The present invention relates to a haptic feedback system and, particularly, to a device and a method for controlling an actuator for haptic feedback, the method comprising: a first step of controlling the output of an oscillator such that a clock necessary in the generation of a driving signal for driving an actuator is oscillated at a reference clock frequency; a second step of calculating the resonance frequency of the actuator from a cycle of a BEMF signal according to the driving of the actuator; and a third step of calculating a clock frequency for following the calculated resonance frequency of the actuator so as to newly change and set same to the reference clock frequency, thereby controlling the output of the oscillator.

Systems and methods resolve stresses in additive manufacturing. A stress resolution profile including frequency and amplitude parameters of an ultrasonic input are determined based on physical properties of the product. Successive layers of a material are added and energy is applied to incorporate the material of each layer into the product. An ultrasonic input is applied with the determined parameters to resolve stress as the product is built up. The ultrasonic input is varied as a depth of the material incorporated into the product increases.

An acoustic technique designed to increase the gas-dissolution rate of a bubble in a liquid media is proposed. Increased gas-dissolution rate is achieved by increasing the bubble's surface-to-volume ratio via bubble fragmentation. This is achieved by attaching an electroacoustic transducer to the system or load in which bubbles travel and exciting the transducer at the frequency of resonance. The electric resonance of the transducer attached to the system corresponds in frequency to the mechanical resonance of the system or load which allows for achieving such state without the use of an internally placed hydrophone to certify the resonance state. The acoustic bubble fragmentation technique increased the dissolution rate 4 to 5 times of bubbles with initial diameters between 150 and 550 μm in distilled water and in medical grade saline solution.

A resonance method for a vibration system for resonant vibration of an excitation unit having a vibrating mass includes detecting a deflection of the vibrating mass, differentiating the deflection to form a velocity of the vibrating mass; generating from the deflection and the velocity a mechanical phase position; forming from the mechanical phase position a corrected phase position by using a correction value; forming, based on the corrected phase position, an electrical angular frequency with a P-regulation; integrating the electrical angular frequency to determine an electrical phase position; forming from the electrical phase position a correction factor by using a trigonometric function; and applying the correction factor to an excitation setpoint value to generate a corrected excitation setpoint value. Also disclosed are a converter, an excitation unit having the converter, and a vibration system having the excitation unit and the vibrating mass.

Prior to manufacturing a product by additive manufacturing, a stress relief profile including frequency and amplitude parameters of an ultrasonic input is determined based on physical properties of the product, including resonant frequencies of the product and a material from which the product is manufactured. Successive layers of a material are added and energy is applied to incorporate the material of each layer into the product. A processor accesses stress relief profile parameters for each layer, determines whether a layer requires stress relief and determines a frequency and a power level for the stress relief at the layer. An ultrasonic input is applied with the determined parameters to relieve stress as the product is built up.

A non-Hermitian complementary metamaterial (NHCMM). Acoustic transmission systems including an acoustic wave generator configured to generate an acoustic wave and propagate the acoustic wave through a tissue of a specimen, and the NHCMM, which is configured to add a first amount of energy amplification coherently to the acoustic wave to account for energy loss in the acoustic wave as a result of the wave propagating through the tissue of the specimen. The acoustic wave generator can be an ultrasound generator, and the tissue can be a cranium.

The disclosure relates to the field of spray welding, and involves a method and a device for liquid spray welding, as well as the application method thereof. The method for liquid spray welding specifically comprises the following steps: S1: Solder to be spray-soldered is melted under the protection of an inert gas; S2: Then, the melted solder is spray-soldered while using ultrasonic focusing. The device includes a solder conversion mechanism which consists of a container; the cavity in the container is used for placing the solder; a spraying hole is arranged at the bottom of the container to connect with the cavity, and a heating mechanism is mounted along the outer wall of the container; a device for driving the solder spraying is used to control the frequency of an ultrasonic generating mechanism.

A control console for a powered surgical tool. The console includes a transformer that supplies the drive signal to the surgical tool. A linear amplifier with active resistors selectively ties the ends of the transformer primary winding between ground and the open circuit state. Feedback voltages from the transformer windings regulate the resistances of the active resistors.

An electronic apparatus to which an external apparatus is detachably attachable includes a controlling unit configured to make a vibration device vibrate by using a vibration parameter corresponding to a type of the external apparatus to be attached to the electronic apparatus, the vibration device being provided on at least one of the electronic apparatus and the external apparatus.

Amplifier architecture that allows low-cost class-D audio amplifiers to be compatible with ultrasonic signals, as well as loads presented by thin-film ultrasonic transducers. The amplifier architecture replaces the traditional capacitor used as an output filter in the class-D amplifier with the natural capacitance of the ultrasonic transducer load, and employs relative impedance magnitudes to create an under-damped low-pass filter that boosts voltage in the ultrasonic frequency band of interest. The amplifier architecture includes a secondary feedback loop to ensure that correct output voltage levels are provided.