Experimental Studies on Active Noise Control Using Smart Structures

The interior noise induced by vibration of surrounding structures can be attenuated by suppressing the vibration using surface-mounted smart elements. Compared with loudspeakers and microphones, piezoelectric elements are lightweight, compact, and easy to install. These features are very attractive for the noise control in vehicle cabins. Since the sound radiation abilities of different vibration modes are different, the control system has to be appropriately designed in such a way that the vibration components with strong radiation ability are controlled. In this paper, active noise control in a cylindrical shell with a floor partition using piezoelectric actuators (PZT) and Polyvinylidene fluoride (PVDF) error sensors is experimentally investigated. The control systems used in the experiment are designed using the GA-based method proposed in our previous work. To show the effectiveness of the optimal design, the performance of optimal systems is compared with that of non-optimal systems with random configurations. Experimental results are presented and analyzed both in the time and in the frequency domains. Results show that the control performance can be significantly improved through the optimal design using the GA-based method, even when controlled structures are irregular, where conventional design methods do not work well.