An ultrasonic transducer for a measuring instrument includes a housing container with a support plate and a piezoelectric element that is supported by the support plate and has a substantially circular shape. The piezoelectric element includes multiple substantially sector-shaped oscillation parts that are divided by multiple grooves that communicate with each other at the central part and extend radially. The piezoelectric element oscillates in the thickness direction A3 in the first frequency band and in the radial direction A4 in the second frequency band, which is lower than the first frequency band. The ultrasonic transducer is capable of expanding the frequency band suitable for transmitting and receiving ultrasound.

An acoustic transducer (30), comprising: a support structure (36); an active assembly comprising a base plate (32) supported by the support structure (36) and a piezoelectric body (34) supported by the base plate (32); and a passive vibrator (38) supported by the support structure (36) and coupled via the support structure (36) to the active assembly (32, 34) so that vibration of the active assembly (32, 34) drives the passive vibrator (38). The active assembly (32, 34) and the passive vibrator (38) have the same resonant frequency.

Hair cells are exquisitely sensitive to auditory stimuli, but also to damage from a variety of sources including noise trauma and ototoxic drugs. Mammals cannot regenerate cochlear hair cells, while non-mammalian vertebrates exhibit robust regenerative capacity. To allow for the effective examination of this process disclosed herein is a design and method of utilizing a device capable of inducing acoustic trauma in the larval lateral line. The device uses ultrasonic transducers to induce cavitation wherein microbubbles form in the fluid medium inside the container. These bubbles oscillate and then implode, sending shockwaves into the fluid inside the well-plate containing the fish. The device emits a broadband signal with peak sound energy in the low-frequency range below 200 Hz, consistent with the response range of the larval lateral line.

Techniques are disclosed for systems and methods to provide transmission signal shaping for transmission signal-based sensor systems, such as radar and/or sonar sensor systems. A low noise signal shaping transmitter includes a digital to analog converter configured to convert a digital shaping control signal to an analog shaping control signal, a signal shaping circuit configured to convert the analog shaping control signal into a shaped voltage, and a power amplifier configured to provide a shaped transmission signal based on the shaped voltage and a digital transmission control signal. Each element of the transmitter may be formed from relatively slow switching analog and/or digital circuitry components. Resulting shaped transmission signals may be used to excite radar antennas, sonar transducers, sound cells, and/or other elements of sensor systems.

A foundation pile end piece is provided that includes a ring-shape connection housing, where a proximal end of the ring-shape connection housing is configured to secure to a bottom end of a foundation pile, a moveable tip, where a distal end of the ring-shape connection housing is configured to fixedly hold the moveable tip, where the moveable tip is disposed to oscillate transversely with respect to a central axis of the ring-shape connection housing, where the moveable tip is configured to displace soil from the bottom end of the foundation pile according to actuation of the oscillation.

Techniques are disclosed for systems and methods to provide accurate and reliable compact sonar systems for mobile structures. A sonar system includes multiple sensor channels, each comprising a sonar transmitter and a sonar receiver, and a logic device configured to provide control signals and receive sensor signals from the sensor channels. The logic device is configured to provide transmission signals to sonar transducer assemblies, where signal patterns of the transmission signals are differentiated based at least in part on frequency content. Acoustic returns are processed using the signal patterns to reduce inter-channel pickup between the sensor channels. Resulting sonar data and/or imagery may be displayed to a user and/or used to adjust a steering actuator, a propulsion system thrust, and/or other operational systems of the mobile structure.

A transducer is provided, which includes an oscillator and a broadbanded matching circuit. In the oscillator, a peak frequency corresponding to a peak transmission sensitivity may separate from a center frequency in a given bandwidth, and a transmission sensitivity may increase as a frequency separates from the peak frequency with respect to the center frequency. The broadbanded matching circuit may be configured to perform an impedance matching so that the transmission sensitivity of the oscillator at the peak frequency becomes substantially equal to the transmission sensitivity of the oscillator at the center frequency.

Disclose displacement connectors of high bending stiffness, high-performance piezoelectric actuators and derivative devices made of such. The connector has circumferentially alternating recess housings which, when fitted with the intended piezoelectric active elements makes displacement actuators, approximately double (2), triple (3) or quadruple (4) the displacement of individual active elements without adversely jeopardizing their regenerative forces. The connector may take any overall cross-section and length to suit intended applications. Connector recesses can be configured to house piezoelectric elements of a wide variety of cross-sections and dimensions, including longitudinal mode stacks, transverse mode bars and/or tubes, single crystal blocks of suitable cut and dimensions and their bonded assemblages.

Provided is a fixture for concentrically aligning and assembling a Ceramic Stack Assembly transducer during manufacturing. The CSA fixture comprises a base, a top compression cap, a central rod and a fastener, one or more alignment posts, and a driving wedge. The base further includes a groove to accept and align a transducer rear-centering ring at a central axis of the fixture. The transducer rear-centering ring supports one or more copper foil or ceramic rings during assembly. The alignment posts and driving wedge apply radial pressure to the copper foil or ceramic rings during assembly to force concentric alignment. The top compression cap, central rod, and fastener compress and stress the CSA Ceramic once assembled. The fixture simultaneously provides concentric alignment, foil alignment and provides a mechanism for stressing the CSA. A method of use is also provided.

A system for producing sound waves in a medium, the system comprising: at least two first free-flooded ring transducers centered about a first axis, the first free-flooded ring transducers being substantially cylindrical and having an axial gap of height g therebetween such that they form a first column; and at least one cylindrical body centered about the first axis nested in the first column, such that the cylindrical body is aligned with the axial gap. The cylindrical body may be a tweeter free-flooded ring transducer. This provides for improved wideband performance in a free flooded ring array.