06.1 - Flight Dynamics and Control (Control & Modelling)
TWISTOR BASED 6-DOF DISTRIBUTED ADAPTIVE LEADER-FOLLOWING CONTROL FOR MULTIPLE RIGID SPACECRAFT FORMATION
B. Zhang¹, F. Li, China Academy of Launch Vehicle Technology, China; J. Bai¹; ¹Northwestern Polytechnical University, China
In the recently developed twistor framework, the consensus tracking problem of six-degree-of-freedom (6-DOF) leader-following spacecraft formation is investigated in the presence of uncertain mass property of the spacecraft and unknown external disturbances. A distributed adaptive controller is proposed to guarantee the consensus of the relative translational and rotation motion between the leader and followers is reached simultaneously. The 6-DOF dynamics of a rigid spacecraft modeled by twistors is presented and reformed to ease the design of the consensus protocol. By defining location neighborhood errors for each follower, a sliding mode variable is constructed, and the corresponding sliding surface is established. Then, a sliding mode controller for the 6-DOF formation is proposed. For the uncertain inertial parameters and unknown disturbances, adaptive laws are developed to get their estimates to substitute for the unknowns in the sliding mode controller. The stability of the closed-loop system is proved via Lyapunov stability theory. Finally, numerical simulations are conducted to demonstrate the effectiveness of the proposed protocol.