Sampled-data robust control of a 2-DoF helicopter modeled using a quasi-LPV framework

The development of a sampled -data robust controller, applied to a 2-DoF helicopter system, is proposed in this paper. The helicopter presents a nonlinear dynamics, which is modeled in this paper using a quasiLPV approach, thus allowing the application of convex LMI conditions for the determination of the desired controllers. The robustness against effects such as sampling rate variation, noise and modeling approximations is assured mainly through a guaranteed bound for the 2 pound norm. Also, a performance index based on the 712 concept is used for the synthesis procedure, which is one of the main contributions of this paper. An algorithm is proposed to optimize the performance while guaranteeing the desired robustness. The analysis and validation of the proposed synthesis procedure are performed both through computational simulations and by applying the controllers on a physical 2-DoF helicopter, which could be satisfactorily stabilized.