Active Vibration Control of Time-Varying Structural Systems with a Logic FxLMS Algorithm

Abstract

The filtered-x least mean square (FxLMS) algorithm has been widely used in active noise and vibration control of time-varying structural systems, where the secondary path is estimated online by injecting an auxiliary signal. However, the continuous injection of an auxiliary signal will increase the residual error. In this paper, a logic unit is proposed to remove such a drawback from the LMS-based control algorithm. The logic unit decides whether to start/stop injecting an auxiliary signal. The start procedure (SAP) and stop procedure (SOP) send out trigger signals of the logic unit. A flexible structure, which has a time-varying concentrated mass, was established to investigate the adaptive control method. Simulation and experiments were conducted to verify the feasibility and effectiveness of the logic unit. The results have proved that the adaptive control method with the logic unit can suppress vibration effectively in the presence of time-varying dynamics.