Summary: | The use of fractionated spacecraft systems in on-orbit spacecraft assembly has the potential to provide benefits to both the defense and civil space community. To this end, much research must be conducted to develop and prove the requisite technologies to achieve these benefits. This thesis contributes to that effort by presenting the design and system integration, operating procedures and software development for a prototype three Degrees-Of-Freedom (DOF) Spacecraft Simulator. This simulator will be used in the Proximity Operations Simulator Facility, as part of the Naval Postgraduate School's Spacecraft Robotics Laboratory, to simulate autonomous guidance, navigation and control (GNC) for spacecraft proximity operations and assembly within the framework of the Autonomous Multi-Agent Physically Interacting Spacecraft project. The new spacecraft simulator includes several key enhancements over the previous Autonomous Docking and Spacecraft Servicing Simulator (AUDASS) developed in 2005 including a smaller and more agile structure, reduced air consumption and a Miniature Single-Gimbaled Control-Moment-Gyroscope (MSGCMG) to provide the necessary torque about the rotation axis. The MSGCMG in the simulator is a low-cost, low-mass, easily controlled momentum exchange device with a high torque to required power ratio. Furthermore, it provides the vehicle with high slew-rate capability, a key measure of performance in on orbit spacecraft assembly. Simulation and experimental results are presented for the prototype AMPHIS vehicle, demonstrating a potential slew-rate of 4.8 deg/s for a 30 degree rest-to-rest maneuver. The ultimate goal of this thesis is to provide the design specifications, combined with the necessary documentation and software development, for the prototype vehicle of the testbed for the AMPHIS project. The work conducted in fabricating the prototype vehicle will enable rapid fabrication of two additional vehicles which will provide an essential hardware-in-the-loop capability for experimentation with evolving control algorithms, sensors and mating mechanisms to be used for autonomous spacecraft assembly.
|