Improved robotic inline pipe inspection system and apparatus

Abstract

SOLUTION: To provide an autonomous robotic active gas-transporting pipeline test system, including: a remotely controlled robot assembly that is movable inside a stream of gas flowing within a pipeline, wherein the gas flow exhibits dynamic flow energy; a small-sized rotary turbin reacting to the gas flow; an electricity generator reacting to the turbin; a battery reacting to the electricity generator; and drive traction means reacting to the electricity generator, for moving the assembly.EFFECT: A system can extract the dynamic flow energy in order to either or both charge a battery or / and operate the drive traction means.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This application relates to remote controlled robots for the inspection of interior walls of natural gas pipelines and the like. [Background technology]

[0002]

[0002] Remotely controlled robots for the inspection of interior walls of natural gas pipelines and the like utilize one or more batteries whose finite battery life necessitates periodic recharging. The robot assembly or a portion of the robot assembly must be removed or accessed, thereby requiring opening a portion of the gas pipeline to access the battery.

[0003] In this regard, until the invention was made by the undersigned inventors, this fact has prevented such robots from being used more widely and more efficiently: the downtime required to recharge the batteries more frequently leads to a loss of inspection time and efficiency. Summary of the Invention [Problem to be solved by the invention]

[0004] In natural gas pipelines and the like, gas or fluid flowing through the pipe carries with it natural kinetic energy. The objective of the present invention is to extract such kinetic energy associated with the gas flow and use it to move the entire robotic assembly and / or charge a battery. This objective is achieved by at least one pressure drop reaction turbine that requires a relatively small psi pressure difference to autonomously drive an associated generator. No removal or access to the robot battery is required for any relatively significant practical time. Moreover, it is achieved fully autonomously. [Means for solving the problem]

[0005] Another object and / or feature of the present invention is to provide what will be referred to herein as a deployable-foldable barrier that can autonomously control the pressure drop across the barrier. The barrier tip is automatically and autonomously adjustable so that the barrier tip can contact the interior pipe wall in a substantially resistance-free manner or increase the gap between the barrier tip and the interior pipe wall. The battery, barrier, energy extraction turbine, and associated generator function in conjunction with one another to extract kinetic gas flow energy and use the extracted energy to drive a robot using towing force within the pipe and / or to charge the battery, if necessary. The present invention can use the extracted gas flow energy to drive a robotic assembly without the need to draw energy from a battery.

[0006]

[0006] Additional features and objects of the present invention include providing novel automatic, computer-driven feature recognition capabilities, including, among other things, inner pipe obstruction detection, bend detection, T-junction detection, and the presence of other predetermined and non-predetermined features.

[0007] The scope of the present invention contemplates the subject technology for use in inspecting pipes transporting natural gas and other gases as well as other fluids and possibly liquids. It is also contemplated that one or more types of sensing means, such as a camera, may be utilized.

[0008] It is expected that the reader of this patent specification will recognize that one of the purposes and goals of the present invention is to provide a new and improved system and apparatus for reducing the operational complexity associated with prior art means for using robots for in-line inspection of pipes of any kind, including but not limited to pipes for the delivery of natural gas. This is accomplished using a novel method and apparatus in accordance with the present invention.

[0009]

[0009] Among the goals achieved using the present invention are to increase robot range, reduce deployment costs, reduce the need for on-site personnel, improve the quality of the evaluation pipeline data that is available, and increase the robustness of the robots used.

[0010] Additionally, the present invention, in a preferred, though not required, embodiment, incorporates the use of energy extraction subsystems and devices to enable enhanced wireless communications over longer distances.

[0011] Among other inventions disclosed herein, the present invention teaches a novel and new robotic in-line inspection system and apparatus for "no-pig clean" natural gas pipeline inspection of various sizes, merely by way of example. Preferably, but not necessarily for the purposes of this application, we focus on pipe diameters from 6 inches to 36 inches without departing from the scope and spirit of the present invention.

[0012]

[0012] The present invention represents the latest in the ongoing evolution of the development of robots that can be successfully implemented in this environment, and the significant efforts in this regard of, for example, InvoDane Engineering and the Northeast Gas Association should be acknowledged here.

[0013] While the inventors choose to use the term "non-piggable" herein, it is recognized that this term and its use is not uncontroversial. The Pipeline Research Council International (PRCI) has decided not to approve its use. Suffice it to say, the present invention is fully capable of functioning in aging pipelines that are not designed for in-line inspection and therefore have one or more types of problems or unknown factors. Such older pipelines are subject to erosion and corrosion in many places.

[0014] The present invention facilitates providing a safe pipeline integrity management system for use with non-piggable pipelines, the very characteristics of which present challenges, including difficult access and recurring damage mechanisms. This is accomplished without requiring any changes to the pipeline configuration. The system inherently provides safe and easy robot launch and seamless execution.

[0015] The present invention provides a long-range robot that can reside within a pipe for longer distances than known in the art and can travel greater distances with less operator control or input, thereby enabling better collection of high-value pipeline information.

[0016] A significantly preferred embodiment of the present invention involves providing what is referred to herein as an energy extraction system, which allows a robot to extract, for example, natural gas flow in a pipeline for both towing the robot and charging the robot. While natural gas is presented as an example of this stream, the present invention contemplates using this energy extraction with any number of gases and / or fluids without departing from the scope or spirit of the present invention.

[0017] Additionally, the present invention teaches placing robots in the pipeline that can be preprogrammed to endpoints to increase the amount of time the robot is in the pipeline, allowing for increased inspection distances, reduced mining, and reduced labor costs.

[0018] Another significant feature and focus of the present invention is the realization of expanded autonomous operation of robots. This allows for a reduction in the "piloting" role of highly trained personnel, which is known to lead to inconsistent and inefficient control of the robot. This feature also allows for the reduction or elimination of full robot supervision and wireless communication bandwidth. Furthermore, the time and effort required for training and maintaining a "large" number of trained personnel is substantially reduced or eliminated.

[0019]

[0019] Furthermore, the present invention contemplates providing computer automation, feature recognition, driving assistance, pipeline mapping, and overall system testing and evaluation. [Brief explanation of the drawings]

[0020] [Figure 1]

[0020] FIG. 1 is a side view showing a robot system according to the present invention. [Figure 2]

[0021] FIG. 10 is another diagram showing the robotic system, with the turbine, generator, and barrier labeled. [Figure 3]

[0022] FIG. 3A is a perspective view of a generator turbine and barrier according to the present invention.

[0023] FIG. 3B is a cross-sectional end view showing the components of FIG. 3A. [Figure 4]

[0024] FIG. 1 is a schematic diagram showing components of the present invention. [Figure 5]

[0025] FIG. 5 is a similar schematic diagram to FIG. 4. [Figure 6]

[0026] FIG. 1 illustrates a robot drive wheel and its deployment. [Figure 7]

[0027] 1A-1D illustrate a collapsible barrier according to the present invention shown in both a collapsed and an unfolded configuration. [Figure 8]

[0028] FIG. 1 is a perspective view showing the regulator and turbine outlet of the robotic system. [Figure 9]

[0029] 1A-1C show modules of the present invention in folded and unfolded configurations illustrating the modular design of the present invention. [Figure 10]

[0030] FIG. 1 illustrates a damper plate of the present invention shown in relation to gas flow in a piping installation transporting natural gas. [Figure 11]

[0031] 11 is an alternative view of the damper plate of FIG. 10. FIG. [Figure 12]

[0032] 1 illustrates a pressure regulator structure of the present invention. [Figure 13]

[0033] FIG. 2 is a perspective view showing a pressure regulator mechanism of the present invention. [Figure 14]

[0034] FIG. 14 is a cross-sectional side elevation view of the regulator mechanism of FIG. 13. [Figure 15]

[0035] 2 is a schematic diagram illustrating the operation of a pressure regulator valve of a preferred embodiment of the present invention. [Figure 16]

[0036] 1 is a three-dimensional perspective view of a turbine module according to the present invention; [Figure 17]

[0037] FIG. 17 is a side cross-sectional view showing the module of FIG. 16. [Figure 18]

[0038] 1 is an assembly diagram showing a folded and unfolded barrier module according to the present invention. FIG. [Figure 19]

[0039] 1 is a perspective view showing a 3D stereo camera according to the present invention. [Figure 20]

[0040] 20 is a disparity map showing what the camera of FIG. 19 sees inside the gas transport gas pipe. [Figure 21]

[0041] FIG. 1 illustrates the establishment of noise thresholds according to the present invention. [Figure 22]

[0042] 1 illustrates the pipe bend detection facilitated by the present invention as a robot moves through a gas pipe. FIG. [Figure 23]

[0043] FIG. 1 illustrates the capabilities of the robotic system of the present invention for detecting and inspecting pipe tees. [Figure 24]

[0044] FIG. 1 illustrates a pipeline mapping output made possible by the present invention. [Figure 25]

[0045] FIG. 1 illustrates the GPS positioning capabilities of the present invention. [Figure 26]

[0046] FIG. 10 illustrates the nature of how gravity vector measurements can be used to locate the position of the robotic system of the present invention. [Figure 27]

