FLEXOELECTRICITY ULTRASOUND TRANSDUCER IMAGING SYSTEM

Description

BACKGROUND

[0001] The present disclosure is related to imaging systems, and more particularly to ultrasonic imaging systems.

[0002] Known ultrasonic nondestructive testing applications utilize high-frequency sound waves for flaw detection and thickness gaging of objects and / or layers of material on the objects. These applications utilize test systems that include a plurality of ultrasonic transducers (UT transducers), where each UT transducer is generally a small probe that produces, transmits, and receives the high-frequency sound waves. These small probes may be combined to form larger phased arrays of probes that generate steered sound beams to perform the ultrasonic nondestructive testing.

[0003] Unfortunately, known UT transducers are made of piezoelectric crystals actuators. These actuators are ridge piezo crystals that require high voltages to see the changes electric polarization due to movement. Moreover, the rigidity and the size of the these known piezo crystals limit their utilization for portable UT imaging systems that can be utilized for flaw detection and thickness gagging of objects that have varying surfaces. As such, there is a need for a UT imaging sensor that addresses these issues.

[0004] US 2005 / 156362, in accordance with its abstract, states a method comprises contacting a ceramic powder with a first polymer and surfactant to form a slip mixture, mixing the slip mixture, injecting the slip mixture into a mold to form a green body, removing the mold from the green body, sintering the green body to form a sintered ceramic body, and embedding the sintered ceramic body in a second polymer to form a composite. An apparatus for forming a net shaped green body includes a mold, supplemental mold and mold assembly.

[0005] US 2005 / 156362, in accordance with its description, also states that the "sensor array is a multi-layer structure that includes a piezoelectric layer sandwiched by two conductor grids", where the first and second "conductor grids each consist of rows of parallel electrically conductive lines". That, preferably, the lines of the first grid "are oriented orthogonal with respect to the lines of' the second grid, "(that is, in x and y directions, respectively). This orientation creates a plurality of individually addressable regions or elements in the piezo film. As used herein, the term element refers to any region of a sensor array that can be addressed, either individually or as part of a larger region, using the rows of parallel electrically conductive lines (conductors). Piezoelectric polymer film sensors are further described in Piezo Film Sensors: Technical Manual, available from Measurement Specialities, Inc. Norristown, Pa., Apr. 2, 1999 REVB'. Further, the "piezo layer is a polarized fluoropolymer film, such as, polyvinylidene fluoride (PVDF) film or its copolymers. Conductor grids are silver ink electrodes printed on opposite sides of the PVDF film. Shield layer is made of urethane or other plastic. Foam substrate is made of TEFLON. An adhesive holds shield layer and foam substrate on opposite sides of the printed PVDF film". Reference numerals have been removed from the quoted portions of US2005 / 156362.

[0006] US 5744898, in accordance with its abstract, states an ultrasonic transducer assembly is disclosed having both transmit and receive circuitry integral to the transducer assembly for generating and receiving ultrasonic pulses. The ultrasonic transducer array which is integral with the transducer assembly preferably includes multi-layer transducer elements as transmit elements of the array and may include single layer transducer elements as receive elements. Also disclosed is an ultrasonic scanner utilizing the transducer assembly with integral transmit and receive circuitry to reduce the amount and complexity of interconnections between the transducer assembly and a scanner rack.

[0007] US 2010 / 239133, in accordance with its abstract, states a transducer having first and second surfaces including first electrode lines positioned along the first surface in a first direction and configured for grounding and second electrode lines positioned along the second surface in a direction orthogonal to the first direction. The second electrode lines are configured switching between receiving and transmitting in an interlaced manner.

[0008] US 2020 / 046320, in accordance with its abstract, states a modular array includes modular array includes one or more array modules. Each array module includes one or more transducer arrays, where each of the one or more transducer arrays includes a plurality of piezoelectric elements; a conducting interposer arranged and configured to provide acoustic absorbing backing for the one or more transducer arrays; and one or more Application Specific Integrated Circuits (ASICs). The conducting interposer and the one or more ASICs are in electrical contact with each other at a first direct electrical interface. Additionally, the conducting interposer and the one or more transducer arrays are in electrical contact with each other at a second direct electrical interface.

[0009] US 2008 / 015443, in accordance with its abstract, states a two-dimensional array ultrasonic probe includes a plurality of channels arranged apart from each other in a two-dimensional direction, each channel including a laminated piezoelectric element and an acoustic matching layer formed on the laminated piezoelectric element, the laminated piezoelectric element including a plurality of first and second electrodes arranged alternately within a piezoelectric body in a thickness direction of the piezoelectric body such that the side edges alone of the first electrodes and the second electrodes are exposed to the two mutually facing side surfaces of the piezoelectric body, respectively. The laminated piezoelectric element is mounted to a backing member. A signal side electrode and a ground electrode are formed to respectively extend from both side surface of the piezoelectric body to reach the backing member and are connected to the side edges of the first and second electrodes exposed to the side surface of piezoelectric body, respectively.SUMMARY

