Patent Description:
Use of ultrasound beams in the field of non-destructive testing (NDT) for objects is well known and widely used. Objects such as pipes, solid rods, metal sheets, and metal billets are often inspected through the use of ultrasound beams. Ultrasound inspections are used to determine the presence of geometric features such as welds, porosity, corrosion, slag, cracks, and welding defects in the objects.

In ultrasound inspection the object is exposed to ultrasound beams from transducers placed across the length of the object. Responses to the incident ultrasound beams from different parts in the object are collected by the transducers. The amplitudes of the responses are then analyzed to locate geometric features in the object.

In practical applications, an object is passed through an array of transducers arranged in a particular order to transmit ultrasonic beams into the object with various angles of incidence. Every region of interest within the object to be inspected is passed through this configuration of transducers to generate responses to the ultrasound beams transmitted from each transducer. Hence, interrogation of each object yields a large amount of data during testing. The large amount of data thus received is utilized to generate response charts that plot the amplitudes of the responses against positions of the geometric features in the object with respect to a reference point on the object. The reference point is typically fixed by an operator of the inspection system. Thus, to accurately locate a geometric object, the operator has to manually sift through multiple response charts that display output obtained from the geometric features as a result of the ultrasound beams from different transducers in the configuration.

In typical ultrasound inspection systems designed to inspect hollow pipes, for example, <NUM> ultrasound transducers are arranged to inspect the pipe. Each transducer scans the pipe and generates geometric feature responses at fixed points along the circumference of the pipe. Response data generated for one transducer for one pipe, thus, requires several kilobytes of memory storage space. Response data from the inspection system for the entire pipe, therefore, amounts to requiring megabytes of memory space.

To handle such voluminous data generated for every inspected object by these inspection systems, installation of a data management system is required. Data management systems that handle data loads of a typical inspection setup handling hundreds of test objects everyday tend to be expensive owing to the amount of data being generated and processed. To avoid expenses related to these data management systems, ultrasound inspection systems store only a part of the data obtained from the transducers by selecting specific positions in the object to generate response charts. For example, in certain systems maximum amplitudes observed at locations between fixed distances in the object are used to generate the response chart. These data reduction techniques add errors to localization of geometric features in objects since the location of the geometric feature is now determined as a function of the fixed distance as opposed to an exact location.

Moreover, the operator spends a lot of time analyzing the data obtained from inspection systems to localize the geometric feature in the object. Errors are introduced in the localization of geometric features as a result of manual interpretation of the response charts. Further, operator costs are also multiplied and added to the cost of utilization of the current-day inspection systems.

Hence, there is a need for a method and system to analyze the limited data obtained from inspection systems and presenting the geometric feature output in a form that reduces operator efforts in localization of the geometric features.

<CIT> describes measuring pipeline wall thickness as a function of position using ultrasound propagation; a series of predictive models are used, which define predictions of the ultrasound response signals as a function of different sets of parameters. <CIT> is directed to a system and method for detecting defects in a manufactured object; the system uses an ultrasound measurement system, a signal analyzer and an expected result, wherein the signal analyzer compares the signal from the measurement signal to the expected result. <CIT> describes a computer implemented method, apparatus, and computer usable program code for testing a material; a signal is sent into the material, an actual response is received, and a simulated response is generated using a functional model. The simulated response is compared to the actual response to detect a change in the material.

Reference will be made herein to exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numerals used throughout the drawings refer to the same or like parts.

Embodiments of the invention described herein relate to a method and a system for the determination of geometric features in an object. Ultrasound beams, which are produced using a plurality of ultrasound transducers, are transmitted so as to be incident on the object being inspected. The ultrasound transducers are arranged to cover the entire geometry of the area of the object to be inspected. One or more geometric features in the object cause a change in the ultrasound beam in the object and this change in the ultrasound beam is termed a geometric feature response. Examples of changes in the ultrasound beam include, but are not limited to, reflection, scattering, refraction, and deviation in the path of the beam. These responses are received by the ultrasound transducers and are processed to obtain amplitude and time of flight information. The amplitude and time of flight information of the geometric feature responses are processed to determine the location of the one or more geometric features in the object.

