Abstract:
Inspection devices nondestructively sense component shape and integrity such as through ultrasonic sensors. Inspection devices include a positional determinator to give orientation of devices relative to the tested object. True distances and relative boundaries of the object are determined with testing and orientation data regardless of rigid or known inspection device position. Inspection data can be corrected for refraction knowing distances and object boundaries. Inspection devices can include additional inspection components like cameras and lighting to match visual inspection with nondestructive testing data spatially and temporally. Inspection devices can be used with self- or manual-propulsion in a working environment with the inspection object. Inspection devices use an operator or computer processor, local or remotely-connected power sources, and communications structures to power and operate the devices.

Description:
BACKGROUND 
     Ultrasonic testing allows non-destructive verification of surfaces and interiors of various structures whose integrity may be important for operations and safety. Non-destructive testing is used throughout construction, power generation, and aeronautics industries in both manufacture/fabrication and during life of use, where various testing protocols and devices are used during maintenance, at set intervals, or following operations-impacting events. Ultrasonic testing in particular can be used by portable devices that use acoustic signals to determine a tested structure&#39;s integrity, shape, internal configuration, etc. 
       FIG. 1  is an illustration of data that can be returned by an ultrasonic sensor that emits a discreet acoustic signal and detects its reflection in a tested structure. For example, the ultrasonic device may be a submerged sensor emitting acoustic signals, or pings, of a detectable frequency and amplitude in water that bounce off a tested object, such as a pipe wall or boat hull, also submerged. As shown in  FIG. 1 , the ultrasonic device may emit a ping at t=0, detected at first peak  10 . A portion of the ping may bounce off a front wall of the tested structure and be detected later at t=2 at a second peak  20  upon returning to the sensor. Another portion of the ping may pass through the front wall of the tested structure to a back wall, where it is reflected back and detected at t=6.5 at a third peak  30 . By comparing the different times and amplitudes between peaks  20  and  30 , a user or program may determine the thickness of the wall using the known speed of the sound through the structure and water. By emitting and sensing ultrasonic pings with such a device in  FIG. 1  at several different locations, a user or program can compare variations in wall thickness and detect potential abnormalities such as voids or cracks, as well as verify structure positioning and size, like a weld or wall position and depth. 
     Non-destructive testing can also include visual inspection, non-visual electromagnetic inspection (like x-ray inspection), radiographic inspection with beta radiation, magnetic resonance inspection, etc. In such testing, each result typically must be paired with a relatively accurate location of the tested structure in order to verify integrity and dimensions as expected locations as well as give accurate position of detected anomalies. Where a tested structure is inaccessible or difficult to visualize by a human operator or visually-verifying program, indirect methods of verifying tested structure location can be used. For example, a testing probe may be locked on a set of tracks at known positions to verify probe position and then verify tested structure position. Or a testing probe may be positioned at verifiable locations via RFID or optical tags to derive tested structure position. Still further, visual analysis, such as KLT stabilization, can be used to identify high contrast areas, shapes, and edges in order to approximate probe position from an image. 
     SUMMARY 
     Example embodiments include probes that can sense component shape and integrity without destroying the same by receiving reflected energy from the component that indicates the same. For example, a probe may include an ultrasonic sensor capable of receiving vibrational energy reflected from a test subject. The probe further includes a positional element to orient the probe relative to the object such that true distances and relative boundaries of the object can be determined. Through example methods, a processor or user may know true position of a probe and ultrasonic data with respect to an inspection subject without strict positional controls. An example embodiment probe can also include a video capture device, like a camera, to match visual inspection with nondestructive testing data by both true position and at same times. An example embodiment probe may also include a drive, like a propeller or jet or wheels or manual rod for user grappling, to move the probe freely about inspected objects without strict regard for position. A computer processor, and local power sources and wireless communications transceivers, and/or external power hookups and communications cables, can be used in example embodiment probes to power and operate the same, potentially remotely by users stationed in areas distant or unreachable from the inspected objects. 
     Example methods include receiving nondestructive testing data, like ultrasonic waves emitted and reflected back to an emitter and receiver, in a medium along with positional data of the receiver. Using the data, a closest point and orientation and distance of the point from the tester can be calculated. Testing may then iteratively advance to farther points from the determined closest point to map out a surface of the tested object. The nondestructive testing data may then be corrected where it falls at an interior of the object and thus refracts, and accurate position of all testing data may be known with respect to an object being tested, without a controlled, previously-known set position of a testing device and object being tested. The testing data and positional data may also be accurately paired with visual inspection data to give comprehensive, accurate visual and positional testing results 
    
    
     
       BRIEF DESCRIPTIONS OF THE DRAWINGS 
       Example embodiments will become more apparent by describing, in detail, the attached drawings, wherein like elements are represented by like reference numerals, which are given by way of illustration only and thus do not limit the terms which they depict. 