[0010] There is provided herein a flexoelectricity ultrasonic (UT) transducer imaging system comprising: a polytetrafluoroethylene (PTFE) layer having a front surface and a back surface; a plurality of flexoelectricity UT transducers attached to the back surface of the PTFE layer, wherein each flexoelectricity UT transducer of the plurality of flexoelectricity UT transducers has a front-end and a back-end, the front-end of each UT transducer is attached to the back surface of the PTFE layer, wherein the PTFE layer is configured as an audio membrane of the front-end of each UT transducer, the plurality of flexoelectricity UT transducers is arranged along the back surface of the PTFE layer as a two-dimensional array, and each UT transducer is configured to vibrate in a normal direction to the back surface of the PTFE layer; and a multiplexer in signal communication with each flexoelectricity UT transducer, wherein the plurality of flexoelectricity UT transducers is sandwiched between the multiplexer and the PTFE layer.

[0011] There is also provided herein a method for inspecting a part with a flexoelectricity UT transducer imaging system as described above, the method comprising: covering the part with the flexoelectricity UT transducer imaging system; applying a first set of voltages are applied to the plurality of flexoelectricity UT transducers with the multiplexer to produce vibrations in the plurality of flexoelectricity UT transducers; transmitting a plurality of sounds waves towards the part under inspection with the PTFE layer, wherein the plurality of sound waves are produced by a combination of the PTFE layer and vibrations of the plurality of flexoelectricity UT transducers; receiving a plurality of reflected sound waves from the part under inspection with the PTFE layer; producing a second set of voltages from the plurality of flexoelectricity UT transducers; receiving the second set of voltages from the plurality of flexoelectricity UT transducers with the multiplexer; and transmitting pixel data from each flexoelectricity UT transducer to a controller to produce a full image of the part under inspection.

[0012] Other devices, apparatuses, systems, methods, features, and advantages will be or will become apparent to one with skill in the art upon examination of the following figures and detailed description.BRIEF DESCRIPTION OF THE FIGURES

[0013] In the figures, like reference numerals designate corresponding parts throughout the different views. FIG. 1 is a system block diagram of an example flexoelectricity UT transducer imaging system. FIG. 2 is a side-view of the flexoelectricity UT transducer imaging system, shown in FIG. 1, placed on a non-linear part under inspection. FIG. 3 is a system block diagram of an example of a distribution of the plurality of flexoelectricity UT transducers along a back surface of the polytetrafluoroethylene (PTFE) layer shown in FIGs. 1 and 2. FIG. 4A is a system block diagram of an example of a UT transducer, shown in FIGs. 1-3, in the rest state. FIG. 4B is a system block diagram of the UT transducer, shown in FIGs. 1-4A, in the active low-frequency state. FIG. 4C is a system block diagram of the UT transducer, shown in FIGs. 1-4B, in the active high-frequency state. FIG. 4D is a system block diagram of the UT transducer, shown in FIGs. 1-4C, in the passive receive state. FIG. 5 is a system block diagram of an example of the flexoelectricity UT transducer imaging system, shown in FIGs. 1-2, operating in a first mode of operation. FIG. 6 is a system block diagram of the flexoelectricity UT transducer imaging system, shown in FIGs. 1-2, operating in another mode of operation. FIG. 7 is a flowchart of an example of a method performed by the flexoelectricity UT transducer imaging system shown in FIGs. 1-2. DETAILED DESCRIPTION

[0014] Disclosed is a flexoelectricity ultrasonic (UT) transducer imaging system comprising a polytetrafluoroethylene (PTFE) layer, a plurality of flexoelectricity UT transducers, and a multiplexer. The PTFE layer includes a front surface and a back surface and the plurality of flexoelectricity UT transducers is attached to the back surface of the PTFE layer. Each UT transducer of the plurality of flexoelectricity UT transducers has a front-end and a back-end and the front-end of each UT transducer is attached to the back surface of the PTFE layer, where the PTFE layer is configured as an audio membrane of the front-end of each UT transducer. The plurality of flexoelectricity UT transducers is arranged along the back surface of the PTFE layer as a two-dimensional array and each UT transducer is configured to vibrate in a normal direction to the back surface of the PTFE layer. The multiplexer in signal communication with each UT transducer, where the plurality of flexoelectricity UT transducers is sandwiched between the multiplexer and the PTFE layer.

[0015] In operation, the flexoelectricity UT transducer imaging system is placed on a part under inspection, covering the part. A first set of voltages are applied to the plurality of flexoelectricity UT transducers with the multiplexer to produce vibrations in the plurality of flexoelectricity UT transducers. The vibrations of the plurality of flexoelectricity UT transducers and the PTFE layer produce the sounds waves that are transmitted towards the part under inspection with the PTFE layer. A plurality of reflected sound waves from the part under inspection are then received with the PTFE layer which cause the flexoelectricity UT transducers to vibrate and produce a second set of voltages that are received by the multiplexer. The multiplexer then transmits pixel data corresponding to each UT transducer within the two-dimensional array to a controller to produce a full image of the part under inspection.