To obtain the location of at least one of the one or more geometric features from the received geometric feature responses, a volumetric representation of the object is generated. The volumetric representation of the object is generated using a plurality of object parameters such as the length of the object, diameter of the object, and thickness of the object. Further, a temporal map of a predicted time of flight geometric feature responses is generated. The temporal map is generated based on a predicted ultrasound beam traversal path. The predicted ultrasound beam traversal path is generated based on a plurality of transducer parameters and the volumetric representation of the object. The transducer parameters utilized to generate the beam traversal path include, but are not limited to, angle of incidence of the transducer, size of the transducer, geometry of the transducer, and the position of the transducer with respect to the object. The received geometric responses are then compared with the temporal map to determine the location of the geometric feature on the volumetric representation. The foregoing is described in greater detail in the subsequent paragraphs with the help of accompanied drawings.

<FIG> illustrates an exemplary embodiment of an ultrasound inspection system <NUM>. The ultrasound inspection system <NUM> includes an object <NUM> being tested, a plurality of ultrasound transducers <NUM>, a processor <NUM>, a user interface <NUM>, and a memory <NUM>. The ultrasound inspection system <NUM> non-destructively tests the object <NUM> to find the presence and location of geometric features in the object. The object being tested <NUM>, according to certain embodiments, can be a hollow structure or a solid structure. In particular, examples of object <NUM> include, but are not limited to, pipes, sheets, rods, nozzles, and billets. The geometric features being inspected through the ultrasound inspection system <NUM> include, but are not limited to, anomalies in the object <NUM>, cracks, welds, defects in welds, porosity, corrosion, and slag, for example. Different configurations, based on the arrangement of the plurality of ultrasound transducers <NUM> with respect to the object <NUM>, are possible to ensure that the relevant object geometry is covered. Different types of transducer configurations include, but are not limited to longitudinal, transverse, heat affected zone (HAZ) and tandem configuration of transducers. The ultrasound transducer <NUM> configuration shown in <FIG> is decided based on the type of geometric feature to be located. The angles at which the transducers <NUM> are arranged with respect to the object <NUM> provide for different incident angles to the ultrasound beams transmitted by the transducers <NUM>. The plurality of ultrasound transducers <NUM> can be unidirectional transducers or bi-directional transducers. In one embodiment, the transducers <NUM> may represent Electromagnetic Acoustic Transducers (EMATs) used to generate ultrasound beams that are incident on the object <NUM>.

The processor <NUM>, in certain embodiments, may comprise a central processing unit (CPU) such as a microprocessor, or may comprise any suitable number of application specific integrated circuits working in cooperation to accomplish the functions of a CPU. The processor <NUM> may include a memory <NUM>. The memory <NUM> can be an electronic, a magnetic, an optical, an electromagnetic, or an infrared system, apparatus, or device. Common forms of memory <NUM> include hard disks, magnetic tape, Random Access Memory (RAM), a Programmable Read Only Memory (PROM), and EEPROM, or an optical storage device such as a re-writeable CDROM or DVD, for example. The processor <NUM> is capable of executing program instructions, related to the system for determining geometric features in the object <NUM>, and functioning in response to those instructions or other activities that may occur in the course of determining geometric features. Such program instructions will comprise a listing of executable instructions for implementing logical functions. The listing can be embodied in any computer-readable medium for use by or in connection with a computer-based system that can retrieve, process, and execute the instructions. Alternatively, some or all of the processing may be performed remotely by additional processors <NUM>.

