Study On Active Vibration Control Of Flexible Beam Using Piezoelectric Actuators

With the development of the aeronautics and aviation, flexible structures' using is a tendency. Flexible structures gain more and more attention, in the mean time, the vibration of flexible structures has becoming an obstacle of the application of the flexible structures. The thesis mainly focuses on the vibration active control of the flexible beam by using piezoelectric actuators.Chapter one, a brief introduction about the research background and significance of the thesis, and then give a summarization in the respect of flexible structures modeling, active/negative control, smart materials and its application in actuators and sensors field and so on. At last, present a brief exposition of the thesis.Chapter two, by use of dynamic equation and modal synthesis method, the flexible beam structure model is built. Give an introduction about the piezoelectric effect and piezoelectric equation, and then derive the output bending moment of piezoelectric actuators. Derive the voltage output equation of resistance strain sensors by means of mechanics of materials and electrical bridge. Finally, get the state equation of the flexible beam with piezoelectric actuators.Chapter three, mainly emphasize on the optimal displacement of actuators and sensors. In chapter two, have got the state equation of the flexible beam with the actuators. Choose the minimizing energy optimality criterion as the criterion of actuators and sensors displacement. By using genetic algorithm (GA), get the optimal displacement of the actuators/sensors, and make a comparison between the optimal and the others.Chapter four, mainly concern with the active control of the flexible beam. Introduce the Linear Quadratic to the flexible beam control. Design a control law of the flexible beam system. The results of the emulation prove the correctness of control law designed; in the mean time the results also validate the optimal displacement in chapter three.Chapter five, build experiment platform of the flexible beam's vibration active control. Give a detailed exposition about the hardware and software of the experiment system. Conduct the experiment, and the results of the experiment further validate the correctness of both the control law and the optimal displacement.Chapter six, summarize the thesis, propose the future direction of the research.