| In recent years the active vibration control of piezoelectric intelligent structures has experienced great development and attracted lots of researchers both in home and abroad, in which two basic theories often applied are modal space control and optimum control. However, some problems encountered in the three stages of set up for control system remain unresolved. This dissertation takes modal space control and optimum control as basis to investigate those problems, but only concentrates on the pinned surface-bonded kind of structures. The first optimization is realized by the application of perturbation finite element method to update the original dynamic model to be controlled; then based in modal space control method weighting matrices in linear quadrate optimal theory are treated, and independent/coupled combinative control and active/passive hybrid control are formulated and presented; next, as to the realization of control system, maximum rules for the locations of piezosensors/ piezoactuators are presented and the theory and application of time-sharing self- sensing piezoactuators studied; finally numeric results of a two layers space frame and experimental research are introduced. All the works in this paper is included in the project named "intelligent mechanical structures and systems" supported by the National Natural Science Foundation of China (59635140); Doctor Point Fund of National Education Committee; Parent Company Fund of Aviation Industry, and it is also one part of the project named "the research of some basic problems in mechanical systems", the National Natural Science Foundation of China (50135030). Content as follows:1. Briefly discussion of the concept of intelligent structure, and then review for the development and application of piezoelectric intelligent structures, and then the goal of this paper. 2. Presentation of the basis for the pinned surface-bonded piezoelectric intelligent structures and its vibration control. Include: FEM models of beam or plate, dynamic equations in closed loop, piezo-sensing and piezo-actuating formulas, optimal location method for both sensor and actuator, linear quadrate optimization theory, perturbation finite element method(P-FEM).3. This chapter consists three parts: the updating of FEM model; optimal selection of weighting matrices in LQR; active vibration control of a plate with piezosensors and piezoactuators, mainly the determination of the optimal location for sensors and actuators. 4. Investigation for two methods to improve control performance: first, the so called independent/coupled modal space combinative control, which has the advantages of both independent modal control and coupled modal control, and can trace the variation of structural main vibrating modes and control them with more efficiency, therefore, the control of more than one mode in system can be realized by using fewer actuators while the system performance features are improved under lower power consumption and quicker response to external excitation. Second, the active and passive hybrid control, which combines active modal space control and passive damping control into one design. Damping can reduce the overflows in modal control, especially in high modes, so the combination has the merits of improving control stability and performance.5. The study for time sharing self-sensing piezoelectric actuator: By applying PZT's piezo-effect and piezoelectric converse effect, a new type of self-sensing actuator based on time-sharing was presented, which can switch over from sensor to actuator, or vice versa. That is to act as a sensor at one time-span and an actuator at next time-span, and the cycling keeps on, thus realized the different performances with only one PZT patch. The probability of its application in vibration control is also discussed, the advantages are that it can give precise co-positions for actuators and sensors, and cut down controlling power consumption and easy to handle. Having carried out the experimental study of piezoelectric self-sensing...
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