Coordinated attitude control for Tethered Space Robot

Tethered Space Robot (TSR) is a new kind of space robot, which consists of robot platform, space tether and operational robot. The operational robot should control its attitude for adjusting to target attitude before starting on-orbit service. According to attitude control problem of operational robot, this paper proposes one kind of coordinated attitude control method utilizing space tether and reaction wheel. Firstly, orbital dynamics model and attitude kinematics model are established. Then the PD controller is designed by using of space tether for controlling orbital plane attitude angle. The control algorithm of three axis attitude is implemented utilizing feedback linearization principle, which provides roll, pitch and yaw torques. The torque is obtained by moving tether attachment and reaction wheel rotating. Numerical results are presented, demonstrating the validity of tracking desired attitude angle.