A rigid-flexible composite connecting device and switching method for a multi-section pipe robot

Abstract

The application discloses a kind of rigid-flexible composite connecting devices for multi-section pipeline robot, comprising: connecting component I and connecting component II;Connecting component I includes mounting seat I, cable assembly and butt joint ball rod;Connecting component II includes mounting seat II, ball head guide assembly and ball head limiting assembly;One end of cable assembly is connected with mounting seat I, the other end is connected with mounting seat II;Ball head guide assembly and ball head limiting assembly are arranged on mounting seat II;One end of butt joint ball rod is connected with mounting seat I, the other end is provided with ball head, ball head guide assembly is provided with the guide channel along the axial direction in, ball head can enter and exit ball head limiting assembly along guide channel;The present application can realize rigid-flexible switching connection, with autonomous docking function, pipeline adaptive ability is strong, the overbending problem of multi-section pipeline robot is converted into the overbending problem of single-section pipeline robot, can pass through small curvature radius narrow bend and T type pipeline, improve the overbending of multi-section robot.

Description

Technical Field

[0001] This invention belongs to the field of pipeline robot technology, specifically relating to a rigid-flexible composite connection device and switching method for multi-section pipeline robots. Background Technology

[0002] Pipeline robots are used for pipeline condition assessment, leak detection, and fluid quality monitoring. Existing pipeline robots can be classified into three types based on their connection devices: connectionless, rigid connection, and flexible connection.

[0003] Connected pipe robots operate in single-section configurations. See appendix. Figure 1 For example, the peristaltic pipeline robot (Zhang Yanheng, Pang Zenghui. Design of a peristaltic pipeline robot [J]. Mechanical Design and Manufacturing, 2010(04):13-15.). The problem with the connectionless pipeline robot is that the driving capability of the connectionless robot is limited, which greatly restricts the pipeline robot's passage in complex three-dimensional pipelines. It cannot pass through complex three-dimensional pipeline networks containing T-shaped pipes, and is generally used in single pipes or straight pipes, with a narrow application range.

[0004] Rigidly connected pipe robots operate in multi-section configurations, each with its own drive unit. Rigid connections maintain a certain degree of freedom while constraining the movement of each section. They generally employ either passive or active robotic arm designs, such as universal joints or articulations. For example, patent publication number CN113483193A discloses a passive rigid connection device I; see appendix. Figure 2 It employs a universal joint connection method; Patent publication number CN107084297A discloses a passive rigid connection device II, see appendix. Figure 3 The ball joint is used for connection. The journal "Structural Design and Development of a Snake Robot" (Xiao Tingting, Liu Mingzhe, Liu Bingqi, et al. Structural Design and Development of a Snake Robot [J]. Measurement and Control Technology, 2016, 35(06):75-78.) discloses a snake-shaped pipeline robot; see appendix. Figure 4 It adopts an active robotic arm connection method.

[0005] The flexible connecting pipe robot operates in a multi-section configuration, each section having its own drive unit. Flexible

[0006] The connection is typically made of springs or other flexible materials, allowing it to adapt to changes in the pipe's orientation. For example, a flexible connection device is disclosed in the paper "Research on Small Pipeline Robot Systems" (Zhou Honglong. Research on Small Pipeline Robot Systems [D]. Jilin University, 2011). See appendix.Figure 6 , adopt spring.

[0007] In the patent with application number 202310887622.X, a kind of high compression ratio variable diameter mechanism, pipeline robot and linear variable diameter method, a kind of pipeline robot is disclosed, the axial size of the pipeline robot is small, pass through nature excellent, can be set according to different division multiple, respectively drive section and function section, drive section and function section can be randomly reconfigured by connecting device, so as to have different load capacity.

[0008] When the connecting device of the multi-section robot adopts the existing passive rigid connecting device, it does not have the function of active control, and the interaction between the sections is serious when the robot enters and exits the small curvature radius narrow bend and T type pipeline, which leads to poor passability;See Figure 5 , cannot be applied to complex pipe network systems containing T type pipe, L type pipe and other cross interfaces;

[0009] When the connecting device of the multi-section robot adopts the existing active rigid connecting device, the mechanical arm with multiple degrees of freedom needs to be actively controlled to make the robot pass through the complex pipe network structure, which has no self-adaptive ability, the passability is limited, and at the same time makes the control of the mechanical arm very complex.

[0010] When the connecting device of the multi-section robot adopts the existing flexible connecting device, the flexible connecting device does not have the function of active control;The multi-section pipeline robot will interfere when passing through the bend, and still cannot pass through the complex pipe network system containing T type pipe, L type pipe and other cross interfaces.

[0011] In summary, for the existing flexible connecting device and rigid connecting device, it is difficult to adapt to the high passability in the complex pipe network, and the connection operation can only be completed manually, lacking the automatic docking and separation function between modules, so that it is impossible to complete the complex tasks such as self-release of load in the pipeline, self-reconstruction of multiple modules. SUMMARY

[0012] Therefore, the present application provides a rigid-flexible composite connecting device for a multi-section pipeline robot and

[0013] Switching method, which can realize rigid-flexible switching connection, has the function of automatic docking, the pipeline adaptive ability

[0014] Strong, the bending problem of multi-section pipeline robot is converted into the bending problem of single-section pipeline robot, which can pass through the small curvature radius narrow bend and T type pipeline, and improves the bending performance of multi-section robot.

[0015] The present application is realized by the following technical solutions:

[0016] A rigid-flexible composite connecting device for a pipeline robot, used for connecting multiple sections of a pipeline robot, at least one of which is a driving section;

[0017] The rigid-flexible composite connecting device comprises a connecting assembly I and a connecting assembly II;

[0018] The connecting assembly I comprises a mounting seat I, a cable assembly and a ball rod;

[0019] The connecting assembly II comprises a mounting seat II, a ball head guide assembly and a ball head limiting assembly;

[0020] The mounting seat I is fixedly arranged on one section of the pipeline robot, and the mounting seat II is fixedly arranged on an adjacent section of the pipeline robot;

[0021] One end of the cable assembly is connected to the mounting seat I, and the other end is connected to the mounting seat II; the cable in the cable assembly can be retracted or extended according to the distance between the connecting assembly I and the connecting assembly II;

[0022] The ball head guide assembly is arranged on the mounting seat II, and an axial guide channel is arranged in the ball head guide assembly; the ball head limiting assembly is arranged on the mounting seat II and located between the guide channel and the mounting seat II; one end of the ball rod is connected to the mounting seat I, and the other end is provided with a ball head; the ball head can enter and exit the ball head limiting assembly along the guide channel, and the ball head limiting assembly is used for limiting or releasing the limitation of the ball head;

[0023] When the two sections of the pipeline robot are rigidly connected, the ball head limiting assembly limits the ball head; when the two sections of the pipeline robot are flexibly connected, the two sections of the pipeline robot are connected through the cable assembly.

