Invertibility of Nonlinear Interconnected System

This paper addresses the invertibility problem of interconnected system, which can be viewed as the distinguishability of the inputs at local level through their impacts on final products at the global level. The interconnected system involves two cascade nonlinear subsystems. In solving the invertibility problem, we give a necessary and sufficient condition for an interconnected system to be invertible, which says that the individual subsystems should be invertible. When individual subsystems are invertible, we present an algorithm for finding inputs of local subsystems that generate the given global outputs in a finite interval. Numerical examples are included to confirm the proposed algorithm.