer end of the left rack 670 is vertically fixed to the left arc-shaped pressure arm 630, and the outer end of the right rack 680 is vertically fixed to the right arc-shaped pressure arm 640. The vertical fixed connection can be achieved by welding, bolting, or integral machining. When the clamping servo motor 620 is running in the forward direction, the drive spur gear 660 causes the left rack 670 and right rack 680 to slide towards each other, causing the left arc-shaped pressure arm 630 and right arc-shaped pressure arm 640 to move closer to the center of the pipe. When the clamping servo motor 620 is running in the reverse direction, the left rack 670 and right rack 680 slide away from each other, causing the left arc-shaped pressure arm 630 and right arc-shaped pressure arm 640 to release the pipe. This transmission structure converts the rotational motion of the clamping servo motor 620 into the symmetrical linear motion of the left and right pressure arms. The clamping force on the pipe can be distributed on both sides of the pipe, reducing the pipe center offset caused by unilateral clamping. Compared with the unilateral pushing structure, the drive spur gear 660 drives the left rack 670 and the right rack 680 simultaneously, so that the stroke of the pressure arms on both sides has gear meshing constraint, which makes it easier to bring the clamping center close to the support center of the bearing platform 610. After clamping, the power supply of the clamping servo motor 620 is cut off, and the worm gear reducer 650 restricts the retraction of the left rack 670 and the right rack 680. During pipe transportation, there is no need to continuously output motor holding current, reducing the risk of loss of clamping force due to power failure or drive failure.

[0020] The transverse assembly 400 also includes a transverse guide rail 430 and a transverse ball screw 440; wherein, the top surface of the front bearing base 200 is slidably connected to the transverse base plate 410 through the transverse guide rail 430, the output shaft of the transverse servo motor 420 is connected to the transverse ball screw 440 through a plum blossom coupling 450, and the nut flange of the transverse ball screw 440 is fixed to the side wall of the transverse base plate 410. Please see Figure 2 The transverse guide rail 430 is a linear guide component used to limit the movement direction of the transverse base plate 410 and bear the load above the transverse base plate 410. The transverse ball screw 440 is a transmission component that converts the rotational motion of the transverse servo motor 420 into the linear motion of the transverse base plate 410. The top surface of the front bearing base 200 is slidably connected to the transverse base plate 410 through the transverse guide rail 430. The corresponding transverse component 400 on the rear bearing base 300 can adopt the same connection method. The transverse guide rail 430 can be configured as two, three or four parallel guide rails, preferably four transverse guide rails 430, to improve the anti-overturning capacity of the transverse base plate 410 when bearing ultra-long pipes; the transverse guide rail 430 and the front bearing base 200 can be fixed by countersunk bolts, and the bottom surface of the transverse base plate 410 is provided with a slider that cooperates with the transverse guide rail 430, and the slider slides linearly along the transverse guide rail 430; The output shaft of the transverse servo motor 420 is connected to the transverse ball screw 440 through a plum blossom coupling 450. The plum blossom coupling 450 can compensate for the coaxiality error between the output shaft of the transverse servo motor 420 and the transverse ball screw 440 within the assembly tolerance range, and reduce the jamming caused by the transmission of installation error to the screw pair. The nut flange of the transverse ball screw 440 is fixed to the side wall of the transverse base plate 410. The fixing method can be bolt connection. When the nut flange rotates with the screw and generates axial displacement, it drives the transverse base plate 410 to move along the transverse guide rail 430. The transverse servo motor 420 can be equipped with an absolute encoder or an incremental encoder. The controller reads the motor position feedback through the servo driver and controls the stroke of the transverse base plate 410 according to the set number of pulses or position command. Compared to ordinary trapezoidal screws, the transverse ball screw 440 reduces frictional resistance and backlash, making it suitable for millimeter-level or sub-millimeter-level lateral adjustment of the pipe centerline after the automated guided vehicle chassis 100 has stopped. The transverse guide rail 430 bears vertical loads and lateral forces, while the transverse ball screw 440 mainly undertakes driving and positioning functions. The division of labor between the two enables the transverse base plate 410 to maintain stable linear motion while carrying the pipe. When the front and rear lateral movement components 400 move synchronously in the opposite direction according to the controller instructions, a certain lateral difference is formed between the front and rear support points. This difference is used to change the yaw angle of the pipe in the horizontal plane, thus enabling the overall attitude adjustment of the vehicle body to be converted into linear adjustment of the two front and rear support points.

