Abstract:

In the aerospace field, rigid-flexible coupling structures are widely used due to their high structural efficiency. However, the existence of the rigid-flexible coupling effect brings huge challenges to active vibration control. To solve this difficult problem, this paper conducts research on active vibration control as the research object. In terms of research methods, a vibration measurement and control platform for the three-flexible beam coupling system was first established. The detection and suppression of vibration signals were achieved by using piezoelectric sensors and drivers. On this basis, the design of vibration measurement and control algorithms was carried out. Subsequently, the system dynamics model was established by combining the finite element method with the Hamiltonian variational principle. The main modal shapes of the free vibration of the system were determined in the simulation environment. After introducing the modal coordinates, the modal truncation method was adopted to obtain the state space equation of the system. Meanwhile, in view of the uncertainty of model parameters, wavelet analysis and jumping spider optimization algorithm were used to accurately identify the parameters of the system state space equation. Furthermore, considering the nonlinearity and parameter uncertainty of the system, a fuzzy logic controller based on Gaussian membership function was designed to suppress the vibration of the flexible beam. The simulation and experimental results show that within the same control saturation voltage period, the fuzzy logic controller performs better than the large gain PD(Proportional and Derivative) control in suppressing the vibration of the coupled three-flexible beam. While rapidly suppressing large-value vibrations, it can suppress small-value vibrations at a faster speed. It effectively shortens the time for the system to reach a stable state and significantly improves the vibration control effect. To sum up, the fuzzy logic controller based on Gaussian membership function designed in this paper overcomes the problems of nonlinearity and parameter uncertainty in the vibration control of rigid-flexible coupling structures. Compared with the traditional high-gain PD control, it shows stronger adaptability and higher control efficiency.

Key words: coupled three flexible beam system, active vibration control, fuzzy logic controller, jumping spider optimization algorithm