Pulse-Width Modulated Control via Singular Perturbation for a Spacecraft Attitude Maneuver
The problem of controller design for a single-axis spacecraft reorientation maneuver in the presence of high-frequency pulse-width modulation (PWM) feedback is addressed. The Filippov's average PWM spacecraft attitude model controlled by a smooth function is used as the basis for a dynamical feedback controller design such that the controller dynamics is a singular perturbation with respect to the spacecraft dynamics. The explicit expressions for evaluation of the controller parameters are derived by fast and slow modes analysis that are induced in the closed-loop systems. The presented design methodology guarantees desired behavior for the Cayley-Rodrigues attitude parameter in the presence of nonlinearity and uncertainty of the spacecraft model. Simulation results are presented.