Patent ID: 12252198

DETAILED DESCRIPTION

Embodiments of the present disclosure are directed to a robotic apparatus for traversing the exterior of piping systems, such as ones commonly found in chemical plants, power plants, manufacturing plants, and infrastructure. Piping systems can be complex and present various obstacles that can make it difficult to traverse individual pipes in an efficient and effective manner. For example, as shown inFIG.4A,FIG.4B,FIG.4C,FIG.4D, andFIG.4E, representative obstacles may include supports11(FIG.4A), junctions12(FIG.4BandFIG.4C), flanges13(FIG.4C), valves14(FIG.4C), vents or bleeders (similar to smaller valves), changes in diameter15(FIG.4D), and bends16(FIG.4E), amongst others such as nearby pipes and other nearby structures (later shown inFIG.21andFIG.22A,FIG.22B,FIG.22C,FIG.22D, andFIG.22E). Various embodiments of the robotic apparatus may be configured to traverse pipes10and navigate such obstacles as encountered through a unique architecture and approach, as later described in more detail. The robotic apparatus may also be adapted to traverse the exterior of other structures that are similarly shaped, such as structural cables (e.g. on suspension bridges), structural beams, powerlines, underwater cables and underwater piping systems.

Embodiments of the present disclosure may be useful in many applications including, without limitation:Pipeline inspection using cameras, non-destructive testing (NDT or NDI), or other sensors;Inspecting equipment in the vicinity of the piping systemPerforming maintenance on the piping system (e.g., cleaning the external surface, removing insulation, applying a patch/clamp to stop a leak)Transporting tools or equipment along the piping system (e.g., facilitating installation of sensors on the pipe).

Various embodiments of the robotic apparatus may be capable of traversing pipes arranged in any orientation (including horizontal and vertical), and pipes made of any material (e.g., steel, aluminum), even those with insulation about the exterior of the pipe. Insulation is typically a semi-rigid material, such as a mineral wool or calcium silicate, protected by a thin metal jacket, such as aluminum or stainless steel. For clarity, the outer surface of any insulation on the exterior of a pipe may, for simplicity, be referred to as the outer surface of the pipe. As such, references herein to the robotic apparatus being positioned on, secured to, contacting, or otherwise interfacing with the outer surface of a pipe should not be strictly construed as referring only to interfacing with the metal exterior of the pipe under such insulation, but rather may additionally or alternatively encompass the robotic apparatus being positioned on, secured to, contacting, or otherwise interfacing with the outer surface of the insulation on the exterior of the pipe. Simply stated, references to the outer surface of the pipe should be construed as the outer surface of insulation on the pipe when discussing the robotic apparatus in the context of traversing insulated pipes.

Generally speaking, embodiments of the robotic apparatus of the present disclosure may attach to a pipe by applying a clamping force on opposing sides of the pipe. Various embodiments may be capable of holding a static position on the pipe and may support its own weight on a range of pipe sizes in any orientation (e.g., horizontal or vertical). The robotic apparatus, in various embodiments, may be configured to drive along paths in the longitudinal direction of the pipe (sometimes referred to herein as axial translation), in a circumferential direction on the pipe (sometimes referred to herein as circumferential translation), along a helical path (i.e., a combination of circumferential and longitudinal vectors), and various combinations thereof, on pipes of varying sizes and orientation. Such maneuvering, in combination with the ability to expand or contract the clamping arm around the pipe, and the robots low-profile and open-sided architecture, may allow the robotic apparatus to navigate a variety of bends and obstacles encountered along the length of the pipe. A low profile of the robotic apparatus may enable it to drive along pipes in close proximity to other pipes or obstacles situated close by. The robotic apparatus may additionally be capable of actively controlling the amount of clamping force it exerts on the pipe, thereby allowing the robot to selectively apply more clamping force in situations where additional traction is desired (e.g., while climbing or remaining stationary a vertical pipe) and selectively apply less clamping force in situations where less traction is desired (e.g., while traversing a horizontal pipe), which can help reduce power consumption and thus battery size, motor size, and associated weight. Active control of clamping force can also help ensure that the robotic apparatus does not damage the pipe or insulation. Further, the robotic apparatus may be capable of actively sensing whether the wheels slip on the pipe surface and actively control individual wheels to steer the robotic apparatus back to the centerline of the pipe.

The robot, in various embodiments, may have a modular architecture in which various components can be added, removed, or replaced with similar components having different properties. Such modularity can allow the robotic apparatus to be reconfigured in the field as needed to adapt to different operating conditions, such as for operation on pipes of varying sizes (diameter) and orientations (e.g., horizontal, vertical), and to carry different payloads (e.g., inspection sensors, batteries).

In various embodiments, the robotic apparatus may be configured to carry and deploy a payload along the pipe, such as cameras (e.g. visual spectrum and IR cameras), various sensors like NDT sensors (e.g., ultrasonic testing probes, pulsed eddy current probes, digital radiography equipment, acoustic sensors) and gas monitors for the purpose of inspecting the piping system or equipment in its vicinity, and/or other payloads like tools and equipment. The robotic apparatus, in various embodiments, may include an onboard power supply (e.g., batteries) and operate via wireless communication with an operator, thereby obviating the need for a power cord or tether. Of course, in various embodiments, the robotic apparatus may utilize a power cord (or other suitable power source) and/or wired communication (or other suitable communications means). Such a configuration may be advantageous in certain cases, such as if one or more components of a particular payload (e.g., an NDT instrument) is too large to be carried onboard while maintaining the robot's low profile as described herein. In such an example, the NDT probe could be located onboard the robotic apparatus and connected to the NDT instrument on the ground with the operator via a power cord and/or tether.

Robotic Apparatus100

High-Level Architecture

FIG.5Ais a perspective view of a representative embodiment of robotic apparatus100. Robotic apparatus100, in various embodiments, may generally include four or more wheels111having a plurality of rollers112disposed about a circumference thereof. Wheels111can rotate (freely or under power) much like a traditional wheel, and the rollers112on each wheel111may freely rotate about their respective rotation axes on the main wheel portion itself. Generally speaking, rollers112allow a respective wheel111to slide laterally or with a lateral vector component (depending on an orientation of the rollers112about the circumference of wheel111) on the surface of pipe10with minimal friction when the robotic apparatus100is moving in a direction not fully aligned with the direction of rotation of the respective wheel111. In some embodiments, rollers112have rotation axes perpendicular to the main axis of rotation of the main wheel portion (not shown), while in other embodiments, rollers112may have rotation axes that are angled relative to the main axis of rotation of the main wheel portion (e.g., at 45 degrees as shown). Sometimes referred to as poly wheels, omni wheels, or mecanum wheels, such wheels111having rollers112are generally known in the art and the present disclosure should not be limited to any particular embodiment thereof unless specified exclusively. Even when a particular embodiment is specified (e.g., wheels with mirrored 45 degree angle rollers), one of ordinary skill in the art will recognize alternative configurations suitable for producing the same motion on pipe10.

In various embodiments, the diameter of wheels111may be chosen based on the size of certain obstacles encountered on the surface of the pipe. Generally speaking, it may be preferable to use a large enough wheel111to drive over such obstacles, but no larger, so as to minimize the amount of clearance needed around pipe10in order for robotic apparatus100to travel. The diameter necessary to drive over such obstacles can vary based on many factors (e.g., traction, torque, speed), but testing has shown that diameters twice the height of such obstacles are sufficient. One having ordinary skill in the art will be able to select an appropriate wheel diameter based on the teachings of the present disclosure without undue experimentation.

Robotic apparatus100, in various embodiments, may generally include four wheels111, with half of the wheels111(e.g., first and second wheels111a,111bin the four-wheeled embodiment shown) configured to be positioned on a first side of pipe10and half of the wheels111(e.g., third and fourth wheels111c,111din the four-wheeled embodiment shown) configured for positioning on a second, opposing side of pipe10. For clarity, unless otherwise specified herein, the terms “first side” and “second, opposing side” of a pipe both refer to the exterior surface of the pipe (or insulation thereon, if the pipe is insulated) and, more specifically, to circumferentially-opposing halves thereof.

Wheels111a,111band wheels111c,111d, in various embodiments, may be grouped onto separate drive platforms110a,110b(shown, but not labeled), especially in modular embodiments of robotic apparatus100, as later described in more detail. One or more clamping members130(two shown here) may couple the first and second wheels111a,111bwith the third and fourth wheels111c,111dand be configured to apply a force for urging the first, second, third, and fourth wheels111towards an outer surface of the pipe10for securing the robotic apparatus100to the pipe10.FIG.5Billustrates the robotic apparatus100ofFIG.5Asecured to pipe10.