[0024] Further, the cable assembly comprises three or more pull boxes, a retractable cable is wound in the pull box, and the pull box can provide a recovery force for the cable; the outlets of the cables on the pull boxes are distributed along the circumference;

[0025] Three or more movable pulleys are arranged on the mounting seat II, and the movable pulleys are in one-to-one correspondence with the outlets of the cables on the pull boxes in the rigid connection, and one end of each cable is wound around the corresponding movable pulley and fixedly connected to the mounting seat I;

[0026] The same number of guide wheels as the pull boxes are arranged on the mounting seat I, and the guide wheels are arranged at the outlets of the cables on the pull boxes to guide the cables.

[0027] Further, the number of pull boxes is four; the outlets of the cables of the pull boxes are evenly arranged along the circumference of the mounting seat I.

[0028] Evenly arranged.

[0029] Further, the ball head guide assembly is more than three guide claws; all the guide claws are arranged on the mounting seat II and are arranged along the circumference, each guide claw is a "T" shaped plate structure including a horizontal plate I and a vertical plate I,

[0030] Let the two ends of the horizontal plate I be the left end and the right end respectively, and let the central axis of the mounting seat II be the axis II;

[0031] The right end of the horizontal plate I is connected with the outer edge of the mounting seat I through a torsion spring pin, and the vertical plate I of the guide claw is arranged towards the axis II; the end face of the vertical plate I is arc-shaped; the guide channel is the space surrounded by the end faces of the vertical plates I of all the guide claws.

[0032] Further, the arc-shaped end face of the vertical plate I of each guide claw includes, from left to right, a capturing face, a transition face I, a working face and a transition face II,

[0033] connected in sequence.

[0034] The acute angle between the capturing face and the axis II is α, the acute angle between the transition face I and the axis II is β, and β < α; the working face is parallel to the axis II; the acute angle between the transition face II and the axis II is γ, and γ < α.

[0035] Further, the butt joint rod further includes a sleeve, a butt joint rod and a spring; one end of the sleeve is fixedly connected with the mounting seat I, and the other end is provided with a through hole I; one end of the butt joint rod is coaxially located in the sleeve through the through hole I, and the other end is connected with the ball head; the end of the butt joint rod located in the sleeve is provided with a coaxial annular edge, the spring is located in the sleeve and is sleeved outside the butt joint rod, one end of the spring abuts against the edge of the butt joint rod, and the other end abuts against the end where the through hole I of the sleeve is located.

[0036] Further, the left end of the horizontal plate I of each guide claw is provided with a clamping jaw, the mounting seat I is provided with a coaxial annular flange, and all the clamping jaws of the guide claws can be connected with the flange in cooperation;

[0037] In the process of switching the rigid connection, the distance between the two pipeline robots is reduced, when the ball head abuts against the end face of the vertical plate I of the guide claw after entering the guide channel, the guide claw is opened under the action of the ball head, so that the diameter of the circumscribed circle of the inner edges of all the clamping jaws arranged along the circumference is greater than the outer diameter of the flange;

[0038] When the ball head passes through the guide channel, the guide claw is reset under the action of the torsion spring, the clamping jaw abuts against the outer circumference of the mounting seat I, and the distance between the two pipeline robots is increased, so that the clamping jaw cooperates with the flange;

[0039] When the ball head is separated from the connecting assembly II, the ball head limiting assembly releases the limitation of the ball head, the ball head enters the guide channel under the elastic force of the spring, when the ball head abuts against the end face of the vertical plate I of the guide claw, the guide claw is opened under the action of the ball head, so that the diameter of the circumscribed circle of the inner edges of all the claws arranged along the circumference is greater than the outer diameter of the flange; increasing the distance between the two pipeline robots, the claws and the flange are separated, and the ball head and the guide channel are separated, and the rigid connection between the two pipeline robots is released, and the flexible connection is switched.

[0040] The claws are opened under the action of the ball head, so that the diameter of the circumscribed circle of the inner edges of all the claws arranged along the circumference is greater than the outer diameter of the flange; increasing the distance between the two pipeline robots, the claws and the flange are separated, and the ball head and the guide channel are separated, and the rigid connection between the two pipeline robots is released, and the flexible connection is switched.

[0041] Further, let any point on the mating surface of the claw and the flange be point A, the orthogonal projection of point A on the axis II be point a; any left end point of the working surface be point E, the orthogonal projection of point E on the axis II be point e; any point on the axial center line of the working surface be point F, the orthogonal projection of point F on the axis II be point f; any right end point of the working surface be point G, the orthogonal projection of point G on the axis II be point g; any point on the axis of the pin joint hole of the mounting seat II be point J, the orthogonal projection of point J on the axis II be point j;

[0042] Let the central axis of the mounting seat I be axis I, any point on the mating surface of the claw and the flange be point B, the orthogonal projection of point B on the axis I be point b; any point on the inner bottom surface of the connecting end of the sleeve and the mounting seat I be point C, the orthogonal projection of point C on the axis I be point c; any point on the inner bottom surface of the end of the through hole I of the sleeve be point P, the orthogonal projection of point P on the axis I be point p; the center of the ball head be point O, point O is located on the axis I;

[0043] When the ball head contacts the working surface, the axis I and the axis II coincide;

[0044] In order to ensure that the guide claw is in the open state when the ball head contacts the working surface, and the flange can cooperate with the claw, it is necessary to have:

[0045] ae≤bO≤ag

[0046] Wherein, ae is the distance between point a and point e, ag is the distance between point a and point g, bO is the distance between point b and the center of the ball head O;

[0047] Let the ball head be limited by the ball head limiting assembly, and the spring is still in the initial state, the position of the center of the ball head O is point h; in order to ensure that the ball head can enter the ball head limiting assembly smoothly, it is necessary to have:

[0048] gh≤ab≤eh

[0049] wherein, gh is the axial travel of the ball head's center O from point g to point h, ab is the axial travel of the flange after entering the guide claw, eh is the axial travel of the ball head's center O from point e to point h;

[0050] In order to ensure that the guide claw can cooperate with the flange to pull the connecting assembly I, there is:

[0051] cp-S≥ab

[0052] wherein, S is the shortest axial distance of the spring being compressed, cp-S is the maximum travel of the butt rod along the sleeve;

[0053] When the connecting assembly I and the connecting assembly II are separated, in order to ensure that the flange can be separated from the claw, there is:

[0054]

[0055] wherein Q is the length of the claw of the guide claw opening radially when the center of the ball head axially moves to coincide with point e, aj is the distance from point a to point j, D is the diameter of the ball head, d is the diameter of the butt rod, ej is the distance from point e to point j, and l is the maximum radial cooperation length of the flange and the claw.