The ultrasound transducers <NUM> may be placed on a stationary electronic arm or a movable electronic arm, for example. In one embodiment, the processor <NUM> may be configured to move such an electronic arm (not shown) holding the transducers <NUM> along the length of the object <NUM> to cover the geometry to be inspected. Alternatively, the electronic arm may be held stationary while the object <NUM> is moved across the array of ultrasound transducers <NUM>. Further still, both the electronic arm and the object <NUM> may be moved in coordination such that ultrasound beams from the transducers <NUM> can be transmitted so as to be incident on the area of the object <NUM> to be inspected. In certain embodiments, the object <NUM> may be placed on a movable rail to move and/or rotate the object <NUM>. In certain other embodiments, the ultrasound transducers <NUM> may be placed in a handheld probe assembly that may be moved along the length of the object <NUM> for inspection by an operator.

During inspection each of the ultrasound transducers <NUM> generate and transmit ultrasound beams to be incident on the object <NUM>. The ultrasound beams travel from the ultrasound transducers <NUM> into the object <NUM> and geometric feature responses, caused due to the presence of geometric features in the object <NUM>, are received by the transducers <NUM>. The ultrasound transducers <NUM>, when bidirectional, are configured to receive the responses from the geometric features in the object <NUM>. In other configurations, when transducers <NUM> are unidirectional, one transducer <NUM> transmits the ultrasound beam, and another transducer <NUM> is arranged so as to collect the responses from the geometric features in the object <NUM>. For example, in tandem configuration of transducers <NUM>, two transducers <NUM> are placed on one side of the area of interest of the object <NUM> to transmit ultrasound beams, and one transducer <NUM> is placed to receive the responses from the geometric features.

The processor <NUM> receives the geometric feature responses from the transducers <NUM> to generate a response chart that captures geometric feature response amplitudes from different parts of the object <NUM>. In one embodiment, the processor <NUM> is configured to display the response chart on a display screen. In another embodiment, the processor <NUM> is configured to display the response on the user interface <NUM>.

The response chart generated by the processor <NUM> is then analyzed by the operator to determine the presence and location of geometric features in the object <NUM>. During analysis, an amplitude threshold is defined for the geometric feature response. The operator identifies those positions corresponding with amplitudes greater than the defined threshold as being positions corresponding to the geometric features. An exemplary response chart for the ultrasound inspection system <NUM> is provided in <FIG>.

Before the object <NUM> is tested, a reference run of the inspection may be carried out by the ultrasound imaging system <NUM>. In the reference run, ultrasound beams generated from the ultrasound transducers <NUM> are transmitted to be incident on a reference object with known locations of geometric features. Amplitudes of responses received by the transducers <NUM> from the reference object are then used to determine if the responses from the known locations of geometric features are above the defined threshold. Calibration operations, such as changing the position of one or more of the ultrasound transducers <NUM>, may be carried out to ensure that the position determined from the amplitude matches the known location.

<FIG> is an exemplary geometric feature response charts <NUM> generated by the processor <NUM> of the ultrasound inspection system <NUM> from the object <NUM> and displayed on the user interface <NUM>. The response chart <NUM> in <FIG> is a <NUM>- dimensional response chart representing the responses received from the object <NUM> to the incident ultrasound beam. In certain embodiments, the geometric feature responses that are received by the transducers <NUM> are stored in the memory <NUM>. The processor <NUM> reads this data stored in the memory <NUM> to generate the response charts <NUM>. In certain embodiments, the transducers <NUM> are configured to transmit the geometric feature responses to the processor <NUM> through a communication channel between the transducers <NUM> and the processor <NUM>. The communication channel may be a wired/wireless network. In other embodiments, the geometric feature response is transmitted to the processor <NUM> through a communication channel between the inspection system <NUM> and the processor <NUM>. In certain embodiments, the processor <NUM> may be a part of a remote server system that is in communication with the ultrasound inspection system <NUM>. The ultrasound transducers <NUM> may then be coupled to at least one transmitter that is configured to transmit geometric feature responses to the processor <NUM>. In the response chart of <FIG>, amplitudes <NUM> of responses to the incident ultrasound beams from geometric features in the object <NUM> are plotted against locations <NUM> of the response in the object <NUM>. The amplitudes may represent units of frequency, while the locations <NUM> of the responses are measured with respect to a reference point on the object <NUM> and may represent units of length, for example. To determine the presence of a particular geometric feature in the object, an amplitude threshold is defined by the operator. Positions for which the amplitude values lie above the threshold correspond to locations of the geometric features. For example, if the amplitude of the response corresponding to the point <NUM> crosses the defined threshold, it may be concluded that a geometric feature is present at a point on the location axis <NUM> that corresponds to the point <NUM>. While inspection is being carried out by the ultrasound inspection system <NUM> on the object <NUM>, such response charts are generated by the processor <NUM> for each ultrasound transducer from the transducers <NUM>. The response charts may be observed by the operator either on a paper or via a display.

