Distributed disturbance estimator and application to stabilization of multi-dimensional kirchhoff equation

In this paper, we present a linear disturbance estimator with time-varying gain to extract the real signal from the corrupted velocity signal. The approach comes from the active disturbance rejection control. A variant form of the estimator can also be served as a tracking differentiator. The estimator itself is relatively independent to the control plants. The result is applied to stabilization for a multi-dimensional Kirchhoff equation as a demonstration.