A time delay forecasting method in complex vibration environment

This research is focused on the vibration control problems of the continuous distributed structure suffering from complex excitations. According to the acute displacement vibration which induced by first mode of the structure, design a single input and single output (SISO) control system. A high-order filter is introduced to process the high-frequency disturbance included in the output signal. In order to keep stable, the nonlinear time delay of the filter is discussed, and a forecasting method for eliminating the time delay is deeper studied. For getting the constant time delay system, the phase compensation method is induced for eliminating the nonlinear characteristic of the filter´s time delay. The forecasting method is performed effectively through establishing an ARMA model, and the coefficients of the model are defined by stochastic approximation method. A wind-tunnel model with rear sting is used as a distributed structure in experiments. The results reveal that the first mode vibrations of the model are effectively suppressed by this controller when the structure suffers complex excitations.