[0056] Further, the ball head limiting assembly includes an electric push rod, a check claw, and a reinforcing frame;

[0057] The reinforcing frame is a "U" shaped structure integrally formed by two vertical plates II and a horizontal plate II, one end of each vertical plate II is connected to the end of the horizontal plate II, and the other end is fixedly arranged on the mounting seat II through the outer folded edge, and the reinforcing frame and the mounting seat II enclose a space I; the horizontal plate II of the reinforcing frame is provided with a through hole II, the through hole II is coaxially arranged with the mounting seat I, and the diameter of the through hole II is greater than the diameter of the ball head;

[0058] The check claw is an "L" shaped structure, one end of the check claw is connected to the output end of the electric push rod, the other end is provided with a groove, the end of the check claw where the groove is located is parallel to the electric push rod, and the end of the check claw where the groove is located can enter and exit the space I along the opening of the side of the reinforcing frame under the drive of the electric push rod;

[0059] When the end of the check claw where the groove is located enters the space I, the groove can cooperate with the butt rod to limit the ball head;

[0060] When the end of the check claw where the groove is located leaves the space I, the groove can release the limitation of the ball head.

[0061] A rigid-flexible connection switching method for a multi-section pipe robot, based on a rigid-flexible composite connection device for a pipe robot, the specific method being as follows:

[0062] Let the pipe robot connected with the connection device II be the first section robot, and the pipe robot connected with the connection device I be the second section robot;

[0063] The steps of switching the first section robot and the second section robot from flexible connection to rigid connection are as follows:

[0064] Step one: drive the first section robot to retreat, while the second section robot is in the braking state, the distance between the two section robots is constantly shortened, and the rope is constantly recovered under the action of the pulley box;

[0065] Step two: the capture surface of the connection assembly II of the first section robot contacts the ball head of the connection assembly I of the second section robot, and the attitude error of the ball head is corrected;

[0066] Step three: the ball head completely passes through the capture surface, enters the working surface through the transition surface I, and makes all the guide claws of the connection assembly II expand radially outward;

[0067] Step four: the ball head completely passes through the working surface, passes through the transition surface II, and all the guide claws are reset under the action of the torsional spring; the ball head continues to enter the ball head limiting assembly, the ball head limiting assembly limits the ball head, the distance between the two section robots reaches the shortest, the rope no longer shrinks, and the preliminary rigid connection between the two section pipe robots is realized;

[0068] Step five: the second section robot stops braking, the first section robot continues to advance, the spring is compressed, the clamping claws of the guide claws contact the flange, and the complete rigid connection between the two section pipe robots is realized;

[0069] The steps of switching the first section robot and the second section robot from rigid connection to flexible connection are as follows:

[0070] Step one: the ball head limiting assembly releases the limitation of the ball head;

[0071] Step two: the ball head contacts the working surface through the transition surface II under the elastic action of the spring, and makes all the guide claws of the connection assembly II expand radially outward;

[0072] Step three: drive the first section pipe robot to advance, the second section pipe robot is braked, the distance between the two section robots is increased, the pulley box releases the rope, and the flexible connection of the two section robots is realized.

[0073] Beneficial effects:

[0074] (1) When it is necessary to switch from a flexible connection to a rigid connection, the ball head enters the ball head limiting assembly along the guide channel; when it is necessary to switch from a rigid connection to a flexible connection, the ball head disengages from the connecting assembly II along the guide channel. One end of the cable assembly is connected to the mounting base I, and the other end is connected to the mounting base II, thus realizing a flexible connection between the connecting assembly I and the connecting assembly II. This realizes the switching between rigid and flexible connections between multi-section pipe robots, transforming the bending of multi-section pipe robots into the sequential bending of several single-section pipe robots, solving the problem of interference when multi-section pipe robots bend, and enabling them to pass through narrow bends with small curvature radii and T-shaped pipes, thereby improving the bending performance of pipe robots.

[0075] (2) The pull box of the present invention can provide a retraction force for the rope, thereby providing a connection component II to the connection component I.

[0076] The traction force is used to achieve flexible traction; the movable pulley can reduce the load on a single rope by half and improve the overall load capacity; the guide wheel can guide the rope, reduce the stiffness resistance of the wire rope, improve the stability of the flexible connection, and at the same time ensure the smooth release and retraction of each rope.

[0077] (3) The present invention has four pull boxes. The outlet of the rope of the pull box is evenly arranged along the circumference of the mounting base I, which can ensure that no torsional torque is generated on the pipeline robot when the flexible connection is used for traction, thereby improving the traction stability.

[0078] (4) The guide channel of the present invention is the space enclosed by the end faces of the vertical plates I of all the guide claws, and the right end of the horizontal plate I is connected to the mounting base I by a torsion spring pin, thereby enabling the guide channel to adapt to different...

[0079] The diameter of the ball head allows for free design of the ball head.

[0080] (5) The acute angle between the capturing surface and axis II of the present invention is α, the acute angle between the transition surface I and axis II is β, β < α, the acute angle between the transition surface II and axis II is γ, γ < α, the ball head and the capturing surface are in contact through a high pair, thereby ensuring that the capturing surface can automatically correct the attitude angle error of the ball head and realize automatic and rapid alignment between the connecting component I and the connecting component II.

[0081] (6) The claws and flanges of the present invention can improve the connection stiffness and achieve a stable rigid connection between the connecting component I and the connecting component II when the connecting component II is used to pull the connecting component I.

[0082] In addition, the spring can ensure that the ball head enters the guide channel and contacts the working surface from the ball head limiting assembly when switching from rigid connection to flexible connection, thereby opening the guide claw and separating the clamping claw from the flange, and achieving the release of rigid connection between the connection assembly I and the connection assembly II.

