Sensors may incorporate ultrasonic cleaning device controllers and methods to keep their exposed surfaces free from water, ice, and other adherent substances. One illustrative controller includes a driver configured to drive a transducer with a periodic waveform having voltage pulses and high impedance intervals repeating at a drive frequency. The controller may also include a receiver configured to measure a high impedance voltage of the transducer during the high impedance intervals. The controller may further include control logic configured to adjust the drive frequency using the high impedance voltage to track a resonance frequency of the transducer. Some implementations may use diagnostic bursts with lower voltage pulse magnitudes for tracking and cleaning bursts with higher voltage pulse magnitudes for cleaning. Duty cycle fading may be employed to prevent voltage overshoots after each burst.

A vibration device that includes: a vibration body; a piezoelectric element at a first end of the vibration body in a first direction; and a translucent body that has an optical axis extending in the first direction and at a second end of the vibration body in the first direction. The vibration body includes a first flange portion connected to the translucent body, a second flange portion connected to the piezoelectric element, and an arm portion that connects the first flange portion to the second flange portion. In a cross-section including the optical axis, the first flange portion and the second flange portion extend from a position separate from the optical axis in a second direction intersecting the first direction in a direction towards to the optical axis. The arm portion has a curved shape in the cross-section including the optical axis.

The subject matter of this specification can be embodied in, among other things, a sensor that includes a first axial sensor housing portion having a first cross-sectional area, a second axial sensor housing portion arranged adjacent to the first axial sensor housing portion along the sensor axis and having a second cross-sectional area larger than the first cross-sectional area, and a face extending from the interior surface of the first axial sensor housing portion to the interior surface of the second axial sensor housing portion, a first buffer rod within the first axial sensor housing portion and having a first axial end and a second axial end, a second buffer rod within the second axial sensor housing portion and abutting the face, and having a third axial end and a fourth axial end, and an acoustic transceiver element acoustically mated to the second axial end and the third axial end.

A vibrator structure of an aerosol generating device is provided. The vibrator structure includes a vibrator configured to vibrate according to an electrical energy applied to the vibrator, the vibrator including a first surface and a second surface opposite to the first surface; a first electrode arranged on at least one region of the first surface; a second electrode arranged on at least one region of the second surface; and a metal body accommodating the vibrator and being in contact with at least one region of the first electrode, wherein the electrical energy applied from an external power source is transferred to the first electrode through the metal body.

Disclosed are a dry-coupling ultrasonic transducer that can deliver either focused and non-focused ultrasound to the brain without the use of hydrogel or degassed water as coupling media, while minimizing acoustic distortion, and a wide-area transcranial ultrasound sonication device that incorporates the ultrasonic transducer. The ultrasonic transducer includes a main body configured to generate ultrasound and a dry acoustic coupler configured to transmit the ultrasound to a sonication target, wherein the coupler includes a plurality of flexible coupling pins extending from the front surface of the transducer main body, to provide direct contact with the sonication target.

A system comprises a support, typically part of dishwashing machine or clothes washing machine, having a plurality of piezoelectric transducers. Each transducer can have a cylindrical housing with a water inlet along a side surface of the housing. The transducers can also comprise a lens and a piezoelectric material with electrodes configured to couple to a power supply.