Abstract: A system comprises an engine mounted to an aircraft wing by a plurality of clevis pins, a respective strain sensor mounted in at least one of the clevis pins, and a monitoring system operatively connected to each respective strain sensor to monitor stress in each of the clevis pins having a respective strain sensor.

Abstract: A joint evaluation method of evaluating a joint state of a joint portion in a composite including the joint portion in which a first adherend and a second adherend are joined to each other through an adhesive is provided. The joint evaluation method includes applying an alternating-current signal to the joint portion; changing frequency to measure current and voltage; calculating an evaluation value related to a given electrical characteristic from a current value and a voltage value obtained by the measurement; comparing the evaluation value with a preset criterion related to the given electrical characteristic; and evaluating the joint state of the joint portion according to an amount of deviation of the evaluation value from the preset criterion.

Abstract: A method for auto-calibrating a non-destructive testing instrument. In accordance with some embodiments, the method comprises: (a) determining a first set of coordinates in a test object coordinate system of the test object, the first coordinates representing a target position on a surface of the test object; (b) storing a calibration file in a memory of the non-destructive testing instrument, the calibration file containing calibration data which is a function of structural data representing a three-dimensional structure of the test object in an area containing the target position; (c) calibrating the non-destructive testing instrument using the calibration data in the calibration file; and (d) interrogating the target position using the calibrated non-destructive testing instrument.

Abstract: A device for evaluating quality of welding spots of a panel is disclosed. The device includes a vibration transferring member, a first access member contacted with one surface of one end portion of the vibration transferring member and with the one surface of the panel, a second access member contacted with one surface of the other end portion of the vibration transferring member and with the one surface of the panel, an oscillator for supplying vibration to the one end portion of the vibration transferring member, a sensor disposed on the vibration transferring member to detect characteristic of vibration transferred along the vibration transferring member, and a computing device for analyzing characteristic of the welding spots using characteristic of vibration detected in the sensor.

Abstract: Electromagnetic and eddy current techniques for fast automated real-time and near real-time inspection and monitoring systems for high production rate joining processes. An eddy current system, array and method for the fast examination of welds to detect anomalies such as missed seam (MS) and lack of penetration (LOP) the system, array and methods capable of detecting and sizing surface and slightly subsurface flaws at various orientations in connection with at least the first and second weld pass.

Abstract: In accordance with the present disclosure, a method of using acoustic emission data to predict the state of a structural element is described. The method includes capturing acoustic emission data for a structural element. The method further includes predicting the future stress intensity in the structural element using the captured acoustic emission data and calculating the probability of future failure of the structural element using the predicted future stress intensity.

Abstract: A patch and associated methods for monitoring and inspecting a structure are provided in order to facilitate such inspections. The patch includes a sheet of material configured to be attached to the structure and a frequency steerable array carried by the sheet of material. The frequency steerable array includes a plurality of sources for emitting structural waves in response to an input having a variable frequency such that variations in the frequency of the input cause the structural waves emitted by the plurality of sources to be controllably steered relative to the sheet of material. Methods utilizing one or more frequency steerable arrays for monitoring and inspecting a patch-repaired structure are also provided.

Abstract: An ultrasound-based measuring device includes a measurement body, at least one ultrasonic transmitter for coupling ultrasonic measurement signals into the measurement body, and at least one ultrasonic receiver for detecting the ultrasonic measurement signals reflected at an end face of the measurement body. The at least one ultrasonic transmitter emits both a longitudinal and a transverse measurement signal. The influence of a physical disturbance variable on the measurement section traversed by the measurement signals during a determination of a measurement pressure prevailing at the end face and/or of a measurement temperature prevailing at the end face can be taken into account on the basis of the propagation times and a difference between the propagation times of the longitudinal and transverse measurement signals reflected at the end face.

Abstract: The invention relates to a method of estimating the internal state of a first electrochemical system for electric power storage, such as a battery, wherein at least one property relative to the internal state of the first electrochemical system is estimated from acoustic emission measurements.