FIG.6Ais a perspective view of another representative embodiment of robotic apparatus100. In this representative embodiment, robotic apparatus100includes eight wheels111, with (i) first and second wheels111a,111band fifth and sixth wheels111e,111fconfigured to be positioned on a first side of pipe10and (ii) second and third wheels111c,111dand seventh and eighth wheels111g,111hconfigured to be positioned on a second, opposing side of pipe10. Wheels111a,111b,111e,111fand wheels111c,111d,111g,111h, in various embodiments, may be grouped onto separate drive platforms110a,110b(shown, but not labeled), especially in modular embodiments of robotic apparatus100, as later described in more detail. One or more clamping members130(two shown here) may couple the first, second, fifth, and sixth wheels111a,111b,111e,111fwith the third, fourth, seventh, and eighth wheels111c,111d,111g,111hand be configured to apply a force for urging the wheels111towards the outer surface of the pipe10for securing the robotic apparatus100to the pipe10.FIG.6Billustrates the robotic apparatus100ofFIG.6Asecured to pipe10.

Embodiments of the present disclosure may, of course, comprise any number of wheels111and clamping members130suitable for securing robotic apparatus100to pipe10and enabling the motions later described herein. For ease of explanation only, embodiments of the present disclosure will primarily be described in the context of an eight-wheeled robot; however, one of ordinary skill in the art will recognize, based on the teaching of the present disclosure, how to adapt the concepts described herein to embodiments of robotic apparatuses100having a different number of wheels111.

Various wheels111may be powered such that robotic apparatus100may travel along pipe10in axial and circumferential directions and in various combinations thereof (e.g., along helical paths of varying pitch), and thereby position robotic apparatus100to pass over a particular portion(s) of pipe10and/or avoid an obstacle(s) extending from a surface of pipe10, as later described in more detail.

Drive Platform110

FIG.7is a perspective view of a representative drive platform110of robotic apparatus100. In an eight-wheeled embodiment such as that shown inFIG.6A, wheels111a,111b,111e,111fmay be grouped onto a first drive platform110aand wheels111c,111d,111g,111hmay be grouped onto a second drive platform110b. Various embodiments of drive platform110may generally include a frame113onto which wheels111and motors125are mounted.

With continued reference toFIG.7, wheels111may be oriented such that the axis of rotation of each wheel111is parallel with a longitudinal axis of pipe10when robotic apparatus100is secured to pipe10. Such orientation, in combination with the orientations of rollers112of each respective wheel111, allows robotic apparatus100to move in all directions along pipe10as well as maintain substantially uniform contact with the outer surface of pipe10across an entire width of each wheel111. For example,FIG.8A,FIG.8B,FIG.8C, andFIG.8Dillustrate a difference in surface contact between a wheel111oriented as described herein and that of a wheel oriented similar to those shown inFIG.3(prior art), when placed on pipes10of varying diameter. By virtue of orienting wheels111such that their axes of rotation are parallel to the longitudinal axis of the pipe, wheels111of the present disclosure maintain substantially uniform contact with pipe10across the entire width of each wheel, as shown in each ofFIGS.8A-8D. Conversely, a robot with wheels oriented similar to those ofFIG.3only has substantially uniform contact on one particular diameter of pipe (FIG.8B) and the robot starts to ride on its wheel edges on smaller or larger pipes.

Wheels111, in various embodiments, may be grouped into pairs in which the rollers112of one wheel111have an orientation mirroring that of the rollers112on the other wheel111. For example, in the four-wheeled embodiment of robotic apparatus100shown inFIG.5A, the orientation of rollers112of wheel111amirrors that of the rollers112of wheel111b, and the orientation of rollers112of wheel111cmirrors that of the rollers112of wheel111d. Likewise, in in the eight-wheeled embodiment of robotic apparatus100shown inFIG.6A, the orientation of rollers112of wheel111amirrors that of the rollers112of wheel111b, the orientation of rollers112of wheel111cmirrors that of the rollers112of wheel111d, the orientation of rollers112of wheel111emirrors that of the rollers112of wheel111f, the orientation of rollers112of wheel111gmirrors that of the rollers112of wheel111h. In the embodiments shown, such pairings are made between wheels111that are circumferentially offset from one another at the same axial location on a given side of pipe10; however, it should be recognized that such pairings may be made between wheels111that are axially offset from one another at the same circumferential location on a given side of pipe10—especially in embodiments where all wheels111on a given side of pipe10are at the same circumferential position (not shown). One of ordinary skill in the art will recognize, based on the teachings of the present disclosure, roller orientation configurations suitable for enabling robotic apparatus100to move in all directions along pipe10as later described herein.

Wheels111may be mounted to a frame113of drive platform110. Frame113, in various embodiments, may be configured to position wheels111in the various configurations described herein. Frame113, in various embodiments, may include one or more lateral frame members114configured to position, for example, wheels111a,111bat circumferentially offset locations from one another on pipe10and wheels111e,111fat circumferentially offset locations from one another on pipe10, as shown inFIG.7. Lateral frame member(s)114, in various embodiments, may have a curvature designed to match that of the outer surface of a representative pipe10to which robotic apparatus100will be secured. Additionally or alternatively, frame113, in various embodiments, may include one or more longitudinal frame members115configured to position wheels111a,111bat axially offset locations from wheels111e,111fon pipe10. Frame113, in various embodiments, may further support one or more motors125for powering one or more of wheels111. In the embodiment shown, each wheel111is separately powered by a corresponding motor125; however, one of ordinary skill in the art will recognize that, in various embodiments, fewer than all of the wheels111may be powered and/or that multiple wheels111may be powered by one motor125. In such cases as the latter, it should be further recognized that robotic apparatus100may further include a transmission (not shown) that permits the multiple wheels powered by one motor125to be selectively engaged/disengaged from powered rotation, rotated at different speeds from one another, and/or rotated in different directions from one another. Accordingly, one having ordinary skill in the art will recognize various numbers and combinations of motors125(and, if applicable, corresponding transmission configurations) suitable for use with various numbers and configurations of wheels111without undue experimentation.

FIG.9andFIG.10schematically depict an embodiment of drive platform110configured to allow the longitudinal and lateral positions of wheels111to be adjusted thereon. Referring first toFIG.9, in some embodiments, a longitudinal offset between wheels111may be adjusted by repositioning lateral frame members114on longitudinal frame member115. For a smaller offset, lateral frame members114may be moved closer together on longitudinal frame members115and, for a larger offset, lateral frame members114may be moved further away from one another on longitudinal frame members115. In the embodiment shown, frame113may comprise adjustable mounting hardware (such end cap117, clamp119, and adjustable length spacers118therebetween) to secure lateral frame members114in the desired longitudinal locations during the adjustment. Referring now toFIG.10, additionally or alternatively, in some embodiments, a lateral offset between wheels111may be adjusted by repositioning wheels on lateral frame members114. In various embodiments, lateral frame members114may comprise a slot or other mounting features (not shown) that allow for wheels114(and corresponding motors125) to be repositioned along the length of lateral frame member114.

The ability to adjust the relative positioning of wheels111on some embodiments of drive platform110may allow robotic apparatus100to be adapted to various operating environments without having to swap out one set of drive platforms110with one particular wheel configuration well suited for one operating environment for another set of drive platforms110with a different wheel configuration better suited for a different operating environment. For example, increasing the lateral offset between wheels111on drive platform113(and thus the circumferential positioning of wheels111on pipe10) can provide additional stability to the robotic apparatus100on pipe10and, conversely, decreasing the circumferential offset can increase the size of open side139of robotic apparatus opposite clamping member130as shown inFIG.10and thereby allow robotic apparatus to navigate larger obstacles on or near pipe10. In many cases, it may be preferable to provide as much lateral offset as possible (for increased stability) while still maintaining a large enough open side139for anticipated obstacles to pass through. As another example, increasing the longitudinal offset between wheels111on drive platform113(and thus the axial positioning of wheels111on pipe10) can allow for more or larger electronics and batteries to be positioned between the longitudinally offset wheels111(later shown inFIG.11), whereas decreasing the longitudinal offset can improve the ability of robotic apparatus100to traverse pipe10having a combination of obstacles that are in different orientations and close together. Stated otherwise, if pipe10has two obstacles that are 180 degrees apart (circumferentially) and two feet apart (axially), a robotic apparatus100with a longitudinal offset of less than two feet could traverse these obstacles, but one having a greater longitudinal offset may not. The shorter robotic apparatus100could, for example, (i) traverse the first obstacle by aligning open side139with the first obstacle and advancing axially past the first obstacle until robotic apparatus100is positioned between the two obstacles, and (ii) traverse the second obstacle by maneuvering circumferentially to align open side139with the second obstacle and then advancing axially to clear the second obstacle. A robotic apparatus100with a larger longitudinal offset may not be capable of fitting axially between the obstacles and thus could not execute such maneuvers to traverse the two obstacles. One having ordinary skill in the art will recognize, based on the present disclosure, a longitudinal offset suitable for balancing the need to accommodate certain sized payloads with the need for having sufficient axial clearance to navigate obstacles positioned axially close together. Of course, as later described in more detail, the modularity afforded by the ability to swap out drive platforms110and clamping members130is in and of itself highly beneficial and not to be discounted. In some embodiments, wheel position is adjustable on modular drive platforms110as well.

