A body dryer includes an airflow generator to generate a flow of air, an inlet to pass air from the surroundings to the airflow generator, an outlet to vent the air from the airflow generator, a body, and a movable bar, the bar supported by the body. A drive assembly is provided between the body and the bar, the bar movably driven relative to the body. A noise cancellation device is provided to cancel or reduce noise in at least one of the airflow generator and the drive assembly.

Systems and methods for the reduction of noise arising from the fluid mechanics of the aerodynamic interactions of the relative motion of solid elements with a fluid, generally air, by generating pressure fields at or close to the source of the aerodynamic noise, these pressure fields having amplitudes and frequencies equivalent to those of the noise fields to be reduced, but phases opposite thereto. These generated pressure fields globally cancel the effect of the noise fields and this affect is propagated into the far field. Use is made of planar electro-thermal transducers, transforming a periodically fluctuating heat flux generated by Joule AC heating into an acoustic wave. The frequency, amplitude and phase of the noise field may be detected by microphones positioned close to points of generation of the noise field, such that the cancellation is effective over the same region as the noise field propagates.

A body dryer includes an airflow generator to generate a flow of air, an inlet to pass air from the surroundings to the airflow generator, an outlet to vent the air from the airflow generator, a body, and a movable bar, the bar supported by the body. A drive assembly is provided between the body and the bar, the bar movably driven relative to the body. A noise cancellation device is provided to cancel or reduce noise in at least one of the airflow generator and the drive assembly.

In one embodiment, a computer-program product embodied in a non-transitory computer readable medium that is programmed for performing active vibration cancellation (AVC) in a moving vessel is provided. The computer-program product includes instructions to receive a first signal indicative of vibrations that are exhibited on at least one passenger in a cabin of the moving vessel and to determine a resonant frequency of the vibrations that are exhibited on the at least one passenger based on the first signal. The computer-program product further includes instructions to generate a first anti-wave signal based on the resonant frequency and to drive at least one haptic actuator that is positioned proximate to the at least one passenger in the cabin with the first anti-wave signal to minimize motion sickness for the at least one passenger caused by the vibrations that are exhibited on the at least one passenger in the vessel.

An earphone controlling method includes: acquiring a first sound signal through a bone conduction element of the earphone; determining whether the first sound signal includes a voice signal sent by a wearer of the earphone according to the first sound signal; and controlling the earphone to operate in a transparent transmission mode when the first sound signal includes the voice signal.

The present disclosure is directed to controlling, reducing, and/or altering sound generated by an aerial vehicle, such as an unmanned aerial vehicle (UAV), while the aerial vehicle is airborne. For example, one or more transducers, such as piezoelectric thin-film transducers, or carbon nanotube transducers may be applied or incorporated into or on the surface of propeller blades that are used to aerially navigate the aerial vehicle. As the propeller blade rotates and generates sound, the transducers may be activated to generate one or more anti-sounds that cancel, reduce, or otherwise modify the sound generated by the rotation of the propeller blade. The anti-sound combines with the sound and causes interference such that the combined, or net-effect, is an overall cancellation, reduction, or other modification of the sound.

Noise and vibration sensing includes generating with an acceleration sensor a sense signal representative of the acceleration that acts on the acceleration sensor, and processing the sense signal to provide a processed sense signal having an adjustable signal bandwidth and an adjustable signal dynamic. The signal bandwidth extends between a lowest frequency and a highest frequency of the sense signal, and the signal dynamic is the ratio between a maximum amplitude of the sense signal and an output noise floor generated by the acceleration sensor. Noise and vibration sensing further includes adjusting the signal bandwidth and the signal dynamic in accordance with a control signal so that the signal bandwidth increases when the signal dynamic decreases and vice versa.

A microphone system may include a measuring device that includes a plurality of sound elements and a semiconductor chip connected to the sound elements and receives a vibration signal and a noise signal from the outside to cancel the vibration signal and changes a phase of the noise signal to output a reverse phase noise signal; and a driver that is connected to the semiconductor chip and is included in a front glass of a vehicle and vibrates in response to the reverse phase noise signal to cancel a noise signal inputted from the outside.

An acoustic conversion device for an active noise control is provided. The acoustic conversion device can effectively suppress or remove noise by controlling variation in a lowest resonance frequency. A volume of a closed space is smaller than an equivalent compliance air volume of a speaker unit. Therefore, motion of a vibration plate, an edge and a damper is suppressed, it is possible to restrain the edge and the damper from being deteriorated with time, variation in lowest resonance frequency can be suppressed, phase of emitted sound can be less prone to be deviated from opposite phase of noise, and it is possible to effectively suppress or remove noise.

Noise and vibration sensing includes generating with an acceleration sensor a sense signal representative of the acceleration that acts on the acceleration sensor, and processing the sense signal to provide a processed sense signal having an adjustable signal bandwidth and an adjustable signal dynamic. The signal bandwidth extends between a lowest frequency and a highest frequency of the sense signal, and the signal dynamic is the ratio between a maximum amplitude of the sense signal and an output noise floor generated by the acceleration sensor. Noise and vibration sensing further includes adjusting the signal bandwidth and the signal dynamic in accordance with a control signal so that the signal bandwidth increases when the signal dynamic decreases and vice versa.