Transportation module for inspection robot

Abstract

The invention relates to transportation means capable of travelling through pipelines and can be used as a supporting structural element of a transportation module for an autonomous in-pipe inspection robot for inspecting the condition of pipelines typically having significant variations in pipe diameters, local variations in direction in the vertical and horizonal planes, as well as different branches. The technical result of the proposed invention is the adaptability of the transportation module support during the balancing of the robot, lending the robot static stability, reducing the load on the supporting wheel and improving the engagement thereof with the inside surface of a pipe.

Description

TRANSPORT MODULE OF THE DIAGNOSTIC ROBOT

[0001] The invention relates to vehicles capable of moving inside pipelines and can be used as a supporting structural element of a transport module of an in-pipe autonomous diagnostic robot for conducting video diagnostics, non-destructive testing of the condition of both main and field and process pipelines, which are characterized by significant differences in pipe diameters, local changes in direction in the vertical and horizontal planes, as well as pipeline branches when separating the flow of the transported product.

[0002] Currently, both traditional in-pipe flaw detection tools and autonomous robotic flaw detection scanners are used for in-pipe diagnostics. In-pipe tools move in the pipe under the action of the gas flow. Such devices can only be used on operating main gas pipelines.

[0003] An autonomous robotic diagnostic device designed for operation inside both main and field and process pipelines is known, for example, as a mobile "Vehicle for moving a robot in pipelines of complex configuration" according to patent PM170056 (2016), comprising a base with an electric motor mounted thereon, three wheel pairs located relative to each other at an angle of 120°, a mechanism for transmitting motion from the electric motor to the propeller with a tread and a mechanism for pressing the wheels to the surface of the pipeline, wherein the propeller is made in the form of a belt made with a tread on the outer side that touches the pipeline during operation of the device and a toothed profile corresponding to the profile of the toothed rim of the drive wheel on the inner side, which together with the gearbox represents a mechanism for transmitting motion from the electric motor to the propeller.Industrial and process pipelines are characterized by significant differences in pipe diameters of up to 150%, local changes in direction up to 180°, as well as branches (tees) of the pipeline when dividing the flow of the transported product. These design features are implemented using standardized connecting pipeline elements, respectively, transitions, sharply curved bends and tees. The disadvantage of the technical solution described above is the relatively low maneuverability in the presence of obstacles, long sections of pipelines inclined in the vertical plane, when passing the described connecting elements, especially sharply curved bends with a turning radius from one 1 to one and a half 1.5 internal diameters of the pipe and equal tees, as well as a relatively low accuracy of maintaining coaxiality relative to the pipeline axis, which significantly affects the diagnostic accuracy of a large number of measurement methods.

[0004] Also known is the "Robotized platform for in-pipe diagnostics" PM194854 (2019), comprising first and second supporting bases, each of which comprises three support legs with independent drives with wheels with independent drives, arranged at an angle of 120°, wherein the first and second supporting bases are rigidly attached by means of connecting flanges to the body of a full-rotary diagnostic module on its opposite sides, which is designed to install control and instrumental diagnostic means. Each of the six supporting legs with drive wheels at the end is a lever directed along the pipe axis with its base mounted on an independent rotary hinge of the lever rotation, ensuring the swing of the leg lever in the radial plane of the pipe. Accordingly, the hinge axis is directed tangent to the circumference of the pipe cross-section, and the hinges themselves are mounted on the supporting bases.Such a kinematic scheme of the platform with swinging leg levers allows to overcome transitions when it is necessary to move along a pipe with a conical inner surface by changing the angle of inclination of the levers to the pipe axis. Thus, when moving inside a pipe with the minimum possible diameter, the levers are practically extended along the pipe axis and have the largest angle of inclination to the axis when moving in a pipe with the maximum possible diameter, and when moving in a conical transition with a change in diameter, three independent hinges of the levers must coordinately change the angles of inclination of the three levers of the support legs sequentially on each supporting base.

[0005] The main disadvantage of this analogue is the difficulty of overcoming sharply curved bends with a turning angle of 90° or more, especially for pipes with the smallest possible small diameter under the condition of passing the transition. This is due to the rather large length of the robotic platform with extended legs. At the same time, passing turns by this platform is associated with significant difficulties, since when turning, the wheels external to the center of the turn must travel longer distances and, accordingly, rotate at a higher speed than the internal ones, while in order to comply with the kinematic conditions for passing a rigid structure in a curved pipe, all wheels will roll only with slippage, which also requires additional parasitic energy costs.The turning problem can be partially alleviated by changing the angles of the internal and external levers in relation to the wheel turning center, which leads to a noticeable deviation of the robot axis from the pipe axis and does not completely eliminate the phenomenon of wheel slippage. This is especially noticeable when turning with small radii and complicates and even makes it impossible to perform diagnostics by rotating the diagnostic module around the central part of the robot.

