Sky-Hook with Adaptive Disturbance Cancellation Control for Flexible Structures with an Active Vibration Control Unit

Abstract

This study presents an Active Wheel Damper (AWD) unit that can be easily mounted on flexible structures such as cantilever beams. The AWD uses a gyro sensor to directly measure the absolute angular velocity, which is the rotational velocity of the slope angle of a deflection curve caused by the flexible vibration of the structure, and can be used to realize a skyhook control by the direct feedback of the angular velocity. This study proposes a Sky-hook With Adaptive Disturbance Cancellation (SWADC) control—which is constructed as a combined skyhook control and an adaptive disturbance cancellation control system—to enhance the capability of the AWD unit to suppress vibrations. An adaptive algorithm, which estimates the frequency of vibration of a structure in real time, is derived on the basis of an adaptive notch filter algorithm. The estimated frequency is used to model a disturbance observer that estimates harmonic disturbances. This study demonstrates the vibration-suppression performance of the AWD unit by numerical simulations and experiments.