ACTIVE VERSUS PASSIVE VIBRATION ABSORBERS

Passivity based control has several advantages, e.g., robustness and s implicity. However, the passivity constraint causes performance degrad ations. Specifically, the degree to which passively controlled absorbe r systems yield a flat response around the nominal absorber frequency is limited. An inherent flatness bound is derived using Nevanlinna-Pic k boundary interpolation theory. For active vibration absorbers, this limitation cancels, and magnitude response can be made arbitrarily fla t.