An aerosol generating device includes a vibrator configured to vibrate to generate an aerosol from an aerosol generating material, a controller configured to control the vibrator to vibrate at a target vibration speed, and a feedback circuit configured to detect an electrical signal representing a frequency response of the vibrator that changes according to an operating environment of the vibrator and output a feedback signal based on the detected electrical signal, and the controller may adjust the vibration speed of the vibrator based on the feedback signal output from the feedback circuit.

An ultrasonic apparatus includes an ultrasonic transducer, a transmitting circuit, a receiving circuit, a Q-factor measuring circuit, and a frequency measuring circuit. The ultrasonic transducer is a three-terminal ultrasonic transducer that includes a transmitting electrode, a receiving electrode, and a common electrode. The transmitting circuit outputs a driving signal to the transmitting electrode to cause the ultrasonic transducer to transmit ultrasonic waves. The receiving circuit receives a receive signal from the receiving electrode. The frequency measuring circuit measures a resonant frequency of the ultrasonic transducer from a reverberation signal in the receive signal. The Q-factor measuring circuit measures a Q factor of the ultrasonic transducer from the reverberation signal in the receive signal.

A controller for a haptic actuator is described. The controller includes a driver which has an output configured to be coupled to a linear resonant actuator in a first mode and a frequency detector having an input configured to be coupled to the haptic actuator in a second mode. The frequency detector is configured to detect a signal generated on the terminals of the haptic actuator in response to an externally applied force and to determine a resonant frequency of the haptic actuator from the generated signal.

A vibration control device, while applying Gaussian vibration that matches a target vibration physical quantity PSD to a test piece, makes a corresponding vibration physical quantity non-Gaussian. Using a response vibration physical quantity PSD and a target vibration physical quantity PSD, a control vibration physical quantity PSD calculation generates a control vibration physical quantity PSD for generating a drive signal. A PSD conversion converts the control vibration physical quantity PSD into a control corresponding vibration physical quantity PSD of another dimension. Using the control corresponding vibration physical quantity PSD, a control corresponding vibration physical quantity waveform calculation calculates a control corresponding vibration physical quantity waveform that is non-Gaussian. At least based on the control characteristics and the control corresponding vibration physical quantity waveform, a drive waveform calculation generates a next drive waveform such that vibration that matches the control corresponding vibration physical quantity waveform is applied to a test piece.

Systems and methods for non-invasive fat reduction can include targeting a region of interest below a surface of skin, which contains fat and delivering ultrasound energy to the region of interest. The ultrasound energy generates a thermal lesion with said ultrasound energy on a fat cell. The lesion can create an opening in the surface of the fat cell, which allows the draining of a fluid out of the fat cell and through the opening. In addition, by applying ultrasound energy to fat cells to increase the temperature to between 43 degrees and 49 degrees, cell apoptosis can be realized, thereby resulting in reduction of fat.

A method for controlling at least two mechanical oscillators, more particularly in a motor vehicle, where each oscillator oscillates at a frequency during operation and where the frequency can be controlled by the power applied to the oscillators, includes arranging a single sound transducer at a distance from the oscillators and capturing an electrical signal, where the electrical signal is subjected to a Fourier transform and thus a Fourier spectrum is determined. The frequency of each oscillator is determined from extreme values of the Fourier spectrum.

Embodiments described herein relate to methods and apparatus for driving a haptic transducer with a driving signal. The method comprises estimating, based on a current through the haptic transducer and a terminal voltage across the haptic transducer, a back electromotive force, EMF, voltage representative of a velocity of a mass in the haptic transducer; comparing a phase of a voltage signal derived from the terminal voltage with a phase of the estimated back EMF voltage; and based on the comparison, adjusting a frequency or a phase of an output signal, wherein the driving signal is derived from the output signal, such that a frequency of the driving signal converges to a resonant frequency of the haptic transducer.

A hookah device (202) which attaches to a hookah (246). The hookah device (202) comprises a plurality of ultrasonic mist generator devices (201) for generating a mist for inhalation by a user. The hookah device (202) comprises a driver device (202) which controls the mist generator devices (201) to maximize the efficiency of mist generation by the mist generator devices (201) and optimize mist output from the hookah device (202).

An acoustophoretic system is controlled and driven to attain a desired level of performance. An RF controller and a driver provide a frequency and power to an acoustic transducer, which can be implemented as a piezoelectric element, which presents a reactive load or a complex load. A controller implements a control technique for efficient transducer operation. The control technique can locate a frequency for operation that is at a reactance minimum or maximum for the system to produce a modal pattern and to provide efficient operation of the transducer. A method of detecting a minimum or maximum reactance in a acoustophoretic system used to trap, separate, deflect, cluster, fractionate or otherwise process particles or secondary fluids or tertiary fluids in a primary fluid and utilizing the frequency of the detected reactance to operate the acoustophoretic system.

A method and an apparatus to improve the precision and reproducibility of particle size analysis by laser diffraction is presented. Powder particles are typically prepared for laser diffraction testing using an ultra-sound bath which will disperse particle agglomerates and allow a precise measurement. However, the precision and reproducibility of agglomerate dispersion is affected by ultra-sound probe wear, corrosion and age. Differences in sonication performance can be compensated by voltage adjustments to the ultra-sound probe, leading to substantial improvements in the precision and reproducibility of particle size determination.