Study On Control Problems For The Leader-Follower Satellite Formation

With the continually progressing of space technology, the mankind's explorations to the space resources become more extensive. The control technology for leader-follower satellite formation flying is the basic issue of the space services and counterspace applications. The research on these key problems would be great support for the development of satellite formation flying applications. This dissertation studies the control problems of the leader-follower satellite formation flying, based on the non- collaborated target's service application. The main work and achievements are summarized as follows:(1) The design problems for the leader-follower satellite formation are studied. The definitions and the relative dynamics equations involved in the leader-follower satellite formation flying application are presented. Based on those, the formation design scheme is proposed under the flying task's constrains. The initial conditions for the formation's initialization are derived. The typical formation parameters are also presented, which would be the foundation of the leader-follower satellite formation's design.(2) The rendezvous control and optimization problems are studied. After the analysis of rendezvous problems related to the leader-follower satellite formation flying application, the control theory based on Lambert impulse rendezvous algorithm are studied. An iterative algorithm for optimal dual-impulse rendezvous incorporating ground observations is proposed. The Multi-Neighborhood Improved Particle Swarm Optimization Algorithm (MNI-PSO) is proposed, for the purpose of improving the capability of the standard Particle Swarm Optimization (PSO). The optimization results of the classical testing problems show that, the MNI-PSO has performed a great capability for the complex optimization problems, and its performance is better than some another popular algorithms. After that, the optimization scheme of the limited thrust rendezvous based on MNI-PSO is proposed, which solved the rendezvous control and optimization problems.(3) The autonomous navigation problems for the leader-follower satellite formation are studied. Focused on the relative navigation problems for the leader-follower satellite formation flying application, a dummy variable expression of the measuring parameters and matrix is proposed, avoiding the complex calculation for the Jacobi matrix. The online estimation of the model error covariance matrix is formulated to adapt the formation changing. Based on those above, the navigation algorithm of adaptive extended Kalman filter is presented, which is rapid convergence and has a high estimate precision. For the purpose of increasing the estimate precision of steady state, the navigation algorithm based on the Spherical Simplex Unscented Transformation Kalman Filter (SSUKF) is proposed. The algorithm's estimate precision is better than extended Kalman filter obviously.(4) The formation control problems for the leader-follower satellite formation are studied. Under the basic assumptions of control problems and typical scheme of nominal formation, the influences of the absolute orbit forecast decination are analyzed. The pulse-width modulation scheme is presented for the propulsion output modulation. An in-track direction drift transition formation is proposed for the leader-follower formation capture and reconfiguration under vision constrains. The Lyapunov control law basing ellipse reference orbit is proposed, which used for the leader-follower formation control under a large aberration. For the sake of improve the control abilities under steady state, the Linear Quadratic Regulator (LQR) control law basing on ellipse reference orbit is proposed, which separated into two independent controls in the orbit plane and orbit normal direction. The LQR control law has a high formation keeping precision.(5) The formation safeties of collision avoiding problems for the leader-follower satellite formation are studied. The factors affecting collision probabilities between formation-flying satellites are concluded and discussed. Solutions to those factors are proposed. The collision forecast strategy based on the quasi maximum instantaneous collision probability (Q-MICP) is proposed, for the collision monitoring problem of the formation-flying satellites. The calculation of the Q-MICP needs derivation of the minimum distance and happen epoch in the early-warning time period. The scaled step-size directly approaching (SSDA) algorithm is proposed creatively, based on the analysis of the derived function of the squared distance, for the pole searching of the function. It can solve the problem of the minimum distance's acquisition. The algorithm has improved the efficiency of collision forecast obviously.(6) The Distributed Interactive Simulation (DIS) problems for the leader-follower satellite formation are studied. Three-Level Design Pattern (TLDP) is proposed creatively, for the purpose of solving satellite formation DIS software design and development problems. The system design is presented for the satellite formation flying simulation, based on the TLDP. Through the detail analysis of the simulation data management tasks, the scheme of the Satellite Formation Simulation Data Management System (SFSDMS) is proposed creatively. The SFSDMS give us a universal tool for the data management of different simulations, which makes the data reuse more convenient.