Abstract: Methods are disclosed relating to the assessment of fatigue damage in objects that include for example, subjecting a fatigued object to a cyclic mechanical stress, measuring a rate of temperature rise in the fatigued object, and assessing a degree of fatigue of the fatigued object based on the rate of temperature rise in the fatigued object. Methods of measuring internal structural characteristics and methods of correlating fatigue damage to results from excitation tests are also taught.

Abstract: A detection and alarm system comprises a piezoelectric film sensor and associated circuitry. The sensor detects acoustic emission signals from metallic objects under stress upon which it is affixed. The associated circuitry receives electronic signals from the sensor, creates and evaluates a sensor output value including rate ratio and frequency content of such signals within preset time limits. This data allows the detection of impending failure, an alarm condition, of the metallic object by identifying significant changes in the rate of emission of such sensor signals. An alarm condition may then trigger an alarm signal to warn of such impending failure.

Abstract: A method, apparatus and software is disclosed for using parameters of acoustic emissions emitted from an structure, such as aircraft landing gear, for detecting yield in the structure.

Abstract: A system for evaluating integrity of a cutting blade includes at least one stress wave generator for generating at least one stress wave in a cutting blade under test. A sensor detects a signal generated by the at least one stress wave. An integrity analyzer coupled to the sensor determines an indication of integrity of the cutting blade based on at least one characteristic of the signal.

Abstract: In a method and a device for determining a leak in at least one system component (2.1 through 2.n) and/or a state of a system component (2.1 through 2.n) of a system, at least one section of one or more system components (2.1 through 2.n) is monitored optically. Sound emissions occurring in or on at least one of the system components (2.1 through 2.n) are detected, analyzed and localized, wherein acoustically localized sound emission areas of the affected system component (2.1 through 2.n) are also optically detected and analyzed.

Abstract: A strain measurement device to assess the integrity of a structural repair to a surface comprises a detector, a processor, and a memory module coupled to the processor. The memory module comprises logic instructions stored in a computer readable medium which, when executed by the processor, configure the processor to use the detector to obtain a first strain measurement from an external strain indicator, use the detector to obtain a second strain measurement from the measurement sensor after at least one stress test is applied to the structural repair, and generate a signal when a difference between the first strain measurement and the second strain measurement exceeds a threshold.

Abstract: A system for detection of stress and deformation in a structural asset, for instance, one of reinforced concrete. An area on the asset may have a structure interface, such as a patch, attached to it with a fastening mechanism which may be a layer of an epoxy or other material, or be items such as screws, bolts, welds, or the like. One or more surface acoustic wave (SAW) strain sensors may be attached to the interface with an adhesive layer of epoxy or other material, or with mechanical items. Stress may be transmitted by the interface to the strain sensors. The sensors may be interrogated with a wire or wireless reader to obtain strain measurements. The measurements may indicate stress and deformations such as bulges and breaks in the asset. The measurements may also be a basis for determining location and extent of the stress and deformations.

Abstract: Inspecting for fracture hazards by detecting a presence of at least one flaw development process in an equipment under inspection, the flaw development process being corrosion product nucleation and development, pitting, plastic deformation development, and/or micro-cracking. Detecting the presence of the flaw development process includes (a) determining at least one characteristic acoustic emission (AE) signature associated with a respective flaw development process, and (b) measuring an AE from each of a plurality of locations within the equipment. Presence of the respective flaw development process is identified only when the measured AE conforms to the characteristic AE signature within a predetermined tolerance. A fracture hazard is determined to exist only when (a) a quantity of the identified flaw development processes exceeds a first predetermined threshold and/or (b) a magnitude of at least one of the identified flaw development processes exceeds a second predetermined threshold.

Abstract: A system for detection of stress and deformation in a structural asset, for instance, one of reinforced concrete. An area on the asset may have a structure interface, such as a patch, attached to it with a fastening mechanism which may be a layer of an epoxy or other material, or be items such as screws, bolts, welds, or the like. One or more surface acoustic wave (SAW) strain sensors may be attached to the interface with an adhesive layer of epoxy or other material, or with mechanical items. Stress may be transmitted by the interface to the strain sensors. The sensors may be interrogated with a wire or wireless reader to obtain strain measurements. The measurements may indicate stress and deformations such as bulges and breaks in the asset. The measurements may also be a basis for determining location and extent of the stress and deformations.

