Wavefront Control Strategies for Large Active Thin Shell Primaries with Unimorph Actuators

This paper presents various aspects of the wavefront control strategies for an ultra-lightweight composite reflector made polymers large primary a space telescope, and shape is by set patterned unimorph strain actuators attached to reflector. It starts with analytical investigation mechanical behaviors strain-actuated curved shell, resulting in accurate prediction typical features, such as damped wave deformation at transition between electrodes limited morphing amplitude “print-through” actuation, which indicates that curvature-induced rigidity deteriorates performances forming accuracy active stroke actuators. The capabilities are evaluated both petal-like segmented monolithic configured reflectors numerical tests on target shapes Zernike modes patternings electrodes, structural dynamics examined. Finally, compound strategy proposed, uses deformable relay mirror compensate residual surface error corrected partially mirror, showing great relaxation budget thin-shell primary, especially on-axis observation.