Multi‐input–multi‐output system experimental validation of model‐free control and virtual reference feedback tuning techniques

This study proposes data‐driven model‐free adaptive control (MFAC), model‐free control (MFC) and virtual reference feedback tuning (VRFT) techniques applied to the control of a representative non‐linear multi‐input–multi‐output (MIMO) system represented by the twin rotor aerodynamic system (TRAS). These data‐driven techniques are implemented for both a single MIMO controller and two separately designed single‐input–single‐output controllers running in parallel for azimuth and pitch control. The three techniques are implemented as MFAC and MFC algorithms and as linear controllers tuned by VRFT. The performance of the three data‐driven MIMO control system structures is compared systematically on the basis of the experimental results in terms of the values of the sum of mean squared control errors measured on TRAS equipment.