The integrated dynamics modeling and coupling analysis for orbit and attitude of spacecrafts

For some special missions such as tumbling target docking which may not use inertial spindle docking, it is need to establish a non-centroid relative motion model which cause the coupling between the orbit and attitude. Aiming at the problem of orbital and attitude coupling during the close operation of the spacecraft, the relative posture integrated model of centroid (RPMC) is established based on the dual quaternion and the basic principles of mechanics. Meanwhile, considering the effect of non-centroid docking on the posture coupling, the relative posture integrated model of non-centroid (RPMNC) is also constructed. Then, the posture coupling of the two models is analyzed by the control variable method. The physical causes of coupling are defined and the key coupling parameters are determined. And the influence of the coupling terms in the two models on the relative posture of the spacecraft and are analyzed by changing the modulus and dimension of the coupling terms.