Indirect Binary Model Reference Adaptive Control

This paper proposes an Indirect Binary Model Reference Adaptive Controller (IB-MRAC), with the main objective of combining the steady-state features of controllers based in integral parameter adaptation with the fast and non oscillatory transient of variable structure based strategies. The indirect approach offers the possibility to get an easier controller design, either in the selection of the initial estimatives for the plant parameters or in the definition of a suitable region (ball) in which these ones should not escape. These more intuitive selections are due to the direct relationship between the plant parameters and physical system parameters, as inertia moments, resistances, capacitances, etc. The choice of adaptive gains defines how the IB-MRAC behaves between the Indirect MRAC (IMRAC) and the recently proposed Indirect Variable Structure Model Reference Adaptive Control (IVS-MRAC). Simulations to an unstable second order plant and a stability analysis for plants of relative degree one are presented, ensuring the global stability of system, considering a persistently exciting reference signal.