Research On Tracking Control Problems Of Two Types Of High-order Nonlinear Systems With State Constraints

State constraints always exist in real systems due to equipment limitations and performance requirements.Serious performance degradation and system instability may appear when constraints are violated.Hence,the research of constraints is of vital importance in nonlinear control fields.In this paper,the tracking control problems of two kinds of state-constrained high-order nonlinear systems are discussed.Main contents are:1.Event-triggered finite-time tracking of full-state constrained high-order nonlinear systemsThis part studies event-triggered practical finite-time tracking of full-state constrained high-order nonlinear systems.By introducing nonlinear state-dependent transformations into the adding a power integrator control design,asymmetric full-state constraints can be tackled without imposing feasibility conditions in traditional barrier Lyapunov functionbased methods.It is proved that the solution of the closed-loop system is semi-global practical finite-time stable,and the tracking error converges to an adjustable compact set around the origin in a finite-time.The designed event-triggered controller consumes less communication resources and ensures better control performance in constrained control framework.2.A nonlinear transformation-based approach to finite-time tracking of full-state constrained high-order nonlinear systemsThis part studies finite-time tracking of full-state constrained high-order nonlinear systems without feasibility conditions.By incorporating unified nonlinear state-dependent transformations into the adding a power integrator technique and combining the theory of fuzzy approximation,a state feedback controller is designed to prevent the violation of full-state constraints.It is proved that the solution of the closed-loop system is semi-global practical finite-time stable,and the tracking error converges to an adjustable compact set around the origin in a finite-time.Besides,the states of fuzzy systems stay within a specific compact set,on which fuzzy approximation is valid.