         FIG. 1  is an illustration of a related art ultrasonic testing output. 
         FIG. 2  is an illustration of an example embodiment nondestructive testing device. 
         FIG. 3  is a flowchart of an example method of nondestructive testing. 
         FIG. 4  is an illustration of an example embodiment nondestructive testing device in use with example methods. 
     
    
    
     DETAILED DESCRIPTION 
     This is a patent document, and general broad rules of construction should be applied when reading and understanding it. Everything described and shown in this document is an example of subject matter falling within the scope of the appended claims. Any specific structural and functional details disclosed herein are merely for purposes of describing how to make and use example embodiments or methods. Several different embodiments not specifically disclosed herein fall within the claim scope; as such, the claims may be embodied in many alternate forms and should not be construed as limited to only example embodiments set forth herein. 
     It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. 
     It will be understood that when an element is referred to as being “connected,” “coupled,” “mated,” “attached,” or “fixed” to another element, it can be directly connected or coupled to the other element or intervening elements may be present. In contrast, when an element is referred to as being “directly connected” or “directly coupled” to another element, there are no intervening elements present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between”, “adjacent” versus “directly adjacent”, etc.). Similarly, a term such as “communicatively connected” includes all variations of information exchange routes between two devices, including intermediary devices, networks, etc., connected wirelessly or not. 
     As used herein, the singular forms “a”, “an” and “the” are intended to include both the singular and plural forms, unless the language explicitly indicates otherwise with words like “only,” “single,” and/or “one.” It will be further understood that the terms “comprises”, “comprising,”, “includes” and/or “including”, when used herein, specify the presence of stated features, steps, operations, elements, ideas, and/or components, but do not themselves preclude the presence or addition of one or more other features, steps, operations, elements, components, ideas, and/or groups thereof. 
     It should also be noted that the structures and operations discussed below may occur out of the order described and/or noted in the figures. For example, two operations and/or figures shown in succession may in fact be executed concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved. Similarly, individual operations within example methods described below may be executed repetitively, individually or sequentially, so as to provide looping or other series of operations aside from the single operations described below. It should be presumed that any embodiment having features and functionality described below, in any workable combination, falls within the scope of example embodiments. 
     The inventors have recognized that existing nondestructive testing devices often require stringent positional controls in order to properly correlate testing data with visual data and tested object location. These positional controls, like tracks, targets, RFID tags, and other equipment often require additional installation and encumber inspections in remote locations, like underwater. Moreover, strict positional controls often limit the degree to which inspections can be conducted, because a testing device cannot be freely moved to areas of interest while maintaining positional control or verification. To overcome these newly-recognized problems as well as others, the inventor has developed systems and methods that provide reliable and additional positional data during nondestructive testing such that strict positional controls may be reduced or forgone entirely. This may permit faster and less equipment-intensive installation and maintenance, as well as improve speed and flexibility in nondestructive testing. 
     The present invention is a nondestructive testing device that includes a positional element and uses testing data to determine relative locations without rigid position control or locking. In contrast to the present invention, the few example embodiments and example methods discussed below illustrate just a subset of the variety of different configurations that can be used as and/or in connection with the present invention. 
       FIG. 2  is an illustration of an example embodiment nondestructive inspection device  100  useable in a variety of environments, including in submerged nuclear reactor environments. As shown in  FIG. 2 , example embodiment device  100  includes an ultrasonic tester  110  that may include an ultrasonic emitter and/or sensor that uses ultrasonic vibration to detect object position within a fluid medium as well as density/material changes within objects. For example, ultrasonic tester  110  may include an ultrasonic emitter capable of emitting ultrasonic bursts  111  in frequencies and amplitudes carried by common working mediums like light or heavy water and air, as well as at least partially reflectable by denser solids. Individual bursts  111  may return data like that seen in  FIG. 1  when incident on an inspection object  50 , which are receivable by tester  110 . 
