Using piezoelectric impact absorbers on vibration control of structures

This paper presents vibration reduction effect of a cantilever beam by using piezoelectric impact absorbers. The system considered here is a metal cantilever beam subjected to an external harmonic force applied near the free end. There are two piezoelectric impact absorbers symmetrically attached to both sides of the beam. A traditional piezoelectric absorber usually consists of a piezoelectric sheet, inductance, and resistance. The traditional absorbers with a carefully chosen natural frequency and damping ratio can be used to reduce the vibrating amplitude of the beam. Then, an additional diode is used in the absorber for simulating the mechanical impact by switching the circuit on and off. The impact effect is expected to dissipate more energy of the system. The equations of motion of the composite cantilever beam, including the beam itself and two attached piezoelectric sheets, are derived by Hamilton's principle and discretized by Galerkin's method. Then, the equations of motion of the beam and the circuit equations of impact absorbers are solved simultaneously. The numerical results show that piezoelectric impact absorbers are more effective, in vibration reduction, than the traditional piezoelectric absorbers. The reduction efficiency can be affected by the design of the impact absorber, the position of attached piezoelectric sheets, and the parameters of the absorber. This paper also gives suggestions about choosing system parameters to achieve more attenuation of vibration.