Abstract: A diagnostic means to enable real-time inspection of bonded structures. The disclosed apparatus detects bond failure stress waves on-axis from the front side (beam application side). Pi-box and pi-rail EMAT gauges can be used with the disclosed apparatus. An inductively coupled EMAT may also be employed. An improved means to remotely deliver an interrogating laser beam to a surface is provided. The process head may utilize a water column or a water film. The water film process head may include the use of either a single water film or two spaced apart water films. The disclosed apparatus can be used with bonded composite structures, bonded structures using various materials, and to determine the dynamic strength of unbonded solid materials. The apparatus may also be used in other applications that require remote flexible delivery of a localized stress wave to a material and/or diagnosis of the resultant stress waves.

Abstract: Methods, systems, and apparatuses are provided for creating bond delaminations in a controlled fashion within adhesively bonded structures. In one embodiment, a system for inducing a defect in a bond of a bonded article includes a laser and a laser processor head. The laser processor head includes a housing, a lens disposed within the housing, at least one magnet disposed within the housing, and at least one sensor disposed within the housing. The system is capable of applying a laser pulse of sufficient energy fluence to cause localized weaknesses in the bond.

Abstract: This invention relates to a device for mounting in a fixed mounted frame (7) on a subsea pipe comprising a locking device comprising a sensor housing (6), a spring (2) surrounding the sensor housing (6), at least one wedge (1) placed in one of the ends of the spring (2), and a edge (5a) placed in the other end of the spring (2), where the sensor housing (6) is arranged to be guided into the mounting frame (7), and that a force (13) is applied in the longitudinal axis of the sensor housing (6) so that the spring (2) is compressed and the wedge(s) (1) are spanned radial out towards the mounting frame (7) to center and support the sensor housing (6) in the mounting frame (6), the sensor housing (6) is designed to fit into the mounting frame (7).

Abstract: A contactless SAW based torque and temperature sensor comprising a first (2) and second (3) SAW resonator provided on a substrate made of Y+34° cut of quartz. The first SAW resonator (2) has its principle axis inclined at +45° to the X-axis of the substrate, which, in use is either aligned with the longitudinal axis of the device who torque is to be measured or is perpendicular thereto, and the second SAW (3) has its principle axis inclined at ?45° to the X-axis of the substrate. A third SAW (4) has its principle axis inclined at an angle of 30 degrees to the X-axis of the substrate. Each said SAW resonator (2,3,4) is formed by laying a film of aluminum on the substrate having a thickness (h) and the SAW resonators have an average operating wavelength ? where the ratio h/? is in the range 0.021 to 0.032.

Abstract: A method for testing ball bearings includes applying a Hertzian contact stress on a ball bearing to provide a fracture of the ball bearing that releases acoustic energy, establishing a signal representing the acoustic energy, and identifying occurrence of the fracture based upon the signal.

Abstract: A system for evaluating the integrity of a bonded joint in an article includes a laser configured in a laser shock processing arrangement to perform a laser shock processing treatment on the article. A beam delivery system employs an articulated arm assembly to communicate the radiant energy emitted by the laser to a process head proximate the article. The laser shock processing treatment causes the formation of shockwaves that propagate through the article, inducing internal stress wave activity that characteristically interacts with the bonded joint. A sensor detects a stress wave signature emanating from the article, which is indicative of the integrity of the bond. A detector such as a non-contact electromagnetic acoustic transducer provides a measure of the stress wave signature in the form of surface motion measurements.

Abstract: The strength of adhesion between two layers is evaluated by applying a series of laser shocks directly to the surface of one of the layers. Adhesion strength is determined based on the wavelength and energy of the laser pulse creating the shock which causes rupture of the interface between the two layers.

Abstract: The invention relates to a method for evaluating pressure containers made of a composite material by acoustic emission testing. The method comprises the steps: (a) determining a sufficient number of internal pressure-dependent acoustic emission characteristics (AE characteristics) of pressure containers from identical production that have been classified as being without defects in predetermined phases of a time-controlled pressure acting upon the pressure container (AE test procedure) with one or more acoustic emission channels (AE channels) using acoustic emission sensors (AE sensors) of a predetermined position (one AE characteristic per AE sensor or AE channel.

