Abstract: A tri-axial vibration isolation device having: a passive isolation assembly including a first frame, a plurality of passive lateral isolators supporting the support frame on the base, and a plurality of passive vertical isolators; and an actuator assembly including a second frame, a vertical actuator arranged between the load and the second frame, and a plurality of lateral actuators arranged between the second frame and the passive vertical isolators. The actuators can be piezoelectric elements that change their thickness in response to an electrical signal. The lateral actuators are arranged in oppositely poled pairs. An accelerometer or other sensor provides information to a controller that controls the actuators.

Abstract: A thin, lightweight electroacoustic actuator device covering a large surface area providing a high piston-like output over the frequency range of from at least 30 to in excess of 500 Hz comprising a stiff, lightweight face plate; a backing structure disposed below the face plate; at least one driver structure disposed between the face plate and the backing structure; and flexible structure flexibly connecting the at least one driver to the face plate.

Abstract: A thin, lightweight electroacoustic actuator device covering a large surface area providing a high piston-like output over the frequency range of from at least 30 to in excess of 500 Hz comprising a stiff, lightweight face plate; a backing structure disposed below the face plate; at least one driver structure disposed between the face plate and the backing structure; and flexible structure flexibly connecting the at least one driver to the face plate.

Abstract: A monolithic piezoelectric accelerometer of the longitudinal type having a ass element, a piezoelectric accelerometer sensor element and electrodes interconnecting the mass and sensor elements, in which the mass and sensor elements are formed as a monolithic structure. Included is the method for making the monolithic piezoelectric accelerometer.