Pointing Control Method For The Moving Part On Satellite

On-orbit satellites usually have moving parts and large solar pannels. In order tocomplete a specific task, moving part on satellite always should point to a target.Because of the interference of flexible solar pannels and the couple effectionbetween satellite and moving part, the problem of control system design becomesvery complicated. Aiming at the issue of moving part point to and track aNon-cooperative target in space in real-time, this thesis mainly studied designing ofthe control system. The detail contents are as follows.The mechanical structure of a satellite emission platform which equiped with atwo-degree-of-freedom rigid moving part and two solar pannels is designd, andkinernatics model of the satellite emission platform is established. Using EularEquation, the rigid dynamic model of the satellite emission platform is established.And on this basis, using concentrated mass method to set up the model of solarpannels, the coupled dynamic model is established finally.After linear processing of the coupled dynamic mode, rolling channel of thesatellite and yaw channel of the satellite are intercoupling, and as a whole isregarded as a double-input double-output system. An expected system matrix whichcan meet the requirement of response speed and steady-state error is designed. ThenCharcteristic Structure Configuration method is used to deal with the ModelMatching problem of the system. Otherwise, pitching channel of the satellite, rollingchannel of the moving part and yaw channel of the moving part are decoupled. Foreach of the three system, ouput value is subtracted by reference signal and the resultis integrated, then the augmented system is obtained. A set of desired closed-looppoles based on response speed is selected, then the pole placement method is used todesign the closed-loop control system. As pitching channel of the satellite wouldinterfered by solar pannels, so Bode diagram method is use to analysis the relativestability which is consist of amplitude margin and phase magin.The analytical expression of the azimuth position of a Non-cooperative target inspace is deduced. Based on the coupled dynamic model, the simulation model of thecontrol system of the satellite emission platform is put up in Matlab. The simulationresult shows that the response speed and steady-state error of the moving part’spointing to and tracking the Non-cooperative target in space both can achieve therequired performance indicators.