[0016] Turning to FIG. 1, a system block diagram of an implementation of the flexoelectricity UT transducer imaging system 100 is shown in accordance with the present disclosure. In this and other examples, the flexoelectricity UT transducer imaging system 100 is placed on the on a top of part under inspection 102 that linear component. The flexoelectricity UT transducer imaging system 100 includes a polytetrafluoroethylene (PTFE) layer 104, a plurality of flexoelectricity UT transducers 106, a multiplexer 108, and a controller 110. The PTFE layer 104 includes a front surface 112 and a back surface 114 and the plurality of flexoelectricity UT transducers 106 are attached to the back surface 114 of the PTFE layer 104. In this and other examples, each UT transducer of the plurality of flexoelectricity UT transducers 106 has a front-end and a back-end where the front-end of each UT transducer is attached to the back surface 114 of the PTFE layer 104. The PTFE layer 104 is configured as an audio membrane of the front-end of each UT transducer and the plurality of flexoelectricity UT transducers 106 is arranged along the back surface 114 of the PTFE layer 104 as a two-dimensional array. In this and other examples, each UT transducer is configured to vibrate in a normal direction to the back surface 114 of the PTFE layer 104. In this and other examples, the PTFE layer 104 may be placed on the part under inspection 102 utilizing a UT gel 116 to form a vacuum seal (or an approximate vacuum seal) between the font surface 112 of the PTFE layer 104 and the surface 118 of the part under inspection 102.

[0017] In this and other examples, the controller 110 may be any device capable of receiving pixel data from each UT transducer in the plurality of flexoelectricity UT transducers 106 and, in response, produce a full image of the part under inspection 102, where the image may be utilized for flaw detection and thickness gaging of the part under inspection 102. The controller 110 may be, for example, a field programmable gate array (FPGA) or a computing device that includes that one or more processors that include, for example, a microprocessor, a single-core processor, a multi-core processor, a microcontroller, an application-specific integrated circuit (ASIC), a logic device (e.g., a programmable logic device configured to perform processing operations), a digital signal processing (DSP) device, one or more memories for storing executable instructions (e.g., software, firmware, or other instructions), and / or any other appropriate combination of processing device and / or memory to execute instructions to perform any of the various operations described in the present disclosure. The one or more processors are adapted to interface and communicate with the memory and other devices via the one or more communication interfaces to perform method and processing steps as described herein. The one or more communication interfaces include wired or wireless communication buses. In various examples, it is appreciated by those of ordinary skill in the art that the processing operations and / or instructions may be integrated in software and / or hardware as part of the one or more processors, or code (e.g., software or configuration data), which is stored in the memory. The examples of processing operations and / or instructions disclosed in the present disclosure may be stored by a machine-readable medium in a non-transitory manner (e.g., a memory, a hard drive, a compact disk, a digital video disk, or a flash memory) to be executed by the one or more processors (e.g., a computer such as a logic or processor-based system) to perform various methods disclosed herein. In this and other examples, the machine-readable medium may be residing in memory within the computing device but it is appreciated by those of ordinary skill that the machine-readable medium may be located on other memory external to the controller.

[0018] In this and other examples, the PTFE layer 104 may be implemented as, or part of, a blanket of the flexoelectricity UT transducer imaging system 100. If the blanket is separate from the PTFE layer 104, the blanket layer may be attached to the PTFE layer 104 and include a front surface and a back surface, where the PTFE layer 104 is attached to the back surface of the blanket layer, and the front surface is configured to attach to a part under inspection 102. In this and other examples, the blanket may be a separate component to protect the structural integrity of the PTFE layer 104 or simply a flexible version of the PTFE layer 104 that extends beyond a physical footprint of the plurality of the UT transducers 106.

[0019] Moreover, the flexoelectricity UT transducer imaging system 100 may include, or be in signal communication with, a power source (not shown) to provide a set of excitation voltages to the flexoelectricity UT transducers of the plurality of flexoelectricity UT transducers 106. The power source provides voltages that, for example, may be less than 80 volts (or less than approximately 80 volts).

[0020] FIG. 2 is a side-view of the flexoelectricity UT transducer imaging system 100 placed on a non-linear part under inspection 200 in accordance with the present disclosure. In this and other examples, the controller 110 is shown as remote from the combination of the PTFE layer 104, plurality of flexoelectricity UT transducers 106, and multiplexer 108 but still in signal communication via signal path 202 that may be a wired or wireless connection.

[0021] It is appreciated by those of ordinary skill in the art that the circuits, components, modules, and / or devices of, or associated with, the flexoelectricity UT transducer imaging system 100 are described as being in signal communication with each other, where signal communication refers to any type of communication and / or connection between the circuits, components, modules, and / or devices that allows a circuit, component, module, and / or device to pass and / or receive signals and / or information from another circuit, component, module, and / or device. The communication and / or connection may be along any signal path between the circuits, components, modules, and / or devices that allows signals and / or information to pass from one circuit, component, module, and / or device to another and includes wireless or wired signal paths. The signal paths may be physical, such as, for example, conductive wires, electromagnetic wave guides, cables, attached and / or electromagnetic or mechanically coupled terminals, semi-conductive or dielectric materials or devices, or other similar physical connections or couplings. Additionally, signal paths may be non-physical such as free-space (in the case of electromagnetic propagation) or information paths through digital components where communication information is passed from one circuit, component, module, and / or device to another in varying digital formats, without passing through a direct electromagnetic connection.