[0006] These problems are solved in the “Transport module of the in-pipe diagnostic robot” according to patent RU 2802493 (2022), accepted as a prototype.

[0007] The transport module of the in-pipe diagnostic robot comprises the first and second supporting bases containing three support legs with independent drive wheel propellers installed at an angle of 120°. The bases are connected on opposite sides to the central body intended for installation of the on-board equipment by means of two-axis hinges. When moving in straight sections of the pipe, the hinge turns are blocked, and when passing bend turns, coordinated hinge turns are provided independently around each pair of parallel axes of the hinge mobility degrees, for example, when passing turns in the horizontal plane and turns for lifting or lowering in the vertical plane. Part of the on-board equipment is carried outside the central body and installed on one or both supporting bases.The support legs are installed radially and consist of a fixed body and a movable section with a wheeled propeller mounted on it, and the movable section of the support telescopically extends or retracts using its own independent electric drive with a screw mechanism.

[0008] This kinematic diagram of the transport module ensures the passage of turns in the horizontal plane due to the free rotation of the unlocked (disinhibited) hinges with vertical axes and the regulation of the rotation speeds of the support wheels near and far in relation to the center of rotation.

[0009] When turning in the vertical plane after unlocking the hinges with horizontal axes, an uncontrolled "break" of the longitudinal axis of the transport module in the vertical plane may occur, which may be caused by insufficiently precise balancing of the transport module. Balancing in this case assumes such a distribution of the proper masses of the support bases and the central body together with the masses of the "proper" functional equipment installed on them, ensuring the movement of the transport module and diagnostic equipment, so that the horizontally installed transport module with locked hinges with a straight longitudinal axis after unlocking the hinges with vertical axes remains motionless and maintains a straight longitudinal axis.Such balancing is achieved as a result of a complex set of measures, firstly, during the design of the corresponding meticulous “balance” of the entire structure of the diagnostic robot with the possible and even mandatory addition of “parasitic” ballast weights, and, secondly, during the assembly and debugging of the assembled robot by specifying the masses of the ballast weights and their locations.It is obvious that the need to use ballast weights increases the diagnostic robot's own weight, the load on the wheels, the load on the wheel drives and the support leg extension drives, and increases the energy consumption of autonomous batteries, which will lead to a reduction in the autonomous operation time of the diagnostic robot inside the pipe, reduce the length of the inspected section of the pipe (on one battery charge), which will increase the number of passes and the time of inspection of the planned section of the pipe and, ultimately, increase the downtime of the pipeline and the significant financial losses of the operators directly associated with this.

[0010] It is important to note that this scheme (in the state with unlocked hinges) is statically unstable and sensitive to mass imbalance, but, nevertheless, has some resource for dynamic compensation of unbalanced moments caused by relatively small mass imbalance, due to the appropriate control of the rotation speeds of the upper and lower support drive wheels, which allows creating the necessary compensating torques around the horizontal axes applied to the bases in combination with the operation of the hinge-locking brakes.

[0011] At the same time, when passing obstacles, for example, annular welds up to 15-20 mm high of successively welded pipes (usually up to 10-12 m long) whose presence is indicated by difficulty in wheel rotation, which is judged by an increase in the current consumption of the motors, it is necessary to retract the wheels due to the operation of the radially directed linear screw drive of the wheel support. As practice shows, such a control circuit does not have sufficient speed and accuracy and requires a decrease in the robot's speed. Even greater difficulties arise when one wheel runs into a random obstacle, for example, a local area with bitumen deposits, in the inter-seam space of the pipe. Technical task

[0012] The objectives of the proposed invention are: imparting static stability to the kinematic diagram of the transport module of the diagnostic robot, reducing the load on the support wheel and improving its adhesion to the inner surface of the pipe, eliminating the use of balancing weights and simplifying the procedure for balancing the mass distribution of the diagnostic robot, as well as simplifying the overcoming of obstacles and increasing the energy efficiency of the robot. Solution to the problem

[0013] The task of imparting static stability to the kinematic diagram of the diagnostic robot is solved by changing the kinematic diagram of the support of the transport module by increasing the longitudinal line of support on the propeller pipe of the support leg, which is carried out by installing two drive wheels (motor wheels), each on its own hinged spring-loaded lever, which are directed along the longitudinal axis of the transport module forward and backward from the radially directed axis of the support leg. Obviously, for the static stability of the transport module of the robot with unlocked hinges within the elastic travel of the springs of the wheel levers, it is sufficient for the vector of the weight of the center of mass of the bases, taking into account the weight of the central part, to fall into a significantly increased zone of the support area formed by the front and rear wheels of the lower support legs in comparison with the prototype, in which the stability zone is a narrow strip along the line of connection of the contact spots of the wheels of the lower supports.

