[01] Timothy Sands, Mechanical Engineering Department, Stanford University, Stanford, USA. [02] Jae Jun Kim, Mechanical and Aerospace Engineering Department, Naval Postgraduate School, Monterey, USA. [03] Brij Agrawal, Mechanical and Aerospace Engineering Department, Naval Postgraduate School, Monterey, USA.

Two objectives dominate consideration of control moment gyroscopes (CMGs) for spacecraft maneuvers: High torque (or equivalently momentum) and singularity-free operations. Utilizing a 3/4 CMG skewed-pyramid the optimal singularity-free configuration is revealed. Next, this paper develops a decoupled control strategy to reduce the remaining singular conditions. Analysis and simulation is provided to justify the argument with experimental verification performed on a free-floating satellite simulator. Furthermore, a singularity penetration algorithm is developed, simulated, and experimentally proven to fly through singularities even without singularity reduction.

Singularity, Inversion, Deficient, Jacobi, Singularity Reduction, Singularity Minimization, Singularity Penetration

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