[0047] FIG. 1 illustrates the installation of an IMU unit as part of a robotic system of the present invention. [Figure 28]

[0048] FIG. 1 is a schematic diagram showing an overview of the pipeline used with gyrocompassing. [Figure 29]

[0049] 1 is a cross-sectional elevation view of a plug valve according to the present invention. FIG. [Figure 30]

[0050] 1 illustrates a robot plug configuration according to the present invention. FIG. [Figure 31] 1 illustrates a robot plug configuration according to the present invention. FIG. [Figure 32] 1 illustrates a robot plug configuration according to the present invention. FIG. [Figure 33] 1 illustrates a robot plug configuration according to the present invention. FIG. [Figure 34]

[0051] 1 is a perspective view of a drive module according to the present invention; [Figure 35]

[0052] 1 shows a drive truck with wheels according to the invention; [Figure 36]

[0053] FIG. 1 shows an odometer wheel on a drive truck in accordance with the present invention. [Figure 37]

[0054] FIG. 10 is a schematic side view showing an actuator pressing the drive track against the inner pipe wall. [Figure 38]

[0055] 1 is a schematic diagram showing a drive wheel, hub, and tire according to the present invention. [Figure 39]

[0056] FIG. 1 shows the distribution of batteries of the present invention. [Figure 40]

[0057] FIG. 1 is an exploded view showing the robot components of the present invention. [Figure 41] FIG. 1 is an exploded view showing the robot components of the present invention. [Figure 42] FIG. 1 is an exploded view showing the robot components of the present invention. [Figure 43] FIG. 1 is an exploded view showing the robot components of the present invention. [Figure 44] FIG. 1 is an exploded view showing the robot components of the present invention. [Figure 45]

[0058] FIG. 1 is a perspective view showing an assembled robotic system according to the present invention. [Figure 46]

[0059] FIG. 1 illustrates the pipe cleaning component of the robotic system in relation to the pipeline to be cleaned. [Figure 47] FIG. 1 illustrates the pipe cleaning component of the robotic system in relation to the pipeline to be cleaned. [Figure 48] FIG. 1 illustrates the pipe cleaning component of the robotic system in relation to the pipeline to be cleaned. [Figure 49] FIG. 1 illustrates the pipe cleaning component of the robotic system in relation to the pipeline to be cleaned. [Figure 50] FIG. 1 illustrates the pipe cleaning component of the robotic system in relation to the pipeline to be cleaned. [Figure 51] FIG. 1 illustrates the pipe cleaning component of the robotic system in relation to the pipeline to be cleaned. [Figure 52]

[0060] FIG. 52 shows wire brush and sanding components used in the pipe cleaning module of FIGS. 46-51. [Figure 53] FIG. 52 shows wire brush and sanding components used in the pipe cleaning module of FIGS. 46-51. [Figure 54] FIG. 52 shows wire brush and sanding components used in the pipe cleaning module of FIGS. 46-51. [Figure 55] FIG. 52 shows wire brush and sanding components used in the pipe cleaning module of FIGS. 46-51. [Figure 56] FIG. 52 shows wire brush and sanding components used in the pipe cleaning module of FIGS. 46-51. [Figure 57] FIG. 52 shows wire brush and sanding components used in the pipe cleaning module of FIGS. 46-51. [Figure 58] FIG. 52 shows wire brush and sanding components used in the pipe cleaning module of FIGS. 46-51. [Figure 59] FIG. 52 shows wire brush and sanding components used in the pipe cleaning module of FIGS. 46-51. [Figure 60]

[0061] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 61] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 62] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 63] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 64] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 65] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 66] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 67] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 68] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 69] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 70] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 71] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 72] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 73] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 74] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 75] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 76] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 77] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 78]FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 79] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 80] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 81] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 82] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 83] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. [Figure 84] FIG. 1 illustrates a pipeline cleaning device that may be incorporated into a robotic system according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0021]

[0062] Energy Extraction Structure:

[0063] One of the primary objectives of the present invention is to provide a robot with a module having energy extraction capabilities. As used herein, the term "energy extraction" is intended to include the extraction of energy from the very gas flow in the pipeline to be inspected. Such a module is designed to be integrated into the robot, allowing the robot to operate in pipelines with internal diameters of, for example, but not limited to, 20 inches and 26 inches.

[0022]

[0064] This approach relies in part on creating a pressure differential across the robot. To create this pressure differential, the robot has the ability to restrict and regulate the gas flow around the robot. Increasing this pressure differential generates a traction force in the direction of the flow, as shown in (Error!). As the robot moves in the direction of the gas flow, the traction force reduces the power consumption of the drive module. To further reduce battery consumption and enable the gas flow to be used to charge the robot battery, it becomes necessary to generate electrical power. This is facilitated by the addition of a turbine attached to the generator, as shown in Figure 2.

[0023]

[0065] Target Requirements: Table 1 below specifies the target requirements and expected operating ranges.

[0066] Table 1: [Table 1]

[0024]

[0067] The energy extraction module is essentially a drive module with the following structural components added to it: (a) a mechanism (barrier) for restricting flow in order to increase the pressure difference; (b) a mechanism for safely regulating the pressure difference; and (c) a mechanism (turbine) for generating electrical power from the gas flow.

[0025]

[0068] Additionally, the energy extraction module is designed to (a) keep track of the robot's movement speed in all operating modes, (b) incorporate additional safety devices, (c) increase drive force to compensate for the additional weight, (d) exhibit high reliability and ease of maintenance and servicing, and (e) minimize operational impacts by not requiring folding, thereby eliminating the need to fold the energy extraction module, for example, when the MFL sensing section can traverse curved sections.

[0026]

[0069] Energy Extraction Module Design: The present invention contemplates a custom drive module that can accommodate the mechanisms needed for energy extraction. Figures 3A and 3B show an embodiment of such a module. A system added to the drive module provides a barrier that can be expanded to increase flow obstruction or retracted to reduce flow obstruction. A turbine module is attached to one side of the energy extraction module for electrical power generation, and a pressure regulator module is attached to the other side to fine-tune the pressure differential and even relieve overpressure.

[0027]

[0070] In what is described herein as the Phase I approach, embodiments of the present invention provide a barrier system for coarse regulation of pressure differential and power, an electrical load for fine regulation of power, and a passive pressure relief system for transient management. Optimization provides compactness to allow for modular integration into modular robots. In the Phase II approach, system optimization allows for refinement of the control approach.

[0028]

[0071] More specifically, in the Phase I approach, pressure differential control is achieved using a barrier, which is relatively slow to actuate and is not particularly precise, particularly linear, or particularly constant in its adjustment. None.

[0029]

[0072] For coarse regulation of the pressure differential, an adjustable pressure regulator valve is used. When the pressure regulator is operating at the limit of its flow capacity, the barrier position is adjusted to create more favorable flow conditions for the regulator.

[0030]

[0073] Additionally, the pressure regulator acts as a passive pressure relief device for flow transients. Additionally, the pressure regulator acts as a passive pressure relief device for flow transients. Furthermore, if the pressure differential exceeds a set point, it will increase the opening area until the pressure differential returns to the set point.

[0031]

[0074] In power conditioning, only the power needed is taken from the generator instead of discarding excess power as heat, which serves to significantly reduce the size of the shunt, as well as reduce mechanical and thermal stresses on the generator.

[0032]

[0075] Speed ​​management is achieved via a "cruise control" system that monitors the robot's set speed. Using speed management, if the robot is moving too slowly, the control loop will increase the pressure differential, thereby increasing the traction force. Conversely, if the robot is moving too quickly, the pressure differential will decrease, thereby decreasing the traction force.

[0033]

[0076] Figure 4 shows the Phase I control approach from Phase I, whereas Figure 5 shows the modified Phase II approach.

[0034]

[0077] In the Phase I approach, barriers were used to roughly control the pressure differential and resulting power output. Large resistor banks (shunts) dissipate excess electrical power to help regulate the power down to the level required by the robot.

[0035]

[0078] In the Phase II approach, pressure regulator valves are used to fine-tune the pressure differential instead of a barrier, and power regulation is achieved primarily by taking only what is needed from the generator, thereby allowing the size of the flow divider to be reduced.

[0036]

[0079] Modular drive unit:

[0080] The driver portion of the module is designed to accommodate 24 inch to 26 inch pipe. The deployment force is designed to compensate for the weight of the additional module. Figure 6 shows a cross-sectional view of the drive track deployment mechanism according to the present invention.

[0037]

[0081] In Figure 7 the complete energy extraction module presented by the present invention can be seen in both folded and deployed modes (drive track and barrier). Figure 8 shows a "front" view of the module, depicting the flow outlets for the turbine and the pressure regulator valve.

[0038]

[0082] To allow for easy maintenance and servicing, the energy extraction modules themselves are designed to be modular in nature: the turbine module, pressure regulator module, and barrier module can be replaced for maintenance and servicing or adapted to fit various pipeline diameters (see Figure 9).

[0039]

[0083] The modules are designed with connectors that automatically establish electrical connections when the modules are installed. This makes it easier to manage connectors and cables during maintenance and servicing. This eliminates the need for wires and significantly reduces the risk of damaging wires or losing connectors.

