Abstract: A system for detecting differential bearing damages includes a synthesized tachometer that generates a tachometer signal corresponding to the race speed difference of a bearing assembly such that the bearing damage speed difference dependency can be eliminated and the damage features can be enhanced. The system also includes acceleration enveloping in the cycle domain to further enhance the damage signatures.

Abstract: The invention relates to a device for detecting and monitoring damage to races or adjacent regions of bearing rings (1, 2, 3) of anti-friction bearings. The device includes a measuring device, disposed in the anti-friction bearing chamber, having a sensor and structure for supplying sensor measurement data to the outside. The device has an energy source, which is also disposed in the anti-friction roller bearing chamber and which comprises a first coil (16) for the measuring device and a second coil (18) disposed outside the anti-friction bearing chamber and destined for inductive transfer of electrical energy to the first coil (16). The second coil (18) extends only over a part of the bearing circumference and the energy source comprises an energy accumulator (19) connected to the first coil (16).

Abstract: Device for determining displacement, the device comprising at least two substantially parallel plates located at a distance from each other. The device is arranged to determine a displacement of at least two predetermined parts of each of the plates with respect to each other and the displacement are directed substantially perpendicular to a main surface of the plates, wherein the displacement is a result of bending of the plates. The device comprises at least one sensor for measuring the displacement.

Abstract: In a nondestructive testing apparatus for testing normality of a blade root in a steam turbine installed in a nuclear plant or a thermal plant, an ultrasonic probe and an encoder can be mounted at the outside by only removing a casing of the steam turbine, without the necessity of withdrawing a turbine rotor, so that an automatic testing can be performed by rotating the steam turbine. Since the testing result can be digitally stored, reliability of the testing is improved. Furthermore, size of the testing apparatus is highly reduced for a tester to conveniently carry and install the testing apparatus alone. As a result, installation time and the whole testing time can be minimized.

Abstract: A method of measuring vibration in a bladed rotor structure with a vibration monitor. The vibration monitor includes a sensor for sensing passage of the sensor targets on radially outer portions of the blade structure, and the sensor generates signals corresponding to target passing events. An excitation structure is provided including at least one air jet for providing an excitation force to the blade structure. The blade structure is rotated about an axis of rotation and the air jet is driven in a circular path about the axis of rotation at a different rotational speed to apply a non-synchronous excitation force to the blade structure.

Abstract: An apparatus for ultrasonically inspecting a component comprises a first ultrasonic transducer for transmitting an ultrasonic signal into a component having rotational symmetry and a second ultrasonic transducer for detecting the reflected, or transmitted, ultrasonic signal. A motor and a turntable produce relative rotation between the rotationally symmetrical component and the first and second transducers. Motors, a carriage and tracks on a frame provide relative radial motion between the rotationally symmetrical component and the first and second transducers to scan the whole of a surface of the rotationally symmetrical component. An ultrasonic signal analyzer analyses the detected ultrasonic signal by monitoring for ultrasonic signals having an amplitude above a predetermined amplitude and not having rotational symmetry and a display provides an indication that any detected ultrasonic signals above the predetermined amplitude and not having rotational symmetry is a potential flaw in the component.

Abstract: A method, system and program storage device are provided for machine diagnostics, detection and profiling using pressure waves, the method including profiling known sources, acquiring pressure wave data, analyzing the acquired pressure wave data, and detecting if the analyzed pressure wave data matches a profiled known source; the system including a processor, a pressure wave transducer in signal communication with the processor, a pressure wave analysis unit in signal communication with the processor, and a source or threat detection unit in signal communication with the processor; and the program storage device including program steps for profiling known sources, acquiring pressure wave data, analyzing the acquired pressure wave data, and detecting if the analyzed pressure wave data matches a profiled known source.

Abstract: A method for detection and quantitative evaluation of a balance error occurring in a component-bearing system. Static and dynamic forces acting upon the bearing are determined by sensors of a measuring bridge, which are disposed on a rolling bearing and which change the inherent electrical resistance according to the applied pressure, and are made available for analysis in a computer in the form of a periodic test signal that is common to both forces. In order to analyze the test signal, the weighted average of the modulation frequency generated by a balance error and the weighted mean variance thereof are determined from the test signal. The variance is then compared with a given variance threshold value. A variance lying below the variance threshold value is considered to be an indication of a significant balance error in the bearing.

