Output-feedback stabilization for planar output-constrained switched nonlinear systems

In this paper, globally asymptotical stabilization problem for a class of planar switched nonlinear systems with an output constraint via smooth output feedback is investigated. To prevent output constraint violation, a common tangent-type barrier Lyapunov function (tan-BLF) is developed. Adding a power integrator approach (APIA) is revamped to systematically design state-feedback stabilizing control laws incorporating the common tan-BLF. Then, based on the designed state-feedback controllers and a constructed common nonlinear observer, smooth output-feedback controllers, which can make the system output meet the predefined constraint during operation, are proposed to deal with the globally asymptotical stabilization problem of planar switched nonlinear systems under arbitrary switchings. A numerical example is employed to verify the proposed method.