[0040]

[0084] Regulator Module:

[0085] A regulator module is designed to control and limit the pressure differential across the energy extraction module. The area differential across the damper relative to the pivot point (see Figure 10) is balanced with a torque applied to the pivot point to determine the valve opening area. A pressure differential greater than the set point will cause the valve to open further, while a pressure less than the set point will cause the valve to close. The mechanism is designed to operate from 3.4 kPa (0.5 psi) to 17 kPa (2.5 psi). If the pressure at the inlet exceeds the set point, the damper plate rotates, allowing this increased pressure to escape.

[0041]

[0086] Previous design efforts covering the pressure regulator portion, shown in Figure 11 (side view) and Figure 12 (3D view), were based on having a damper with a constant force spring. These design efforts were replaced after it was discovered that this mechanism was overly susceptible to friction and had a tendency to stick.

[0042]

[0087] The pressure regulator mechanism in its current design uses a motor instead of a spring with a sliding arm to fine-tune the amount of bypass. This mechanism (shown in Figures 13 and 14) is beneficially simpler, with fewer moving parts. It is also able to fit into the same solution space as the previous design. Power is required to hold the damper plate in place, meaning that during a power outage, a fail-safe state is entered, with the flow pushing the damper plate into the open position. This power consumption slightly reduces the energy extraction efficiency, at approximately 0.6 W at the minimum pressure differential target and 15 W at the maximum pressure differential target. However, this efficiency loss is considered negligible compared to the overall power generated.

[0088] FIG. 15 illustrates the operation of the pressure regulator valve of the preferred embodiment.

[0043]

[0089] Turbine Module:

[0090] A turbine module according to the present invention is shown in Figure 16 and consists of a turbine and a generator interconnected by a shaft and supported by ball bearings. The turbine consists of a set of fixed and rotating blades with an inlet cowling and a diffuser outlet. When the turbine module is mounted onto the robot's energy extraction module, electrical connections are automatically made. Figure 17 is a cross-sectional view of the turbine module.

[0044]

[0091] Barrier Module:

[0092] The purpose of the barrier module is to restrict flow that bypasses the module, thereby increasing flow through the turbine. The module consists of two halves, each with a motor that drives a set of petals. The petals include a flexible outer seal that changes shape to contact the pipe surface and a rigid section attached to an actuation gearbox. As the motor rotates, gears simultaneously transfer this motion to the actuation gearbox, thereby rotating the petals from a folded position to an extended position, as shown in Figure 18.

[0045]

[0093] Computer Automation:

[0094] It is recognized that robotic automation requires relatively complex data processing. With this in mind, the present invention provides an on-board robot "main" computer that allows for increased processing power to enable automation.

[0046]

[0095] Proprietary electronics are interconnected between the automation computer and what is referred to herein as the robot power and communication bus. The computer, along with its associated active heat sink, is supported by the control module.

[0047]

[0096] The automation computer system according to the present invention can process video signals and data from stereo cameras as well as from robot sensors. With regard to the stereo cameras, the reader is referred to the following discussion directed to feature recognition. With regard to the robot sensors, these sensors make it possible to sense signals from, for example but not limited to, joint angles and wheel speeds. The automation computer further makes it possible to direct the robot (as a whole) through a number of features and capabilities referenced later in connection with the assisted drive.

[0048]

[0097] Feature Recognition:

[0098] Feature recognition is a highly desirable feature in robots of the type contemplated by the present invention. Prior art robotic camera systems are unable to provide the significantly high quality and accurate output required for effective feature recognition.

[0049]

[0099] The present invention provides a three-dimensional (3D) stereo camera supported on the control module and positioned slightly off-center from the longitudinal axis of the robot (see FIG. 19).

[0050]

[0100] In a preferred embodiment, the stereo camera of the present invention acquires two independent images from camera sensors separated by 50 mm. An intensity map is generated from the calculation, in which these two images are compared to each other pixel by pixel. The intensity map also provides a disparity that can indicate the apparent motion of each pixel associated with the two images. In environments with low contrast, such as within a pipeline, an infrared (IR) pattern that is invisible to the human eye is projected by the stereo camera.

[0051]

[0101] By knowing the geometry of the camera sensor and thus the field of view of the camera lens, the disparity map produced is itself converted into a three-dimensional cloud or 3D representation of the pipeline being photographed. Figure 20 shows the disparity map on the left and the point cloud on the right for the scan of a 90 degree bend in the pipeline as the robot approaches the bend.

[0052]

[0102] The present invention contemplates a feature detection algorithm that can utilize the point clouds mentioned above as a source of input data, where a time-space type filter is utilized to minimize or eliminate point cloud noise before use in the processing steps.

[0053]

[0103] Pipeline detection:

[0104] The first step in obtaining feature detection data is to determine the orientation of the robot camera relative to the pipeline geometry. This is achieved by performing and utilizing overhead and side view projections. The pipe ends are located. Later, the point cloud mentioned above is rotated to remove camera pitch from the pipeline representation, so that it is more coaxial with the pipeline in comparison. This allows for an accuracy of approximately 1 degree.

[0054]

[0105] Once the point cloud is coaxially aligned with the pipeline, a series of projections allows the calculation of the minimum and maximum pipe diameters. This alignment also allows the calculation of any ellipticity of the pipeline. In the final step, the aligned To fit the pipeline to the circle T, an axial projection is performed.

[0055]

[0106] Obstacle Detection:

[0107] The present invention includes a novel capability and method for detecting obstacles within a pipeline. This is accomplished by utilizing the point cloud described above. The obstacle detection method preferably begins by fitting a circle to the axial projection of the point cloud. Instead of plotting using Cartesian coordinates, a polar transformation is initiated by truncating the circle at its apex and widening it. See the left side of Figure 21. A noise threshold is established such that any protrusions extending beyond the threshold are classified as obstacles. See the right side of Figure 21.

[0056]

[0108] Curvature detection:

[0109] Detecting pipeline bends is relatively complex because it requires not only detecting the presence of a bend, but also establishing an accurate bend plane and center path for the purpose of accurately aligning the robot.

[0057]

[0110] Once both the presence of a bend and the bend plane have been determined, a center point must be established through measurements. The point cloud referenced above is rotated until the bend is shown horizontally (0 degrees) and an overhead projection is performed. The present invention utilizes a line-tracking image processing algorithm to detect the outer edge of the pipe, and a known radius is projected inward. A three-dimensional center point is generated, which is necessary for navigation. To enable navigation, the two-dimensional point is rotated in three-dimensional space using the angle found in the previous step. See Figure 22.

[0058]

[0111] Tee detection:

[0112] A robotic pipeline inspection according to the present invention involves manipulating a pipeline tee. The tee inspection begins with an axially aligned point cloud. This cloud is cut and widened, as seen in the upper left of Figure 23. A hole in the point cloud is identified and sized, as shown in the lower left of Figure 23.

[0059]

[0113] Assisted driving:

[0114] The present invention incorporates what is referred to herein as an assisted drive method and apparatus. Novel improvements to existing drive assistance software are incorporated based on real-world conditions. This includes the use of software control means, as well as a novel navigation control module, as described below.

[0060]

[0115] The drive support software according to the present invention can be controlled by signals or messages sent from either a local controller or a remote controller. The drive support software is compiled to run on the automation computer referenced above.

[0061]

[0116] The navigation module controls the robot via the drive assistance described above with feedback from the robot sensors and feature recognition module. The navigation module is a rule-based generic mechanism for controlling the robot. The navigation module can run on a desktop or laptop computer, can control an Explorer simulator, or can run on an automation computer of the type described above.

[0062]

[0117] The goal of this invention is to provide a navigation system that allows for significantly simpler control than conventional systems. The goal of this invention is to provide a robotic motion module that automatically detects and reacts to the robot's speed. Instead of actuating individual joints, adjusting the throttle, or watching video to identify and react to approaching features, the invention allows the user to input a desired speed. The software of the invention autonomously ensures that it is safe to move forward by verifying that all feedback from the robot and feature recognition modules is correct.

[0063]

[0118] If the robot feedback is deemed unreliable or in any way untoward (by way of example only, if the throttle is too high for the current velocity setpoint, or if the joints are deployed too far from the current radius, etc.), the software of the present invention will stop the robot and await further commands from the operator.

[0064]

[0119] When features are detected by the feature recognition module, the navigation module can react to them appropriately. In cases where features do not require user input (e.g., in a curve), the software will ensure that the robot is accurately aligned with the plane of the curve and will navigate through the curve by tracking its 3D center point.

[0065]

[0120] There are features that require a user decision, such as when a tee is encountered, in which case the software of the present invention will stop the robot until another command is received.

[0066]

[0121] Unsafe conditions can be detected by the feature recognition capabilities of the present invention. Such conditions may include, by way of example only, the presence of a relatively large obstacle or blockage, or the absence of a recognizable pipeline. In such instances, control is communicated to a user of the system.

[0067]

[0122] Pipeline Mapping:

[0123] A pipeline mapping capability is provided by the present invention. This is achieved, at least in part, by providing an inertial measurement unit (IMU) supported by the robot. Techniques are provided for post-processing the IMU data using survey data for accurate mapping.

