Pointing and tracking control with linearization and state feedback for gimbal on floating platform

2-DOF (degree of freedom) gimbal mounted on floating space platform caused attitude disturbance to the platform while pointing and tracking a space object. Therefore the attitude of platform was affected then the pointing direction of the end of the gimbal changed and the pointing accuracy was reduced. So the gimbal and the platform were dynamically coupled. This problem could not be ignored especially when the inertia of the gimbal was not small enough compared to that of the platform or when the gimbal was rotating fast. In order to solve this problem, a coupling compensation method was put forward. In this method, attitude motion of platform caused by the rotation of gimbal was considered to revise the tracking target of the gimbal. Furthermore, feedback linearized state feedback was used as control method. At last a simulation was carried out to compare the pointing accuracy between traditional PD control method and the method put forward. It is verified that the pointing accuracy is efficiently improved by using linearization and state feedback as control method.