FIG.11shows the drive platform110ofFIG.7outfitted with various payloads, such as battery126and electronics circuit board127. Battery126may power motors125, electronics hardware127, sensor payloads140(later shown inFIG.16), and other onboard electronics. Electronics hardware127may contain components for operating robotic apparatus100, such as a circuit board with a controller configured to actuate motors125in accordance with executable instructions stored on a memory component. In some embodiments, payload(s) may be carried on one or more drive platforms110, on frame113, or on any other suitable location on robotic apparatus100. Of course, robotic apparatus100could additionally or alternatively be powered via a power cord or other suitable power source in various embodiments.

As later shown inFIGS.21A and21D, a detachable umbilical cord may be used to connect various payloads (for power and/or electronic communications), which may be particularly convenient in modular embodiments where drive platforms110may be swapped out for use in various operating environments. In some embodiments, the detachable umbilical cord is external to robotic apparatus100and secured so as not to flop around, while in other embodiments, body portion131of clamping member130may be equipped with internal electronic conduits (e.g., wires) connecting electronic contacts on ends132. In the latter example, drive platforms110(or frame113or other suitable structure associated with opposing sets of wheels) may also include electronic contacts positioned such that the electronic contacts on clamping member130are in electrical communication with the electronic contacts on drive platforms110when clamping member130is installed. As configured, simply installing clamping member130may place drive platforms110into electronic communication with one another, thereby allowing for power and electronic communications to be routed therebetween.

While much of the present disclosure discusses wheels111and motors125in the context of being mounted on modular drive platforms110, it should be recognized that (i) wheels111may be mounted on any structure suitable for positioning and orienting wheels111in at least one of the configurations described herein; (ii) motor(s)125may be mounted in any suitable location on any structure suitable for allowing motor(s)125to drive wheels111, whether directly or through a transmission; and (iii) drive platforms110need not be modular (i.e., selectably attached/detached from clamping member130) but rather can be permanently affixed to clamping member130.

Clamping Member130

FIG.12Ais a perspective view of a representative clamping member130of robotic apparatus100. Generally speaking, clamping member130, in various embodiments, may couple the wheels111positioned on a first side of pipe10with the wheels111positioned on a second, opposing side of pipe10, and may be configured to apply a force for urging the wheels111towards an outer surface of the pipe10for securing the robotic apparatus100to the pipe10. For ease of description, this force may also be referred to herein as the “clamping force.”

The amount of clamping force needed is primarily governed by the weight of robotic apparatus100and the friction of wheels111on the surface of pipe10. Generally speaking the clamping force should be enough for wheels111to have sufficient normal force to generate friction sufficient to propel the weight of robotic apparatus100. For example, if robotic apparatus100weighs 20 pounds and is traversing a vertical pipe10with a coefficient of friction between wheels111and pipe10equal to 0.5, then the total clamping force needed may be at least 40 pounds-force. That said, if the clamping force is too large, wheels111may deform some pipes with softer insulations and robotic apparatus100would need to increase the driving force needed to drive over obstacles on the surface of the pipe10. Larger clamping forces also require the use of stronger components, which can increase the weight of robotic apparatus100.

As shown throughout the FIGURES, in some embodiments, robotic apparatus100may include two or more clamping members affixed at any given time. In still further embodiments, robotic apparatus100may be provided as a kit with multiple clamping members of different properties, and each may be interchanged to tailor the robotic apparatus for use under corresponding operating conditions.

Clamping member130, in various embodiments, may include a body portion131connecting first and second ends132. Body portion131, in various embodiments, may have a curvature and size designed to substantially complement that of the curvature and diameter of a representative pipe10to which robotic apparatus100will be secured. More specifically, in various embodiments, the curvature of body portion131may be semi-circular and sized such that ends132are positioned over opposing sides of pipe10and, most preferably, at directly opposing circumferential positions about pipe10as shown inFIG.12B. Such positioning allows for clamping member130to apply the clamping force through ends132at directly opposing vectors through the centerline of the pipe10, which may better secure robotic apparatus100to pipe10than configurations in which the clamping force vectors at ends132are not directly opposing and possibly do not pass through the centerline of pipe10. Of course, such a configuration is not necessary to securely couple robotic apparatus100to pipe10and, in many cases, the same clamping member130may be used on pipes10of fairly similar diameters and still adequately secure robotic apparatus to such pipes10. Likewise, clamping member130need not necessarily have a curvature directly complementing that of the outer surface of pipe10so long as the shape of clamping member130is capable of applying a clamping force suitable for securing the robotic apparatus100to the pipe10. Notwithstanding the foregoing, in various embodiments it may be advantageous for clamping member130to have a size and curvature that highly complements that of the pipe10on which it will travel such that clamping member130can be positioned very close to the outer surface of pipe10without causing interference. As configured, clamping mechanism may be provided with a very low profile that allows it maximum clearance to navigate operating environments in which obstacles (e.g., other pipes) are positioned very close to pipe10.

Clamping member130, in various embodiments, may comprise any material(s) and construction suitable for applying the clamping force when robotic apparatus is installed on pipe10. In some embodiments, clamping member130may be substantially rigid, while in other embodiments, clamping member130may have a high stiffness but still be flexible enough for body portion131to bend when ends132are pulled apart. In rigid embodiments, clamping member130may serve as a backstop for a biasing mechanism (e.g. spring or adjustment screw) to push the drive platforms110inwards towards pipe10and thereby provide the clamping force, as later described in more detail. A stiff-but-flexible construction may allow clamping member130to be pried open to an expanded state during installation of robotic apparatus100on pipe10and then released once drive platforms110are properly positioned on pipe10, allowing clamping member130to contract back to its neutral state and thereby apply the clamping force. One having ordinary skill in the art will recognize, based on the present disclosure, various sizes, curvatures, material(s), and constructions suitable for providing clamping member130with such rigidity or suitable stiffnesses for these purposes without undue experimentation.

Ends132of clamping member130, in various embodiments, may be configured for coupling with drive platforms110(or other structure supporting and positioning wheels111; for simplicity, such coupling will only be discussed in the context of being with drive platforms110). In some embodiments, ends132may be configured to detachably couple to drive platforms110, thereby allowing different clamping members130and/or different drive platforms110to be swapped in and out by the user. This modular configuration may allow a single robotic apparatus100to be used (and in many cases, optimized for such use) in different operating conditions, such as on various sized pipes (as shown inFIG.13A,FIG.13B,FIG.13C, andFIG.13D), various pipe orientations (e.g., increased clamping force to account for gravity when used on vertical pipes compared with horizontal pipes), and with different payloads.

Referring toFIG.14, in one embodiment, ends132of clamping member130may be shaped and dimensioned for coupling with a component of drive platform110having a complementary feature. Here, ends132have a key shape and each drive platform110has a similarly shaped and dimensioned keyhole recess121into which ends132are inserted. A friction fit or keyhole with the bottom closed off (not shown) may be sufficient to securely couple end132to drive platforms110in spite of the downward (towards pipe surface)-vectored clamping force, while in other embodiments, a coupler such as a screw may be used to provide a detachable coupling. In the embodiment shown inFIG.14, end132is provided with a hole133such that a screw may be used to securely couple clamping member130to drive platform110.

Clamping member130, in various embodiments, may be provided with a biasing mechanism135configured to adjust the amount of clamping force produced by clamping member130. In some embodiments, such as those in which clamping member130is rigid, clamping member130as a backstop against which to brace the biasing mechanism135while pushing the drive platforms110inwards towards pipe10to increase the clamping force. In other embodiments, such as those in which clamping member130is semi-rigid, biasing member135may be used to pull end132of clamping member130outwards (away from pipe10), thereby increasing the flex of clamping member130and thus the corresponding clamping force exerted by clamping member130. In both cases, reversing operation of biasing mechanism135can reduce the amount of clamping force exerted by clamping member130.

FIG.15shows one embodiment of biasing mechanism135in the form of an adjustment screw136. In this embodiment, adjustment screw136is inserted through a hole122in end cap117of drive platform110and into hole133in end132of clamping member130. As configured, if clamping member130is rigid, adjustment screw136can be turned to adjust the height of drive platform110relative to end132of clamping member130until drive platform110is pressing down firmly against the surface of pipe10. Clamping member130thus provides a reaction force against adjustment screw136such that the clamping force is vectored inwards towards pipe10. If clamping member130is semi-rigid, turning adjustment screw136causes end132to be pulled up towards drive platform110and away from pipe10, thereby increasing the flex of clamping member130and the corresponding clamping force exerted. In both cases, adjustment screw136can be turned in the other direction to reduce flex in the clamping member130and thereby reduce the clamping force.