[0014] The task of reducing the load on the wheel and improving its adhesion to the inner surface of the pipe is solved by using two-wheel support for the legs of the robot transport module, giving the tire a toroidal shape with a tread and with a contact surface whose radius is smaller than the inner radius of the pipe, while the tires are made of a material with a high coefficient of friction.

[0015] The problem of eliminating the use of hanging "parasitic" ballast weights when balancing the robot and simplifying the balancing procedure is solved due to the fact that on each support leg each of the two drive motor wheels is mounted on the end of its own lever, the other end of which is mounted on the movable section using a cylindrical hinge and is spring-loaded relative to it using two identical compression springs symmetrically located relative to the axis of the lever, wherein the axis of the cylindrical hinge is directed perpendicular to the longitudinal axis of the robot, and the following capabilities are incorporated into the design of the support leg: changing the length of each lever, changing the position of the attachment point of each pair of springs on its lever and changing the amount of initial compression of each spring, and spring compression limiters are also installed.

[0016] In this case, each lever is made in the form of a two-section telescopic boom, the fixed section of which - the sleeve is connected by a hinge to the movable section of the leg support, and a movable section - a rod is installed in the sleeve, on which the mounting strips with springs are installed and secured in the required position, and a motor wheel is installed at the end of the rod.

[0017] In addition to this, each support is equipped with: a sensor that monitors the movement of the movable section relative to the fixed support body, lever rotation sensors, and sensors for the total compression force of two springs on each lever. With such a design of the support leg, balancing consists of: design "weight distribution" - distribution of the masses of the robot equipment, selection of lever lengths, selection of spring characteristics, determination of their installation locations on the levers, and debug "fine" adjustment of lever lengths, spring installation locations, and their initial compression for all support legs of the diagnostic robot assembled with all equipment, which is installed horizontally on a process stand, achieving horizontality and straightness of the robot axis composed of the axes of the bases and the central part of the transport module.

[0018] This balancing procedure allows to level out the inevitable errors between the values ​​of masses and coordinates of the centers of mass of the robot components used in the calculations and their real values, and the presence of a calculation model of the robot allows to facilitate balancing, since the “sensitivity of the object” to changes in the balancing parameters can be determined in advance.

[0019] Thus, the use of balancing weights is excluded, and it can also be said that the wheel support of the transport module acquires the quality of adaptability to inaccuracies in the description of a specific design implementation of an in-pipe diagnostic robot and ensures balancing of the transport module even, for example, when changing diagnostic equipment or changing the type and / or number of batteries during the operation of the robot, which expands its functionality.

[0020] The problem of facilitating the overcoming of obstacles is solved by constructing a control loop for the drive for retracting or extending the movable part with wheels relative to the fixed body of the support leg based on the readings of the sensor for the deflection of the lever with the drive wheel, the sensors for the compression force of the springs and the sensors for the current of the motor wheels, and the readings of the sensors of all the support legs of the transport module can be used for the analysis and generation of control commands.

[0021] The task of increasing the energy efficiency of the transport module is solved by eliminating the “parasitic” weight of the balancing weights and, accordingly, eliminating additional energy costs for moving the additional (to the design) weight of the robot, as well as eliminating the costs of “dynamic” balancing of the robot due to additional work of the wheel drives. Positive effects of the invention

[0022] The technical result of the proposed invention is the ability to adapt the support of the transport module when balancing the robot, giving it static stability, reducing the load on the support wheel and improving its adhesion to the inner surface of the pipe. Description of drawings

[0023] The essence of the invention is explained by the following drawings and figures. Figure 1

[0024] illustrates the adaptive wheel support of the transport module, side view. Figure 2

[0025] illustrates the B-B section of the adaptive wheel support of the transport module. Figure 3

[0026] illustrates the adaptive wheel support of the transport module, bottom view. Implementation of the invention