Abstract: A method of measuring one or more motion parameters of a main shaft in a gyratory or cone crusher is disclosed. Signals are directed from a stationary sensor means located apart from the main shaft to one or more signal reflective surfaces situated on a target located on or adjacent to an upper portion of the main shaft. The target rotates and otherwise moves in unison with the movement of the main shaft. From the elapsed time the distances from the sensor the reflective surfaces on the target are determined. Analyzing the distances over time will yield information on the movement of the main shaft.

Abstract: Provided are an envelope processor 103, for obtaining an envelope for a detected signal; a FFT unit 104, for converting the envelope into a frequency spectrum; a peak detector 105, for smoothing the frequency spectrum by calculating a moving average, for further performing smoothing and differentiation for the spectrum, and detecting, as peaks, frequency points at which a sign of a differential coefficient is changed from positive to negative, for extracting peaks having a predetermined threshold value or greater, and for sorting the extracted peaks and detecting upper peaks; and a diagnosis processor T, for diagnosing an abnormality based on the detected peaks.

Abstract: An automated scanning system and method, utilizing specialized dual phased array ultrasonic transducers for producing and detecting Rayleigh waves in ceramic bearing balls are provided for nondestructive, non-contact inspection of ceramic bearing balls. The phased array ultrasonic transducer utilizes a complex curvature configuration that enables the dual phased array ultrasonic transducers to focus ultrasonic energy onto the ball to optimally generate and receive Rayleigh wave signals in the spherical objects.

Abstract: A method for detecting structure-borne noise events in a roller bearing, wherein a measuring signal M of a pressure or dilatation sensor arranged on a roller bearing is fed to a frequency filter for filtering out undesired signal parts. A first variance value is calculated from digital values of the frequency filter output signal and at least one second variance value is calculated from other digital values of the frequency filter output signal and a weighted arithmetic average of the at least two variance values is calculated with the aid of a recursive calculation of the variance value. If the weighted arithmetic variance average value exceeds a pre-selected variance threshold value, then it is assessed that a structure-borne noise event provoked by mechanical damage to the roller bearing has occurred.

Abstract: An anomaly diagnosis apparatus for analyzing sound or vibration data produced by a machine installation and diagnosing the presence or absence of an anomaly in a sliding member in the machine installation which is made up of a diagnosis processing server (1) and a user information processing terminal (3) which are connected through a network (2). The diagnosis processing server (1) receives the sound or vibration data produced by the machine installation and information for identifying the sliding member used with the machine installation through the network (2) from the user information processing terminal 3, makes an anomaly diagnosis of the machine installation based on the received data, and transmits the diagnosis result through the network (2) to the user information processing terminal (3), thereby lightening the burden of the user and executing anomaly diagnosis processing promptly.

Abstract: A system and method for monitoring operation of a press assembly includes establishing a baseline vibration level for a first location on the press assembly. The baseline vibration level defines a boundary for vibrations beyond which one or more press elements have a reduced life expectancy. Vibrations are measured at the first location and also at a second location during operation of the press. The vibrations measured at the first location are correlated with the vibrations measured at the second location, and a relationship between the vibrations at the first and second locations is established. Vibrations measured at the second location can then be adjusted and compared to the baseline vibration level to determine if adjustments to the press operation need to be made, or if certain press elements will need to be replaced prior to their expected life span.

Abstract: A state detecting apparatus S for detecting a current operating state of an LM (linear motion) system includes an AE sensor 1 generating a detection signal Sae by detecting an AE wave elastically generated when a plurality of balls contained in the LM system revolve in a circulation portion while spinning themselves; and a signal processing unit 4 generating a parameter indicating an intensity of the AE wave based on only the detection signal Sae corresponding to an operating frequency of the ball, and uses the parameter to determine a lubrication state of the LM system. Thereby, it is possible to provide the state detecting apparatus capable of predicting failure occurrence in the LM system; providing an improved maintenance to a user of the LM system and further longer lifetime thereof; and providing a performance guarantee and an improved quality of a device or equipment manufactured using the LM system.

Abstract: The invention relates to a method for the analysis of bearing damages by means of an envelope demodulation signal, at least one variable of the envelope demodulation signal that is characteristic of the occurrence of bearing damages being determined. The invention is characterized in that the characteristic variable is repeatedly determined during a plurality of predetermined intervals and these intervals are shorter than the intervals between external disturbances.