In another embodiment, biasing mechanism135may comprise a compressed spring (not shown) situated between the bottom of end132and an upward-facing surface of drive platform110. As configured, if clamping member130is rigid, the bottom of end132of clamping member130provides a reaction force against the compressed spring such that end132pushes drive platform110down harder onto the surface of pipe.

Biasing mechanism135, in various embodiments, may be configured for manual and/or automated adjustment. Whether manual or automated, the ability to adjust the clamping force can prove very beneficial, allowing the robot to be adjusted for use on pipes of various diameters and orientations, and for use on uninsulated pipes and insulated pipes, without having to without changing out the clamping member130. Not only can such adjustments make the robotic apparatus100capable of operating under the changed conditions, such adjustments can also be made optimize certain performance factors. For example, the robotic apparatus100may not need as much clamping force to remain securely attached to a horizontal pipe10and thus it may be desirable to use a lesser clamping force when operating on horizontal pipes to optimize drag (and thus power consumption) and/or traverse pipe10at a higher speed, and then adjust to a higher clamping force when traversing vertical pipes10. Similarly, a user may wish to use a lesser clamping force when traversing an insulated pipe10so as to avoid damaging the insulation. Automated embodiments have the added benefit of being able to remotely adapt the robotic apparatus100to changing conditions rather than having to stop operation and perform adjustments manually.

Sensors & Other Payloads

FIG.16illustrates an embodiment of robotic apparatus100including a sensor assembly140. Sensor assembly140, in various embodiments, may be configured for any suitable purpose, such as for performing structural inspections of pipe10or tracking motion of robotic apparatus100on pipe10. Sensor assembly140, in various embodiments, may comprise sensor141and a support142. While only one sensor assembly140is shown, it should be recognized that robotic apparatus100may be equipped with any number of sensor assemblies in any suitable configurations.

Sensor141, in various embodiments, may include one of a variety of sensors suitable for inspecting or otherwise gathering information concerning pipe10and/or the surrounding environment. For example, in an embodiment, inspection sensor141may include an ultrasonic sensor or other sensor suitable for non-destructive inspection (NDI) of structural aspects of pipe10, such as measuring wall thickness or detecting cracks/corrosion. In another embodiment, inspection sensor141may include a sensor configured to sample air proximate to pipe10for traces of fluids (e.g., natural gas, oil) that may have leaked out of pipe10. Such traces may be indicative of cracks or corrosion in pipe10, and thus may be used for structural inspection purposes.

Sensor141, in various embodiments, may include one or more sensors used by robotic apparatus100to evaluate its operating environment and/or location therein. For example, sensor141may include one or more sensors configured to measure a diameter of pipe10, as shown and described in U.S. Pat. No. 11,154,989 entitled “Pipe Traversing Apparatus, Sensing, and Controls” and granted on Oct. 26, 2021, which is incorporated by reference herein in its entirety for all purposes. As another example, sensor141may include one or more sensors configured to track a location of robotic apparatus100on pipe10, as shown and described in the incorporated patent reference.

Support142, in various embodiments, may couple sensor141to robotic apparatus100and be moved to position sensor141relative to the surface of pipe10. Various embodiments of support142are shown and described in the context of the supports disclosed in the incorporated patent reference including, without limitation, the movable and spring loaded sensor support arms described therein.

One having ordinary skill in the art will recognize how to adapt such components for use on robotic apparatus100of the present disclosure without undue experimentation.

Sensor assembly140and other payloads can be attached to any suitable portion of robotic apparatus100, including on drive platforms110and/or on clamping member(s)130. The mounting location for sensor assembly(s)140may take into consideration the ease with which clamping member(s)130can be replaced, as well as trying to keep the center of mass of robotic apparatus100as close to the center of pipe10as possible to minimize the moment exerted by gravity on robotic apparatus100(especially when driving on horizontal pipes10).

Robotic apparatus100may also be provided with fail-safe arms, such as those shown and described in U.S. patent application Ser. No. 17/887,281 entitled “Radiography Inspection and Fail-Safe Mechanism for Pipe Traversing Robots” filed Aug. 12, 2022, which is incorporated herein in its entirety for all purposes. Such fail-safe arms may be adapted for use with robotic apparatus100hereof in any suitable manner including miniaturizing or making the fail-safe arms more compact to fit within a small clearance. Fail-safe arms can also be provided with different tracks of different lengths and/or curvature to fit different pipe sizes. These tracks may be modular, potentially by having the fail-safe mechanism mounted to the modular clamping member130of the appropriate size, or separately modular.

Traversing Pipeline and Avoiding Obstacles

In operation, robotic apparatus100may be mounted on an exterior surface of pipe10and traverse pipe10to deliver, perform, and/or support various functionalities, such as inspecting pipe10for structural defects or corrosion, and sampling the surrounding environment for traces of fluids that may have leaked from pipe10. In doing so, robotic apparatus100may at times need to reposition itself circumferentially on pipe10to, for example, navigate one or more obstacles extending from pipe10or to inspect a particular side(s) of pipe10. Similarly, at times it may be advantageous for robotic apparatus to corkscrew or otherwise follow a helical pattern about the exterior of pipe10when attempting to inspect the majority of the exterior of pipe10or the surrounding environment. Accordingly, robotic apparatus100of the present disclosure may be configured to traverse pipe10along straight, circumferential, and/or helical paths (and any combination thereof). Generally speaking, travel along these paths may be accomplished by driving wheels111in various combinations, as further described in more detail below.

In order to travel an axial pathway, all wheels are driven at the same speed, and wheels111having a first roller112orientation are driven in a first direction and wheels111having a second, mirrored roller112orientation are driven in a second, opposing direction. The first and second directions of rotation can be reversed to reverse the direction of axial travel.

FIG.17AandFIG.17Billustrate such a combination of wheel111motions for advancing the representative eight-wheeled robotic apparatus100ofFIG.6Aalong an axial pathway on pipe10. Because robotic apparatus100does not necessarily have a “front” and a “back” due to its symmetry, a front and rear have been arbitrarily assigned for ease of explanation. Wheels111a,111fhave right-handed roller orientation and as such are rotated counter-clockwise, as seen from the front, to generate traction along pipe10in a forward and counter-clockwise direction, as seen from the front. Conversely, wheels111b,111ehave left-handed roller orientation and as such are rotated clockwise, as seen from the front, to generate traction along pipe10in a forward and clockwise direction, as seen from the front. The clockwise and counter-clockwise vector components cancel each other out, resulting in axial motion in the forward direction.

In order to travel a circumferential pathway, all wheels are at the same speed, and wheels111are driven in the same direction. The direction of rotation can be reversed to reverse the direction of circumferential travel.

FIG.18AandFIG.18Billustrate such a combination of wheel111motions for advancing the representative eight-wheeled robotic apparatus100ofFIG.6Aalong circumferential pathway on pipe10. Because robotic apparatus100does not necessarily have a “front” and a “back” due to its symmetry, a front and rear have been arbitrarily assigned for ease of explanation. Wheels111a,111fhave right-handed roller orientation and as such are rotated counter-clockwise, as seen from the front, to generate traction along pipe10in a forward and counter-clockwise direction, as seen from the front. Conversely, wheels111b,111ehave left-handed roller orientation, and as such are rotated counter-clockwise, as seen from the front, to generate traction along pipe10in a rearward and counter-clockwise direction, as seen from the front. The forward and rearward vector components cancel each other out, resulting in circumferential motion in the rightward direction.

In order to travel a pathway having both axial and circumferential components, relative wheel speed and/or wheel rotation directions can varied as necessary to produce the desired vectors.

For example,FIG.19A,FIG.19B, andFIG.19Cillustrate a combination of motions suitable for causing robotic apparatus100to travel forward at a 45 degree angle with respect to the axis of pipe10that turns in a counter-clockwise direction as viewed from the front. Those wheels111having right-handed roller orientations are driven at the same speed as one another, and those wheels having left-handed roller orientations are not driven at all. The resultant traction vectors point forward and to the right at 45 degrees (assuming the rollers112are at 45 degree angles), and thus the robotic apparatus100travels a purely helical pathway that turns in a counter-clockwise direction as viewed from the front. Conversely, to travel a purely helical pathways that turns to the left, those wheels111having left-handed roller orientations are driven at the same speed as one another, and those wheels having right-handed roller orientations are not driven at all. The resultant traction vectors point forward and to the left at 45 degrees (assuming the rollers112are at 45 degree angles), and thus the robotic apparatus100travels a purely helical pathway that turns in a clockwise direction as viewed from the front. The respective directions of rotation can be reversed to cause the robotic apparatus100to travel backwards at 45 degree angle with respect to the axis of pipe10that turns in the corresponding direction.