Abstract: This invention relates to a device for mounting in a fixed mounted frame (7) on a subsea pipe comprising a locking device comprising a sensor housing (6), a spring (2) surrounding the sensor housing (6), at least one wedge (1) placed in one of the ends of the spring (2), and a edge (5a) placed in the other end of the spring (2), where the sensor housing (6) is arranged to be guided into the mounting frame (7), and that a force (13) is applied in the longitudinal axis of the sensor housing (6) so that the spring (2) is compressed and the wedge(s) (1) are spanned radial out towards the mounting frame (7) to centre and support the sensor housing (6) in the mounting frame (6), the sensor housing (6) is designed to fit into the mounting frame (7).

Abstract: An acoustic transducer system for use in the measurement of longitudinal sound velocity in a cement sample that is maintained at high temperature and pressure. The acoustic assembly is separate from the end plugs to optimize acoustic coupling between the individual elements of the assembly, to increase the amplitude and consistency of the acoustic signal and to provide an ability to replace the transducers as a separate assembly. The transducer includes an acoustic transmission line and utilizes a pressure isolation method to optimize the material and the manufacturing process to enhance the acoustic signal required for the measurement. The transducer assembly includes a high temperature piezoelectric ceramic and a load mass that improve the signal amplitude and provide the required electrical connections. The transducer improves the ability to measure the longitudinal wave velocity in a cement sample at elevated temperature and pressure for determining the sample's compressive strength.

Abstract: A sensor includes a clevis insert for reception within a first bore of a clevis. The clevis insert is configured to accommodate a latch pin. A strain sensing element is operatively associated with the clevis insert for detecting mechanical strain imparted to the clevis insert when a force acts on the clevis insert through the pin. The invention also provides a method of retrofitting a cowl latch assembly.

Abstract: Embodiments of the present invention beneficially provide an ultrasound communication system and methods of ultrasound communication for diagnostics and prognostics of structures. For example, ultrasound transmitters are connected to a metal or composite structure and modulated to produce Lamb waves that travel to an ultrasound receiver. The ultrasound transmitters can use frequency-hopped signals to digitally encode transducer information among different transmitters. The transmitters can be operated asynchronously. The receiver can use a channel equalizer to reduce the effects of signal multipath and a decoder to decode the transducer information from the ultrasound transmitters.

Abstract: A method for measuring the rigidity of paper or other products made from cellulose fibers wherein the paper is torn and a digitized sound recording is made during the tearing process which is then analyzed to determine the percentage of time during which characteristic frequencies are present during the tearing process. It has been found that this percentage correlates well with rigidity.

Abstract: A method and apparatus for measuring the force applied by a first member coupled to a second member by a connecting body, by: transmitting a cyclically-repeating energy wave through the connecting body from a first location thereon to a second location thereon; measuring the transit time of the cyclically-repeating energy wave from the first location to the second location; and utilizing the measured transit time to produce a measurement of the force. In the preferred described embodiment, the connecting body is a fastening plate which fastens a drive shaft to a driven shaft and measures the torque output of the drive shaft.

Abstract: In a method and system for evaluating sub-critical fatigue crack growth in a semiconductor device, a plurality of energy pulses generated by an energy source are repeatedly impinged onto the semiconductor device for a predefined time interval. The repeated impinging of the plurality of energy pulses induces a mechanical stress within the semiconductor device. The induced mechanical stress, maintained below a threshold and repeated for a predefined number of cycles, causes a formation of a sub-critical fatigue crack within the semiconductor device. A detector detects the presence of the sub-critical fatigue crack leading to a fatigue failure. A rapid determination of a pass or fail status for a fatigue test of the semiconductor device is made by comparing a total number of cycles to fatigue failure to a predefined benchmark.

Abstract: A stress wave sensor comprising a piezoelectric film and means therein for connection to sensor electronics. The piezoelectric film preferably comprises polyvinylidene fluoride. Also a stress wave sensor system and methods employing one or more such stress wave sensors, preferably attached to a vehicle transparent component, most preferably to the vehicle windshield.

