Adaptive Tracking Control of Constrained Nonlinear Systems and Its Application to Circuit Systems

An adaptive tracking control policy is investigated for uncertain nonlinear systems under the finite-time asymmetric output constraints (FTAOCs). Unlike common output constraints, FTAOCs are characterized as constraints that are initially imposed during system operation and are then removed after a certain time. To tackle this challenge, we have designed novel shift and barrier functions that transform FTAOCs into guarantees of boundedness for an auxiliary variable. Additionally, we have developed an adaptive estimation algorithm to estimate unknown parameters and proposed an adaptive control strategy. Simulation studies on the Resistance-inductance-capacitance (RLC) circuits have been conducted to demonstrate the feasibility of our proposal. In comparison with state-of-the-art methods, our algorithm offers the flexibility to simultaneously address both unconstrained and constrained requirements of nonlinear systems, without requiring revisions to the controller structure.