[0083] (7) The present application only needs to drive the pipeline robot, control the braking of the pipeline robot, and control the electric push rod to realize the automatic switching of the multi-section pipeline robot between rigid and flexible connections in the pipeline, which is mature in technology and simple in control, and does not need to manually realize rigid and flexible switching. BRIEF DESCRIPTION OF DRAWINGS

[0084] Fig. 1 is a prior art peristaltic pipeline robot;

[0085] Fig. 2 is a prior art passive rigid connection device I;

[0086] Fig. 3 is a prior art passive rigid connection device II;

[0087] Fig. 4 is a prior art active mechanical arm type connected pipeline robot;

[0088] Fig. 5 is a prior art flexible connection device;

[0089] Fig. 6 is a schematic view of interference of the multi-section pipeline robot passing through a bent pipe;

[0090] Fig. 7 is a schematic view of the rigid and flexible composite connection device for the pipeline robot (flexible connection) of the present application; Fig. 8 is a schematic view of the rigid and flexible composite connection device for the pipeline robot (rigid connection) of the present application; Fig. 9 is a schematic view of the connection assembly I of the present application;

[0091] Fig. 10 is a schematic view of the connection assembly II of the present application;

[0092] Fig. 11 is a layout of the steel wire rope outlet;

[0093] Fig. 12 is a structure view of the guide claw;

[0094] Fig. 13 is an end face angle view of the guide claw;

[0095] Fig. 14 is a process view of the self-docking of the rigid and flexible composite connection device for the pipeline robot of the present application; Fig. 15 is a schematic view of the key size of the rigid connection part;

[0096] Fig. 16 is a schematic view of the ball head limiting assembly;

[0097] Fig. 17 is a structure view of the check claw;

[0098] Fig. 18 is a soft-rigid switching process; wherein (a) flexible connection; (b) the guiding claw capture surface is in contact with the docking ball head; (c) the docking ball head is in contact with the working surface; (d) the docking ball head is limited; (e) rigid connection;

[0099] Fig. 19 is a rigid-soft switching process; (a) the ball head props up the guiding claw; (b) flexible connection;

[0100] wherein 1 is a connection assembly I, 2 is a connection assembly II, 3 is a mounting seat I, 4 is a docking ball head, 5 is a docking rod, 6 is a sleeve, 7 is a wire box, 8 is a guide wheel, 9 is a mounting seat II, 10 is a guiding claw, 11 is a movable pulley, 12 is a ball head limiting assembly; 13 is an electric push rod, 14 is a check claw, 15 is a reinforcing frame, 16 is a guide wheel base, 17 is a pin hole, 18 is a capture surface, 19 is a transition surface I, 20 is a working surface, 21 is a transition surface II, 22 is a flange, 23 is a pulley base, 24 is a clamping claw, 25 is a spring, and 26 is a groove. DETAILED DESCRIPTION

[0101] The present application will be described in detail below with reference to the accompanying drawings and examples.

[0102] Example 1

[0103] The present embodiment provides a rigid-flexible composite connection device for a pipeline robot, for connecting multiple sections of a pipeline robot.

[0104] The pipeline robot has at least one driving section.

[0105] Referring to Figs. 7 and 8, the rigid-flexible composite connection device comprises a connection assembly I and a connection assembly II.

[0106] The connection assembly I is arranged on one section of the pipeline robot, and the connection assembly II is arranged on an adjacent section of the pipeline robot. The connection assembly I and the connection assembly II can switch between rigid connection and flexible connection between two sections of the pipeline robot. When walking in a straight pipeline, rigid connection is used to facilitate overall driving and implementation of the functions of the pipeline robot. When passing through a curved pipeline, the connection is switched to flexible connection, and the driving section flexibly pulls the functional section, converting the bending of the multiple-section pipeline robot into the sequential bending of a plurality of single-section pipeline robots. This not only enables the pipeline robot to adapt to the pipeline autonomously, but also prevents interference between two sections of the pipeline robot when bending, thereby improving the bending performance of the multi-section robot.

[0107] Referring to Fig. 9, the connection assembly I comprises a mounting seat I 3, a cable assembly, and a docking ball rod. Referring to Fig. 10, the connection assembly II comprises a mounting seat II 9, a ball head guiding assembly, and a ball head limiting assembly 12.

[0108] The mounting seat I 3 is fixedly arranged on one pipe robot, and the mounting seat II 9 is fixedly arranged on another pipe robot;

[0109] One end of the cable assembly is connected with the mounting seat I 3, and the other end is connected with the mounting seat II 9; the cable in the cable assembly can be retracted or extended according to the distance between the connecting assembly I and the connecting assembly II;

[0110] The ball head guide assembly is arranged on the mounting seat II 9, and an axial guide channel is arranged in the ball head guide assembly; the ball head limiting assembly 12 is arranged on the mounting seat II 9 and located between the guide channel and the mounting seat II 9; one end of the butt joint ball rod is connected with the mounting seat I 3, and the other end is provided with the ball head 4; the ball head 4 can enter or exit the ball head limiting assembly 12 along the guide channel, and the ball head limiting assembly 12 is used for limiting or releasing the ball head 4;

[0111] When the ball head limiting assembly 12 limits the ball head 4, the two pipe robots are rigidly connected; when the ball head limiting assembly 12 releases the ball head 4, the ball head 4 can be separated from the connecting assembly II along the guide channel, and the two pipe robots are connected through the cable assembly, so that the flexible connection between the two pipe robots is realized.

[0112] In the embodiment, the ball head 4 of the connecting assembly I and the ball head limiting assembly 12 of the connecting assembly II are connected, so that the rigid connection between the connecting assembly I and the connecting assembly II is realized; one end of the cable assembly is connected with the mounting seat I 3, and the other end is connected with the mounting seat II 9, so that the flexible connection between the connecting assembly I and the connecting assembly II is realized.

[0113]

[0114] When it is needed to switch from the rigid connection to the flexible connection, the ball head 4 is separated from the connecting assembly II along the guide channel, and the two pipe robots are connected through the cable assembly; when it is needed to switch from the flexible connection to the rigid connection, the ball head 4 is made to enter the ball head limiting assembly 12 along the guide channel; so that the switching between the rigid connection and the flexible connection between the multiple pipe robots is realized, the over-bending of the multiple pipe robots is converted into the over-bending of the single pipe robots in sequence, the problem that the over-bending of the multiple pipe robots will interfere is solved, the pipe robot can pass through the small-curvature-radius narrow bend and the T-shaped pipe, and the over-bending performance of the pipe robot is improved. In addition, the ball head guide assembly is arranged in the embodiment, and the autonomous butt joint between the two pipe robots can be realized.

[0115] ​The mounting seat I 3 is a cylindrical shell structure with one end open and one end closed, and the closed end of the mounting seat I 3 is fixedly connected with the corresponding pipeline robot; the mounting seat II 9 is a circular plate; the central axis of the mounting seat I 3 is the axis I, and the central axis of the mounting seat II 9 is the axis II; in specific embodiments, the outer diameters of the mounting seat I 3 and the mounting seat II 9 are both 170 mm.