[0022] In FIG. 3, a system block diagram of an example of an implementation of a distribution of the plurality of flexoelectricity UT transducers 106 along the back surface 114 of the PTFE layer 104 is shown in accordance with the present disclosure. In this and other examples, the plurality of flexoelectricity UT transducers 300, 302, 304, 306, 308, 310, 312, 314, and 316 are attached to the back surface 114 of the PTFE layer 104. The plurality of flexoelectricity UT transducers 300 correspond to pixel elements on of the flexoelectricity UT transducer imaging system 100 and may be oriented in rows and columns along the back surface 114 of the PTFE layer 104. As an example, the flexoelectricity UT transducers 300, 302, 304, and 306 may be oriented along a first row 318 and the flexoelectricity UT transducers 300, 308, 310, and 312 may be oriented along a first column 320. As stated earlier, the front-end of each flexoelectricity UT transducer is attached to the back surface 114 of the PTFE layer 104. As an example, the first front-end 322 of a first flexoelectricity UT transducer 300, second front-end 324 of a second flexoelectricity UT transducer 306, third front-end 326 of a third flexoelectricity UT transducer 312, and forth front-end 328 of a fourth flexoelectricity UT transducer 316 are all attached to the back surface 114 of the PTFE layer 104. In this and other examples, the multiplexer 108 is in signal communication with each flexoelectricity UT transducers 300, 302, 304, 306, 308, 310, 312, 314, and 316 and either applies a set of voltages signals to the flexoelectricity UT transducers 300, 302, 304, 306, 308, 310, 312, 314, and 316 or receives another set of voltages signals from the flexoelectricity UT transducers 300, 302, 304, 306, 308, 310, 312, 314, and 316 when received sound waves at the PTFE layer 104 are detected by the flexoelectricity UT transducers 300, 302, 304, 306, 308, 310, 312, 314, and 316.

[0023] As discussed earlier, the plurality of flexoelectricity UT transducers 300, 302, 304, 306, 308, 310, 312, 314, and 316 are arranged as a two-dimensional array on the back surface 114 of the PTFE layer 104, where each flexoelectricity UT transducer 300, 302, 304, 306, 308, 310, 312, 314, and 316 corresponds to a pixel of the two-dimensional array. In this and other examples, the size of the two-dimensional array may optionally vary based on the design preferences of the flexoelectricity UT transducer imaging system 100. As an example, the two-dimensional array may be as small as a 2 by 2 array and as large as a needed such as, for example, a 1,000 by 1,000 array or larger. As such, the number of flexoelectricity UT transducers may vary from four (4) to millions of elements.

[0024] Turning to FIGs. 4A-4D, a flexoelectricity UT transducer 400 of the plurality of flexoelectricity UT transducers 106 is shown. In this and other examples, the flexoelectricity UT transducer 400 is shown in resting state in FIG. 4A, an active low-frequency state in FIG. 4B, an active high-frequency state in FIG. 4C, and a passive receiving state in FIG. 4D. In this and other examples, the flexoelectricity UT transducer includes a front-end 402 and a back-end 404. The front-end 402 of the flexoelectricity UT transducer 400 is attached to the back surface 114 of the PTFE layer 104. The flexoelectricity UT transducer 400 may include and be constructed of one or more flexoelectricity crystal elements 406, 408, 410, and 412.

[0025] In this and other examples, for the purpose of illustration, only four flexoelectricity crystal elements 406, 408, 410, and 412 are shown, however, it is appreciated by those of ordinary skill in the art that any number of flexoelectricity crystal elements 406, 408, 410, and 412 may be utilized in forming flexoelectricity UT transducer 400 where the plurality of flexoelectricity crystal elements is arranged as in a stacked-up structure as shown. As such, in this and other examples the front-end 402 of the flexoelectricity UT transducer 400 corresponds to the front-end of the first flexoelectricity crystal elements 406. In this and other examples, each flexoelectricity crystal elements 406, 408, 410, and 412 is in signal communication with the multiplexer 108 via a plurality of signal paths 414, 416, 418, and 420, respectively. Moreover, in this and other examples, each of the flexoelectricity crystal elements 406, 408, 410, and 412 may be constructed of a polarized ceramic material such as, for example, Barium Titanate (BaTiO 3 ). Furthermore, in this example, the front-end 402 of the flexoelectricity UT transducer 400 has a corresponding front-end impedance that is matched to a PTFE impedance of the PTFE layer 104.

[0026] The polarized ceramic material of the flexoelectricity crystal elements 406, 408, 410, and 412 reacts to applied voltages to align themselves along the applied voltage such that when voltages are applied to the flexoelectricity crystal elements 406, 408, 410, and 412, the polarized ceramic material of the flexoelectricity crystal elements 406, 408, 410, and 412 will align and expand in both a vertical direction 422 and horizontal direction 424.