In certain embodiments, the geometry of the object <NUM> is divided in smaller segments, termed the 'pitch' of the object <NUM>. For example, for the object <NUM> illustrated in <FIG>, the length of the object <NUM> may be split in smaller segments <NUM>, where each segment is termed the pitch in the object <NUM>. In certain embodiments, the object <NUM> may be divided in segments <NUM> of different sizes. The object <NUM> may also have segments <NUM> of the same size. In certain embodiments, in the response chart, a maximum value from the amplitudes of responses for every pitch of the object <NUM> is plotted. Further, in certain embodiments, for each pitch of the object <NUM>, time of flight information is collected for the location corresponding to the maximum amplitude geometric feature response.

In the present technique, the time of flight information for the responses received by the transducers <NUM> from different points in the object <NUM> is used to determine the presence of geometric features in the object <NUM>. In one embodiment, each of the received geometric feature responses is compared with points in a temporal map of a predicted time of flight geometric feature response. The temporal map of the predicted time of flight geometric feature response is generated by the processor <NUM> based on a predicted beam traversal path. The processor <NUM> generates the predicted beam traversal path based on a plurality of transducer parameters and a volumetric representation of the object <NUM>. The volumetric representation of the object <NUM> is generated by the processor <NUM> based on a plurality of object parameters. The object parameters include, but are not limited to, object thickness, object diameter, object geometry and object length. Object geometry includes, but is not limited to, details pertaining to shape of the object <NUM>, angles of curvatures, cone angles, and bends observed in the object <NUM>. Based on the available geometric information of the object <NUM>, the object <NUM> is reconstructed by the processor <NUM> to generate a <NUM>-dimensional image of the object <NUM>. The <NUM>-dimensional image, in certain embodiments, is generated by the processor <NUM> by utilizing <NUM>-dimensional modeling software such as AutoCAD™ and CATIA™. In certain embodiments, a geometrically proportional physical model of the object <NUM> is utilized as the volumetric representation of the object <NUM>.

<FIG> illustrates exemplary predicted beam traversal paths <NUM> of the ultrasound beams transmitted by the transducers <NUM> in the object <NUM>. The predicted beam traversal paths <NUM> are a representation of a path that the ultrasound beams transmitted by the ultrasound transducers <NUM> take in the object <NUM>. The predicted beam traversal paths <NUM> are determined based on the volumetric representation of the object <NUM>, and a plurality of transducer parameters specific to the transducers <NUM>. The predicted beam traversal paths <NUM> are generated based on the angle of incidence of the ultrasound transducers <NUM> from which the ultrasound beams are transmitted. The angle of incidence of the transducers <NUM> is selected based on the area of interest <NUM> of the object <NUM> that needs to be inspected. The angle of incidence for the transducers <NUM> is selected such that ultrasound beam is incident on the entire desired area of interest <NUM>. Further, the location of the transmitting ultrasound transducers <NUM> along the object <NUM>, and operating frequency of the transmitting transducers <NUM> also influence the beam traversal paths <NUM> in the object <NUM>. In other embodiments, a skew angle (i.e. whether the transducers <NUM> are "in plane" or "out of plane" with respect to the object <NUM>) associated with the transducers <NUM> may also be utilized to generate the predicted beam traversal paths <NUM>. In certain embodiments, an operator of the system <NUM> provides the plurality of transducer parameters to the processor <NUM> through the user interface <NUM>. In the exemplary illustration, item <NUM> represents the points of origin of the beams <NUM> from the transducers <NUM>. The beams originate from the points <NUM> in the ultrasound transducers <NUM> and undergo redirections within the object <NUM>. The beams continue to travel in the object <NUM> and, in certain embodiments, may undergo multiple redirections in path. Item <NUM> is an exemplary point of redirection for the beams <NUM> in the object <NUM>.

