An ultrasonic-based system includes a transmitter and receiver, an ultrasonic transducer including piezoelectric element having a matching layer thereon connected to the transmitter. A controller is coupled to the transmitter. The transmitter is for driving the piezoelectric element with a pulsed electrical signal, where the piezoelectric element transmits a transmit ultrasonic signal. A current/voltage measurement circuit is coupled to sense a current or voltage in the transmitter. The controller is for implementing an algorithm for an ultrasonic transducer monitoring method including comparing an amplitude of the pulsed signal to a predetermined limit. When the pulsed signal is determined to be outside the limit, an impedance of the piezoelectric element is determined to be abnormal. When the pulsed signal is within the limit, the amplitude of the received signal is compared to a lower limit, which when below results in determining a cleaning operation for the ultrasonic transducer is needed.

An assembly including: a printed circuit board (PCB) having a first surface and a second surface; at least one energy transmitter mounted on the first surface; at least one cooling element associated with the PCB second surface, wherein the cooling element is configured to cool the at least one energy transmitter via the PCB.

An ultrasonic transducer having a piezoelectric element for use on a vehicle is disclosed. The transducer has a control and evaluation circuit for generating a control voltage for the piezoelectric element, which generates and emits an ultrasonic signal based on the control voltage, and for outputting an output signal on the basis of an echo signal received at the piezoelectric element. A gyrator circuit is included for providing a compensation inductance for adapting the control and evaluation circuit, for compensating for a parasitic connection capacitance of the piezoelectric element. The gyrator circuit has a variable compensation inductance. A method for compensating for an ultrasonic transducer having a piezoelectric element for adapting a reception sensitivity is also disclosed. The method involves recording a measurement variable for adapting the reception sensitivity, and compensating for the ultrasonic transducer by changing the compensation inductance of the gyrator circuit based on the recorded measurement variable.

An acoustic levitation system contains an acoustic transducer array emitting acoustic energy of periodically varying intensity. The acoustic transducer array includes a set of transducer elements arranged on a surface extending in at least two dimensions. The transducer elements are controllable in response to a control signal so as to emit the acoustic energy at a wavelength and a phase delay determined by the control signal. A controller generates the control signal such that an acoustic channel comprising one or more high-pressure region enclosing a continuous pressure minimum region that extends along a defined channel path from a start position to an end position. The continuous pressure minimum region enclosed by the one or more high-pressure region represents a trap volume suitable for carrying, levitating and translating matter in a contactless manner.

An acoustic-wave generating device includes a drive circuit and a power auxiliary circuit. The drive circuit includes a capacitor chargeable via a direct-current power supply, and a drive switch to cause power to be supplied from the capacitor to an acoustic-wave source which produces heat through energization to generate acoustic waves. The power auxiliary circuit is operable to supplies power to the drive circuit to avoid a decrease of power supplied to the acoustic-wave source in an operation of generating a series of acoustic waves from the acoustic-wave source through switching of the drive switch.

A method of determining a resonance frequency of a capacitive micromachined ultrasound transducer may include directing a broadband excitation waveform at an ultrasound transducer, wherein the excitation waveform comprises a frequency band which includes an anticipated resonance frequency of the ultrasound transducer; and measuring a ringdown characteristic of the ultrasound transducer.

A hybrid shaker system comprises two subsystems: a hydraulic shaker that generates vibrational movement mainly in a low frequency range, and an electrodynamic (ED) shaker that generates vibrations mainly in a high frequency range, with both contributing within a transitional intermediate frequency range. The shaker subsystems are connected in series so that cylinder piston rods of the hydraulic system drive the ED shaker housing, which in turn vibrates a unit-under-test (UUT). A single integrated vibration controller controls both the servo system of the hydraulic system and the power amplifier of the ED shaker using comparison of a target vibration profile with sensor feedback from the ED shaker housing and UUT. Vibrational movement of the UUT over a complete frequency range up to a few thousand kilohertz can be covered, while providing very large displacements up to 25 centimeters during the same test.

A vibratory actuator includes a vibration body, a contact body, a base, a holding member, and a flexible substrate. The vibration body includes an elastic body and an electro-mechanical energy conversion element. The contact body is in contact with the elastic body and relatively moves with the vibration body due to vibration of the vibration body. One end of the flexible substrate is arranged along a first surface of the holding member and is folded back with respect to an end portion of the holding member toward a second surface of the holding member on a back side of the first surface, and an other end of the flexible substrate is supported by a portion of the base. The flexible substrate separates from the second surface to form a U-turn portion so that the one end and the other end of the flexible substrate are electrically connected.