Output tracking in
nonminimum-phase nonlinear systems is a challenging, real-life control problem. In that class of dynamic systems, where the internal or zero-dynamics are unstable, traditional and powerful control methods such as feedback linearization  and sliding mode control [8, 9] can barely be used. Nonminimum-phase output tracking is extensively studied in linear  and nonlinear [11, 12] systems. A comprehensive review of different design methods for output tracking of nonlinear nonminimum phase systems is given in .