[0027] In an example of operation for transmitting, initially the flexoelectricity UT transducer 400 is in a resting where no voltage is applied to the flexoelectricity crystal elements 406, 408, 410, and 412. The flexoelectricity UT transducer 400 will have an initial height 426 and initial width 428. When a first set of voltages are applied in a low-frequency mode, the polarize material within flexoelectricity crystal elements 406, 408, 410, and 412 will align itself along the applied first set of applied voltages such that flexoelectricity UT transducer 400 will increase in height to a second height 430 and increase the width of some of the flexoelectricity crystal elements 406, 408, 410, and 412 to be greater than the initial width 428. When the applied first set of voltages are removed, the flexoelectricity crystal elements 406, 408, 410, and 412 will return to the resting state shown in FIG. 4A. By applying alternating current (AC) voltages 401, 403, 405, and 407 to the flexoelectricity crystal elements 406, 408, 410, and 412, the flexoelectricity UT transducer 400 may vertically vibrate 432 (in a normal direction, i.e., perpendicular to the back surface 114 of the PTFE layer 104) and horizontally vibrate 434. These vertical 432 and horizontal 434 vibrations will produce mechanical forces on the back surface 114 of the PTFE layer 104 producing low-frequency vibrations 436 of sound waves which are transmitted to the part under inspection 102 by the PTFE layer 104.

[0028] If the applied voltages are increased in the high-frequency mode, a second set of voltages 409, 411, 413, and 415 are applied in the high-frequency mode, the polarize material within flexoelectricity crystal elements 406, 408, 410, and 412 will further align itself along the applied second set of applied voltages such that flexoelectricity UT transducer 400 will further increase in height to a third height 438 and further increase the width of some of the flexoelectricity crystal elements 406, 408, 410, and 412 to be greater than the initial width 428. Again, when the applied second set of voltages are removed, the flexoelectricity crystal elements 406, 408, 410, and 412 will return to the resting state shown in FIG. 4A. By applying AC voltages for the second set of applied voltages to the flexoelectricity crystal elements 406, 408, 410, and 412, the flexoelectricity UT transducer 400 will vertically vibrate 440 and horizontally vibrate 442 stronger than the example in FIG. 4B. These vertical 440 and horizontal 442 vibrations will again produce mechanical forces on the back surface 114 of the PTFE layer 104 producing high-frequency vibrations 444 of sound waves which are transmitted to the part under inspection 102 by the PTFE layer 104.

[0029] In an example of operation for receiving reflected sound waves 446, the reverse process occurs. The flexoelectricity UT transducer 400 receives the received reflected sound waves 446 at the front source 112 of the PTFE layer 104. The received reflected sound waves 446 cause deflections to the PTFE layer 104 that cause the flexoelectricity UT transducer 400 to deflect since it is attached to the back surface 114 of the PTFE layer 104. The deflection of the PTFE layer 104 will cause the flexoelectricity UT transducer 400 to vibrate vertically 448 and horizontally 450 which will induce a first voltage 452 from the first flexoelectricity crystal elements 406, a second voltage 454 from the second flexoelectricity crystal elements 408, a third voltage 456 from the third flexoelectricity crystal elements 410, and a fourth voltage 458 from the fourth flexoelectricity crystal elements 412. These voltages will be received by the multiplexer 108 and passed to the controller 110.

[0030] In this and other examples, it is noted that the multiplexer 108 may be configured to drive or receive a very large number of voltages because the multiplexer 108 is in signal communication with each flexoelectricity crystal elements 406, 408, 410, and 412 of each UT transducer 400 in an M by N two-dimensional array of flexoelectricity UT transducers 300, 302, 304, 306, 308, 310, 312, 314, and 316 that may be over a million, where M is the number of flexoelectricity UT transducers 300, 302, 304, and 306 along the row 318 and N is the number of flexoelectricity UT transducers 300, 306, 310, and 312 along the column 320.

[0031] FIG. 5 is a system block diagram of an example of an implementation of the flexoelectricity UT transducer imaging system 100 operating in a first mode of operation in accordance with the present disclosure. In this and other examples, the plurality of flexoelectricity UT transducers 300, 302, 304, 306, 308, 310, 312, 314, and 316 are arranged into sub-pluralities, where the sub-pluralities are columns along the back surface 114 of the PTFE layer 104. Moreover, in this and other examples, a first sub-plurality 500 of the flexoelectricity UT transducers may include two columns 502 and 504 of flexoelectricity UT transducers. The second sub-plurality 506 of the flexoelectricity UT transducers may include all of the other flexoelectricity UT transducers not included in the first sub-plurality 500 of the flexoelectricity UT transducers. For purpose of ease of illustration only two the flexoelectricity UT transducers 502 and 504 are shown in the first sub-plurality 500, however, it is appreciated that the number of flexoelectricity UT transducers within the first sub-plurality 500 may vary based on the design.

