Dynamic Modeling and Control of Slewing Smart Beam

摘要

This research is concerned with the modeling and active vibration control of slewing smart structures. When cantilever beam rotates about axes perpendicular to the undeformed beam's longitudinal axis, it experiences inertial loading. Hence, the beam vibrates during and after slewing. In this paper, the analytical model for a single slewing flexible beam with surface bonded piezoelectric sensor and actuator is first developed using the Hamilton's principle with discretization by the assumed mode method. The theoretical frequency response function is then compared to the experimental open loop frequency response data. It is found from the comparison that the rotor friction should be included in the modeling. A new concept is introduced to incorporate the effect of the friction. As a result, the use of coupling factor is proposed in this paper. The positive position feedback (PPF) controller is designed for the suppression of residual vibrations after slewing. The experimental results show that it can suppress the vibration effectively but cannot alleviate the vibrations occurred during slewing. This problem is discussed in detail in this paper.