Abstract: Modeling and simulation of free and forced structural vibrations is essential to an overall structural health monitoring capability. In the various embodiments, a first principles finite-difference approach is adopted in modeling a structural subsystem such as a mechanical gear by solving elastodynamic equations in generalized curvilinear coordinates. Such a capability to generate a dynamic structural response is widely applicable in a variety of structural health monitoring systems. This capability (1) will lead to an understanding of the dynamic behavior of a structural system and hence its improved design, (2) will generate a sufficiently large space of normal and damage solutions that can be used by machine learning algorithms to detect anomalous system behavior and achieve a system design optimization and (3) will lead to an optimal sensor placement strategy, based on the identification of local stress maxima all over the domain.

Abstract: Degradation of the lubricant due to contamination of the lubricant with wear particles or moisture, which greatly affects the service life of rolling bearings, can be detected in a cost-effective manner through the use of a resonance frequency band signal or high-frequency signal of an accelerometer, and the service life of a rolling bearing can be estimated with high precision at an early stage on the basis of the detected state of the wear particles and lubricant.

Abstract: A system may be used to indicate a need for replacement of a vibrating structure and includes a sensor, an indicator, and a processor. The sensor senses a frequency of vibration of the vibrating structure. The indicator is controlled to provide an indication of the need for replacement of the vibrating structure. The processor compares the frequency of vibration of the vibrating structure to data that relates the vibration frequency of the vibrating structure to fatigue damage of the vibrating structure, and controls the indicator based on the comparison.

Abstract: An apparatus surely measures the vibration characteristic of a head gimbal assembly and has a wide range of resonance frequencies to be set, the apparatus has a first laser Doppler vibrometer to detect a vibration velocity of a shaker, a second laser Doppler vibrometer to detect a vibration velocity of a head of the head gimbal assembly fixed to a fixture, and a reflection mirror to orthogonally reflect a laser beam emitted from the first laser Doppler vibrometer toward the fixture fixed to the shaker, and the apparatus finds the vibration characteristic of the head gimbal assembly according to the detected vibration velocities.

Abstract: A device for attachment to a motor vehicle wheel includes an arrangement which, during movement or driving of the motor vehicle, detects vibrations which occur, evaluates the vibrations for an incipient fault state of a wheel bearing of the vehicle wheel, and delivers a signal when the monitoring or evaluation yields or indicates the incipient fault state.

Abstract: Single-crystal components of gas turbine engines, like turbine blades, are inspected in the installed state within the engine for cracking in certain critical areas using longitudinal ultrasonic waves. A first, rough orientation of the ultrasonic waves onto the critical area is accomplished under camera-visual control using an ultrasonic probe whose shape conforms to the respective component area and which, therefore, can be form-fitted to the component. For fine-positioning of the ultrasonic waves in the critical area, a reference signal is generated at a component-specific geometrical contour adjacent to the critical area by second ultrasonic waves emitted at a local distance to the first ultrasonic waves. The presence of this signal ensures the safe, disturbance-free detection of cracks in the critical blade area by means of longitudinal sonic waves. The invention includes an apparatus for the performance of the method.

Abstract: A method for evaluating the reliability of steel in terms of small and medium-sized inclusions as well as large inclusions, and a high-reliability steel obtained by the method. The method is for evaluating the reliability of steel in terms of inclusions and is characterized in that the inclusions of approximately 100 ?m or less in maximum inclusion size are evaluated by microscopy combined with the extreme-value statistical analysis; the inclusions of approximately 100 ?m or greater in maximum inclusion size are evaluated by the ultrasonic flaw detection testing performed at a frequency of 5 to 25 MHz; and the reliability of the steel is evaluated based on the results of the extreme-value statistical analysis applied to the results of the microscopy and the results of the ultrasonic flaw detection testing combined.

Abstract: Provided is a bearing state diagnostic apparatus in which a sound generated from a bearing is detected by a sound sensor, a detected value of the sound sensor is compared with data which was previously formed, thereby diagnosing a state of the bearing, wherein at least one sound sensor is disposed at a position separated away from an outer surface of a cylindrical support body in which at least one bearing is accommodated, the corresponding bearing and sound sensor are in communication with each other through a detection sound propagation path.

