Robust design of a spacecraft attitude tracking control system with actuator uncertainties

In this paper we apply the robust redesign for transient performance recovery of nonlinear systems with input uncertainties developed in [2] to a spacecraft attitude tracking problem with actuator uncertainties. We first extend the robust design of [2] to a generalized uncertainty structure. Next, we show that when the spin and transverse axis directions and/or the gains of the flywheel actuators are uncertain, the kinematic model of a spacecraft can be expressed in this structure. We apply the extended design to this spacecraft model, illustrate it with a simulation example, and numerically compute the permissible range of the uncertainties for which this design guarantees stability.