THE GOAL OF THIS PROJECT IS TO DEVELOP AND DEMONSTRATE A RELIABLE, FAULT-TOLERANT WAVEFRONT CONTROL SYSTEM…

Public award description

THE GOAL OF THIS PROJECT IS TO DEVELOP AND DEMONSTRATE A RELIABLE, FAULT-TOLERANT WAVEFRONT CONTROL SYSTEM THAT WILL FILL A CRITICAL TECHNOLOGY GAP IN NASA'S VISION FOR FUTURE CORONAGRAPHIC OBSERVATORIES. THE PROJECT OUTCOMES INCLUDE INNOVATIVE ADVANCES IN COMPONENT DESIGN AND FABRICATION AND SUBSTANTIAL PROGRESS IN DEVELOPMENT OF HIGH-RESOLUTION DEFORMABLE MIRRORS (DM) SUITABLE FOR SPACE-BASED OPERATION. SPACE-BASED TELESCOPES HAVE BECOME INDISPENSIBLE IN ADVANCING THE FRONTIERS OF ASTROPHYSICS. OVER THE PAST DECADE NASA HAS PIONEERED CORONAGRAPHIC INSTRUMENT CONCEPTS AND TEST BEDS TO PROVIDE A FOUNDATION FOR EXPLORING FEASIBILITY OF NEW APPROACHES TO HIGH-CONTRAST IMAGING AND SPECTROSCOPY. FROM THIS WORK, NASA HAS IDENTIFIED A CURRENT TECHNOLOGY NEED FOR COMPACT, ULTRA-PRECISE, MULTI-THOUSAND ACTUATOR DM DEVICES. BOSTON MICROMACHINES CORPORATION HAS DEVELOPED MICROELECTROMECHANICAL SYSTEMS (MEMS) DMS THAT REPRESENT THE STATE-OF-THE-ART FOR SCALABLE, SMALL-STROKE HIGH-PRECISION WAVEFRONT CONTROL. THE EMERGING CLASS OF HIGH-RESOLUTION DMS PIONEERED BY THE PROJECT TEAM HAS ALREADY BEEN SHOWN TO BE COMPACT, LOW-POWER, PRECISE, AND REPEATABLE. THIS PROJECT WILL DEVELOP A SYSTEM THAT ELIMINATES THE LEADING CAUSE OF SINGLE ACTUATOR FAILURES IN ELECTROSTATICALLY-ACTUATED WAVEFRONT CORRECTORS SNAP-THROUGH INSTABILITY AND SUBSEQUENT ELECTRODE SHORTING AND/OR ADHESION. TO ACHIEVE THIS WE WILL IMPLEMENT TWO INNOVATIVE, COMPLEMENTARY MODIFICATIONS TO THE MANUFACTURING PROCESS. WE WILL DEVELOP A DRIVE ELECTRONICS APPROACH THAT INHERENTLY LIMITS ACTUATOR ELECTRICAL CURRENT DENSITY GENERATED WHEN ACTUATOR SNAP-DOWN OCCURS, AND WE WILL MODIFY THE ACTUATOR DESIGN TO MITIGATE ADHESION BETWEEN CONTACTING SURFACES OF THE ACTUATOR FLEXURE AND FIXED BASE ELECTRODE IN THE EVENT OF SNAP-DOWN. PHASE II RESEARCH WILL COMBINE THE ACTUATOR DESIGN AND FABRICATION PROCESSES, AND CURRENT-LIMITING DRIVE ELECTRONICS TO PRODUCE A MEMS DM WITH 3072 ACTUATORS WITH ENHANCED RELIABILITY.