[0068]

[0124] Data is collected from the IMU at a relatively high rate (e.g., 1 kHz). Electronics supported by the robot communicate over a bus, resulting in a record of the data and upload to memory so it can be processed. This processing of IMU data relies on a Kalman filter. Kalman filtering can be defined as an algorithm that can provide an estimate of an unknown variable. In the present invention, the algorithm uses a series of measurements observed over time with a hypothetical statistical nozzle model to produce estimates that tend to be better than making each single measurement. This filter is used to predict next states, such as position, velocity, orientation, and scale and bias of the various IMU measurements. These predictions are updated as new data becomes available, such as via a GPS update or odometer.

[0069]

[0125] In real-world pipeline mapping, GPS updates are achieved using above ground markers (AGMs), which are placed above the underground pipeline at predetermined locations. The AGM monitors the magnetic disturbances created by the passage of the inspection tool, which are timed to a precise timestamp that is recorded. Relying on precise timestamps allows both of these to be correlated later. , and GPS updates can be applied to post-process the IMU data.

[0070]

[0126] To mimic real-world applications, during testing GPS updates are limited to frequencies equivalent to those available from the AGM's location, or, for example, every 1000 feet from 500 feet.

[0071]

[0127] An odometer wheel mounted on the test cart simulates the odometer available on prior art pipeline inspection robots. Continuous 10Hz updates with an accuracy of up to 1% are provided. Because the odometer does not provide absolute information, it is fed into the Kalman filter to act as a correction to the estimated velocity.

[0072]

[0128] Because absolute measurements are not taken between GPS updates, and because of the inherent inaccuracy and noise in IMU and odometer readings, the estimated position will become larger over time, as shown in Figure 25. Because IMU processing is not done in real time, future GPS updates are used to help reduce positional errors. To accomplish this, the present invention rotates the IMU / odometer measurements by 180 degrees. The data is filtered in reverse time, from the last sample to the first sample. The filter estimates the change in position in addition to the position. In this way, forward and reverse filter passes can be weighted by the estimated change and optimally combined.

[0073]

[0129] Additional optional accuracy is obtained by utilizing heading error correction. At rest, the IMU detects only the Earth's rotation and acceleration due to gravity. By rotating the gravity vector relative to the Earth's rotation, an estimated circle of latitude is obtained. See Figure 26. Knowing the Earth's rotation direction and the gravity vector, the device's heading (degrees from north) is calculated. The accuracy of this calculation is determined by the duration of the stationary state. For example, from 20 minutes of data, an accuracy of approximately 2% can be achieved. The term "gyrocompassing" is adopted here to indicate its periodic use to correct heading error.

[0074]

[0130] Installation on the robot

[0131] The present invention includes providing a mount supported by the robot to receive the above-mentioned IMU, logging electronics, and a relatively small spare battery located in the battery compartment of the robot's drive module. See Figure 27, which shows the IMU installed on the robot.

[0075]

[0132] Mapping Process

[0133] Essentially, before the robotic inspection begins, the location and orientation of the launch site is surveyed. The robot is deployed and IMU data is recorded. After a predetermined distance, or after a bend, the robot is stopped to allow for gyrocompassing. Ground markers (AGMs) are placed as needed to improve accuracy. Figure 28 shows an attempt to provide an overview of this pipeline in schematic form.

[0076]

[0134] Plug Valve Navigation and Functionality:

[0135] It is known that robots will and must operate in pipeline environments having plug valves capable of stopping or enabling the flow of gas therethrough. Broadly speaking, such plug valves may have a plug formed with a port therethrough secured to a valve stem via one or more attachments to an operating handle. A plug is placed in the gas flow so that, by rotating the valve handle, the port in the plug can stop, allow, or control the flow of gas. Of course, the presence of the plug and its port also creates a small-diameter port obstruction in the robot's desired path. The port diameter or opening is necessarily smaller than the inner diameter of the pipeline into which the plug valve is installed. Figure 29 shows, in partial schematic cross-section, a conventional type of plug valve with an elongated port in its plug, not necessarily for use with gas pipelines.

[0077]

[0136] The present invention provides a robot pluggable module, shown in Figures 30-33, equipped with a plurality of magnet bars arranged to be expandable around a central body. In the initial state shown in Figure 30, the magnet bars are at rest, so that the central body can be positioned relatively close to or at the center of the pipeline that transports the robot. In Figure 31, the magnet bars are folded and occupy approximately 75% of the inner diameter of the pipeline. A latch located at the end of the central body is engaged.

[0078]

[0137] In Figure 32, the latch is released, causing the robot to drive forward, allowing the ramps of the magnet bars slidably mounted on the slide members to extend outward to the front and rear of the module, thereby extending the overall length of the module by approximately 250%.

[0079]

[0138] Figure 32 shows the axial location of the magnet bar at the end of the sliding member so that at this point it can achieve a hinged motion about the end of the central body, thereby reducing the overall diameter of the module so that it can be pulled or moved through a plug port in a plug valve. Figure 33 shows an axial view of the module in its reduced diameter configuration.

[0080]

[0139] Preferred drive system embodiments:

[0140] FIG. 34 shows, in a preferred embodiment of the present invention, a drive module provided for moving a robot through a pipeline measuring, by way of example only, 30 inches to 36 inches in diameter. Traction is provided in both horizontal and vertical sections. The drive module is designed to generate sufficient frictional pressure of its drive wheels against the inside diameter of the pipe to pull a relatively heavy robot.

[0081]

[0141] The drive module preferably has structural components including a main body, an actuator, battery storage, an odometer, automatic connection points, and control circuitry. Each of these is discussed below:

[0082]

[0142] The main body has two drive tracks on either side (one side is shown in Figure 35), which contain two driven wheels (one on each side) that are press-fit with urethane to provide sufficient friction to generate the necessary traction mentioned above.

[0083]

[0143] Actuators deploy the wheels on the pipe wall. The deployment force is adjusted as the robot moves through the pipe to maintain constant friction across a variety of pipeline geometries. The drive module collapses to 75% of the pipeline diameter, down to 57.2 cm (22.5 in).

[0084]

[0144] Battery storage accepts rechargeable battery packs. The battery can be charged or replaced directly on the robot. For battery replacement, a quickly removable cover is provided.

[0085]

[0145] An odometer, one shown in Figure 36, is mounted on each drive truck to measure the distance traveled within the pipe. Each odometer wheel is specifically designed to cut through debris on the pipe wall and to eliminate slippage.

[0086]

[0146] Automatic connection points are located adjacent to the modules to eliminate the need for bulky wire-to-wire connectors.

[0087]

[0147] Control circuitry is provided to enable communication to the robot nose and also to operate all of the actuators that deploy and drive the wheels.

[0088]

[0148] Figure 35 shows the main drive module body supporting the deployment actuator and drive track. The arrows depict the magnitude of relative movement. A moveable linkage connects the drive module center body to the drive wheels.

[0089]

[0149] Figure 36 depicts the odometer wheel on the drive track and further identifies the odometer sensor. The deployment actuator that presses the drive track against the inner pipe wall is shown in Figure 37. The deployment actuator includes a drive motor that is connected to a lead screw via a spur gear. The lead screw is connected to the opposite end of the actuator and provides the appropriate force throughout the stroke. The connection point is cushioned by a spring so that small misalignments in the pipe wall can be absorbed. A deflection sensor monitors the compression of this spring and sends that information back to the operator.

[0090]

[0150] The drive wheel power transmission is shown in Figure 38. A motor is housed centrally between two drive wheels. The motor drives a hollow shaft, which is connected to a transmission. A hub is then connected to another shaft, which transmits torque from the transmission back to the gear / motor combination and through this gear / motor combination to the other side of the assembly. Here, the shaft is connected to another hub. A wheel is then connected to this hub.

[0091]

[0151] This design allows the motor to drive large torques equally on both sides of the drive track.

[0092]

[0152] Robot Battery Power Distribution:

[0153] The present invention contemplates the distribution of batteries within and among multiple modules. This is shown schematically in FIG. 39. To fully utilize the capacity available for energy storage throughout the robot of the present invention, batteries are distributed throughout the robot. This approach decentralizes energy storage on the robot rather than having a central power module. Thus, each module connects to a power bus for the purposes of balancing power throughout the robot and for charging. Each individual power component within each module is configured to provide a constant voltage to the power bus according to the overall robot demand. When the power bus is supplied with energy for charging, each power section conserves this energy by switching to charging mode. This approach allows the robot to be charged without removing batteries and further extends the range of the maximum amount of energy storage required. This also allows the remainder of the robot to function if one module does not provide power or is taken offline for some reason.

[0093]

[0154] Another aspect of the present invention:

[0155] Figures 40 through 44 illustrate schematic diagrams of robots within the scope of the present invention. More specifically, Figures 40-41 generally depict configurations of the robot design of the present invention. Figure 42 illustrates a robot configuration suitable for inspecting pipelines with a diameter of 20.3 cm (8 inches). Figure 43 illustrates a robot configuration suitable for inspecting pipelines with a diameter of 25.4 cm (10 inches) to 35.6 cm (14 inches). Figure 44 illustrates a robot configuration suitable for inspecting pipelines with a diameter of 40.6 cm (16 inches) to 91.4 cm (36 inches).

