| Non-cooperative spacecraft denotes any spacecraft which can’t provide itsposition and attitude information and control the orbit and attitude which caused thespacecraft to tumble and maneuver irregularly. The non-cooperative features of thetarget spacecraft bring the difficulties of the model and measurement for the study ofthe relative orbit maneuver. So far, researchers began to discuss several aspects asfollows: the relative motion model formulation; the non-cooperative features causedthe model uncertainty and relative state information difficultly to access.The study focused on the above problems. More specifically, these main results inthe dissertation consist of several parts as follows:Firstly, based on the introduction to the research background, on-orbit servingtechnology development and existing results on the topics, the main contents andstructure organization of the dissertation are given.Secondly, the movement characteristics of the non-cooperative spacecrafts and itsinfluences on the control strategy of the different tasks are analyzed. The circular orbitrelative motion model and the relative motion model in line of sight frame are derived.Based on the equations, the uncontrolled relative motion characters are studied.Thirdly, based on the relative motion model in line of sight frame, the line ofsight guidance law is designed. The vertical control law is on-off control; the lateralcontrol law is proportional navigation guidance law initially, which is replaced by theon-off control finally. The numerical examples illustrate the effectiveness of theproposed control design method, but the method can’t control the angle of sight.Finally, the feed forward and feedback control algorithm is designed based on theassumption that the thrust is continuous. And the linear control algorithm is designedbased on the linear model of system which is obtained by using linearization method.A numerical example is given to illustrate the developed method. |
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