Experimental study of model-based feedforward control of longitudinal wave transmission through hollow cylinders

Experimental studies of closed-loop control of longitudinal wave transmission through a hollow cylinder are presented in this article. Model studies coupled with experimental modal analysis are used to understand and characterize the actuator-strut ensemble, and a boundary control algorithm, which falls under the class of feedforward control schemes, is experimentally implemented. The algorithm is based on a partial differential equations (PDE) model of the strut-actuator system, and a combination of strain and acceleration measurements are used to solve the boundary-value problem in the implementation. Harmonic vibratory disturbances are transmitted in the frequency range extending up to 1 kHz, and it has been demonstrated that a vibration attenuation of up to 16 dB can be achieved by using a magnetostrictive actuator in this model-based control scheme.