Devices for detecting plate bending, or flexural, waves include at least two mechanical resonators positioned on a plate in a specified configuration. Each mechanical resonator has an associated oscillation amplitude detector, such as a laser vibrometer, configured to detect resonant oscillation of the mechanical resonator in response to an incident flexural wave. A ratio of frequency-dependent oscillation data for each mechanical oscillator is compared to a calibration curve to determine the angle of incidence of the flexural wave.

Material selection systems and methods for constructing a musical instrument and/or where a selected material is a wood material are disclosed. One example material selection system includes a rating module and a rating database. The rating module includes an excitation device configured to act upon material samples; a vibration receiver in cooperation with the excitation device; a rating computer coupled to the vibration receiver, the rating computer configured to execute stored instructions for determining a set of material sample ratings based on FFT analysis of data collected by the vibration receiver; and an output device operatively coupled to the rating computer, the output device configured to output the determined set of material sample ratings to a rating database. Each set of material sample ratings is associated with a material sample. Another example material selection system may further include a selection module with a selection computer coupled to the rating database.

A surface roughness analysis system and methods of analyzing surface roughness of a workpiece are presented. The surface roughness analysis system comprises a number of wave generators; a number of wave sensors; and an ultrasonic analysis system configured to receive material mechanical parameters for a workpiece, determine incident surface wave signal parameters for a source signal to be sent by the number of wave generators, and determine a cut-off wavelength using the material mechanical parameters, wherein the cut-off wavelength is a ratio of surface wavelength over incident wavelength.

A method and an apparatus for guided-wave tomographic measurement or monitoring of wall thicknesses of the walls of pipes and similar structures are disclosed. The method is characterized in that use is made of transducers (205) preferably positioned in at least two groups of a plurality of transducers (305′-305″) arranged in a spaced apart pattern on the external surface of the structures, the transducers individually transmit ultrasound signal into the pipe wall 204, in that each ultrasound signal propagates within the pipe wall 204 from the transmitting transducer and is received at one or several receiving transducers, and the received ultrasound signal is converted to an electrical signal by the receiving transducers and recorded by the transceiver (20). Measurements are performed by using a further plurality of transducers (406, 506) that are placed apart from the two groups of a plurality of transducers (305′-305″). There is also disclosed a method for guided-wave tomographic measurement or monitoring of wall thicknesses in the walls of pipes and similar structures producing a set of measurement data by using the apparatus.

A system includes an inspection robot having an input sensor comprising a laser profiler and a plurality of wheels structured to engage a curved portion of an inspection surface, wherein the laser profiler is configured to provide laser profiler data of the inspection surface; a controller, comprising: a profiler data circuit structured to interpret the laser profiler data; determine a feature of interest is present at a location of the inspection surface in response to the laser profiler data; and wherein the feature of interest comprises a shape description of the inspection surface at the location of the feature of interest.

In some embodiments, processes for testing for structural flaws in sapphire parts such as display cover plates used in the manufacturing of electronic devices are disclosed. A process may include transmitting a destructive acoustic signal onto a sapphire part, and determining whether the sapphire part failed in response to the destructive signal. The destructive acoustic signal may include a Rayleigh acoustic wave, wherein the destructive acoustic signal breaks the sapphire part if the sapphire part has a surface flaw larger than a specified size. In this manner, only sapphire parts that can withstand the destructive acoustic signal are used in manufacturing of the electronic device.

The invention discloses a non-linear Lamb wave mixing method for measuring stress distribution in thin metal plates. The method is suitable for stress distribution detection and stress concentration area positioning in a plate structure and belongs to the field of nondestructive detection. The steps of the present invention is: first determines the excitation frequencies of two fundamental waves according to the measured object and the nonlinear Lamb wave mixing resonance conditions; the left and right ends of the test piece are oppositely excited two rows of A0 mode waves, and the excitation signal receive the sum-frequency S0 signal at a certain position to detect non-linear mixing stress of the plate structure; by changing the excitation time delay of the excitation signal, perform mixing scan on different positions of the test piece to extract the mixing wave amplitude; finally, according to the variation of amplitude of sum frequency difference signal with mixing position to realize the detection of stress distribution of metal plate and the positioning of the stress concentration area.

The present invention relates to a piezoelectric sensor (1,100) comprising a piezoelectric material (10) interposed between a first (11) and a second (12) electric contact element. The first electric contact element (11) comprises at least two sensing areas (110, 111) spatially separated along a sensing direction. It also describes a sensor node that includes the piezoelectric sensor, a system and a method for monitoring the integrity of a structure using said piezoelectric sensor.

A method of detecting inconsistencies in a structure is presented. A pulsed laser beam is directed towards the structure. A plurality of types of ultrasonic signals is formed in the structure when radiation of the pulsed laser beam is absorbed by the structure. The plurality of types of ultrasonic signals is detected to form data.

According to one implementation, an ultrasonic test system includes an ultrasonic propagating body and an optical fiber sensor. The ultrasonic propagating body changes at least one traveling direction of at least one ultrasonic wave which propagates in a test target. The optical fiber sensor detects the at least one ultrasonic wave of which the at least one traveling direction has been changed by the ultrasonic propagating body.