Abstract: A method for predicting bearing failure of a differential bearing including an inner race, an outer race, and a plurality of rolling elements positioned between the inner and outer race, the method includes coupling a measuring apparatus comprising at least one of a strain gage and an accelerometer to the differential bearing, coupling a cable to the measuring apparatus, wherein the cable is adapted for passage through a rotating component, and coupling a transmitter to the cable, wherein the transmitter is configured to transmit a plurality of signals from the measuring apparatus to a remote location to facilitate predicting a failure of the differential bearing.

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: In a shaft coupling monitoring apparatus for monitoring a spider joint using outer peripheries of four shafts of a cross shaft as rolling contact surfaces, each of the shafts contains therein a sensor for detecting any damage on the rolling contact surface thereof. Even in a case where the spider joint is incorporated in a driving shaft such as of a rolling mill, the monitoring apparatus may provide high-accuracy and early detection of any damage such as flaking on the rolling contact surface defined on each of the shafts of the cross shaft.

Abstract: An apparatus of producing bearing device having a bearing, a shaft attached to an inner ring and an outer ring attaching member attached to an outer ring. The apparatus includes a vibrating unit of giving a radial input vibration to each inner ring or both ends of the shaft, and an input vibration detecting unit of detecting vibration of each inner ring or both ends of the shaft, an adding unit of calculating the output of the input vibration detecting unit, a vibration detecting unit of detecting the vibration of a mass attached to the outer ring attaching member, a transfer function calculating unit of determining the transfer function from the output of the vibration detecting unit and the adding unit to calculate the resonance frequency and a rigidity calculating unit of determining the rigidity of the bearing device on the basis of the resonance frequency.

Abstract: A diagnostic vibration analyzing system and method for measuring and characterizing both linear and torsional vibrations in a vehicle or a piece of industrial equipment (collectively a “vehicle”). An electronic control unit and a plurality of sensors cooperate to measure accelerations sensed by a vehicle operator. These measured accelerations, when combined with sensed rotational velocities, can be used to pinpoint likely sources of driveline vibrations. Once the sources of driveline vibrations are identified, they are graphically displayed to a user for remedial action.

Abstract: A fuel injector testing system and method that make accurate determination of the condition of an injector installed in an engine possible even if the injector is hidden under or behind engine components. A waveguide attached to the injector guides stress waves generated when the injector pintle is opened or closed to a location on the engine that is accessible by a technician. A stress-wave sensor attached to the accessible end of the waveguide measures the stress-wave intensity and plots on a display its magnitude vs. time. A technician testing a fuel injector can read from the display the numerically accurate impact intensities and the precise timing of the injector pintle opening and closing movements. The display can also compute automatically the values of the impact intensities and the length of time that the injector valve was open. This allows the technician to quickly detect a faulty injector.

Abstract: A method for predicting bearing failure, wherein the bearing includes an inner race, an outer race, and a plurality of rolling elements between the inner and outer race. The method includes coupling a sensor assembly to the outer race, the sensor assembly including at least one temperature sensor and at least one acoustic sensor, generating a bearing performance model based on an initial signal received from the sensor assembly, receiving a second signal from the sensor assembly, and comparing the second signal to the bearing performance model to predict a bearing failure.

Abstract: The invention relates to a method of detecting damage in a bearing supporting at least one rotary shaft of an engine in rotation, the method consisting in: defining a measurement period corresponding to a range of speeds of rotation of the shaft during renewable activity at low speeds of operation of the engine; acquiring over the entire measurement period a vibratory signal representative of acceleration of components of the engine; sampling the vibratory signal as a function of the speed of rotation of the shaft during the measurement period; transforming the sampled vibratory signal into a frequency signal to obtain frequency spectrum lines as a function of the speed of rotation of the shaft; calculating the mean of the amplitudes of the spectrum lines; determining amplitude peaks around multiples of the theoretical frequency of a damaged roller; calculating the ratio between each amplitude peak and the amplitude level determined for a sound bearing; and comparing the ratio that is obtained with at least o

Abstract: The invention relates to a method and a test and analytical device for categorizing antifriction bearing damages. The invention is characterized in that analysis preceding categorization comprises statistically evaluating the jerk of a structure-borne noise signal to which the movement of the antifriction bearing to be inspected contributes.

Abstract: An embodiment of the disclosed method and apparatus relates to a system for detecting a rub in a turbomachine. The system includes a turbomachine; sensors monitoring turbomachine conditions; and an on site monitor in communication with the sensors, and loaded with instructions to implement a method for detecting a rub in the turbomachine.