[0116] Referring to FIG. 9, the cable assembly includes three or more pull boxes 7, the pull boxes 7 are provided with retractable ropes, and the pull boxes 7 can provide recovery force for the ropes, so as to realize the traction of the connecting assembly II by the ropes; in specific embodiments, the ropes are steel wire ropes, and the outlets of the ropes on the pull boxes 7 are distributed along the circumference;

[0117] In one specific embodiment, the end of each rope is directly connected with the mounting seat II 9, so as to realize the flexible connection of the connecting assembly I and the connecting assembly II.

[0118] In another specific embodiment, three or more movable pulleys 11 are arranged on the mounting seat II 9, the movable pulleys 11 are opposite to the outlets of the ropes on the pull boxes 7 when rigidly connected, one end of each rope is fixedly connected with the mounting seat I 3 after winding around the opposite movable pulley 11, so as to realize the flexible connection of the connecting assembly I and the connecting assembly II; in specific embodiments, the movable pulleys 11 are arranged on the mounting seat II 9 through corresponding pulley bases 23. The arrangement of the movable pulleys 11 can reduce the load of half of the single ropes and improve the overall load capacity.

[0119] The same number of guide wheels 8 as the pull boxes 7 can also be arranged on the mounting seat I 3, the guide wheels 8 are arranged at the outlets of the ropes on the pull boxes 7 through guide wheel bases 16, and are used for guiding the ropes, reducing the rigidity resistance of the steel wire ropes, improving the stability of the flexible connection, and ensuring the smooth winding and unwinding of the ropes.

[0120] In specific embodiments, referring to FIG. 11, the number of the pull boxes 7 is four, and the outlets of the ropes of the pull boxes 7 are uniformly arranged along the circumference of the mounting seat I 3, so as to ensure that no torsional moment is generated on the pipeline robot when the flexible connection utilizes the ropes for traction, and the traction stability is improved.

[0121] The traction stability is improved.

[0122] The parameters of the pull box are as follows: rope length 2000mm, diameter 1mm, mass 0.015kg, dimensions 10mm*10mm*17mm, retraction force 30N, allowable load (single) 30kg. When the resistance of the pulled pipeline robot is lower than the retraction force of the pull box 30N, the wire rope will automatically retract, thus achieving flexible traction. By using the movable pulley 11, the total allowable load of the wire ropes of the four pull boxes 7 can reach 240kg.

[0123] Referring to Figure 10, the ball-head guide assembly consists of three or more guide claws 10. All guide claws 10 are mounted on the mounting base II 9 and arranged circumferentially. Each guide claw 10 is a "T"-shaped plate structure comprising a horizontal plate I and a vertical plate I. The two ends of the horizontal plate I are the left and right ends, respectively. The right end of the horizontal plate I is connected to the outer edge of the mounting base I 3 via a torsion spring pin. The vertical plates I of the guide claws 10 are all oriented towards axis II. The end faces of the vertical plates I are arched. The guide channel is the space enclosed by the end faces of the vertical plates I of all the guide claws 10. In a specific embodiment, four guide claws 10 are used, and the four guide claws are evenly arranged along the circumference of the mounting base II 9.

[0124] Referring to Figure 12, the arched end face of the vertical plate I of each guide claw 10 includes, from left to right, sequentially...

[0125] The capture surface 18, transition surface I 19, working surface 20, and transition surface II 21 are connected; a transition fillet is provided at the connection between the capture surface 18, transition surface I 19, working surface 20, and transition surface II 21;

[0126] Referring to Figure 13, the acute angle between the capturing surface 18 and axis II is α, the acute angle between the transition surface I19 and axis II is β, β < α; the angle between the working surface 20 and axis II is θ, θ = 180. That is, the working surface 20 is parallel to the axis II; the acute angle between the transition surface II21 and the axis II is γ, where γ < α; by setting the capture surface 18, when the ball head 4 contacts the connecting component II, the attitude angle error of the ball head 4 can be automatically corrected, and the ball head 4 can be guided so that the ball head 4 can contact the capture surface 18, the transition surface I19, the working surface 20 and the transition surface II21 in sequence before entering the ball head limiting component 12, thus realizing the rigid connection between the connecting component I1 and the connecting component II2; in addition, the setting of the transition surface II21 makes it easy for the ball head 4 to smoothly enter the guide channel after leaving the ball head limiting component 12 when the rigid connection is released, so that the ball head 4 can disengage from the connecting component II2 along the guide channel.

[0127] In a specific embodiment, α = 61.5°, β = γ = 30°; the length of the normal projection of the capturing surface 18 on the axis II is 6mm, the length of the normal projection of the transition surface I 19 and the transition surface II 21 on the axis II is 5mm, and the length of the capturing surface 18

[0128] is 18mm.

[0129] In a specific embodiment, referring to Figs. 9 and 14, the connecting rod further comprises a sleeve 6, a connecting rod 5 and a spring 25; one end of the sleeve 6 is fixedly connected with the mounting base I 3, and the other end is provided with a through hole I; one end of the connecting rod 5 is coaxially located in the sleeve 6 through the through hole I, and the other end is connected with the ball head 4; the end of the connecting rod 5 located in the sleeve 6 is provided with a coaxial annular edge, the spring 25 is located in the sleeve 6 and is sleeved outside the connecting rod 5, one end of the spring 25 abuts against the edge of the connecting rod 5, and the other end abuts against the end where the through hole I of the sleeve 6 is located.

[0130] The left end of the horizontal plate I of each guide claw 10 is provided with a clamping jaw 24, and the mounting base I 3 is provided with a coaxial annular flange 22, and the clamping jaws 24 of all the guide claws 10 can be connected with the flange 22.

[0131] Referring to Fig. 14, in the process of switching the rigid connection, the distance between the two pipeline robots is reduced, when the ball head 4 abuts against the end surface of the vertical plate I of the guide claw 10 after entering the guide channel, the guide claw 10 is opened under the action of the ball head 4, so that the diameter of the circumscribed circle of the inner edges of all the clamping jaws 24 arranged along the circumference is greater than the outer diameter of the flange 22; when the ball head 4 passes through the guide channel, the guide claw 10 is reset under the action of the torsional spring, the clamping jaw 24 abuts against the outer circumference of the mounting base I 3, and the distance between the two pipeline robots is further increased, so as to realize the cooperation of the clamping jaw 24 and the flange 22, realize that the pipeline robots connected by the connecting assembly II pull the pipeline robots connected by the connecting assembly I, and thus realize the further rigid connection between the connecting assembly I 1 and the connecting assembly II 2.

