Abstract: A system includes at least one circumferentially-polarized d15 shear ring transducer and a controller electrically coupled to the at least one circumferentially-polarized d15 shear ring transducer. The at least one circumferentially-polarized d15 shear ring transducer is configured to be disposed on a structure and to detect at least one shear horizontal-type acoustic emission from damage to the structure. The controller includes a machine-readable storage medium and a processor in signal communication with the machine-readable storage medium. The processor is configured to store acoustic emission signal data in the machine-readable storage medium when a signal amplitude detected by the at least one circumferentially-polarized d15 shear ring transducer crosses a first threshold.

Abstract: A system for the non-destructive inspection of a structure includes a probe including a hollow cylindrical waveguide having a first region and a second region. The first region has a first diameter and the second region has a second diameter. The second diameter is greater than the first diameter. The first diameter is sized and configured for insertion into a structure. The system further includes at least one of sensor element capable of generating and detecting longitudinal and/or torsional ultrasonic guided waves in the waveguide. The at least one sensor element is configured to generate a guided wave pulse in the waveguide when a time-varying current is provided to the at least one sensor element. The at least one sensor element is configured to deflect reflected guided wave energy from one or more anomalies in the structure.

Abstract: A magnetostrictive transducer assembly for generating a longitudinal elastic guided wave of a selected frequency and mode and for guiding the wave into an open end of a heat exchanger tube for testing the tube. The transducer assembly comprises a current-carrying coil of wire, a magnetostrictive material wrapped around the coil of wire, a mechanism for pressing the magnetostrictive material against an inner surface of the tube, and one or more biasing magnets placed in the vicinity of the current-carrying coil of wire and the magnetostrictive material.

Abstract: A magnetostrictive transducer assembly for generating a longitudinal elastic guided wave of a selected frequency and mode and for guiding the wave into an open end of a heat exchanger tube for testing the tube. The transducer assembly comprises a current-carrying coil of wire, a magnetostrictive material wrapped around the coil of wire, a mechanism for pressing the magnetostrictive material against an inner surface of the tube, and one or more biasing magnets placed in the vicinity of the current-carrying coil of wire and the magnetostrictive material.

Abstract: A method for ultrasonic guided wave defect detection in a structure is disclosed. The method includes driving a plurality of transducers to cause guided waves to be transmitted in the structure in a predetermined direction or focused at a predetermined focal point, receiving at least one reflected guided wave signal, and generating image data of the structure based on the at least one reflected guided wave signal. Processed image data are generated by performing at least one of baseline image subtraction or image suppression on the image data, and a location of at least one possible defect in the structure is identified based on the processed image data.

Abstract: A non-contact evaluation system for evaluating a rope. The system including a transducer and a processor. The transducer is spaced apart from the rope. The transducer configured to output an ultrasonic wave in a transverse direction towards a longitudinal location of the rope, such that at least a portion of the ultrasonic wave passes around a perimeter of the rope, receive the portion of the ultrasonic wave, convert the portion of the ultrasonic wave to a signal, and output the signal. The processor configured to receive the signal, and evaluate the rope based on the signal.

Abstract: A system for detecting ice accretion includes a probe body, at least one magnetostrictive guided wave sensor for generating and receiving shear horizontal-type guided waves supported by said probe body, and a controller. The magnetostrictive guided wave sensor includes a ferromagnetic strip, at least one sensor coil disposed adjacent to said ferromagnetic strip, and at least one biasing magnet configured to induce a biasing magnetic field in said ferromagnetic strip. The controller includes a processor in signal communication with the at least one magnetostrictive guided wave sensor. The processor configured to cause the at least one magnetostrictive guided wave sensor to generate guided waves in the body, extract at least one signal feature from a guided wave signal received by the at least one magnetostrictive guided wave sensor, and determine at least one characteristic of ice accreted on an outer surface of said probe body.

Abstract: A system includes at least one guided wave transducer configured to be disposed on a surface of a pipe and a controller electrically coupled to the at least one guided wave transducer. The controller includes a machine readable storage medium and a processor in signal communication with the machine readable storage medium. The processor is configured to actuate the at least one guided wave transducer to generate a flexural mode in the pipe.

Abstract: A system for non-destructive inspection of a structure includes a magnetostrictive pulser coil and a ferromagnetic strip. The ferromagnetic strip is coupled to the structure adjacent to the pulser coil. A scanner receiver probe is located adjacent to the ferromagnetic strip. The probe includes a probe body, a position encoder, and a magnetostrictive partial loading receiver coil. A magnet applies a biasing magnetic field to the ferromagnetic strip. A pulser system generates a time-varying current in the pulser coil to induce a time-varying magnetization in the ferromagnetic strip to generate guided wave energy in the structure. The probe detects reflected guided wave energy as the probe is moved around the circumference of the structure. A processor controls the pulser system, records guided wave reflections, and process the guided wave and probe position data to generate a one-dimensional image or a two-dimensional image of anomalies in said structure.

Abstract: An inspection system includes a magnetostrictive scanner probe, a ferromagnetic strip, at least one magnet, and a processor. The magnetostrictive scanner probe includes a probe body for supporting at least one flexible sensor coil and a position encoder. The ferromagnetic strip is configured to be coupled to a structure, and the at least one magnet is configured to apply a biasing magnetization to the ferromagnetic strip. The processor is configured to cause a time-varying current to be generated in the at least one flexible sensor coil to induce a time-varying magnetization in said ferromagnetic strip perpendicular to said biasing magnetization to generate shear horizontal-type guided wave energy into said structure, and process reflected shear horizontal-type guided wave energy received by the at least one flexible sensor coil as the probe is moved relative to said structure to generate at least one two-dimensional image of a region of said structure.