[0027] The adaptive wheel support of the transport module of the in-pipe diagnostic robot, which contains a central link and two supporting bases connected to it by two-axis hinges, is one of three support legs mounted on each supporting base and directed radially at an angle of 120° and consists of a fixed body 1 and a movable section 2 with a wheel mover mounted at its end. Each support leg is telescopically extended or retracted by means of its electric drive 3 with a self-braking screw mechanism 4. The wheel mover consists of two independent drive motor wheels 5-1 and 5-2, each of which is mounted at the end of its rod 6-1, 6-2, installed in sleeves 7-1, 7-2 of a two-beam telescopic lever, the identical beams of which are made in the form of two-section telescopic arrows. The brackets 8-1, 8-2 installed on the sleeves fix the selected extension length of the lever rods L1, L2.Each lever is connected to the movable section 2 by the second ends of the sleeves 7-1, 7-2 by means of cylindrical hinges 9-1, 9-2, the axes of which are directed perpendicularly to the longitudinal axis of the robot. The levers are spring-loaded relative to the movable section 2 by means of two identical compression springs 10-1, 10-2 for wheel 5-1 and 11-1, 11-2 for wheel 5-2, respectively. Each spring on each lever is installed (put on) with its ends on a pair of opposing upper and lower conical stops 12-1, 12-2, 13-1, 13-2 (see arrangement diagram A-A on) and 14-1, 14-2, 15-1, 15-2 (see), respectively. The lower stops 12-2, 13-2, 14-2 and 15-2 are placed on the lower mounting strips 16, which are installed in the required position along the length l1, l2 on the lever rods and are fixed with two clamping brackets 17, as shown for wheel 5-2.The upper stops 12-1, 13-1, 14-1 and 15-1 are placed on the upper strips 18, which are connected to the movable plates 19 by means of two guides 20, limiting any displacement of the strips 18 relative to the plate 19, except for movement along the axis, wherein the strips 18 transmit the compression force from the springs 11 to the force sensor 21, mounted on the plate 19, through the adjusting screw 22. The plate 19 is mounted on the bracket 23, which is secured to the movable section 2. The arrangement of the spring suspension elements for the wheel 5-1 is similar to the wheel 5-2 and is not shown in detail. The compression of the springs is limited by adjusting the gap δ between the opposing paired conical stops 12, 13, 14, 15 by means of the adjusting screws 24, and the measurement of the angles of rotation of the levers is carried out by means of a pair of sensors 25.The motor wheels are made with tires that are given a toroidal shape with a tread, with a contact surface whose radius is smaller than the inner radius of the pipe and made of a material with a high coefficient of friction, for example, by casting rubber or polyurethane.

[0028] The adaptive wheel support of the transport module of the in-pipe diagnostic robot functions as follows.

[0029] At the design stage, the robot equipment mass distribution is performed, the spring parameters are selected - diameter, length and rigidity, the lengths of the levers L1, L2 are determined, the location of the lower mounting strips 16 on the rods 6-1, 6-2 at distances l1, l2 from the axes of the hinges 9-1, 9-2 are set, the gaps δ between the mounting cones are set. After assembling the diagnostic robot and installing it on the horizontal stand by adjusting the lengths of the levers by moving the rods in the lever sleeves, the locations of the springs by shifting the strips 16 and their initial compression using the adjusting screws 22 for all the support legs of the assembled diagnostic robot, the horizontality and straightness of the robot axis made up of the axes of the supporting bases and the central part of the transport module with the hinges between them unlocked are achieved. After finishing the balancing, the obtained parameters of the support are fixed using the clamping clamps 8-1, 8-2, the pressure clamps 17 and the lock nut on the screw 22.

Claims

An adaptive wheel support for a transport module of an in-pipe diagnostic robot, which comprises a central link and two supporting bases connected to it by two-axis hinges, which is one of three support legs mounted on each supporting base, directed radially at an angle of 120°, with independent drive wheel movers and consisting of a fixed body and a movable section with a wheel mover mounted on its end, which telescopically extends or retracts using its independent electric drive with a self-braking screw mechanism, characterized in that the wheel mover consists of two independent drive motor wheels, each of which is mounted on the end of its lever, the second end of which is mounted on the movable section of the support leg using a cylindrical hinge and is spring-loaded relative to it using two identical compression springs, symmetrically located relative to the longitudinal axis of the lever,wherein the axis of the cylindrical hinge is directed perpendicular to the longitudinal axis of the robot, and the levers are configured to change the length of each lever, change the position of the attachment point of each pair of springs on its lever and change the amount of initial compression of each spring, and spring compression limiters are installed, while sensors are installed on each support that monitor the movement of the movable section relative to the fixed support body, lever rotation sensors and sensors of the total compression force of two springs on each lever, wherein each lever is designed as a two-section telescopic boom, the fixed section of which - a sleeve is connected by a hinge to the movable section of the leg support, and a movable section - a rod is placed in the sleeve, at the end of which a motor wheel is installed, and lower mounting strips with lower mounting cones are fixed in a given position, upper mounting cones are fixed on the upper bar,wherein springs are placed on the upper and lower mounting cones so that their lower ends rest on the lower mounting strips, and their upper ends rest on the upper strips, wherein the upper strip is in turn connected by means of two linear guides to a movable plate mounted on a bracket secured to the movable section of the support, wherein an adjusting screw coaxial with the linear guides and the spring compression line is mounted on the upper strip, which rests against a spring compression force sensor mounted on the movable plate, and the spring compression limitation is ensured by adjusting the gap between the opposing paired conical stops using adjusting screws on one of the paired mounting cones, wherein the motor wheels are made with toroidal tires with a tread, with a contact surface radius that is less than the inner radius of the pipe, and are made of a material with a high coefficient of friction.

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