[0132] In a specific embodiment, the force center of the cooperation of the clamping jaw 24 of each guide claw 10 and the flange 22 is parallel to the connecting center of the same guide claw 10, so as to eliminate the reverse torque.

[0133] When the ball head 4 disengages from the connecting assembly II 2, the ball head limiting assembly 12 releases its restriction on the ball head 4. Under the elastic force of the spring 25, the ball head 4 enters the guide channel. When the ball head 4 abuts against the end face of the vertical plate I of the guide claw 10, the guide claw 10 opens under the action of the ball head 4, making the diameter of the outer circle of the inner edge of all the claws 24 arranged along the circumference greater than the outer diameter of the flange 22. By increasing the distance between the two pipe robots, the claws 24 can be disengaged from the flange 22 and the ball head 4 can be disengaged from the guide channel, thus releasing the rigid connection between the two pipe robots.

[0134] In one specific embodiment, referring to Figure 15, to ensure that the rigid-flexible composite connection device can achieve connection...

[0135] To ensure that the components can function without interference, it is necessary to limit their important dimensions.

[0136] Let point A be any point on the mating surface of the jaw 24 and flange 22, and let point A be the orthographic projection of point A onto axis II. Let point E be any left endpoint of the working surface 20, and let point E be the orthographic projection of point E onto axis II. Let point F be any point on the centerline of the working surface 20 along the axial direction, and let point F be the orthographic projection of point F onto axis II. Let point G be any right endpoint of the working surface 20, and let point G be the orthographic projection of point G onto axis II. Let point J be any point on the axis of the pin hole 17 of the mounting base II9, and let point J be the orthographic projection of point J onto axis II.

[0137] Let any point on the mating surface of flange 22 and jaw 24 be point B, and the orthographic projection of point B on axis I be point b; let any point on the inner bottom surface of the end of sleeve 6 that connects to mounting base I3 be point C, and the orthographic projection of point C on axis I be point c; let any point on the inner bottom surface of the end of sleeve 6 where through hole I is located be point P, and the orthographic projection of point P on axis I be point p; let the center of ball head 4 be point O, and point O be located on axis I;

[0138] When ball head 4 contacts the working surface, axis I and axis II coincide;

[0139] (1) To ensure that the guide claw 10 is in the open state and the flange 22 can cooperate with the chuck 24 when the ball head 4 contacts the working surface, then:

[0140] ae≤bO≤ag formula (1)

[0141] wherein ae is the distance between point a and point e, ag is the distance between point a and point g, and bO is the distance between point b and the ball center O of the ball head 4;

[0142] In specific embodiments, bO = af, wherein af is the distance between point a and point f.

[0143] (2) When the ball head 4 is positioned by the ball head positioning assembly 12 and the spring 25 is still in the initial state, the position of the ball center O is point h. To ensure that the ball head 4 can smoothly enter the ball head positioning assembly 12, the following equation is satisfied:

[0144] gh≤ab≤eh Equation (2)

[0145] wherein gh is the axial stroke of the ball center O of the ball head 4 from point g to point h, ab is the axial stroke of the flange 22 after entering the guide claw 10, and eh is the axial stroke of the ball center O of the ball head 4 from point e to point h.

[0146] In specific embodiments, ab = fh, wherein fh is the axial stroke of the ball center O of the ball head 4 from point f to point h.

[0147] (3) To ensure that the guide claw 10 can cooperate with the flange 22 to pull the connecting assembly I, the following equation is satisfied:

[0148] wherein S is the shortest axial distance of the spring 25 being compressed, and cp-S is the maximum stroke of the abutting rod 5 moving along the sleeve 6. In specific embodiments, cp-S = ab.

[0149] (4) When the connecting assembly I1 and the connecting assembly II2 are separated, to ensure that the flange 22 can be separated from the claw 24

[0150] of the guide claw 10, the following equation is satisfied:

[0151] Equation (4)

[0152] wherein Q is the length of the claw 24 of the guide claw 10 opening along the radial direction when the ball center of the ball head 4 moves axially to coincide with point e, aj is the distance from point a to point j, D is the diameter of the ball head 4, d is the diameter of the abutting rod 5, ej is the distance from point e to point j, and l is the maximum radial fitting length of the flange 22 and the claw 24.

[0153] In the embodiment, the diameter d of the connecting rod 5 is 7 mm, the diameter D of the ball head 4 is 18 mm, and the maximum radial matching length l of the flange 22 and the claw 24 is 5 mm; the axial length of the guide claw 10 is 24 mm.

[0154] Other dimensions are determined by the non-interference condition between other components.

[0155] Referring to FIG. 16, the ball head limiting assembly 12 is located on the right side of the vertical plate I of the guide claw 10, and includes an electric push rod 13, a check claw 14, and a reinforcing frame 15.

[0156] The reinforcing frame 15 is a "U" shaped structure integrally formed by two vertical plates II and a horizontal plate II, one end of each vertical plate II is connected to the end of the horizontal plate II, and the other end is fixedly arranged on the mounting seat II 9 through the outer folded edge, and the reinforcing frame 15 and the mounting seat II 9 form a space I; a through hole II is arranged on the horizontal plate II of the reinforcing frame 15, the through hole II is coaxially arranged with the mounting seat I 3, and the diameter of the through hole II is greater than the diameter of the ball head 4.

[0157] Referring to FIG. 17, the check claw 14 is an "L" shaped structure, one end of the check claw 14 is connected to the output end of the electric push rod 13, the other end is provided with a groove 26, the end where the groove 26 of the check claw 14 is located is parallel to the electric push rod 13, and the end where the groove 26 of the check claw 14 is located can enter and exit the space I along the opening of the side edge of the reinforcing frame 15 under the drive of the electric push rod 13; the reinforcing frame 15 mainly bears the reset spring tension load when the check claw is constrained, and the stiffness of the reinforcing check claw 14 is enhanced.

[0158] When the end where the groove of the check claw 14 is located enters the space I, the groove can be matched with the connecting rod 5 to limit the ball head 4;

[0159] When the end where the groove of the check claw 14 is located leaves the space I, the groove can release the limitation of the ball head 4.

[0160] In the embodiment, the parameters of the electric push rod 13 are as follows: the rated voltage is 24V, the rated current is 0.025A, the minimum length is 81.5mm, the maximum length is 117.5mm, the thrust is 150N, the self-locking force is 195N, and the maximum speed is 4mm / s.

[0161] Embodiment 2:

[0162] The embodiment provides a rigid-flexible connection switching method for a multi-section pipeline robot.

