Abstract: A piezoelectric drive motor especially well adapted for use with flow control systems on commercial aircraft, military aircraft and spacecraft. In one embodiment, the apparatus includes a support structure that supports a piezoelectric beam. A biasing element, for example a coil spring, is coupled between a free end of the piezoelectric beam and the support structure. The spring exerts a compressive force on the beam and serves to amplify its displacement when electric signals applied to piezoelectric layers on the beam cause deflection of the beam between two stable positions. The drive motor operates over a wider band of drive frequencies than conventional piezoelectric beams and is also suitable for use as a sensor and in a wide variety of actuator applications.

Abstract: An apparatus for use in low frequency vibration energy harvesting (VEH) and with actuators requiring a low deflection force. The apparatus includes a piezo flexure that is loaded with a compressive pre-load force to place the piezo flexure under compression. The piezo flexure may be supported at an intermediate point or at one end thereof. The compressive pre-load force produces flexes the piezo flexure into one or the other of two stable positions, these positions being offset on opposite sides of a longitudinal centerline representing the position of the piezo flexure that would be produced without the compressive pre-load force applied thereto. The compressive pre-load effectively provides a negative spring constant which “softens” the piezo flexure and enhances a responsiveness of the piezo flexure to low frequency vibration energy. The piezo flexure also operates over a much wider frequency bandwidth than conventional systems incorporating a tip mass.

Abstract: An apparatus and method for providing a torque to an external member to assist in twisting or deforming the external member. In one implementation the apparatus is useful for providing a force to a torque tube to assist in rotating, bending or twisting a wing, an airfoil, or a rotorcraft blade. The apparatus includes at least one biasing member which provides a biasing force to a linkage assembly, where the linkage assembly is pivotally coupled to a torque tube. The torque tube is fixedly coupled to the structure which needs to be bent, twisted or flexed. The energy stored in the biasing member provides the great majority of mechanical force required to rotate the torque tube and bend, twist or deform the structure when the structure is urged back into an unflexed or un-deformed state, the energy stored in the structure is transferred back to the apparatus.