[0021] The lifting assembly 500 also includes a lifting housing 530, a vertical guide rail 540, and a lifting ball screw 550; wherein, the top surface of the transverse base plate 410 is fixedly connected to the lifting housing 530, the inner side wall of the lifting housing 530 is slidably connected to the lifting inner cylinder 510 through the vertical guide rail 540, the output shaft of the lifting servo motor 520 is connected to the lifting ball screw 550 through a cross slider coupling 560, and the nut flange of the lifting ball screw 550 is fixed to the bottom surface of the lifting inner cylinder 510; Please see Figure 3 The lifting housing 530 is a supporting housing fixed to the top surface of the transverse base plate 410, used to install the vertical guide rail 540 and accommodate the vertical movement space of the lifting inner cylinder 510; the lifting inner cylinder 510 is a lifting actuator that moves vertically and supports the carrying platform 610; the lifting housing 530 is fixedly connected to the top surface of the transverse base plate 410, and the fixed connection can be a bolt connection, a welding connection, or a combination of positioning pins and bolts; the inner wall of the lifting housing 530 is slidably connected to the lifting inner cylinder 510 through the vertical guide rail 540, which can be set to two, three, or four, preferably four vertical guide rails 540 arranged in different positions inside the lifting housing 530 to limit the swing of the lifting inner cylinder 510 when it moves vertically; The output shaft of the lifting servo motor 520 is connected to the lifting ball screw 550 via a cross-slider coupling 560. The cross-slider coupling 560 can compensate for the radial deviation between the output shaft of the lifting servo motor 520 and the lifting ball screw 550, which is suitable for reducing the degree of influence of off-center load on the screw when installed vertically. The nut flange of the lifting ball screw 550 is fixed to the bottom surface of the lifting inner cylinder 510. When the lifting servo motor 520 drives the lifting ball screw 550 to rotate, the nut flange drives the lifting inner cylinder 510 to move up and down along the vertical guide rail 540. The lifting ball screw 550 can be a ball screw with a preload structure to reduce axial clearance and enable the height command of the bearing platform 610 to be accurately converted into changes in the height of the pipe support point. The lifting assembly 500 limits the height adjustment of the support platform 610 to vertical linear motion. The vertical guide rail 540 provides guidance and anti-eccentric load support, and the lifting ball screw 550 provides position conversion and maintains rigidity. During pipe connection, the lifting assemblies 500 on the front support base 200 and the rear support base 300 can synchronously raise or lower the center height of the pipe. When the pitch angle needs to be adjusted, the controller causes the two sets of lifting servo motors 520 to move in opposite directions or with different displacements, so that a height difference is generated between the two support points of the pipe. Through this structure, the vertical attitude adjustment is achieved by the controllable stroke of the lifting inner cylinder 510, reducing the need for overall tilting of the automated guided vehicle chassis 100 or external hoisting equipment for height correction.

[0022] The top surface of the support platform 610 is machined with a V-shaped support groove 611; wherein, the left rack 670 and the right rack 680 are slidably connected to the top surface slide rail of the support platform 610 through dovetail grooves 612 respectively. Please see Figure 4 The V-shaped support groove 611 is an open-top groove structure formed by two intersecting inclined support surfaces, used to support cylindrical pipes of different outer diameters. The upward opening allows the pipe to be placed on the support platform 610 by external loading equipment or manual assistance. After the pipe falls into the V-shaped support groove 611, the outer circle of the pipe and the two inclined support surfaces form two contact areas, and the center of the pipe tends to be close to the center line of the V-shaped support groove 611. The included angle of the V-shaped support groove 611 can be determined according to the pipe diameter range, for example, it can be set to 90° to 120°. When the outer diameter of the pipe changes, the contact position of the pipe changes along the inclined support surface, but its center is still constrained by the groove structure and located near the center of the support platform 610. The left rack 670 and the right rack 680 are slidably connected to the top slide rail of the support platform 610 via dovetail grooves 612. The dovetail groove 612 is a guide groove with an inwardly tapered sidewall in cross-section. The left rack 670 and the right rack 680 are provided with sliding parts that match the dovetail groove 612. The sliding connection of the dovetail groove 612 allows the left rack 670 and the right rack 680 to move in a predetermined straight direction within the top slide rail of the support platform 610, while restricting them from disengaging upward from the slide rail. Since the left arc-shaped pressure arm 630 and the right arc-shaped pressure arm 640 will be subjected to the reaction force of the pipe when clamping the pipe, the dovetail groove 612 can withstand the upward turning torque and lateral force generated by the reaction force, reducing the possibility of the rack meshing surface disengaging. The V-shaped support groove 611 and the dovetail grooves 612 of the left rack 670 and right rack 680 are used in a directional fit to form two types of constraints: lower support and lateral restraint of the pipe. When the pipe is placed, the V-shaped support groove 611 provides initial positioning to prevent the pipe from rolling laterally before clamping. When clamping, the left rack 670 and right rack 680 move towards each other along the dovetail grooves 612, so that the left arc-shaped pressure arm 630 and right arc-shaped pressure arm 640 apply pressure to both sides of the pipe. This structure makes the clamping action have a repeatable motion trajectory, reduces the uneven clamping force caused by the rack tilting or deflection, and helps to maintain the relative position stability between the center line of the pipe and the center line of the bearing platform 610.

