Using permanent magnetic array device to detumble and despin defunct spacecraft

For the mission of detumbling and despinning the space debris, like defunct satellites, it is highly reliable and safe to use the permanent magnetic array device (PMAD). Based on the electromagnetic principle, the target's attitude dynamics is analysed, the electromagnetic torque is studied, the formula of electromagnetic force is simplified, and the stability of the nutation Angle is obtained. The rotation speed and attitude of PMAD are controlled by a dual-manipulator space robot to ensure that the component of the torque on the spin axis is zero. So the target will be only affected by the transverse component of the torque, and then the nutation angle decreases gradually to zero. When mission completed, the dual-manipulator space robot can deorbit or maintain on-orbit servicing, which is a significant exploration. (paper)