Self-sensing actuator for semi-active vibration suppression

This paper proposes and investigates a novel self-sensing method to estimate the state of a structure by using piezoelectric materials that are used as actuators for semi-active vibration suppression. The semi-active vibration suppression considered in this paper suppresses the vibration by controlling switches in the inductive shunt circuits for the piezoelectric actuators embedded in the structure. By using extended system equations, this self-sensing method is implemented with a Kalman filter instead of the conventional bridge circuit technique. This method is applicable to multiple-degree-of-freedom (MDDOF) structures with multiple piezoelectric actuators. The performance of the method is first investigated by performing numerical simulations of vibration suppression of a three-DOF mass-spring system. The numerical investigations show that the method works well on an MDOF structure under the influence of a residual mode, and that the method combined with the semi-active vibration suppression is significantly robust against parameter variations of the system. To investigate the performance of the method applied to more realistic structures, both numerical simulations and experiments of semi-active vibration suppression of a ten-bay truss structure are also performed by applying the method. The numerical and experimental results coincide well with each other, and demonstrate that the self-sensing method works well on the real structure.