A CSEA Approach to Active Noise and Vibration Control

Active noise and vibration control (ANVC) has not lived up to its promise. Attempts in the 1930's had little success because of inability to control the phase in electronics and transducers. Digital processing appeared to offer a solution for dealingwith phase and arriving at algorithms of a complexity that could not be realized by analog systems. There are applications where ANVC has achieved success; exhaust and inlet silencers, noise canceling headsets and active engine mounts, for example. Butthe promises of ANVC and investments made to develop products have been disappointing. One reason is technical. ANVC has been successful when the transfer functions between disturbance and receiver are simple. The systems through which the signals travelin most situations are complicated, and in detail, unknowable. Individual systems are complicated, and multiple realizations are variable. The estimation methods that ANVC has employed have not been able to deal with them. But, techniques developed forstructural response estimation, machine diagnostics, and dereverberation offer new ways to achieve ANVC. We term this approach