Composite adaptive posicast control for a class of LTI plants with known delay

Abstract

Many potential applications of adaptive control, such as adaptive flight control systems, require that the controller have high performance, stability guarantees, and robustness to time delays. These requirements typically lead to engineering trade-offs, such as a trade-off between performance and robustness. In this paper, a new Composite Adaptive Posicast Control (CAPC) framework is proposed for linear time-invariant (LTI) plants with input-matched parametric uncertainties and known delay. The CAPC architecture uses a combination of several modifications to the typical direct model reference adaptive control (MRAC). The described approach is a nonlinear controller design that explicitly accounts for known time delay. The stability of the overall closed-loop system can be guaranteed using nonlinear analysis tools. The benefits of the CAPC approach are explored using a simulation of the longitudinal dynamics of a fixed-wing aircraft. Comparison studies are presented for 80 ms and 250 ms time delay cases.