Further results on nonlinear receding horizon observers

In this paper, results are proposed that concern the design and the convergence of receding-horizon nonlinear observers. The key feature is the definition of the observability radius in relation to a pre-specified compact set of initial configurations. This enables a semi-global convergence result to be derived that turns out to be a global convergence result when appropriate regularity assumptions are made. A simple example is proposed to illustrate the basic features of the observers.