[0163] Taking rigid-flexible connection switching of a two-section pipeline robot as an example, a pipeline robot connected with the connection device II is a first-section robot, and a pipeline robot connected with the connection device I is a second-section robot.

[0164] Referring to FIG. 18, the steps of switching the first-section robot and the second-section robot from flexible connection to rigid connection are as follows.

[0165] Step one: the first-section robot is driven to retreat, and the second-section robot is in a braking state, the distance between the two-section robots is continuously shortened, and the rope is continuously retracted under the action of the pulley box 7.

[0166] Step two: the capturing surface 18 of the connection assembly II 2 of the first-section robot is in contact with the ball head 4 of the connection assembly I 1 of the second-section robot, and the attitude error of the ball head 4 is corrected.

[0167] Step three: the ball head 4 completely passes through the capturing surface 18, enters the working surface 20 through the transition surface I 19, and makes all the guide claws 10 of the connection assembly II expand radially outward.

[0168] Step four: the ball head 4 completely passes through the working surface 20, passes through the transition surface II 21, and all the guide claws 10 are reset under the action of the torsional spring; the ball head 4 continues to enter the ball head limiting assembly 12, the ball head limiting assembly 12 limits the ball head 4, the distance between the two-section robots reaches the shortest, the rope no longer shrinks, and the preliminary rigid connection between the two-section pipeline robots is realized.

[0169] The specific way in which the ball head limiting assembly 12 limits the ball head 4 is that the ball head 4 enters the reinforced frame 15, the check claw 14 is matched with the butt joint rod 5 by controlling the electric push rod 13, and the ball head 4 is limited.

[0170] Step five: the second-section robot stops braking, the first-section robot continues to advance, the spring 25 is compressed, the guide claw 10 of the guide claw 10 is in contact with the clamping claw 24 of the guide claw 10, and the clamping claw 24 of the guide claw 10 is in contact with the flange 22.

[0171] The guide claw 10 of the guide claw 10 is in contact with the clamping claw 24 of the guide claw 10, and the clamping claw 24 of the guide claw 10 is in contact with the flange 22.

[0172] The steps of switching the first-section robot and the second-section robot from rigid connection to flexible connection are as follows.

[0173] Referring to FIG. 19, step one: the ball head limiting assembly 12 releases the limiting of the ball head 4, specifically: through the control of the electric push rod 13 to make the check pawl 14 release the cooperation with the butt joint rod 5;

[0174] Step two: the ball head 4 contacts the working surface 20 through the transition surface II 21 under the elastic action of the spring 25, so that all the guide claws 10 of the connecting assembly II expand radially outward;

[0175] Step three: the driving first section pipe robot advances, the secondary section pipe robot brakes, the distance between the two section robots is increased, the pull wire box 7 releases the rope, and the flexible connection of the two section robots is realized.

[0176] To sum up, the above is only a preferred embodiment of the present application, and is not used to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A rigid-flexible composite connection device for a pipeline robot, characterized in that, Used to connect multi-section pipe robots, in which at least one section is a drive section; The rigid-flexible composite connection device includes: connection component I and connection component II; Connection assembly I includes mounting base I, cable assembly, and docking ball; Connection component II includes mounting base II, ball head guide component, and ball head limiting component; Mounting base I is fixedly installed on one section of the pipeline robot, and mounting base II is fixedly installed on the adjacent section of the pipeline robot; One end of the cable assembly is connected to mounting base I, and the other end is connected to mounting base II; the rope inside the cable assembly can be extended or retracted depending on the distance between connecting component I and connecting component II; The ball head guide assembly is mounted on mounting base II, and an axial guide channel is provided inside the ball head guide assembly; the ball head limiting assembly is mounted on mounting base II and is located between the guide channel and mounting base II; one end of the connecting ball rod is connected to mounting base I, and the other end is provided with a ball head; the ball head can enter and exit the ball head limiting assembly along the guide channel, and the ball head limiting assembly is used to limit or release the ball head; When the two sections of the pipeline robot are rigidly connected, the ball head limiting component limits the ball head; when the two sections of the pipeline robot are flexibly connected, the two sections of the pipeline robot are connected by a rope assembly. The ball-head guide assembly has three or more guide claws; all guide claws are mounted on the mounting base II and arranged circumferentially, and each guide claw is a "T"-shaped plate structure including a horizontal plate I and a vertical plate I. Let the two ends of the horizontal plate I be the left end and the right end, respectively, and let the central axis of the mounting base II be axis II; The right end of the horizontal plate I is connected to the outer edge of the mounting base I by a torsion spring pin. The vertical plates I of the guide claws are all oriented towards the axis II. The end face of the vertical plate I is arched. The guide channel is the space enclosed by the end faces of the vertical plates I of all the guide claws. Each guide claw has a locking claw at the left end of the horizontal plate I, and the mounting base I has a coaxial annular flange. The locking claws of all guide claws can be connected with the flange. During the switching of rigid connection, the distance between the two pipeline robots is reduced. When the ball head enters the guide channel and abuts against the end face of the vertical plate I of the guide claw, the guide claw opens under the action of the ball head, so that the diameter of the outer circle of the inner edge of all the claws set along the circumference is greater than the outer diameter of the flange. After the ball head passes through the guide channel, the guide claw is reset under the action of the torsion spring, and the chuck abuts against the outer circumference of the mounting base I. By increasing the distance between the two pipe robots, the chuck and the flange can be engaged. When the ball head disengages from the connecting assembly II, the ball head limiting assembly releases its restraint on the ball head. Under the elastic force of the spring, the ball head enters the guide channel. When the ball head abuts against the end face of the vertical plate I of the guide claw, the guide claw opens under the action of the ball head, making the diameter of the outer circle of the inner edge of all the claws arranged along the circumference greater than the outer diameter of the flange. By increasing the distance between the two pipe robots, the claws can be disengaged from the flange and the ball head can be disengaged from the guide channel, thus breaking the rigid connection between the two pipe robots and switching to a flexible connection.

2. The rigid-flexible composite connection device for a pipeline robot as described in claim 1, characterized in that, The cable assembly includes three or more pull boxes, each containing a retractable rope that provides a retractable force to the rope; the rope outlets on the pull boxes are distributed circumferentially. Mounting base II is equipped with three or more movable pulleys. In the case of rigid connection, the movable pulleys are aligned with the outlets of the ropes on the cable box. One end of each rope is wound around the movable pulley opposite it and then fixedly connected to mounting base I. Mounting base I is equipped with the same number of guide wheels as the cable box. The guide wheels are located at the rope exit of the cable box and are used to guide the rope.