In order to travel along a helical pathway that has shorter turns (i.e., smaller pitch) or longer terms (i.e., greater pitch), all wheels111may be driven, albeit with those of one handedness being rotated at a faster speed than those of the other handedness. Which handedness is driven faster versus which handedness is driven slower depends on the particular combination of wheel rotation directions being employed. Generally speaking, in order to travel a helical pathway with shorter turns (i.e., a greater circumferential component than axial component), one may choose to employ the wheel rotation configuration used for circumferential travel and vary wheel speed accordingly to achieve the desired smaller pitch. Likewise, in order to travel a helical pathway with longer turns (i.e., a greater axial component than circumferential component), one may choose to employ the wheel rotation configuration used for axial travel and vary wheel speed accordingly to achieve the desired smaller pitch.

Of course, robotic apparatus100of the present disclosure need not be constrained to travel along only axial, circumferential, and helical pathways—the principles described above can be combined as appropriate to move along any pathway on pipe10. Likewise, while the present disclosure may refer to all wheels111being driven (akin to all-wheel drive in an automobile), in embodiments having more than two wheels111, only two of such wheels111need be driven (akin to two-wheel drive in an automobile), noting that the two wheels111selected to be driven should be selected in accordance with the teachings above to produce the required resultant traction vector for a desired motion. The remaining wheels111can be free to rotate.

In operation, robotic apparatus100may be maneuvered along various pathways for a variety of purposes including, without limitation, to following a desired inspection pattern or to navigate around an obstacle on or near pipe10. As previously explained, in various embodiments, robotic apparatus100may be configured with an open side139through which a obstacle can pass without interference. Open side139, in various embodiments, is situated opposite clamping member130as shown.FIG.20A,FIG.20B,FIG.20C,FIG.20D, andFIG.20Eillustrate a representative approach for navigating past a pipe10′ situated very close to (i.e., so close that it would interfere with clamping member130and/or drive platforms110, despite the low profile configuration of robotic apparatus100) or even touching pipe10. InFIG.20AandFIG.20Brobotic apparatus100is approaching pipe10′. The open side139is not axially aligned with the area where pipe10′ abuts pipe10and thus, in robotic apparatus's100current orientation, pipe10′ may interfere with robotic apparatus100as it tries to pass pipe10′. InFIG.20Crobotic apparatus has maneuvered in a circumferential direction to align open side139with the area in which pipe10′ abuts pipe10. InFIG.20Drobotic apparatus100travels along an axial pathway to traverse where pipe10′ abuts pipe10.FIG.20Eillustrates robotic apparatus100having passed pipe10′.

FIG.21A,FIG.21B,FIG.21C,FIG.21D, andFIG.21Eillustrate a prototype of robotic apparatus100at various circumferential positions on a pipe10.FIG.21Bin particular shows open side139well.

FIG.22AandFIG.22Billustrate a combination of motions suitable for causing robotic apparatus100to recover from a radial slip condition. As used herein, the term radial slip refers to any slipping between wheels111and the pipe10that results in the robotic apparatus100exhibiting uncontrolled radial movement.

In order to recover from a radial slip condition, all wheels are driven towards the direction of recovery. In the embodiment shown, robotic apparatus100has undergone radial slip where its inner wheels have disengaged from pipe10. By rotating all wheels towards the direction of recovery, traction vectors are generated in the direction of recovery and axial components of such vectors cancel one another out. Wheel rotation speed and direction can be varied in accordance with the present disclosure to make adjustments if the radial slip is not symmetrical.

Robotic Sensing and Controls

Robotic apparatus100, in various embodiments, may include sensing and control capabilities similar to those shown and described in the “Robotic Sensing and Controls” section of the incorporated patent reference. One having ordinary skill in the art will recognize how to adapt such capabilities to robotic apparatus100of the present disclosure without undue experimentation.

Robotic Apparatus200

Embodiments of the present disclosure are further directed to a robotic apparatus200for traversing the exterior of piping systems, such as ones commonly found in chemical plants, power plants, manufacturing plants, and infrastructure. Like robotic apparatus100, various embodiments of robotic apparatus200clamps on to a pipe10, can drive in any direction along the surface of that pipe10, requires very low clearance around the pipe10, and fits on a large range of different pipe10sizes. Robotic apparatus200, in various embodiments, may have improved ability to drive over small obstacles on the pipe10(e.g., insulation bands), improved ability to drive past obstacles tangential to the pipe (e.g., a beam on which pipe10rests), and improved stability on large pipe10sizes.

High-Level Architecture

FIG.23is a perspective view of a representative embodiment of robotic apparatus200. Robotic apparatus200, in various embodiments, may generally include a center drive module210and one or more clamping drive modules220. Generally speaking, center drive module210and clamping drive module(s)220may include a plurality of wheels211,221powered by one or more motors215,225, respectively, to move and steer robotic apparatus200along pipe10, and each clamping drive module220may be configured to bias wheels211,221against pipe10to secure robotic apparatus200to pipe. While modules210,220may be referred to herein as “drive” modules, the present disclosure is not intended to be limited to embodiments in which all modules210,220, respectively, comprise motors215,225, nor to embodiments in which all or any particular combination of wheels211,221are powered. One having ordinary skill in the art will recognize appropriate configurations of powered/unpowered wheels211,221to effect the desired motion of robotic apparatus200on pipe10.

Embodiments of robotic apparatus200typically have numerous advantages over existing or alternative solutions, including:Clearance. The design is very compact compared to other pipe crawling robots. For example, the embodiment shown in the FIGS. requires no more than 2.4″ in any direction around pipe10. For comparison, the most compact robot on the market known to the inventors requires about 2.75″ of clearance. A big reason for this low clearance is the clamping drive module220design, where the clamping assembly230is custom made for specific pipe sizes. This allows a design that is much more compact compared to a robot design that is design to handle a large range of pipe sizes with the same parts.Low Weight. The design is also very lightweight. The design in the FIGS. weighs around 15 lbs. Similar to the clearance, the clamping drive module220design helps lower the weight of the robot as well. Since this robot does not rely on magnets to adhere to the pipe, it can avoid the weight associated with those.Maneuverability. Thanks to the driven wheels211,221, the robot can drive in any direction along the surface of the pipe, including purely axial or circumferential motion. Since there are no constraints on the direction of travel, the robot can drive in a straight line from its current position to any desired point on the surface of the pipe. This simplifies the control of the robot, improves its efficiency, and the ability to navigate different potential obstacles along the pipe.Large Range of Pipe Sizes. Thanks to the modular clamping drive modules220, the robot can be configured to fit on a large range of different pipe sizes (e.g., diameters between 4.5″ to 14″ for the example embodiment). One set of clamping drive modules220would be used for one specific pipe size, but with the optional adjustment mechanism235one set of clamping drive modules220could work with a range of pipe sizes. This would reduce the total number of different clamping drive modules220the operator would need in order to use the robot on any pipe size within the robot's full range. Additionally or alternatively, the modular design also allows the operator to swap out clamping drive modules220of various sizes to accommodate different pipe sizes.Vertical and Horizontal Pipes. This robot can drive on both horizontal and vertical pipes. Unlike some designs, that rely on gravity by balancing on the top of horizontal pipes, this robot uses a clamping force to attach to the pipe and can therefore drive on both vertical and horizontal pipes.Bare and Insulated Pipes. This robot can drive on both bare and insulated pipes. Unlike some designs, that rely on magnets to attach to the pipe, this robot uses a clamping force to attach to the pipe and can therefore drive on both bare and insulated pipes.Open Side to Pass Obstacles. This robot has an open side through which obstacles can pass as the robot traverses pipe10.
Center Drive Module210

FIG.24is a perspective view of a representative center drive module210. Center drive module210, in various embodiments, may generally include one or more wheels211powered by one or more motors215, which are similar to wheels111and motors125of robotic apparatus100, respectively. In the embodiment shown, center drive module210includes four independently-powered wheels211, with two wheels211a,211bmounted on a first end of frame213on a first side of center drive module210and two wheels211c,211dmounted to a second end of frame213on a second side of center drive module210. In some embodiments, frame213may be rigid while, in other embodiments, those “arm” portions to which wheels211are mounted may articulate up/down relative to the central portion and be biased (e.g., spring loaded) towards pipe10(i.e., downwards) to more effectively spread the resulting normal force, traction, and load more evenly between wheels211, as well as allow robotic apparatus200to drive over small obstacles on the surface of pipe10more easily.

Wheels211, in various embodiments, may be grouped into pairs in which the rollers212of one wheel211have an orientation mirroring that of the rollers212on the other wheel211. For example, in the four-wheeled embodiment of center drive module210shown inFIG.24, the orientation of rollers212aof wheel211amirrors that of the rollers212bof wheel211b, and the orientation of rollers212cof wheel211cmirrors that of the rollers212dof wheel211d. As with the similar mirrored-roller configuration of robotic apparatus100, travel along various paths on pipe10may be accomplished by driving wheels211(alone or in combination with wheels221) in various combinations, as further described in more detail below.

