Design and Analysis of On-Orbit Servicing Architectures for the Global Positioning System Constellation

Satellites are the only major Air Force systems with no maintenance, routine repair, or upgrade capability. The result is expensive satellites and a heavy reliance on access to space. At the same time, satellite design is maturing and reducing the cost to produce satellites with longer design lives. This works against the ability to keep the technology on satellites current without frequent replacement of those satellites. The Global Positioning System Joint Program Office realizes that it must change its mode of operations to quickly meet new requirements while minimizing cost. The possibility of using robotic servicing architectures to solve these problems is considered in this thesis. The authors accomplished this through a systems engineering and decision analysis approach in which a number of different alternatives for on-orbit satellite repair and upgrade were analyzed. This approach involved defining the problem framework and desired user benefits, then developing different system architectures and determining their performance with regard to the specified benefits. Finally, the authors used decision analysis to evaluate the alternative architectures in the context of the user's goals. The results indicate favorable benefit-to-cost relationships for on-orbit servicing architectures as compared to the current mode of operation.