Abstract: A system and method for monitoring operation of a press assembly includes establishing a baseline vibration level for a first location on the press assembly. The baseline vibration level defines a boundary for vibrations beyond which one or more press elements have a reduced life expectancy. Vibrations are measured at the first location and also at a second location during operation of the press. The vibrations measured at the first location are correlated with the vibrations measured at the second location, and a relationship between the vibrations at the first and second locations is established. Vibrations measured at the second location can then be adjusted and compared to the baseline vibration level to determine if adjustments to the press operation need to be made, or if certain press elements will need to be replaced prior to their expected life span.

Abstract: A precision sensor assembly for rotating members in a machine tool comprises a rotor unit (16) rigidly fixed to a rotor portion (2a) of the machine tool and including a sensor (5) for detecting vibrations produced by the operation of the machine tool, the sensor (5) comprising a piezoelectric sensitive element (6) and members (7, 8) for mechanical amplification of the vibrations. The members (7, 8) comprise at least one resonant system composed of an elastic element (8) and a counter-mass (7) acting on the piezoelectric sensitive element (6). The rotor and stator units (16, 17) comprise inductively coupled transmitting and receiving elements (10, 11) for transferring the signals from the piezoelectric element (6) contactless to the stator unit (17). The stator unit (17) may include an electric amplifier (13) for further amplifying the transmitted signals.

Abstract: The invention relates to a method and a device for identifying a damaged bearing (4a, 4b) of a rotating shaft (1). According to the invention: the rotational speed (n) of the shaft (1) is determined; the alternating component (nAC) of the rotational speed (n) is determined, together with a smooth curve (h) of said alternating component (nAC) of the rotational speed (n); the smooth curve (h) is converted into the frequency range and a frequency response (B) of the value of the smooth curve (h) is determined. Said frequency response (B) of the value of the curve is monitored for the passing of a threshold value (G1, G2, G3, G4) and if said threshold value (G1, G2, G3, G4) is exceeded, a damaged bearing (4a, 4b) is identified. The invention thus provides a method and a device for identifying a damaged bearing (4a, 4b) of a rotating shaft (1) of a motor, which do not require a vibration sensor (11) to identify a damaged bearing (4a, 4b) of said shaft (1).

Abstract: A device for indicating a beat level L, the device including an analyzer which responds to a reference frequency ? and a harmonic coefficient B to extract from an evaluation signal E a first acceleration signal ?B at a frequency equal to the product of reference frequency ? multiplied by harmonic coefficient B; and a second acceleration signal ?B-1 at a frequency equal to the product of reference frequency ? multiplied by the harmonic coefficient minus one; and it further includes a control circuit CC which receives acceleration signal ?B, ?B-1 to produce beat level L.

Abstract: A valve monitoring system includes an alert generation system and a memory. The memory encodes baseline acoustic emission data on the valve for a predetermined period of operation. The alert generation system is arranged to receive acoustic emission data for the valve, compare the received acoustic emission data for the valve with the baseline acoustic emission data encoded in the memory and identify valve anomalies in dependence on differences in the received acoustic emission data and the baseline acoustic emission data.

Abstract: The present invention provides a device and method of non-destructively monitoring reactive material through a substrate for changes in material properties that designate the condition of the reactive material during cure and service life. A transducer is placed on a portion of the substrate generally parallel to an interface of the substrate to the reactive material. The ultrasonic waves generated via the transducer are used to detect reflected sound waves upon encountering the interfaces, where the interfaces consist of changes in material properties across the substrate.

Abstract: A vibration sensor (1) for monitoring the state of rotating components or bearings, includes a housing (2), a sensor element (3), evaluation electronics (4), and at least one interface (5, 6). With the vibration sensor (1), reliable monitoring of the state of rotating components and bearings can be done easily and economically, and in addition the vibration sensor can be easily operated. The evaluation electronics (4) has an analog-to-digital converter (7), and a signal conditioning device (8) having a plurality of signals, which have been acquired by the sensor element (3), and which are converted into a state value using signal analysis and a diagnosis algorithm.

Abstract: A forced harmonic vibration master gear for use in a device for detecting imperfections in a production gear includes a gear body having a plurality of gear teeth. Each of the plurality of gear teeth has a graduation of material added thereto extending from a form diameter of each tooth to an end of the tooth to decrease the pressure angle of the tooth. The forced harmonic master gear when used to test an unacceptable production gear, induces in the unacceptable production gear, when rotating, a vibrational force that is at least 50 percent greater than a vibrational force exhibited by the unacceptable production gear when a standard master gear is used to test the unacceptable production gear, in at least one band of 70 Hz to 150 Hz, 151 Hz to 300 Hz, 301 Hz to 550 Hz, 551 Hz to 1250 Hz and 1251 Hz to 2000 Hz.

