| With the development of astronautics, more and more flexible structures have been used into aerospace research. The application of large flexible structures result in adaptability of design and manufacture, improvement of performance and reduction of launch cost. At the same time, it also introduced serious vibration problems. The continual vibrations of flexible appendages not only affect the performance of appendages, but also significantly influence on moving accuracy and orientation stability of the main body. Additionally, prolonged vibration makes the fatigue of structures increased. In this thesis, active vibration control of foldable flexible structures with central rigid base — one typical kind of space structure, is thoroughly investigated. Based on reviewing active vibration control of large space flexible structure, the technique vacancy and main problems in this field are analyzed. Then the research plan of this thesis is determined: based on the principle of intelligent structures, use the control architecture of local control cooperated with global coordination to study active control of flexible multibody structures, and employ structural identification method to solve modeling difficulty in large complex flexible structure control. The main work accomplished is as follows:1. Overview of active vibration control of flexible space structures2. Analysis of coupling characteristic between central rigid body and its flexible appendages3. Study on control architecture of the coupled structure4. Similar human intelligent control of the central rigid body5. Decentralized modeling and control of flexible multibody structure6. Setup of experimental system and experiment researchFirst, coupling characteristic between flexible appendages and central rigid body is theoretically analyzed. Based on simplifying the object studied, its theoretical model is derived by applying Lagrange equation, and the coupling characteristic is analyzed. The control modals of flexible appendages are determined through calculating rolling couple coefficient and simulation of real coupling structure. Moreover, low vibration modals is derived with finite element method.Then, control strategy of central rigid base ---foldable flexible appendages coupling structures is studied. Based on analyzing limitation of centralized control architectures, decentralized control associate with global coordination is selected to control the coupling structure. Then similar human intelligent control method is selected to control movement of rolling base. In order to overcome modeling and control difficulty of flexible multibody structure, decentralized modeling method based on structural identification and decentralized predictive control is studied. The error rectification term is introduced into local controller design to overcome the influence of mismatched model and control input of other substructure. Then, global coordination controller is designed through rule base. Thus, a hierarchic controller of the coupled system, which consists of execution level, coordination level and organization level, is finished.In order to improve sensing and actuating performance of PZTs, auto configuration of PZTs function is presented and corresponding circuit is completed.Finally, on the base of all work above and present condition, the experimental system is built up in light of the space environment of weightlessness and weak damping where the coupled structure works, and the experiments is carried out. The experiment system consists of machinery system and control system. The former includes air-bearing table system, rolling base driving system, angular displacement sensing system, and two foldable flexible plates with piezoelectric patches bonded; the latter includes sensing signal processing and actuation signal generating circuits, and computer system composed of PC and two TMS320F240. Next, the ARX model of each flexible plate is derived by structural identification method, on which based local predictive controlle...
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