Active Noncontact Shape Control of Preformed Membrane Mirrors and Antennas

Design and fabrication processes will be refined and developed to produce strong bidirectional strain effects in preformed doubly-curved piezoelectric membrane mirrors and antennas. High-precision active membrane shape control will be obtained with a noncontacting electron gun charge deposition technique. Control algorithms will be defined that allow the electron gun to provide actuation of selected areas of the membranes to correct the shape distortions caused by the space thermal environment and dynamics of spacecraft and instrument pointing. The efficacy of the bidirectional strain piezoelectric membrane in combination with the electron gun noncontact actuation will be verified by testing of piezoelectric membrane mirror models. The fabrication processes and active control approach are scaleable and can provide significant increase in membrane surface accuracy and reduction in volume and mass of large systems.