Design and analysis of hybrid control schemes for sandwich nonlinear systems

This paper addresses an open control problem: control of sandwich nonlinear systems. Of interest are sandwiched nonsmooth nonlinearities between linear dynamic blocks. Several hybrid control schemes for control of such sandwich systems are presented. The proposed control schemes employ an inner-loop discrete-time feedback design and an outer-loop continuous-time feedback design, combined with a nonlinearity inverse, to cancel the effect of the sandwiched nonlinearity, for improving output tracking. Stability and tracking performance of the closed-loop control system are analyzed.