In impulsive orbital maneuvers, thrust vector misalignment from the center of mass is the serious source of disturbance torque. A high capacity attitude control system is needed to compensate the mentioned large exogenous disturbance. In this paper a new retrofiring control method is proposed and studied which is based on the combination of a 1DoF gimbaled thrust vector control and spin-stabilization method. Spin-axis stabilization and disturbance rejection are considered as two important attitude control objectives. The nonlinear two-body dynamics of a small spacecraft is derived in which dynamical interaction between the nozzle and the body is significant. Reaction control system is not used and the only active control part is a 1DoF gimbal. The spacecraft design efficiency is very important; therefore, the H∞ performance and control gain norm are chosen as two conflicting cost function in the Pareto front multiobjective optimization. Many Pareto fronts are given for some ranges of two favorable parameters: (1) spin rate and (2) spin-axis moment of inertia. Optimization variables are the closed-loop system poles. Moreover, poles region constraint is employed to obtain a well-damped transient response. From the perspective of performance and design efficiency, the optimization results give many attractive outcomes. The resulting system is an efficient design for a small spacecraft. Furthermore, numerical simulations are included to confirm the optimization results and illustrate the superiority of the proposed method compared to the only spin-stabilization.

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In this paper, a novel thrusting manoeuvre control scheme is proposed for a small spacecraft which is based only on the gimbaled thrust vector control (TVC) system. The spacecraft structure is composed of a body and a gimbaled thruster where common attitude control systems such as reaction control system (RCS) and spin stabilisation are not employed. A nonlinear two-body model is considered for the characterisation of the gimbaled-nozzle spacecraft where the gimbal actuator provides the only active control input. The spacecraft attitude is affected by a large exogenous disturbance torque which is generated by a thrust vector misalignment from the centre of mass (CM). To achieve some performance goals in the both transient and steady-state modes, a new control scheme is derived based on the combination of two linear and nonlinear controllers. The proposed method ensures the attitude and thrust vector stability during an impulsive orbital manoeuvre while eliminating and rejecting an exogenous disturbance torque. The numerical simulations illustrate the applicability of this method for using in a small spacecraft and its efficiency in sustained operation.