[0023] The concave surfaces of the left arc-shaped pressure arm 630 and the right arc-shaped pressure arm 640 are both fixedly connected to the polyurethane anti-slip pad 690 by countersunk screws; the thickness of the polyurethane anti-slip pad 690 is 20mm. The concave surface is the arc-shaped contact surface of the left arc-shaped pressure arm 630 and the right arc-shaped pressure arm 640 facing the outer wall of the pipe; the polyurethane anti-slip pad 690 is a contact pad layer made of polyurethane elastic material, used to increase the friction coefficient between the pressure arm and the outer wall of the pipe, and to buffer the local indentation of the clamping force on the outer wall of the pipe; the head of the countersunk screw is recessed into the countersunk hole of the polyurethane anti-slip pad 690 or the mounting hole of the pressure arm, so that the screw head does not protrude from the contact surface of the polyurethane anti-slip pad 690, reducing the risk of scratches caused by direct contact between the metal screw and the pipe; The polyurethane anti-slip pad 690 has a thickness of 20mm. This thickness allows the polyurethane anti-slip pad 690 to have compressible margin under clamping force, which can accommodate the outer diameter tolerance of the pipe, slight surface ovality, and processing errors of the bearing platform 610. If the pad is too thin, the risk of local hard contact increases; if the pad is too thick, the correspondence between the pressure arm displacement and the clamping force becomes unstable. The 20mm thickness can achieve a feasible fit between anti-slip contact and clamping stiffness. The polyurethane anti-slip pad 690 can be set as a single arc-shaped pad or formed by splicing multiple arc-shaped pads. The countersunk screws are arranged at intervals along the arc length to reduce local warping of the pad when subjected to shear force. During the operation of the automated guided vehicle, the pipe is subjected to starting and stopping inertia and lateral turning forces. After the polyurethane anti-slip pad 690 comes into contact with the outer wall of the pipe, the frictional force and the normal clamping force provided by the arc-shaped pressure arm jointly inhibit the axial slippage and radial rolling of the pipe. Since the hardness of polyurethane material is lower than that of the metal pressure arm, when it comes into direct contact with the pipe, it can reduce the probability of indentations and scratches on the surface coating or outer wall of the inner oil pipe. The countersunk screw fixing method facilitates the replacement of the polyurethane anti-slip pad 690 after wear, maintaining the anti-slip performance and maintenance convenience of the clamping assembly 600.

