On the order of nonlinear time-invariant stabilizing controllers

Abstract Here we consider the problem of stabilizing a finite-dimensional, stabilizable and detectable, linear time-invariant (LTI) plant in the sense that the plant state goes to zero while the controller state converges. With r the dimension of the plant output, we show that there exists a nonlinear time-invariant controller of order r +3 which stabilizes all such systems.