String stability of a class of interconnected nonlinear system from the input to state view
This paper proposes a new definition of string stability from the input-to-state view. By viewing the interconnection as a kind of input to a subsystem, it specifies sufficient conditions of string stability for a class of directed circular interconnected nonlinear systems, which is based on the input-to-state stability analysis and singular perturbation theory. The proof is first conducted on a system with two subsystems, and then expanded to N subsystems. Furthermore, directed graph is used as an illustrative tool in this paper.