[0024] Example 2: The control method for the automatic guided vehicle carrying device for material transfer of inner-lined oil pipe with reduced diameter includes: S1. The operating current of the clamping servo motor 620 is acquired in real time, and it is determined whether the operating current reaches the preset clamping current threshold and continues for a preset time. If it reaches the threshold, the power supply of the clamping servo motor 620 is cut off. If it does not reach the threshold, the operating current of the clamping servo motor 620 is acquired. If the clamping current threshold is not reached within the preset timeout period, the controller outputs an alarm signal and stops the operation. S2. Using the centerline of the target sleeve as the docking reference axis, the spatial position deviation between the center of the front end face of the pipe and the center of the target sleeve is obtained through an external position sensor to perform attitude differential calculation, and the differential lateral travel and differential lifting travel are calculated. S3. Control the transverse servo motors 420 on the front bearing base 200 and the rear bearing base 300 to move synchronously in opposite directions according to the differential transverse stroke; S4. Control the lifting servo motors 520 on the front support base 200 and the rear support base 300 to move synchronously in opposite directions according to the differential lifting stroke; S5. During the tube-driving and propulsion stage, the holding current required by the lifting servo motor 520 on the front bearing base 200 to maintain the current height of the lifting inner cylinder 510 is obtained in real time. The vertical sinking amount is calculated based on the increment of the holding current and the lifting servo motor 520 is controlled to output a compensation stroke equal to the vertical sinking amount upward. Please see Figure 5 The control method is executed by a controller, which is connected to the clamping servo motor 620, the traverse servo motor 420 and the lifting servo motor 520 respectively, and reads the motor running current, holding current and current position through the servo driver; during the data flow and interaction, the controller and each servo driver are connected to an industrial Ethernet bus that supports real-time communication, such as an automation control real-time bus or a process fieldbus, with the communication cycle set to 1ms to 4ms. The servo driver encapsulates the torque and current components of the motor and the encoder position data in a periodic process data object and sends them to the controller in real time. After parsing the process data object, the controller sends the position command or speed command to the servo driver through the downlink channel. This communication mechanism ensures millisecond-level data interaction latency, matching the real-time requirements of the control algorithm; the operating current is the current value generated by the clamping servo motor 620 to overcome the load during the clamping action, and the holding current is the current value required by the lifting servo motor 520 to resist external load while maintaining the current height of the lifting inner cylinder 510; the spatial position deviation is the horizontal and vertical offset distance between the center of the front end face of the pipe and the center of the target sleeve, which can be obtained by a laser displacement sensor, a vision measurement device, a contact probe, or a measurement reference on the workstation and transmitted to the controller; In S1, after the pipe is placed on the support platform 610, the controller sends a clamping command to the clamping servo motor 620, which drives the left arc-shaped pressure arm 630 and the right arc-shaped pressure arm 640 to slide towards each other. The controller acquires the operating current of the clamping servo motor 620 in real time with a set sampling period, which can be set from 10ms to 100ms. The clamping current threshold is pre-calibrated based on the outer diameter of the pipe, the wall thickness of the pipe, the compression amount of the polyurethane anti-slip pad 690, and the required clamping force. When the operating current reaches the preset clamping current threshold and remains so for a preset time, it indicates that the pressure arm has made stable contact with the outer wall of the pipe and formed the set clamping force. The preset time can be 2 seconds, or it can be set to 1 to 3 seconds depending on the pipe specifications. When the judgment condition is met, the controller cuts off the power supply to the clamping servo motor 620 and locks the position of the pressure arm through the mechanical holding capability of the clamping component 600. When the judgment condition is not met, the controller continues to acquire the operating current and maintain the clamping action. At the same time, the controller starts timing. If the operating current still does not reach the clamping current threshold within the default timeout period, the controller outputs an alarm signal and stops the operation. The default timeout period is calibrated based on the rated speed and maximum clamping stroke of the clamping servo motor and can be set to 3 to 5 seconds. This step uses current changes to determine whether the clamping is in place, reducing the risk of overvoltage or undervoltage caused by relying solely on fixed stroke clamping. In the control logic, the clamping current threshold represents the load current boundary corresponding to the clamping servo motor 620 when the clamping component 600 reaches the target clamping force, and is not the motor protection current. The process of determining this threshold may include the following steps: first, select the specifications of the pipe to be transferred and the allowable surface indentation range; then, gradually increase the clamping output of the clamping servo motor 620 in the debugging state, and simultaneously record the operating current, the compression amount of the polyurethane anti-slip pad 690, and the anti-rolling state of the pipe on the bearing platform 610. When the pipe does not roll or laterally disengage under the test conditions corresponding to the preset start-stop acceleration and turning lateral force, and the pipe surface does not exceed the allowable indentation range, the stable operating current under this state is used as the clamping current threshold for the pipe of this specification and stored in the controller; the preset time is used to eliminate the interference of instantaneous current spikes on the clamping position judgment. Only when the operating current is continuously maintained above the threshold will the controller consider that the clamping force has been stably established and allow the execution of power-off mechanical locking. In S2, the automated guided vehicle chassis 100 stops moving and remains stationary. The controller acquires the spatial positional deviation between the center of the pipe's front end face and the center of the target sleeve, and performs attitude differential calculation on this deviation. Attitude differential calculation refers to treating the pipe as a rigid body, taking the centerline of the target sleeve as the reference axis, and calculating the relative displacement that should occur at the front bearing base 200 and the rear bearing base 300 based on the offset of the pipe's front end relative to the reference axis. This calculation process essentially constructs a geometric mapping model for spatial attitude adjustment, the purpose of which is to accurately calculate the independent displacement of each support point required to eliminate the deviation at the end of the pipe without moving the entire chassis. Logically, the solution model receives spatial position deviation and pipe size parameters as input. By separating the deviation components of the two orthogonal planes, horizontal and vertical, it calculates the correction amounts for yaw and pitch angles, and finally outputs differential lateral travel and differential lifting travel. Physically, the model represents the geometric kinematic relationship of a slender rigid body under two-point support conditions, which achieves precise and controllable offset of the end spatial coordinates by changing the relative positions of the two support points. The controller calculates the differential lateral travel and differential lifting travel, where the differential lateral travel is used for horizontal left-right adjustment and the differential lifting travel is used for vertical adjustment. The input data for attitude differential calculation includes the horizontal offset distance and vertical offset distance of the center of the front end face of the pipe, the total length of the pipe, and the fixed center distance between the front bearing base 200 and the rear bearing base 300. The controller first unifies the coordinate direction of the measured horizontal and vertical offset distances to correspond to the positive and negative running directions of the transverse servo motor 420 and the lifting servo motor 520. Then, it determines the deviation trend of the front end of the pipe relative to the center of the target sleeve in the horizontal and vertical planes, respectively. The deviation trend is converted into the relative lateral movement and relative lifting amount that should be formed between the front and rear support points. Finally, the above relative amounts are allocated as servo position commands for the front support base 200 and the rear support base 300 respectively. The output of the above process is the differential lateral movement and differential lifting stroke, which flow to S3 and S4 as the target displacement input of the servo motor. In S3, the controller controls the transverse servo motors 420 on the front support base 200 and the rear support base 300 to move synchronously in opposite directions according to the differential transverse stroke. The reverse synchronous movement means that the transverse base plate 410 at the front support base 200 and the transverse base plate 410 at the rear support base 300 move in opposite directions within the same control cycle, and the amount of movement of the two is related to the differential transverse stroke. This action causes the front and rear support points of the pipe to form a lateral displacement difference in the horizontal plane, thereby adjusting the yaw angle of the pipe and making the center line of the pipe move closer to the center line of the target casing. In S4, the controller controls the lifting servo motors 520 on the front support base 200 and the rear support base 300 to move synchronously in opposite directions according to the differential lifting stroke; the reverse synchronous lifting creates a height difference between the front and rear support points of the pipe, which is used to compensate for the vertical offset of the front end of the pipe relative to the center of the target sleeve, thereby completing the pitch angle alignment of the pipe in the vertical plane; S3 and S4 can be executed sequentially, or they can be executed in the same control cycle when the controller has multi-axis linkage control capability. During the execution, the controller continuously reads the position feedback of the transverse servo motor 420 and the lifting servo motor 520, and stops after reaching the set position; In S5, during the pipe-driving stage, the pipe gradually enters the target casing. Changes in the length of the suspended pipe section will cause the pipe's center of gravity to shift and its deflection to change. The controller obtains in real time the holding current required by the lifting servo motor 520 on the front bearing base 200 to maintain the current height of the lifting inner cylinder 510, and compares this holding current with the reference value corresponding to the benchmark holding current or the no-load running current to obtain the increment of the holding current. The controller calculates the vertical sinking amount based on the increment of the holding current and controls the lifting servo motor 520 to output a compensation stroke equal to the vertical sinking amount. Through this method, the current feedback of the lifting servo motor 520 is not only used for motor protection, but also used as a measurement of the change in the force on the pipe to participate in the height compensation calculation, so that the vertical deviation between the center of the front end of the pipe and the center of the target sleeve can be continuously corrected during the pipe pushing process. In the control system, the increment of the holding current represents the change in the additional load applied to the lifting assembly 500 of the front bearing base 200 due to changes in the pipe's propulsion, cantilever, or stress state. The process of obtaining it is as follows: the controller records the reference holding current after alignment before pipe propulsion; during pipe propulsion, the current holding current is read according to the sampling period; the current holding current is compared with the reference holding current to obtain the current increase. When the increase exceeds the preset trigger boundary, the controller calls the stiffness conversion coefficient corresponding to the elastic modulus of the pipe material to convert the current increase into the vertical sinking of the pipe front end. The physical meaning of the vertical sinking is the estimated displacement of the center of the pipe front end relative to the centering reference axis downward. This estimated displacement is used as the upward compensation stroke input of the lifting servo motor 520 to trigger the lifting action of the inner cylinder 510 of the front bearing base 200.

