Study on identification of bending and torsional modes for piezoelectric smart flexible cantilever plate

Some flexible appendages of spacecraft are cantilever plate structures, such as sun plate, piezoelectric smart structure is used to suppress the vibration due to the parameter uncertainties and environmental disturbances. A kind of optimal placement method for piezoelectric actuators/sensors was developed based on the degree of observability and controllability, and the experimental facility of piezoelectric smart plate for active vibration control was designed and built up. Combining two order Butterworth band-pass filter with multi-piezoceramic evenness, decouple of bending and torsional modes in measurement and control is realized, and the observe spillover and control spillover are solved. Identification of the flexible cantilever plate system is investigated, from this we can know the natural frequency and damping ratio of the system. The experimental results issue that the method presented is feasible.