In various embodiments, such as that shown inFIG.24, the main rotation axis of each wheel211may be oriented to be perpendicular to a longitudinal axis of the pipe10when the robotic apparatus200is secured to pipe10(e.g., oriented in a lateral direction on frame213). Stated otherwise, wheels211are orientated such that they rotate in the direction of axial travel along pipe10, much like the wheels of a car rotate in the direction the car is heading on a road. Such a configuration tends to maintain more traction between wheel211and pipe10when driving over small obstacles on the surface of pipe10, such as insulation banding, compared with wheels oriented in a longitudinal direction on frame213, as the former can use the circular cross-section of the wheel211to gradually lift itself over an obstacle, whereas the latter has a rectangular cross-section in the direction of travel which does not tend to lift itself over obstacles.

In configurations where the main rotation axis of each wheel211is oriented to be perpendicular to a longitudinal axis of the pipe10when the robotic apparatus200is secured to pipe10(e.g., oriented in a lateral direction on frame213), wheels211are preferably mounted along a centerline of center drive module210such that wheels211contact pipe10at different longitudinal positions along a length of pipe10and at a common circumferential position about a circumference of pipe10, as shown. Positioning wheels211in such fashion helps ensure the main rotation axis of wheels211remains parallel to the contacted surface of pipe10, thereby maximizing the contact area between wheels211and the surface of pipe10. Conversely, were wheels211to be circumferentially offset from one another the main rotation axis of wheels211not being directly parallel with the contacted surface of pipe10, causing wheel211to partially ride along its “rim” and thus reducing the contact area between the wheels211and the surface of pipe10. This is illustrated inFIG.8.

In an alternative embodiment (not shown), the main rotation axis of each wheel211may instead be oriented to be parallel with a longitudinal axis of pipe10(e.g., in a longitudinal direction on frame213). Stated otherwise, wheels211are orientated such that they rotate in the direction of circumferential travel along pipe10. Such a configuration tends to maintain more traction between wheel211and pipe10when driving in a circumferential direction about pipe10, but may experience reduced traction when travelling over small obstacles on the surface of pipe10, such as insulation banding, for reasons similar to those explained above. In such a configuration, wheels211are preferably mounted off the centerline of center drive module210such that wheels211contact pipe10at different circumferential positions about a circumference of pipe10. This circumferential spacing between wheels211of a given pair can provide extra stability to robotic apparatus200on pipe10since the clamping force can be applied from four directions, compared with three. The circumferentially-offset wheels211of a given pair may be arranged at a common longitudinal position on pipe10.

Various electronics217may be mounted on a center portion of frame213between the two sets of wheels211. For example, electronics217may contain components for operating robotic apparatus200, such as a circuit board with a controller configured to actuate motors215,225in accordance with executable instructions stored on a memory component. In some embodiments, payload(s) may be carried on one or more drive platforms110, on frame113, or on any other suitable location on robotic apparatus100. Of course, robotic apparatus100could additionally or alternatively be powered via a power cord or other suitable power source in various embodiments.

Clamping Drive Module220

FIG.25AandFIG.25Bare perspective views of representative clamping drive modules220for use on small diameter pipes and large diameter pipes, respectively. Clamping drive module220may generally include two or more wheels221powered by two or more motors225, as well as a clamping assembly230. Generally speaking, clamping drive module220is sized and shaped to wrap around a portion of the circumference of pipe10. Similar to clamping member130of robotic apparatus100, clamping assembly230may be configured to apply a force for urging wheels211,221towards an outer surface of pipe10for securing robotic apparatus200to pipe10. Here though, clamping drive module220may be configured to position wheels221not on directly opposing sides of pipe10, but rather closer together than that—preferably in a manner that forms a triangle-like arrangement with wheels211about the circumference of pipe10when robotic apparatus200is viewed head-on such that the normal forces applied by the circumferentially offset wheels balance to provide stability and secure robotic apparatus200to pipe10, as later shown inFIG.26.

Still referring toFIG.25AandFIG.25B, clamping assembly230, in various embodiments, many comprise a static member231and two articulating arm members232. Static member231may rigidly attach to center drive module210(e.g., with wheels211contacting pipe10somewhere on its top third) and articulating arm members232may extend around opposing sides of pipe10(e.g., such that wheels221contact pipe10somewhere on its bottom two thirds, respectively, to provide mechanical stability). Static member231and articulating arm members232may be rotatably coupled so as to form articulated joints between static member231and each of articulating arm members232. Biasing members233, such as a torsion spring, may be configured to apply a force that urges each articulating arm232towards pipe10. The torque should be tuned such that the resulting normal forces on wheels221are sufficient (based on the coefficient of friction) for wheels221to get traction and not slip on pipe10. However, an excessive torque can start to deform some insulation materials that are commonly used on industrial piping (such as mineral wool), place excessive loads on various structural parts of robotic apparatus200, and or increase the power required to drive robotic apparatus200along pipe10. As configured, clamping assembly230“hugs” pipe10, pulling wheels221and wheels211against pipe10to secure clamping drive module220and center drive module to pipe10. Notably, in various embodiments, clamping drive module220does not fully circumscribe pipe10, but rather leaves an open side239opposite center drive module210through which obstacles can pass as robotic apparatus200traverses pipe10, as later shown inFIG.27andFIG.28.

Referring toFIG.25B, articulating arm members232may be adjustable in length in some embodiments. In one such embodiment, articulating arm member232may be comprised of a first member233and a second member234, and coupled together by an adjustable coupler235such as the slot-and-screw coupler shown. For a shorter articulating arm member232, the screw can be loosened and second member234moved upwards so as to increase an amount of overlap between a proximal end of second member234and a distal end of first member233, whereupon the screw can be retightened. Conversely, for a longer articulating arm member232, the screw can be loosened and second member234moved downwards so as to decrease an amount of overlap between a proximal end of second member234and a distal end of first member233, whereupon the screw can be retightened. These lengthwise adjustments can be made to help fit the specific pipe size optimally.

FIGS.27A-27Eillustrate embodiments of robotic apparatus200on various sizes of pipes10ranging from 4.5″ inFIG.27ATO 11.5″ inFIG.27E. Robotic apparatus200, in various embodiments, has a modular configuration in which a given clamping drive modules220can be detached from center drive module210and replaced with a different sized clamping drive module220, thereby allowing robotic apparatus200to operate on pipes10of various sizes. For example, a small clamping drive module220is shown in use on the smaller pipe ofFIG.27Awhereas a large clamping drive module220is shown in use on the larger pipe ofFIG.27E. Generally speaking, an appropriate sized clamping drive module220may have a static member231and articulating arm members232of similar or slightly larger radius of curvature as that of pipe10, and articulating arm members232may have a length configured to position wheels221in the arrangement previously described. It is generally not desirable to use a larger clamping drive module220than necessary, as the extra size will increase the amount of clearance around pipe10necessary for robotic apparatus200to traverse pipe10without interference from nearby obstacles, potentially reduce the size of open side239, and potentially position wheels221unfavorably from a stability standpoint.

Additionally or alternatively, robotic apparatus200, in various embodiments, has a modular configuration in the sense that articulating arm members232can be lengthened or shortened to accommodate various pipe sizes. One set of clamping drive modules220would be used for one specific pipe size, but with the optional adjustment mechanism235one set of clamping drive modules220could work with a range of pipe sizes. This would reduce the total number of different clamping drive modules220the operator would need in order to use the robot on any pipe size within the robot's full range.

In various embodiments, the rollers222of one wheel221on a given clamping drive module220may have the same orientation as the rollers222of the other wheel221, as shown. In various other embodiments, the rollers222of one wheel221on a given clamping drive module220may have an orientation mirroring that of the rollers222on the other wheel221. Travel along various paths on pipe10may be accomplished by driving wheels221(alone or in combination with wheels211) in various combinations, as further described in more detail below.

In various embodiments, such as those shown inFIG.25AandFIG.25B, the main rotation axis of each wheel221may be oriented parallel to the longitudinal axis of pipe10. Stated otherwise, wheels221are orientated such that they rotate in the direction of circumferential travel along pipe10. Positioning wheels211in such fashion ensures the entire width of wheel221contacts pipe10, thereby ensuring traction along the circumferential direction of pipe10under all conditions. Conversely, were the main rotation axis of wheels221to be oriented perpendicular to the longitudinal axis of pipe10, a mismatch in the length of articulating clamping arms232and the diameter of pipe10may result in the main rotation axis of wheels221not being directly parallel with the contacted surface of pipe10, causing wheel221to partially ride along its “rim” and thus reducing the contact area between the wheels221and the surface of pipe10.

In an alternative embodiment (not shown), the main rotation axis of each wheel221may instead be oriented perpendicular to the longitudinal axis of pipe10. Stated otherwise, wheels221are orientated such that they rotate in the direction of axial travel along pipe10. Such a configuration tends to maintain more traction between wheel221and pipe10when driving in an axial direction along pipe10and thus does well when travelling over small obstacles on the surface of pipe10, such as insulation banding, for reasons similar to those explained above. That said, as explained above, such a configuration requires a precise match between the length of articulating clamping arms232and the diameter of pipe10to ensure uniform contact across the width of wheel221rather than wheel221partially riding along its “rim”.