[0025] Step S2 includes: determining the differential lateral travel and differential lifting travel based on the horizontal offset distance, vertical offset distance, longitudinal distance from the center of the front end face of the pipe to the preset deflection rotation center, and the fixed center distance between the front bearing base 200 and the rear bearing base 300 in the spatial position deviation. The attitude differential calculation in step S2 uses the longitudinal distance from the center of the front end face of the pipe to the preset deflection rotation center, the fixed center distance between the front bearing base 200 and the rear bearing base 300, the horizontal offset distance, and the vertical offset distance as input parameters; the total length of the pipe is the axial length of the pipe from the rear end to the front end, which can be entered by the production management system, read by barcode information, or manually input into the controller. The longitudinal distance from the center of the front end face of the pipe to the preset deflection rotation center refers to the axial distance between the center of the front end face of the pipe and the actual rotation center that acts as a fulcrum when the pipe is adjusting its attitude deflection. For example, when the front and rear bearing bases move synchronously in opposite directions, the deflection rotation center is located at the midpoint of the line connecting the front and rear support points. This longitudinal distance is equal to the sum of the overhang length of the front end of the pipe and half of the fixed center distance. The fixed center distance is the distance between the support centers of the front bearing base 200 and the rear bearing base 300. This distance is measured and stored in the controller during the installation and commissioning of the device. The horizontal offset distance is the distance between the center of the front end face of the pipe and the center of the target sleeve in the horizontal left and right direction. The vertical offset distance is the distance between the center of the front end face of the pipe and the center of the target sleeve in the vertical direction. The controller divides the horizontal offset distance in the spatial position deviation by the longitudinal distance from the center of the pipe's front end face to the preset deflection rotation center to obtain the yaw angle tangent value. This calculation is based on the geometric relationship that the pipe is regarded as a rigid body. The ratio of the horizontal offset distance to the longitudinal distance corresponds to the tangent value of the angle of the pipe's centerline relative to the reference axis in the horizontal plane. Because in actual pipe laying conditions, the horizontal offset distance of the pipe is much smaller than the total length of the pipe, the small angle approximation principle can be reasonably used to treat the small deflection of the pipe around the rear support point or center of gravity as a linear relationship. To avoid abnormal divisor, the controller determines whether the total length of the pipe is greater than the preset minimum length before calculation. The preset minimum length can be set to 1m. If the total length of the pipe does not reach this value, the controller stops the differential calculation and outputs a parameter abnormality signal. The controller multiplies the yaw angle tangent by the fixed center distance between the front support base 200 and the rear support base 300 on the automated guided vehicle chassis 100 to obtain the differential lateral travel. The differential lateral travel represents the horizontal relative displacement that needs to be formed between the two support points. The rationality of this calculation principle is that it simplifies the complex spatial angle adjustment into a linear proportional translation between the two support points. Because it adopts the geometric relationship of linear mapping, it can quickly and accurately convert the measurement deviation into the linear drive command of the servo motor, avoiding the control delay caused by complex trigonometric function calculations. If the horizontal offset distance is positive, the controller moves the transverse base plates 410 of the front bearing base 200 and the rear bearing base 300 in opposite directions according to the preset coordinate direction; if the horizontal offset distance is negative, the transverse direction is opposite; in order to avoid excessive changes in the center position of the pipe, the controller can allocate the differential transverse stroke to the front support point and the rear support point to move in opposite directions by half of the differential transverse stroke, or it can use unequal proportions according to the load distribution of the front and rear support points, but the relative displacement of the two remains equal to the calculated differential transverse stroke; The controller divides the vertical offset distance in the spatial position deviation by the longitudinal distance to obtain the pitch angle tangent value; when the vertical offset distance is positive or negative, it indicates that the center of the front end face of the pipe is higher or lower than the center of the target sleeve, respectively. The controller determines the moving direction of the front and rear lifting components 500 accordingly. The controller multiplies the pitch angle tangent by the fixed center distance to obtain the differential lifting stroke; the differential lifting stroke indicates the height difference that needs to be formed between the front and rear support points; the controller can raise the front support base 200 by half of the differential lifting stroke and lower the rear support base 300 by half of the differential lifting stroke, or it can keep one support base stationary while the other support base moves for the entire differential lifting stroke. The specific allocation is limited by the lifting stroke margin and the stability of the pipe support; Based on the above calculations, the yaw and pitch angles of the pipe do not need to be achieved by the overall steering or reciprocating micro-movement of the Automated Guided Vehicle chassis 100, but are converted into the lateral and lifting strokes of the two load points at the front and rear. This calculation only relies on the measurable length and offset distance, and the controller can directly convert the measurement data into servo motor position commands, reducing the number of repeated trial and adjustment. To clearly present the above attitude differential calculation logic, a quantitative derivation example is provided here: Assume that the longitudinal distance from the center of the front end face of the pipe to the preset deflection rotation center is 10000mm, and the fixed center distance between the front bearing base 200 and the rear bearing base 300 is 6000mm; the sensor measures that the horizontal offset distance of the center of the front end face of the pipe relative to the center of the target sleeve is 20mm, and the vertical offset distance is -15mm; In S201, the controller calculates the yaw angle tangent as 20 divided by 10000, which equals 0.002; the controller calculates the differential lateral travel as 0.002 multiplied by 6000, which equals 12mm; this means that the front and rear support points need to form a horizontal relative displacement of 12mm, and the controller can allocate the front bearing base 200 to move 6mm to the left and the rear bearing base 300 to move 6mm to the right; similarly, the pitch angle tangent is -15 divided by 10000, which equals -0.0015; The differential lifting stroke is -0.0015 multiplied by 6000, which equals -9mm; the controller can allocate the front bearing base 200 to rise by 4.5mm and the rear bearing base 300 to fall by 4.5mm; through the above structured decomposition and quantitative calculation, the mapping relationship between the algorithm's input, processing logic and output instructions is clear, and accurate attitude correction can be achieved without complex nonlinear calculations.

