Abstract:

Using a hydraulically driven sixFOD motion simulator to simulate the vibration environment, there exist amplitude attenuation and phase lag due to the characteristics of closed loop amplitude and frequency responses of the simulator. Therefore, it is difficult to achieve accurate track and recurrence of high frequency random signals. To solve this problem, a vibration control strategy is proposed, which combines the joint space based and the operation space based control modes together. This strategy adopts the 3state control technology based on the classic PID together with the feedforward of the single cylinder control method. It can extend the frequency bandwidth of the system and achieve the accurate recurrence under the precondition of system stability. Experiment results show that the control strategy can make the sixDOF motion simulator to track the random signals of the range of 0.5 to 25 Hz and can control the recurrence error accuracy of random signals within ±3 dB. This strategy satisfies the performance index of the accurate recurrence.

Key words: automatic control technology, vibration control strategy, 3state control, 6DOF motion simulator, random signal, power spectral density error