     Ultrasonic tester  110  may be capable of emitting and detecting in several directions and/or in rapid sequence. For example, as shown in  FIG. 2 , tester  110  may emit one or more ultrasonic bursts  111  toward an object  50  to be tested. Similarly, tester  110  may be an ultrasonic phased array matrix that sequentially or simultaneously emits several bursts  111  in known orientations, angles, and/or relative positioning with respect to one another. A phased array matrix may also include matching sensors that can detect and discriminate among return bursts reflected from an object  50 . A phased array matrix may also focus bursts  111  at various planes by projecting at varying pitches and angles, such that a field of emitted ultrasonic bursts  111  form an impingement field or grid at various distances and densities on object  50 . Examples of phased array matrix devices that can be adapted for use as ultrasonic tester  110  include those found in US Patent Publication 2014/0060196 to FALTER et al.; US Patent Publication 2014/0036633 to Oberdorfer; US Patent Publication 2013/0220020 to Wigh et al.; US Patent Publication 2013/0197824 to Baba et al.; US Patent Publication 2011/0126626 to Koch et al.; and US Patent Publication 2009/0112094 to Qin et al., each of these publications being incorporated by reference herein in their entireties. 
     Example embodiment nondestructive inspection device  100  also includes a visual inspection element  120 , which may be a camera. Visual inspection element  120  may be co-located with tester  110  so as to capture visual data from a same vantage as ultrasonic data being detected by tester  110 . Similarly, visual inspection element  120  may be offset or fairly remote from tester  110  at a known relative distance, to permit adjusting visual data with respect to received ultrasonic testing data from tester  111 . Visual inspection element  120  may be configured to operate in a working fluid, such as at extreme depths of water in a nuclear reactor environment. As such, visual inspection element  120  may be a camera sealed against higher pressures and/or hardened against irradiation or radionuclide particulate entrainment. Such a camera may include appropriate lens systems and/or lighting to capture and record and/or transmit visual data for processing or operator usage, even at great fluid depths or without external lighting. 
     Example embodiment nondestructive inspection device  100  may also include an orientation determinator  130 , which may be an accelerometer, compass, infrared tag reader, level, GPS receiver, etc. that gives information as to position and/or orientation of device  100  with respect to a known reference frame. For example, an accelerometer oriented with tester  110  and beams  111  may use gravity to determine an absolute orientation of device  100 —and ultrasonic data from tester  111  and visual data from camera  120 —with respect to ground or true vertical. Rotation in other dimensions, as well as velocity or vibration, may be equally detectable with orientation determinator  130  in order to adjust, interpret, or correct data received and transmitted by device  100 , as well as properly position and move device  100  for inspections. 
     Visual inspection element  120 , tester  110 , orientation determinator  130 , and any other electronic component of device  100  may be locally or remotely powered. For example, as shown in  FIG. 2 , a power connection  160 , like a cord or cable, may provide external power to aspects of example embodiment device  100 . Alternately or in addition, local batteries may power, or provide backup power to, some or all components, like visual inspection element  120 , a processor, orientation determinator  130 , wireless communicator, tester  110 , etc. Power connection  160  may also carry ultrasonic testing, orientation, command/control, and/or visual data back to an operator or processor. Still further, a wireless connector in example device  100  may transmit data between a user and device  100 . 
     Example embodiment nondestructive inspection device  100  may be freely mobile with respect to object  50  during inspection, with or without exact position of device  100  being set or controlled. Device  100  may also include motive structures to move with respect to inspection objects  50  in a working fluid. For example, a positioning pole  150  may extend down to visual inspection device  120  and tester  110 , and an operator may manipulate or move device  100  on an opposite end of pole  150 . Similarly, a rope or other suspension system may be used with or for pole  150  to maneuver example embodiment devices  100  with appropriate rigging. Or, for example, a jet, propeller, or other fluid-motive or mechanical drive may be included in example device  100  to provide desired movement in a working fluid. An operator may remotely control device  100  through a same wireless data connection used for visual and ultrasonic data, permitting desired movement and orientation during inspection. 
     Example embodiment nondestructive inspection device  100  may further include a processor and local data store with programming and/or saved data to execute example methods discussed below. For example, a processor and appropriate memory and bus may be in a portion of element  130  in  FIG. 2 . As such, device  100  may be capable of processing and/or analyzing received ultrasonic, positional, and/or visual data as well as received control signals. A processor may further interpret received operational or control signals and translate the same into behaviors of tester  110 , visual inspection device  120 , a movement drive, determinator  130 , data transmitter, etc. 
     Example embodiments can be used in a variety of ways to perform visual and nondestructive testing of components. For example, in a nuclear power plant, like a BWR, ESBWR, PWR, CANDU, or ABWR, areas, like underwater next to a component weld or in a spent fuel pool, example embodiment devices may be introduced to visually and/or ultrasonically test components for placement, internal integrity, shape, appearance, etc., with or without regard for set positioning of example embodiment devices. Example embodiment devices may also be used in conjunction with example methods discussed below, such as through appropriate programming or operator action. However, example embodiment devices may also engage in other behaviors and activities useful in inspection environments. 