[0026] Step S5 includes: S501, obtaining the reference current of the lifting component 500 when there is no pipe load as the no-load operating current, and determining whether the increment of the holding current exceeds 10% of the no-load operating current; S502. If the limit is exceeded, the vertical sinking of the pipe under the current stress state is determined based on the increment of the holding current, and the lifting servo motor 520 is controlled to output a compensation stroke equal to the vertical sinking; if the limit is not exceeded, the holding current is continued to be acquired. In step S5, the controller acquires the holding current of the lifting servo motor 520 on the front bearing base 200 with a set sampling period. The sampling period can be set to 10ms to 200ms. The increment of the holding current is the difference between the current holding current and the reference holding current. The reference holding current can be recorded before the pipe is pushed through, when the pipe is aligned and the overhang length is within the preset range, or it can be calibrated by combining the current reference of the lifting assembly 500 when it is running unloaded with the static support load of the pipe. The unloaded operating current is the current value required for the lifting assembly 500 to maintain or run at low speed under no pipe load or standard unload conditions, and is used to establish the current change judgment threshold. In S501, the controller determines whether the increment of the holding current exceeds 10% of the no-load operating current; 10% is used as a trigger threshold to distinguish between servo drive measurement fluctuations, lead screw friction changes, and increased stress caused by pipe deflection; if the increment of the holding current does not exceed the threshold, the controller determines that the current pipe subsidence has not reached the level that needs compensation and continues to acquire the holding current; if the increment of the holding current exceeds the threshold, the controller enters the compensation calculation. In S502, the controller multiplies the increment of the current by a stiffness conversion factor calibrated based on the elastic modulus of the pipe material to obtain the vertical settlement of the pipe under the current stress state. The stiffness conversion factor is a calibration parameter that converts the current increment into the vertical displacement, and its unit can be expressed as mm / A. Here, a pipe deflection estimation model based on motor current is actually established. The purpose of this model is to indirectly calculate the deflection through the current feedback of the driver when the settlement of the suspended end of the pipe cannot be directly measured. In terms of physical relationships, this model characterizes the pipe as a dynamically changing cantilever beam during the advancement process. The increase in cantilever length leads to an increase in the additional load on the front bearing base 200, and the lifting servo motor 520 must increase the holding current to resist this additional load. At the same time, the vertical sinking of the pipe due to its own weight has a specific mechanical proportional relationship with the elastic modulus of the material and the stress state. Because the increment of the holding current is positively correlated with the additional load, and there is a definite conversion relationship between the additional load and the pipe deflection within the elastic range, the electrical parameters can be accurately converted into mechanical deformation through the pre-calibrated stiffness conversion coefficient. This coefficient can be obtained through experimental calibration. During calibration, pipes of the same material or with the same elastic modulus range as the production pipes are selected. The pipes are placed on the device, and the overhang length is gradually increased or a known vertical load is applied. At the same time, the holding current increment of the lifting servo motor 520 on the front bearing base 200 and the vertical sinking of the front end of the pipe are recorded. The recorded data are fitted to obtain the proportional relationship between the current increment and the vertical sinking, and the proportional coefficient is stored in the controller. For pipes with different elastic moduli, the controller can call the corresponding stiffness conversion coefficient. After obtaining the vertical sinking amount, the controller sends an upward compensation position command to the lifting servo motor 520 on the forward bearing base 200. The compensation stroke is equal to the calculated vertical sinking amount. The lifting servo motor 520 drives the lifting inner cylinder 510 to move upward, and the bearing platform 610 drives the front support point of the pipe to move upward, so that the center of the front end of the pipe is raised and coincides with the reference axis or enters the preset centering tolerance range. The compensation action can be set with a maximum single compensation stroke and a maximum compensation speed. For example, the single compensation stroke can not exceed 5mm and the compensation speed can not exceed 20mm / s to reduce the impact contact between the pipe and the target sleeve. After compensation is completed, the controller continues to acquire the holding current and repeat the judgment so that the deflection change during the tube pushing can be continuously corrected by the lifting component 500. To further clarify the algorithm implementation of the deflection estimation model, a quantitative derivation example of calibration and conversion is provided here: In the calibration stage, a predetermined high-strength steel-grade inner-lined oil pipe with an outer diameter of 73mm is selected, and a known downward displacement is applied to the suspended end of the pipe. For example, for every 1mm of downward pressure, the holding current of the lifting servo motor 520 of the front bearing base 200 is recorded to increase by 0.2A. Through linear fitting, the stiffness conversion factor of this specification of pipe was determined to be 5mm / A. In the actual control of the pipe pushing stage, if the reference holding current recorded by the controller when the alignment is completed is 3.0A, and the current holding current read at a certain moment during the pushing process reaches 3.5A, and the no-load operating current is 1.0A, the controller judges that the increase in holding current exceeds 10% of the no-load operating current, thus meeting the triggering condition. The controller multiplies the current increment of 0.5A by the stiffness conversion factor of 5mm / A, and calculates that the vertical settlement of the pipe at this time is 2.5mm. The controller sends a position compensation command to the lifting servo motor 520 of the forward bearing base 200 to move upward by 2.5mm. The above example shows in detail the rule flow of the conversion of the underlying electrical parameters into mechanical deformation, making the compensation algorithm logically transparent and fully programmable.

