Abstract: An apparatus is provided including at least one electronic component. The apparatus also includes an enclosure enclosing the at least one electronic component. The enclosure includes at least one wall defined by a membrane. The apparatus further includes a piezoelectric actuator that is fixed at a first end and rigidly attached to the membrane at a second end. Application of alternating current to the piezoelectric actuator generates a pulsating mechanical deformation of the membrane.

Abstract: A piezoelectric or electrostrictive composite exhibiting anisotropic 3-3 connectivity with a dense ceramic phase and an infiltrate polymer phase. The ceramic phase is an interconnected ceramic lamelli structure that is arranged substantially parallel in one direction. The ceramic lamelli have greater connectivity in the z direction than in the x and y directions, while the connectivity in the x and y directions are essentially equal.

Abstract: A seam-tracking apparatus for a welding system has a welding arm which directs an energy beam toward a seam. The seam-tracking apparatus includes an eddy current sensor formed by an array of eddy current elements, each producing a respective electrical signal when positioned adjacent to the seam to be tracked. An eddy current signal processor receives each respective electrical signal so as to generate position data indicative of the location of the seam. A controller is responsive to the position data so as to align the eddy current sensor and the welding arm over the seam so that the energy beam continuously impinges on the seam, as the welding arm advances along the seam. The eddy current sensor may be flexible, in which case the seam-tracking apparatus can track a seam between workpieces having curved surfaces.