3. The rigid-flexible composite connection device for a pipeline robot as described in claim 2, characterized in that, There are four pull boxes; the outlets of the pull boxes are evenly distributed around the circumference of mounting base I.

4. The rigid-flexible composite connection device for a pipeline robot as described in claim 1, characterized in that, The arched end face of the vertical plate I of each guide claw includes a capture surface, transition surface I, working surface and transition surface II connected sequentially from left to right; The acute angle between the capturing surface and axis II is α, and the acute angle between the transition surface I and axis II is β, where β < α; The working surface is parallel to axis II; the acute angle between the transition surface II and axis II is γ, where γ < α.

5. The rigid-flexible composite connection device for a pipeline robot as described in claim 4, characterized in that, The ball joint also includes a sleeve, a connecting rod, and a spring; one end of the sleeve is fixedly connected to the mounting base I, and the other end is provided with a through hole I; one end of the connecting rod passes through the through hole I and is coaxially located inside the sleeve, and the other end is connected to the ball head; the end of the connecting rod located inside the sleeve is provided with a coaxial annular edge, the spring is located inside the sleeve and sleeved outside the connecting rod, one end of the spring abuts against the edge of the connecting rod, and the other end abuts against the end of the sleeve where the through hole I is located.

6. The rigid-flexible composite connection device for a pipeline robot as described in claim 5, characterized in that, Let point A be any point on the mating surface of the jaw and the flange, and let point A be the orthographic projection of point A onto axis II. Let point E be any left endpoint of the working surface, and let point E be the orthographic projection of point E onto axis II. Let point F be any point on the centerline of the working surface along the axial direction, and let point F be the orthographic projection of point F onto axis II. Let point G be any right endpoint of the working surface, and let point G be the orthographic projection of point G onto axis II. Any point on the axis of the pin hole of mounting base II is called point J, and the orthographic projection of point J on axis II is called point j. Let the central axis of mounting base I be axis I, any point on the flange and its mating surface with the jaws be point B, and the orthographic projection of point B onto axis I be point b; any point on the inner bottom surface of the sleeve's connection end with mounting base I be point C, and point C on axis I... The orthographic projection of point I is point c; any point on the inner bottom surface of the end where the through hole I of the sleeve is located is point P, and the orthographic projection of point P on axis I is point p; the center of the ball head is point O, and point O is located on axis I. When the ball head contacts the working surface, axis I and axis II coincide; To ensure that the guide claw is in the open state and the flange can engage with the chuck when the ball head contacts the working surface, then: ae≤bO≤ag Where ae is the distance between point a and point e, ag is the distance between point a and point g, and bO is the distance between point b and the center O of the sphere. When the ball head is limited by the ball head limiting component and the spring is still in its initial state, the position of the ball center O is point h; to ensure that the ball head can smoothly enter the ball head limiting component, we have: gh≤ab≤eh Where gh is the axial travel of the ball head's center O from point g to point h, ab is the axial travel of the flange after entering the guide claw, and eh is the axial travel of the ball head's center O from point e to point h. To ensure that the guide claw can engage with the flange to pull the connecting assembly I, the following applies: cp-S≥ab Where S is the shortest axial distance the spring is compressed, and cp-S is the maximum stroke the connecting rod can travel along the sleeve; when connecting assembly I disengages from connecting assembly II, to ensure the flange can disengage from the chuck, then: Where Q is the radial extension length of the guide claw when the ball head moves axially to coincide with point e, aj is the distance from point a to point j, D is the diameter of the ball head, d is the diameter of the connecting rod, ej is the distance from point e to point j, and l is... The maximum radial engagement length between the flange and the jaw.

7. A rigid-flexible composite connection device for a pipeline robot as described in any one of claims 5-6, characterized in that, The ball head limiting assembly includes an electric push rod, a check pawl, and a reinforcement bracket; The reinforcement frame is a U-shaped structure integrally formed from two vertical plates II and one horizontal plate II. One end of each vertical plate II is connected to the end of the horizontal plate II, and the other end is fixed to the mounting base II through the outward folded edge. The reinforcement frame and the mounting base II form a space I. The horizontal plate II of the reinforcement frame is provided with a through hole II, which is coaxial with the mounting base I, and the diameter of the through hole II is larger than the diameter of the ball head. The check pawl has an "L" shaped structure. One end of the check pawl is connected to the output end of the electric push rod, and the other end is provided with a groove. The end of the check pawl with the groove is parallel to the electric push rod. The end of the check pawl with the groove can enter and exit space I through the opening on the side of the reinforcement frame under the drive of the electric push rod. When the groove of the check pawl enters space I, the groove can cooperate with the connecting rod to limit the ball head; When the end of the check claw with its groove leaves space I, the groove can release the constraint on the ball head.

8. A method for switching between rigid and flexible connections for a multi-section pipeline robot, based on the rigid-flexible composite connection device for a pipeline robot as described in any one of claims 6-7, the specific method being as follows: The pipeline robot connected to connecting device II is the first section robot, and the pipeline robot connected to connecting device I is the second section robot; The steps for switching the first and second robot segments from a flexible connection to a rigid connection are as follows: Step 1: Drive the first robot section backward, while the second robot section is in a braking state. The distance between the two robot sections is continuously shortened, and the rope is continuously retracted under the action of the pull box. Step 2: The capture surface of the first robot's connecting component II contacts the ball head of the second robot's connecting component I, guiding and correcting the ball head's attitude error; Step 3: The ball head passes completely through the capture surface, then through transition surface I and enters the working surface, causing all the guide claws of the connecting assembly II to expand radially outward; Step 4: The ball head completely passes through the working surface and transition surface II. All guide claws are reset under the action of the torsion spring. The ball head continues to enter the ball head limiting assembly, which limits the ball head. The distance between the two robot sections is minimized, the rope no longer retracts, and the initial rigid connection between the two pipe robot sections is achieved. Step 5: The second robot stops braking, the first robot continues to move forward, the spring is compressed, and the guide claw's pawl contacts and engages with the flange to achieve a completely rigid connection between the two pipe robot sections; The steps for switching from a rigid connection to a flexible connection between the first and second robot sections are as follows: Step 1: Release the ball head limiting component from limiting the ball head; Step 2: Under the elastic action of the spring, the ball head passes through transition surface II and contacts the working surface, causing all the guide claws of connecting assembly II to expand radially outward; Step 3: Drive the first section of the pipeline robot forward, brake the second section of the pipeline robot, increase the distance between the two sections of the robot, and release the rope through the cable box to achieve a flexible connection between the two sections of the robot.

Images