The determination of the beam traversal paths <NUM> involves determination of the beam traversal path length along with the points of redirection. The path length and the points of redirection are determined based on the angle of incidence of the transmitting ultrasound transducers <NUM> and physical principles that govern beam propagation in the object <NUM>. Principles such as Ultrasound Ray Theory, Snell's Law of refraction, laws of acoustic reflection, and Fermat's principle that determine how beams travel through solid and gaseous bodies are utilized to determine the predicted beam traversal paths <NUM>.

Unfocused ultrasound beams are transmitted with a cone angle that governs a lateral spread of the beam, termed beam spread, along the beam traversal path. The ultrasound beam spread for the beam emanating from the transducers <NUM> is determined based on the size of the transducers <NUM>, geometry of the transducers <NUM>, and the angle of incidence of the transducers <NUM>. The determined beam spread for the beam emanating from the transducers <NUM> is applied across the beam traversal path length to generate the predicted beam traversal paths <NUM>.

In certain embodiments, it is assumed that the speed of sound in the object <NUM> is constant. The speed of sound can also be calculated at different locations in the object <NUM>. The speed of sound at different locations influences the predicted beam traversal paths <NUM>. In certain embodiments, the speed of sound at different locations is utilized to correct the predicted beam traversal paths <NUM>. According to certain embodiments, the speed of sound in the object <NUM> may be calculated by utilizing transducers <NUM> located at two points along the object <NUM>. One of the transducers <NUM> transmits the ultrasound beam, and another transducer <NUM> receives the transmitted ultrasound beam. Based on the known distance between the transducers <NUM>, and the time taken by the by ultrasound beam to travel from one transducer <NUM> to the other transducer <NUM>, the speed of sound is calculated.

Utilizing the predicted beam traversal paths <NUM>, the temporal map of the predicted time of flight geometric feature response for each of the incident ultrasound beams is determined. During generation of the temporal map of predicted time of flight geometric feature response for each of the beams, the respective predicted beam traversal path <NUM> is divided into smaller rays. Over each ray path, presence of geometric features is assumed. The predicted beam traversal path <NUM> is also utilized to determine a path of the response back to the transducers <NUM>. The speed of the ultrasound beam in the object <NUM> and distance covered by the ultrasound beam from the origin <NUM> of the beam on the beam traversal path <NUM> to the assumed geometric feature and the beam's return to the transducers <NUM> are utilized to calculate the time of flight for the ultrasound beam from each geometric feature in the ray path. The temporal map of the predicted time of flight geometric feature response is a list of time of flight information for each of the ultrasound beams calculated based on the assumption of the presence of geometric features along every ray in each predicted beam traversal path <NUM>.

According to certain embodiments, the reference run of inspection is utilized to calculate the speed of the ultrasound beam in the object <NUM>. In the test run, when the location of the geometric feature is known, ultrasound beams from one transducer <NUM> are transmitted so as to be incident on the geometric feature. The time of flight of the geometric feature response thus collected is used to calculate the speed of the ultrasound beam. Geometric feature responses collected for ultrasound beams transmitted by multiple transducers <NUM> may also be used to calculate the speed of ultrasound beams in the object <NUM>.

