Piezoelectric adaptive active vibration suppression for wind-tunnel model support sting

Due to flow separation and turbulence, the slender cantilever aircraft model support system is prone to low-frequency and large-amplitude resonance in the wind tunnel tests, resulting in a decrease in test data quality, a limited test envelope, and even threatening the safe operation of the wind tunnel. A piezoelectric active damping system based on the filtered-x least mean square algorithm is proposed to effectively suppress the vibration of the wind-tunnel model support sting. Firstly, a modified variable step least mean square algorithm is proposed to address the issue that the fixed-step algorithms limit each other in terms of convergence speed and steady-state error. Following that, a variable step filtered-x least mean square algorithm based on reference signal reconstruction is developed, and the corresponding feedback controller is designed to perform the ground tests of the piezoelectric active damping system for the wind-tunnel model support sting. The experimental results show that the proposed algorithm has a faster convergence speed and lower steady-state error than the traditional algorithms, as well as strong anti-noise and adaptive control abilities that significantly improve the active vibration suppression effect of the wind-tunnel model support sting.