In one inventive concept, a method for etching an optic includes obtaining a microemulsion, where the microemulsion includes a continuous oil phase, a surfactant system comprising at least one surfactant, and water, submerging at least a portion of the optic in the microemulsion, and agitating by ultrasonication the microemulsion for etching the optic submerged therein.

An assembly is configured to be coupled to a propagating medium. The assembly includes a first conductive layer including a first set of parallel conductors, a second conductive layer including a second set of parallel conductors, and a piezoelectric material layer between the first conductive layer and the second conductive layer. Different piezoelectric transducer nodes are formed at intersections between the first set of parallel conductors and the second set of parallel conductors.

For a resonator system such as a (haptic) LRA, a methodology for resonant frequency (F0) tracking/control with continuous resonator drive, based on estimating back-emf, including estimating resonator resistance based at least in part on the sensed resonator drive signals, with back-emf estimated based at least in part on the sensed resonator drive signals and the estimated resonator resistance. A phase difference is detected between the resonator drive signals, and the estimated back-emf signals, generating control for resonator drive frequency, which can be used to iteratively adjust the resonator drive frequency until phase coherent with the estimated back-emf signals (F0 lock), such as for driving the resonator at or near a resonant frequency. An amplitude control loop can be used to iteratively adjust resonator drive amplitude based on a difference between estimated back-emf and a target back-emf derived from a rated back-emf and the resonator frequency resonant frequency.

A system includes sensor-actuator units fixed onto a plate to be actuated according to at least one predetermined vibratory mode, each sensor-actuator unit having an electromechanical actuator and a deformation or vibratory speed sensor, wherein the electromechanical actuator and the sensor are colocated on the surface, that is to say that the measurement by the sensor is performed in immediate proximity to the electromechanical actuator, this proximity being such that the actuator and the sensor can respectively actuate and measure the same predetermined vibratory mode.

The present disclosure provides an ultrasound transducer (UT) assembly for ultrasonic and photoacoustic dual-mode imaging of an endoscope, including a UT and a microlens integrated in the UT. The microlens is used for beam collimation or focusing and accommodated in an aperture of the UT. A probe/catheter including the UT assembly, an endoscopy system including the probe/catheter, and a method of manufacturing the UT assembly are also provided. The present application uses a photocurable glue and mold to form the microlens integrated in the UT and adopts the coaxial arrangement of the devices to solve the problems of light supply and device dimensions (rigid length and diameter), thereby simplifying the manufacturing process of intravascular photoacoustic (IVPA) probe/catheter.

Ultrasonic sensing approaches are described with integrated MEMS-CMOS implementations. Embodiments include ultrasonic sensor arrays for which PMUT structures of individual detector elements are at least partially integrated into the CMOS ASIC wafer. MEMS heating elements are integrated with the PMUT structures by integrating under the PMUT structures in the CMOS wafer and/or over the PMUT structures (e.g., in the protective layer). For example, embodiments can avoid wafer bonding and can reduce other post processing involved with conventional manufacturing of PMUT ultrasonic sensors, while also improving thermal response.

A vibration device is provided that includes a vibration element with a piezoelectric vibrator and a driving device that causes the vibration element to vibrate. The vibration element includes a translucent body and the piezoelectric vibrator is electrically coupled to the driving device. The driving device includes a first circuit that applies an electric signal to the piezoelectric vibrator to render the vibration element in a resonant state, a second circuit that applies an electric signal to the piezoelectric vibrator according to a feedback signal output from the piezoelectric vibrator, and a switch that switches coupling between the first circuit and the piezoelectric vibrator and coupling between the second circuit and the piezoelectric vibrator at a certain timing.

Described herein are apparatuses and methods for use therewith that can be used to remove dust and other types of particulates from a solar array of a spacecraft, a lander, a rover, or the like. Such an apparatus can include a main body and a solar array extending from the main body. One or more piezoelectric devices is/are attached to the solar array. The piezoelectric device(s), when activated, is/are configured to vibrate at least a portion of the solar array to thereby loosen particulates adhered thereto. The apparatus also includes one or more linear actuators that when actuated is/are configured to at least one of bump against, push on, or pull on at least a portion of the solar array to thereby jettison from the solar array at least some of the particulates that were loosened by the one or more piezoelectric devices.

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.