An hourglass transducer including a longitudinal driver, a shell, and a pair of endcaps is provided. The driver drives the transducer. The pair of endcaps is attached to ends of the driver and cap the shell enclosing the transducer. The shell includes a first shell end, a second shell end, and a pleated geometry. The first shell end and second shell end are structured with circular cross sections. The pleated geometry is between the first shell end and the second shell end. A perimeter of the pleated geometry is the same as perimeters of the circular cross sections of the first shell end and the second shell end.

An underwater acoustic transducer that is capable of radiating acoustic energy at low frequencies. A transducer which is a resonant low frequency bender-type transducer driven at its end supports by a piezoelectric stack of material operating with inner and outer parts driven in opposite directions creating a bending motion of a radiating beam, plate or disc. The small piezoelectric motions at the beam supports are magnified by the leveraged motion of the bending beam(s) creating significant output at low frequencies.

A diaphragm for a piezoelectric micromachined ultrasonic transducer (PMUT) is presented having resonance frequency and bandwidth characteristics which are decoupled from one another into independent variables. Portions of at least the piezoelectric material layer and backside electrode layer are removed in a selected pattern to form structures, such as ribs, in the diaphragm which retains stiffness while reducing overall mass. The patterned structure can be formed by additive, or subtractive, fabrication processes.

Embodiments related to marine acoustic vibrator for marine geophysical surveys. An embodiment may include an apparatus, wherein the apparatus may comprise: a coil element comprising a coil; a coil clamp constraining motion of the coil element in at least one direction; and a spring disposed in a load path of the coil clamp. Additional apparatus and methods are disclosed herein.

An air pulse generating element is disclosed. The air pulse generating element includes a front faceplate; a back faceplate; a front supporting element; a back supporting element; a folded membrane, configured to form a front chamber and a back chamber, and comprising a plurality of membrane units; wherein the plurality of membrane units are parallel and sequentially connected and an end of the folded membrane is connected to the back faceplate via the back supporting element and another end of the folded membrane is connected to the front faceplate via the front supporting element; and a plurality of valves controlling a plurality of air flow channels between the front chamber toward either a front space or a back space; wherein the plurality of membrane units are configured to perform horizontal deformation to squeeze air in and out of the front or back chamber with operations of the plurality of valves.

A haptic actuator assembly includes a haptic actuator configured to output displacement along a perpendicular axis and a pre-load device. The pre-load device is disposed adjacent to the haptic actuator and configured to generate a compressive load on the haptic actuator along the perpendicular axis to oppose expansion of the haptic actuator along the perpendicular axis. The haptic actuator is disposed within an enclosed cavity formed by a casing. A pressure within the enclosed cavity is varied in order to create the compressive load on the haptic actuator along the perpendicular axis. The pre-load device may alternatively be a connector component formed from a shrinkable material that is configured to longitudinally shrink to exert a force in order to create the compressive load on the haptic actuator along the perpendicular axis.

Embodiments relate to marine seismic vibrators and associated methods of use. An embodiment provides a marine seismic vibrator comprising: a shell comprising endbeams and shell side portions coupled to the endbeams, wherein each of the shell side portions has a midline between the endbeams, wherein each of the shell side portions has a thinner portion at the midline to force each of the shell side portions to bend at the midline; a driver disposed within the shell; and a pair of spring elements disposed within the shell on either side of the driver, wherein the pair of spring elements are coupled to the driver and to the shell such that movement of the driver is transferred to the shell by way of the spring elements, wherein the pair of spring elements have a second mode of oscillation that provides a second resonance frequency within the operational frequency range.

A diaphragm for a piezoelectric micromachined ultrasonic transducer (PMUT) is presented having resonance frequency and bandwidth characteristics which are decoupled from one another into independent variables. Portions of at least the piezoelectric material layer and backside electrode layer are removed in a selected pattern to form structures, such as ribs, in the diaphragm which retains stiffness while reducing overall mass. The patterned structure can be formed by additive, or subtractive, fabrication processes.

A haptic actuator assembly includes a haptic actuator configured to output displacement along a perpendicular axis and a pre-load device. The pre-load device is disposed adjacent to the haptic actuator and configured to generate a compressive load on the haptic actuator along the perpendicular axis to oppose expansion of the haptic actuator along the perpendicular axis. The haptic actuator is disposed within an enclosed cavity formed by a casing. A pressure within the enclosed cavity is varied in order to create the compressive load on the haptic actuator along the perpendicular axis. The pre-load device may alternatively be a connector component formed from a shrinkable material that is configured to longitudinally shrink to exert a force in order to create the compressive load on the haptic actuator along the perpendicular axis.

A linear transducer is connected to a first flexible member that has a first elongated shape with a first minor axis and a first major axis perpendicular to each other. This connects the linear transducer to opposite portions of the first flexible member along the first major axis. A second flexible member having an elongated shape with a second minor axis and a second major axis is provided. The second flexible member is connected to the first flexible member such that portions on the second major axis are joined to move with portions of the first flexible member on the first minor axis. Operation of the linear transducer multiplies displacements of the second flexible member relative to those of the transducer.