Compound Control For Ascending And Descending Of Stratospheric Airship With Thermal Model

Multiple satellite formation flying has being studied extensively and receivedsignificant attention in recent decades. Formation flying enables several satellitesrunning on neighboring orbits to complete common space missions as a large virtualplatform through coordinated work. On the basis of the preliminary research ofnational satellite projects, this research is to provide theoretical and technical supportfor formation design and attitude coordination control for satellites in elliptical orbits.The main work of this thesis includes the following three aspects:(1) Several dynamical models were established, including nonlinear equations,Lawden equations, T-H equations, kinematic equations depicted with orbit elementdifferences. The relative motion was discussed under J2perturbation. It was foundthat kinematic equations were just the analytical solution of T-H equations.(2) Considering the complex of the relative motion, eight parameters wereemployed to address formation configuration. Four traditional formationconfigurations were designed. In application of MMS mission, tetrahedral formationwas also designed using multiple phase optimization method.(3) The scheme of coordinated attitude determination and control was designed.A weighted recursive linear attitude estimator was achieved via geometric analysis.The coordinated attitude controller was designed using non-singularity fast slidingmodel method.The key technologies and innovations in the research focus on the followingpoints:(1) Kinematic equations depicted with orbit element differences are equivalent toT-H equations.(2) Weighted recursive linear attitude estimator is proposed which can enhancethe attitude accuracy.