Abstract: A method and apparatus for mechanical strain amplification for enhanced piezoelectric transduction. The device consists of a piezoelectric element elevated above the neutral axis of a supporting, micromachined, photoetched substrate by use of castellations on the substrate. By elevating the piezoelectric element above the neutral axis, the charge sensitivity of the device is increased which facilitates the development of high-sensitivity, low-noise transducers. There is a limit to charge sensitivity because the optimal elevation is a function of the physical properties of the supporting structure and the piezoelectric element. Accordingly, a mathematical formulation and finite element analysis (FEA) are provided to define the optimal height of the castellated substrate. The recognition of limits to the castellation height has further led to the discovery of using the relaxor-ferroelectric, single crystal class of materials in the present invention.

Abstract: A motion device with three legs provides six degrees of freedom using a pair of motor assemblies (22) to drive each leg. Each leg has a differential drive (28, 30, 32, 40) for providing a pitch-roll joint connected to an elbow (16) for providing a pitch joint connected to a second roll joint (56) connected to a universal joint (62, 72). An actuated plate (10) is connected to the universal joint. All of the motors drive the differential drive from the base of the unit and do not add inertia to the actuated plate. The same kinematic arrangement can be used for hand controllers as well as for end effectors and other movable platforms.