FIG.29is a perspective view of a representative embodiment of robotic apparatus200on a pipe10. In this preferred embodiment, the main rotation axis of wheels211of center drive module210are oriented perpendicular to the longitudinal axis of pipe10such that they rotate in the direction of axial travel along pipe10, and the main rotation axis of wheels221of clamping drive module220are oriented parallel to the longitudinal axis of pipe10such that they rotate in the direction of circumferential travel along pipe10. This particular combination ensures good traction in both the axial and circumferential directions, with center drive module210providing the best traction for travel in the axial direction and clamping drive modules220providing the best traction for travel in the circumferential direction. Notably, neither suffers from mismatch issues which may cause its respective wheels to ride on their rims or otherwise not have uniform contact across the entire width of the wheel.

Various payloads can optionally be added to robotic apparatus200(in some embodiments, on clamping drive module220) to enable robotic apparatus200to perform different tasks. Such payloads can be attached to either end of robotic apparatus200. For example,FIG.29shows a probe attached to a clamping member220. Representative payloads include, without limitation, cameras and non-destructive inspection equipment such as pulsed eddy current equipment and ultrasonic testing equipment.

Traversing Pipeline and Avoiding Obstacles

FIG.31A,FIG.32A, andFIG.33Ashow the directions that the wheels211,221need to be driven, for the exemplary embodiment ofFIG.29having a center drive module and two clamping drive modules, to drive the whole robotic apparatus axially, circumferentially or helically around the pipe, respectively.

Referring first toFIG.31A, robotic apparatus200may be advanced in an axial direction by (i) simultaneously rotating, at equal speeds, wheels211a,211b,211c,211din the same direction as one another, and (ii) simultaneously rotating, at equal speeds, wheels221a,221bin a first direction and wheels221c,221din a second, opposing direction. Of course, this example assumes all wheels211,221are powered. In various embodiments, fewer than all of the wheels211,221may be powered yet robotic apparatus200can still be advanced in an axial direction. For example, in some embodiments, wheels211a,211bmay be powered and wheels211c,211dmay be unpowered, or vice versa; in either case, the opposite-handedness of the rollers212of either pair ensures that robotic apparatus200is advanced in an axial direction. Likewise, in some embodiments, only one wheel of pair221a,221band only one wheel of pair221c,221dmay be powered. Many different combinations of powered vs. non-powered wheels can be implemented to advance robotic apparatus200in an axial direction. One of ordinary skill in the art can deduce how the wheel driving directions need to change if any wheel handedness (left-hand or right-hand) or wheel orientation changes based on the teachings of the present disclosure.

Referring toFIG.32A, robotic apparatus200may be advanced in an circumferential direction by (i) simultaneously rotating, at equal speeds, (a) wheels211a,211bin opposing direction, (b) wheels211c,211din opposing directions; and (ii) simultaneously rotating, at equal speeds, wheels221a,221b,221c,221din the same direction as one another. Of course, this example assumes all wheels211,221are powered. In various embodiments, fewer than all of the wheels211,221may be powered yet robotic apparatus200can still be advanced in a circumferential direction. One of ordinary skill in the art can deduce how the wheel driving directions need to change if any wheel handedness (left-hand or right-hand) or wheel orientation changes based on the teachings of the present disclosure.

Referring toFIG.33A, robotic apparatus200may be advanced in an helical direction by (i) simultaneously rotating, at equal speeds, wheels211a,211cin the same direction as one another, and (ii) simultaneously rotating, at equal speeds, wheels221a,221bin the same direction as one another. Here, wheels211b,211d, and221c,221dmay be allowed to freely rotate, as shown. In various embodiments, fewer than all of the wheels211,221may be powered yet robotic apparatus200can still be advanced in a circumferential direction. One of ordinary skill in the art can deduce how the wheel driving directions need to change if any wheel handedness (left-hand or right-hand) or wheel orientation changes based on the teachings of the present disclosure.

FIG.31B,FIG.32B, andFIG.33Bshow the directions that the wheels211,221need to be driven, for the another exemplary embodiment similar to that ofFIG.29but having a center drive module and only one clamping drive module, to drive the whole robotic apparatus axially, circumferentially or helically around the pipe, respectively.

Referring first toFIG.31B, robotic apparatus200may be advanced in an axial direction by (i) simultaneously rotating, at equal speeds, wheels211a,211bin the same direction as one another, and (ii) simultaneously rotating, at equal speeds, wheels221a,221bin opposing directions. Referring toFIG.32B, robotic apparatus200may be advanced in an circumferential direction by (i) simultaneously rotating, at equal speeds, wheels211a,211bin opposing directions, and (ii) simultaneously rotating, at equal speeds, wheels221a,221bin the same direction as one another. Referring toFIG.33C, robotic apparatus200may be advanced in an helical direction by (i) rotating wheel211ain a first direction, and (ii) simultaneously rotating, at equal speeds, wheels221a,221bin the same direction as one another. One of ordinary skill in the art can deduce how the wheel driving directions need to change if any wheel handedness (left-hand or right-hand) or wheel orientation changes based on the teachings of the present disclosure.

Furthermore, it should be recognized that, when advancing robotic apparatus200in along a helical pathway, the pitch of the helical pathway may be determined based on the rotation speeds of wheels211relative to the rotation speeds of wheels221. For example, rotating wheels221faster may impart a tighter pitch while rotating wheels221slower may impart a looser pitch.

Robotic Sensing and Controls

Robotic apparatus200, in various embodiments, may include sensing and control capabilities similar to those shown and described in the “Robotic Sensing and Controls” section of the incorporated patent reference. One having ordinary skill in the art will recognize how to adapt such capabilities to robotic apparatus200of the present disclosure without undue experimentation.

Additional Components

FIG.34AandFIG.34Billustrate side perspective and front perspective views of another embodiment of robotic apparatus200on a large diameter pipe10. Generally speaking, this particular embodiment of robotic apparatus200is similar in architecture to previously described embodiments, but may contain one or combination of additional components such as additional covers214for wheels211, a handle216, additional wheels221, bumper wheels223, one or more stiffening rods2264, a sensor payload240, a camera244, one or more encoder wheels246, fail safe assemblies250, and spring-loaded assembly260for wheels211. While the present embodiment is shown as equipped with all of these components, the present disclosure is not intended to be limited to such a fully-equipped embodiment; rather, one of ordinary skill in the art will recognize that various embodiments of robotic apparatus200may include one or a combination of any of such components.FIG.35shows a similar embodiment of robotic apparatus200on a smaller diameter pipe10.

Additional Wheels221′

As best shown inFIG.34A, robotic apparatus200, in various embodiments, may further comprise additional wheels221′ on clamping drive module220. Additional wheels221′ may be mounted in close proximity to wheels221, at the same or similar circumferential position so as to ensure good contact with pipe10and to balance the normal force (due to clamping) evenly between wheels221and wheels221′. In the embodiment shown, wheels221′ are mounted at axially offset positions from wheels221towards a center of robotic apparatus200so as to not increase the overall length of robotic apparatus200. To the extent wheels221have angled rollers222, the rollers222′ of wheels221′ may mirror the orientation of rollers222of an adjacent wheel221, as shown. Adding additional wheels221′ may have the following benefits:

(1) Decreasing localized pressure on surface of pipe10. A relatively high clamping force may be required to produce enough traction between the wheels221and the pipe10, e.g. when the robot200is lifting its own weight (and the weight of a potential cable) driving up a vertical pipe10. If that clamping force is divided between more wheels (e.g., amongst wheels221,221′) the pressure from each wheel decreases and the robot200is less likely to damage the pipe10—e.g. dent the jacketing of an insulated pipe.

(2) Cancellation of undesired forces. Undesired forces are cancelled out locally and thus there is less twisting and bending of the structural parts of the robotic apparatus200. Wheels221with angled rollers222may work in pairs and together they can provide a force in any desired direction along the surface of pipe10, in part by cancelling out forces in undesired directions. However, if the pair of wheels221are located at opposite ends of the robotic apparatus200, the structure in between the wheels221may bend and twist as it transfers those loads. When a pair of wheels221,221′ are mounted close to each other, the structure between them tends to not deform as much since the lever arms are shorter and the connecting structure can be stiffer.

(3) Greater thrust. More driving wheels allow for greater thrust. If the thrust of robotic apparatus200is not limited by traction, the maximum thrust (force) the robotic apparatus200can exert as it drives will depend on the maximum torque of each drive wheel221and the number of drive wheels221. If powered (e.g., by motors225′, not shown), wheels221′ allow robotic apparatus200to exert more thrust.