Abstract: A toroidal-type continuously variable transmission component, such as an input disk, an output disk, an inner ring of a power roller bearing, and an outer ring of the power roller bearing, which is functioned as a rolling member, has a layer a depth of which is 0.5 mm or less from the surface thereof. The layer does not include a non-metallic inclusion having a maximum diameter of up to 0.1 mm in the area thereof having a depth of 0.5 mm or less from the surface thereof.

Abstract: A vibration information transmission apparatus for improving efficiency of field wiring of a vibration monitoring/analyzing system includes transmitters (11-1 to n) for converting vibration information from vibration sensors (2-1 to n) for detecting vibration of an object to be measured, into an electric signal and outputting the electric signal to a digital network (DN). The transmitters (11-1 to n) includes in the same casing, a transducer circuit (18) for converting the vibration information from the vibration sensors (2-1 to n) into an analog electric signal, an A/D conversion circuit (19) for converting the analog electric signal from the transducer circuit (18) into a digital signal, and a network interface (20) for outputting the digital signal from the A/D conversion circuit (19) to the digital network (DN).

Abstract: A structurally tuned, vibration-based component checking system for detecting anomalies in a component of an assembly prior to the component being installed in the assembly is provided. The component checking system operates the component being tested at a speed that is different from the speed at which the component operates during normal use in the assembly, and also under a different load. To compensate for this difference in speed and load, the component checking system is structurally tuned such that a relationship exists between the modal frequencies and speed of operation of the component checking system and the modal frequencies and speed of operation of the assembly.

Abstract: A measuring system for structure-born noise measurement of machine elements in machine housings. The measuring system is fixed to the machine housing via a lubrication hold opening. A mounting pin with a continuous bore hole. A housing receives a printed circuit board provided with electronic components for signal evaluation. A vibration snesor and vibration sensor housing rotationally mounted in relation to the mounting pin when the mounting pin is screwed into the lubrication hold opening. The vibration sensor housing is rotationally fixed to the machine housing in a non-positive fit via a metal bushing when the mounting pin is screwed in an end position. The vibration sensor is located adjacent to the metal bushing whereby structure-born noise is directly transferred from the machine housing to the vibration sensor via the metal bushing.

Abstract: A sensor unit is supported on a stationary ring which does not rotate even when it is in use, and the rotation of the rotary ring can be detected by a rotation detecting sensor held within the sensor unit. Within the sensor unit, besides the rotation detecting sensor, there are disposed other sensors such as a temperature sensor and a vibration sensor, thereby being able to detect the rotation speed and the rotation number of the wheel supported on the rotary ring, and the other car driving conditions.

Abstract: A bearing vibration measuring apparatus is an apparatus of measuring vibration of a bearing. The bearing vibration measuring apparatus detects a vibration component generated from the bearing in a state of pressing one of an inner ring and an outer ring of the bearing in an axial direction while relatively rotating other of the inner ring and the outer ring to detect a defect of the bearing based on the vibration component. The bearing vibration measuring apparatus includes a driving mechanism elongated and contracted for inclining the inner ring or the outer ring.

Abstract: A method for detecting vibration signatures in a reversible drive is disclosed. The method includes the steps of acquiring digital data representative of vibrations in the reversible drive and identifying and grouping together portions of data in a plurality of groups. The identified portions of data relate to a particular direction of travel of the reversible drive and the plurality of groups relate to travel in different directions of the reversible drive. The method can include the further step of processing at least one of the groups of data using signal processing techniques. A system and computer program product for practicing the method for detecting vibration signatures in a reversible drive are also disclosed.

Abstract: A method of monitoring the condition of a thermal barrier coating on a turbine blade or vane during operation of the turbine is provided. The method includes providing a means for receiving acoustic output of the blade or vane during operation of the turbine and monitoring the acoustic output over time, to determine the condition of the thermal barrier coating on the blade or vane. The acoustic output arises from a force on the blade or vane, such as that due to impact of particles, a pulse of gas pressure or constant gas flow. An apparatus employing the above method for monitoring the condition of the thermal barrier coating during operation of the turbine, is also provided.