[0032] In this and other examples, the flexoelectricity UT transducers 502 and 504 in combination with the PTFE layer 104 produce a plurality of sound waves that transmitted towards the part under inspection 102. The resulting reflected sound waves from the part under inspection 102 are received by the second sub-plurality 506 of the flexoelectricity UT transducers and not the flexoelectricity UT transducers 502 and 504 of the first sub-plurality 500 of the flexoelectricity UT transducers. In this and other examples, the individual flexoelectricity UT transducers within the second sub-plurality 506 of the flexoelectricity UT transducers produce a set of voltages that are received by the multiplexer 108.

[0033] Turning to FIG. 6, a system block diagram of the flexoelectricity UT transducer imaging system 100 is shown operating in another mode of operation in accordance with the present disclosure. In this and other examples, the plurality of flexoelectricity UT transducers 106 is arranged as a two-dimensional array of flexoelectricity UT transducers 600 where some of the flexoelectricity UT transducers (i.e., a first sub-plurality) are utilized to produce the sound waves that are transmitted to the part under inspection 102. This first sub-plurality 602 of flexoelectricity UT transducers 603 is located, for example, at the center of the two-dimensional array of flexoelectricity UT transducers 600. In this and other examples, a second sub-plurality 604 of flexoelectricity UT transducers 605 includes all of the flexoelectricity UT transducers in the two-dimensional array of flexoelectricity UT transducers 600 excluding the first sub-plurality 602 of flexoelectricity UT transducers.

[0034] Similar to the previous examples described above, in this example, the flexoelectricity UT transducers of the first sub-plurality 602 of flexoelectricity UT transducers in combination with the PTFE layer 104 produce a plurality of sound waves that transmitted towards the part under inspection 102. The resulting reflected sound waves from the part under inspection 102 are received by the second sub-plurality 604 of the flexoelectricity UT transducers and not the flexoelectricity UT transducers of the first sub-plurality 602 of the flexoelectricity UT transducers. Again, the individual flexoelectricity UT transducers within the second sub-plurality 602 of the flexoelectricity UT transducers produce a set of voltages that are received by the multiplexer 108.

[0035] It is appreciated that other combinations may also be utilized by the flexoelectricity UT transducer imaging system 100. In these examples, the controller 110 may be programmed to utilize different combinations for different measurements based on the part under inspection 102 or other factors.

[0036] In FIG. 7, a flowchart of an example of an implementation of the method 700 performed by the flexoelectricity UT transducer imaging system 100 is shown accordance with the present disclosure. The method 700 begins by covering 702 the part under inspection 102 with the flexoelectricity UT transducer imaging system 100 and applying 704 a first set of voltages 401, 403, 405, 407, 409, 411, 413, 415 to the plurality of flexoelectricity UT transducers 106 with the multiplexer 108 to produce vibrations in the plurality of flexoelectricity UT transducers 106. The method 700 then includes transmitting 706 a plurality of sound waves 436 or 444 towards the under inspection 102 with the PTFE layer 104, where the plurality of sound waves 436 or 444 are produced by a combination of the PTFE layer 104 and the vibrations of the plurality of flexoelectricity UT transducers 106. The method 700 then includes receiving 708 a plurality of reflected sound waves 446 from the part under inspection 102 with the PTFE layer 104 and producing 710 a second set of voltages from the plurality of flexoelectricity UT transducers 106 that are received 712 by the multiplexer 108. The method 700 then includes transmitting 714 the pixel data from each flexoelectricity UT transducer 300, 302, 304, 306, 308, 310, 312, 316, or 400 to the controller 110 to produce a full image of the part under inspection 102 and producing 716 the full image with the controller 110. The method then ends.

[0037] In this and other examples, the step of producing 710 a second set of voltages from the plurality of flexoelectricity UT transducers 106 includes producing a sub-set of voltages 452, 454, 456, and 458 from each flexoelectricity crystal element 406, 408, 410, and 412 of each flexoelectricity UT transducer 300, 302, 304, 306, 308, 310, 312, 316, or 400. Moreover, the step of receiving 712 the second set of voltages from the plurality of flexoelectricity UT transducers 106 with the multiplexer 108 includes receiving the sub-set of voltages 452, 454, 456, and 458 from each flexoelectricity crystal element 406, 408, 410, and 412 of each flexoelectricity UT transducer 300, 302, 304, 306, 308, 310, 312, 316, or 400.

[0038] In the method 700, the transmitting step 706 may also include producing the plurality of sound waves 436 or 444 from a combination of the PTFE layer 104 and the vibration of a first sub-plurality 500 or 602 of the flexoelectricity UT transducers 106, receiving the plurality of reflected sound waves 446 from the part under inspection 102 with the PTFE layer 104 and a second sub-plurality 506 or 602 of flexoelectricity UT transducers 106, and producing the second set of voltages from the second sub-plurality 506 or 602 of flexoelectricity UT transducers 106. In this and other examples, the first sub-plurality 500 or 602 of the flexoelectricity UT transducers 106 has a pattern within the two-dimensional array 600. In this and other examples, the first set of voltages 401, 403, 405, 407, 409, 411, 413, 415 may be less than 80 volts (or less than approximately 80 volts).

