|
Piezoelectric materials have been investigated for vibration control in various engineering applications. Passive and active control techniques using piezoelectric materials are among the most important ones in the literature of vibration control. However, passive techniques present a good performance over a narrow frequency bandwidth. On the other hand, although active techniques require external power sources, sensor and actuators, they usually provide a good control performance over a wider range of frequency. To overcome the drawbacks of passive and active techniques, authors have focused on the nonlinear treatment of voltage output of the piezoelectric materials. A particular nonlinear technique, named Synchronized Switch Stiffness Control (SSSC), changes the stiffness of the structure through softening or hardening nonlinearities. The motivation is to ensure that the structure is excited out of its resonance frequency, preventing large displacements. The use of the SSSC technique has already been reported in the literature. However, few works show a circuitry that reproduces the SSSC technique. Furthermore, reported SSSC topologies allow only a hardening or softening effects. This work presents a novel adaptive SSSC piezoelectric circuit that combines the hardening and softening effects, significantly reducing mechanical amplitudes over a wide range of frequencies. The proposed SSSC circuit uses two piezoceramic patches (one as sensor and one as the stiffness actuator) and two symmetrical voltage sources. In the final version of the paper, experimental verifications of numerical predictions will be provided.
|
