A vibrotactile device including a first actuator channel having a vibrotactile actuator and a resistor with a predetermined resistance positioned at an input of the vibrotactile actuator, a processor configured to output a driving signal for driving the vibrotactile actuator, and a voltage sensor configured to measure a voltage drop across the resistor. A current drawn by the vibrotactile actuator varies according to a load applied to the vibrotactile actuator and passes through the resistor. The processor is configured to receive voltage drop measurement data from the voltage sensor, detect a load applied to the vibrotactile actuator based on the measured voltage drop, and control the driving signal based on the detected load.

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).

Provided is a method for determining an operating range of an ultrasonic vibrating unit (7), which ultrasonic vibrating unit (7) is supplied with electrical power by a generator (2) via an output (2a) and is excited to vibrate ultrasonically, wherein at least constituent parts of the ultrasonic vibrating unit (7), preferably an ultrasonic transducer (8) contained therein, and constituent parts of the generator (2), preferably a matching network (2b) on the output side, form a tuned circuit (2c, 2d). The method is characterized in that a measuring circuit (3) is connected upstream of the output (2a) of the generator (2), via the measuring circuit (3), a voltage (U) is applied to the tuned circuit, and by the measuring circuit (3), at least the phase, preferably magnitude and phase, of an impedance of the tuned circuit are measured, and at least the phase, preferably the phase and magnitude, of the impedance are evaluated in order to determine the working range. The invention further relates to a circuit arrangement for carrying out the aforementioned method.

A gyro sensor includes a vibrator and a drive circuit. A PWM drive signal is applied to a pair of electrodes of the vibrator. The drive circuit outputs a high level signal and a low level signal to the electrodes as the PWM drive signal. The high level signal and the low level signal have potentials higher and lower than that of the reference signal, respectively. The drive circuit outputs the high level signal to one of the pair of electrodes and the low level signal to the other of the pair of electrodes.

A system and method for driving ultrasonic transducers and improvements to a phase track controller for reducing loss of lock occurrence is disclosed and described.

Embodiments of the invention provide a synchronous statically indeterminate mesh-beam excitation large-scale vibrating screen, including a screen box, a support spring group, a spring base, a motor mount, a tire coupling, and a motor, wherein, a statically indeterminate mesh-beam excitation body is arranged on the screen box, and the statically indeterminate mesh-beam excitation body has at least one synchronous eccentric block vibration exciter group and two self-synchronous eccentric block vibration exciter groups in it; each self-synchronous eccentric block vibration exciter group includes a self-synchronous transmission shaft fixed to the side plates of the screen box via a bearing chock, and self-synchronous eccentric blocks fixed to the side plates of the screen box in symmetry are arranged on the self-synchronous transmission shaft; the self-synchronous transmission shaft of the self-synchronous eccentric block vibration exciter group at the side of the motor is connected with a reducer via the tire coupling, and the reducer is connected to the motor via a transmission belt.

A system for generating acoustic ultrasonic vibration, with a generator for generating an alternating voltage (U) with a frequency f and converter for converting the alternating voltage into acoustic ultrasonic vibration, with a control device, which captures the vibration amplitude (A.sub.ist) of the ultrasonic vibration and compares said vibration amplitude with a desired vibration amplitude (A.sub.soil) and changes a manipulated variable with the goal of bringing the captured vibration amplitude (A.sub.ist) closer to the desired vibration amplitude (A.sub.soil). The generator has a frequency control module with a frequency control input. The frequency control module defines, in accordance with a signal present at the frequency control input, the frequency (f) of the alternating voltage (U) to be generated. A system which at least mitigates the mentioned disadvantages, allows higher processing speeds and associated abrupt load changes. A control apparatus converts an input signal into a manipulated signal, the desired vibration amplitude (A.sub.soil) being provided as the input signal, and the manipulated signal being connected to the frequency control input.

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.

A robotic cleaning appliance includes a housing to which is coupled a surface treatment item and a sensor assembly with first and second transducers and an acoustic interface. The first sonic transducer transmits sonic signals through an acoustic interface and out of a first acoustic opening toward a surface beneath the robotic cleaning appliance. The sonic signals reflect from the surface as corresponding returned signals received by the second sonic transducer via a second acoustic opening port of the acoustic interface. A first annular ring is defined around the first acoustic opening port and a second annular rings is defined around the second acoustic opening port. The annular ring attenuate direct path echoes between the acoustic opening ports. The first and second acoustic opening ports are coupled the first and sonic transducers, respectively, via first and second horns; and the horns are tilted from orthogonal with the surface.

An ultrasonic atomizer and a working state determining method are provided. The ultrasonic atomizer includes a liquid storage cavity, an ultrasonic atomization sheet, a controller, a control circuit, and a power supply. The control circuit includes: a first switch branch, being turned on or turned off in response to a first pulse signal outputted by the controller; a first boost branch. boosting an output voltage of the power supply in response to the turning-on or the turning-off of the first switch branch, to output a first drive signal for driving the ultrasonic atomization sheet; and an energy storage branch, storing energy in response to the first drive signal, and outputting a first detection voltage to the controller, to enable the controller to determine a current working state of the ultrasonic atomizer based on the first detection voltage.