     Example Methods 
       FIG. 3  is a flowchart illustrating an example method of nondestructive testing using a testing device. As shown in  FIG. 3 , in S 300  visual, ultrasonic testing, and/or positional data are received from appropriate detector(s), like an ultrasonic testing device. For example, using an example embodiment device shown in  FIG. 4 , a user maneuvering the device about component  50  may collect data from tester  110 , camera  120 , accelerometer  130 , etc. being operated in a fluid medium in which component  50  is immersed. Alternatively, orientation data could be derived from image processing on visual data alone, or visual data could be reconstructed from received ultrasonic testing data. As such, the visual, ultrasonic, and positional data may come from several different sources and even be derived from one-another. In S 300 , data may be retrieved in real-time and simultaneously, such as ultrasonic pings being detected and associated with particular video frames and accelerometer outputs. Or, in S 300 , different types of data may be received asynchronously and stored or otherwise used at later points in time as other data is received. 
     In S 301 , a distance to a closest point and thus working plane is determined using at least some data received in S 300 . For example, using an example embodiment ultrasonic testing device of  FIG. 4 , a working plane  401  may be a plane tangent to a closest detection point  402  from a vantage. In  FIG. 4 , the vantage is tester  110  and camera  120  receiving visual and ultrasonic data at a same point, but separated and different vantages may be used in example methods with appropriate accommodation for separation between vantages. Because closest point  402  is a smallest distance away, ultrasonic signals received from emitted beams  111  may be strongest and/or fastest reflected back to a sensor and detected from closest point  402 . By identifying a strongest signal among several ultrasonic bursts  111  emitted in several directions to working plane  401 , such as among those emitted by a phased array matrix focused on working plane  401 , a distance from the vantage to object  50  can be determined with the known speed of sound in the working medium. For example, a ping  111  first received back at 0.67 milliseconds may correspond to a distance of approximately 0.5 m for “z” in water—the distance to closest point  402  and working plane  401  in  FIG. 4 . Of course, other calculations and data may be used in determining object minimum distance in S 301 , such as image analysis or mechanical measurement of distance between any vantage and an object being inspected. 
     S 301  and S 300  may be repeated to ensure that a true, closest point from a vantage and working plane is identified and determined. Through spurious movement of a vantage, too coarse or incorrect focusing of ultrasonic bursts, and/or interpositioning of unwanted or transient objects, a fastest ping received in S 300  may not actually correlate with reflection from a closest point. For example, if bursts  111  in  FIG. 4  are emitted at larger angular intervals, point  402  may not be intersected and instead point  403  may be the fastest reflection point, resulting in an incorrect identification of a closest point and measurement of distance to a working plane. Refocusing of tester  110  and/or multiple rounds and gradients of emitting bursts  111  may uncover faster pings from point  402 , which can then be identified as the closest point and used to determine distance “z” to true working plane  401 . Multiple passes of S 301  and S 300  may be conducted to ensure a closest working plane is consistently identified and measured for distance. 
     In S 302 , positional data is used to derive length and orientation of the working plane, and, by successively moving the working plane to farther points on an object, to determine relative distances of several points on the inspected object and thus its surface contours. Using the example of  FIG. 4 , angle α may be known based on specifications and operation of tester  110 . For example, if tester  110  is a phased array matrix ultrasonic emitter, each of several beams  111  may be emitted at a known angle α from a cone having a known maximum sweep from tester  110 ; or, if a simple ultrasonic emitter is used sequentially at several angles, emission angles of each beam  111  will be known with respect to tester  110  as each is emitted. Angle θ can be determined from positional data. 
     For example, using accelerometer  130  in a proper orientation, an angle between tester  110  and absolute (gravitational) vertical can be determined and thus the angle θ with the maximum sweep of tester  110 . Or, for example, positional data may include only visual and ultrasonic data that can be used to determine relative positioning and striking angles through image processing, using methods like Structure-From-Motion. Knowing the angle θ between tester  110  and vertical and the relative angle a of each beam  111  with respect to tester  110 , an absolute angle Φ of each beam  111  with respect to the vertical can be determined. For a beam from the working plane  401  along distance z, knowing Φ and distance z permits calculation of a length of plane  401  as well as any distance along any beam  111  to working plane  401  from a sweep of tester  110 . 