[0027] The clamping assembly 600 includes a worm gear reducer 650, a left rack 670, and a right rack 680; the specific steps of cutting off the power supply to the clamping servo motor 620 in step S1 include: after cutting off the power supply to the clamping servo motor 620, mechanically locking the positions of the left rack 670 and the right rack 680. The clamping servo motor 620 is driven by a worm gear reducer 650 through a rack and pinion transmission, causing the left rack 670 and right rack 680 to drive the left arc-shaped pressure arm 630 and right arc-shaped pressure arm 640 to slide towards each other. In step S1, the controller determines whether the pipe has been fully clamped based on the operating current of the clamping servo motor 620. Fully clamped means that the left arc-shaped pressure arm 630 and right arc-shaped pressure arm 640 have made stable contact with the outer wall of the pipe through the polyurethane anti-slip pad 690, and the operating current of the clamping servo motor 620 reaches the preset clamping current threshold and continues for a preset time. The preset time can be 2 seconds, or it can be set to 1 to 3 seconds depending on the outer diameter of the pipe and the clamping response time. After determining that the pipe has been fully clamped, the controller cuts off the power to the clamping servo motor 620. The power cut-off can be achieved by enabling and disabling the servo driver, disconnecting the contactor, or stopping the power output. After the power is cut off, the clamping servo motor 620 no longer relies on continuous current to maintain torque. At this time, the reverse self-locking characteristic of the worm gear reducer 650 restricts its output shaft from rotating in the opposite direction under the action of external reaction force. The drive spur gear 660 cannot be pushed back by the left rack 670 and the right rack 680, and the positions of the left rack 670 and the right rack 680 are mechanically locked. Mechanical locking means that the rack position is maintained by the self-locking action of the transmission pair of the worm gear reducer 650, rather than by the continuous power supply of the clamping servo motor 620. After the positions of the left rack 670 and the right rack 680 are locked, the left arc-shaped pressure arm 630 and the right arc-shaped pressure arm 640 maintain the clamping state of the tube; the radial rolling degree of freedom of the tube during the movement of the automated guided vehicle is eliminated. The radial rolling degree of freedom refers to the possibility of the cylindrical tube rolling laterally around its own axis or along the bearing platform 610; since the clamping force is still maintained by the worm gear reducer 650 when the power is off, the tube does not need to rely on the continuous output torque of the motor to maintain clamping when the automated guided vehicle stops, starts or turns. This method combines current feedback to determine the clamping position with mechanical holding by the worm gear, so that the clamping force formation process and the clamping position holding process are respectively handled by the electronic control judgment and the mechanical structure, reducing the continuous power supply requirement during long-distance circulation and improving the reliability of pipe holding under power failure conditions.

[0028] This application has been described through the above embodiments; however, it should be understood that the above embodiments are for illustrative purposes only and are not intended to limit this application to the described embodiments. Those skilled in the art will understand that many more variations and modifications can be made based on the teachings of this application, and all such variations and modifications fall within the scope of protection claimed in this application.

Claims

1. An automatic guided vehicle carrying device for material transfer using a reduced-diameter inner-lined oil pipe, characterized in that, include: Automated guided vehicle chassis (100); The front support base (200) and the rear support base (300) are respectively fixedly connected to the two ends of the top surface of the automated guided vehicle chassis (100) in the length direction; A transverse component (400) is respectively disposed on the front support base (200) and the rear support base (300), wherein the transverse component (400) includes a transverse base plate (410) and a transverse servo motor (420), and the transverse servo motor (420) is used to drive the transverse base plate (410) to move in the horizontal left and right directions; Lifting components (500) are respectively disposed on the top surface of the transverse base plate (410). The lifting components (500) include a lifting inner cylinder (510) and a lifting servo motor (520). The lifting servo motor (520) is used to drive the lifting inner cylinder (510) to move in the vertical direction. Clamping assemblies (600) are respectively disposed on the top surface of the lifting inner cylinder (510). The clamping assembly (600) includes a bearing platform (610), a clamping servo motor (620), a left arc-shaped pressure arm (630), and a right arc-shaped pressure arm (640). The clamping servo motor (620) is used to drive the left arc-shaped pressure arm (630) and the right arc-shaped pressure arm (640) to slide towards each other. The controller is connected to an external position sensor to obtain the positional deviation between the center of the front end face of the pipe and the center of the target sleeve, and controls the transverse servo motor (420), the lifting servo motor (520) and the clamping servo motor (620) in real time accordingly.

