Fully Actuated Manifold Constraint Based Output Feedback Control for Input-Constrained Uncertain Nonlinear Systems
For control engineers dealing with uncertain nonlinear systems, this work provides a more general constraint control framework that handles input saturation without requiring system models.
This paper develops a low-complexity, model-free output-feedback controller for uncertain nonlinear systems with input constraints, achieving preset control accuracy under no saturation and flexible accuracy under saturation. The method extends constraint control from linear to nonlinear manifolds, with finite/fixed-time convergence demonstrated via simulations.
This paper presents a low-complexity, model-free, output-feedback controller for a class of unknown time-varying nonlinear systems with unknown input constraints. The controller achieves the preset control accuracy when the actuator is not saturated and maintains flexible control accuracy after actuator saturation. This result extends existing constraint control methods for linear manifolds to a more general form, including the construction of nonlinear manifolds and various types of constraints, thereby achieving preset control accuracy within finite or fixed time. Additionally, flexible control under unknown saturation is achieved through the construction of an error-driven flexible constraint. Finally, second-order and higher-order control examples and simulations are provided.