Approximation-free Prescribed Performance Control with Prescribed Input Constraints

TL;DR

This paper introduces an approximation-free control method for unknown nonlinear systems that guarantees prescribed performance and input constraints without violations, under a specific feasibility condition.

Contribution

It proposes a novel, low-complexity, approximation-free controller that ensures constraint satisfaction in prescribed performance control for nonlinear systems.

Findings

Controller guarantees no constraint violations when feasibility condition holds.

Simulation results validate the effectiveness of the proposed method.

Addresses the trade-off between performance and input constraints.

Abstract

This paper considers the tracking control problem for an unknown nonlinear system with time-varying bounded disturbance subjected to a prescribed performance and input constraints. When performance and input constraints are specified simultaneously for such a problem, a trade-off is inevitable. Consequently, a feasibility condition for prescribing performance and input constraints is devised to address such difficulties of arbitrary prescription. In addition, an approximation-free controller with low complexity is proposed, which ensures that the constraints are never violated, provided that the feasibility condition holds. Finally, simulation results corroborate the effectiveness of the proposed controller.