| Vibration of spacecraft solar panels will seriously affect both attitude's stability and pointing precision of spacecraft, even cause structural destruction. Thus, vibration control of spacecraft solar panels is imperative. However, vibration control of spacecraft solar panels is always one of the major difficult problems in the aerospace control area. Up to now, the key techniques possessed by foreign scientists and technicians for vibration control of spacecraft solar panels are not published. And, the related problems which have been researched by domestic scientists and technicians have still not resaved. For the purpose of solving the problems, in this dissertation, the theory and techniques of vibration control of spacecraft solar panels are investigated systematically and deeply through theoretical deduction, numerical simulation and experimental research. The main research efforts in this dissertation are summarized as follows.1. The dynamic models of spacecraft smart solar panels structure are established, and the analysis for the characteristics of the thermo-mechanical -electric coupled structural dynamic system are implemented.(1) A concept of smart soalr panels structure employing control unit with piezoelectric materials is proposed. Making use of the thermo-mechanical-electric coupled characteristics, an electric potential distribution model ,which can describe the nonlinear electric potential induced by structural deformation, is developed. Based on this model, a fundamental theory for thermo-mechanical-electric coupled dynamic modeling is proposed .(2) The thermo-mechanical-electric coupled dynamic model is developed for three kinds of smart solar panels structural models according to the proposed theory. These structural models consist of smart beam-model structure describing main bending vibration of solar panel, smart plate-model structure describing bending and torsion vibration of solar panel, and the general smart solar panel structure.(3) Numerical simulations are carried out for analyzing the distribution property of electric potential, thermo-mechanical-electric coupled characteristics and structural dynamic behavior of smart solar panels structure .The theoretical results obtained above are the theory basis for designing the decentralized vibration control system of smart solar panels structure.2. The decentralized output feedback vibration control theories for spacecraft smart solar panels structure are proposed.(1) The key index of allocating control unit for smart solar panels structure is introduced based on the H2 norm of vibration modes. The locations of control units are determined according to the index, which is calculated according to the H2 norm contribution of control units for the modes. (2) Based on the placement characteristics of the control units, a low-rank balanced model reduction technique is proposed for high-dimensional structural vibration control system. Based upon the relationship between the Gram matrix and the position and velocity of the vibration structure, the Gram matrix based on singular value decomposition reduction technique is proposed. Applying these two techniques, the reduction problem of high dimensional vibration control system of smart solar panels structure are solved.(3) Decentralized output feedback vibration control theories are proposed for the reduced vibration control system of smart solar panels structure. These theories consist of decentralized static cost guaranteed output feedback vibration control theory, decentralized H∞dynamic output feedback vibration control theory and decentralized robust H∞dynamic output feedback vibration control theory.(4) Decentralized output feedback vibration controllers are designed based on these theories. The characteristic of decentralized output feedback vibration control system of smart solar panels structure are analyzed through numerical simulation. The researches above establish the significant technical basis for vibration control designing of smart solar panels structure.3. Vibration control experimental systems of spacecraft smart solar panels structure are constructed. Experiments of structural dynamic characteristic and decentralized vibration control are carried out.(1) Composite plates consisting of aluminum honeycomb and carbon fiber are manufactured, whose frequencies are equal to the general spacecraft soalr panels. The experimental smart solar panels structures are developed through mounting control units, which are smart single-panel structure and smart multi-panel structure. The control devices such as vibration measuring module and piezo-electro-ceramics driver are prepared. The locations of control units are designed based on the theory presented in this dissertation. The program of on-line vibration control are programmed. Thus, the vibration control experimental systems for smart soalr panels structure are constructed.(2) Several experimental researches are carried out for testing the characteristics of the smart single-panel structure. Such as experiments for structural dynamic characteristic, dynamic response under initial displacement disturbance, resonance excitation of fundamental frequency and decentralized static output feedback vibration control for the structural system under resonance excitation of fundamental frequency.(3) Several experimental researches are carried out for testing the characteristics of the smart multi-panel structure. Such as the experiments of structural dynamic characteristic, vibration control under wide-angle attitude maneuver disturbance and random disturbance are carried out for smart multi-panels structure.The experimental results partly demonstrate the correctness and effectiveness of the dynamic models and control theory proposed in this dissertation, which are structural dynamic models, decentralized static output feedback vibration control theory, decentralized robust H∞dynamic output feedback vibration control theory, placement method of control units and so on.
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