Piezoelectric Single Crystal Applications

Piezoelectric single crystals have the potential to revolutionize the field of active structures. Mid¿ proposed to capitalize on the large stroke character of these materials by implementing them onto a helicopter rotor blade for the primary purpose ofsolving the blade tracking problem. Once implemented, however, because of the improvements made to the X-Frame actuator design, much greater output energies will be evident. Work will focus both on demonstrating the predicted performance levels for thisactuation system in the lab and in verifying that this level of performance is adequate for primary flight control of the helicopter. If experimental results fall short of the performance levels needed for primary flight control, recommendations will bemade to improve system response. The results from these studies and laboratory experiments will serve as a springboard to Phase II efforts at implementing the proposed system in a hover and/or wind-tunnel test.The blade tracking problem is a costlyexpense amounting to between $200- $400M a year in operational costs. By combining single crystal piezoelectrics with a proven rotor blade trailing edge servo-flap actuation system, a viable solution to this problem is well within reach. Furthermore,because of the high bandwidth properties of the single crystal, along with the improvements in X-Frame technology, the problems of higher harmonic, cyclic, and possibly even collective rotor control are also within reach. By developing a rotor controlsystem independent of the swashplate, a tremendous savings in rotorcraft maintenance and operational costs is achieved. Successfully breaking into either of these markets is the main goal of this proposed effort.Other markets that will also benefit from developing a highly energetic actuation system are:¿ Control of fast acting valves, such as in automotive engines¿ Quieting of plant vibrations and noise, in, for example, heavy industries such as paper milling.¿ Machine tools (Mid¿ has already product prototypes in the area)¿ Control of computer printer heads to provide faster printer speeds¿ Control of photolithography components in the semi-conductor industry and components in the optical industry.