Abstract: A sensor network is attached to a structure and employed to detect and analyze load changes. The sensor network has transducers, capable of acting as both passive sensors and active actuators, integrated within it. In a passive mode, the transducers detect load changes upon the structure, such as impacts. Upon detection of a load change, the transducers are engaged in an active mode to actively scan the impact area to determine the location and size of any resulting damage region. In this manner, passive and active systems are integrated within a single, convenient layer that possesses the best features of both active systems and passive systems.

Abstract: A circuit breaker detects a loose electrical connection condition of a power circuit. The circuit breaker includes first and second lugs, first and second acoustic couplers acoustically coupled to the power circuit, separable contacts electrically connected in series between the first and second lugs, and an operating mechanism adapted to open and close the contacts. An acoustic generator is coupled to the second acoustic coupler and generates a first acoustic signal to the power circuit from the second acoustic coupler. An acoustic sensor is coupled to the first acoustic coupler and has a second acoustic signal which is operatively associated with the loose electrical connection condition. The acoustic sensor outputs a sensed acoustic signal. A circuit cooperates with the acoustic generator to generate the first acoustic signal, input the sensed acoustic signal, and detect the loose electrical connection condition therefrom.

Abstract: A system and method for identifying defects in a repair patch applied to a structure are provided. The system includes a sheet of material configured to be attached to the structure, and a mechanism operable to generate stress waves within and along the sheet of material. The system also includes a plurality of non-destructive sensors carried by the sheet of material. Each sensor is capable of detecting the stress waves. The system further includes a data acquisition system capable of communicating with the sensors such that the data acquisition system is also capable of generating information indicative of at least a portion of the sheet of material based on the data detected by the sensors.

Abstract: Acoustic sensing utilizing a bridge structure coupled about a portion of at least two sides of said bridge to a base substrate, wherein said bridge includes a piezoelectric section and has at least one active acoustic region proximate said bridge. A sensing material is disposed on at least a portion of at least one surface of the bridge, wherein the bridge produces stress effects measurable by an acoustic wave device located in the active acoustic region. According to one embodiment, the stress effects are measured by an acoustic wave device to sense a target matter. As target molecules accumulate on a sensing film affixed to at least a portion of the bridge, stress is produced in the bridge inducing a frequency change measured by an acoustic wave device.

Abstract: A torque sensor is disclosed based on a SAW die configured on a surface of a plate, and an isolator formed from a flexible material. The isolator is rigidly mounted to the plate, such that the isolator flexes when a force perpendicular to the surface of the plate are applied while transferring a torque that is applied within a plane of the plate to the SAW die, thereby eliminating or minimizing the effect on the SAW die of out-of-plane forces on the plate so as to isolate the torque transferred to the plate.

Abstract: An assembly, system, and method for identifying defects in a structure are provided. The assembly includes a structure of a metallic or composite material, and a flexible sheet of material positioned adjacent to the structure. The assembly also includes a plurality of non-destructive sensors secured to the flexible sheet, and a mechanism operable to impact the flexible sheet or proximate to the flexible sheet to generate stress waves within and along a surface of the structure. The system further provides a data acquisition system capable of communicating with the sensors such that the data acquisition system generates feedback indicative of at least a portion of the structure based on data from the stress waves acquired by the sensors.

Abstract: A method of forming a protection layer on a specimen for TEM inspection and a method of forming a specimen for TEM inspection are provided. The method of forming a protection layer on a specimen for TEM inspection generally comprises coating a wafer slice comprising an inspection point with a protection material and compressing the protection material to the wafer slice. The method of forming a specimen for TEM inspection generally comprises cutting a wafer slice comprising an inspection point from a wafer, forming a protection layer on the wafer slice, forming a first preliminary specimen by cutting the wafer slice, forming a second preliminary specimen by grinding the first preliminary specimen, and forming a TEM specimen by etching portions of the second preliminary specimen.

Abstract: A strain waveform control apparatus of the present invention is adapted to horizontally supporting a printed circuit board over a trestle and cause strains on the printed circuit board by a dropped rigid ball with buffer blocks being located on both surfaces of the printed circuit board. These buffer blocks are movably supported by movable stages so as to be in contact with proper places of both surfaces of the printed circuit board. The buffer blocks are capable of regulating and relatively modify/adjusting first and second occurred strain waveforms generated by application of the impact to the printed circuit board and modifying/adjusting a steepness of each of the strain waveforms.

