The present invention relates to a safety diagnosis method for a structure using a nonlinear ultrasonic wave modulation technique. The safety diagnosis method includes: making the structure vibrate by applying signals of different ultrasonic frequencies; converting the responses of the structure generated by the vibration into digital signals; extracting first modulation signals by subtracting the harmonic responses and the linear responses of the signals of different ultrasonic frequencies from the digital signals and synchronously demodulating the digital signals; constructing a first sideband spectrogram by combining the first modulation signals generated by continuously changing at least frequency among the signals of different ultrasonic frequencies; and deciding whether the structure is cracked based on the first sideband spectrogram. Even though the power of the ultrasonic wave applied to the structure is very small as compared with the related art, whether there is the damage is precisely decided, and thus power consumption may be reduced.

A through-transmission ultrasonic (TTU) inspection system for ultrasonic inspection of a part and for determining alignment calibration data for increased alignment accuracy. The TTU inspection system may include first and second end effectors located on opposite sides of the part, each having at least one transducer for transmitting or receiving ultrasonic or sound waves through the part. The TTU inspection system may also include actuators and a system controller. The system controller may command the actuators to actuate the first end effector according to one or more scanning patterns, while the transducers send and/or receive signals to or from each other through the part. The system controller may use signal strength measurements received along these scanning patterns to determine alignment calibration data for applying to the first end effector and/or its associated actuators.

The invention relates to a device for detecting faults of a structure (STR), the device comprising a calculation unit and a plurality of transducers (100) intended to be positioned on or in the structure (STR), first transducers (E) of the plurality de transducers (100) being capable of being in an emission mode, second transducers (R) of the plurality of transducers (100) being capable of being in a reception mode,
characterized in that the first transducers (E) form a hexagonal meshing so as to delimit between them several mutually adjacent mesh cells, the second transducers (R) being positioned on respective emission circles of the first transducers (E), each emission circle of a first transducer (E) being centered on the first transducer (E).

An ultrasound sub-surface probe microscopy device (1) is provided comprising a stage (10), a signal generator (20), a scanning head (30), a signal processor (50) and a scanning mechanism (16). In use, the stage (10) carries a sample (11) and the scanning M mechanism (16) provides for a relative displacement between the sample (11) and the scanning head (30), along the surface of the sample. The scanning head (30) comprises an actuator (31) configured to generate in response to a drive signal (S.sub.dr) from the signal generator (20) an ultrasound acoustic input signal (I.sub.ac). The generated ultrasound acoustic input signal (I.sub.ac) has at least one acoustic input signal component (I.sub.ac1) with a first angular frequency (ω1). The scanning head (30) further comprises a tip (32) to transmit the acoustic input signal (I.sub.ac) through a tip-sample interface (12) as an acoustic wave (W.sub.ac) into the sample. Due to a non-linear interaction in the tip-sample interface (12) at least one up mixed acoustic signal component (W.sub.ac2) in said acoustic wave that has a second angular frequency (ω2) higher than the first angular frequency (ω1) Contrary to known approaches, the sensor signal (S.sub.sense) provided by the sensor facility is indicative for a contribution (W′.sub.ac2) of the at least one up mixed acoustic signal component in reflections (W′.sub.ac) of the acoustic wave within the sample (11). Therewith a relatively high resolution can be achieved with which subsurface features can be detected.

A method for measuring a fracture permeability and a matrix permeability of a naturally fractured cylindrical rock sample, includes sealing both flat ends of the cylindrical sample; immersing the naturally fractured cylindrical rock sample in a fluid, and attaching an axial and a radial strain sensor to the curved surface of the sample. Furthermore, the method includes attaching a signal generator to one flat end of sample, and a signal receiver to the other flat end of the sample, and generating a harmonic excitation using the signal generator at a plurality of frequencies and recording the excitation at each of the plurality of frequencies. The method includes calculating an elastic wave propagation attribute at each of the plurality of frequencies, and inverting the elastic wave propagation attribute at each of the plurality of frequencies to determine the fracture permeability and the matrix permeability of the naturally fractured cylindrical rock sample.

A membrane defect inspection method is for a membrane module set including a plurality of membrane modules connected in parallel under a straight pipe portion of gas detection piping extending in a horizontal direction and communicating with primary spaces in the plurality of membrane modules to which raw water is supplied or secondary spaces. The method includes a gas injection process where gas is injected into spaces opposite to the primary spaces or the secondary spaces communicating with the gas detection piping while the gas detection piping is filled with water, and an echo detection process where an ultrasonic sensor is brought into contact with an end portion of the straight pipe portion of the gas detection piping, and a reflected wave of an ultrasonic wave transmitted from the ultrasonic sensor is detected.

A part defect testing system includes a hammer beam system that provides laser light having a first wavelength. A read-out beam system provides laser light having a second wavelength. A control system is used to direct the generated hammer beam laser light toward a first position on a part to provide an acoustic hammer pulse that induces surface movement of the part. An areal camera is arranged to produce an interferogram derived from reading surface movement of the part using the read-out beam directed to a second position on the part.

The present disclosure relates to an ultrasonic device for real-time and nondestructive assessment of extracellular matrix stiffness, and the method of making and using the novel ultrasonic device.

An acoustic bidirectional reflectance distribution function (BRDF) measurement system utilizing metamaterials and compressive sensing for measuring scattering acoustic profiles (e.g., over large angular regions, such as hemispherical scattering/emitting into two π steradians or even spherical scattering/emitting over four π steradians). The measurement system includes one or more acoustic waveguides having a curved receiving surface and made from an acoustic metamaterial configured to encode as a sound signal a frequency and directionality of a sound input received from a sample. Each acoustic waveguide includes an acoustic sensor for detecting the encoded sound signal from the metamaterial.

The present disclosure relates to devices and methods for determining the density of insulation. For example, one aspect of the disclosure is a device that includes a first unit that includes a sound generator and a second unit that includes a sound sensor and a probe. The probe is configured to be inserted into insulation such that the sound sensor is outside of the insulation and is configured to detect sound that is generated by the sound generator outside of the insulation and transmitted through the insulation and the probe to the sound sensor. The device also includes a control system configured to cause the sound generator to generate the sound and to use the sound detected by the sound sensor to generate output that represents the density of the insulation.