A method for evaluating a target, the target having a surface, includes pulsing a defined, energetic particle beam through the surface and into the target such that particle energy deposition from the particle beam is concentrated in a subsurface target volume within a target medium of the target. The deposited particle energy induces a thermoelastic expansion of the target medium in the target volume that generates a corresponding acoustic wave. The method further includes detecting the acoustic wave from the target medium.

A method for determining a material type of an object of interest comprises: directing, using a radio frequency (RF) source, RF energy into a region of interest, the region of interest comprising the object of interest, a known reference and a boundary between the object of interest and the known reference; detecting, using an acoustic receiver, at least one thermoacoustic multi-polar signal generated in response to the RF energy; correlating, by one or more processors, the at least one thermoacoustic multi-polar signal to a transmitted power correction factor to generate a corrected thermoacoustic multi-polar signal; and determining, by the one or more processors, the material type of the object of interest as a function of the corrected thermoacoustic multi-polar signal and a transmitted power of the RF energy.

A gas sensor having a heater, a receiver, and a space arranged between the heater and the receiver, is described, the heater being configured to generate a thermoacoustic sound wave propagating through the space by using a stimulation signal. The receiver is in this case configured to receive the thermoacoustic sound wave that has propagated through the space and to convert it into a reception signal that has a time-of-flight-dependent shift with respect to the stimulation signal and therefore information relating to the gas concentration in the space.

An acoustic sensor for sensing environmental attributes within an enclosure is disclosed. The acoustic sensor may include a bulk acoustic wave (BAW) transducer configured to be installed outside the enclosure. The BAW transducer may generate an acoustic wave pulse and receive a reflected acoustic wave pulse. The acoustic sensor may further a waveguide assembly configured to be installed inside the enclosure. The waveguide assembly configured to receive the acoustic wave pulse from the BAW transducer. The acoustic sensor may further include a sensing device, wherein the sensing device may determine a change in one or more acoustic wave propagation parameters, based on the generated acoustic wave pulse and the reflected acoustic wave pulse. The sensing device may further determine one or more environmental attributes within the enclosure, based on the change in the one or more acoustic wave propagation parameters.

A detection device includes a vibration sensor configured to detect vibration of a machine, a calculation unit configured to perform FFT analysis on detection data of the vibration sensor, divide a specific frequency range into a plurality of frequency ranges, and calculate a partial overall value for each of the plurality of frequency ranges, and a wireless communication device configured to transmit the partial overall value.

A thermoacoustic transducer integrating at least one piezoelectric element having a first surface and a second surface, a potential electrode that is electrically connected to the second surface, a ground electrode that is electrically connected to the first surface, a switch electrically connected to both the potential electrode and the ground electrode, a timer configured to match a pulse emanating from a radio-frequency emitter, further wherein the potential electrode and the ground electrode are electrically connected through an impedance when the switch is in an active state, further wherein the potential electrode and the ground electrode are not electrically connected when the switch is in an inactive state; and a housing accommodating the at least one piezoelectric element, potential electrode, ground electrode, and switch.

Provided is a sensor system which can detect a thickness reduction, a crack, or the like of a pipe or a container covered with a thick coating member through ultrasonic inspection without attachment and detachment of the coating member. A sensor system used for nondestructive inspection includes a sensor attached to a surface of an inspection target, a sensor coil that is electrically connected to the sensor via a first cable, a first electromagnetic wave blocking member that is disposed between the surface of the inspection target and the sensor coil, a sensor side coil that is disposed to face the sensor coil with a gap and is coupled to the sensor coil through electromagnetic induction, and a probe side coil that is disposed to be separated from the sensor side coil and is electrically connected to the sensor side coil via a second cable.

A joint inspection system and methods of inspecting a joint in a structure are presented. In a method, an ion beam is sent, by an ion beam source, into a first surface of the structure to form an acoustic pulse source in the structure at a depth corresponding to a Bragg peak of the ion beam, wherein acoustic pulse source is adjacent to the joint. A travel time and a magnitude of an acoustic pulse generated by the acoustic pulse source is sensed, by an acoustic sensor positioned at a second surface of the structure, to thereby form a response, wherein the joint is between the acoustic pulse source and the second surface.

A photoacoustic gas sensor includes a hermetically sealed housing filled with a reference gas. The photoacoustic gas sensor furthermore includes a microphone arranged in the housing and configured to generate a microphone signal as a function of a sound wave based on light incident in the housing. Furthermore, the photoacoustic gas sensor includes a controllable heat source arranged in the housing and configured to selectively thermoacoustically excite the reference gas in order to generate a thermoacoustic sound wave phase-shifted with respect to the sound wave.

The present disclosure relates to a gas analyzer for measuring density and/or viscosity of a medium. The gas analyzer includes a connection panel having first and second media openings, each of which extends from a first surface to a second surface of the connection panel. A sensor panel is joined together with the connection panel on a first joint plane, and a cover panel is joined together with the sensor panel on a second joint plane, on a sensor panel face facing away from the connection panel. The cover panel has a cover panel cavity which communicates with the first and second media openings, and the sensor panel has at least one oscillator cavity which communicates with the first and second media openings. The sensor panel has a micromechanical oscillator arranged in the oscillator cavity and excitable to mechanically vibrate perpendicularly to the joint planes.