Bumper Wheels223

Still referring toFIG.34A, embodiments of robotic apparatus200may include, on each clamping drive module220, two freely-spinning bumper wheels223having freely-spinning rollers224. In an ideal scenario, with identical biasing forces (e.g., from biasing members233) and no friction, arm members232should self-center on the pipe10by actuating the two pivot points at the respective junctures of articulating arm members232and static member231by an equal amount. However, in reality, the robotic apparatus possibly could shift to one side without self-centering, which decreases the amount of clearance on the inside of the robotic apparatus200to the point where the robotic apparatus200may start to scrape against the pipe10. Bumper wheels223, in various embodiments, may serve to mitigate the effect of any side-to-side shifting by contacting and rolling along pipe10when such shifting occurs. The exact distance from the pipe10to the surface of bumper wheels223can be adjusted such that bumper wheels223do not touch the pipe10when robotic apparatus200is properly centered, but if the robotic apparatus200starts to shift side-to-side, then bumper wheels223will contact pipe10and ensure that a certain amount of clearance remains between the articulating arm members232and the surface of the pipe10. In the embodiment shown, bumper wheels223has rollers224having rotation axes oriented perpendicular to the main axis of rotation of the main wheel portion (an “omniwheel” design) so that bumper wheels223may move freely both axially and circumferentially along pipe10without adding significant friction.

Fail-Safe Assembly250

Robotic apparatus200may also be provided with fail-safe arms, such as those shown and described in the U.S. patent application Ser. No. 17/887,281 entitled “Radiography Inspection and Fail-Safe Mechanism for Pipe Traversing Robots” filed Aug. 12, 2022, which is incorporated herein in its entirety for all purposes. Such fail-safe arms may be adapted for use with robotic apparatus200hereof in any suitable manner including miniaturizing or making the fail-safe arms more compact to fit within a small clearance. Fail-safe arms can also be provided with different tracks of different lengths and/or curvature to fit different pipe sizes.

FIG.36A,FIG.36B, andFIG.36Cillustrate representative fail-safe mechanisms250for robotic apparatus200. Fail-safe mechanism250, in various embodiments, may comprise a curved arm252, a guide254, and a motor256configured to advance and retract curved arm252through guide254. As shown, guide254, in various embodiments, may comprise three rotational elements positioned to guide curved arm252along an intended pathway. The rotational elements are on the inside of the curved arm252which has interior surfaces designed for the bearing and spur gear to move against. This allowed for a more compact design. Movement of arm252may be driven by motor256, e.g. via a spur gear configured to mate with a toothed track of curved arm252. Similar to embodiments of clamping assembly230, the dimensions and curvature of arm252may be selected to complement a diameter of pipe10on which robotic apparatus200will be secured. In an embodiment, fail-safe mechanism250may be considered part of the associated clamping drive module220such that, in order to switch to a significantly smaller or larger pipe10, the user only needs to switch out the clamping drive module(s)220and they will automatically have the correctly sized fail-safe arms252already attached.

FIG.37shows an embodiment of robotic apparatus200having fail-safe mechanisms250affixed to each clamping drive module220thereof. The fail-safe mechanisms250on the left side of the figure are shown in a closed configuration, while the fail-safe mechanisms250on the right side of the figure are shown in an open configuration. Generally speaking, fail-safe mechanisms250are closed when traversing pipe10so as to prevent robotic apparatus200from falling off in the event it slips; however, fail-safe mechanisms250can be opened when traversing an obstacle such that the obstacle can pass through the open side of robotic apparatus200.

Spring-Loaded Wheel Assembly260

FIG.38illustrates a perspective view of a spring-loaded assembly260for biasing a subset of wheels211of center drive module210towards the surface of pipe10. Instead of mounting all wheels211rigidly to frame213of center drive module210, spring-loaded wheel assembly260may be included to bias a subset of wheels211(here, two of the four wheels211) against pipe10, thereby allowing the biased wheels211to travel downwards and upwards relative to the surface of pipe10. Biasing a subset of wheels211ensures that all wheels211stay in contact with pipe10even as robotic apparatus200traverses over obstacles or drives over an uneven surface, thereby improving traction. In some embodiments, it may be preferable to bias only a subset of wheels211so as to maintain a certain distance between the center drive module210and pipe10. This could be achieved by biasing all wheels211; however, such a configuration would require very accurate balancing against the biasing forces generated by clamping drive module220for all pipe sizes. In the example shown, the two outermost wheels211are rigidly mounted and dictate the distance to the pipe10. The two innermost wheels211are biased using spring-loaded wheel assembly260because it tends to keep the center drive module210more stable and decreases the amount of tilting due to obstacles and uneven surfaces. The biasing forces may be selected based on the anticipated normal force, which depends on the clamping force from clamping modules220. The normal force from center drive module220may should ideally be evenly distributed between the four wheels211to enable a high overall clamping force without causing excessive pressure from an individual wheel211that can damage the pipe.

Spring-loaded assembly260may be coupled to frame213or share components of frame213. Spring-loaded assembly260, in various embodiments, may generally comprise a static member261and a travelling member262there below, separated by a biasing member263such as a spring. Wheel211may be mounted to travelling member262and, as configured, biasing member pushes off of static member to push travelling member262—and thus wheel211—towards the surface of pipe10. Travelling member262, in various embodiments, may be mounted on a track265or other structure configured to guide the movement of travelling member262in an up and down direction (i.e., radially relative to pipe10). One or ordinary skill in the art will recognize, based on the teachings of the present disclosure, alternative mechanisms capably of biasing certain wheels211toward the surface of pipe10and the present disclosure is not intended to be limited to any particular embodiment.

Encoder Wheels246

FIG.39AandFIG.39Billustrate first and second encoder wheels246configured to track the circumferential and axial motion of robotic apparatus200on pipe10, respectively. The encoder wheel246ofFIG.39Ais mounted with its main rotation axis parallel to the longitudinal axis of pipe10such that this encoder wheel246rotates when moving circumferentially about pipe10. Conversely, the encoder wheel246ofFIG.39Bis mounted with its main rotation axis perpendicular to the longitudinal axis of pipe10such that this encoder wheel246rotates when moving axially along pipe10. Encoder wheels measure the number of times the wheel rotates and thus distance travelled in a particular direction can be calculated based on the known diameter of the encoder wheel. In various embodiments, encoder wheels246may be coupled to center drive module210(e.g., to frame213thereof, as shown) rather than to clamping module(s)220such that they remain when swapping out clamping drive modules220.

Encoder wheels246each include a plurality of rollers247about a circumference of the main wheel along the contact surface. In the embodiment shown, rollers247rotate in a direction perpendicular to the direction of rotation of the main wheel portion (e.g., an “omniwheel” design), thereby allowing encoder wheels246to slide along the surface of pipe10with minimal friction in a direction not necessarily aligned with the direction of rotation of the main wheel portion. In various embodiments, encoder wheels246may have conical endcaps, as shown, so that the overall shape of the encoder wheel246approximates a bicone. The sloped sides of these endcaps act as ramps and ease the transition over various obstacles along the pipe surface.

Encoder wheels246, in various embodiments, may comprise a biasing mechanism (e.g., torsional spring and hinge, as shown)248for biasing encoder wheels246towards the surface of pipe10. Biasing encoder wheels246in this manner ensures good contact between encoder wheels246and the surface of pipe10within the full range of pipe sizes that the robotic apparatus200was designed for.

Miscellaneous

Referring back toFIG.34A,FIG.34B, andFIG.34C, a camera244, in various embodiments, may be mounted to one side of robotic apparatus200—e.g., on the opposing side of robotic apparatus200on which sensor240is mounted. Camera244, in an embodiment, may point in an axial direction along pipe10so as to help a user (or automated control system with computer vision) navigate as it traverses pipe10. In an embodiment, a mirror can be mounted at the end of the camera to redirect the field of view to look down at the surface of pipe10.

Robotic apparatus200, in various embodiments, may additionally or alternatively comprise one or more stiffening rods226. Stiffening rods226may extend between and connect clamping drive modules220, and serve to increase the stiffness of the overall structure of robotic apparatus200and thereby minimize bending of clamping drive modules220under various loads. In the embodiment shown, stiffening rods226extend between the distal ends of static members231of clamping assemblies230such that each is circumferentially offset from center drive module210so as to better counteract bending moments on clamping assemblies230. The ends of stiffening rods226may be detachable from clamping assemblies230such that clamping drive modules220can be easily swapped in and out. Stiffening rods226, in various embodiments, may also serve as handles for carrying robotic apparatus200and/or manipulating robotic apparatus200during installation on pipe10.

Robotic apparatus200, in various embodiments, may additionally or alternatively comprise covers214for covering wheels211of center drive module210. These covers214can help protect cables and improve aesthetics of robotic apparatus200.

Robotic apparatus200, in various embodiments, may additionally or alternatively comprise one or more handles216for carrying robotic apparatus200and/or manipulating robotic apparatus200during installation on pipe10. While only one can be seen, robotic apparatus200may comprise two handles216—one on each end of center drive module210.

FIG.40shows a prototype of robotic apparatus200on a vertical pipe10.

Although the present disclosure and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the disclosure as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present disclosure. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.