High speed flywheels for integrated energy storage and attitude control

We present new results on attitude control of spacecraft with flywheels, where the wheels are also used to store energy as ''mechanical batteries.'' A brief review of the literature of this concept is given. The nonlinear equations of motion for a gyrostat model are given in dimensionless form, and recognized as a noncanonical Hamiltonian system. Decomposition of the space of internal torques separates the attitude control function from the energy storage function. A class of control laws is developed to execute large-angle rotational maneuvers while simultaneously performing energy storage and extraction operations.