The temporal map of the predicted time of flight geometric feature response is then compared with the received geometric feature response. The received geometric feature response includes time of flight information for the locations within the object <NUM> where the amplitude of the geometric feature response is greater than the defined threshold. The location corresponding to a point from the temporal map of the predicted time of flight geometric feature response that is equivalent to the time of flight of the received geometric feature response is determined as the location of the geometric feature.

The temporal map of the predicted time of flight geometric feature response is generated based on the predicted beam traversal path <NUM> for ultrasound beams originating from more than one transducer <NUM> that are arranged at an angle with respect to the object <NUM> to be able to transmit ultrasound beams that can be incident on the area of interest of the object <NUM>. For example, in <FIG>, the two transducers <NUM> are arranged on the object <NUM> to transmit ultrasound beams into the same area of interest <NUM> of the object <NUM>. Hence, two predicted beam traversal paths <NUM> from two transducers <NUM> are determined. The location of a geometric feature in the area of interest <NUM> is determined individually based on each of the predicted beam traversal paths <NUM>. The locations determined through two different predicted beam traversal paths <NUM> are compared to determine the final location of the geometric feature.

According to certain embodiments, when multiple transducers <NUM> are arranged to transmit ultrasound beams so as to be incident on the area of interest <NUM>, the amplitude information of the geometric feature responses received by the transducers <NUM> may be utilized to determine the size of the geometric feature. For example, for a particular geometric feature response it may be determined from the predicted beam traversal path <NUM> whether the ultrasound beam was incident on the geometric feature or whether the geometric feature was present at one of the edges of the ultrasound beam. Hence, the amplitude of the geometric feature response for such an ultrasound beam may not give an accurate estimate of the size of the geometric feature. The predicted beam traversal path <NUM> for other transducers <NUM> may be utilized to determine the ultrasound beam that is incident on the particular geometric feature and the size of the geometric feature may be determined based on the amplitude information included in the geometric feature response for the other transducer <NUM>.

<FIG> illustrates an exemplary representation of the location of geometric features on a volumetric representation of an object according to one embodiment of the present invention. Item <NUM> depicts locations of one or more geometric features in the volumetric representation <NUM> of the object <NUM>. The volumetric representation <NUM> of the object <NUM> is generated based on object parameters like object size, object diameter, and object thickness. The object parameters are provided to the processor <NUM>, in certain embodiments, by the operator through the user interface <NUM> to generate the volumetric representation <NUM>. The volumetric representation <NUM> is further used, along with physical principles that govern beam propagation, to determine the predicted beam traversal path <NUM>. The predicted beam traversal path <NUM> is divided in smaller segments and defects are assumed to be located along the beam traversal path <NUM> in each of the segments. The temporal map of predicted time of flight geometric feature response to the incident ultrasound beam is determined based on the assumed defect locations. Further, the received geometric feature response is compared to the predicted geometric feature response. The received geometric feature response, according to certain embodiments, is provided to the processor <NUM> for comparison with the predicted time of flight geometric feature response through the user interface <NUM>. In other embodiments, the received geometric feature response may be read by the processor <NUM> from the memory <NUM> for comparison.

A point in the volumetric representation <NUM> of the object <NUM> may be determined to be the location of the geometric feature when the time of flight of the received geometric feature response is equivalent to the predicted time of flight geometric feature response corresponding to the point. For example, in the illustrated example, the item <NUM> depicts the points where the time of flight of the received geometric feature response is equivalent to the predicted time of flight geometric feature response. Further, a longitudinal section in the predicted beam traversal path <NUM> for which the predicted time of flight geometric feature response may be equivalent to the received geometric feature response may be determined as the location of the geometric feature. In such a case, the location of the geometric feature may be a band of points in the volumetric representation <NUM> of the object <NUM>.

Further, in certain embodiments, the locations of the geometric features are displayed with respect to coordinates of the points <NUM> on X, Y, and Z axes <NUM>. Axes <NUM> respectively run along the length, width, and height of the volumetric representation <NUM> of the object <NUM>. For example, from the volumetric representation <NUM>, the location for points <NUM> is expressed in terms of corresponding points on the X, Y, and Z axes.

