Adaptive Control of a SpinStabilized Spacecraft Using two Reaction Wheels and a 1DoF Gimbaled-Thruster

In impulsive orbital maneuvers, a large disturbance torque is generated by the thrust vector misalignment from the center of mass (C.M). The purpose of this paper is to reject the mentioned disturbance and stabilize the spacecraft attitude, based on the combination of a one degree of freedom (1DoF) gimbaled-thruster, two reaction wheels (RWs) and spin-stabilization. In this paper, the disturbances are assumed to be unknown and reaction control systems (RCS) are not employed. The nonlinear two-body dynamics of the proposed system is formulated and validated by the Simmechanics model. The closed-loop controller includes a full state feedback controller based on the gimbal actuator, a self-tuning controller (STC) based on the two RWs and a least squares based disturbance estimator. The simulation results are given by which the applicability of the proposed method is illustrated.