PERFORMANCE OF SUPERCONDUCTING MAGNETIC BEARINGS IN AN ADVANCED MOMENTUM EXCHANGE EFFECTOR

ANGULAR MOMENTUM EXCHANGE EFFECTORS HAVE SEVERAL ADVANTAGES OVER THRUSTERS. THESE INCLUDE REDUCED MAINTENANCE (FLUID MUST BE PERIODICALLY REPLACED) AND IMPROVED COMPATIBILITY WITH OPTICS (NO EFFLUENTS). HIGH-RATE SLEWING OF LARGE PAYLOADS, HOWEVER, WILL REQUIRE TORQUES (TENS OF THOUSANDS OF NEWTON-METERS) AND ANGULAR MOMENTUM STORAGE CAPACITIES (TENS OF THOUSANDS OF NEWTON-METER-SECONDS) THAT ARE LARGE IN COMPARISON TO THE CAPABILITIES OF AVAILABLE ANGULARMOMENTUM EXCHANGE HARDWARE. ONE REASON IS THAT HIGH TORQUE PRODUCES AN EXTREMELY DIFFICULT DESIGN CONSTRAINT FOR HIGH INSTRUMENT-GRADE MECHANICAL BEARINGS AND CONVENTIONAL MAGNETIC BEARINGS. FOR CONVENTIONAL MAGNETIC BEARINGS, HIGHTORQUES REQUIRE THAT THE MAGNETIC STRUCTURE BE EXCESSIVELY MASSIVE. AN ALTERNATIVE DESIGN EMPLOYS A SUPERCONDUCTING COIL IN THE MAGNETIC BEARING AND ELIMINATES ALL CONVENTIONAL MAGNETIC STRUCTURES IN ORDER TO PRODUCE A VIABLE HIGH-TORQUE MOMENTUMEXCHANGE EFFECTOR. THE MAGNETIC BEARING IS ALSO USED TO FULLY GIMBAL THE SUSPENDED ROTOR OF THE SLEW ACTUATOR. THE PROPOSED PHASE I RESEARCH WILL RESULT IN A DETAILED ANALYSISOF THE PERFORMANCE OF THIS ADVANCED CONTROL MOMENT GYRO. A LABORATORY DEMONSTRATION INCORPORATING CONVENTIONAL TECHNOLOGIES WILL ALSO BE DESIGNED DURING PHASE I. CONSTRUCTION AND TESTING OF THE HARDWARE WILL BE PERFORMED AS A PHASE II EFFORT.