Adaptive robust regulation of linear multivariable systems: Tracking signals generated by models with unknown parameters

The regulator problem is considered in the context of linear time-invariant multivariable systems. The exogeneous signal, the disturbance and/or reference signal, is assumed to be generated by a model (the exomodel) with unknown initial conditions. Unlike in previous treatments, the exomodel parameters are not assumed known. A two-stage adaptive control scheme is presented, the first stage being an identifier of the exomodel and the second stage a time-varying robust regulator containing an internal model of the exomodel which is tuned on-line by the first stage.