This article provides a comprehensive study about optimization and real-time implementation of H∞ model-based controller for uncertain systems (having external perturbations) using robust control methods. The complicated air vehicle modeling is quite difficult because of highly nonlinear behavior, un-modeled states, and cross-coupling effect. The helicopter flight control also depends on two rotors generating continuous thrust simultaneously in two different directions. Simple linear feedback controllers cannot ensure the stability of highly nonlinear systems like a helicopter. The controllability and observability full rank matrix output ensure the credibility of the system before a controller design. The design of a robust controller for the desired flight control, demands the availability of all its states and varying parameters for real-time robust feedback control. However, its prototype, Twin-rotor MIMO System (TRMS) facilitates the researchers and control engineers in terms of the real-time environment of a helicopter flight control. Various control strategies are presented to elaborate the behavior of the MIMO system and the limitations of robust control methods. Each control strategy has been comprehensively discussed with the stability analysis and the design requirements. The considered control techniques, such as the loop-shaping control and H∞ model-based control augmented with mixed sensitivity control function, make use of control in such a way that robust stability and robust performance are ensured for highly nonlinear systems. Model-based H∞ optimization technique elaborates the robustness and stability of the system by reducing tracking error of all its states towards origin and thereafter system becomes stable for an infinite period. The loop-shaping control performance as compared to H∞ model-based control has some limitations to ensure closed-loop robustness and real-time implementation under perturbations. The performance evaluation is done at the end which shows that the H∞ model-based control gives optimal robust performance including perturbations and coupling effect. The real-time implementation on MATLAB/Simulation via personal computer validates the worth of the optimization method in the presence of uncertainties (matched, unmatched, coupling effect) of a linearized state-space model of the TRMS system.

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