     S 300 -S 302  may be repeated at multiple depths or using different focuses of ultrasonic testing pulses in order to map out a surface of an object being inspected. For example, beams  111  of tester  110  may be refocused in the instance a phased array matrix is used to move working plane  401  to further point  403 , which is known to be farther away than closest point  402  based on the identification of  402  as a closest point in S 301 . An ultrasonic beam  111  may be directed at farther point  403  to confirm its distance, and orientation data from accelerometer  130  and tester  110  or other positional data can determine its distance. Through successive identification of surface points and calculation of their true distance from a vantage, a continuous surface contour, with incident angles and distances, of object  50  may be mapped out. Similarly, positional data derived from visual information using Structure-From-Motion methods coupled with calculated distances from ultrasonic data can be used to determine surface information. 
     In S 303 , ultrasonic data may be corrected if it comes from positions internal to an inspected object as determined by the contour in S 302 . That is, in S 300 -S 302 , ultrasonic data and positional data was used to determine distance and shape of an inspected object&#39;s surface, but in S 303 , ultrasonic data is additionally gathered and corrected for internal nondestructive testing purposes. When a working plane is advanced beyond a closest point of an inspected object, some ultrasonic reflections of beams focused beyond the closest point may come from inside the object. This may result in ultrasonic pulses moving from a fluid working medium through a solid component and back, or through any two materials with differing densities/speeds of sound. When moving through multiple media having varying speeds of sound, ultrasonic waves will refract in proportion to the ratio of the speeds of sound in the media. That is, the ultrasonic beams being reflected from internal points, such as when a working plane is moved or a phased matrix array is refocused to internal locations, will reorient due to differences in density between a working medium and material in an object being inspected. Correcting this change in S 303  may make use of the surface contours mapped in S 302 . The change in beam direction is known by relationship of Snell&#39;s Law as sine(θ ext )*V ext /V int =sine(θ int ), where θ ext  is the external incidence angle, V ext  is the speed of the ultrasonic burst in the exterior medium, V int  is the speed of the ultrasonic burst in the interior medium, and θ int  is the mirror internal incidence angle. 
     Using  FIG. 4  as an example of S 303 , the surface and relative distances to tester  110  from object  50  may be known from S 302 . Also knowing the absolute angle Φ and focus/depth z, one can determine the striking angle of each beam  111  on object  50 . The speeds of ultrasonic pulses in a working medium like water and object  50  may be known or directly tested during inspections. As working plane  401  is advanced beyond closest point  402 , beams  111  may be focused within, and return data with, interior of object  50 . However, angles of beams  111  may change as they refract into and reflect back through object  50 . Knowing the incidence angle, velocities, and distances between vantage and reflection/data point interior to object  50  from prior actions, the change in angles of beams  111  may be corrected in S 303  using the relationship given above. By applying this treatment to identified interior ultrasonic data, on can know the true position of any reflection point in object  50  and thus correctly associate ultrasonic testing results with position in an object. 
     In S 304 , the collected, and potentially corrected, ultrasonic data and calculated distances/surface information may be presented to a user, potentially correlated with visual data. For example, if visual data from a camera  120  in  FIG. 4  is synchronized temporally and spatially with corrected ultrasonic data from a tester  110  gathered and calculated in S 300 -S 303 , then visual data returned by camera  120  may be augmented with a point cloud or data/color overlay of distances to particular objects or even pixels. Similarly, calculated distances and surface information may be presented with such visual data, like true positioning of material edges and thicknesses. 
     Of course, all types of received data and calculated information may also be presented together in S 304 . For example, visual data may include distance and/or other positional information overlaid as data points along with a color coded overlay showing ultrasonic results, and potentially cracks or other internal disruptions, in sync with the visual data. In this way, a user may be able to instantly know how far away, and/or at what angle from a vantage, a particular visual feature is on a camera feed inspecting an object. The user may also be provided with internal information about visual features, permitting an easy correlation between potential flaws or internal boundaries and external object locations. Providing this information in example methods may not require strict positioning or location tracking of any ultrasonic testing device, because such relative and absolute positional and distance information can be derived by example methods. 
     Example embodiments and methods thus being described, it will be appreciated by one skilled in the art that example embodiments may be varied and substituted through routine experimentation while still falling within the scope of the following claims. For example, while an example embodiment may use water as a working medium in a nuclear power plant to inspect a solid metallic component, it is understood that other example embodiments are useable in air and with multiple components of intermediate densities by accounting for the differing speeds of sound in these media. All such changes fall within the scope of the following claims, and such variations are not to be regarded as departure from the scope of the following claims.