[0039] It should be noted and understood that improvements and modifications of the embodiments described above may be made, within the scope of protection which is defined by the appended claims.

[0040] To the extent that terms "includes," "including," "has," "contains," and variants thereof are used herein, such terms are intended to be inclusive in a manner similar to the term "comprises" as an open transition word without precluding any additional or other elements. Moreover, conditional language such as, among others, "can," "could," "might" or "may," unless specifically stated otherwise, are understood within the context to present that certain examples include, while other examples do not include, certain features, elements and / or steps. Thus, such conditional language is not generally intended to imply that certain features, elements and / or steps are in any way required for one or more examples or that one or more examples necessarily include logic for deciding, with or without user input or prompting, whether certain features, elements and / or steps are included or are to be performed in any particular example. Conjunctive language such as the phrase "at least one of X, Y or Z," unless specifically stated otherwise, is to be understood to present that an item, term, etc. may be either X, Y, or Z, or a combination thereof.

[0041] In some alternative examples, the function or functions noted in the blocks may occur out of the order noted in the figures. For example, in some cases, two blocks shown in succession may be executed substantially concurrently, or the blocks may sometimes be performed in the reverse order, depending upon the functionality involved. Also, other blocks may be added in addition to the illustrated blocks in a flowchart or block diagram. Moreover, the operations of the example processes are illustrated in individual blocks and summarized with reference to those blocks. The processes are illustrated as logical flows of blocks, each block of which can represent one or more operations that can be implemented in hardware, software, or a combination thereof. In the context of software, the operations represent computer-executable instructions stored on one or more computer-readable medium that, when executed by one or more processing units, enable the one or more processing units to perform the recited operations. Generally, computer-executable instructions include routines, programs, objects, modules, components, data structures, and the like that perform particular functions or implement particular abstract data types. The order in which the operations are described is not intended to be construed as a limitation, and any number of the described operations can be executed in any order, combined in any order, subdivided into multiple sub-operations, and / or executed in parallel to implement the described processes. The described processes can be performed by resources associated with one or more device(s) such as one or more internal or external CPUs or GPUs, and / or one or more pieces of hardware logic such as FPGAs, DSPs, or other types of accelerators.

[0042] All of the methods and processes described above may be embodied in, and fully automated via, software code modules executed by one or more general purpose computers or processors. The code modules may be stored in any type of computer-readable storage medium or other computer storage device. Some or all of the methods may alternatively be embodied in specialized computer hardware.

Claims

1. A flexoelectricity ultrasonic, UT, transducer imaging system (100) comprising: a polytetrafluoroethylene, PTFE, layer (104) having a front surface (112) and a back surface (114); a plurality of flexoelectricity UT transducers (106) attached to the back surface (114) of the PTFE layer (104), wherein each flexoelectricity UT transducer (300, 302, 304, 306, 308, 310, 312, 316, 400) of the plurality of flexoelectricity UT transducers (106) has a front-end (322, 324, 326, 328, 402) and a back-end (404), the front-end (322, 324, 326, 328, 402) of each flexoelectricity UT transducer (300, 302, 304, 306, 308, 310, 312, 316, 400) is attached to the back surface (114) of the PTFE layer (104), wherein the PTFE layer (104) is configured as an audio membrane of the front-end (322, 324, 326, 328, 402) of each flexoelectricity UT transducer (300, 302, 304, 306, 308, 310, 312, 316, 400), the plurality of flexoelectricity UT transducers (106) is arranged along the back surface (114) of the PTFE layer (104) as a two-dimensional array, and each flexoelectricity UT transducer (300, 302, 304, 306, 308, 310, 312, 316, 400) is configured to vibrate in a normal direction to the back surface (114) of the PTFE layer (104); and a multiplexer (108) in signal communication with each flexoelectricity UT transducer (300, 302, 304, 306, 308, 310, 312, 316, 400), wherein the plurality of flexoelectricity UT transducers (106) is sandwiched between the multiplexer (108) and the PTFE layer (104).

2. The flexoelectricity UT transducer imaging system (100) of claim 1, wherein each flexoelectricity UT transducer (300, 302, 304, 306, 308, 310, 312, 316, 400) of the plurality of flexoelectricity UT transducers (106) is constructed of a flexoelectricity crystal element (406, 408, 410, 412).

3. The flexoelectricity UT transducer imaging system (100) of claim 2, wherein the flexoelectricity crystal element (406, 408, 410, 412) is a Barium Titanate BaTiO3, crystal element.

4. The flexoelectricity UT transducer imaging system (100) of claim 2 or 3, wherein each flexoelectricity UT transducer (300, 302, 304, 306, 308, 310, 312, 316, 400) comprises a plurality of flexoelectricity crystal elements (406, 408, 410, 412) arranged in a stacked-up structure.

5. The flexoelectricity UT transducer imaging system (100) of any one of claim 1-4, wherein the multiplexer (108) is in signal communication with each flexoelectricity UT transducer (300, 302, 304, 306, 308, 310, 312, 316, 400) of the plurality of flexoelectricity UT transducers (106).