[0094]

[0156] Conclusion:

[0157] The present specification and the appended claims represent examples and various embodiments of the present invention without compromising or departing from the broad scope and meaning of the present invention. The present invention is not limited to the literal discussion herein and to the examples described herein. Other aspects and equivalents of the present invention will suggest themselves to those skilled in the art, and such other aspects and equivalents of the present invention are also encompassed within the meaning and scope of the present invention.

[0095]

[0158] Hardness Testing System: The present invention includes the following hardness testing capabilities:

[0159] approach:

[0160] As mentioned, robotic testing systems have been tested and are being successfully marketed by Invodane under the name and trademark "Explorer." As elsewhere throughout this patent application, an attempt will be made to present the reader with a description of the present invention without unnecessary reference to the Explorer robotic system. However, in the case of the hardness tester of the present invention, an approach has been taken in which a hardness tester module (HTM) is placed on the Explorer system to allow for the use of as many existing robotic components as possible.

[0096]

[0161] The final HTM configuration adopted is shown in Figure 45. The in-pipe hardness tester module concept requires two units (sub-modules): a surface preparation carriage and a hardness tester carriage. Because the surface preparation tool emits particulates into the gas stream, design efforts were made to keep the two functions substantially isolated from each other. Both units are protected from debris that accumulates when not in use.

[0097]

[0162] The surface preparation cart (error!) was designed with the following features:

[0163] A trolley deployed on the pipe wall that can be retracted to meet Explorer's 75% constraint requirement. The trolley can remain deployed on the pipe wall for the duration of the run depending on line cleanliness, characteristics, etc.

[0098]

[0164] There is a spring loaded scraper at the front portion of the carriage to perform the function of removing loose debris from the selected area (where the test will be performed).

[0099]

[0165] Surface preparation is carried out in two steps: first, using a wire brush to achieve a rough cleaning of the surface, then using a finishing tool (for sanding) to achieve a fine cleaning of the surface.

[0100]

[0166] The wire brush system may be deployed on the pipe wall at a 15 degree incline. The wire brush system may operate in parallel with the scrubbing action.

[0101]

[0167] A camera and light source are included to evaluate the surface of the inner pipe wall after the wire brush cleaning step. The operator can see any bends, seam welds, or any other areas for good hardness readings. Other surface features that may interfere with removal can be visually detected. Camera images are recorded for comparison with the post-surface preparation image.

[0102]

[0168] The surface finishing tool is mounted on a sliding device that operates to control axial motion and pressure to achieve the desired surface finish.

[0103]

[0169] A wall thickness probe or similar device monitors the progress of material removal with the sander.

[0104]

[0170] The hardness test carriage (Figure 47) was designed to include the following features:

[0171] It requires that the dolly be pressed against the wall with a force greater than the 981 N (100 kp) required for a direct Rockwell test (Rockwell B).

[0105]

[0172] A positioning camera is located on the front portion of the dolly. The positioning camera positions the dolly to be directly aligned with the prepared surface. The positioning camera will be tilted slightly forward to assist the operator in locating the prepared surface.

[0106]

[0173] A macro camera with high resolution is used to inspect the entire prepared surface. A series of images is recorded. The field of view should be approximately 12.7 cm (5") and should have the highest possible resolution.

[0107]

[0174] A macro camera and a direct Rockwell measurement instrument are attached to the slide.

[0175] The hardness tester is then engaged and automatically performs 10 consecutive measurements, moving approximately 3 mm between each measurement. Images of the indentation are then automatically taken.

[0108]

[0176] Development: The following is intended to serve both as an overview of the process undertaken to develop the hardness testing module as well as an explanation of the features of the module in accordance with the present invention. See Figures 48-49.

[0109]

[0177] The module is centrally located on the Explorer robot in place of the standard MFL sensing section.

[0110]

[0178] The module can be maneuvered through the pipeline feature and positioned to the side of the pipe wall via an existing module on the robot.

[0111]

[0179] The module includes an actuator for pressing the sensing section against the pipe wall, this actuator is called a clamping actuator.

[0112]

[0180] The module contains a drum that can be actuated parallel to the axis of the pipe (feed actuator) and also rotated (drum roll actuator).

[0113]

[0181] The drum includes a surface preparation feature and an indentation feature (or carriage as described above) that is moved into position to perform hardness measurements.

[0114]

[0182] Hardness Test Drum: The hardness test drum (Figure 50) has five positions containing the following components for performing hardness measurements on pipes:

[0115]

[0183] Wire brush wheel: The wire brush wheel removes loose debris from the pipe wall, which either falls to the bottom of the pipe or is transported away by the gas flow around the module. The axial movement of the wire brush wheel is achieved by a robotic drive module, since the required preparation area exceeds the total feed movement.

[0116]

[0184] Sanding Wheel #1: Similar to wire brushes, the drum contains two sanding wheels. The purpose of the sanding station is to precisely remove up to 0.0254 cm (0.010”) of material from the interior of the pipe, leaving a suitable surface finish for hardness testing. The sanding station is moved axially by a feed actuator. Each sanding wheel is equipped with a camera and depth sensor to monitor the sanding process during operation.

[0117]

[0185] Sanding Wheel #1: The drum preferably contains two sanding wheels, similar to wire brushes. The purpose of the sanding station is to precisely remove up to 0.0254 cm (0.010 in) of material from the interior of the pipe, leaving a surface finish suitable for hardness testing. The sanding station is moved axially by a feed actuator. Each sanding wheel is equipped with a camera and depth sensor to monitor the sanding process during operation.

[0118]

[0186] In addition to the wire brush wheel, a camera and depth sensor are installed to both monitor and measure the height of the pipe surface before and after the wire brush process.

[0119]

[0187] Sanding Wheel #2: Equivalent to Sanding Wheel #1, the Sanding Wheel #2 position can be fitted with abrasive paper of equal or finer grit depending on the test conditions.

[0120]

[0188] Direct Rockwell Indenter: The direct Rockwell indenter performs hardness measurements on the prepared surface in rows parallel to the pipe axis by moving a feed actuator. Additionally, the direct Rockwell indenter is equipped with a secondary camera to take a magnified image of each indentation in the measurement set.

[0121]

[0189] Home Position: Contains the control electronics for all measurement functions. When the module is not taking measurements, the drum is rotated to this position.

[0122]

[0190] Although a scraper is not provided in this specification, the present invention contemplates the optional inclusion of a scraper.

[0123]

[0191] Presentation of the entire system: The following is a more detailed description of the system, including the wire brush, sanding wheel, and indenter:

[0124]

[0192] Wire brush:

[0193] The wire brush position is used to remove any loosely adhered debris from the pipe wall. This wire brush position ensures that the sanding wheel and indenter remain relatively clean in the typically very dirty pipeline environment. The wire brush mounted on the HTM cleans an area approximately 4.45 cm (1.75") wide. The indenter contacts a section of pipe that is approximately 10.2 cm (4") wide. Therefore, three passes of the wire brush (back and forth) are typically required.

[0125]

[0194] The actuation for wire brushing the pipe surface preparation is accomplished by moving the robot. With the wire brush motor engaged, the robot is driven back and forth. The entire module is rotated ±10 degrees to achieve a total wire brushed surface width of 10.8 cm (4.25").

[0126]

[0195] The wire brushes used to remove debris from the pipe walls may be off-the-shelf 4.5 inch diameter stringer bead brushes. They have 0.020" bristles twisted together for aggressive cleaning of steel surfaces. This unit is intended for use on bench grinders, CNC machines, and / or angle grinders. Depending on the application, wheels can be easily exchanged on the modules, provided they are 4.5 inches in diameter. The wheels spin at approximately 1000 RPM, which is generally significantly lower than the 15,000 RPM rating. The wire brush wheel position includes a camera to monitor the initial pipe wall cleaning process. If more passes are required, more passes can be made at the operator's discretion. The dimensions of the wire brushed area are shown in Figure 51. The type of wire brush intended to be used is shown in Figure 52. The wire brush preparation wheel on a drum is shown in Figure 53.

[0127]

[0196] Sanding positions 1 and 2

[0197] As well as the wire brush positions, the drum accommodates two sanding wheel positions. The purpose of the sanding wheels is to remove 0.0254 cm (0.010") of the pipe surface and leave a surface finish conducive to making reproducible measurements. As shown in Figure 54, the length of this zone is significantly smaller than the wire brushed surface. The width of the sanded surface is about 4.45 cm (1.75"), with most of the material removed in the center. The length of this area is about 10.2 cm (4"), which is sufficient to accommodate between 15 and 20 appropriately spaced measurements (at least 10 are required, allowing for repeat measurements in axial distance). Generally, four passes (back and forth) with a 60-grit sanding head are required to remove an adequate amount of material.

[0128]

[0198] The sanding wheel used may be a pre-made 11.4 cm (4.5 inch) angled sanding disc made by layering individual cloth-backed abrasive papers. This standard disc, which can be purchased in a variety of grits ranging from 36 grit up to 120 grit, was selected during the feasibility study. The disc is placed on the drum at an angle so that only a 4.45 cm (1.75 inch) wide area is sanded. Figure 55 shows the sanding wheel on the drum.

