Abstract: A modular actuator assembly includes one or more plates or elements of electro-active material bonded to an electroded sheet, preferably by a structural polymer to form a card. The card is sealed, and may itself constitute a practical device, such as a vane, shaker, stirrer, lever, pusher or sonicator for direct contact with a solid or immersion in a fluid, or may be bonded by a stiff adhesive to make a surface-to-surface mechanical coupling with a solid workpiece, device, substrate machine or sample. The structural polymer provides a bending stiffness such that the thin plate does not deform to its breaking point, and a mechanical stiffness such that shear forces are efficiently coupled from the plate to the workpiece. In further embodiments, the card may include active circuit elements for switching, powering or processing signals, and/or passive circuit elements for filtering, matching or damping signals, so that few or no connections to outside circuitry are required.

Abstract: A modular actuator assembly includes one or more plates or elements of electro-active material bonded to an electroded sheet, preferably by a structural polymer to form a card. The card is sealed, and may itself constitute a practical device, such as a vane, shaker, stirrer, lever, pusher or sonicator for direct contact with a solid or immersion in a fluid, or may be bonded by a stiff adhesive to make a surface-to-surface mechanical coupling with a solid workpiece, device, substrate machine or sample. The structural polymer provides a bending stiffness such that the thin plate does not deform to its breaking point, and a mechanical stiffness such that shear forces are efficiently coupled from the plate to the workpiece. In further embodiments, the card may include active circuit elements for switching, powering or processing signals, and/or passive circuit elements for filtering, matching or damping signals, so that few or no connections to outside circuitry are required.

Abstract: The metal-ceramic actuator includes an electroactive substrate having at least a pair of opposed planar surfaces and a determined thickness, with the ceramic substrate being poled in its thickness dimension. Conductive electrodes sandwich the ceramic substrate and are bonded to its planar surfaces. Metal caps, each having a concave cavity bounded by a rim, are bonded to both planar surfaces of the ceramic substrate. A potential is applied to the conductive electrodes to cause an expansion of the ceramic substrate in its thickness dimension and a concomitant contraction in its planar dimensions. The contraction creates a flexure of the metal caps, which flexures are used to actuate another instrumentality.

Abstract: This invention describes an acoustic transducer assembly wherein an extremely high figure of merit (d.sub.h g.sub.h) is obtained as a result of converting incoming acoustic axial stress into radial extensional stress thereby multiplying its effect. The piezoelectric active element is encased in a metal sandwich enclosing two semilunar air spaces which allow the device to withstand extremely high hydrostatic pressure yet still respond to low level sound waves when acting as a hydrophone. The mechanical prestress induced by the differential coefficients of expansion between the metal case and the piezoelectric ceramic element also serves to prevent depolarization aging.