In one embodiment, the point <NUM> is displayed on the volumetric representation <NUM> on the user interface <NUM>. In certain embodiments, when the operator enters the time of flight of the received geometric feature response through the user interface <NUM>, the processor <NUM> determines the point <NUM> for which the corresponding predicted time of flight geometric feature response is equivalent to the received geometric feature response entered by the operator and displays the point <NUM> on the volumetric representation <NUM> on the user interface <NUM>. The processor <NUM> compares the entered time of flight with each point from the temporal map of the predicted time of flight geometric response. Each point in the predicted time of flight geometric response is spatially located on the volumetric representation <NUM> of the object <NUM>. The point <NUM> for which the entered time of flight equals the predicted time of flight geometric feature response is determined as the location of the geometric feature. The location of the geometric feature, in certain embodiments, may be displayed on the user interface <NUM> as a function of the axes <NUM>.

<FIG> is a flow diagram illustrating a method for determining the location of geometric features in the object <NUM>. To begin, ultrasound beams generated from one of the plurality of transducers <NUM> are transmitted to be incident on the object <NUM>. At <NUM>, a response of the geometric feature to the incident ultrasound beam is received by one of the transducers <NUM>. At <NUM>, a volumetric representation <NUM> of the object <NUM> is generated based on the plurality of object parameters. The object parameters may include object size, thickness, and diameter, for example. At <NUM>, a temporal map of a predicted time of flight geometric feature response is generated. The predicted time of flight geometric feature response is generated based on the predicted ultrasound beam traversal path <NUM> in the object <NUM>. The predicted ultrasound beam traversal path <NUM>, in turn, is generated based on the volumetric representation <NUM> and a plurality of transducer parameters. Transducer parameters that influence the predicted beam traversal path <NUM> from the transducer <NUM> transmitting the ultrasound beam include, but are not limited to, angle of incidence of the transducer <NUM>, position of the transducer <NUM> with respect to the object <NUM>, geometry of the transducer <NUM>, and frequency of the transducer <NUM>. At <NUM>, a point <NUM> on the volumetric representation <NUM> is determined as the location of the geometric feature when the time of flight of the received geometric feature response is equivalent to the predicted time of flight geometric feature response corresponding to the point <NUM>.

In certain embodiments, to detect presence of the geometric features, the predicted time of flight geometric feature response is calculated by assuming presence of no single defect along the beam traversal path <NUM>. The received geometric feature response is then compared with such a predicted time of flight geometric feature response by the processor <NUM>. When the received geometric feature response is not equivalent to any point from the predicted time of flight geometric feature response, the presence of a geometric feature is detected by the processor <NUM>.

In certain embodiments, the points <NUM> may be color-coded to indicate at least one of a magnitude of the geometric feature, and accuracy of the determination of the location of the geometric feature response. The magnitude of the geometric feature, for example the size of the anomaly being detected, may be determined based on the amplitude of the geometric feature response for the ultrasound beam.

Further, after the point <NUM> is determined, the location of the point <NUM> on the object <NUM> is stored in the memory <NUM>. The information stored in the memory <NUM> is utilized to calibrate errors that may occur when determining geometric features in a new object. The processor <NUM> is configured to compare the location of the point <NUM> stored in the memory <NUM> with an actual location of the geometric feature in the object <NUM>. The comparison is utilized to calibrate an error that occurs in the determination of the geometric features in the object <NUM>.

Furthermore, the reference run of inspection carried out before the object <NUM> is being inspected may be utilized to calibrate the speed of the ultrasound beam in the object <NUM>. During the reference run, when the location of the geometric feature is known, the time of flight information is received for the known geometric feature. The predicted beam traversal path <NUM> is determined for the reference run and the location of the known geometric feature is determined utilizing the aforementioned technique. If the location of the geometric feature is observed to be different from the known location, the speed of the ultrasound beam may be adjusted such that the determined location matches the known location of the geometric feature.