[0129]

[0199] Associated with the sanding wheel is a distance sensor (Figure 56) and camera to monitor the progress of sanding. The distance sensor measures the distance between the drum and the surface. With each pass of the sanding wheel, the distance sensor records the relative depth of preparation (see Figure 57). Once the appropriate depth is recorded, the preparation is stopped. This process was tested using an in-pipe sanding motor and sensor (see Figure 58) before being integrated into the current design.

[0130]

[0200] Rockwell indenter:

[0201] A fourth element on the drum houses the indenter unit, which indents the pipe along the surface to be prepared according to the set load conditions. The indentation is made along the center of the prepared zone (see Figure 59). As can also be seen in Figure 59, the contour of the indenter element (red line) matches the zone to be scrubbed by the wire brush as described above.

[0131]

[0202] The Test Standard for Hardness Testers provides the following general guidelines for measurements using the Rockwell method on portable units (from CRTD Vol. 91):

[0132]

[0203] The minimum wall thickness for direct Rockwell is 0.635 cm (0.250 in).

[0133]

[0204] The centre of deformation to the edge of the next dent (or edge of the material) must be at least 2.5 times the diameter of the dent. For mild steel this means that at least 2.5mm should be maintained between the centres of the dents.

[0134]

[0205] For a portable tester to be considered equivalent to laboratory results, the measurements should be within 96% to 102% of the laboratory values.

[0135]

[0206] The coefficient of variation (COV) must not be greater than 0.07. It is calculated to give the ratio of the standard deviation to the mean of 10 measurements.

[0207] The measurement range should not exceed 10% of the mean value.

[0136]

[0208] An indenter unit with an electromagnet is shown in Figure 60. The indenter unit is composed of the following components:

[0209] The minimum wall thickness for direct Rockwell is 0.635 cm (0.250 in).

[0137]

[0210] Electromagnets to hold the assembly on the pipe wall: This proved to be very important in being able to achieve the desired precision.

[0211] Place a 0.159 cm (1 / 16”) diameter tungsten steel ball indenter on the end of the linear actuator.

[0138]

[0212] Linear encoder (1 μm resolution) capable of measuring recesses of 60 to 120 μm.

[0213] Load cell up to 100kgf with 0.1% resolution.

[0139]

[0214] Control circuit board.

[0215] The unit itself is designed to provide the appropriate magnitude of load, constant speed, and dwell time specified for the Rockwell B scale (ASTM E18). The Rockwell B scale was used because it can be directly converted to obtain strength values ​​in CRTD Vol. 57. The loads for this scenario are listed in the table below:

[0140] [Table 2]

[0141]

[0216] The steps taken to obtain direct Rockwell measurements using the indenter unit thus developed are as follows:

[0217] Position the unit and turn on the magnet

[0218] Apply a load of up to 10 (F0) to the indenter and zero the depth reading.

[0219] Apply a load of up to 100 (F1) to the indenter

[0220] The indenter load is removed and returned to (F0). A depth measurement is made to obtain the Rockwell hardness value.

[0142]

[0221] Transverse Magnetic Flux Leakage (TMFL) Leakage):

[0222] Existing sensors on Explorer robots can determine the metal loss profile of a pipe in case of loss. The current Magnetic Flux Leakage (MFL) sensors on Explorer tools magnetize the pipe wall axially. In this configuration, one area of ​​reduced sensitivity is axially aligned anomalies, such as cracks. By rotating the magnetization 90 degrees as shown in Figure 61, detection of axially aligned cracks, also known as transverse magnetic flux leakage (TMFL), can be achieved.

[0143]

[0223] Data from an experiment shown in Figure 62 demonstrates the detectability of a crack using a circumferential magnetic field. North (red) and south (blue) poles are shown straddling a 42% deep defect in a 0.250WT plate. The color plot shown shows the radial Hall sensor readings near the crack, obtained by directly measuring the radial magnetic field vector along the surface of the plate. The crack signature can be clearly seen.

[0144]

[0224] The preferred approach for TMFL sensors is to achieve complete coverage of the pipe circumference in the shortest possible module length. The crack sensor uses two sets of circumferential bars. The proximity of the sensing sections to each other may result in some reduction in field strength, but this is acceptable for crack detection. Tests similar to those in Figure 62 show crack detectability in the area around the edge of the magnet pole.

[0145]

[0225] Electromagnetic Acoustic Transducer (EMAT):

[0226] EMAT (Electromagnetic Acoustic Transducer) implements ultrasonic methods in applications where an acoustic transmission medium, usually gel or water, cannot be used between the transducer and the test object. This is the case for gas pipelines, where applying liquid to the inside of the pipe is undesirable. EMAT requires a magnetic field in the substrate along with a pulse coil that moves the acoustic pulse through the material.

[0146]

[0227] Mounting the EMAT sensor on the Explorer involves establishing a suitable magnetic field to generate an acoustic pulse that travels around the circumference of the pipe. Within this field resides a coil or winding, mounted as close as possible to the pipe wall, thereby transmitting and receiving this electromagnetic pulse. These components and their corresponding electronics must be packaged in a manner appropriate for pipeline conditions. The physical components required for EMAT data acquisition can be summarized as follows:

[0147]

[0228] (1) Magnetic field: A magnetic field is required in conjunction with an electrical winding. The magnetic field is substantially perpendicular to the direction of wave travel. An oblique angle can improve the signal magnitude.

[0229] (2) Transmitter Pulser and Coil: This is a combination system in which high voltage pulses are applied to windings that excite the pipe wall with acoustic pulses. e) The high-voltage pulses used in this system are in the range of 500-600 kHz, depending on the coil geometry. The pulses are high voltage (300 V peak), but the overall duty cycle is low because the voltage is applied in bursts.

[0230] (3) Receiver Coil and Signal Processing: The magnetorestrictive force directly beneath the windings generates an electrical signal as it passes through the solid. The first pulse seen is the direct pulse, which is the pulse that reaches the receiver coil directly as it travels through the pipe. Any response after the direct pulse is typically a reflection from edges encountered within the pipe. These edges may be seam welds, metal loss, or crack features. Data is stored in on-board flash for download to data analysis software.

[0148]

[0231] EMAT Controller: In the case of multiple transmitters, the pulses need to be organized to allow the pulse amplitude to decay before the generation of the next pulse. If more than one pulse travels circumferentially at any given time, the reflected path will have multiple peaks in the received signal. Therefore, the pulses generated by the multiple transmitters, and the receivers used to detect the reflections, need to be precisely scheduled. This is performed by the EMAT controller, which provides the synchronization and scheduling for all transmit / receive units around the pipe.

[0149]

[0232] The transmitter and receiver EMAT components can be arranged around the circumference of the pipe as shown in Figure 64. EMAT detection of cracks is shown in Figure 65.

[0150]

[0233] System Design:

[0234] Crack Sensor: To detect axially aligned cracks in non-piggable pipelines, two different technologies were combined: EMAT (Electromagnetic Acoustic Transducer) and TMFL (Transverse Magnetic Flux Leakage).

[0151]

[0235] A key aspect of the sensing section is that it requires a full-circumference magnetic field around the pipe wall. This required many test setups during development. The sensing section, consisting of 8 to 12 poles, divides the model, resulting in full-circumference coverage of the Hall sensors.

[0152]

[0236] The sensing section concept had a total of 84 individual poles separated into six spiral sections, with each spiral section having 10 poles. These sections were spiraled to allow for complete coverage with the MFL sensor, as shown in FIG. 65. As shown in the exemplary cross section of the spiral sensor in FIG. 66, each pole was actuated up and down from the center of the robot, thereby providing collapsibility. The magnets were turned on and off via a rotating magnetic rotor inserted radially into the bucking bar. FIG. 66 further shows that the direction of the magnetic field within the pipe wall was circumferential.

[0153]

[0237] This configuration was necessary to reduce the traction force characteristic and also increase the magnetic field strength within the pipe wall. The large number of poles allows each pole to be mounted above a feature such as a circumferential weld (where the weld connects the pipe segments together), instead of requiring the entire pole to move as the sensor moves over the feature. This approach is shown in Figure 67. This approach results in a lower peak of the traction force in the sensing section.

[0154]

[0238] During development, the magnetic flux for this configuration was simulated. The magnetic flux is shown in Figure 68. Each pole has an area of ​​appropriate flux magnitude where the Hall sensors will be located. These are shown as red squares in Figure 68. As can be seen in this figure, these sensors The sensors overlap each other axially (vertically) between sections. To implement such a sensor layout, the sensors were grouped into four sensor elements and staggered along each slope as shown in Figure 69. In Figure 69, the sensors are shown in purple overlapping around the entire circumference. The magnetic field direction is shown by the gray arrows.

[0155]

[0239] An EMAT sensor is located at each end of the pole, where the magnetic field disperses in the axial direction (Figure 70). This is necessary to generate circumferential shear waves. The shear wave direction (pink arrows) is circumferential around the pipe. The magnetic field at the poles (gray arrows) disperses outward in the axial direction of the pipe.