Abstract: Methods are provided for predicting properties based on stress wave velocity measurements, such as modulus of elasticity (MOE) and/or warp potential of trees and/or logs from a timber-based raw material group (“TBRMG”). The methods provide a formula allowing compensation for growth rate differences between stands. Accordingly, the present invention prevents underestimation or overestimation of MOE and/or warp potential.

Abstract: Methods and apparatus are provided for monitoring an aircraft accessory. The apparatus comprises a processor associated with said aircraft accessory, a transducer coupled to said processor and operable to produce parametric data relating to said aircraft accessory and a memory coupled to said processor having baseline parametric data residing therein, wherein said baseline parametric data comprises the parametric data obtained during an acceptance test procedure. The method comprises installing a transducer configured to produce parametric data relating to said aircraft accessory, coupling said transducer to a processor associated with said aircraft accessory, coupling said processor to a memory associated with said aircraft accessory, recording baseline parametric data relating to said aircraft accessory in said memory during an acceptance test procedure for said aircraft accessory.

Abstract: Some O-rings can include internal flaws that can eventually lead to failure of the O-rings during use. In order to scan an internal structure of an O-ring, the present disclosure includes an apparatus with an apparatus body to which an O-ring support and a transducer assembly are attached. The transducer assembly includes an ultrasound generator that transmits ultrasound toward the O-ring to generate reflections toward an ultrasound receiver. The apparatus includes a display for comparing ultrasound receiver data with expected data. It is determined whether there are reflections of the ultrasound transmissions off of at least one internal surface within the O-ring.

Abstract: Systems and methods for measuring belt tension in a semiconductor processing system include measuring a natural sound or an acceleration of the belt in the semiconductor processing system; digitizing the natural sound or the acceleration; determining the frequency and characterizing the belt tension as a function of the frequency.

Abstract: The invention relates to a method for measuring mechanical stresses of a rotating part (1) in an essentially closed metal housing. The rotating part comprises a sensor (2) which reflects electromagnetic waves and which can be measurably deformed as a result of a mechanical stress exerted on said rotating part (1) The two antennas (A1, A2) receiving the reflected signals of the sensor (2) are arranged in the bearing housing (10) in such a way that they cannot rotate in relation to the sensor and are distanced (?). Said antennas emit receiving signals (a1,a2) which are sent to an electronic evaluation system (20,21) which measures the mechanical stresses of the rotating part (1) on the basis of both receiving signals (a1,a2).

Abstract: Brittleness of a coating substance such as a coating film that is too brittle and/or too thin to be independently removed or handled is rated on the basis of an outcome of detection of acoustic emissions which are produced when a test film piece prepared by laminating a support with the coating substance is deformed by a compression transverse test device and detected by an AE sensor attached to the test film.

Abstract: A system and method for testing at least one joint in a linkage includes a platform system, a torque system, an articulation assembly and a fault detection system. The platform system receives a first shaft connected to a first joint in the linkage and the torque system applies torque to the first joint without substantially rotating the first shaft or joint, a second shaft connected to a second joint in the linkage or the second joint. The articulation assembly receives the second shaft and moves the second joint in a substantially circular path without substantially rotating the first shaft or joint and the second shaft or joint. The fault detection system determines the condition of the linkage based upon detected signals emitted from the linkage while the first joint is torqued and the second joint is moved.

Abstract: A passive SAW strain sensor for remotely sensing strain within a surface has a receiving SAW correlator with a signal input interdigitated transducer and a plurality of adjacent successive spaced interdigitated output transducers on a piezoelectric substrate, and a transmitting SAW correlator having a plurality of adjacent successive spaced interdigitated output transducers and a signal output interdigitated transducer on a piezoelectric substrate. The transmitting SAW correlator is affixed to or embedded in the surface such that its substrate will be stressed when the surface is strained and the receiving SAW correlator is not affixed to or embedded in the surface. The output transducers of the receiving SAW correlator and the transmitting SAW correlator are spatially placed to define a unique frequency of sensitivity, and their outputs are coupled together.