2. The automatic guided vehicle carrying device for material transfer of inner-lined oil pipe with reduced diameter as described in claim 1, characterized in that, The clamping assembly (600) further includes a worm gear reducer (650), a drive spur gear (660), a left rack (670), and a right rack (680); wherein, the output shaft of the clamping servo motor (620) is connected to the worm gear reducer (650), the output shaft of the worm gear reducer (650) is fixedly connected to the drive spur gear (660), the left and right sides of the drive spur gear (660) respectively mesh with the left rack (670) and the right rack (680), the outer end of the left rack (670) is vertically fixedly connected to the left arc-shaped pressure arm (630), and the outer end of the right rack (680) is vertically fixedly connected to the right arc-shaped pressure arm (640).

3. The automatic guided vehicle carrying device for material transfer of inner-lined oil pipe with reduced diameter as described in claim 2, characterized in that, The transverse assembly (400) further includes a transverse guide rail (430) and a transverse ball screw (440); wherein, the top surface of the front bearing base (200) is slidably connected to the transverse base plate (410) through the transverse guide rail (430), the output shaft of the transverse servo motor (420) is connected to the transverse ball screw (440) through a plum blossom coupling (450), and the nut flange of the transverse ball screw (440) is fixed to the side wall of the transverse base plate (410).

4. The automatic guided vehicle carrying device for material transfer of inner-lined oil pipe with reduced diameter as described in claim 3, characterized in that, The lifting assembly (500) also includes a lifting housing (530), a vertical guide rail (540), and a lifting ball screw (550); wherein, the top surface of the transverse base plate (410) is fixedly connected to the lifting housing (530), the inner wall of the lifting housing (530) is slidably connected to the lifting inner cylinder (510) through the vertical guide rail (540), the output shaft of the lifting servo motor (520) is connected to the lifting ball screw (550) through a cross slider coupling (560), and the nut flange of the lifting ball screw (550) is fixed to the bottom surface of the lifting inner cylinder (510).

5. The automatic guided vehicle carrying device for material transfer of inner-lined oil pipe with reduced diameter as described in claim 4, characterized in that, The top surface of the support platform (610) is machined with a V-shaped support groove (611); wherein the left rack (670) and the right rack (680) are slidably connected to the top surface slide of the support platform (610) through dovetail grooves (612).

6. The automatic guided vehicle carrying device for material transfer of inner-lined oil pipe with reduced diameter as described in claim 5, characterized in that, The concave surfaces of the left arc-shaped pressure arm (630) and the right arc-shaped pressure arm (640) are both fixedly connected to the polyurethane anti-slip pad (690) by countersunk screws; wherein, the thickness of the polyurethane anti-slip pad (690) is 20mm.

7. A control method, applied to the automatic guided vehicle carrying device for material transfer of inner-lined oil pipe with reduced diameter as described in claim 1, characterized in that, include: S1. Real-time acquisition of the operating current of the clamping servo motor (620), determination of whether the operating current reaches the preset clamping current threshold and continued for a preset time. If the condition is met, the power supply to the clamping servo motor (620) is cut off. If the threshold is not reached, the operating current of the clamping servo motor (620) will continue to be acquired. If the clamping current threshold is not reached within the preset timeout period, the controller will output an alarm signal to stop the operation. S2. Using the centerline of the target sleeve as the docking reference axis, the spatial position deviation between the center of the front end face of the pipe and the center of the target sleeve is obtained through an external position sensor to perform attitude differential calculation, and the differential lateral travel and differential lifting travel are calculated. S3. Control the transverse servo motors (420) on the front bearing base (200) and the rear bearing base (300) to move synchronously in opposite directions according to the differential transverse stroke; S4. Control the lifting servo motors (520) on the front support base (200) and the rear support base (300) to move synchronously in opposite directions according to the differential lifting stroke; S5. During the tube-driving stage, the holding current required by the lifting servo motor (520) on the front bearing base (200) to maintain the current height of the lifting inner cylinder (510) is obtained in real time. The vertical sinking amount is calculated based on the increment of the holding current and the lifting servo motor (520) is controlled to output a compensation stroke equal to the vertical sinking amount upward.

8. The control method according to claim 7, characterized in that, Step S2 includes: determining the differential lateral travel and the differential lifting travel based on the horizontal offset distance, vertical offset distance, longitudinal distance from the center of the front end face of the pipe to the preset deflection rotation center, and the fixed center distance between the front bearing base (200) and the rear bearing base (300) in the spatial position deviation.

9. The control method according to claim 7, characterized in that, Step S5 includes: S501. Obtain the reference current of the lifting assembly (500) when there is no pipe load as the no-load operating current, and determine whether the increment of the holding current exceeds 10% of the no-load operating current; S502. If it exceeds, determine the vertical sinking amount of the pipe under the current stress state according to the increment of the holding current, and control the lifting servo motor (520) to output a compensation stroke equal to the vertical sinking amount; if it does not exceed, continue to obtain the holding current.

10. The control method according to claim 7, characterized in that, The clamping assembly (600) includes a worm gear reducer (650), a left rack (670), and a right rack (680); the specific steps of cutting off the power supply of the clamping servo motor (620) in step S1 include: after cutting off the power supply of the clamping servo motor (620), mechanically locking the positions of the left rack (670) and the right rack (680).

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