[0156]

[0240] The EMAT sensor preferably has three controllers that handle the transmission and sensing functions for the sound waves traveling in the pipe. The transmitter has a pulse control module and a pulse driver module. The pulse control module converts 24V to a high voltage source and also switches the control lines of the pulse driver module. The pulse driver module drives the coil at the desired frequency and duty cycle via the voltage source and control lines. Due to space constraints, the pulse driver module and pulse control module are located at each end of the robot. There are two EMAT transmitters (a control module and a driver module pair) on top of the sensor. The EMAT receiver module has a digital-analog section that amplifies the EMAT signal, filters the EMAT signal, and records the EMAT signal. There are preferably four EMAT receivers on top of the sensor.

[0157]

[0241] The poles can be retracted to the smallest diameter of the robot so that the sensor can be rotated around corners in the pipe and into the hot tap section used for launch and harvesting (see Figure 66). Before moving the poles, the magnets must be turned off. The magnetic field is controlled by using the rotor pair concept shown in Figure 71. The rotor pair has a fixed magnet and a rotating magnet (see Figure 71). When the rotors are facing the same direction, the magnet is on. When one rotor is rotated 180 degrees, there is no magnetic field coming out of the block material.

[0158]

[0242] The magnet pairs are housed within a bucking bar and spiral along the length of the sensing section of Fig. 74. A rotor is actuated from each end, thereby turning the magnets on and off. Additionally, the bucking bar provides a sliding surface for the magnet poles during harvesting and deployment.

[0159]

[0243] The entire system can be seen in Figure 73. One set of poles and one set of backing bars are shown. The poles are actuated from a central transmission in the center of the crack sensor body. The pole actuator transmission has 30 points connected to 30 poles to drive radially outward to the pipe wall. The remaining poles are connected to driven poles. A shunt mechanism is driven from each end by each of the six magnetic sections for a total of 12 motors. Both the pole-expanding motors and the shunt motors are controlled from two motor controllers on each end of the sensing section. Additionally, power control, communications, and EMAT synchronization are controlled from each end of the sensing section. All control boards are mounted on two connector boards on each end of the sensing section. Motors, sensors, and other peripherals are mounted on the connector boards, simplifying assembly, testing, and debugging.

[0160]

[0244] A steering module attached to each end of the crack sensor contains support wheels that support the sensor's weight during testing. This support method further reduces the traction forces on the crack sensor to levels comparable to those of conventional axial MFL systems currently towed by Explorer. All new components were individually pressure tested to 5.2 MPa (750 psi) to ensure operation during field testing.

[0161]

[0245] Overall, the new crack detection section consists of the following components:

[0246] Six collapsible magnetic pole sections that contact the pipe wall, each with up to 10 poles.

[0162]

[0247] Each magnet pole is spiraled to achieve complete coverage of the pipe circumference.

[0248] Hall sensors are placed between the poles to measure the magnetic flux leakage.

[0163]

[0249] Two EMAT transmitters and four EMAT receivers are positioned at the pole ends.

[0250] The magnetic section is supported within the pipe with foldable rollers at each end.

[0251] A customized steering module properly positions the crack sensor and rotates it through the pipe.

[0164]

[0252] These crack sensor analysis tools are functions and methods used to organize data for viewing and ultimately sizing identified anomalies within the data. Data is collected and organized separately until it can be viewed side-by-side in vision software (commercially available under the name DataTel). There are four main types of data collected by the robot during a crack sensor scan. First, the navigational robot configuration is recorded when the robot is within the pipeline. From this data, an analyst can determine the robot's position and potentially other indicia of defects, such as markings on the inside of the pipe. Second, the robot collects MDS (Mechanical Damage Sensor) data using three cameras and a laser ring on the rear section of the robot. This process is described in the previous section. Third, the crack sensor collects TMFL data on 24 individual sensor elements arrayed around the pipe wall. This data is stored directly on the sensor elements and downloaded at the end of the inspection. Fourth, EMAT data is collected and stored in four receivers arrayed around the pipe wall.

[0165]

[0253] Robot Configuration: As currently designed, the entire configuration of the robot, gathered from angle and position sensors throughout the robot, is recorded during run time. After run time, the robot's position can be reconstructed, along with battery level, power status, communication strength, and more. This is done using a parser that extracts and plots various variables from the robot log file. The log file also contains odometer information for the robot, tracking its position within the pipe. This information is used to define the scan, which breaks down the raw data into segments for processing. Defining the scan includes a temporal and spatial synchronization step that aligns and maps all data to specific locations within the pipe. For the robot configuration data, once the scan is defined, parameters are set up in the vision software to access specific locations within the log file for automated viewing of the video and robot position. While sizing is not explicitly performed using the robot configuration, some markings on the interior walls can be seen, including circumferential welds, debris, discoloration, manufacturer's marks, large bends, and even large corrosion patches. These inputs are used to validate other data from the MDS, EMAT, and TMFL sensors.

[0166]

[0254] Transverse flux leakage: TMFL data handling is integrated into the vision software during the assembly process. Data handling of TMFL data is performed by Axial MFL Technology. The Hall sensor data is collected and stored in the same way, and the same scripts are used to spatially sample these data, so the resulting data files for input into DataTel are the same. DataTel was slightly modified to differentiate between TMFL and axial MFL data using the configuration robot at start-up.

[0167]

[0255] There are three main differences between the response of the TMFL data and the axial MFL data:

[0256] (1) TMFL data is sampled using only the radial component of the magnetic flux leakage pattern. This means that the signal behavior is more sensitive to sensors that are lifted away from the pipe wall than conventional sensors. The signal pattern is comparable to the axial case.

[0257] (2) There are four sensor elements within each slope, staggered to ensure complete coverage. This causes a slight overlap on the sensors, which must be taken into account during pre-processing.

[0258] (3) The sensor elements are offset from each other along the pipe axis, meaning that they measure different areas of the pipe at different scan positions, which requires the analyst to vary the readings relative to each other when spatially registering the data.

[0168]

[0259] FIG. 74 shows a schematic of the crack sensor and MDS handling.

[0260] The major obstacles encountered when using TMFL are the calibration of the sensor and the development of sizing algorithms that can determine the depth of the crack once it is detected.

[0169]

[0261] Electromagnetic ultrasonic transducer (EMAT):

[0262] The crack sensor collects EMAT data from multiple receivers around the pipe wall in response to pulses generated by multiple pulsers. This data is stored directly as samples in the EMAT receivers. Each pulse generates one sample in each receiver. A sample of the experimental unit used for testing is shown in Figure 75. This illustration shows a cross section of the pipe with pulsers (transmitters shown in pink) and receivers shown in gold. There are two receivers between any pair of pulsers. The arrows along the pipe wall indicate the direction of the generated shear waves. Typical waves picked up by the receivers are shown in Figures 76 and 77. In the ultrasonic testing industry, this is known as an amplitude modulation scan, or A-scan.

[0170]

[0263] Direct Pulse - This is the very first wave the receiver can detect and has the highest amplitude. It has the shortest path between the transmitter and receiver. This pulse can be attenuated by the presence of features such as variations in wall thickness, seam welds, and / or defects.

[0171]

[0264] Feature Reflections - Wave reflections from features are read by the sensor later than the direct pulse because they have to travel a longer distance. They can appear any time after the direct pulse and are usually smaller in amplitude.

[0172]

[0265] First travel - These are equivalent to a direct pulse after it has traveled a full circle around the pipe. They appear as pairs because the transmitter emits pulses in both directions. One pulse travels a shorter distance because the transmitter and receiver are not in the same location.

[0173]

[0266] If a sensor is moved through the pipe and sampled at discrete points, the signals can be superimposed next to each other. Distance is plotted on the x-axis and time is plotted on the y-axis. The amplitude is plotted on the z-axis or via the color of the contour plot. A sample of this plot is shown in Figure 78. The direct pulse has the largest value and is shown as a coincident line at the bottom of the plot. This line is straight because the distance between the pulser and receiver is fixed by the test equipment. The adjacent line that can be seen is the seam weld reflection. A double peak of back and forth can then be seen in the signal.

[0174]

[0267] A real-time data plot for the EMAT-equipped Explorer has been implemented to allow the operator to assess the signal quality during the test.

[0175]

[0268] In the present embodiment of the invention described herein, the ability exists to process data from all EMAT channels on a sensor to perform spatial sampling of the channel magnitudes and analyze the channel magnitudes.

[0176]

[0269] Pipeline Cleaning:

[0270] Many different technologies and techniques are used to prepare pipelines for evaluation with in-line inspection tools. Applying these technologies involves planning and executing cleanings, often multiple times, to ensure the pipeline walls are free of buildup and debris. A clean pipe wall is important for in-line inspection because measuring metal loss typically means that positioning sensors are located near or directly inside the pipe wall. Furthermore, cleaning the pipe typically means savings for the pipeline operator in terms of operational costs associated with equipment reliability and product throughput efficiency. When pipelines cannot be pigged by conventional means, specialized robots are used to navigate the pipeline. While there are many different methods for moving through the pipe, sensing technologies are required to optimize sensitivity and access the pipe wall. An evaluation of methods for combining these known technologies to clean pipelines that cannot be pigged was conducted by InvoDane Engineering (IE).