In certain embodiments, the received geometric feature response and the predicted time of flight geometric response are compared to determine an orientation of the geometric feature in the object <NUM> being tested. When the received geometric feature response does not correspond to any point in the predicted time of flight geometric feature response, the processor <NUM> may determine an orientation angle of the geometric feature with respect to the object <NUM>, through the predicted beam traversal path <NUM>. Further, in certain embodiments, it may also be determined whether the geometric feature is oriented at an angle with respect to a normal axis of the object <NUM> by comparing geometric feature responses received from the geometric feature to multiple ultrasound beams transmitted by the transducer <NUM> from different positions along the object <NUM>.

Further, in certain embodiments, when the location of a geometric feature in the object <NUM> is known, the predicted time of flight geometric feature response is compared with the received geometric feature response to determine a configuration of transducers <NUM> required to cause the transmitted ultrasound beams to be incident on the geometric feature at a required angle. A point of incidence of the ultrasound beam for the ray from the predicted beam traversal path <NUM> that has a geometric feature response equivalent to the received geometric feature response is determined. The point of incidence is then used to change the configuration of transducers <NUM> in such a way that the incident ultrasound beam meets the object <NUM> at the required angle.

Various embodiments described above thus provide for a method and a system for determination of geometric features in the object. The determination of location on the volumetric representation provides for an intuitive representation of the geometric feature in the object. The volumetric display also provides an accurate location of the defect that allows operators to take faster corrective actions. Further, the system and the method reduce the complexity involved in interpreting the currently available response chart from ultrasound inspection systems. Furthermore, limited information available from transducers is utilized to determine the location of geometric features, thus reducing the amount of processing time to determine the locations. In the method, multiple transducers or multiple incident angles of ultrasound beams incident on the geometric features are also utilized to refine determination of location of the geometric features.

It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. While the dimensions and types of materials described herein are intended to define the parameters of the invention, they are by no means limiting and are exemplary embodiments. Many other embodiments will be apparent to those of ordinary skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims. In the appended claims, the terms "including" and "in which" are used as the plain-English equivalents of the respective terms "comprising" and "wherein. " Moreover, in the following claims, the terms "first," "second," etc. are used merely as labels, and are not intended to impose numerical or positional requirements on their objects.

This written description uses examples to disclose several embodiments of the invention, including the best mode, and also to enable any person of ordinary skill in the art to practice the embodiments of invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those of ordinary skill in the art.

Claim 1:
A method (<NUM>) for determining location of at least one geometric feature comprising an anomaly observed in an object (<NUM>), the method comprising:
receiving (<NUM>) at least one geometric feature response to ultrasound beams incident on the object (<NUM>), wherein the ultrasound beams are produced from a plurality of ultrasound transducers (<NUM>);
generating (<NUM>) a volumetric representation (<NUM>) of the object (<NUM>) based on a plurality of object parameters;
generating (<NUM>) a temporal map of a predicted time of flight geometric feature response to the ultrasound beams based on a predicted ultrasound beam traversal path (<NUM>) in the object (<NUM>) and originating from more than one ultrasound transducer (<NUM>) that are arranged at an angle with respect to the object (<NUM>) to be able to transmit ultrasound beams incident on an area of interest of the object (<NUM>), wherein the predicted ultrasound beam traversal path (<NUM>) is generated based on the volumetric representation (<NUM>) of the object (<NUM>), and a plurality of transducer parameters, and wherein the temporal map of the predicted time of flight geometric feature response is a list of time of flight information for each of the ultrasound beams calculated based on an assumption of a presence of geometric features along every ray in the predicted ultrasound beam traversal path (<NUM>); and
determining (<NUM>) a position (<NUM>) on the volumetric representation (<NUM>) of the object (<NUM>) as the location of the geometric feature when the received time of flight geometric feature response is equal to the predicted time of flight geometric feature response corresponding to the position.