Abstract: Methods and systems (10) based on guided wave thermography for non-destructively inspecting structural flaws that may be present in a structure (15). For example, such systems and methods may provide the ability to selectively deliver sonic or ultrasonic energy to provide focusing and/or beam steering throughout the structure from a fixed transducer location (12, 14, 16). Moreover, such systems and methods may provide the ability to selectively apply sonic or ultrasonic energy having excitation characteristics (FIGS. 11 and 12) which may be uniquely tailored to enhance the thermal response (FIGS. 5 and 7) of a particular flaw geometry and/or flaw location.

Abstract: A non-contact evaluation system for evaluating a rope. The system including a transducer and a processor. The transducer is spaced apart from the rope. The transducer configured to output an ultrasonic wave in a transverse direction towards a longitudinal location of the rope, such that at least a portion of the ultrasonic wave passes around a perimeter of the rope, receive the portion of the ultrasonic wave, convert the portion of the ultrasonic wave to a signal, and output the signal. The processor configured to receive the signal, and evaluate the rope based on the signal.

Abstract: An ultrasonic guided wave system for defect detection in a plate-like structure, includes at least one first circumferentially-polarized piezoelectric d15 shear ring element configured to be coupled to a structure. The controller includes a machine readable storage medium and a processor in signal communication with the machine readable storage medium. The processor is configured to cause a pulse generator to pulse the at least first circumferentially-polarized piezoelectric d15 shear ring element such that shear horizontal-type guided wave energy is transmitted in all directions in the plate-like structure, process at least one guided wave signal to identify the presence and location of at least one possible defect in the plate-like structure, and store the guided wave signal and defect detection data in the machine readable storage medium.

Abstract: A non-contact evaluation system for evaluating a synthetic rope. The system includes a first transducer, a second transducer, and a processor. The first transducer is located at a first position and configured to convert a first electrical signal into a wave directed toward the synthetic rope under test. The wave has characteristics such that at least of a portion of the wave passes around a perimeter of the synthetic rope. The second transducer is located at a second position opposite the first position and radially aligned with the first transducer. The second transducer is also configured to receive and convert the portion of the wave into a second electrical signal. The processor is configured to determine a structural health measure of the synthetic rope based on the second electrical signal.

Abstract: A method includes calculating, using a processor, an impedance or forward and reflected power coefficients of a phased system including a plurality of actuators disposed on a structure; and activating the plurality of actuators disposed on the structure to produce shear stress via ultrasonic continuous wave activation to at least one of delaminate or weaken an adhesion strength of a contamination on the structure.

Abstract: A magnetostrictive transducer assembly for generating a longitudinal elastic guided wave of a selected frequency and mode and for guiding the wave into an open end of a heat exchanger tube for testing the tube. The transducer assembly comprises a current-carrying coil of wire, a magnetostrictive material wrapped around the coil of wire, a mechanism for pressing the magnetostrictive material against an inner surface of the tube, and one or more biasing magnets placed in the vicinity of the current-carrying coil of wire and the magnetostrictive material.

Abstract: A non-contact evaluation system for evaluating a synthetic rope. The system includes a first transducer, a second transducer, and a processor. The first transducer is located at a first position and configured to convert a first electrical signal into a wave directed toward the synthetic rope under test. The wave has characteristics such that at least of a portion of the wave passes around a perimeter of the synthetic rope. The second transducer is located at a second position opposite the first position and radially aligned with the first transducer. The second transducer is also configured to receive and convert the portion of the wave into a second electrical signal. The processor is configured to determine a structural health measure of the synthetic rope based on the second electrical signal.

Abstract: A method for ultrasonic guided wave defect detection in a structure is disclosed. The method includes driving a plurality of transducers to cause guided waves to be transmitted in the structure in a predetermined direction or focused at a predetermined focal point, receiving at least one reflected guided wave signal, and generating image data of the structure based on the at least one reflected guided wave signal. Processed image data are generated by performing at least one of baseline image subtraction or image suppression on the image data, and a location of at least one possible defect in the structure is identified based on the processed image data.

Abstract: A system for defect detection in plate like structures is disclosed. The system comprises a plurality of transducers configured to be coupled to a periphery of complex-plate structure. A controller is electrically coupled to the plurality of transducers. The controller includes a machine readable storage medium and a processor in signal communication with the machine readable storage medium. The processor is configured to generate a plurality of guided wave signals using a first set of the plurality of transducers, receive the plurality of guided wave signals at a second set of the plurality of transducers, and generate tomographic pseudo-image of structural changes of the complex-plate structure based on the plurality of guided wave signals received at the second set of the plurality of transducers.

Abstract: A non-contact signal propagation property evaluation system for ropes can be deployed for a number of different applications including, but not limited to, moving lines, e.g., crane or winch and static lines, e.g., mooring lines, stays, etc., to evaluate physical properties of the ropes and, in some cases, to help evaluate structural health of the ropes. The system includes a first transducer for generating ultrasonic waves, a second transducer for receiving ultrasonic waves propagated transversely through and around the rope, and a processor executing computer readable code to determine acoustic propagation properties of the rope.