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Full-Text Articles in Engineering
Autonomous Attitude Consensus For Nanosatellite Formations In Leo, Laird J. Mendelson
Autonomous Attitude Consensus For Nanosatellite Formations In Leo, Laird J. Mendelson
Master's Theses
Consensus strategies are examined as a possible approach to achieving attitude alignment for a large, close-proximity formation of nanosatellites in low earth orbit (LEO). An attitude-only distributed consensus approach is selected for further consideration due to its comparatively low data transmission requirements. The convergence of a connected network of satellites to the attitude agreement subspace under this control law is shown using a Lyapunov stability approach with a set of idealizing assumptions. A moderate-fidelity simulation demonstrates the performance of the control law under realistic conditions that violate those assumptions. Particular emphasis is placed on the conditions that arise from the …
Control Of A Spacecraft Using Mixed Momentum Exchange Devices, Blake J. Currie
Control Of A Spacecraft Using Mixed Momentum Exchange Devices, Blake J. Currie
Master's Theses
Hardware configurations, a control law, and a steering law are developed for a mixed hardware spacecraft that uses both control moment gyros and reaction wheels. Replacing one or more gyros in a spacecraft with a reaction wheel has potential for cost savings while still achieving much greater performance than using reaction wheels alone. Several simulated tests are run to compare the performance to a traditional all reaction wheel or all control moment gyro spacecraft, including analysis of failure modes and singular configurations. The mixed system performed similarly to all gyro systems, responding within 6% of the gyro system’s time for …
Modification Of The Cal Poly Spacecraft Simulator System For Robust Control Law Verification, Tomoyuki Kato
Modification Of The Cal Poly Spacecraft Simulator System For Robust Control Law Verification, Tomoyuki Kato
Master's Theses
The Cal Poly Spacecraft Dynamics Simulator, also known as the Pyramidal Reaction Wheel Platform (PRWP), is an air-bearing four reaction wheel spacecraft simulator designed to simulate the low-gravity, frictionless condition of the space environment and to test and validate spacecraft attitude control hardware and control laws through real-time motion tests. The PRWP system was modified to the new Mk.III configuration, which adopted the MATLAB xPC kernel for better real-time hardware control. Also the Litton LN-200 IMU was integrated onto the PRWP and replaced the previous attitude sensor. Through the comparison of various control laws through motion tests the Mk.III configuration …