Active Vibration Control Of A Conical Shell Using Piezoelectric Ceramics

Vibration in engineering systems usually causes equipment degradation or failure, results in people discomfort and potential safety problems and many other adverse consequences. Conical shell as a common engineering structure is widely used in aerospace, marine engineering, nuclear industry, petroleum engineering and so many engineering fields. So the study of its vibration characteristics and vibration suppression has practical application significance. Piezoelectric ceramic has excellent frequency response characteristic, high resolution characteristic, strong anti- interference ability and force output capacity, which are suitable for high frequency vibration control system as sensor and actuator.Firstly, piezoelectric ceramic two-dimensional sensor and actuator principle is theoretical analyzed, and its sensor and actuator equations are obtained from piezoelectric ceramic constitutive equations in this paper. Secondly, the modal characteristics and modeling of conical shell are studied. A finite element simulation is used to get natural frequency and modal information of conical shell with Ansys. A modal experiment is adopted and vibration data of two different measurement points with the same excitation point is got, and system identification results in frequency domain with experiment data verity the simulation results. As the same time it provides a basis for the paste position of piezoelectric sensors and actuators. Then choose NI acquisition and control module as hardware, program active vibration control software with Labview, use piezoelectric ceramics as sensors and actuators to build active vibration control system. At last, according to the vibration characteristics of conical shell, and on the premise of unable to get accurate mathematical model of it, an independent modal fuzzy sliding mode controller, which combines advantages of fuzzy control and sliding mode control, is designed, and achieve active vibration control of the first four modal. The experiment results in time and frequency domains have shown the active vibration system is effective and practicable.