A method for calibrating an ultrasonic sensor includes: transmitting a first ultrasonic signal from the ultrasonic sensor toward a first surface of a contact device when a model is on the first surface of the contact device; generating ultrasonic images by sampling a first ultrasonic echo signal, the first ultrasonic echo signal comprising a reflected signal of the first ultrasonic signal, at a plurality of reception time points; detecting portions of the ultrasonic images, wherein detected portions of the ultrasonic images are most similar to corresponding portions of a reference image of the model compared to other portions of the ultrasonic images having same positions as the detected portions and detected at different reception time points of the plurality of reception time points than the detected portions; and storing the reception time points corresponding to the detected portions of the ultrasonic images.

An ultrasonic scanner acquires a gain profile including gain values for corresponding travel times in ultrasonic echoes reflected by a reference object. An ultrasonic probe signal is sent toward a test object. In response, an ultrasonic echo reflected by the test object is received at the scanner. A time of arrival of the echo is estimated. The gain profile is aligned with the echo according to the estimated time of arrival of the echo. The echo is amplified using the aligned gain profile and the amplified echo is digitized before being attenuated using the aligned gain profile. An actual time of arrival of the echo is calculated based on the attenuated digitized echo. The gain profile is re-aligned with the attenuated digitized echo according to the actual time of arrival of the echo. The attenuated digitized echo is re-amplified using the re-aligned gain profile to obtain a gain-corrected echo.

Unmanned Aerial Vehicles (UAVs) are provided with hammers having contact surfaces to produce acoustic signals in structures to be inspected. By selecting a suitable flight path, the contact surface can be dragged across or tapped against the structure to produce acoustic signals indicative of structure condition. Acoustic detectors are coupled to the UAV to produce detected acoustic signals that can be stored, communicated, and/or processed to access to arbitrary structure surfaces, including bottom surfaces of bridge decks and to locate delaminations.

Method and system for ultrasonic characterization of a medium Method for ultrasonic characterization of a medium, comprising generating a series of incident ultrasonic waves, generating an experimental reflection matrix Rui(t) defined between the emission basis (i) as input and a reception basis (u) as output, determining a focused reflection matrix RFoc(rin, r.sub.out, at) of the medium between an input virtual transducer (Win) calculated based on a focusing as input to the experimental reflection matrix and an output virtual transducer (TVout) calculated based on a focusing as output from the experimental reflection matrix, the responses of the output virtual transducer (TVout) being obtained at a time instant that is shifted by an additional delay 6t relative to a time instant of the responses of the input virtual transducer (TVin).

A structure including a substrate and a coating over the substrate is acoustically excited to measure acoustic response in the structure. The measured acoustic response in the structure is filtered to remove acoustic response of the substrate and determine acoustic response of the coating. The acoustic response of the coating is used to inspect the coating for failure.

A method for non-destructive testing of a mechanical part by a multi-element transducer having piezoelectric elements, where: for each element e(i) of the transducer, the emission of an ultrasonic wave at a given frequency and measurement, by each element e(j) distinct from the element e(i), of a time-varying signal kij(t) representing the back-scattered ultrasonic wave received by the element e(j); the determination of a first matrix of time-varying components based on measured signals kij(t), i, j=1, . . . , N; the determination of a second matrix of frequency components corresponding to a determined frequency based on the frequency of the ultrasonic wave by applying a Fourier transform to said first matrix; the filtering of said second matrix comprising a projection of it onto a single scattering sub-space determined by means of a numerical calculation using a ray tracing algorithm; and the verification of the integrity of the mechanical part by using said filtered second matrix.

According to one embodiment, a structure evaluation system according to an embodiment includes a plurality of sensors, a position locator, and an evaluator. The plurality of sensors detect elastic waves. The position locator locates positions of elastic wave sources by using the elastic waves among the plurality of elastic waves respectively detected by the plurality of sensors having an amplitude exceeding a threshold value determined according to positions of the sources of the plurality of elastic waves and the positions of the plurality of disposed sensors. The evaluator evaluates a deteriorated state of the structure on the basis of results of the position locating of the elastic wave sources which is performed by the position locator.

According to one embodiment, an estimation device includes a processor. The processor accepts information. The information is acquired by each of a plurality of ultrasonic sensors transmitting an ultrasonic wave in a second direction toward a weld portion and receiving a reflected wave. The ultrasonic sensors are arranged in a first direction. The second direction crosses the first direction. The processor estimates a range of the weld portion in the second direction based on an intensity distribution of the reflected wave in the second direction. The processor calculates a centroid position of an intensity distribution of the reflected wave in the first direction for each of a plurality of points in the second direction, and estimates a range of the weld portion in the first direction based on a plurality of the centroid positions.

A dual channel nondestructive testing method for a rock bolt and related devices includes: determining a target phase difference and an instantaneous phase difference of the first received signal and the second received signal; determining an integral instantaneous phase difference between the first received signal and the second received signal based on the target phase difference and an instantaneous phase difference; determining a length of the exposed section of the rock bolt, a length of the rock bolt and a position of a grouting defect based on the integral instantaneous phase difference, a first velocity of the acoustic signal propagating in an exposed section of the rock bolt and a second velocity of the acoustic signal propagating in an anchor section of the rock bolt.

A device for particle sensing is disclosed. The device includes a sensor including a bulk acoustic wave resonator having a resonant frequency, an acoustic mirror arranged to support the resonator, and a heater in thermal communication with the resonator such that a resonator temperature is based on a heater temperature. The device also includes circuitry connected to the sensor. The circuitry comprises a driver configured to drive the heater with a driver signal having a constant periodic cycle, and an oscillator configured to generate an output signal indicative of the resonant frequency. The resonant frequency is modulated by the resonator temperature.