6. The flexoelectricity UT transducer imaging system (100) of claim 5 when dependent upon claim 4, wherein the multiplexer (108) is in signal communication with each flexoelectricity crystal element (406, 408, 410, 412) of the plurality of flexoelectricity crystal elements (406, 408, 410, 412).

7. The flexoelectricity UT transducer imaging system (100) of any one of claims 1-6, wherein the front-end (322, 324, 326, 328, 402) of each flexoelectricity UT transducer (300, 302, 304, 306, 308, 310, 312, 316, 400) has a corresponding front-end impedance, the PTFE layer (104) has a PTFE impedance, and the corresponding front-end impedance for each flexoelectricity UT transducer and the PTFE impedance are matched.

8. The flexoelectricity UT transducer imaging system (100) of any one of claims 1-7, further comprising a blanket layer attached to the PTFE layer (104), wherein the blanket layer includes a front surface and a back surface, the PTFE layer (104) is attached to the back surface of the blanket layer, and the front surface of the blanket layer is configured to attach to a part under inspection (102).

9. The flexoelectricity UT transducer imaging system (100) of any one of claims 1-8, further comprising a controller (110) in signal communication with the multiplexer (108) and, optionally, wherein each flexoelectricity UT transducer (300, 302, 304, 306, 308, 310, 312, 316, 400) of the plurality of flexoelectricity UT transducers (106) corresponds to a pixel of the two-dimensional array and the controller (110) is configured to receive pixel data from each flexoelectricity UT transducer (300, 302, 304, 306, 308, 310, 312, 316, 400) and, in response, produce a full image of a part under inspection (102).

10. A method (700) for inspecting a part (102) with the flexoelectricity UT transducer imaging system (100) of any one of claims 1-9, the method (700) comprising: covering (702) the part (102) with the flexoelectricity UT transducer imaging system (100); applying (704) a first set of voltages (401, 403, 405, 407, 409, 411, 413, 415) to the plurality of flexoelectricity UT transducers (106) with the multiplexer (108) to produce vibrations in the plurality of flexoelectricity UT transducers (106); transmitting (706) a plurality of sound waves (436, 444) towards the part (102) with the PTFE layer (104), wherein the plurality of sound waves (436, 444) are produced by a combination of the PTFE layer (104) and the vibrations of the plurality of flexoelectricity UT transducers (106); receiving (708) a plurality of reflected sound waves (446) from the part (102) with the PTFE layer (104); producing (710) a second set of voltages from the plurality of flexoelectricity UT transducers (106); receiving (712) the second set of voltages from the plurality of flexoelectricity UT transducers (106) with the multiplexer (108); and transmitting (714) pixel data from each flexoelectricity UT transducer (300, 302, 304, 306, 308, 310, 312, 316, 400) to a controller (110) to produce a full image of the part (102).

11. The method (700) of claim 10, wherein each flexoelectricity UT transducer (300, 302, 304, 306, 308, 310, 312, 316, 400) is a constructed of a flexoelectricity crystal element (406, 408, 410, 412) and comprises a plurality of flexoelectricity crystal elements (406, 408, 410, 412) arranged in a stacked-up structure, and wherein producing a second set of voltages from the plurality of flexoelectricity UT transducers (106) includes producing a sub-set of voltages (452, 454, 456, 458) from each flexoelectricity crystal element (406, 408, 410, 412) of each flexoelectricity UT transducer (300, 302, 304, 306, 308, 310, 312, 316, 400).

12. The method (700) of claim 11, wherein the multiplexer (108) is in signal communication with each flexoelectricity UT transducer (300, 302, 304, 306, 308, 310, 312, 316, 400) of the plurality of flexoelectricity UT transducers (106), and wherein receiving the second set of voltages from the plurality of flexoelectricity UT transducers (106) with the multiplexer (108) includes receiving the sub-set of voltages (452, 454, 456, 458) from each flexoelectricity crystal element (406, 408, 410, 412) of each flexoelectricity UT transducer (300, 302, 304, 306, 308, 310, 312, 316, 400).

13. The method (700) of any one of claims 10-12, wherein transmitting a plurality of sound waves (436, 444) towards the part (102) with the PTFE layer (104) includes producing the plurality of sound waves (436, 444) from a combination of the PTFE layer (104) and the vibration of a first sub-plurality (500) of the flexoelectricity UT transducers (106), receiving the plurality of reflected sound waves (446) from the part (102) with the PTFE layer (104), and producing the second set of voltages from a second sub-plurality of flexoelectricity UT transducers (106).

14. The method (700) of any one of claims 10-13, further including receiving with the controller (110) pixel data from each flexoelectricity UT transducer (300, 302, 304, 306, 308, 310, 312, 316, 400) and, in response, produce a full image of the part under inspection (102).

15. The method (700) of any one of claims 10-14, wherein the first set of voltages (401, 403, 405, 407, 409, 411, 413, 415) are less than 80 volts or less than approximately 80 volts.