[0177]

[0271] To understand the approach for applying cleaning techniques to non-piggable pipelines, the following approach is taken: (a) evaluate the current cleaning methods used prior to in-line inspection; (b) evaluate the current capabilities for navigating non-piggable pipelines using Explorer; (c) develop general cleaning requirements; and (d) evaluate the configuration of non-piggable cleaning concepts.

[0178]

[0272] Pipeline Cleaning Background:

[0273] Pipeline cleaning can be categorized into three basic functional steps (see Figure 79). First, debris or buildup is removed from the pipe walls. This can be done by a variety of means, such as scrapers, brushes, and / or plows, and may be assisted by other means, such as pressure jets or chemicals. The particles / debris from the pipe walls are then transported through the pipeline. Finally, the particles / debris are removed from the pipeline environment via pig traps, treatment equipment, or in some cases, suction pumps.

[0179]

[0274] Non-piggable cleaning:

[0275] From the generalized requirements and available cleaning technologies, it is possible to evaluate the range of technologies available for pipeline cleaning and to determine which technologies are suitable for non-piggable cleaning. Explorer's technology can be used as the basis for a platform to be developed for pipeline cleaning in lines where cleaning is not possible.

[0180]

[0276] Generally, any method involving the use of a liquid-phase product is not considered, since adding liquid into the pipeline would require a follow-up "cleaning" to ensure the liquid is removed. Magnetic debris that would be picked up by the sensing section of the inspection tool (the MFL sensor) and could cause problems can be removed with another set of magnets, if necessary. This allows brushes and scrapers, as available technology, to be used on a robotic platform for pipeline cleaning.

[0181]

[0277] The configurations used in non-piggable cleaning are applicable to both flowing and non-flowing pipeline sections. The range of applicability of each configuration is determined through testing and by the parameters of the individual pipeline.

[0182]

[0278] By utilizing the constraints listed above, the current Explorer technology will be used in part as the technology to be built to achieve non-piggable cleaning, thus maintaining radio-controlled and self-powered operation.

[0183]

[0279] Non-piggable cleaning using flow: In this configuration, a cleaning module (for removing debris from the wall) is placed between the two drive modules (see Figure 80). The cleaning module is responsible for removing debris from the pipe wall. Different cleaning sections are employed for different debris scenarios. A camera is installed to monitor the cleaning progress and to give the operator a degree of control over the cleaning process. A foldable throttle mechanism may be located on the tool, which will create a pressure differential across the tool. The primary purpose of this throttle mechanism is to create a jet of water to suspend the debris at the front part of the tool, not towards the pipe wall to detach it. Care must be taken in developing this device, as a small pressure drop will create a large force on the tool. This pressure differential will be used to "energize" the flow and propel the debris towards the front part of the tool.

[0184]

[0280] Cleaning is performed by the bristles and scrapers as the tool moves with the flow. The force created by the pressure differential used to create the flow jet can also provide momentum for the tool, thereby assisting the energy required to pull the cleaning module through the pipe.

[0185]

[0281] The technology to be used will be evaluated in the context of debris accumulation and its operational impact. Visibility will also be a consideration. Cleaning tools could use a launch configuration similar to the current Explorer. Other ancillary functionality, such as in-line charging, and salvage tools could also be applied to this system.

[0186]

[0282] The cleaning module is configured to pass through plug valve geometries for pipe sizes from 20 inches to 36 inches. This allows cleaning through elbows and tees. Miter bends are cleaned along the tool path, resulting in the tool contacting the majority of the bend. In the case of a 90-degree miter, a portion of the outside corner may remain untouched, as would be the case with an inspection robot.

[0187]

[0283] As debris dislodges from the pipe wall and becomes suspended in the gas flow, a debris cloud forms. The debris is generated and moves continuously along the pipe. How it is handled is determined by the pipeline configuration. Options include: (a) moving continuously along the pipeline until it stops outside the inspection area or where it can be swept away using a conventional cleaning pig; (b) moving continuously along the pipeline until it reaches a standard receiving chamber or separator. This is the case when the tool uses a conventional pigging installation complete with a gas-solids separator to clean the branch of a tee where it enters the main line; (c) a portable gas-solids separator unit is mounted on the pipeline at the downstream hot tap. The flow is diverted into the tap, passed through a separator (see Figure 81), and returned to the pipeline at a second hot tap located downstream or specially diverted within the same hot tap. For larger pipes, it may be necessary to mount multiple separator units. Figure 82 shows a portable separator for discharge at a wellhead.

[0188]

[0284] Pig cleaning with normal flow is not possible:

[0285] To create a suitable operating case for the tool configuration, it is necessary to minimize the number of hot taps. This is because non-piggable pipes limit the options available for hot tap location. The distance between hot taps is determined by the tool range, as in the inspection case. An example non-piggable line is shown in Figure 83. It demonstrates the following cases: (a) a flowing pipeline with non-piggable features (blue), and (b) a line with no flow with non-piggable features (red). All lines are pressurized to pipeline pressure.

[0189]

[0286] For an example non-piggable line, consider two mission profiles (operating conditions). For the non-piggable cleaning case with normal flow, the tool path is shown by the orange arrow and begins at the upstream hot tap (location 2). A gas-solids separator is installed on the right side of the diagram at location 1. Flow through the section to be cleaned flows from left to right, passing non-piggable features such as plug valves and mitered bends. Charging points for the tool are present at the upstream hot tap and possibly at intermediate points throughout the section to be cleaned (5b). The steps for cleaning a pipe section are described below (see the numbered locations in Figure 84 for each step). a. A gas-solid separator is mounted on the hot tap downstream of the section to be cleaned. b. The tool is launched through an upstream hot tap. Note that if the tool is launched from location (1), only one hot tap may be required for inspection, provided that cleaning is performed upstream of the gas-solid separator. c. (Optional) The tool is driven upstream to clean and return to the original hot tap. d. The tool recharges. e. Cleaning step: (a) The tool moves to clean downstream through features that cannot be pigged; (b) In-line charging specifications may require a charging location between the upstream and downstream hot taps through a two-in-one hot tap. The tool will move until it reaches the end hot tap or charging location. The tool will recharge if necessary. f. Washing steps are repeated as needed (5a-5c). g. The tool moves and cleans downstream, eventually reaching the outlet hot tap, at which point the gas-solids separator disconnects from the pipeline and the debris is removed and discarded. h. The launcher is attached and the tool is unlaunched.

[0190]

[0287] During a cleaning run, the tool can be inverted and returned to any location requiring additional cleaning. If the buildup is particularly thick, the cleaning tool can make multiple passes over the entire section to be cleaned. With such continuous operation, debris can be removed from the separator during or after operation.

[0191]

[0288] Claim examples:

[0289] An autonomous robotic non-piggable pipeline testing system comprising one or more of the following in combination:

[0290] 1. A method for reducing the operational complexity of conventional in-line pipeline testing and for providing a unique and novel method for pipeline testing, the method comprising:

[0291] Novel computerized autonomous robotic systems;

[0292] energy utilization means for utilizing the flow of gas in the pipeline to operate the turbine means, to function the robotic traction capability, and to operate the charging of the battery;

[0293] Novel drive means;

[0294] novel barrier measures;

[0295] Automation computer means;

[0296] Novel feature recognition measures;

[0297] Novel obstacle detection means;

[0298] Novel curvature detection means;

[0299] Novel T-pipe detection method;

[0300] Pipeline mapping measures;

[0301] Novel plug valve navigation and functionality means;

[0302] Novel robot battery power distribution;

[0303] Novel hardness testing methods;

[0304] Novel transverse magnetic flux leakage sensing means;

[0305] Novel electromagnetic ultrasonic transducer means;

[0306] A novel crack sensor analysis tool; and

[0307] A new pipeline cleaning method

Claims

1. a remote-controlled robotic assembly movable within a stream of gas flowing in a pipeline, the gas flow exhibiting kinetic flow energy, the robotic assembly having a rotary turbine responsive to the gas flow; a generator responsive to the turbine; a battery responsive to the generator; drive traction means responsive to said generator for moving said assembly; Equipped with the system is capable of extracting the kinetic flow energy for one or both of operating the drive traction means and charging the battery; Autonomous robotic active gas transmission pipeline testing system.

2. The robotic system of claim 1 , comprising a plurality of modules, each module capable of performing at least one function to facilitate testing or observation of the system.

3. 1. A means for reducing the operational complexity of conventional in-line pipeline testing and for providing a unique and novel means for pipeline testing, comprising: computerized autonomous robotic systems, energy utilization means for utilizing the flow of gas in the pipeline to operate the turbine means, to function the robotic traction capabilities, and to activate the charging of the battery; drive means, Barrier means, Automation computer means, Feature recognition means, Obstacle detection means; Curvature detection means; Tee pipe detection means; Pipeline mapping means; Plug valve navigation and functionality means, Robot battery power distribution, hardness testing means, Transverse magnetic flux leakage sensing means; an electromagnetic ultrasonic transducer means; crack sensor analysis means, and Pipeline cleaning means 1. An autonomous robotic non-piggable pipeline testing system comprising one or more of the following in combination:

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