Abstract:
Active noise control systems, devices, and methods are disclosed herein. Anti-snoring systems can include a first pillow unit having at least one error microphone and at least one speaker, at least one reference microphone configured to capture sound produced proximate to the at least one reference microphone, and a control unit operatively coupled to the first pillow unit and the at least one reference microphone. In some aspects, the control unit can be configured to produce an anti-noise in the at least one speaker disposed in the first pillow unit by processing signals received from the at least one error microphone and the at least one reference microphone using gated dynamic adjustments such that the anti-noise cancels any sound produced proximate the at least one reference.
Abstract:
Metrology tools are provided, which comprise both active and passive vibration isolation devices, passive or active isolation systems such as constrained layer dampers, particle impact dampers or liquid impact dampers, and/or noise cancellation transducers, combined in different supporting structures of the metrology tool to dampen and reduce vibrations at a wide range of frequencies and intensities, and to which frequency range spectral analysis and optimization may be applied to determine specific tool configurations according to the provided principles.
Abstract:
A system includes a mobile phone configured to create an inverted signal having characteristics inverse to identified noise components of a detected audio signal. The mobile phone is configured to provide the inverted signal as an output to a headphone, such that a combination of the identified noise components and the inverted signal substantially cancel each other out.
Abstract:
A system comprises a plurality of storage drives coupled to logic. The logic implements a noise-reducing feature selected from a group consisting of a first feature that limits system performance based on a level of ambient noise, a second feature that staggers access transactions among said storage drives, a third feature that staggers spin up among the storage drives, a fourth feature that at least partially cancels noise generated by the system, a fifth feature that limits fan speed, and combinations thereof.
Abstract:
The invention is directed to a system and method for noise cancellation for an apparatus such as an electric motors or generator. The system may comprise a plurality of actuators, a plurality of phase controllers, each phase controller receiving an input signal representing a movement of an apparatus and outputting an output signal based on the input signal and at least one predetermined phase shift, and a plurality of amplifiers, each amplifier receiving an output signal from one of the phase controllers and outputting an amplified signal to drive one of the actuators. The method may comprise the steps of generating a first signal representing a movement of the apparatus, generating at least one second signal based on (a) the first signal, (b) at least one predetermined phase shift, and (c) at least one predetermined amplitude, and driving at least one actuator with the at least one second signal.
Abstract:
Apparatus for reducing a vibration that is propagated from outside a structure involves using a stiffener having a support point and a base point situated a distance from the support point to absorb the vibration. When an outside vibration is propagated to the structure, elastic strains occur both in the structure and in the stiffener, and the support point moves relative to the base point. The vibration reduction apparatus monitors the relative velocity of the support point relative to the base point, and when the monitored relative velocity changes its direction, releases a coupling between the support point of the stiffener and the structure, resulting in quick release of potential energy induced by the elastic strain stored in the stiffener and zeroing of the relative velocity between the support point and the base point. The support point of the stiffener is immediately re-coupled to the main structure upon zeroing of the relative velocity, and the relative velocity continues to be monitored until it either becomes zero or again changes direction, at which time the coupling and recoupling is repeated.
Abstract:
A method and system are provided for reducing flow-induced resonance in a structure's cavity. A time-varying disturbance is introduced into the flow along a leading edge of the cavity. The time-varying disturbance can be periodic and can have the same or different frequency of the natural resonant frequency of the cavity. In one embodiment of the system, flaps are mounted flush with the surface of the structure along the cavity's leading edge. A piezoelectric actuator is coupled to each flap and causes a portion of each flap to oscillate into and out of the flow in accordance with the time-varying function. Resonance reduction can be achieved with both open-loop and closed-loop configurations of the system.
Abstract:
Sleep apnea screening and/or detection apparatus for use by a patient breathing through the nose and/or mouth and producing an air flow into and out of the lungs of the patient and creating audible sounds. It is comprised of a first microphone positioned in the vicinity of the patient's nose and mouth and out of contact therewith to pick up audible sounds created by breathing of the patient and providing a first electrical analog signal. A second microphone is provided which is positioned near the patient for picking up ambient noise in the vicinity of the patient and providing a second electrical analog signal, an active noise controller is provided for combining the first and second electrical analog signals to provide a third electrical signal for generating a fourth electrical signal providing a waveform which is closely correlated with the air flow of the patient. A classifier is provided for classifying the electrical waveform provided by the fourth electrical signal to determine when a disordered breathing event has occurred.
Abstract:
An active noise control system is provided for cancellation of noise in a duct. A speaker is mounted over an opening in the duct. An enclosure is mounted the duct about the speaker. Air flow is generated through the enclosure in order to balance the diffusion of water vapor through the speaker such that the dew point of the air in the enclosure is always below the temperature of the air in the enclosure, thus avoiding condensation.
Abstract:
An adaptive snoring signal suppression system globally cancels snoring signals by determining a canceling signal based on a received snoring signal. The system creates a doublet between a plane of a speaker and the source of the snoring signal such that at the plane of the speaker, the canceling signal is 180 degrees out of phase with the snoring signal as measured at the source. The system uses digital signal processing to adaptively estimate a snoring sound canceling signal based on past snoring signals.