A modal vibration analysis system and corresponding method is provided. Exciters are coupled to a structure under test for generating vibrations in the structure. Sensors are coupled to the structure at multiple locations for sensing vibrations generated in response to the excitations. A controller provides drive signals to the exciters such that the sensor signals have a target output spectrum with specified characteristics in multiple designated frequency domains of the spectrum, characterized by a random phase for each frequency. Modal analysis processes digitized sensor signals with a Fast Fourier Transform conducted at two or more specified data sampling rates to synthesize a spectrum containing data points with finer frequency resolution for lower frequency range, and regular frequency resolution for higher frequency range. From the multi-resolution spectra, natural frequencies and damping coefficients are determined at each mode, and a mode shape at each natural frequency is computed.

Systems and methods for inspecting or characterizing samples, such as by characterizing patterned features or structures of the sample. In an aspect, the technology relates to a method for characterizing a patterned structure of a sample. The method includes directing a pump beam to a first position on a surface of the sample to induce a surface acoustic wave in the sample and directing a probe beam to a second position on the sample, where the probe beam is affected by the surface acoustic wave when the probe beam reflects from the surface of the sample. The method also includes detecting the reflected probe beam, analyzing the detected reflected probe beam to identify a frequency mode in the reflected probe beam, and based on the identified frequency mode, determining at least one of a width or a pitch of a patterned feature in the sample.

A bonding layer evaluation system includes an elastic wave generation device configured to generate an elastic wave from a sample including a bonding layer; an elastic wave reflection body configured to reflect the elastic wave generated from the sample; a sample installation unit provided between the elastic wave generation device and the elastic wave reflection body; an elastic wave detection device disposed in a direction in which the elastic wave is reflected by the elastic wave reflection body, and configured to detect the reflected elastic wave; and a control device configured to evaluate a parameter related to the bonding layer. The control device evaluates the parameter related to the bonding layer by comparing the actual value of the elastic wave detected by the elastic wave detection device with a theoretical value of the elastic wave calculated based on a theoretical model related to the sample.

A method for the ultrasonic double-wave measurement includes: obtaining a first mode wave time-of-flight and a second mode wave time-of-flight of an ultrasonic double-wave of a solid material at a first temperature and stress state; measuring a first mode wave time and a second mode wave time of the ultrasonic double-wave of the solid material in an unknown state; obtaining a first mode wave temperature influence coefficient and a second mode wave temperature influence coefficient of the solid material, and a first mode wave pre-tightening force influence coefficient and a second mode wave pre-tightening force influence coefficient in the solid material to be measured having the same specification and geometric shape; and obtaining a relative change relationship of ultrasonic double-wave time-of-flight according to the first-order or second-order Taylor approximation, and jointly solving to obtain a measured pre-tightening force and a measured temperature.

The invention disclosed herein generally relates to a device and methods to authenticate the composition of materials, including, but not limited to gold and silver coins and gold and silver bars. The invention stimulates the natural frequencies of the tested object and then compares them to a reference dataset to confirm its authenticity. It achieves this through use of a transducer that both vibrates the object and collects amplitude response, allowing for consistent and highly accurate analysis across a broad spectrum, including ultrasonic frequencies.

A system and method for analyzing structural heath data includes a structural body, structural health sensors, and first and second computer systems. The structural health sensors are configured to sense data regarding structures of the structural body. The first computer system is configured to collect the sensed data as the structural health data. The second computer system that includes a user interface and display, and is configured to receive the structural health data and provide interactive transformational analysis of the structural health data. The interactive transformational analysis provides, on the display of the second computer system, a visual representation of the structural health data over time.

A modal vibration analysis system and corresponding method is provided. A set of one or more exciters is coupled to a structure under test for generating vibrations in the structure. A set of sensors are coupled to the structure at multiple locations for sensing vibrations generated in the structure in response to the excitations. A controller receives sensor signals corresponding to the sensed vibrations from the set of sensors and provides drive signals to the set of exciters such that the sensor signals have a target output spectrum with specified characteristics in multiple designated frequency domains of the spectrum, characterized by a random phase for each frequency. Modal analysis processes digitized sensor signals with a Fast Fourier Transform conducted at two or more specified data sample rates to synthesize a spectrum containing data points with higher resolution for lower frequency range, and regular resolution for higher frequency range. From the multi-resolution spectra, natural frequencies and damping coefficients are determined at each mode, a mode shape at each natural frequency is computed using all measured data from all sensor locations.

A dialysis machine (e.g., a peritoneal dialysis (PD) machine) can include a pressure sensor mounted at a proximal end of a patient line that provides PD solution to a patient through a catheter. During treatment, an occlusion can occur at different locations in the patient line and/or the catheter. Elastic waves may be generated at a pump that introduces (e.g., for fill cycles) or withdraws (e.g., for drain cycles) the solution into/out of the patient line. For example, when the solution is introduced or withdrawn suddenly, elastic waves travel distally down the patient line until they encounter the occlusion, and are then reflected back (e.g., toward the pressure sensor).

The invention relates to a method or operating mode which, using a device for emitting and receiving sonic and/or ultrasonic torsional waves, can be used to obtain data relating to the consistency or elasticity of quasi-incompressible solid media, preferably quasi-fluids or biological tissues, based on the separation of non-linear parameters.

An ultrasonic inspection method that includes arranging an ultrasonic transmission element and an ultrasonic reception element symmetrically in relation to a straight line in a diameter direction orthogonal to the cylinder axis of a cylindrical inspection object, the inspection object being interposed between the ultrasonic transmission element and the ultrasonic reception element; transmitting ultrasonic waves from the ultrasonic transmission element at a plurality of positions in the diameter direction; receiving by the ultrasonic reception element the ultrasonic waves transmitted from the ultrasonic transmission element and transmitted through the inspection object by propagating through the inside of the inspection object; and inspecting the inspection object on the basis of a reception signal of the ultrasonic waves received by the ultrasonic reception element.